The two main types of germ cell tumors are seminomas (40 percent) and non-seminomatous germ cell tumors (60 percent).
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Germ cell tumors account for less than 2% of ovarian cancers overall.
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Over 90 percent of testicular cancers are what are known as germ cell tumors.
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Most advances in treatment have been limited to germ cell tumors, which account for less than 10 percent of ovarian cancers.
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The exception is if the altered DNA is put into a germ cell: the cells that turn into sperm and eggs.
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Which of these a primordial germ cell goes on to become depends on the sex of the tissue it finds itself in.
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When Emily Caudill learned she had an ovarian germ cell tumor at the age of 25, she did not want to undergo chemotherapy.
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Through the process of meiosis, a germ cell with two sets of chromosomes splits into sex cells, each with only one set of chromosomes.
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Or Type 223 diabetes, asthma, allergies, dental cavities, or the following types of cancer: acute non-lymphoblastic leukemia, non-Hodgkin lymphoma, central nervous system cancers, malignant germ cell tumors, juvenile bone tumors, and other solid cancers.
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He told her not to worry, but after months of testing and a procedure to remove it, that cyst turned out to be a malignant germ-cell tumor, which is a rare form of ovarian cancer.
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Gantz and his thesis adviser, Ethan Bier, a professor of cell and developmental biology at U.C. San Diego, decided to try putting the Crispr editing machinery into a germ cell, along with the gene it was originally tied to.
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Scientists have already used cloning to restore, for a few brief minutes, the Pyrenean ibex, a method that relies on using the nucleus of the somatic cell of an extinct species and transferring it into the germ cell of a host species.
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The mnemonic for what this anterior mediastinal tumor could represent was "The Four T's": abnormalities of the Thymus, Thyroid, a Teratoma (a type of germ cell tumor containing several different types of tissue, even sometimes hair and muscle), or a Terrible lymphoma.
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But by the second week of July, I was sitting in an oncologist's office at Memorial Sloan Kettering Cancer Center, waiting to hear my treatment plan for what turned out to be an ovarian germ cell tumor, a very rare type of ovarian cancer that originates in the egg cell.
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Right before I started treatment, I was asked to participate in a study called Make-an-Impact, which is a research project at Memorial Sloan Kettering that collects genomic data from patients so doctors and scientists can learn more about germ cell tumors, and other specific types of rare cancers.
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Malignant germ cell tumors of the mediastinum are uncommon, representing only 3 to 10% of tumors originating in the mediastinum. They are much less common than germ cell tumors arising in the testes, and account for only 1 to 5% of all germ cell neoplasms. Syndromes associated with mediastinal germ cell tumors include Hematologic Neoplasia and Klinefelter's syndrome.
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Spermatocytic tumors are not considered a subtype of seminoma and unlike other germ cell tumours do not arise from intratubular germ cell neoplasia.
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Primordial Germ Cell Migration Primordial germ cell (PGC) migration is the process of distribution of primordial germ cells throughout the embryo during embryogenesis.
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Mediastinal germ cell tumors are tumors that derive from germ cell rest remnants in the mediastinum. They most commonly occur in the gonad but occasionally elsewhere.
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Testicular germ cell cancer (TGCC) shows a strong genetic disposition, with the most significant gene variants being those linked to gonad formation and germ cell function.
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Spermatocytic tumor is not considered a subtype of seminoma and, unlike seminoma and most other germ cell tumours, it does not arise from intratubular germ cell neoplasia. It has not been described as arising in locations outside the testis, and does not occur in association with other germ cell tumours.Mills, S (ed.) 2009.Sternberg's Diagnostic Pathology.
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It is also used for palliation of chemotherapy-resistant germ cell tumors.
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Germ cell tumors of the ovary develop from the ovarian germ cells. Germ cell tumor accounts for about 30% of ovarian tumors, but only 5% of ovarian cancers, because most germ-cell tumors are teratomas and most teratomas are benign. Malignant teratomas tend to occur in older women, when one of the germ layers in the tumor develops into a squamous cell carcinoma. Germ-cell tumors tend to occur in young women (20s–30s) and girls, making up 70% of the ovarian cancer seen in that age group.
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Malignant mediastinal germ cell tumors of various histologies were first described as a clinical entity approximately 50 years ago. Mediastinal and other extragonadal germ cell tumors were initially thought to represent isolated metastases from an inapparent gonadal primary site.
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Mutations in this gene have been linked to severe spermatogenic failure and infertility in males. In mice and pigs deficient in DAZL, PGCs migrate to the gonad but do not undertake germ cell determination, and may instead produce germ cell tumors.
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However, a large meta-analysis has shown that in individuals with associated risk factors for testicular germ cell tumor, the increase in risk of concurrent diagnosis of testicular germ cell tumor, or testicular carcinoma- in-situ upon biopsy is approximately eight to ten-fold. There is extensive controversy over whether testicular microlithiasis in individuals with testicular germ cell tumor, or risk factors for such, should undergo testicular biopsy to exclude the presence of testicular carcinoma-in-situ, also known as intratubular germ cell neoplasia of unclassified type. Additionally, whether the presence of testicular microlithiasis should influence decision for adjuvant chemotherapy or surveillance in individuals with testicular germ cell tumor remains unclear. A recent review in Nature Reviews Urology has comprehensively evaluated these topics.
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In 25% of germ-cell tumors, the cancer is discovered during a routine examination and does not cause symptoms. Diagnosing germ cell tumors may be difficult because the normal menstrual cycle and puberty can cause pain and pelvic symptoms, and a young woman may even believe these symptoms to be those of pregnancy, and not seek treatment due to the stigma of teen pregnancy. Blood tests for alpha-fetoprotein, karyotype, human chorionic gonadotropin, and liver function are used to diagnose germ cell tumor and potential co- occurring gonadal dysgenesis. A germ cell tumor may be initially mistaken for a benign ovarian cyst.
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Germinomas are thought to originate from an error of development, when certain primordial germ cells fail to migrate properly. Germinomas lack histologic differentiation, whereas nongerminomatous germ-cell tumors display a variety of differentiation. Like other germ-cell tumors, germinomas can undergo malignant transformation.
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During this, the trophocyte divides via binary fission into a secondary trophocyte and a germ cell. The germ cell will then divide into many sporocytes. The secondary trophocyte may divide into a tertiary trophocyte and another germ cell, which may then produce a second layer of sporocytes. These repeated binary fissions continue in the absence of an intermediate growth stage, to get multiple layers of the multicellular growth that is the trophont.
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Germ-cell tumors can include dysgerminomas, teratomas, yolk sac tumors/endodermal sinus tumors, and choriocarcinomas, when they arise in the ovary. Some germ-cell tumors have an isochromosome 12, where one arm of chromosome 12 is deleted and replaced with a duplicate of the other. Most germ-cell cancers have a better prognosis than other subtypes and are more sensitive to chemotherapy. They are more likely to be stage I at diagnosis.
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An immature teratoma is a teratoma that contains anaplastic immature elements, and is often synonymous with malignant teratoma. A teratoma is a tumor of germ cell origin, containing tissues from more than one germ cell line, It can be ovarian or testicular in its origin. and are almost always benign. An immature teratoma is thus a very rare tumor, representing 1% of all teratomas, 1% of all ovarian cancers, and 35.6% of malignant ovarian germ cell tumors.
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Germ cell neoplasia in situ (GCNIS) represents the precursor lesion for many types of testicular germ cell tumors. As the name suggests, it represents a neoplastic process of germ cells that is confined to the spermatogonial niche. The term GCNIS was introduced with the 2016 edition of the WHO classification of urological tumours. GCNIS more accurate describes the lesion as it arises between the basement membrane and Sertoli cells (the cells that 'nurse' the developing germ cell).
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Additionally, zero population growth (zpg), encoding a germline-specific gap junction is required for germ cell differentiation.
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Germ cell tumor is a rare cancer that can affect people at all ages. As of 2018, germ cell tumors account for 3% of all cancers in children and adolescents 0-19 years old. Germ cell tumors are generally located in the gonads but can also appear in the abdomen, pelvis, mediastinum, or brain. Germ cells migrating to the gonads may not reach that intended destination and a tumor can grow wherever they end up, but the exact cause is still unknown.
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Germ cell-less, spermatogenesis associated 1 is a protein that in humans is encoded by the GMCL1 gene.
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Embryonal carcinoma is a relatively uncommon type of germ cell tumour that occurs in the ovaries and testes.
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In 2009, Daling published a study which found an association between marijuana use and incidence of testicular germ cell tumors.
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An oocyte (, ), oöcyte, ovocyte, or rarely ocyte, is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in the ovary during female gametogenesis. The female germ cells produce a primordial germ cell (PGC), which then undergoes mitosis, forming oogonia.
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Malignant germ cell tumors are the type of ovarian cancer most likely to occur during pregnancy. They are typically diagnosed when an adnexal mass is found on examination (in 1–2% of all pregnancies), a tumor is seen on ultrasound, or the parent's level of alpha-fetoprotein is elevated. Dermoid cysts and dysgerminomas are the most common germ cell tumors during pregnancy. Germ cell tumors diagnosed during pregnancy are unlikely to have metastasized and can be treated by surgery and, in some cases, chemotherapy, which carries the risk of birth defects.
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The germ cell nuclear factor (GCNF), also known as RTR (retinoid receptor- related testis-associated receptor) or NR6A1 (nuclear receptor subfamily 6, group A, member 1), is a protein that in humans is encoded by the NR6A1 gene. GCNF is a member of the nuclear receptor family of intracellular transcription factors . In adults, GCNH is expressed mainly in the germ cells of gonads and is involved in the regulation of embryogenesis and germ cell differentiation. Its expression pattern suggests that it may be involved in neurogenesis and germ cell development.
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GCNIS is generally treated by radiation therapy and/or orchiectomy. Chemotherapy used for metastatic germ cell tumours may also eradicate GCNIS.
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This can conclude that it is a potential source for regulating the level of BMP signaling and can affect germ cell specification.
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Germ cell tumors of the testis are the most common cancer in young men between the ages of 15 and 35 years.
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Growing teratoma syndrome is a rare complication of teratoma that can occur when an immature ovarian germ cell teratoma is treated by chotherapy.
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American Society of Parasitologist. 1979 (65)1:35-37. Woude, Anne. Germ Cell Cycle of Megalodiscus temperatus (Stafford, 1905) Harwood, 1932 (Paramphistomidae: Trematoda).
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Testicular germ cell tumors, that occur primarily in young adults, are the consequent of preinvasive cells called carcinoma in situ (CIS). The development of CIS is due to fetal germ cells, such as gonocytes, arrested in quiescence and unable to properly differentiate. This leads to malignant transformation of the germ cells until it becomes an overt germ cell cancer after puberty.
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These include germ cell tumors, granulomas of Langerhans cell histiocytosis and hypothalamic astrocytomas, as these lesions usually demonstrate at least partial uptake of contrast.
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Neoplasms of possible hemic and germ cell origin were also found in clams from the station with potentially higher organic and heavy metal contamination.
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LRRIQ1 is lowly expressed (0.6 times the average gene) in lung, testis, epithelial tissue, pooled germ cell tumors, brain tissues, embryonic tissues, and adipose tissues.
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There are two types of classification for the extracranial germ cell tumor. One is GCT biology and another is to classify EGCT into 3 types. Both classifications are used by professionals to diagnose the type of tumor the patient has by the assistance of multiple results from different testaments. The first classification organized the EGCTs into two types, gonadal and extragonadal germ-cell tumor.
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Among other mechanisms, her laboratory discovered that a polyadenylated tail is not required for gene regulation. Lehmann continued to focus her research efforts on germ cell differentiation well into the early 2000s. She played a substantial role in the discovery of germ cell migratory pathways (namely those involving gap junctions, G protein-coupled receptors like Tre-1, and isoprenoids), particularly those concerning migration into the ovaries and testis. In 2005, Lehmann’s laboratory published a paper relating the lipid phosphatases Wunen and Wunen 2 to germ cell migration and elimination, suggesting that germ cells are sorted into the gonads by a type of repellent mechanism.
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A germinoma is a type of germ-cell tumor, which is not differentiated upon examination.Germinoma, Central Nervous System at eMedicine It may be benign or malignant.
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The genetic lineage-tracing experiments indicate that the Blimp1-positive cells originating from the proximal posterior epiblast cells are indeed the lineage-restricted primordial germ cell precursors.
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A seminoma is a germ cell tumor of the testicle or, more rarely, the mediastinum or other extra-gonadal locations. It is a malignant neoplasm and is one of the most treatable and curable cancers, with a survival rate above 95% if discovered in early stages. Testicular seminoma originates in the germinal epithelium of the seminiferous tubules. About half of germ cell tumors of the testicles are seminomas.
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When the cancer cells are poorly differentiated (that is, they look less evolved than normal cells when viewed under a microscope), the cancer may be either a lymphoma or a germ cell tumor. Lymphomas begin in the lymphatic system. Germ cell tumors usually begin in the ovaries and testes. In patients in whom the primary cancer is eventually found, the lung and pancreas are the most common primary cancer sites.
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These genes play a role in germ line development to localize nanos mRNA to the posterior and localize germ cell determinants. Drosophila progeny with mutations in these genes fail to produce pole cells and are thus sterile, giving these mutations the name 'grandchildless'. The genes Oskar, nanos and germ cell-less (gcl) have important roles. Oskar is sufficient to recruit the other genes to form functional germ plasm.
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Adult-AMKL may occur in individuals who have a prior diagnosis of and/or present with chronic myelogenous leukemia, polycythemia vera, essential thrombocytosis, primary myelofibrosis, or mediastinal germ cell tumor. AMKL associated with mediastinal germ cell tumors typically occurs in younger adults, i.e. ages 13–36 (average age 24). Cases occurring in children aged ≤18 years, which represent ~20% of all cases, could be regarded in the non-DS-AMKL category.
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Success of germ cell proliferation and differentiation is also ensured by a balance between germ cell development and programmed cell death. Identification of «death triggering signals» and corresponding receptor proteins is important for the fertilization potential of males. Apoptosis in germ cells can be induced by variety of naturally occurring toxicant. Receptors belonging to the taste 2 family are specialized to detect bitter compounds including extremely toxic alkaloids.
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Murbræch became a physician and took the PhD degree in 2017 with the thesis Cardiovascular status in long term survivors of lymphomas and malignant ovarian germ cell tumors.
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The type I and II interferon induce IFITM proteins expression significantly. IFITM proteins are involved in the physiological process of immune response signaling, germ cell maturation and development.
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The risk of malignant germ cell tumors in women with CAIS increases with age and has been estimated to be 3.6% at 25 years and 33% at 50 years. The incidence of gonadal tumors in childhood is thought to be relatively low; a recent review of the medical literature found that only three cases of malignant germ cell tumors in prepubescent girls have been reported in association with CAIS in the last 100 years. Some have estimated the incidence of germ cell malignancy to be as low as 0.8% before puberty. Vaginal hypoplasia, a relatively frequent finding in CAIS and some forms of PAIS, is associated with sexual difficulties including vaginal penetration difficulties and dyspareunia.
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Lehmann published her first paper in 1981 under her Fulbright Fellowship mentor Campos-Ortega, detailing her study of early neurogenesis in Drosphila and the effects of lethal mutations on neural and epidermal cell precursors. Under Nüsslein-Volhard, Lehmann began to study maternal genes like oskar, pumilio, and nanos, comparing the effects of maternal versus zygotic genes in germ cell formation, abdominal patterning, and cell signaling. Using molecular cloning techniques, she discovered that oskar and nanos RNA transcripts regulate gene expression and germ cell formation by localizing at the posterior embryonic pole. Her later work continues to build on this discovery by analyzing modification mechanisms of RNA transcript production and how they affect germ cell differentiation and localization in Drosophila.
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The finding of elevated amounts of alpha-fetoprotein is more suggestive of a mixed germ cell tumour, with the alpha-fetoprotein being released by the yolk sac tumour component.
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If a mutation is present in a germ cell, it can give rise to offspring that carries the mutation in all of its cells. This is the case in hereditary diseases. In particular, if there is a mutation in a DNA repair gene within a germ cell, humans carrying such germline mutations may have an increased risk of cancer. A list of 34 such germline mutations is given in the article DNA repair-deficiency disorder.
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PIWI proteins play a crucial role in fertility and germline development across animals and ciliates. Recently identified as a polar granule component, PIWI proteins appear to control germ cell formation so much so that in the absence of PIWI proteins there is a significant decrease in germ cell formation. Similar observations were made with the mouse homologs of PIWI, MILI, MIWI and MIWI2. These homologs are known to be present in spermatogenesis.
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A combination of carboplatin and paclitaxel is often used. Advances techniques such as FISH and tissue of origin testing may also be employed. Germ cell tumors often carry abnormality of chromosome 12, which if identified, directs treatment for metastatic germ cell tumors. No method is standard for all forms of CUP, but chemotherapy, radiation therapy, hormone therapy, and surgery may be used alone or in combination to treat patients who have CUP.
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Fewer than 6 weeks (cycles) of treatment is less effective than 6 weeks or more. Germ-cell malignancies are treated differently than other ovarian cancers — a regimen of bleomycin, etoposide, and cisplatin (BEP) is used with 5 days of chemotherapy administered every 3 weeks for 3 to 4 cycles. Chemotherapy for germ cell tumors has not been shown to cause amenorrhea, infertility, birth defects, or miscarriage. Maintenance chemotherapy has not been shown to be effective.
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The development of germ cells can be divided into two phases. The first phases involves the fetal and neonatal phases of germ cell development that lead to the formation of the SSCs. The second phase is spermatogenesis, which is a cycle of regulated mitosis, meiosis and differentiation (via spermiogenesis) leading to the production of mature spermatozoa, also known as sperm cells. Gonocytes are functionally present during the first phase of germ cell maturation and development.
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In the testis pure embryonal carcinoma is also uncommon, and accounts for approximately ten percent of testicular germ cell tumours. However, it is present as a component of almost ninety percent of mixed nonseminomatous germ cell tumours. The average age at diagnosis is 31 years, and typically presents as a testicular lump which may be painful. One fifth to two thirds of patients with tumours composed predominantly of embryonal carcinoma have metastases at diagnosis.
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Endodermal sinus tumor (EST) is a member of the germ cell tumor group of cancers. It is the most common testicular tumor in children under 3, and is also known as infantile embryonal carcinoma. This age group has a very good prognosis. In contrast to the pure form typical of infants, adult endodermal sinus tumors are often found in combination with other kinds of germ cell tumor, particularly teratoma and embryonal carcinoma.
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Grafting, 1870, by Winslow Homer an example of grafting. Fruit tree propagation is usually carried out vegetatively (non-sexually) by grafting or budding a desired variety onto a suitable rootstock. Perennial plants can be propagated either by sexual or vegetative means. Sexual reproduction begins when a male germ cell (pollen) from one flower fertilises a female germ cell (ovule, incipient seed) of the same species, initiating the development of a fruit containing seeds.
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Protein Wnt-8a is a protein that in humans is encoded by the WNT8A gene. Wnt8a may be involved in development of early embryos as well as germ cell tumors.
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The increased expression of the Blimp-1 protein in B lymphocytes, T lymphocytes, NK cell and other immune system cells leads to an immune response through proliferation and differentiation of antibody secreting plasma cells. Blimp-1 is also considered a 'master regulator' of hematopoietic stem cells. Blimp1 (also known as Prdm1), a known transcriptional repressor, has a critical role in the foundation of the mouse germ cell lineage, as its disruption causes a block early in the process of primordial germ cell formation. Blimp1-deficient mutant embryos form a tight cluster of about 20 primordial germ cell-like cells, which fail to show the characteristic migration, proliferation and consistent repression of homeobox genes that normally accompany specification of primordial germ cells.
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Ovarian germ cell tumors (OGCTs) are heterogeneous tumors that are derived from the primitive germ cells of the embryonic gonad, which accounts for about 2.6% of all ovarian malignancies. There are four main types of OGCTs, namely dysgerminomas, yolk sac tumor, teratoma, and choriocarcinoma. Dygerminomas are Malignant germ cell tumor of ovary and particularly prominent in patients diagnosed with gonadal dysgenesis. OGCTs are relatively difficult to detect and diagnose at an early stage because of the nonspecific histological characteristics.
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They frequently metastasize to nearby lymph nodes, especially para-aortic and pelvic lymph nodes. The most common symptom of germ cell tumors is subacute abdominal pain caused by the tumor bleeding, necrotizing, or stretching the ovarian capsule. If the tumor ruptures, causes significant bleeding, or torses the ovary, it can cause acute abdominal pain, which occurs in less than 10% of those with germ-cell tumors. They can also secrete hormones which change the menstrual cycle.
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Johnsen proposed a more quantitative analysis of testis cellular architecture based on the concept that testis damage causes a successive disappearance of the most mature germ cell type.Johnsen SG. Testicular biopsy score count--a method for registration of spermatogenesis in human testes: normal values and results in 335 hypogonadal males. Hormones 1970;1:2-25. The Johnsen scoring system involves a quantitative assessment of individual germ cell types that is very detailed and relatively laborious for routine clinical use.
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HMG-CoA reductase is an important developmental enzyme. Inhibition of its activity and the concomitant lack of isoprenoids that yields can lead to germ cell migration defects as well as intracerebral hemorrhage.
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Anatomical Record 34: 337-358. which has been suggested to reduce the spontaneous rate of germ cell mutations.Ehrenberg L., von Ehrenstein G., Hedgram A. (1957). Gonad temperature and spontaneous mutation-rate in man.
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Extavour received an Honors BSc at the University of Toronto. Her Ph.D. thesis was on germ cell selection in genetic mosaics and was published in 2001 in PNAS. In 2003 Extavour did a study at Cambridge University on the mechanisms of germ cell formation that showed animal germ cells were likely specified by inductive signals more often than previously thought. This went against the mainstream scientific view at the time that animal germ cells are usually specified by maternally inherited determinants.
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Recurrences can be treated, but the disease-free interval tends to shorten and chemoresistance increases with each recurrence. When a dysgerminoma recurs, it is most likely to recur within a year of diagnosis, and other malignant germ cell tumors recur within 2 years 90% of the time. Germ cell tumors other than dysgerminomas have a poor prognosis when they relapse, with a 10% long-term survival rate. Low malignant potential tumors rarely relapse, even when fertility-sparing surgery is the treatment of choice.
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Mixed tumors contain elements of more than one of the above classes of tumor histology. To be classed as a mixed tumor, the minor type must make up more than 10% of the tumor. Though mixed carcinomas can have any combination of cell types, mixed ovarian cancers are typically serous/endometrioid or clear cell/endometrioid. Mixed germ cell tumors make up approximately 25–30% of all germ cell ovarian cancers, with combinations of dysgerminoma, yolk sac tumor, and/or immature teratoma.
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Human chorionic gonadotropin can be used as a tumor marker, as its β subunit is secreted by some cancers including seminoma, choriocarcinoma, germ cell tumors, hydatidiform mole, teratoma with elements of choriocarcinoma, and islet cell tumor. For this reason, a positive result in males can be a test for testicular cancer. The normal range for men is between 0-5 mIU/mL. Combined with alpha-fetoprotein, β-HCG is an excellent tumor marker for the monitoring of germ cell tumors.
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DAZ is not absolutely required for spermatogenesis as some DAZ deleted men are still able to father children. DAZ pushes ESCs in to germ cells with molecular features of being spermatids. DAZL is expressed in humans from early progenitor germ cell migration, right up to spermatozoa differentiation. Since DAZL is located on an autosome, it has been shown to be important in germ cell development of both oocyte and spermatocytes (in spermatogenesis and oogenesis), albeit in different expression patterns for both.
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In people with BRCA mutations, platinum chemotherapy is more effective. Germ-cell tumors and malignant sex-cord/stromal tumors are treated with chemotherapy, though dysgerminomas and sex-cord tumors are not typically very responsive.
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These tumors can be benign or malignant. On arrival at the gonad, primordial germ cells that do not properly differentiate may produce germ cell tumors of the ovary or testis in a mouse model.
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Blood or urine tests measure hCG. These can be pregnancy tests. hCG-positive indicates an implanted blastocyst and mammalian embryogenesis. These can be done to diagnose and monitor germ cell tumors and gestational trophoblastic diseases.
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While it is often recommended that women with CAIS eventually undergo gonadectomy to mitigate cancer risk, there are differing opinions regarding the necessity and timing of gonadectomy. The risk of malignant germ cell tumors in women with CAIS increases with age and has been estimated to be 3.6% at 25 years and 33% at 50 years. However, only three cases of malignant germ cell tumors in prepubescent girls with CAIS have been reported in the last 100 years. The youngest of these girls was 14 years old.
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These researchers produced primordial germ cell-like cells (PGLCs) from embryonic stem cells (ESCs) and skin cells in vitro. Hayashi and Saitou's group was able to promote the differentiation of embryonic stem cells into PGCs with the use of precise timing and bone morphogenetic protein 4 (Bmp4). Upon succeeding with embryonic stem cells, the group was able to successfully promote the differentiation of induced pluripotent stem cells (iPSCs) into PGLCs. These primordial germ cell-like cells were then used to create spermatozoa and oocytes.
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Rare cases of adult onset acute megakaryoblastic leukemia are associated with malignant mediastinal germ cell tumor. In these cases, the mediastinal germ cell tumor develops before or concomitantly with but not after acute megakaryoblastic leukemia. The three most common genetic aberrations in the bone marrow cells of these individuals (representing ~65% of all cases) are inversions in the long arm of chromosome 12, trisomy 8, and an extra X chromosome. In several of these cases, the genetic aberrations in the malignant megakaryoblasts were similar to those in the malignant mediastinal germ cells.
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There are two mechanisms to establish the germ cell lineage in the embryo. The first way is called preformistic and involves that the cells destined to become germ cells inherit the specific germ cell determinants present in the germ plasm (specific area of the cytoplasm) of the egg (ovum). The unfertilized egg of most animals is asymmetrical: different regions of the cytoplasm contain different amounts of mRNA and proteins. The second way is found in mammals, where germ cells are not specified by such determinants but by signals controlled by zygotic genes.
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The treatment for mediastinal nonseminomatous germ cell tumors should follow guidelines for poor-prognosis testicular cancer. Initial treatment with four courses of bleomycin, etoposide, and cisplatin, followed by surgical resection of any residual disease, is considered standard therapy.
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TTC39B is well expressed in muscles, internal organs, secretory organs, reproductive organs, the immune system, and the nervous system. TTC39B is expressed in a multitude of tissues: testis, lung, islets of langerhans, pancreas, kidney, pooled germ cell tumors, breast carcinoma, etc.
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Although almost exclusively associated with pregnancy, EPF-like activity has also been detected in tumors of germ cell origin and in other types of tumors. Its utility as a tumour marker, to evaluate the success of surgical treatment, has been suggested.
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Prior to their occupation of the genital ridge, there is no known difference between XX and XY PGCs. However, once migration is complete and germ cell determination has occurred, these germline cells begin to differentiate according to the gonadal niche.
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Sertoli cell-only syndrome (a.k.a. Del Castillo syndrome and germ cell aplasia ) is a disorder characterized by male sterility without sexual abnormality. It describes a condition of the testes in which only Sertoli cells line is present in seminiferous tubules..
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Main article: Primordial germ cell migration Primordial germ cells, germ cells that still have to reach the gonads (also known as PGCs, precursor germ cells or gonocytes) divide repeatedly on their migratory route through the gut and into the developing gonads.
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Relative incidence of cutaneous cysts. Pilonidal cyst is labeled near top. A pilonidal cyst can resemble a dermoid cyst, a kind of teratoma (germ cell tumor). In particular, a pilonidal cyst in the gluteal cleft can resemble a sacrococcygeal teratoma.
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Yolk sac tumors, formerly called endodermal sinus tumors, make up approximately 10–20% of ovarian germ cell malignancies, and have the worst prognosis of all ovarian germ cell tumors. They occur both before menarche (in one-third of cases) and after menarche (the remaining two- thirds of cases). Half of the people with yolk sac tumors are diagnosed in stage I. Typically, they are unilateral until metastasis, which occurs within the peritoneal cavity and via the bloodstream to the lungs. Yolk sac tumors grow quickly and recur easily, and are not easily treatable once they have recurred.
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Pluripotent stem cells are used in lieu of in vivo cells when researching germ cell development but is not without its issues. There is a limited amount of information on early germ cells, so it is difficult to ascertain if the resultant cells in the culture are the same as germ cells. Instead, research is based on inducing cells with the same or similar properties in order to study the underlying mechanisms of germ cell differentiation. Additionally, it is also difficult to compare with previous studies, especially since the majority have been done on mice, and there are different processes between species.
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FANCD2 mutant mice exhibit chromosome mis-pairing during the pachytene stage of meiosis and germ cell loss. Activated FANCD2 protein may normally function prior to the initiation of meiotic recombination, perhaps to prepare chromosomes for synapsis, or to regulate subsequent recombination events.
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Increased H19 expression is found in the following cancers: adrenocortical neoplasms, choriocarcinomas, hepatocellular carcinomas, bladder cancers, ovarian serous epithelial cancers, head and neck carcinomas, endometrial cancer, breast cancer, acute T cell leukemia/lymphoma, Wilms' tumor, testicular germ cell cancer, esophageal cancer and lung cancer.
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The barrier also protects the germ cells from blood-borne noxious agents, prevents antigenic products of germ cell maturation from entering the circulation and generating an autoimmune response, and may help establish an osmotic gradient that facilitates movement of fluid into the tubular lumen.
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CD30 is associated with anaplastic large cell lymphoma. It is expressed in embryonal carcinoma but not in seminoma and is thus a useful marker in distinguishing between these germ cell tumors. CD30 and CD15 are also expressed on Reed-Sternberg cells typical for Hodgkin's lymphoma.
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In the context of evidence-based medicine, AFP is validated at the highest level as a tumor marker for use in patients with nonseminomatous germ cell tumors. There are case reports of elevated AFP associated with teratoma. However, some of these case reports involve infants but do not correct for the normal elevation of AFP in infants, while others ignore the likelihood that teratoma (and other germ cell tumors) may in fact be mixed tumors containing elements of endodermal sinus tumor. AFP is normally elevated in infants, and because teratoma is the single most common kind of tumor in infants, several studies have provided reference ranges for AFP in normal infants.
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As of 2010, over 400 AR mutations have been reported in the AR mutation database, and the number continues to grow. Inheritance is typically maternal and follows an X-linked recessive pattern; individuals with a 46,XY karyotype always express the mutant gene since they have only one X chromosome, whereas 46,XX carriers are minimally affected. About 30% of the time, the AR mutation is a spontaneous result, and is not inherited. Such de novo mutations are the result of a germ cell mutation or germ cell mosaicism in the gonads of one of the parents, or a mutation in the fertilized egg itself.
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The germ cell population (~40 in mice), after specification, migrate to the developing gonads where they differentiate further into gametogonia. Much of the research in germ cell development is done on animal models. Animal models are an effective research tool due to the commonality of sexual reproduction which is thought to have same or similar mechanisms across species. The majority of research is done on mice which has led to advances in understanding germ line differentiation across all mammal but there are some species specific mechanisms which have not been studied as extensively due to the difficulty of both obtaining human samples and the ethical limitations of human research.
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In the ovary, embryonal carcinoma is quite rare, amounting to approximately three percent of ovarian germ cell tumours. The median age at diagnosis is 15 years. Symptoms and signs are varied, and may include sexual precocity and abnormal (increased, reduced or absent) uterine bleeding.Mills, S (ed.) 2009.
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On June 21, 2009, a skatepark was added to Urbana's Melvin Miller Park. In November 2013, Damian Prendergast, who was a local skateboarder, died from germ cell cancer. Following his death, his high school class raised $700 and support to dedicate the skatepark in Damian's name.
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Spermatocytic tumor, previously called spermatocytic seminoma, is a neoplasm of the testis (i.e. a tumour of the testis), and classified as a germ cell tumour. The name of the tumour comes from the similarity (under the microscope) between the small cells of the tumour and secondary spermatocytes.
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Scheme showing analogies in the process of maturation of the ovum and the development of the spermatids.A gametocyte is a eukaryotic germ cell that divides by mitosis into other gametocytes or by meiosis into gametids during gametogenesis. Male gametocytes are called spermatocytes, and female gametocytes are called oocytes.
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The diagnosis of a mediastinal germ cell tumor should be considered in all young males with a mediastinal mass. In addition to physical examination and routine laboratory studies, initial evaluation should include CT of the chest and abdomen, and determination of serum levels of HCG and alpha-fetoprotein.
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FANCB mutant mice are infertile and exhibit primordial germ cell defects during embryogenesis. The germ cells and testicular size are severely compromised in FANCB mutant mice. FANCB protein is essential for spermatogenesis and likely has a role in the activation of the Fanconi anemia DNA repair pathway during meiosis.
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The number of new cases a year in the US is 0.4 per 100,000 women and 0.2 per 100,000 women, respectively. In young people, sex-cord stromal tumors and germ cell tumors total 1% of overall ovarian cancer. Ovarian cancer represents approximately 4% of cancers diagnosed in women.
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" Because each germ cell normally has 46 chromosomes, the process of "fertilization" can not take place until the total number of chromosomes in each germ cell are cut in half. This is necessary so that after their fusion at fertilization the characteristic number of chromosomes in a single individual member of the human species (46) can be maintained, otherwise we would end up with a monster of some sort." Others have disputed this view. Law professor and ethicist Richard Stith has written that the proper word for the growth of a fetus is not construction, as of a house or car, but development, as of a (pre-digital-era) photograph or a tree sapling: > Human beings do develop.
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The spermatozoa of animals are produced through spermatogenesis inside the male gonads (testicles) via meiotic division. The initial spermatozoon process takes around 70 days to complete. The process starts with the production of spermatogonia from germ cell precursors. These divide and differentiate into spermatocytes, which undergo meiosis to form spermatids.
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Polyembryoma is a rare, very aggressive form of germ cell tumor usually found in the ovaries. Polyembryoma has features of both yolk sac tumour and undifferentiated teratoma/embryonal carcinoma, with a characteristic finding of embryoid bodies lying in a loose mesenchymal stroma. It has been found in association with Klinefelter syndrome.
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In some multicellular groups, which are called Weismannists, a separation between a sterile somatic cell line and a germ cell line evolved. However, Weismannist development is relatively rare (e.g., vertebrates, arthropods, Volvox), as a great part of species have the capacity for somatic embryogenesis (e.g., land plants, most algae, many invertebrates).
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Choriocarcinoma is a malignant, trophoblastic cancer, usually of the placenta. It is characterized by early hematogenous spread to the lungs. It belongs to the malignant end of the spectrum in gestational trophoblastic disease (GTD). It is also classified as a germ cell tumor and may arise in the testis or ovary.
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Analysis of cancer transcriptome databases (www.ebi.ac.uk/gxa) showed that TEAD1 is dysregulated in several types of cancers. First in Kaposi sarcoma there is a 300-fold increase in TEAD1 levels. Moreover, the increase of TEAD expression can be detected in basal-like breast cancers, fallopian tube carcinoma, and germ cell tumors.
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The end-products of the germ cell cycle are the egg or sperm. Under special conditions in vitro germ cells can acquire properties similar to those of embryonic stem cells (ES). The underlying mechanism of that change is still unknown. These changed cells are then called embryonic germ cells (EG).
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RAI14 is predicted to play a role in cell-cell adhesion sites, particularly the cell-cell interactions of Sertoli cells from within the testis. Sertoli cells are involved in the creation of the blood testis barrier and provides a specialized, protected environment within the seminiferous tubules of the testis for germ cell development.
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Folliculogenesis-specific basic helix-loop-helix, also known as factor in the germline alpha (FIGalpha) or transcription factor FIGa, is a protein that in humans is encoded by the FIGLA gene. The FIGLA gene is a germ cell-specific transcription factor preferentially expressed in oocytes that can be found on human chromosome 2p13.3.
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According to this theory, the genomes contributed by the germ cell, sperm and egg contained a large repertoire of immunoglobulin genes. It was clear that there should be a mechanism that help the antibody to have diversity and keep it constant. The germ line theory could not provide any explanation on this aspect.
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This period consists of the primordial germ cells (PGC), the initial cells that commence germ cell development in the embryo, and the gonocytes, which after being differentiated from PGCs, undergo regulated proliferation, differentiation, migration and apoptosis to produce the SSCs. Gonocytes therefore correspond to the developmental stages between the PGCs and SSCs.
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The most common type is germ cell tumors which are divided into seminomas and nonseminomas. Other types include sex-cord stromal tumors and lymphomas. Diagnosis is typically based on a physical exam, ultrasound, and blood tests. Surgical removal of the testicle with examination under a microscope is then done to determine the type.
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The lineage of germ cells is called germ line. Germ cell specification begins during cleavage in many animals or in the epiblast during gastrulation in birds and mammals. After transport, involving passive movements and active migration, germ cells arrive at the developing gonads. In humans, sexual differentiation starts approximately 6 weeks after conception.
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In the Xenopus egg, the germ cell determinants are found in the most vegetal blastomeres. These presumptive PGCs are brought to the endoderm of the blastocoel by gastrulation. They are determined as germ cells when gastrulation is completed. Migration from the hindgut along the gut and across the dorsal mesentery then takes place.
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This protein has been shown to interact with and be involved in the phosphorylation of tumor suppressor protein Rb. Knockout studies of the homologous gene in mouse suggest the essential roles of this gene in ovarian granulosa and germ cell proliferation. High level expression of this gene was observed in ovarian and testicular tumors.
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Spermatogenesis-and-oogenesis-specific basic helix-loop-helix containing protein 1 (Sohlh1) is expressed within germ cell clusters and in new primordial follicles. Knock out studies of this protein in mice show a reduced number of oocytes present at 7 weeks post birth and a malfunction in the transition from primordial to primary follicle.
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Spermatocytic tumor is a rare tumour, making up only one to two percent of all testicular germ cell tumours. Men presenting with this tumour are generally 50 to 60 years old, and its occurrence is rare in men under 30 years old. Most present with slow, painless testicular enlargement, which may involve both testes.
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The number of germ cell divisions in females are constant and are much less than that in males. In females, most primary oocytes are formed at birth. The number of cell divisions occurred in the production of a mature ovum is constant. In males, more cell divisions are required during the process of spermatogenesis.
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There are at least four distinct but related alkaline phosphatases: intestinal, placental, placental-like, and liver/bone/kidney (tissue non-specific). The product of this gene is a membrane bound glycosylated enzyme, localized to testis, thymus and certain germ cell tumors, that is closely related to both the placental and intestinal forms of alkaline phosphatase.
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Several years later at the National Cancer Institute, Roy Hertz and Min Chiu Li then demonstrated complete remission in women with choriocarcinoma and chorioadenoma in 1956, discovering that methotrexate alone could cure choriocarcinoma (1958), a germ-cell malignancy that originates in trophoblastic cells of the placenta. In 1960 Wright et al. produced remissions in mycosis fungoides.
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In December 1999, while still writing for the album, Clayton-Felt was diagnosed with choriocarcinoma, a rare form of a particularly aggressive testicular cancer with the worst prognosis of all germ-cell cancers. He died a month later at the age of 32. Robert B. Weide delivered the eulogy at Clayton-Felt's funeral, in early 2000.
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Dysgerminoma is the most common type of malignant germ-cell ovarian cancer. Dysgerminoma usually occurs in adolescence and early adult life; about 5% occur in prepubertal children. Dysgerminoma is extremely rare after age 50. It occurs in both ovaries in 10% of patients and, in a further 10%, a microscopic tumor is in the other ovary.
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In the United States, it is also the fifth-most common cancer in women but the fourth-most common cause of cancer death. This decrease made it the ninth-most common cancer in women. The risks from developing specific types of ovarian cancer varies. Germ cell tumors and sex cord-stromal tumors are less common than epithelial tumors.
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Choriocarcinoma can occur as a primary ovarian tumor developing from a germ cell, though it is usually a gestational disease that metastasizes to the ovary. Primary ovarian choriocarcinoma has a poor prognosis and can occur without a pregnancy. They produce high levels of hCG and can cause early puberty in children or menometrorrhagia (irregular, heavy menstruation) after menarche.
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Mutations in Vasa homolog, Mvh, cause defects in spermatogenesis but females are fertile. Male sterility may be due to deficiencies in germ cell proliferation and differentiation (the mouse homolog of Droso.). Female fertility may be due to functional redundancy by other DEAD-box family members. Null mutation still allows primordial germ cells to form but have severe defects.
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Studies in Dp2 gene-deficient (i.e. Dp2−/-) mice indicate that DP2 is essential for controlling cell cycle genes in fetal testes which contribute to the arrest of mitotic process and to the differentiate of germ cells. This control involves, at least in part, the DP2-dependent activation of the male germ cell marker Nanos2 and the inhibition of meiosis through repression of Stra8.
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A alt= Teratoma are most common germ cell tumor of ovary .Teratomas can be divided into two types: mature teratoma (benign) and immature teratoma (malignant). Immature teratomas contain immature or embryonic tissue which significantly differentiates them from mature teratomas as they carry dermoid cysts. It is commonly observed in 15 to 19-year-old women and rarely in women after menopause.
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Overall, they metastasize more frequently than epithelial ovarian cancers. In addition, the cancer markers used vary with tumor type: choriocarcinomas are monitored with beta-HCG and endodermal sinus tumors with alpha-fetoprotein. Germ-cell tumors are typically discovered when they become large, palpable masses. However, like sex cord tumors, they can cause ovarian torsion or hemorrhage and, in children, isosexual precocious puberty.
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Three patients showed heterozygous de-novo missense mutation. Six patients were found with de-novo missense mutation and one patient was identified with de-novo splice site mutation. De novo mutation is a mutation that occurs in the germ cell of one parent. Neither parent has the mutation, but it is passed to the child through the sperm or egg.
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Ovarian germ cell tumors are common among teenagers and young women. It is a growth in the ovaries. Causes: Though the exact causes are not known, it may happen owing to certain birth defects affecting the genitals, nervous system or the urinary tract. There may be genetic conditions affecting the sex chromosomes that result in these kind of tumors as well.
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CFAP299 is widely expressed in a variety of normal tissue in Homo sapiens . CFAP299 is highly expressed in testis, trachea, lung, fetal lung and epididymis. In terms of health state, CFAP299 has a decreased expression level in glioma, germ cell tumors and chondrosarcoma. An even higher expression of CFAP299 is shown in condition of soft tissue tumor and muscle tissue tumor.
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Other less common primary patterns included nested (3%), micropapillary (2%), anastomosing glandular (1%), sieve-like glandular (<1%), pseudopapillary (<1%), and blastocyst-like (<1%). Testicular embryonal carcinoma occurs mostly (84%) as a component of a mixed germ cell tumor, but 16% are pure. Occasionally, embryonal carcinoma develops predominantly in the context of polyembryoma-like (6%) and diffuse embryoma-like ("necklace" pattern) (3%) proliferations.
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While nasal glial heterotopia (NGH) is the preferred term, synonyms have included nasal glioma. However, this term is to be discouraged, as it implies a neoplasm or tumor, which it is not. By definition, nasal glial heterotopia is a specific type of choristoma. It is not a teratoma, however, which is a neoplasm comprising all three germ cell layers (ectoderm, endoderm, mesoderm).
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There is no cure or treatment for testicular microlithiasis, however, patients may be monitored via ultrasound to make sure that other conditions do not develop. Emphasis on testicular examination is the recommended follow up for asymptomatic men incidentally identified with testicular microlithiasis. For men with risk factors for testicular germ cell tumor such as subfertility however, individualized discussion with their urologists is necessary.
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HER2 is colocalised and most of the time, coamplified with the gene GRB7, which is a proto-oncogene associated with breast, testicular germ cell, gastric, and esophageal tumours. HER2 proteins have been shown to form clusters in cell membranes that may play a role in tumorigenesis. Evidence has also implicated HER2 signaling in resistance to the EGFR-targeted cancer drug cetuximab.
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Most testicular germ cell tumors have too many chromosomes, and most often they are triploid to tetraploid. An isochromosome 12p (the short arm of chromosome 12 on both sides of the same centromere) is present in about 80% of the testicular cancers, and also the other cancers usually have extra material from this chromosome arm through other mechanisms of genomic amplification.
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Little is known about the chronic toxicity of diethyl phthalate, but existing information suggests only a low toxic potential. Studies suggest that some phthalates affect male reproductive development via inhibition of androgen biosynthesis. In rats, for instance, repeated administration of DEP results in loss of germ cell populations in the testis. However, diethyl phthalate doesn't alter sexual differentiation in male rats.
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Expressed Sequence Tag and microarray data suggests that Morn1 is expressed predominantly in the brain, eyes, lungs, parathyroid, salivary gland, testis, kidneys, trachea, and to a lesser extent the ovaries, prostate, thymus and the trachea. It is expressed in adults and in fetuses. By health state, Morn1 appears to be expressed in the normal state, as well as germ cell and kidney tumors.
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One of main function of Vasa protein is in germ cell determination and function. It uses ATP dependent RNA helicase catalytic activity to regulate the translation of multiple mRNAs. Vasa unwinds the duplex RNA by binding and bending short stretches of the duplex in a non-processive manner. The conserved domain may act as chaperones by unwinding RNA secondary structures and refolding properly.
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This gene is located in the nonrecombining portion of the Y chromosome, and expressed specifically in testis. The encoded protein interacts with ubiquitin protein ligase E3A and may be involved in male germ cell development and male infertility. Three nearly identical copies of this gene exist on chromosome Y; two copies are part of a palindromic region. This record represents the copy outside of the palindromic region.
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Unlike benign germ cell tumors of the mediastinum, malignant mediastinal tumors are usually symptomatic at the time of diagnosis. Most mediastinal malignant tumors are large and cause symptoms by compressing or invading adjacent structures, including the lungs, pleura, pericardium, and chest wall. Seminomas grow relatively slowly and can become very large before causing symptoms. Tumors 20 to 30 cm in diameter can exist with minimal symptomatology.
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Apart from those distinctions (preformationism-epigenesis and genetic- epigenetic), the terms preformistic development, epigenetic development and somatic embryogenesis are also used in another context, in relation to the differentiation of a distinct germ cell line. In preformistic development, the germ line is present since early development. In epigenetic development, the germ line is present, but it appears late. In somatic embryogenesis, a distinct germ line is lacking.
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Sertoli-Leydig cell tumors cause virilization and excessive hair growth due to the production of testosterone and androstenedione, which can also cause Cushing's syndrome in rare cases. Also, sex-cord stromal tumors occur that do not cause a hormonal imbalance, including benign fibromas, which cause ascites and hydrothorax. With germ cell tumors, sex cord-stromal tumors are the most common ovarian cancer diagnosed in women under 20.
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Tyrosine phosphorylation mediates in signal transduction pathways during germ cell development and determines their association with the differentiation of a functional gamete. Until testicular germ cells differentiate into spermatozoa, cAMP-induced tyrosine phosphorylation is not detectable. Entry of these cells into the epididymis is accompanied by sudden activation of the tyrosine phosphorylation pathway, initially in the principal piece of the cell and subsequently in the midpiece.
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Oogenesis is the formation of a cell who will produce one ovum and three polar bodies. Oogenesis begins in the female embryo with the production of oogonia from primordial germ cells. Like spermatogenesis, the primordial germ cell undergo mitotic division to form the cells that will later undergo meiosis, but will be halted at the prophase I stage. This is known as the primary oocyte.
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In this way, the Aub or Ago3 'responder' piRNA sequence cleaves a complementary target that is then sliced at periodic intervals of approximately 27 nucleotides that are sequentially loaded into Piwi protein. Once loaded with piRNA, Piwi then enters the germ cell nucleus to co-transcriptionally silence nascent transcripts with complementarity to its piRNA guide. It is currently unknown whether phasing occurs in other organisms.
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8-oxo-2'-deoxyguanosine (8-oxodG) is an oxidized derivative of deoxyguanosine, and is one of the major products of DNA oxidation. During DNA replication in the germ line of mice, the oxidized base 8-oxoguanine (8-oxoG) causes spontaneous and heritable G to T transversion mutations. These mutations occur in different stages of the germ cell lineage and are distributed throughout the chromosomes.
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In August Weismann's germ plasm theory, the hereditary material, the germ plasm, is confined to the gonads. Somatic cells (of the body) develop afresh in each generation from the germ plasm. Whatever may happen to those cells does not affect the next generation. The Weismann barrier, proposed by August Weismann in 1892, distinguishes between the "immortal" germ cell lineages (the germ plasm) which produce gametes and the "disposable" somatic cells.
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In humans, infertility is one of the characteristics of individuals with mutational defects in the FANC genes. In mice, spermatogonia, preleptotene spermatocytes, and spermatocytes in the meiotic stages of leptotene, zygotene and early pachytene are enriched for FANC proteins. This finding suggests that recombinational repair processes mediated by the FANC proteins are active during germ cell development, particularly during meiosis, and that defects in this activity can lead to infertility.
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Pure germinomas are not associated with these markers. Nongerminomatous germ-cell tumors may be associated with increased markers such as alpha-fetoprotein with yolk sac tumors, as well as embryonic cell carcinomas and immature teratomas and beta- HCG, which occur in choriocarcinomas. In one to 15% of germinomas, a low level of beta-HCG may be produced. Although controversial, HCG-secreting germinomas may be more aggressive than nonsecreting ones.
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There are five main subtypes of ovarian carcinoma, of which high-grade serous carcinoma (HGSC) is the most common. These ovarian tumors are believed to start in the cells covering the ovaries, though some may form at the Fallopian tubes. Less common types of ovarian cancer include germ cell tumorsand sex cord stromal tumors. A diagnosis of ovarian cancer is confirmed through a biopsy of tissue, usually removed during surgery.
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The monoclonal antibody farletuzumab is being researched as an adjuvant to traditional chemotherapy. Another type of immunotherapy involves vaccines, including TroVax. An alternative to BEP chemotherapy, a regimen of 3 cycles of carboplatin and etoposide, is a current topic of research for germ cell malignancies. Intraperitoneal chemotherapy has also been under investigation during the 2000s and 2010s for its potential to deliver higher doses of cytotoxic agent to tumors.
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Gonocytes are formed from the differentiation of PGCs. Embryonic cells initiate germ cell development in the proximal epiblast located near the extra-embryonic ectoderm by the release of bone morphogenetic protein 4 (BMP4) and BMP8b. These proteins specify embryonic cells into PGCs expressing the genes PRDM1 and PRDM14 at embryonic day (E) 6.25. The PGCs which are positively stained by alkaline phosphatase and expressing Stella at E7.25 are also specified.
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This gene encodes a nuclear envelope protein that appears to be involved in spermatogenesis, either directly or by influencing genes that play a more direct role in the process. This multi-exon locus is the homolog of the mouse and drosophila germ cell-less gene but the human genome also contains a single-exon locus on chromosome 5 that contains an open reading frame capable of encoding a highly related protein.
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Bosl is a specialist in the treatment of genitourinary tumors particularly in testicular cancer. He is known for targeting a marker chromosome for Germ cell tumors. His studies investigate molecular targets of drug resistance in patients and developing dose-intensive chemotherapy and new chemotherapeutic agents, evaluating new combinations for patients with relapsing or resistant disease.Ed Edelson Some of his research is also centered on new therapies for head and neck cancers.
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When a germ cell with an uneven number of chromosomes undergoes meiosis, the chromosomes cannot be evenly divided between the daughter cells, resulting in aneuploid gametes. Triploid organisms, for instance, are usually sterile. Because of this, triploidy is commonly exploited in agriculture to produce seedless fruit such as bananas and watermelons. If the fertilization of human gametes results in three sets of chromosomes, the condition is called triploid syndrome.
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QRICH1 is expressed at a high level, 3.3 times the average gene. It is expressed ubiquitously throughout the human body, although EST Profile data reveal that QRICH1 is expressed particularly high in tissues such as the thymus, testis, cerebellar cortex and other areas of the brain, trachea, and in embryonic tissue. Health states such as germ cell tumors, leukemia, lymphoma, and chondrosarcoma have also reported high QRICH1 expression.
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Shortening of the telomeres is a normal process in somatic cells. This shortens the telomeres of the daughter DNA chromosome. As a result, cells can only divide a certain number of times before the DNA loss prevents further division. (This is known as the Hayflick limit.) Within the germ cell line, which passes DNA to the next generation, telomerase extends the repetitive sequences of the telomere region to prevent degradation.
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About 10–15% of human couples are infertile, unable to conceive. In approximately in half of these cases, the underlying cause is related to the male. The underlying causative factors in the male infertility can be attributed to environmental toxins, systemic disorders such as, hypothalamic–pituitary disease, testicular cancers and germ-cell aplasia. Genetic factors including aneuploidies and single-gene mutations are also contributed to the male infertility.
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People with Down syndrome have a lower risk of all major solid cancers including those of lung, breast, cervix, with the lowest relative rates occurring in those aged 50 years or older. This low risk is thought due to an increase in the expression of tumor suppressor genes present on chromosome 21. One exception is testicular germ cell cancer which occurs at a higher rate in Down syndrome.
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Because this is a rare tumor, not many family physicians or oncologists are familiar with this disease. DSRCT in young patients can be mistaken for other abdominal tumors including rhabdomyosarcoma, neuroblastoma, and mesenteric carcinoid. In older patients DSRCT can resemble lymphoma, peritoneal mesothelioma, and peritoneal carcinomatosis. In males DSRCT may be mistaken for germ cell or testicular cancer while in females DSRCT can be mistaken for Ovarian cancer.
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SCD1 function has also been shown to be involved in germ cell determination, adipose tissue specification, liver cell differentiation and cardiac development. The human SCD-1 gene structure and regulation is very similar to that of mouse SCD-1. Overexpression of SCD-1 in humans may be involved in the development of hypertriglyceridemia, atherosclerosis, and diabetes. One study showed that SCD-1 activity was associated with inherited hyperlipidemia.
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In some organisms with a shorter generation time than humans, the mutation rate in males is also larger than those in females. Because their cell divisions in males are usually not that large. The ratio of the number of germ cell divisions from one generation to the next in males to females is less than that in human. There are also other hypotheses that want to explain the male mutation bias.
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A germ cell is any biological cell that gives rise to the gametes of an organism that reproduces sexually. In many animals, the germ cells originate in the primitive streak and migrate via the gut of an embryo to the developing gonads. There, they undergo meiosis, followed by cellular differentiation into mature gametes, either eggs or sperm. Unlike animals, plants do not have germ cells designated in early development.
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COG conducts research in children with medulloblastoma, ependymoma, brainstem gliomas, low and high-grade gliomas, and germ cell tumors. The large multi-site structure of COG also allows it to conduct research into very rare childhood cancer including retinoblastoma, hepatoblastoma, and other tumors. In addition to disease specific research, COG conducts studies in developmental therapeutics (new cancer drug development), supportive care, epidemiology, stem cell transplantation, behavioral sciences and survivorship.
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The epigenome may also be passed through the gametes. For this to occur, the epigenome must be present in the germline. The epigenome is also extensively reprogrammed during germ cell differentiation and after fertilization to create totipotent cells, erasing many changes that occur during an individual's lifetime. Therefore, the best candidates for heritable epigenetic marks are located at repeat/transposable sequences or regulatory elements that are resistant to reprogramming.
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A fourth type exists and is germ cell specific. In the early embryonic stages of the chick, the only lamins present are B-type lamins. In further stages, the expression pattern of lamin B1 decreases and there is a gradual increase in the expression of lamin A. Mammalian development seems to progress in a similar way. In the latter case as well it is the B-type lamins that are expressed in the early stages.
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The location of metastases may be a clue as to the underlying source, even if this cannot be found on investigations. For instance, a woman in whom there is axillary lymphadenopathy (swelling in the lymph nodes of the armpit) it is likely that the cancer originated in the breast, and men with lymph node deposits in the mediastinum of the chest and/or retroperitoneal space of the abdomen may have a germ cell tumor.
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Soon after the release of The Gathering, lead guitarist James Murphy was diagnosed with a brain tumor. Through various fundraisers, Murphy was able to afford surgery and eventually made a full recovery, but was unable to recall anything from the recording of The Gathering. In 2001, Chuck Billy was also diagnosed with germ cell seminoma, a rare form of testicular cancer, but it only affected Billy's lungs and heart. His cancer was also treated successfully.
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He took the role of Galileo in the Edinburgh Playhouse production of We Will Rock You in part because he had not been to Edinburgh before and wished to see the city. In 2019, Falzon was diagnosed and began treatment for a rare and aggressive form of germ cell cancer, causing him to cancel all appearances for the remainder of the year. Falzon died from cancer on 23 June 2020, aged 48.
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Evidence for causing these cancers is mixed concerning heavy, long-term use. In general there are far lower risks of pulmonary complications for regular cannabis smokers when compared with those of tobacco. A 2015 review found an association between cannabis use and the development of testicular germ cell tumors (TGCTs), particularly non-seminoma TGCTs. Another 2015 meta-analysis found no association between lifetime cannabis use and risk of head or neck cancer.
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Cases of the disease not associated with mediastinal germ cell tumors occur in adults who as a group have older median age centering around those 50–70 years old. The disorder is far more fulminant than non-DS-AMKL and DS-AMKL and generally presents with more serious hematological symptoms (e.g. anemia- related) and a much higher incidence of extramedullary manifestations (e.g. organ enlargement, leukemia cutis) than seen in the other two forms of AMKL.
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Levin described a qualitative method of assessing testis histologic patterns that is commonly used clinically to assess testis pathology in male infertility. Recognized patterns include: normal spermatogenesis, hypoplasia or hyposperm¬ato¬genesis, complete or early maturation arrest, Sertoli cell-only or germ cell aplasia, incomplete or late maturation arrest, and sclerosis.Levin HS. Testicular biopsy in the study of male infertility: its current usefulness, histologic techniques, and prospects for the future. Hum Pathol 1979;10:569-84.
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The cause is unknown, but this condition has been associated with testicular cancer in a small group of individuals, cryptorchidism, mumps, infertility and intraepithelial germ cell neoplasia. Classic testicular microlithiasis is defined as five or more echogenic foci per view in either or both testes, and limited testicular microlithiasis defined as one or more echogenic foci that do not satisfy the criteria for classic testicular microlithiasis. In 80% of cases, both testicles are affected.
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It has been demonstrated that endogenous HOOK3 binds to Golgi membranes, whereas both HOOK1 and HOOK2 are localised to discrete but unidentified cellular structures. In mice the Hook1 gene is predominantly expressed in the testis. Hook1 function is necessary for the correct positioning of microtubular structures within the haploid germ cell. Disruption of Hook1 function in mice causes abnormal sperm head shape and fragile attachment of the flagellum to the sperm head.
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To work around this, several studies have used more accessible sources, like lymphocytes or germ cell lines, since some studies have shown that epigenetic mutations can be detected in other tissues. Epigenetic studies of disorders like schizophrenia are also subject to the subjectivity of psychiatric diagnoses and the spectrum-like nature of mental health problems. This problem with classification of mental health problems have led to intermediate phenotypes that might be better fit.
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Cisplatin is administered intravenously as short-term infusion in normal saline for treatment of solid and haematological malignancies. It is used to treat various types of cancers, including sarcomas, some carcinomas (e.g., small cell lung cancer, squamous cell carcinoma of the head and neck and ovarian cancer), lymphomas, bladder cancer, cervical cancer, and germ cell tumors. Cisplatin is particularly effective against testicular cancer; its adoption has increased the cure rate from 10% to 85%.
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The most common brain tumor types in children (0-14) are: pilocytic astrocytoma, malignant glioma, medulloblastoma, neuronal and mixed neuronal- glial tumors, and ependymoma. In children under 2, about 70% of brain tumors are medulloblastomas, ependymomas, and low-grade gliomas. Less commonly, and seen usually in infants, are teratomas and atypical teratoid rhabdoid tumors. Germ cell tumors, including teratomas, make up just 3% of pediatric primary brain tumors, but the worldwide incidence varies significantly.
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Epigenetic upregulation of the DNA repair genes PARP1 and FEN1 occurs in numerous cancers (see Regulation of transcription in cancer). PARP1 and FEN1 are essential genes in the error-prone and mutagenic DNA repair pathway microhomology- mediated end joining. If this pathway is upregulated, the excess mutations it causes can lead to cancer. PARP1 is over-expressed in tyrosine kinase- activated leukemias, in neuroblastoma, in testicular and other germ cell tumors, and in Ewing's sarcoma.
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The average age of diagnosis is between 35 and 50 years. This is about 5 to 10 years older than men with other germ cell tumors of the testes. In most cases, they produce masses that are readily felt on testicular self-examination; however, in up to 11 percent of cases, there may be no mass able to be felt, or there may be testicular atrophy. Testicular pain is reported in up to one fifth of cases.
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Formal visual field testing by perimetry is recommended, as this would show evidence of optic nerve compression by a tumor. Other tests that may assist in the diagnosis of hypopituitarism, especially if no tumor is found on the MRI scan, are ferritin (elevated in hemochromatosis), angiotensin converting enzyme (ACE) levels (often elevated in sarcoidosis), and human chorionic gonadotropin (often elevated in tumor of germ cell origin). If a genetic cause is suspected, genetic testing may be performed.
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PALB2 mutant male mice have reduced fertility. This reduced fertility appears to be due to germ cell attrition resulting from a combination of unrepaired DNA breaks during meiosis and defective synapsis of the X and Y chromosomes. The function of homologous recombination during meiosis appears to be repair of DNA damages, particularly double-strand breaks (also see Origin and function of meiosis). The PALB2-BRCA1 interaction is likely important for repairing such damages during male meiosis.
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Schematic diagram illustrating the pathogenic links that lead to TDS. CIS = carcinoma in situ; GC = Germ CellThe TDS hypothesis proposes that testicular dysgenesis, which has various primary causes, can lead to abnormalities in Sertoli and/or Leydig cell function. This leads to both impaired germ cell development and hormonal changes during male sexual differentiation. For instance, insufficient production of testosterone can result in incomplete masculinisation, whilst reduced expression of insulin-like factor 3 can lead to incomplete testes descent.
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Balbiani is known for his work in microbiology as well as his studies in embryology. He is credited with the discovery of sexual organ development in Chironomus which eventually led to the general theory on the autonomy of the germ cell. Also, he conducted comprehensive biological research on the sexual habits of Phylloxera vastatrix. Science, Vine and Wine in Modern France by Harry W. Paul With anatomist Louis-Antoine Ranvier (1835-1922), he founded the Archives d'anatomie microscopique.
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Specifically, Wnt3 leads to mesoderm committed cells with hematopoietic potential. Wnt1 antagonizes neural differentiation and is a major factor in self-renewal of neural stem cells. This allows for regeneration of nervous system cells, which is further evidence of a role in promoting neural stem cell proliferation. Wnt signaling is involved in germ cell determination, gut tissue specification, hair follicle development, lung tissue development, trunk neural crest cell differentiation, nephron development, ovary development and sex determination.
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An uncle who was a doctor in Fuzhou funded Cheng's travel and he chose the University of Michigan as a cousin studied there. He studied under Peter Olas Okkelberg and received a doctorate in 1930 for his thesis on "The Germ Cell history of Rana cantabrigensis Baird". He also received a Sigma Xi golden Key award. While in the US he had visited the natural history of the museum and had wondered about a golden pheasant specimen.
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Cleavage and division of the cell of an egg of a vertebrate (Remak, 1855). Caspar Friedrich Wolff observed organization of the early embryo in leaf-like layers. In 1817, Heinz Christian Pander discovered three primordial germ layers while studying chick embryos. Between 1850 and 1855, Robert Remak had further refined the germ cell layer (Keimblatt) concept, stating that the external, internal and middle layers form respectively the epidermis, the gut, and the intervening musculature and vasculature.
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PARP1 is over-expressed in tyrosine kinase-activated leukemias, in neuroblastoma, in testicular and other germ cell tumors, and in Ewing's sarcoma, FEN1 is over- expressed in the majority of cancers of the breast, prostate, stomach, neuroblastomas, pancreatic, and lung. DNA damage appears to be the primary underlying cause of cancer. If accurate DNA repair is deficient, DNA damages tend to accumulate. Such excess DNA damage can increase mutational errors during DNA replication due to error-prone translesion synthesis.
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Additionally, there is a reciprocal relationship to that of TAF7 expression: Unlike TAF7l, TAF7 at early stages is expressed in the nucleus, and thus separated from TAF7l. Then, at later stages, when TAF7l transitions into the nucleus, which happens around the time when the somatic (diploid) to germ cell (haploid) transition occurs, TAF7 dramatically declines. This may indicate that TAF7l plays an important role in regulating the TFIID during development of the sperm. Pointud et al.
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If this pathway is over-expressed, the excess mutations it causes can lead to cancer. PARP1 is over-expressed in tyrosine kinase-activated leukemias, in neuroblastoma, in testicular and other germ cell tumors, and in Ewing's sarcoma, FEN1 is over-expressed in the majority of cancers of the breast, prostate, stomach, neuroblastomas, pancreatic, and lung. DNA damage appears to be the primary underlying cause of cancer. If accurate DNA repair is deficient, DNA damages tend to accumulate.
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There is also evidence that telomerase activity is increased in tissues, such as germ cell lines, that are self-renewing. Normal somatic cells, on the other hand, do not have detectable telomerase activity. Since the catalytic component of telomerase is its reverse transcriptase, hTERT, and the RNA component hTERC, hTERT is an important gene to investigate in terms of cancer and tumorigenesis. The hTERT gene has been examined for mutations and their association with the risk of contracting cancer.
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If mutations disable the lag gene, large cells specified by glsA will develop as somatic cells initially but then de-differentiate to become gonidia. Determination of somatic cells is controlled by the transcription factor regA. The regA geneencodes a single 80 amino acid-long DNA-binding SAND domain that is expressed in somatic cells after embryonic development. regA acts to prevent division by inhibiting cell growth via downregulation of chloroplast biosynthesis, and represses expression of genes necessary for germ cell formation.
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There are signs and symptoms of extracranial germ- cell tumor that can be seen in children, adolescents, or young adults. These symptoms include fever, constipation, abnormal bleeding in vagina and miss menstruation in females, a lump in the testes in males, lumps along the midline of the body, include coccyx, neck, and abdomen. The symptoms of EGCTs appear differently by the location of it. According to the symptoms and location of the EGCTs, specialists may diagnose the type of the tumor.
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These cells can form group organisms through cell adhesion. The individual members of a colony are capable of surviving on their own, whereas the members of a true multi- cellular organism have developed specializations, making them dependent on the remainder of the organism for survival. Such organisms are formed clonally or from a single germ cell that is capable of forming the various specialized cells that form the adult organism. This specialization allows multicellular organisms to exploit resources more efficiently than single cells.
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In germline gene therapy (GGT), germ cells (sperm or egg cells) are modified by the introduction of functional genes into their genomes. Modifying a germ cell causes all the organism's cells to contain the modified gene. The change is therefore heritable and passed on to later generations. Australia, Canada, Germany, Israel, Switzerland, and the Netherlands prohibit GGT for application in human beings, for technical and ethical reasons, including insufficient knowledge about possible risks to future generations and higher risks versus SCGT.
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1001427 An analysis of methylation profiles of humans and primate sperm cells reveals epigenetic regulation plays an important role here as well. Since mammalian cells undergo reprogramming of DNA methylation patterns during germ cell development, the methylomes of human and chimp sperm can be compared to methylation in embryonic stem cells (ESCs). There were many hypomethylated regions in both sperms cells and ESCs that showed structural differences. Also, many of the promoters in human and chimp sperm cells had different amounts of methylation.
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Intracranial germinoma occurs in 0.7 per million children. As with other germ-cell tumors (GCTs) occurring outside the gonads, the most common location of intracranial germinoma is on or near the midline, often in the pineal or suprasellar areas; in 5-10% of patients with germinoma in either area, the tumor is in both areas. Like other GCTs, germinomas can occur in other parts of the brain. Within the brain, this tumor is most common in the hypothalamic or hypophyseal regions.
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Chemotherapy is curative in approximately 20% of advanced ovarian cancers; it is more often curative with malignant germ cell tumors than epithelial tumors. Adjuvant chemotherapy has been found to improve survival and reduce the risk of ovarian cancer recurring compared to no adjuvant therapy in women with early stage epithelial ovarian cancer. Chemotherapy in ovarian cancer typically consists of platins, a group of platinum-based drugs, combined with non-platins. Common therapies can include paclitaxel, cisplatin, topotecan, doxorubicin, epirubicin, and gemcitabine.
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Very few studies used gonocytes to also refer to the female germ cells in the ovarium primordium. The specification of gonocytes to be confined to male germ cells occurred after foundational differences between the mechanisms of male and female fetal germ cells were uncovered. Some scientists prefer the terms “prospermatogonia” and “prespermatogonia” for their functional clarity. Later studies found that the process from primordial germ cell to spermatogonial development is gradual, without clear gene expression markers to distinguish the precursor cells.
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The life of a hornwort starts from a haploid spore. In most species, there is a single cell inside the spore, and a slender extension of this cell called the germ tube germinates from the proximal side of the spore. The tip of the germ tube divides to form an octant (solid geometry) of cells, and the first rhizoid grows as an extension of the original germ cell. The tip continues to divide new cells, which produces a thalloid protonema.
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Oncofetal antigens are proteins which are typically present only during fetal development but are found in adults with certain kinds of cancer. These proteins are often measurable in the blood of individuals with cancer and may be used to both diagnose and follow treatment of the tumors. One example of an oncofetal antigen is alpha-fetoprotein, which is produced by hepatocellular carcinoma and some germ cell tumors. Another example is carcinoembryonic antigen, which is elevated in people with colon cancer and other tumors.
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It is speculated that induction was the ancestral mechanism, and that the preformistic, or inheritance, mechanism of germ cell establishment arose from convergent evolution. There are several key differences between these two mechanisms that may provide reasoning for the evolution of germ plasm inheritance. One difference is that typically inheritance occurs almost immediately during development (around the blastoderm stage) while induction typically does not occur until gastrulation. As germ cells are quiescent and therefore not dividing, they are not susceptible to mutation.
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KIT is a proto-oncogene, meaning that overexpression or mutations of this protein can lead to cancer. Seminomas, a subtype of testicular germ cell tumors, frequently have activating mutations in exon 17 of KIT. In addition, the gene encoding KIT is frequently overexpressed and amplified in this tumor type, most commonly occurring as a single gene amplicon. Mutations of KIT have also been implicated in leukemia, a cancer of hematopoietic progenitors, melanoma, mast cell disease, and gastrointestinal stromal tumors (GISTs).
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GRB7 is an SH2-domain adaptor protein that binds to receptor tyrosine kinases and provides the intra-cellular direct link to the Ras proto-oncogene. Human GRB7 is located on the long arm of chromosome 17, next to the ERBB2 (alias HER2/neu) proto-oncogene. These two genes are commonly co-amplified (present in excess copies) in breast cancers. GRB7 thought to be involved in migration , is well known to be over-expressed in testicular germ cell tumors, esophageal cancers, and gastric cancers.
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Jose stopped competing after the match with Fickett as he started to show cardiovascular problems and was later diagnosed with germ cell cancer. He passed away from the cancer in 2011. Cortez got a tattoo in remembrance of her brother on her arm. She struggled through depression after her brother's passing but managed to get back in track with the help of her family and Henry Cejudo and Angel Cejudo, who are the best friends of her oldest brother Jose.
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The mediastinum has three main parts: the anterior mediastinum (front), the middle mediastinum, and the posterior mediastinum (back). Masses in the anterior portion of the mediastinum can include thymoma, lymphoma, pheochromocytoma, germ cell tumors including teratoma, thyroid tissue, and parathyroid lesions. Masses in this area are more likely to be malignant than those in other compartments. Masses in the posterior portion of the mediastinum tend to be neurogenic in origin, and in adults tend to be of neural sheath origin including neurilemomas and neurofibromas.
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In 1999, Hans Schöler left Germany to assume a professorship for Reproductive Physiology at the School of Veterinary Medicine University of Pennsylvania, USA. At the same time, he was director of the Center for Animal Transgenesis and Germ Cell Research at the University of Pennsylvania, Philadelphia, USA. From 2000 until 2004, Schöler held the Marion Dilley and David George Jones Chair for Reproductive Medicine. Since 2004, Hans Schöler has been director of the Department Cell and Developmental Biology Max Planck Institute for Molecular Biomedicine, Münster.
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Furthermore, the basal Sertoli-Sertoli cell junctions and the apical Sertoli-germ cell junctions contain myosin VIIA but lack its counterpart vezatin. Myosin VIIA is almost always expressed with vezatin but the absence of this partnership within the testis is yet to be fully understood. However, vezatin has been shown to be expressed within the acrosomal region of the actual spermatozoa. Vezatin is not found in the early spermatid but only appears when the formation of the acrosome occurs later on in the process of spermatogenesis.
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In Heliothis virescens, juvenile hormone (JH, which regulates many aspects of insect development) is necessary for the deposition of nutrients into the female germ cell, or yolk formation (vitellogenesis). It is thought that mating can enhance egg maturation, increase egg production, and induce oviposition due to stimulation of JH production. Mating was correlated with a surge in JH production by the corpus allatum in females - a 5 to 15 fold increase compared to virgin females, an allototropic effect. Juvenile hormone released by mated females increased 2.5 fold.
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Chicken primordial germ cells are initially specified in the area pellucida (a one-cell thick layer of epiblast lying above the sub-germinal space). Following the formation of the primitive streak, the germ cells are carried to the germinal crescent region. Unlike most model organisms where germ cell migration is predominantly via the gut epithelium, chicken PGCs migrate through the embryonic vascular epithelium. Once they have exited the capillary vessels, the final stage of migration is along the dorsal mesentery to the developing gonad.
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This gene belongs to the DAZ gene family required for germ cell development. It encodes an RNA-binding protein which is more similar to Drosophila Boule than to human proteins encoded by genes DAZ (deleted in azoospermia) or DAZL (deleted in azoospermia-like). Loss of this gene function results in the absence of sperm in semen (azoospermia). Histological studies demonstrated that the primary defect is at the meiotic G2 / M transition in fruitfly but in mice the primary defect is postmeiotic at round spermatid stage.
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Breuer found that Pappenheim's symptoms—headaches, excitement, curious vision disturbances, partial paralyses, and loss of sensation,Peter Gay, Freud: A Life for our Time (London 1988) p. 65 which had no organic origin and are now called somatoform disorders—improved once the subject expressed her repressed trauma and related emotions, a process later called catharsis. Peter Gay considered that, "Breuer rightly claimed a quarter of a century later that his treatment of Bertha Pappenheim contained 'the germ cell of the whole of psychoanalysis'."Gay, p.
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Depending on the extent of the cancer, procedures may include a bilateral salpingo- oophorectomy, biopsies throughout the peritoneum and abdominal lymphatic system, omentectomy, splenectomy, bowel resection, diaphragm stripping or resection, appendectomy, or even a posterior pelvic exenteration. To fully stage ovarian cancer, lymphadenectomy can be included in the surgery, but a significant survival benefit to this practice may not happen. This is particularly important in germ cell tumors because they frequently metastasize to nearby lymph nodes. If ovarian cancer recurs, secondary surgery is sometimes a treatment option.
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An endogenous viral element (EVE) is a DNA sequence derived from a virus, and present within the germline of a non-viral organism. EVEs may be entire viral genomes (proviruses), or fragments of viral genomes. They arise when a viral DNA sequence becomes integrated into the genome of a germ cell that goes on to produce a viable organism. The newly established EVE can be inherited from one generation to the next as an allele in the host species, and may even reach fixation.
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This gene product is a serine/threonine protein kinase that contains an N-terminal protein kinase domain and a C-terminal proline-rich domain. Its protein kinase domain is most closely related to those of the LIM motif-containing protein kinases (LIMKs). The encoded protein can phosphorylate myelin basic protein and histone in vitro. The testicular germ cell-specific expression and developmental pattern of expression of the mouse gene suggests that this gene plays an important role at and after the meiotic phase of spermatogenesis.
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Ovulation Induced ovulation is when a female animal ovulates due to an externally-derived stimulus during, or just prior, to mating, rather than ovulating cyclically or spontaneously. Stimuli causing induced ovulation include the physical act of coitus or mechanical stimulation simulating this, sperm and pheromones. Ovulation occurs at the ovary surface and is described as the process in which an oocyte (female germ cell) is released from the follicle. Ovulation is a non-deleterious 'inflammatory response' which is initiated by a luteinizing hormone (LH) surge.
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Surani co-discovered mammalian genomic imprinting with Davor Solter in 1984, and subsequently examined its mechanism and the functions of imprinted genes. He later established the genetic basis for germ cell specification, using a single-cell analysis in mice. This genetic network also initiates the unique resetting of the germline epigenome, including comprehensive erasure of DNA methylation towards re-establishing full genomic potency. Epigenetic modifications and re-establishments of imprints then generate functional differences between parental genomes whilst aberrant imprints contribute to human disease.
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The haploid number (n) refers to the total number of chromosomes found in a gamete (a sperm or egg cell produced by meiosis in preparation for sexual reproduction). Under normal conditions, the haploid number is exactly half the total number of chromosomes present in the organism's somatic cells. For diploid organisms, the monoploid number and haploid number are equal; in humans, both are equal to 23. When a human germ cell undergoes meiosis, the diploid 46-chromosome complement is split in half to form haploid gametes.
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Koopman's early work with Anne McLaren spawned an interest in the regulation of the germ cells during fetal development—cells that later become sperm or oocytes. His group discovered that the vitamin A metabolite retinoic acid stimulates germ cells to enter meiosis, a critical step in the formation of gametes. They also demonstrated that the developmental signaling molecule Nodal and its receptor Cripto regulate male germ cell pluripotency in the fetal gonad, opening the way for new non-invasive diagnostics and targeted additional therapies for testicular cancers.
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The initial acquisition of microbiota in animals from mammalians to marine sponges is at birth, and may even occur through the germ cell line. In plants, the colonizing process can be initiated below ground in the root zone, around the germinating seed, the spermosphere, or originate from the above ground parts, the phyllosphere and the flower zone or anthosphere. The stability of the rhizosphere microbiota over generations depends upon the plant type but even more on the soil composition, i.e. living and non living environment.
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Plants and basal metazoans such as sponges (Porifera) and corals (Anthozoa) do not sequester a distinct germline, generating gametes from multipotent stem cell lineages that also give rise to ordinary somatic tissues. It is therefore likely that germline sequestration first evolved in complex animals with sophisticated body plans, i.e. bilaterians. There are several theories on the origin of the strict germline-soma distinction. Setting aside an isolated germ cell population early in embryogenesis might promote cooperation between the somatic cells of a complex multicellular organism.
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The shell valves then open along the suture line and the binucleate germ cell penetrates between the intestinal epithelial cells of the worm. This cell multiplies, producing many amoeboid cells by an asexual cell fission process called merogony. As a result of the multiplication process, the intercellular space of the epithelial cells in more than 10 neighbouring worm segments may become infected. Around 60–90 days postinfection, sexual cell stages of the parasite undergo sporogenesis, and develop into pansporocysts, each of which contains eight triactinomyxon-stage spores.
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After female (XX) germ cells collect in the undifferentiated gonads, the up-regulation of Stra8 is required for germ cell differentiation into an oogonium and eventually enter meiosis. One major factor that contributes to the up-regulation of Stra8, is the initiation of the β-Catenin signaling pathway via RSPO1, which is also responsible for ovary differentiation. Since RSPO1 is produced in somatic cells, this protein acts on germ cells in a paracrine mode. Rspo1, however, is not the only factor in Stra8 regulation.
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Thrash of the Titans concert poster Thrash of the Titans was a benefit concert held on August 11, 2001 at the Maritime Hall in San Francisco, California. The concert was a co-benefit for Testament vocalist Chuck Billy, who was diagnosed with germ cell seminoma (a rare form of cancer); and Chuck Schuldiner, leader of the death metal band Death, who was also battling cancer. The Master of Ceremonies for the evening was S.O.D. vocalist Billy Milano. The concert was organized by Walter Morgan.
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Protein DGCR6 is a protein that in humans is encoded by the DGCR6 gene. DiGeorge syndrome, and more widely, the CATCH 22 syndrome, are associated with microdeletions in chromosomal region 22q11.2. This gene product shares homology with the Drosophila melanogaster gonadal protein, which participates in gonadal and germ cell development, and with the human laminin gamma-1 chain, which upon polymerization with alpha- and beta-chains forms the laminin molecule. Laminin binds to cells through interaction with a receptor and has functions in cell attachment, migration, and tissue organization during development.
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The piwi domain of an argonaute protein with bound siRNA, components of the RNA-induced silencing complex that mediates gene silencing by RNA interference. All human Piwi proteins and 440x440px Piwi-piRNA interactions: Within the nucleus, this pathway is involved in DNA methylation (A), histone methylation of H3K9 through interactions with heterochromatin protein 1 (HP1) and H3K9 histone methyltransferase (B). The Piwi-piRNA pathway also interacts with the elF translational initiator (C). Piwi (or PIWI) genes were identified as regulatory proteins responsible for stem cell and germ cell differentiation.
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A germ-cell mutation occurred in a male Persian cat called Treker in 1995, resulting in diminutive, but healthy and normally-proportioned, offspring. Treker and the females with which he was mated were normally sized, but 75% of the kittens sired by Treker inherited diminutive stature, but of normal proportions. The gene was found to be dominant and the diminutive offspring were sold as teacup or toy Persians. Teacup/Toy Persians are a separate breed and not all cats advertised under those names result from Treker's dominant mutation.
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Since a gene duplication occurs in only one cell, either in a single-celled organism or in the germ cell of a multi-cellular organism, its carrier (i.e. the organism) usually has to compete against other organisms that do not carry the duplication. If the duplication disrupts the normal functioning of an organism, the organism has a reduced reproductive success (or low fitness) compared to its competitors and will most likely die out rapidly. If the duplication has no effect on fitness, it might be maintained in a certain proportion of a population.
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CCCTC-binding factor (CTCF), an 11-zinc finger factor involved in gene regulation, utilizes different zinc fingers to bind varying DNA target sites. CTCF forms methylation-sensitive insulators that regulate X-chromosome inactivation. Transcriptional repressor CTCFL (this protein) is a paralog of CTCF and appears to be expressed primarily in the cytoplasm of spermatocytes, unlike CTCF which is expressed primarily in the nucleus of somatic cells. CTCF and CTCFL are normally expressed in a mutually exclusive pattern that correlates with resetting of methylation marks during male germ cell differentiation.
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In somatic cell gene therapy (SCGT), the therapeutic genes are transferred into any cell other than a gamete, germ cell, gametocyte, or undifferentiated stem cell. Any such modifications affect the individual patient only, and are not inherited by offspring. Somatic gene therapy represents mainstream basic and clinical research, in which therapeutic DNA (either integrated in the genome or as an external episome or plasmid) is used to treat disease. Over 600 clinical trials utilizing SCGT are underway in the US. Most focus on severe genetic disorders, including immunodeficiencies, haemophilia, thalassaemia, and cystic fibrosis.
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Some have hypothesized that the decreased bone mineral density observed in women with CAIS is related to the timing of gonadectomy and inadequate estrogen supplementation. However, recent studies show that bone mineral density is similar whether gonadectomy occurs before or after puberty, and is decreased despite estrogen supplementation, leading some to hypothesize that the deficiency is directly attributable to the role of androgens in bone mineralization. CAIS is also associated with an increased risk for gonadal tumors (e.g. germ cell malignancy) in adulthood if gonadectomy is not performed.
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Mutations in Pten, CyclinD1, Dmrt1 and Dnd1 oncogenes in mice resulted in testicular teratomas, and variants are related with the same tumours in humans. Tumour formation (neoplasm) from foetal gonocytes suggests that they are incapable of maintaining proliferative arrest and resistance to further differentiation. Even so, the origin of these teratomas could be distinct from the PGCs failing in migration. Extragonadal germ cell tumours (GCTs) evolve due to a lesion along the midline of the body, prior to the migratory PGCs movement through the hindgut and the medial mesentery to the gonads.
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Later in life, if the affected individual decides they want biological children, their tissue can be retrieved from a tissue bank. Another cause of male infertility is Klinefelter syndrome. This is a chromosomal abnormality (XY individual with extra X chromosomes) which causes germ cell loss early in life. Current research suggests that cryopreserving testicular tissue for prepubertal individuals can have promising results for using the tissue to produce sperm later in life, but is less likely to be effective if the testicular tissue is taken from older individuals.
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In most mammals, specification occurs first, followed by migration, and then the proliferation process begins in the gonads. PGCs interact with a wide range of cell types as they move from the epiblast to the gonads. The PGCs move passively (without the need for energy) with underlying somatic cells, cross epithelial barriers, and respond to cues from their environment during active migration. An epithelium must be crossed in many species during germ cell migration, and changes in adhesion are observed in PGCs during their exit from the endoderm and during the initiation of active migration.
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Thus, the knockout model shows that loss of the DMRT1 gene is associated with incomplete germ cell development leading to infertility, abnormal testicular formation, and/or feminization of the affected individual. Induced knockout of DMRT1 in adult male mice has been found to cause transdifferentiation of somatic cells in the testis to the equivalent cell types that would ordinarily be found in the ovary. Conversely, conditional expression of DMRT1 in the gonad of female mice caused the apparent transdifferentiation of ovarian somatic (granulosa) cells to the equivalent cell type (Sertoli) ordinarily found in males.
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Dysgerminomas, in particular, tend to affect both ovaries: 8–15% of dysgerminomas are present in both ovaries. People with low- grade (well-differentiated) tumors are typically treated only with surgery, which is often curative. In general, germ cell tumors can be treated with unilateral surgery unless the cancer is widespread or fertility is not a factor. In women with surgically staged advanced epithelial ovarian cancer (stages III and IV), studies suggest all attempts should be made to reach complete cytoreduction (surgical efforts to remove the bulk of the tumor).
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In contrast, eukaryotes, both unicellular and multicellular such as Amoeba dubia and humans (Homo sapiens) respectively, have much larger genomes (see C-value paradox). Amoeba dubia has a genome of 700 billion nucleotide pairs spread across thousands of chromosomes. Humans contain fewer nucleotide pairs (about 3.2 billion in each germ cell - note the exact size of the human genome is still being revised) than A. dubia however their genome size far outweighs the genome size of individual bacteria. The first bacterial and archaeal genomes, including that of H. influenzae, were sequenced by Shotgun sequencing.
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During approximately the same time, WNT3 starts to be expressed in the posterior visceral endoderm of the epiblast. WNT3 signalling has been shown to be essential in order for the epiblast to acquire responsiveness to the BMP4 signal from the ExE. WNT3 mutants fail to establish a primordial germ cell population, but this can be restored with exogenous WNT activity. The WNT3/β-catenin signalling pathway is essential for the expression of the transcription factor T (Brachyury), a transcription factor that is was previously characterized somatic and mesoderm specific genes.
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Studies have shown that AFP-L3% test results of more than 10% can be indicative of early HCC or early nonseminomatous germ cell tumor. Early testimonials from hepatologists indicate that there is a target patient population for the AFP-L3% assay. This target population are those CLD patients who have AFP concentrations in the indeterminate range of 20-200+ ng/mL and a small or indeterminate mass on imaging. It is in this range that doctors experience trouble differentiating non-HCC fluctuations in AFP vs indication of HCC.
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Nominal expression of PTCHD4 was found in the brain, connective tissue, embryonic tissue, lungs, placenta, testis, trachea, and uterus, with the greatest expression in the trachea. Nominal expression was also found in the following disease states: chondrosarcoma, germ cell tumors, non-neoplasia, and uterine tumors. Protein localization was found in all tissues examined except the salivary glands, yet RNA expression was scarcely found anywhere. This may suggest that PTCHD4 protein is particularly resilient to degradation, and that it is only produced under key circumstances or at key life stages.
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JAM-3 has been shown to be a primary regulator of the development of spermatids as well as the rest of the male reproductive system. Within the Sertoli cells of the male reproductive system, JAM-3 interacts with JAM-2 to influence the polarity of both round and elongated spermatids. JAM-1 and JAM-2 are also present in and contribute to the polarity of the blood-testis barrier. Studies have also shown that inactivation of JAM-3 has been shown to significantly impede fertility by blocking male germ cell development and proliferation.
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With her research, Anne Ephrussi has contributed to the elucidation of the crucial role that spatial and temporal control of mRNA localization and translation play in oocyte development and cell polarity. Dr. Ephrussi established that oskar RNA is accumulated at and thereby defines the posterior pole of the Drosophila oocyte. Aberrant localization and translation leads to germ cell formation defects and mispatterning during development. Proper localization of oskar mRNA is ensured by concerted actions of the exon junction complex and oskar's 3’ UTR followed by a microtubule-based movement.
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Germ cells are specified early in development and can only differentiate into gametes. The segregation of germ cells is often determined by the species, with some undergoing preformation, where the germ cells are determined by maternally inherited factors before or immediately after fertilisation, and others undergoing epigenesis, where the germ cell lineage is determined from signalling from surrounding tissues. Preformation was initially perceived as more common than epigenesis, as it appears in many model organisms like the common fruit fly, roundworms and some amphibians. Epigenesis has since been shown to be the more common mechanism.
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In mammals, the Y chromosome directs the development of the testes and plays an important role in spermatogenesis. A high percentage of infertile men have deletions that map to regions of the Y chromosome. The DAZ1 (Deleted in Azoospermia) gene cluster maps to the AZFc region of the Y chromosome and is deleted in many azoospermic and severely oligospermic men. It is thought that the DAZ gene cluster arose from the transposition, amplification, and pruning of the ancestral autosomal gene DAZL also involved in germ cell development and gametogenesis.
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He has also been studying the pluripotency mechanism and germ cell biology. He has also been making numerous contributions to clinical trials and tissue-specific stem cell transplantation; as well as developing cell manufacturing. He has given numerous tutorials and invited talks in many congresses such as ISSCR (2018). He is the editor of four international books which were published by Springer (2010 and 2012) and John Wiley, USA (2015). He has published 354 international and 102 national peer-reviewed papers, as well as seven chapters in international books, seven books in Persian, and eight translated English text books into Persian.
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An Extracranial Germ-Cell Tumor (EGCT) occurs in the abnormal growth of germ cells in the gonads (testes or ovaries) and the areas other than the brain via tissue, lymphatic system, or circulatory system. The tumor can be benign or malignant (cancerous) by its growth rate. According to the National Cancer Institute and St. Jude Children's Research Hospital, the chance of children who are under 15 years old having EGCTs is 3%, in comparison to adolescents, a possibility of 14% with aged 15 to 19 can have EGCTs. There is no obvious cut point in between children and adolescents.
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Called a Standard Songbook, this collection of 140 old and new songs, beginning with the 16th century and including several Protestant songs, as well as ten of Thurmair's songs, was significant for ecumenical church singing in German and became the germ cell for the Gotteslob of 1975, which incorporated 75 of the Kirchenlied songs. This hymnal was not immediately banned, because of its many Protestant songs. When the Jugendhaus Düsseldorf was closed on 6 February 1939, Thurmair became a freelance writer in Recklinghausen and, a year later, in Munich. He was drafted from 1940 to 1945.
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Loveland received her undergraduate and PhD degrees at Duke University in the United States, studying the molecular basis of mammalian fertilization. She then engaged in postdoctoral studies at Howard Hughes Medical Institute with the University of Texas, before moving to Australia in 1989 to join Monash University. Loveland is a National Health and Medical Research Council of Australia senior research fellow (since 2000) and is a fellow of the Society for the Study of Reproduction. She is a research group head for Testis Development and Male Germ Cell Biology, and head of Postgraduate Studies, School of Clinical Sciences at Monash Health.
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Primordial germ cells are among the first lineages that are established in development and they are the precursors for gametes. It is thought that the process of primordial germ cell migration itself has been conserved rather than the specific mechanisms within it, as chemoattraction and repulsion seem to have been borrowed from blood cells, neurones, and the mesoderm. For most organisms, PGC migration starts in the posterior (back end) of the embryo. This process is in most cases distinct from PGC proliferation, with the exception of mammals in which both processes occur at the same time.
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Ovarian cancer's early stages (I/II) are difficult to diagnose because most symptoms are nonspecific and thus of little use in diagnosis; as a result, it is rarely diagnosed until it spreads and advances to later stages (III/IV). Additionally, symptoms of ovarian cancer may appear similar to irritable bowel syndrome. In patients in whom pregnancy is a possibility, BHCG level can be measured during the diagnosis process. Serum alpha-fetoprotein, neuron- specific enolase, and lactate dehydrogenase can be measured in young girls and adolescents with suspected ovarian tumors as younger patients are more likely to have malignant germ cell tumors.
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The precise structure and function of the four isozymes (Int in E.coli) are solely geared to supply a source of inorganic phosphate when the environment lacks this metabolite. The four enzymes are dependent upon the location of the tissue expression. The four sites of tissue expression are the Intestinal AlP, Placental ALP, Germ Cell ALP and Liver/Bone/Kidney ALP. The inorganic phosphates produced by these isozymes are then bound to carrier proteins which deliver the inorganic phosphates to a specific high-affinity transport system, known as the Pst system, which transports phosphate across the cytoplasmic membrane.
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E. coli cell lysate containing the cellular components required for transcription and translation are used in this in vitro method of protein production. The advantage of such system is that protein may be produced much faster than those produced in vivo since it does not require time to culture the cells, but it is also more expensive. Vectors used for E. coli expression can be used in this system although specifically designed vectors for this system are also available. Eukaryotic cell extracts may also be used in other cell-free systems, for example, the wheat germ cell-free expression systems.
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Prior to their arrival at the gonads, PGCs express pluripotency factors, generate pluripotent cell lines in cell culture (known as EG cells,) and can produce multi-lineage tumors, known as teratomas. Similar findings in other vertebrates indicate that PGCs are not yet irreversibly committed to produce gametes, and no other cell type. On arrival at the gonads, human and mouse PGCs activate widely conserved germ cell-specific factors, and subsequently down-regulate the expression of pluripotency factors. This transition results in the determination of germ cells, a form of cell commitment that is no longer reversible.
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In adult-AMKL, mediastinal germ cell tumors that are associated with adult-AMKL are not seminomas (i.e. do not originate from the sperm cell line) and occur before or concomitantly with but not after the diagnosis AMKL is made. The three most common genetic aberrations in the bone marrow cells of these individuals (representing ~65% of all cases) were inversions in the p arm of chromosome 12, trisomy 8, and an extra X chromosome. In several of these cases, the genetic aberrations in the malignant platelet precursor cells were similar to those in the malignant mediastianal germ cells.
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Human germline engineering is a process in which the human genome is edited within a germ cell, such as a sperm cell or oocyte (causing heritable changes), or in the zygote or embryo following fertilisation. Germline engineering results in changes in the genome being incorporated into every cell in the body of the offspring (or of the individual following embryonic germline engineering). This process differs from somatic cell engineering, which does not result in heritable changes. Most human germline editing is performed on individual cells and non-viable embryos, which are destroyed at a very early stage of development.
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In November 2018, however, a Chinese scientist, He Jiankui, announced that he had created the first human germline genetically edited babies. Genetic engineering relies on a knowledge of human genetic information, made possible by research such as the Human Genome Project, which identified the position and function of all the genes in the human genome. As of 2019, high-throughput sequencing methods allow genome sequencing to be conducted very rapidly, making the technology widely available to researchers. Germline modification is typically accomplished through techniques which incorporate a new gene into the genome of the embryo or germ cell in a specific location.
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The difference may be due to much smaller breast tissue in males and increased estrogen levels in females. The risks of sarcoma, female breast cancer, and haematopoietic malignancies in mutation carriers are more than 100 times greater than those seen in the general population. Other tumours reported in this syndrome, but not yet proved to be linked with it, include melanoma, Wilms' and other kidney tumors, hepatocellular carcinoma, gonadal germ cell, pancreatic, gastric, choroid plexus, colorectal, and prostate cancers. Around 80% of children with adrenocortical carcinoma and 2–10% of childhood brain tumors have p53 mutations.
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The ability to quantitate the βhCG level is useful in the monitoring germ cell and trophoblastic tumors, follow-up care after miscarriage, and diagnosis of and follow-up care after treatment of ectopic pregnancy. The lack of a visible fetus on vaginal ultrasound after the βhCG levels have reached 1500 mIU/ml is strongly indicative of an ectopic pregnancy. Still, even an hCG over 2000 IU/l does not necessarily exclude the presence of a viable intrauterine pregnancy in such cases. As pregnancy tests, quantitative blood tests and the most sensitive urine tests usually detect hCG between 6 and 12 days after ovulation.
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Louis Brian Piccolo (October 31, 1943 – June 16, 1970) was an American professional football player, a running back for the Chicago Bears of the National Football League (NFL) for four years. He died at age 26 from embryonal cell carcinoma, an aggressive form of germ cell testicular cancer, first diagnosed after it had spread to his chest cavity. Piccolo was the subject of the 1971 TV movie Brian's Song, with a remake TV movie of the same name filmed in 2001. He was portrayed in the original film by James Caan and by Sean Maher in the 2001 remake.
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Like Dr. Paolo Sassone-Corsi wrote in this article CREM is “a master-switch regulator in testis”. It plays an important role in the regulation of the expression of post-meiotic genes, and this has been supported by several studies using CREM-mutation mice. The results showed the first step in the process of sperm formation would be blocked if the germ cell development in mice CREM gene were disrupted. The cAMP response element sites can be found in the promoter region of some postmeiotic genes, so that the CREM can target and regulate these genes.
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The various SALL4-null mouse models mimic human mutations in the SALL4 gene, which were shown to cause developmental problems in patients with Okihiro/Duane-Radial-ray syndrome. These individuals frequently have family history of hand malformation and eye movement disorders. SALL4 expression is low to undetectable in most adult tissues with the exception of germ cells and human blood progenitor cells. However, SALL4 is re-activated and mis-regulated in various cancers such as acute myeloid leukemia (AML), B-cell acute lymphocytic leukemia (B-ALL), germ cell tumors, gastric cancer, breast cancer, hepatocellular carcinoma (HCC), lung cancer, and glioma.
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Further elucidating its tumorigenesis function, knocking down SALL4 expression with short hairpin-RNA in leukemic cells or treating these cells with a peptide that mimics the N-12aa of SALL4 to inhibit its interaction with the NuRD complex both result in cell death. These suggest the primary cancer- maintaining property of SALL4 is mediated through its transcriptional repressing function. These observations have led to growing interest in SALL4 as both a diagnostic tool as well as target in cancer therapy. For example, in solid tumors such as germ cell tumors, SALL4 protein expression has become a standard diagnostic biomarker.
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The society, originally founded as the Environmental Mutagen Society (EMS) was formed in the USA in 1969 by Drs. Alexander Hollaender, Joshua Lederberg, James Crow, Ernst Freese, James Neel, William Russell, Heinrich Malling, Frederick J. de Serres, Matthew Meselson, and others. The initial aim was to support the study of environmental mutagenesis, originally in germ-cell mutagenesis, but the scope soon expanded to include all areas of mutagenesis, including mutational mechanisms, test methods, molecular epidemiology, biomarkers, and risk assessment. As a result of this change in scope, in 2012 the society's name was changed to better encompass the broadened reach of the organization.
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Kimo, torn between his beliefs and fame, packs up everything in his house in November and performs one last show with the Protozoa using the old logo and an anti-Principality message. The band is arrested while on stage. Songs in this part: "Germ Cell Tumor", "Two-Headed Monster", and "Escape From Planet Cancer" IV: Eschaton Cycle (Glory of the King) In an Internet chatroom in December, it is revealed that the Protozoa are currently incarcerated by the Principalities. Online, the word "Cancer" has been banned, and users are being forced to use forms such as "c a n c e r" and "ca nc er" to get around it.
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If a substance affects Sertoli and Leydig cell differentiation (a common feature of TDS disorders) at an early developmental stage, germ cell growth and testosterone production will be impaired. These processes are essential for testes descent and genitalia development, meaning that genital abnormalities like cryptorchidism or hypospadias may be present from birth, and fertility problems and TGCC become apparent during adult life. Severity or number of disorders may therefore be dependent on the timing of the environmental exposure. Environmental factors can act directly, or via epigenetic mechanisms, and it is likely that a genetic susceptibility augmented by environmental factors is the primary cause of TDS.
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Krukenberg tumors can be seen in all age groups, with an average age of 45 years. In most countries, cancer that has metastasized to the ovary accounts for only about 1 to 2% of ovarian cancer; in the remainder, the ovary itself is the primary cancer site. However, in Japan they represent a much higher percentage of malignancies in the ovary (almost 20%) due to the increased prevalence of gastric cancer. Krukenberg tumors account for about 15% of metastatic cancers that initially appear to have arisen in the ovary, and as such is less common than metastasis arising from ovarian epithelial and germ-cell tumors.
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TFIIA-alpha and beta-like factor is a protein that in humans is encoded by the GTF2A1L gene. The assembly and stability of the RNA polymerase II transcription pre-initiation complex on a eukaryotic core promoter involve the effects of TFIIA on the interaction between TATA-binding protein (TBP) and DNA. This gene encodes a germ cell-specific counterpart of the large (alpha/beta) subunit of general transcription factor TFIIA that is able to stabilize the binding of TBP to DNA and may be uniquely important to testis biology. Alternative splicing for this locus has been observed and two variants, encoding distinct isoforms, have been identified.
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Undescended testes are associated with reduced fertility, increased risk of testicular germ-cell tumors, and psychological problems when the boy is grown. Undescended testes are also more susceptible to testicular torsion (and subsequent infarction) and inguinal hernias. Without intervention, an undescended testicle will usually descend during the first year of life, but to reduce these risks, undescended testes can be brought into the scrotum in infancy by a surgical procedure called an orchiopexy.The A.D.A.M. Medical Encyclopedia Although cryptorchidism nearly always refers to congenital absence or maldescent, a testis observed in the scrotum in early infancy can occasionally "reascend" (move back up) into the inguinal canal.
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It behaved similarly to a class of genes known as neuroblastoma breakpoint family (NBPF) genes and was thus implicated as a previously unknown member of the neuroblastoma breakpoint family gene. The study was the first germline CNV study in any cancer. Testicular cancer is the most common form of cancer in men between the ages of 15 and 34, but also peaks in infancy and old age. In 2009, in collaboration with the Nathanson Lab at the University of Pennsylvania, the Center published the results of a genome-wide associated study that examined the genomes of 227 patients with testicular germ cell tumors and 919 controls.
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Together with Carol Readhead of the California Institute of Technology, Winston researched male germ cell stem cells and methods for their genetic modification at the Institute of Reproductive and Developmental Biology, Imperial College London. He has published over 300 scientific papers in peer- reviewed journals.Scientific Publications in Peer-review Journals, The Official Site of Professor Robert Winston, accessed on 26 October 2008 He was appointed to a new chair at Imperial College – Professor of Science and Society – and is also emeritus professor of Fertility Studies there. He was Chairman of the Institute of Obstetrics and Gynaecology Trust and chairs the Women-for-Women Appeal.
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The exact function of CTAG1B remains to be unknown. Studies have suggested its role in cell cycle progression and growth, although not being elusive, through the analysis of CTAG1B's structure and expression pattern. The coexpression of CTAG1B with melanoma antigen gene C1 (MAGE-C1), another CTA, further supports its involvement in cell cycle regulation and apoptosis, due to the role of MAGE proteins in these processes. Moreover, its restricted expression pattern in male germ cells suggests its role in germ cell self-renewal or differentiation, supported by the nuclear localization of CTAG1B in mesenchymal stem cells in contrast to its cytoplasmic expression in cancer cells.
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Despite the extensive pre- Franconian history, the foundation of a permanently inhabited settlement in Gonsenheim dates back to Franconian times. The founder was probably a Franconian nobleman named Gunzo, who founded a larger farm in the area of today's Gonsenheim as the germ cell for the later settlement. The establishment of villages with the name ending -heim is typical for settlement foundations in the course of the so-called Frankish colonisation, which took place in the late 5th to 7th centuries. Gonsenheim is one of the villages founded in other Mainz suburbs such as Hechtsheim, Bretzenheim, Ebersheim or Laubenheim, which also date from this period.
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SMAC is involved in cancer, and its overexpression is linked to increased sensitivity in tumor cells to apoptosis. So far, SMAC overexpression has been observed to oppose cancer progression in head and neck squamous cell carcinoma, hepatocellular carcinoma, Hodgkin lymphoma, breast cancer, glioblastoma, thyroid cancer, renal cell carcinoma, testicular germ cell tumors, colorectal cancer, lung cancer, bladder cancer, endometrioid endometrial cancer, and other sarcomas. However, the exact relationship between SMAC and leukemia and hematological diseases remains controversial. SMAC mimetics monotherapy displays improved cytotoxic effects on leukemic cell lines compared to combined therapy with other drugs, which is commonly more effective in other types of cancers.
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In the late 19th century, van Beneden (1883) and Boveri (1890) described meiosis for the first time through a careful observation of germ cell formation in the nematode Ascaris. These observations, together with several further analyses, evidenced that canonical meiosis consists of a first division (called reductional division) that involves the segregation of chromosomal homologs resulting in the reduction of chromosome number and a second division (defined equational division) consisting in the separation of sister chromatids. A general rule for meiosis is therefore: first homologues, then sisters. Schematic comparison of the chromosomal separation occurring during the first meiotic division in standard and inverted meiosis.
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His laboratory also discovered the piwi-interacting RNA (piRNA) pathway and linked this to transposon repression and the protection of germ cell genomes. His innovations include the development of selective re-sequencing strategies, broadly termed exome capture. In 2017, Hannon was awarded a £20 million grant to create a virtual reality interactive map of breast cancer, collaborating with researchers from Switzerland, Ireland, Canada, the USA and the UK. The project allows researchers to study how individual cells within a tumour are arranged and how they interact to allow the tumour to grow. In 2018, it was announced Prof Hannon would guide the Functional Genomics Centre, a collaboration between Cancer Research UK and AstraZeneca.
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Monospecific antibodies are antibodies whose specificity to antigens is singular (mono- + specific) in any of several ways: antibodies that all have affinity for the same antigen; antibodies that are specific to one antigen or one epitope; or antibodies specific to one type of cell or tissue. Monoclonal antibodies are monospecific, but monospecific antibodies may also be produced by other means than producing them from a common germ cell. Regarding antibodies, monospecific and monovalent overlap in meaning; both can indicate specificity to one antigen, one epitope, or one cell type (including one microorganism species). However, antibodies that are monospecific to a certain tissue, or all monospecific to the same tissue because clones, can be polyvalent in their epitope binding.
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Testosterone produced by the testes cannot be directly used due to the mutant androgen receptor that characterizes CAIS; instead, it is aromatized into estrogen, which effectively feminizes the body and accounts for the normal female phenotype observed in CAIS. Immature sperm cells in the testes do not mature past an early stage, as sensitivity to androgens is required in order for spermatogenesis to complete. Germ cell malignancy risk, once thought to be relatively high, is now thought to be approximately 2%. Wolffian structures (the epididymides, vasa deferentia, and seminal vesicles) are typically absent, but will develop at least partially in approximately 30% of cases, depending on which mutation is causing the CAIS.
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Immature, or solid, teratomas are the most common type of ovarian germ cell tumor, making up 40–50% of cases. Teratomas are characterized by the presence of disorganized tissues arising from all three embryonic germ layers: ectoderm, mesoderm, and endoderm; immature teratomas also have undifferentiated stem cells that make them more malignant than mature teratomas (dermoid cysts). The different tissues are visible on gross pathology and often include bone, cartilage, hair, mucus, or sebum, but these tissues are not visible from the outside, which appears to be a solid mass with lobes and cysts. Histologically, they have large amounts of neuroectoderm organized into sheets and tubules along with glia; the amount of neural tissue determines the histologic grade.
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Some surgeons have reported facilitation of surgery, perhaps by enhancing the size, vascularity, or healing of the tissue. A newer hormonal intervention used in Europe is the use of GnRH analogs such as nafarelin or buserelin; the success rates and putative mechanism of action are similar to hCG, but some surgeons have combined the two treatments and reported higher descent rates. Limited evidence suggests that germ cell count is slightly better after hormone treatment; whether this translates into better sperm counts and fertility rates at maturity has not been established. The cost of either type of hormone treatment is less than that of surgery and the chance of complications at appropriate doses is minimal.
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International DeeJay Gigolo Records is a German electronic music record label run by techno artist DJ Hell (real name Helmut Geier). The label was founded in Munich in 1996 as an affiliate of label Disko B. It is Germany's most successful electronic music record label, specialising in electro, house and techno with 80's pop and disco influences. "Gigolo" has released records by Dave Clarke, Jeff Mills, DJ Hell, David Carretta, Miss Kittin & The Hacker, Kiko & Gino S., DJ Naughty, The Penelopes, The Advent, Dopplereffekt, Terrence Fixmer, Japanese Telecom, Fischerspooner, Tiga, Belgian Dj Valium, Princess Superstar and Vitalic. In particular, the label is widely credited as being the germ cell of the electroclash music genre in the late 1990s.
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PARP1 is also over-expressed when its promoter region ETS site is epigenetically hypomethylated, and this contributes to progression to endometrial cancer, BRCA-mutated ovarian cancer, and BRCA-mutated serous ovarian cancer. PARP1 is also over-expressed in a number of other cancers, including neuroblastoma, HPV infected oropharyngeal carcinoma, testicular and other germ cell tumors, Ewing’s sarcoma, malignant lymphoma, breast cancer, and colon cancer. Cancers are very often deficient in expression of one or more DNA repair genes, but over-expression of a DNA repair gene is less usual in cancer. For instance, at least 36 DNA repair enzymes, when mutationally defective in germ line cells, cause increased risk of cancer (hereditary cancer syndromes).
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The Weismann barrier, proposed by August Weismann, is the strict distinction between the "immortal" germ cell lineages producing gametes and "disposable" somatic cells, in contrast to Charles Darwin's proposed pangenesis mechanism for inheritance. In more precise terminology, hereditary information moves only from germline cells to somatic cells (that is, somatic mutations are not inherited). This does not refer to the central dogma of molecular biology, which states that no sequential information can travel from protein to DNA or RNA, but both hypotheses relate to a gene-centric view of life. Weismann set out the concept in his 1892 book Das Keimplasma: eine Theorie der Vererbung (The Germ Plasm: a theory of inheritance).
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This ability has been mapped down to a single gene, sid-2, which, when inserted as a transgene in other species, allows them to take up RNA for RNAi as C. elegans does. Research into meiosis has been considerably simplified since every germ cell nucleus is at the same given position as it moves down the gonad, so is at the same stage in meiosis. In an early phase of meiosis, the oocytes become extremely resistant to radiation and this resistance depends on expression of genes rad51 and atm that have key roles in recombinational repair. Gene mre-11 also plays a crucial role in recombinational repair of DNA damage during meiosis.
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A somatic mutation is change in the DNA sequence of a somatic cell of a multicellular organism with dedicated reproductive cells; that is, any mutation that occurs in a cell other than a gamete, germ cell, or gametocyte. Unlike germline mutations, which can be passed on to the descendants of an organism, somatic mutations are not usually transmitted to descendants. This distinction is blurred in plants, which lack a dedicated germline, and in those animals that can reproduce asexually through mechanisms such as budding, as in members of the cnidarian genus Hydra. While somatic mutations are not passed down to an organism's offspring, somatic mutations will be present in all descendants of a cell within the same organism.
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The nuclear lamina lies on the inner surface of the inner nuclear membrane (INM), where it serves to maintain nuclear stability, organize chromatin and bind nuclear pore complexes (NPCs) and a steadily growing list of nuclear envelope proteins (purple) and transcription factors (pink). Nuclear envelope proteins that are bound to the lamina include nesprin, emerin, lamina-associated proteins 1 and 2 (LAP1 and LAP2), the lamin B receptor (LBR) and MAN1. Transcription factors that bind to the lamina include the retinoblastoma transcriptional regulator (RB), germ cell-less (GCL), sterol response element binding protein (SREBP1), FOS and MOK2. Barrier to autointegration factor (BAF) is a chromatin-associated protein that also binds to the nuclear lamina and several of the aforementioned nuclear envelope proteins.
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CT antigens can be divided by whether they are encoded on the X chromosome (X-CT antigens genes) or not (non-X-CT antigens genes). It has been estimated that 10% of genes on the X chromosome belong to X-CT antigens families. The X-CT antigens genes represent more than half of all CT antigens and often constitute multigene families organized in well-defined clusters long the X chromosome, while the genes of non-X-CT antigens are distributed throughout the genome and are mostly single-copy genes. In normal testis, X-CT antigens genes are expressed primarily on the spermatogonia that are proliferate germ cells, while non-X-CT antigens are expressed in later stages of germ-cell differentiation, such as on spermatocytes.
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It plays a vital role in determining the fates of both inner mass cells and embryonic stem cells and has the ability to maintain pluripotency throughout embryonic development.Wu, Guangming, and Hans R Schöler. “Role of Oct4 in the Early Embryo Development.” Cell Regeneration, vol. 3, no. 1, 2014, doi:10.1186/2045-9769-3-7. Recently, it has been noted that OCT-4 not only maintains pluripotency in embryonic cells but also has the ability to regulate cancer cell proliferation and can be found in various cancers such as pancreatic, lung, liver and testicular germ cell tumors in adult germ cells.Saha, Subbroto Kumar et al. “Systematic expression alteration analysis of master reprogramming factor OCT4 and its three pseudogenes in human cancer and their prognostic outcomes.” Scientific reports vol.
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X-SCID can also arise through de novo mutations and can be prevented in females by X-inactivation. In X-inactivation the preferential selection of the non-mutant X chromosome during development results in the outcome that none of the mature female cells actively express the X-SCID mutation, they are immunologically unaffected and have no carrier burden. A de novo mutation is an alteration in a gene caused by the result of a mutation in a germ cell (egg or sperm) or in the fertilized egg itself, rather than having been inherited from a carrier. Since only 1/3 of all X-SCID patients have a positive family history of SCID, it is hypothesized that de novo mutations account for a significant percentage of cases.
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12...because he poured out > his soul to death and was numbered with the transgressors; yet he bore the > sin of many, and makes intercession for the transgressors. [emphasis added] In ch. 7, "The Mythic-Symbolic Interpretation of the Gospels", Drews writes: Psalm 22:1–8 in St. Albans Psalter – DS DS MS mean Deus, Deus meus, first words in Latin Vulgate > The mythic-symbolic interpretation of the gospels sees in Isaiah 53 the > germ-cell of the story of Jesus, the starting-point of all that is related > of him, the solid nucleus round which all the rest has crystallised. The > prophet deals with the Servant of Jahveh, who voluntarily submits to > suffering in order to expiate the sin and guilt of the people.
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Carboplatin-doublet therapy can be combined with paclitaxel for increased efficacy in some cases. Another potential adjuvant therapy for platinum-sensitive recurrences is olaparib, which may improve progression-free survival but has not been shown to improve overall survival. (Olaparib, a PARP inhibitor, was approved by the US FDA for use in BRCA-associated ovarian cancer that had previously been treated with chemotherapy.) For recurrent germ cell tumors, an additional 4 cycles of BEP chemotherapy is the first-line treatment for those tho have been treated with surgery or platins. If the tumor is determined to be platinum-resistant, vincristine, dactinomycin, and cyclophosphamide (VAC) or some combination of paclitaxel, gemcitabine, and oxaliplatin may be used as a second-line therapy.
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Dysgerminoma accounts for 35% of ovarian cancer in young women and is the most likely germ cell tumor to metastasize to the lymph nodes; nodal metastases occur in 25–30% of cases. These tumors may have mutations in the KIT gene, a mutation known for its role in gastrointestinal stromal tumor. People with an XY karyotype and ovaries (gonadal dysgenesis) or an X,0 karyotype and ovaries (Turner syndrome) who develop a unilateral dysgerminoma are at risk for a gonadoblastoma in the other ovary, and in this case, both ovaries are usually removed when a unilateral dysgerminoma is discovered to avoid the risk of another malignant tumor. Gonadoblastomas in people with Swyer or Turner syndrome become malignant in approximately 40% of cases.
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The miR-92 family is evolutionally conserved microRNAs, and has an ortholog in Caenorhabditis elegans, which has been extensively used as a model organism in the area of developmental biology. mir-235, the miR-92 ortholog in C. elegans, acts in the hypodermis and glial cells to maintain the quiescent state in both neuroblasts and mesoblasts until nutritional state becomes favorable, meaning that mir-235 couples stem cell behaviors to nutritional condition. Furthermore, mir-235 directly represses the expression of nhr-91, which is an ortholog of mammalian germ cell nuclear factor (GCNF), to keep stem cell quiescent. The expression of mir-235 is regulated by the insulin/insulin-like growth factor (IGF) signalling (IIS) pathway in respond to nutritional state.
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Since the germ cell lineage is not established right away by induction, there is a higher chance for mutation to occur before the cells are specified. Mutation rate data is available that indicates a higher rate of germ line mutations in mice and humans, species which undergo induction, than in C. elegans and Drosophila melanogaster, species which undergo inheritance. A lower mutation rate would be selected for, which is one possible reason for the convergent evolution of the germ plasm. However, more mutation rate data will need to be collected across several taxa, particularly data collected both before and after the specification of primordial germ cells before this hypothesis on the evolution of germ plasm can be backed by strong evidence.
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In contrast to bicalutamide and other pure antiandrogens or , antigonadotropic antiandrogens suppress gonadotropin secretion, which in turn diminishes testosterone production by the testes as well as the maintenance of the testes by , resulting in atrophy and loss of their function. As such, bicalutamide and other may uniquely have the potential to preserve testicular function and spermatogenesis and thus male fertility relative to alternative therapies. In accordance with this notion, a study found that prolonged, high-dose bicalutamide treatment had minimal effects on fertility in male rats. However, another study found that low-dose bicalutamide administration resulted in testicular atrophy and reduced the germ cell count in the testes of male rats by almost 50%, though the rate of successful fertilization and pregnancy following mating was not assessed.
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After the selective removal of pluripotent cells, they re-emerge quickly by reverting differentiated cells into stem cells, which leads to tumors. This may be due to the disorder of let-7 regulation of its target Nr6a1 (also known as Germ cell nuclear factor - GCNF), an embryonic transcriptional repressor of pluripotency genes that regulates gene expression in adult fibroblasts following micro-RNA miRNA loss. Teratoma formation by pluripotent stem cells may be caused by low activity of PTEN enzyme, reported to promote the survival of a small population (0.1–5% of total population) of highly tumorigenic, aggressive, teratoma-initiating embryonic-like carcinoma cells during differentiation. The survival of these teratoma-initiating cells is associated with failed repression of Nanog as well as a propensity for increased glucose and cholesterol metabolism.
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In 1969, Dr. Jörg Mittelsten Scheid, Werner’s son, succeeded his uncle as head of the family business. Three years later, Günter Busch and Bernd Balders became the first managing partners who were not members of the founding family. While up to the end of the 1960s the company focused mainly on the production and sale of vacuum cleaners, carpets and upholstery fabrics, ever since that time it has continually diversified, initially into the services sector. Vorwerk was co- founder of the akf bank in 1968; in 1970 the in-house data processing department brought forth the ZEDA Gesellschaft für Datenverarbeitung und EDV- Beratung mbH & Co. KG; and the founding of Hygienic Service Gebäudereinigung und Umweltpflege GmbH in 1974 was the germ cell that led to the Hectas Facility Services division.
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As the BCCI later reduced the number of IPL matches to 74, Sahara demanded for a reduction in the amount of franchise fee to be paid by them to maintain viable IPL proposition. Other reasons included disputes between Sahara and the BCCI regarding the IPL rules, such as player retention and the 4-foreign player rule and also the refusal on the part of the BCCI to allow Pune to add Yuvraj Singh's price to their auction purse so that they could buy another player as a replacement for Yuvraj. Yuvraj was set to miss the whole 2012 season as he was undergoing treatment for germ cell cancer. On 6 February 2012, Subrata Roy, the chairman of Sahara India Pariwar, said that Sourav Ganguly will take a call on reconciliation.
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In 2001, Billy was diagnosed with germ cell seminoma; his was a rare medical situation since this type of cancer usually manifests in men's testicular region, while in Billy's case the tumor appeared in the chest region near his heart. In August 2001, friends organized the Thrash of the Titans benefit concert, held to raise money for Billy's medical expenses. Following chemotherapy, he has since been given a clean bill of health and continued his work with Testament. In March 2020, Billy and his wife Tiffany were tested positive for COVID-19 following the completion of The Bay Strikes Back tour in Europe; he was the third person to have returned home sick from the aforementioned tour, following Will Carroll of Death Angel and Gary Holt of Exodus.
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Whilst retaining its identity as a specific act, Swing on This also refers to the members of the cast. As Falzon describes it: "Rather than putting together a boy band it's about mates coming together and having a sing," Founding members of Swing on This include Michael Falzon, Luke Kennedy, Matt Lee, and Ben Mingay, all seasoned performers in their own right. Rob Mills joined in 2015, as a fifth member, due in part to Lee temporarily returning to Mary Poppins in the UK. The structure of Swing on This is specifically designed for a certain amount of fluidity, allowing the members to continue their individual careers and commitments. On 23 June 2020, producer and founding member Michael Falzon died after a year long battle with germ cell cancer.
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A somatic cell (from Ancient Greek σῶμα sôma, meaning "body"), or vegetal cell, is any biological cell forming the body of an organism; that is, in a multicellular organism, any cell other than a gamete, germ cell, gametocyte or undifferentiated stem cell. In contrast, gametes are cells that fuse during sexual reproduction, germ cells are cells that give rise to gametes, and stem cells are cells that can divide through mitosis and differentiate into diverse specialized cell types. For example, in mammals, somatic cells make up all the internal organs, skin, bones, blood and connective tissue, while mammalian germ cells give rise to spermatozoa and ova which fuse during fertilization to produce a cell called a zygote, which divides and differentiates into the cells of an embryo. There are approximately 220 types of somatic cell in the human body.
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Lisa agrees with Tarasti's assessment, stating that Villa-Lobos rarely develops his musical ideas, but instead merely uses them as stereotyped, repeated formulas, in contrast to composers who relate their different themes, or have evolved them all from a common germ cell. With specific reference to the Third Quartet, she finds the thematic material is "clearly stated and is obviously suitable for development", but that Villa-Lobos fails to provide this development, which is essential to sonata form, instead letting the themes "take their course through the instruments exactly as they were originally conceived" . Paulo , however, contests this view. According to his analysis, both of the main themes of the first movement are taken from the same germ motive, which permeates not only the exposition but the entire first movement of the quartet, "in a process of continuous variation", and compares this high thematic density to the music of Joseph Haydn.
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For several decades, primary lung cancers were consistently dichotomously classified for treatment and research purposes into small-cell lung carcinomas (SCLCs) and non-small- cell lung carcinomas (NSCLCs), based on an oversimplified approach that is now clearly outmoded. The new paradigm recognizes that lung cancers are a large and extremely heterogeneous family of malignant neoplasms, with over 50 different histological variants included in the 4th (2004) revision of the World Health Organization typing system, the most widely used lung cancer classification scheme ("WHO-2004"). These variants are increasingly appreciated as having different genetic, biological, and clinical properties, including prognoses and responses to treatment regimens, and therefore, that correct and consistent histological classification of lung cancers are necessary to validate and implement optimum management strategies. About 1% of lung cancers are sarcomas, germ cell tumors, and hematopoietic tumors, while 99% of lung cancers are carcinoma.
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Clayton-Felt finished the final mixing and production of Spirit Touches Ground in early December 1999, just one week before being hospitalized with what turned out to be choriocarcinoma (a rare form of testicular cancer with the worst prognosis of all germ-cell cancers); he died at the age of 32 less than a month later. Universal relinquished its claim on his unreleased music while Clayton-Felt was hospitalized in a coma, his family whispering the long-sought news into his ear. Led by Laura Baker, Clayton-Felt's sister, a network of friends and fans lobbied for the promotion and distribution of this long- delayed material, eventually organizing for the album completed shortly before his death to be released under the Dreamworks label in 2002. Other unreleased material including the song "Center of Six" itself was released by the Talking Clouds Records label in 2003 on the album Center of Six.
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He worked in different positions, by the end as Vice Director, in the fields of gas adsorption, heterogeneous catalysis and membrane permeation. In 1989 he has got the title Dr. sc. nat. with a thesis on the influence of mass transport in zeolite catalysis. After the closure of the Academy of Sciences by 31 December 1991, Caro founded the research group „Nano-Composites“. This group was the germ cell of the Department of „Functional materials“ in the newly founded Institute of Applied Chemistry (ACA). Under the directorship of Manfred Baerns, Caro was one of the deputy directors at ACA with responsibility for the research field „Reaction engineering and new materials“. In 1992 Caro made his habilitation at Leipzig University on adsorption and catalysis in nanoporous materials and got the title Dr. sc. nat. habil. In 2001 Caro became W3-Professor for Physical Chemistry at Hannover University, the later Leibniz University Hannover.
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Michael I. Kotlikoff is an American researcher, academic leader, and veterinarian, who is currently the Provost of Cornell University.Michael I. Kotlikoff, dean of Vet College, named provost July 16, 2015, Cornell.edu He has been continuously funded by the NIH since 1986, and made significant contributions to muscle biology, heart repair, and mouse genetics. Kotlikoff received his BA degree from the University of Pennsylvania magna cum laude in literature, and his doctorate of veterinary medicine (VMD) summa cum laude from the University of Pennsylvania. He then pursued research training earning a Ph.D. degree in Physiology at the University of California, Davis in 1994, before returning for postdoctoral training at the University of Pennsylvania in the Veterinary and Medical schools. He was a faculty member at Penn, appointed in the Veterinary and Medical Schools from 1985 to 2000, and chaired the Department of Animal Biology at Penn from 1996 to 2000, while also serving as Director of the Center for Animal Transgenesis and Germ Cell Research from 1998-2000.
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In contrast, the germ theory held that the principal cause of cholera was a germ cell that had not yet been identified. Snow theorized that this unknown germ was transmitted from person to person by individuals ingesting water. John Simon, a pathologist and the lead medical officer for London labeled Snow's germ theory as "peculiar". Excerpt from John Simon: > This doctrine is, that cholera propagates itself by a 'morbid matter' which, > passing from one patient in his evacuations, is accidentally swallowed by > other persons as a pollution of food or water; that an increase of the > swallowed germ of the disease takes place in the interior of the stomach and > bowels, giving rise to the essential actions of cholera, as at first a local > derangement; and that 'the morbid matter of cholera having the property of > reproducing its own kind must necessarily have some sort of structure, most > likely that of a cell.
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