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Vasculogenesis
Vasculogenesis is the process of blood vessel formation, occurring by a ''De novo synthesis, de novo'' production of endothelial cells. It is the first stage of the formation of the vascular network, closely followed by angiogenesis. Process In the word sense, sense distinguished from angiogenesis, vasculogenesis is different in one aspect: whereas angiogenesis is the formation of new blood vessels from pre-existing ones, vasculogenesis is the formation of new blood vessels, in blood islands, when there are no pre-existing ones. For example, if a monolayer of endothelial cells begins sprouting to form capillary, capillaries, angiogenesis is occurring. Vasculogenesis, in contrast, is when endothelial precursor cells (angioblasts) migrate and differentiate in response to local cues (such as growth factors and extracellular matrices) to form new blood vessels. These vascular trees are then pruned and extended through angiogenesis. Occurrences Vasculogenesis occurs during embryon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Vascular Remodelling In The Embryo
Vascular remodelling is a process which occurs when an immature heart begins contracting, pushing fluid through the early vasculature. The process typically begins at day 22, and continues to the tenth week of human embryogenesis. This first passage of fluid initiates a signal cascade and cell movement based on physical Sensory cue, cues including shear stress and circumferential stress, which is necessary for the remodelling of the vascular network, artery, arterial-vein, venous identity, angiogenesis, and the regulation of genes through mechanotransduction. This embryonic process is necessary for the future stability of the mature vascular network. Vasculogenesis is the initial establishment of the components of the blood vessel network, or vascular tree. This is dictated by genetic factors and has no inherent function other than to lay down the preliminary outline of the circulatory system. Once fluid flow begins, biomechanics, biomechanical and hemodynamic inputs are applied to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
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] [Amazon] |
Neovascularization
Neovascularization is the natural formation of new blood vessels ('' neo-'' + ''vascular'' + '' -ization''), usually in the form of functional microvascular networks, capable of perfusion by red blood cells, that form to serve as collateral circulation in response to local poor perfusion or ischemia. Growth factors that inhibit neovascularization include those that affect endothelial cell division and differentiation. These growth factors often act in a paracrine or autocrine fashion; they include fibroblast growth factor, placental growth factor, insulin-like growth factor, hepatocyte growth factor, and platelet-derived endothelial growth factor. There are three different pathways that comprise neovascularization: (1) vasculogenesis, (2) angiogenesis, and (3) arteriogenesis. Three pathways of neovascularization Vasculogenesis Vasculogenesis is the de novo formation of blood vessels. This primarily occurs in the developing embryo with the development of the first primitive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Endothelial Progenitor Cell
Endothelial progenitor cell (or EPC) is a term that has been applied to multiple different cell types that play roles in the regeneration of the endothelial lining of blood vessels. Outgrowth endothelial cells are an EPC subtype committed to endothelial cell formation. Despite the history and controversy, the EPC in all its forms remains a promising target of regenerative medicine research. History and controversy Developmentally, the endothelium arises in close contact with the hematopoietic system. This, and the existence of hemogenic endothelium, led to a belief and search for adult hemangioblast- or angioblast-like cells; cells which could give rise to functional vasculature in adults. The existence of endothelial progenitor cells has been posited since the mid-twentieth century, however their existence was not confirmed until the 1990s when Asahara et al. published the discovery of the first putative EPC. Recently, controversy has developed over the definition of true en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
HP59
HP59 is a pathologic angiogenesis capillary endothelial marker protein (7 or 12 transmembrane domains) which has been identified as the receptor for the Group B Streptococcal Toxin (GBS Toxin) molecule known as CM101, the etiologic agent for early-onset versus late-onset Group B Strep. Expression Fu, ''et al.'' coined the term "pathological angiogenesis" to distinguish between HP59-expressing, and non-HP59-expressing capillaries, however, other researchers have not used this terminology. Therefore it is not yet known whether HP59 is expressed in vasculogenesis, arteriogenesis, sprouting angiogenesis or intussusceptive angiogenesis. However capillaries in all tumor tissues examined were positive for anti-HP59 antibodies and Von Willebrand factor (vWF) antibodies, while in normal tissues only vWF staining was observed. The target protein for GBStoxin/CM101 is expressed in vasculature of developing organs during their formation during embryogenesis. The lung is the last organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Endometriosis
Endometriosis is a disease in which Tissue (biology), tissue similar to the endometrium, the lining of the uterus, grows in other places in the body, outside the uterus. It occurs in women and a limited number of other female mammals. Endometrial tissue most often grows on or around reproductive organs such as the ovaries and fallopian tubes, on the outside surface of the uterus, or the tissues surrounding the uterus and the ovaries (peritoneum). It can also grow on other organs in the pelvic region like the Gastrointestinal tract, bowels, stomach, bladder, or the cervix. Rarely, it can also occur in other parts of the body. Symptoms can be very different from person to person, varying in range and intensity. About 25% of individuals have no symptoms, while for some it can be a debilitating disease. Common symptoms include pelvic pain, Heavy menstrual bleeding, heavy and Dysmenorrhea, painful periods, pain with bowel movements, Dysuria, painful urination, Dyspareunia, pain dur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Capillary
A capillary is a small blood vessel, from 5 to 10 micrometres in diameter, and is part of the microcirculation system. Capillaries are microvessels and the smallest blood vessels in the body. They are composed of only the tunica intima (the innermost layer of an artery or vein), consisting of a thin wall of simple squamous endothelial cells. They are the site of the exchange of many substances from the surrounding interstitial fluid, and they convey blood from the smallest branches of the arteries (arterioles) to those of the veins (venules). Other substances which cross capillaries include water, oxygen, carbon dioxide, urea, glucose, uric acid, lactic acid and creatinine. Lymph capillaries connect with larger lymph vessels to drain lymphatic fluid collected in microcirculation. Etymology ''Capillary'' comes from the Latin word , meaning "of or resembling hair", with use in English beginning in the mid-17th century. The meaning stems from the tiny, hairlike diameter of a capi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Angioblast
Angioblasts (or vasoformative cells) are embryonic cells from which the endothelium of blood vessels arises. They are derived from embryonic mesoderm. Blood vessels first make their appearance in several scattered vascular areas ( blood islands) that are developed simultaneously between the endoderm and the mesoderm of the yolk-sac, i. e., outside the body of the embryo. Here a new type of cell, the angioblast, is differentiated from the mesoderm. These cells as they divide form small, dense syncytial masses, which soon join with similar masses by means of fine processes to form plexuses. They form capillaries through vasculogenesis and angiogenesis. Angioblasts are one of the two products formed from hemangioblasts (the other being multipotential hemopoietic stem cells). See also *List of human cell types derived from the germ layers This is a list of Cell (biology), cells in humans derived from the three embryonic germ layers – ectoderm, mesoderm, and endoderm. Cells d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Development Of The Circulatory System
In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek meaning ''heart'', and Latin meaning ''vessels''). The circulatory system has two divisions, a systemic circulation or circuit, and a pulmonary circulation or circuit. Some sources use the terms ''cardiovascular system'' and ''vascular system'' interchangeably with ''circulatory system''. The network of blood vessels are the great vessels of the heart including large elastic arteries, and large veins; other arteries, smaller arterioles, capillaries that join with venules (small veins), and other veins. The circulatory system is closed in vertebrates, which means that the blood never leaves the network of blood vessels. Many invertebrates such as arthropods have an open circulatory system with a heart that p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Vasculogenic Mimicry
Vasculogenic mimicry (VM) is a strategy used by tumors to ensure sufficient blood supply is brought to its cells through establishing new tumor vascularization. This process is similar to tumor angiogenesis; on the other hand vascular mimicry is unique in that this process occurs independent of endothelial cells. Vasculature is instead developed ''De novo mutation, de novo'' by cancer cells, which under stress conditions such as Hypoxia (medical), hypoxia, express similar properties to stem cells, capable of differentiating to mimic the function of endothelial cells and form vasculature-like structures. The ability of tumors to develop and harness nearby vasculature is considered one of the hallmarks of cancer disease development and is thought to be closely linked to tumor invasion and metastasis. Vascular mimicry has been observed predominantly in aggressive and metastatic cancers and has been associated with negative tumor characteristics such as increased metastasis, increased ti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Ocular Ischemic Syndrome
Ocular ischemic syndrome is the constellation of ocular signs and symptoms secondary to severe, chronic arterial hypoperfusion to the eye. Amaurosis fugax is a form of acute vision loss caused by reduced blood flow to the eye; it may be a warning sign of an impending stroke, as both stroke and retinal artery occlusion can be caused by thromboembolism due to atherosclerosis elsewhere in the body (such as coronary artery disease and especially carotid atherosclerosis). Retinal artery occlusion is also caused by a left atrial thrombus in patients with atrial fibrillation. Consequently, those with transient blurring of vision are advised to urgently seek medical attention for a thorough evaluation of the carotid artery. Anterior segment ischemic syndrome is a similar ischemic condition of anterior segment usually seen in post-surgical cases. Retinal artery occlusion (such as central retinal artery occlusion or branch retinal artery occlusion) leads to rapid death of retinal cells, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
