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Angiocentric glioma

Angiocentric glioma is a rare WHO grade 1 pediatric-type diffuse low-grade glioma of cortex or brainstem causing refractory seizures, defined by MYB::QKI fusion and cured by resection.

Angiodysplasia of colon

Angiodysplasia of the colon (colonic angioectasia, vascular ectasia): degenerative right-colon vascular malformation causing lower GI bleeding and anemia, mainly over age 60; diagnosed by colonoscopy, treated with argon plasma coagulation.

Angiodysplasia of stomach

Angiodysplasia of stomach (ICD-11 DA43.1, 胃の血管拡張症) is a mucosal vascular malformation of the stomach causing GI bleeding and anemia, treated mainly by argon plasma coagulation and linked to aortic stenosis in Heyde syndrome.

Angioedema

Angioedema is transient non-pitting swelling of skin or mucosa, mediated by histamine or bradykinin. Key forms are hereditary angioedema (C1-INH deficiency, 1:50,000), acquired C1-INH deficiency, and ACE inhibitor-induced angioedema; mediator determines treatment.

Angiogenesis

Angiogenesis is new blood-vessel formation by sprouting or splitting of existing vessels, driven by hypoxia-HIF-VEGF signaling; it underlies development, exercise adaptation, tumors, and wet AMD, and is targeted by anti-VEGF drugs such as bevacizumab and ranibizumab.

Angiogenin

Angiogenin, also called ribonuclease 5, is a 123-amino-acid human protein that stimulates new blood vessel formation; isolated in 1985, its mutations are linked to ALS progression.

Angiography

Angiography, also called angiogram or catheter angiography, is x-ray imaging of blood vessels after contrast dye injection. Key facts: first angiogram 1896 (Haschek and Lindenthal), Seldinger technique 1953, iodine contrast, CTA and MRA alternatives.

Angioimmunoblastic T-cell lymphoma

Angioimmunoblastic T-cell lymphoma (AITL), or nodal T-follicular helper cell lymphoma, angioimmunoblastic type, is an aggressive T-cell non-Hodgkin lymphoma of TFH-cell origin with TET2, RHOA G17V, IDH2, and DNMT3A mutations, immune dysregulation, and poor prognosis.

Angiokeratoma

Angiokeratoma, including Fordyce, Mibelli, circumscriptum, and corporis diffusum types, is a benign dilated capillary lesion of the superficial dermis; the diffuse form marks Fabry disease.

Angiokeratoma circumscriptum

Angiokeratoma circumscriptum (AKC, angiokeratoma circumscriptum neviforme) is the rarest angiokeratoma variant, a congenital capillary-lymphatic malformation of the papillary dermis forming dark hyperkeratotic plaques, usually unilaterally on the lower limbs, first described by Fabry in 1915.

Angiokeratoma of Mibelli

Angiokeratoma of Mibelli (Mibelli's angiokeratoma) is a rare benign vascular skin disease: multiple 3–5 mm warty dark-red papules on fingers and toes, appearing in girls aged 10–15, treated with pulsed dye laser.

Angiology

Angiology is a monthly peer-reviewed medical journal of vascular diseases founded in 1950, published by SAGE, official organ of the American College of Angiology and International College of Angiology, indexed in MEDLINE since 1965.

Angioma serpiginosum

Angioma serpiginosum, also called Hutchinson angioma serpiginosum, is a rare benign vascular nevus of dilated papillary dermal capillaries, affecting females about 9:1, diagnosed by dermoscopic red lagoons, treated with pulsed dye laser.

Angiomatoid fibrous histiocytoma

Angiomatoid fibrous histiocytoma is a rare soft tissue tumor of intermediate biologic potential, arising as a slow-growing, painless nodule on the extremities of children and young adults.

Angiomyolipoma

Angiomyolipoma (AML) is a benign renal PEComa tumour of fat, smooth muscle, and dysmorphic vessels; 0.44% prevalence, 80% sporadic, managed by surveillance, embolization, or nephron-sparing surgery.

Angioplasty

Angioplasty, also called balloon angioplasty, PTCA, or PCI, is a catheter procedure that inflates a balloon to widen plaque-narrowed arteries, usually with a stent. First performed by Andreas Grüntzig in Zürich in 1977; used for angina and heart attacks.

Angioplasty, Balloon, Laser-Assisted

Laser-assisted balloon angioplasty (MeSH D017222, laser balloon angioplasty, PTLA) combines laser energy with balloon catheters to recanalize arteries; randomized trials found no benefit over balloon angioplasty alone, and only excimer lasers remain in use.

Angiosarcoma

Angiosarcoma is a rare malignant tumor of blood and lymph vessel endothelial cells, about 1-2% of sarcomas, most common over age 70, often skin, breast, liver, or spleen; risk factors include lymphedema (Stewart-Treves syndrome) and prior radiation.

Angiosarcoma of breast

Angiosarcoma of the breast (ICD-11 2B56.2) is a rare endothelial malignancy occurring as primary disease in women 30-50 or as secondary radiation-associated disease about 5-10 years after breast radiotherapy, with poor prognosis.

Angiosarcoma of heart

Primary cardiac angiosarcoma (PCAS) is a rare, aggressive malignant tumor of the heart's blood vessel endothelium, mostly in the right atrium, with median survival about 7 months and treatment centered on surgery plus chemo-radiotherapy.

Angiosarcoma of liver

Angiosarcoma of the liver (hepatic angiosarcoma, PHA): rare malignant vascular tumor, about 2% of primary liver cancers, linked to vinyl chloride, Thorotrast, arsenic; median survival 2 months, resection best option.

Angiosarcoma of skin

Cutaneous angiosarcoma is a rare, aggressive vascular sarcoma of the skin, mainly of the elderly head and scalp, or secondary to radiation or lymphedema; 5-year survival is roughly 30% and treatment is surgery plus radiotherapy.

Angioscopes

Angioscopes are fiber-optic endoscopic catheters (angioscopy) that take true-color video images inside blood vessels. Oldest coronary optical imaging tool; FDA-approved but mainly research use; requires balloon occlusion and saline flushing.

Angioscopy

Angioscopy, or coronary angioscopy, is an endoscopic imaging technique in which a fiber-optic catheter camera directly views blood vessel surfaces, chiefly coronary arteries, for plaque and thrombus.

Angiosperm terpene synthase clades (TPS-a, TPS-b, TPS-c, TPS-g)

The angiosperm terpene synthase clades TPS-a, TPS-b, TPS-c, and TPS-g are subfamilies of plant terpene synthase enzymes; TPS-a, b, and g occur only in flowering plants.

Angiostrongyliasis

Angiostrongyliasis, or rat lungworm disease, is caused by the nematodes Angiostrongylus cantonensis (eosinophilic meningitis) and A. costaricensis (abdominal form), acquired by eating raw snails, slugs, or paratenic hosts; over 7,000 cases recorded worldwide.

Angiostrongylus cantonensis

Angiostrongylus cantonensis, the rat lungworm, is a metastrongyloid nematode causing eosinophilic meningitis in humans, acquired from snails or slugs; described by Chen in 1935 in Guangzhou, now spread to about 30 countries.

Angiostrongylus vasorum

Angiostrongylus vasorum, the French heartworm, is a metastrongyloid nematode of dog and fox pulmonary arteries and right heart, transmitted by snails and slugs, causing pneumonia and coagulopathy in dogs and spreading across Europe.

Angiotensin

Angiotensin, especially angiotensin II, is the effector peptide of the renin-angiotensin system regulating blood pressure; discovered 1898-1958, targeted by ACE inhibitors and ARBs, whose comparative cardiovascular outcomes differ across trial populations.

Angiotensin II

Angiotensin II is an octapeptide hormone of the renin-angiotensin-aldosterone system that raises blood pressure by constricting blood vessels, and its synthetic form is an intravenous drug, Giapreza, for septic shock.