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Apocrine Gland
Apocrine () is a term used to classify the mode of secretion of exocrine glands. In apocrine secretion, secretory cells accumulate material at their apical ends, often forming blebs or "snouts", and this material then buds off from the cells, forming extracellular vesicles. The secretory cells therefore lose part of their cytoplasm in the process of secretion. An example of true apocrine glands is the mammary glands, responsible for secreting breast milk. Apocrine glands are also found in the anogenital region and axillae. Apocrine secretion is less damaging to the gland than holocrine secretion (which destroys a cell) but more damaging than merocrine secretion (exocytosis). File:405 Modes of Secretion by Glands Apocrine.png, Apocrine secretion Image:Apocrine.jpg, Apocrine gland File:Histology of apocrine cells.png, Histology of apocrine cells, H&E stain. Apocrine metaplasia Apocrine metaplasia is a reversible transformation (metaplasia) of cells to an apocrine phenotype. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secretion
Secretion is the movement of material from one point to another, such as a secreted chemical substance from a cell or gland. In contrast, excretion is the removal of certain substances or waste products from a cell or organism. The classical mechanism of cell secretion is via secretory portals at the plasma membrane called porosomes. Porosomes are permanent cup-shaped lipoprotein structures embedded in the cell membrane, where secretory vesicles transiently dock and fuse to release intra-vesicular contents from the cell. Secretion in bacterial species means the transport or translocation of effector molecules. For example: proteins, enzymes or toxins (such as cholera toxin in pathogenic bacteria e.g. '' Vibrio cholerae'') from across the interior (cytoplasm or cytosol) of a bacterial cell to its exterior. Secretion is a very important mechanism in bacterial functioning and operation in their natural surrounding environment for adaptation and survival. In eukaryotic cells ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oncocytes
An oncocyte is an epithelial cell characterized by an excessive number of mitochondria, resulting in an abundant acidophilic, granular cytoplasm. Oncocytes can be benign or malignant. Other names Also known as: *''Hürthle cell'' (thyroid gland only) *'' Oxyphilic cell'' *''Askanazy cell'' *''Apocrine-type metaplasia'' (breast gland only). *''Oncocytic cell'' Etymology Derived from the Greek root onco-, which means mass, bulk. See also * Hurthle cell carcinoma, a variant of follicular thyroid carcinoma. *Oncocytoma, a tumour composed of oncocytes, may be found as a less common salivary gland neoplasm also known as oxyphilic adenoma. *Renal oncocytoma A renal oncocytoma is a tumour of the kidney made up of oncocytes, epithelial cells with an excess amount of mitochondria. Signs and symptoms Renal oncocytomas are often asymptomatic and are frequently discovered by chance on a CT or ultrasoun ..., a kidney tumour composed of oncocytes. References {{Reflist External lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HER2
Receptor tyrosine-protein kinase erbB-2 is a protein that normally resides in the membranes of cells and is encoded by the ''ERBB2'' gene. ERBB is abbreviated from erythroblastic oncogene B, a gene originally isolated from the avian genome. The human protein is also frequently referred to as HER2 (human epidermal growth factor receptor 2) or CD340 (cluster of differentiation 340). HER2 is a member of the human epidermal growth factor receptor (HER/EGFR/ERBB) family. But contrary to other members of the ERBB family, HER2 does not directly bind ligand. HER2 activation results from heterodimerization with another ERBB member or by homodimerization when HER2 concentration are high, for instance in cancer. Amplification or over-expression of this oncogene has been shown to play an important role in the development and progression of certain aggressive types of breast cancer. In recent years the protein has become an important biomarker and target of therapy for approximately 30% of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progesterone Receptor
The progesterone receptor (PR), also known as NR3C3 or nuclear receptor subfamily 3, group C, member 3, is a protein found inside cells. It is activated by the steroid hormone progesterone. In humans, PR is encoded by a single ''PGR'' gene residing on chromosome 11q22, it has two isoforms, PR-A and PR-B, that differ in their molecular weight. The PR-B is the positive regulator of the effects of progesterone, while PR-A serve to antagonize the effects of PR-B. Mechanism Progesterone is necessary to induce activation of the progesterone receptors. When no binding hormone is present the carboxyl terminal inhibits transcription. Binding to a hormone induces a structural change that removes the inhibitory action. Progesterone antagonists prevent the structural reconfiguration. After progesterone binds to the receptor, restructuring with dimerization follows and the complex enters the nucleus and binds to DNA. There transcription takes place, resulting in formation of messenge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estrogen Receptor
Estrogen receptors (ERs) are proteins found in cell (biology), cells that function as receptor (biochemistry), receptors for the hormone estrogen (17β-estradiol). There are two main classes of ERs. The first includes the intracellular estrogen receptors, namely ERα and ERβ, which belong to the nuclear receptor family. The second class consists of membrane estrogen receptors (mERs), such as GPER (GPR30), ER-X, and Gq-mER, Gq-mER, which are primarily G protein-coupled receptors. This article focuses on the nuclear estrogen receptors (ERα and ERβ). Upon activation by estrogen, intracellular ERs undergo protein targeting, translocation to the nucleus where they bind to specific DNA sequences. As DNA-binding transcription factors, they regulate the activity of various genes. However, ERs also exhibit functions that are independent of their DNA-binding capacity. These non-genomic actions contribute to the diverse effects of estrogen signaling in cells. Estrogen receptors (ERs) b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triple-negative Breast Cancer
Triple-negative breast cancer (TNBC) is any breast cancer that either lacks or shows low levels of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) overexpression and/or gene amplification (i.e. the tumor is negative on all three tests giving the name ''triple-negative''). Triple-negative is sometimes used as a surrogate term for basal-like. Triple-negative breast cancer comprises 15–20% of all breast cancer cases and affects more young women or women with a mutation in the BRCA1 gene than other breast cancers. Triple-negative breast cancers comprise a very heterogeneous group of cancers. TNBC is the most challenging breast cancer type to treat. Hormone therapy that is used for other breast cancers does not work for TNBC. In its early stages, the cancer is typically treated through surgery, radiation and chemotherapy. In later stages where surgery is not possible or the cancer has spread from the initial localised area, tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eosinophilic
Eosinophilic (Greek suffix '' -phil'', meaning ''eosin-loving'') describes the staining of tissues, cells, or organelles after they have been washed with eosin, a dye commonly used in histological staining. Eosin is an acidic dye for staining cell cytoplasm, collagen, and muscle fibers. ''Eosinophilic'' describes the appearance of cells and structures seen in histological sections that take up the staining dye eosin. Such eosinophilic structures are, in general, composed of protein. Eosin is usually combined with a stain called hematoxylin to produce a hematoxylin- and eosin-stained section (also called an H&E stain, HE or H+E section). It is the most widely used histological stain for a medical diagnosis. When a pathologist examines a biopsy of a suspected cancer, they will stain the biopsy with H&E. Some structures seen inside cells are described as being eosinophilic; for example, Lewy and Mallory bodies. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcinoma
Carcinoma is a malignancy that develops from epithelial cells. Specifically, a carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that arises from cells originating in the endodermal, mesodermal or ectodermal germ layer during embryogenesis. Carcinomas occur when the DNA of a cell is damaged or altered and the cell begins to grow uncontrollably and becomes malignant. It is from the (itself derived from meaning ''crab''). Classification As of 2004, no simple and comprehensive classification system has been devised and accepted within the scientific community. Traditionally, however, malignancies have generally been classified into various types using a combination of criteria, including: The cell type from which they start; specifically: * Epithelial cells ⇨ carcinoma * Non-hematopoietic mesenchymal cells ⇨ sarcoma * Hematopoietic cells ** Bone marrow–derived cells that normally mature in the bloodstream ⇨ leuke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pure Apocrine Carcinoma Of The Breast
Pure apocrine carcinoma of the breast (PACB) is a rare carcinoma derived from the epithelium, epithelial cells in the lactiferous ducts of the mammary gland. The mammary gland is an apocrine gland. Its lactiferous ducts have two layers of epithelial cells, a luminal layer which faces the duct's Lumen (anatomy), lumen (i.e. passageway) and a basal layer which lies beneath the luminal layer. There are at least four subtypes of epithelial cells in these ducts: luminal progenitor cells and luminal mature cells which reside in the luminal layer and mammary stem cells and basal cells which reside in the basal layer. Examination of the genes expressed in PACB cancer cells indicate that most of these tumors consist of cells derived from luminal cells but a minority of these tumors consist of cells derived from basal cells. Invasive apocrine carcinomas of the breast with an appreciable amount of apocrine gland-like tissue was termed apocrine breast tumors for decades when in 1988 d'Amore et ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histopathology
Histopathology (compound of three Greek words: 'tissue', 'suffering', and '' -logia'' 'study of') is the microscopic examination of tissue in order to study the manifestations of disease. Specifically, in clinical medicine, histopathology refers to the examination of a biopsy or surgical specimen by a pathologist, after the specimen has been processed and histological sections have been placed onto glass slides. In contrast, cytopathology examines free cells or tissue micro-fragments (as "cell blocks "). Collection of tissues Histopathological examination of tissues starts with surgery, biopsy, or autopsy. The tissue is removed from the body or plant, and then, often following expert dissection in the fresh state, placed in a fixative which stabilizes the tissues to prevent decay. The most common fixative is 10% neutral buffered formalin (corresponding to 3.7% w/v formaldehyde in neutral buffered water, such as phosphate buffered saline). Preparation for h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ductal Carcinoma In Situ
Ductal carcinoma ''in situ'' (DCIS), also known as intraductal carcinoma, is a pre-cancerous or non-invasive cancerous lesion of the breast. DCIS is classified as Breast cancer classification#Stage, Stage 0. It rarely produces symptoms or a breast lump that can be felt, typically being detected through screening mammography. It has been diagnosed in a significant percentage of men (see male breast cancer). In DCIS, abnormal cells are found in the lining of one or more milk ducts in the breast. ''In situ'' means "in place" and refers to the fact that the abnormal cells have not moved out of the mammary duct and into any of the surrounding tissues in the breast ("pre-cancerous" indicates that it has not yet become an invasive cancer). In some cases, DCIS may become invasive and spread to other tissues, but there is no way of determining which lesions will remain stable without treatment, and which will go on to become invasive. DCIS encompasses a wide spectrum of diseases rang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acidophilic
Acidophiles or acidophilic organisms are those that thrive under highly acidic conditions (usually at pH 5.0 or below). These organisms can be found in different branches of the tree of life, including Archaea, Bacteria,Becker, A.Types of Bacteria Living in Acidic pH" Retrieved 10 May 2017. and Eukarya. Examples A list of these organisms includes: Archaea :* Sulfolobales, an order in the Thermoproteota branch of Archaea :* Thermoplasmatales, an order in the Euryarchaeota branch of Archaea :* ARMAN, in the Euryarchaeota branch of Archaea :* '' Acidianus brierleyi, A. infernus'', facultatively anaerobic thermoacidophilic archaebacteria :* ''Halarchaeum acidiphilum'', acidophilic member of the Halobacteriacaeae :* ''Metallosphaera sedula'', thermoacidophilic Bacteria :* Acidobacteriota, a phylum of Bacteria :* Acidithiobacillales, an order of Pseudomonadota e.g. ''A. ferrooxidans, A. thiooxidans'' :*''Thiobacillus prosperus, T. acidophilus, T. organovorus, T. cuprinus'' :*'' Ace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
