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β-hCG
Choriogonadotropin subunit beta (CG-beta) also known as chorionic gonadotrophin chain beta is a protein that in humans is encoded by the ''CGB'' gene. This gene is a member of the glycoprotein hormone beta chain family and encodes the beta 3 subunit of human chorionic gonadotropin, chorionic gonadotropin (CG). Glycoprotein hormones are heterodimers consisting of a common chorionic gonadotropin alpha, alpha subunit and a unique beta subunit which confers biological specificity. CG is produced by the trophoblastic cells of the placenta and stimulates the ovaries to synthesize the steroids that are essential for the maintenance of pregnancy. The beta subunit of CG is encoded by 6 genes which are arranged in tandem and inverted pairs on chromosome 19q13.3 and contiguous with the luteinizing hormone beta subunit gene. Structure CGB is composed of 165 Amino acid, amino acids, and has a molecular weight of 17.739 Dalton (unit), kDa. On this polypeptide, there are 7 total sites of gly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Chorionic Gonadotropin
Human chorionic gonadotropin (hCG) is a hormone for the maternal recognition of pregnancy produced by trophoblast cells that are surrounding a growing embryo (syncytiotrophoblast initially), which eventually forms the placenta after implantation. The presence of hCG is detected in some pregnancy tests (HCG pregnancy strip tests). Some cancerous tumors produce this hormone; therefore, elevated levels measured when the patient is not pregnant may lead to a cancer diagnosis and, if high enough, paraneoplastic syndromes, however, it is unknown whether this production is a contributing cause or an effect of carcinogenesis. The pituitary analog of hCG, known as luteinizing hormone (LH), is produced in the pituitary gland of males and females of all ages. Beta-hCG is initially secreted by the syncytiotrophoblast. Structure Human chorionic gonadotropin is a glycoprotein composed of 237 amino acids with a molecular mass of 36.7 kDa, approximately 14.5kDa αhCG and 22.2kDa βhCG ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miscarriage
Miscarriage, also known in medical terms as a spontaneous abortion, is an end to pregnancy resulting in the loss and expulsion of an embryo or fetus from the womb before it can fetal viability, survive independently. Miscarriage before 6 weeks of gestation is defined as biochemical loss by European Society of Human Reproduction and Embryology, ESHRE. Once ultrasound or histological evidence shows that a pregnancy has existed, the term used is clinical miscarriage, which can be "early" (before 12 weeks) or "late" (between 12 and 21 weeks). Spontaneous fetal termination after 20 weeks of gestation is known as a stillbirth. The term ''miscarriage'' is sometimes used to refer to all forms of pregnancy loss and pregnancy with abortive outcomes before 20 weeks of gestation. The most common symptom of a miscarriage is vaginal bleeding, with or without pain. Tissue (biology), Tissue and clot-like material may leave the uterus and pass through and out of the vagina. Risk factors for misc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syncytiotrophoblast
The syncytiotrophoblast (from the Greek 'syn'- "together"; 'cytio'- "of cells"; 'tropho'- "nutrition"; 'blast'- "bud") is the epithelial covering of the highly vascular embryonic placental villi, which invades the wall of the uterus to establish nutrient circulation between the embryo and the mother. It is a multinucleate, terminally differentiated syncytium, extending to 13cm. Function It is the outer layer of the trophoblasts and actively invades the uterine wall, during implantation, rupturing maternal capillaries and thus establishing an interface between maternal blood and embryonic extracellular fluid, facilitating passive exchange of material between the mother and the embryo. The syncytial property is important since the mother's immune system includes white blood cells that are able to migrate into tissues by "squeezing" in between cells. If they were to reach the fetal side of the placenta, many foreign proteins would be recognized, triggering an immune reaction. H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytotrophoblast
"Cytotrophoblast" is the name given to both the inner layer of the trophoblast (also called layer of Langhans) or the cells that live there. It is interior to the syncytiotrophoblast and external to the wall of the blastocyst in a developing embryo. The cytotrophoblast is considered to be the trophoblastic stem cell because the layer surrounding the blastocyst remains while daughter cells differentiate and proliferate to function in multiple roles. There are two lineages that cytotrophoblastic cells may differentiate through: fusion and invasive. The fusion lineage yields syncytiotrophoblast and the invasive lineage yields interstitial cytotrophoblast cells. Cytotrophoblastic cells play an important role in the implantation of an embryo in the uterus. Fusion lineage The formation of all syncytiotrophoblast is from the fusion of two or more cytotrophoblasts via this fusion pathway. This pathway is important because the syncytiotrophoblast plays an important role in fetal-materna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corpus Luteum
The corpus luteum (Latin for "yellow body"; : corpora lutea) is a temporary endocrine structure in female ovaries involved in the production of relatively high levels of progesterone, and moderate levels of estradiol, and inhibin A. It is the remains of the ovarian follicle that has released a mature ovum during a previous ovulation. The corpus luteum is colored as a result of concentrating carotenoids (including lutein) from the diet and secretes a moderate amount of estrogen that inhibits further release of gonadotropin-releasing hormone (GnRH) and thus secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). A new corpus luteum develops with each menstrual cycle. Development and structure The corpus luteum develops from an ovarian follicle during the luteal phase of the menstrual cycle or oestrous cycle, following the release of a secondary oocyte from the follicle during ovulation. The follicle first forms a corpus hemorrhagicum before it beco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progesterone
Progesterone (; P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the major progestogen in the body. Progesterone has a variety of important functions in the body. It is also a crucial metabolic intermediate in the production of other endogenous steroids, including the sex hormones and the corticosteroids, and plays an important role in brain function as a neurosteroid. In addition to its role as a natural hormone, progesterone is also used as a medication, such as in combination with estrogen for contraception, to reduce the risk of Uterine cancer, uterine or cervical cancer, in hormone replacement therapy, and in feminizing hormone therapy. It was first prescribed in 1934. Biological activity Progesterone is the most important progestogen in the body. As a potent agonist of the progesterone receptor, nu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angiogenesis
Angiogenesis is the physiological process through which new blood vessels form from pre-existing vessels, formed in the earlier stage of vasculogenesis. Angiogenesis continues the growth of the vasculature mainly by processes of sprouting and splitting, but processes such as coalescent angiogenesis, vessel elongation and vessel cooption also play a role. Vasculogenesis is the embryonic formation of endothelial cells from mesoderm cell precursors, and from neovascularization, although discussions are not always precise (especially in older texts). The first vessels in the developing embryo form through vasculogenesis, after which angiogenesis is responsible for most, if not all, blood vessel growth during development and in disease. Angiogenesis is a normal and vital process in growth and development, as well as in wound healing and in the formation of granulation tissue. However, it is also a fundamental step in the transition of tumors from a benign state to a malign ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immune Tolerance In Pregnancy
Immune tolerance in pregnancy or maternal immune tolerance is the immune tolerance shown towards the fetus and placenta during pregnancy. This tolerance counters the immune response that would normally result in the rejection of something foreign in the body, as can happen in cases of spontaneous abortion. It is studied within the field of reproductive immunology. Mechanisms Placental mechanisms The placenta functions as an immunological barrier between the mother and the fetus, creating an immunologically privileged site. For this purpose, it uses several mechanisms: *It secretes neurokinin B containing phosphocholine molecules. This is the same mechanism used by parasitic nematodes to avoid detection by the immune system of their host. *Also, there is the presence of small lymphocytic suppressor cells in the fetus that inhibit maternal cytotoxic T cells by inhibiting the response to interleukin 2. * The placental trophoblast cells do not express the classical MHC class I i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endometrium
The endometrium is the inner epithelium, epithelial layer, along with its mucous membrane, of the mammalian uterus. It has a basal layer and a functional layer: the basal layer contains stem cells which regenerate the functional layer. The functional layer thickens and then is shed during menstruation in humans and some other mammals, including other apes, Old World monkeys, some species of bat, the elephant shrew and the Cairo spiny mouse. In most other mammals, the endometrium is reabsorbed in the estrous cycle. During pregnancy, the glands and blood vessels in the endometrium further increase in size and number. Vascular spaces fuse and become interconnected, forming the placenta, which supplies oxygen and nutrition to the embryo and fetus.Blue Histology - Female Reproductive System ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blastocyst
The blastocyst is a structure formed in the early embryonic development of mammals. It possesses an inner cell mass (ICM) also known as the ''embryoblast'' which subsequently forms the embryo, and an outer layer of trophoblast cells called the trophectoderm. This layer surrounds the inner cell mass and a fluid-filled cavity or lumen known as the blastocoel. In the late blastocyst, the trophectoderm is known as the trophoblast. The trophoblast gives rise to the chorion and amnion, the two fetal membranes that surround the embryo. The placenta derives from the embryonic chorion (the portion of the chorion that develops villi) and the underlying uterine tissue of the mother. The corresponding structure in non-mammalian animals is an undifferentiated ball of cells called the blastula. In humans, blastocyst formation begins about five days after fertilization when a fluid-filled cavity opens up in the morula, the early embryonic stage of a ball of 16 cells. The blastocyst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
