An insoluble protein substance that causes disease (amyloidosis) when deposited in large quantities in tissues.
An adjective meaning "starch-like." Also used as a noun to refer to a protein-polysaccharide complex that forms deposits in organs and vessels.
a complex protein substance that builds up in tissues in amyloidosis.
Any one of various complex proteins that are deposited in tissues in different disease processes. These proteins have an affinity for Congo red dye. In neuropsychiatry, of particular interest are the beta-amyloid (A4) protein, which is the major component of the characteristic senile plaques of Alzheimer's disease, and the amyloid precursor protein (APP).
for fungal structures, a positive reaction (bluish to black) when treated with iodine such as in Melzer's reagent or Lugol's solution
a chemical staining reaction in which the tissue, spore wall ornamentation, etc. stains bluish-black in Melzer's reagent. Examples include the spore ornamentation of species in the genera Russula and Lactarius.
a nonnitrogenous food substance consisting chiefly of starch; any substance resembling starch
(pathology) a waxy translucent complex protein resembling starch that results from degeneration of tissue
a misshapen or misfolded protein that can be produced by various parts of the body and which may deposit in other parts of the body (nerves or organs)
a term used to describe the protein fragments that are produced by the body naturally
A group of abnormal proteins that cause disorders of the brain, heart, kidney, and other organs. Alzheimer's disease is characterized by deposits of a certain form of the beta sub-type of amyloid within the brain. close window Aphasia Impaired or absent comprehension or production of, or communication by, speech, writing, or signs, due to an acquired lesion of the dominant cerebral hemisphere. close window
Deposition of a protein called amyloid, derived from amylin, in cells of the pancreas, causing dysfunction of these cells. This acts like scar tissue and produces a diffusion barrier, which results in a secretory and an absorptive defect to insulin.
"Starch-like." In myeloma, amyloid develops when pieces of immunoglobulin(referred to as light chains) deposit in tissues. Organ failure can occur as a result.
plaques - unusual clumps of material found in the tissue between nerve cells. Amyloid plaques, which consist of a protein called beta amyloid along with degenerating bits of neurons and other cells, are a hallmark of Alzheimer's disease.
A protein that is found in the brains of people with Alzheimer's disease. It is deposited throughout the brain in microscopic clumps known as plaques. Its function is unknown and it may be the cause of the deterioration of brain function.
A proteinaceous fibrillar material deposited in various tissues and organs, sometimes secondary to a chronic inflammatory disease.
Any of a number of complex proteins that are deposited in tissues and that share selected laboratory features such as a change in the fluorescence intensity of certain aromatic dyes like Congo Red. See the entire definition of Amyloid
An abnormal substance deposited between and within cells. Amyloid stains with the Congo Red stain. In Alzheimer's disease amyloid is abnormally deposited in neuritic plaques and in small blood vessels.
A protein-polysaccharide complex having starchlike characteristics produced and deposited in tissues during certain pathological states.
spores and hyphae are designated as amyloid if they turn grey or blue-black upon treatment with Melzer's Iodine reagent (see dextrinoid, IKI-).
Of spore walls, spore ornamentation, hyphal walls, ascus tips, etc.: Staining blue or grayish to blackish-violet in Melzer's reagent, presumably because of the presence of starch or a starch-like compound. ( 17)
A chemical struture which can accumulate in brain tissue as a result of a variety of different diseases. In CJD the amyloid is normally made-up of the prion protein.
A chemical structure which can accumulate in brain or other tissues in an amorphous way as a result of a variety of different diseases. In CJD the amyloid is made-up of the prion protein.
a type of aging pigment which accumulates in the nerve cells and is believed to damage nervous tissues by compression and infiltration, and by blocking proper flow of vital nutrients. One type of amyloid is comprised of antibody-antigen complexes and is caused by an autoimmune disease.
A chemical that builds up inside tissue in an amorphous way.
A waxy translucent substance composed mostly of protein, that forms plaques (abnormal deposits) in the brain.
blue black when stained with Meltzers iodine
A protein deposit associated with tissue degeneration; amyloid is found in the brains of individuals with Alzheimer’s.
A waxy translucent substance consisting of protein in combination with polysaccharides that is deposited in some animal organs and tissues under abnormal conditions (as Alzheimer's disease).
Amyloids are insoluble fibrous protein aggregations sharing specific structural traits. The name amyloid comes from the early mistaken identification of the substance as starch (amylum in Latin), based on crude iodine-staining techniques. For a period, the scientific community debated whether or not amyloid deposits were fatty deposits or carbohydrate deposits until it was finally resolved that it was neither, but rather a deposition of proteinaceous mass (Reviewed by Kyle, 2001).