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Vascular Endothelial Growth Factor A
Vascular endothelial growth factor A (VEGF-A) is a protein that in humans is encoded by the ''VEGFA'' gene. Function This gene is a member of the platelet-derived growth factor (PDGF)/vascular endothelial growth factor (VEGF) family and encodes a protein that is often found as a disulfide linked homodimer. This protein is a glycosylated mitogen that specifically acts on endothelial cells and has various effects, including mediating increased vascular permeability, inducing angiogenesis, vasculogenesis and endothelial cell growth, promoting cell migration, and inhibiting apoptosis. Alternatively spliced transcript variants, encoding either freely secreted or cell-associated isoforms, have been characterized. VEGF-A shows prominent activity with vascular endothelial cells, primarily through its interactions with the VEGFR1 and -R2 receptors found in prominently on the endothelial cell membrane. Although, it does have effects on a number of other cell types (e.g., stimulation mon ... [...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 residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 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 peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesenchyme
Mesenchyme () is a type of loosely organized animal embryonic connective tissue of undifferentiated cells that give rise to most tissues, such as skin, blood or bone. The interactions between mesenchyme and epithelium help to form nearly every organ in the developing embryo. Vertebrates Structure Mesenchyme is characterized morphologically by a prominent ground substance matrix containing a loose aggregate of reticular fibers and unspecialized mesenchymal stem cells. Mesenchymal cells can migrate easily (in contrast to epithelial cells, which lack mobility), are organized into closely adherent sheets, and are polarized in an apical-basal orientation. Development The mesenchyme originates from the mesoderm. From the mesoderm, the mesenchyme appears as an embryologically primitive "soup". This "soup" exists as a combination of the mesenchymal cells plus serous fluid plus the many different tissue proteins. Serous fluid is typically stocked with the many serous elements, su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
POEMS Syndrome
POEMS syndrome (also termed osteosclerotic myeloma, Crow–Fukase syndrome, Takatsuki disease, or PEP syndrome) is a rare paraneoplastic syndrome caused by a clone of aberrant plasma cells. The name POEMS is an acronym for some of the disease's major signs and symptoms ( polyneuropathy, organomegaly, endocrinopathy, myeloma protein, and skin changes), as is PEP ( polyneuropathy, endocrinopathy, plasma cell dyscrasia). The signs and symptoms of most neoplasms are due to their mass effects caused by the invasion and destruction of tissues by the neoplasms' cells. Signs and symptoms of a cancer causing a paraneoplastic syndrome result from the release of humoral factors such as hormones, cytokines, or immunoglobulins by the syndrome's neoplastic cells and/or the response of the immune system to the neoplasm. Many of the signs and symptoms in POEMS syndrome are due at least in part to the release of an aberrant immunoglobulin, i.e. a myeloma protein, as well as certain cyto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitric Oxide
Nitric oxide (nitrogen oxide or nitrogen monoxide) is a colorless gas with the formula . It is one of the principal oxides of nitrogen. Nitric oxide is a free radical: it has an unpaired electron, which is sometimes denoted by a dot in its chemical formula (•N=O or •NO). Nitric oxide is also a heteronuclear diatomic molecule, a class of molecules whose study spawned early modern theories of chemical bonding. An important intermediate in industrial chemistry, nitric oxide forms in combustion systems and can be generated by lightning in thunderstorms. In mammals, including humans, nitric oxide is a signaling molecule in many physiological and pathological processes. It was proclaimed the "Molecule of the Year" in 1992. The 1998 Nobel Prize in Physiology or Medicine was awarded for discovering nitric oxide's role as a cardiovascular signalling molecule. Nitric oxide should not be confused with nitrogen dioxide (NO2), a brown gas and major air pollutant, or with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vasodilation
Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. The process is the opposite of vasoconstriction, which is the narrowing of blood vessels. When blood vessels dilate, the flow of blood is increased due to a decrease in vascular resistance and increase in cardiac output. Therefore, dilation of arterial blood vessels (mainly the arterioles) decreases blood pressure. The response may be intrinsic (due to local processes in the surrounding tissue) or extrinsic (due to hormones or the nervous system). In addition, the response may be localized to a specific organ (depending on the metabolic needs of a particular tissue, as during strenuous exercise), or it may be systemic (seen throughout the entire systemic circulation). Endogenous substances and drugs that cause vasodilation are termed vasodilators. Such vasoactivity is necessar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granulocytes
Granulocytes are cells in the innate immune system characterized by the presence of specific granules in their cytoplasm. Such granules distinguish them from the various agranulocytes. All myeloblastic granulocytes are polymorphonuclear. They have varying shapes (morphology) of the nucleus (segmented, irregular; often lobed into three segments); and are referred to as polymorphonuclear leukocytes (PMN, PML, or PMNL). In common terms, ''polymorphonuclear granulocyte'' refers specifically to "neutrophil granulocytes", the most abundant of the granulocytes; the other types (eosinophils, basophils, and mast cells) have varying morphology. Granulocytes are produced via granulopoiesis in the bone marrow. Types There are four types of granulocytes (full name polymorphonuclear granulocytes): * Basophils * Eosinophils * Neutrophils * Mast cells Except for the mast cells, their names are derived from their staining characteristics; for example, the most abundant granulocyte is the neu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrophages
Macrophages (abbreviated as M φ, MΦ or MP) ( el, large eaters, from Greek ''μακρός'' (') = large, ''φαγεῖν'' (') = to eat) are a type of white blood cell of the immune system that engulfs and digests pathogens, such as cancer cells, microbes, cellular debris, and foreign substances, which do not have proteins that are specific to healthy body cells on their surface. The process is called phagocytosis, which acts to defend the host against infection and injury. These large phagocytes are found in essentially all tissues, where they patrol for potential pathogens by amoeboid movement. They take various forms (with various names) throughout the body (e.g., histiocytes, Kupffer cells, alveolar macrophages, microglia, and others), but all are part of the mononuclear phagocyte system. Besides phagocytosis, they play a critical role in nonspecific defense (innate immunity) and also help initiate specific defense mechanisms (adaptive immunity) by recruiting other immune ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemotactic
Chemotaxis (from '' chemo-'' + '' taxis'') is the movement of an organism or entity in response to a chemical stimulus. Somatic cells, bacteria, and other single-cell or multicellular organisms direct their movements according to certain chemicals in their environment. This is important for bacteria to find food (e.g., glucose) by swimming toward the highest concentration of food molecules, or to flee from poisons (e.g., phenol). In multicellular organisms, chemotaxis is critical to early development (e.g., movement of sperm towards the egg during fertilization) and development (e.g., migration of neurons or lymphocytes) as well as in normal function and health (e.g., migration of leukocytes during injury or infection). In addition, it has been recognized that mechanisms that allow chemotaxis in animals can be subverted during cancer metastasis. The aberrant chemotaxis of leukocytes and lymphocytes also contribute to inflammatory diseases such as atherosclerosis, asthma, and arthr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vessel Fenestrations
A fenestra (fenestration; plural fenestrae or fenestrations) is any small opening or pore, commonly used as a term in the biological sciences. It is the Latin word for "window", and is used in various fields to describe a pore in an anatomical structure. Biological morphology In morphology, fenestrae are found in cancellous bones, particularly in the skull. In anatomy, the round window and oval window are also known as the ''fenestra rotunda'' and the ''fenestra ovalis''. In microanatomy, fenestrae are found in endothelium of fenestrated capillaries, enabling the rapid exchange of molecules between the blood and surrounding tissue. The elastic layer of the tunica intima is a fenestrated membrane. In surgery, a fenestration is a new opening made in a part of the body to enable drainage or access. Plant biology and mycology In plant biology, the perforations in a perforate leaf are also described as fenestrae, and the leaf is called a fenestrate leaf. The leaf window is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lumen (anatomy)
In biology, a lumen (plural lumina) is the inside space of a tubular structure, such as an artery or intestine. It comes . It can refer to: *The interior of a vessel, such as the central space in an artery, vein or capillary through which blood flows. *The interior of the gastrointestinal tract *The pathways of the bronchi in the lungs *The interior of renal tubules and urinary collecting ducts *The pathways of the female genital tract, starting with a single pathway of the vagina, splitting up in two lumina in the uterus, both of which continue through the Fallopian tubes In cell biology, a lumen is a membrane-defined space that is found inside several organelles, cellular components, or structures: * thylakoid, endoplasmic reticulum, Golgi apparatus, lysosome, mitochondrion, or microtubule Transluminal procedures ''Transluminal procedures'' are procedures occurring through lumina, including: * Natural orifice transluminal endoscopic surgery in the lumina of, for exa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matrix Metalloproteinase
Matrix metalloproteinases (MMPs), also known as matrix metallopeptidases or matrixins, are metalloproteinases that are calcium-dependent zinc-containing endopeptidases; other family members are adamalysins, serralysins, and astacins. The MMPs belong to a larger family of proteases known as the metzincin superfamily. Collectively, these enzymes are capable of degrading all kinds of extracellular matrix proteins, but also can process a number of bioactive molecules. They are known to be involved in the cleavage of cell surface receptors, the release of apoptotic ligands (such as the FAS ligand), and chemokine/cytokine inactivation. MMPs are also thought to play a major role in cell behaviors such as cell proliferation, migration (adhesion/dispersion), differentiation, angiogenesis, apoptosis, and host defense. They were first described in vertebrates (1962), including humans, but have since been found in invertebrates and plants. They are distinguished from other endopeptidase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
