plaque

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plaque

 [plak]
1. any patch or flat area.
2. a superficial, solid, elevated skin lesion with a diameter equal to or greater than 1.0 cm (0.5 cm according to some authorities); see also papule.
atheromatous plaque fibrous plaque.
dental plaque a dense, nonmineralized, highly organized biofilm of microbes, organic and inorganic material derived from the saliva, gingival crevicular fluid, and bacterial byproducts. It plays an important etiologic role in the development of dental caries and periodontal and gingival diseases; calcified plaque forms dental calculus.
fibrous plaque the lesion of atherosclerosis, a white to yellow area within the wall of an artery that causes the intimal surface to bulge into the lumen; it is composed of lipid, cell debris, smooth muscle cells, collagen, and, in older persons, calcium. Called also atheromatous plaque.
Hollenhorst p's atheromatous emboli containing cholesterol crystals in the retinal arterioles.
pleural p's opaque white plaques on the parietal pleura, visible radiographically in cases of asbestosis.
senile p's microscopic lesions composed of fragmented axon terminals and dendrites surrounding a core of amyloid seen in the cerebral cortex in Alzheimer's disease.

plaque

(plak),
1. A patch or small differentiated area on a body surface (for example, skin, mucosa, or arterial endothelium) or on the cut surface of an organ such as the brain; in skin, a circumscribed, elevated, superficial, and solid area exceeding 1 cm in diameter.
2. An area of clearing in a flat confluent growth of bacteria or tissue cells, such as that caused by the lytic action of bacteriophage in an agar plate culture of bacteria, by the cytopathic effect of certain animal viruses in a sheet of cultured tissue cells, or by antibody (hemolysin) produced by lymphocytes cultured in the presence of erythrocytes and to which complement has been added.
3. A sharply defined zone of demyelination characteristic of multiple sclerosis.
4.
[Fr. a plate]

plaque

(plak)
1. any patch or flat area.
2. a superficial, solid, elevated skin lesion.

attachment plaques  small regions of increased density along the sarcolemma of skeletal muscles to which myofilaments seem to attach.
bacterial plaque , dental plaque a soft thin film of food debris, mucin, and dead epithelial cells on the teeth, providing the medium for bacterial growth. It contains calcium, phosphorus, and other salts, polysaccharides, proteins, carbohydrates, and lipids, and plays a role in the development of caries, dental calculus, and periodontal and gingival diseases.
fibrous plaque  the lesion of atherosclerosis, a pearly white area within an artery that causes the intimal surface to bulge into the lumen; it is composed of lipid, cell debris, smooth muscle cells, collagen, and, in older persons, calcium.
Hollenhorst plaques  atheromatous emboli containing cholesterol crystals in the retinal arterioles, a sign of impending serious cardiovascular disease.
senile plaques  microscopic argyrophilic masses composed of fragmented axon terminals and dendrites surrounding a core of amyloid, seen in small amounts in the cerebral cortex of healthy elderly people and in larger amounts in those with Alzheimer's disease.

plaque

(plăk)
n.
1. A scaly patch on a body part, especially the skin.
2. A biofilm of bacteria in a matrix of polysaccharides and other substances on the surface of a tooth or teeth.
3.
a. A deposit of fatty material on the inner lining of an arterial wall, characteristic of atherosclerosis.
b. The material that such a deposit is composed of.
4. A deposit consisting mainly of beta-amyloid and degenerating nerve tissue, found in the brain tissue of people with Alzheimer's disease.
5. A sharply defined zone of demyelination in the central nervous system characteristic of multiple sclerosis.
6. A clear, often round patch of lysed cells in an otherwise opaque layer of a bacteria or cell culture.

plaque

[plak]
Etymology: Fr, plate
1 a flat, often raised patch on the skin or any other organ of the body.
2 a patch of atherosclerosis.
3 also called bacterial plaque, a usually thin film on the teeth. It is made up of mucin and colloidal material found in saliva and often secondarily invaded by bacteria.

plaque

Cardiology
An early lesion of atherosclerosis which may be found in persons of any age in large vessels.
 
Dentistry
A soft sticky substance on teeth composed of bacteria and saliva; an indurated soft mass of polysaccharides and bacteria—e.g., Lactobacillus acidophilus, Streptococcus mutans.

Dermatology
A flat, solid, elevated, ≥ 1.0-cm-diameter skin nodule formed either by extension or coalescence of papules of lichen amyloidosis, lichen simplex chronicus, lichen planus, or psoriasis; a “plaque” stage occurs in certain skin tumours (e.g., the second stage of Kaposi sarcoma), and evolving mycosis fungoides.
 
Molecular biology
A clear area on a lawn of bacterial cells caused by the lysis of infected cells by a phage.
 
Neuropathology
Shadow plaques—one of multiple, irregularly shaped and sharply demarcated lesions (focal demyelinisation) in the gray and white matter in the brain of patients with multiple sclerosis.

plaque

Cardiology An early lesion of ASHD found in persons of any age in larger vessels Dentistry A soft sticky substance on teeth composed of bacteria and saliva; an indurated gob of polysaccharides and bacteria–eg, Lactobacillus acidophilus, Streptococcus mutans. See Periodontitis Dermatology A flat, solid, elevated ≥ 1. 0 cm in diameter skin nodule formed either by extension or coalescence of papules of lichen amyloidosis, lichen simplex chronicus, lichen planus, psoriasis; a 'plaque' stage occurs in certain skin tumors–eg, the 2nd stages of KS, mycosis fungoides Neurology 'Shadow plaques' Multiple, irregularly shaped, and sharply demarcated lesions–focal demyelinization in the gray and white matter in the brain of Pts with MS. Asymmetric unit membrane plaque, Atherosclerotic plaque, Complicated plaque, Fibrous plaque, Multiple sclerosis, Parietal pleural plaque, Senile plaque, Shadow plaque, Soldier's plaque

plaque

(plak)
1. A patch or small, differentiated area on a body surface (e.g., skin, mucosa, or arterial endothelium) or on the cut surface of an organ such as the brain.
2. An area of clearing in a flat, confluent growth of bacteria or tissue cells.
3. A sharply defined zone of demyelination characteristic of multiple sclerosis.
[Fr. a plate]

plaque

1. An area of ATHEROMA found in the inner lining of arteries in the disease of ATHEROSCLEROSIS.
2. A sticky mixture of food debris, saliva and bacteria that persists around the necks of uncleaned teeth and is the main cause of tooth decay.

plaque

  1. a clear area in a ‘lawn’ of bacterial growth, in which the bacteria have undergone LYSIS due to BACTERIOPHAGE infection. The number of plaque-forming units in a given volume applied to the lawn can be used to calculate viral numbers in a suspension.
  2. a layer that forms on the surface of a tooth, composed of bacteria in an organic matrix (see BIOFILM). As the layer thickens, anaerobic respiration of the bacteria produces acids which dissolve the tooth enamel.

Plaque

Patches of scar tissue that form where the layer of yelin covering the nerve fibers is destroyed by the multiple sclerosis disease process.

plaque

zone of demyelination along nerve fibre, characteristic of multiple sclerosis or other demyelinating diseases

plaque

, placque (plak)
2. Patch or small, differentiated area on body surface (e.g., skin, mucosa, or arterial endothelium) or on cut surface of an organ.
3. An area of clearing in a flat, confluent growth of bacteria or tissue cells.
[Fr. a plate]

plaque (dental) (plak),

n 1. in dentistry, a biofilm noted in the oral cavity. It consists of salivary proteins, microorganisms, and other byproducts of the microorganism. A type of intercellular matrix is also present. It forms on the oral cavity surface after the formation of the salivary pellicle using selective attachment factors. It is a factor in initiation and continuation of dental caries and periodontal disease. Older terms:
mucin plaque, bacterial plaque. 2. deposits of cholesterol in the arteries, possibly causing disease.
plaque, cocci in
n.pl the gram-positive microorganisms occurring in early-developing plaque that are later replaced with filaments as the plaque matures.
plaque, epithelium-associated,
n the loosely attached subgingival plaque found in the epithelium of the periodontal pocket that consists of gram-negative microorganisms and white blood cells.
plaque, fissure,
n a plaque that develops in the pit and fissures of a tooth.
plaque, pigmented dental,
n a colored plaque that is not related to the development of gingivitis and is often found in oral cavities that are almost plaque free. The plaque may be colonized by pigment-producing bacteria. The condition may be controlled by diligent plaque removal, but reoccurrence is possible. Also called
black line stain.
plaque, subgingival,
n a thick, noncalcified mass of plaque situated inferior to the gingival margin. It may or may not be attached to the epithelium or tooth and may cover subgingival calculus. It cannot be removed with flow of saliva or water. It can calcify with minerals from the lamina propria's blood vessels and become subgingival calculus.
plaque, supragingival
n a thick, noncalcified mass of plaque superior to the gingival margin. It cannot be removed with flow of saliva or water. It may or may not cover supragingival calculus. It may appear on any surface in the oral cavity. It can calcify from salivary minerals and become supragingival calculus. It can be stained with disclosing solutions. See also disclosing solution.
Enlarge picture
Supragingival plaque.
plaque, tooth-surface-attached,
n a type of subgingival plaque that uses selective attachment factors and is located in the subgingival area. This type of plaque is implicated in the formation of caries of the root and eventual breakdown of the root (resorption).

plaque

1. any patch or flat area.
2. a clear area of cell lysis caused by viral replication on a cell monolayer.

amniotic plaque
small, 1 to 2 inch diameter, poxlike lesion on the inside of the amnion. Constant on the bovine amnion during the middle trimester and causes no problems.
annular plaque
seen in equine lupus erythematosus panniculitis.
plaque assay
a method of quantifying the number of infectious units by inoculating serial dilutions of a viral suspension on a cell culture monolayer, overlaying with a medium containing agarose and after several days incubation, counting the number of plaques formed; recorded as plaque forming units/ml.
atheromatous plaque
a deposit of predominantly fatty material in the lining of blood vessels occurring in atherosclerosis.
bacterial plaque, dental plaque
a mass adhering to the enamel surface of a tooth, composed of a mixed colony of bacteria in an intercellular matrix of bacterial and salivary polymers and remnants of epithelial cells and leukocytes. It may cause caries, dental calculi and periodontal disease.
cutaneous plaque
an elevated, solid structure without a necrotic center, up to 1 to 2 inch diameter with an unbroken surface.
drug plaque
cutaneous, subcutaneous or subconjunctival deposits formed as a result of injection of some drugs, particularly repository steroid preparations. May be unsightly and a cause of conjunctivitis.
ear plaque
see ear plaque.
eosinophilic plaque
see eosinophilic plaque.
plaque-forming cells
see plaque assay (above).
plaque-forming count
the number of plaques formed in the plaque assay.
senile plaque
described in the brain of old dogs.
siderotic plaque
nodules observed as dry, yellow encrustations on the splenic capsule of old dogs.
References in periodicals archive ?
Les plaquettes de hachich, saisies en possession des deux mis en cause, sont frappees du logo de la 2eme chaEne.
Ma l'autocensura feroce, la repressione che regna sovrana, la noia che si estende al di la di ogni immaginazione fanno si che spentisi gli ultimi applausi si torni a casa sapendo di non aver ascoltato, di non aver capito, la fantasia indurita come un sesso che non scorge alcun sollievo, con un gran buco nella testa dove le parole sono finite come in un incineritore, magari perfino contenti di avere fatto un minimo di pubbliche relazioni, di avere rimediato una labile alleanza, di avere scroccato una cena col direttore di una collana, di avere strappato una nuova lettura, di avere saputo di una nuova rivista che forse prendera in visione i nostri versi, la promessa di una plaquette, un articolo, una recensione, una frase, un rigo appena.
Les dechets de cuivre saisis par la brigade du poste de surveillance de Honaine ont ete decouverts a Fellaoucene dissimules sous forme de plaquettes concassees au milieu du gravat de construction, a bord d'un camion.
Poussant un peu plus leurs investigations, les enqueteurs vont remonter le circuit de ce trafic en mettant le grappin, sur indications des deux dealers, sur leur fournisseur chez qui les policiers vont saisir treize plaquettes de cette drogue soit 1,3 kilogramme, selon la meme source, indiquant que deux autres revendeurs qu'approvisionnait ce dernier sont activement recherches.
Twelve of the ladies were in the queen's service and two in the service of Madame de Bourbon; among those of the queen was Mademoiselle de Chateaubriant, Monsieur de Lautrec's sister, dressed in a gown of dark crimson velvet embroidered all over with gold chains bearing silver plaquettes well placed within the chains, on which were inscribed devices.
RELIGIOUS Italian Renaissance plaquettes worth around pounds 500, 000 have been stolen from the Victoria & Albert Museum.
Since then many volumes and plaquettes have poured forth from his provocative pen: Liberes (1970), just taken up again with A la Vieille Parque (1989) in the 1993 Collection Poesie edition; Aux chiens du soir (1979), Laures (1984), et cetera.
Il est compose de globules rouges, de globules blancs et de plaquettes qui baignent dans un liquide appele plasma.
Selon lui, [beaucoup moins que] une pochette de sang sert a trois malades (plasma, plaquettes et globules rouges) [beaucoup plus grand que].
The numerous engraved plaquettes of Gonnersdorf and La Marche are mentioned briefly in the catalogue, with no illustrations, but the exhibition would have greatly benefited by featuring just one of the detailed faces among the many human depictions from La Marche.
Fashion, Devotion and Contemplation: The Status and Functions of Italian Renaissance Plaquettes
Philip Attwood's discriminating examination of Giovanni Bernardi, an artist better known for his engraved compositions in rock crystal (and to a lesser extent, the bronze plaquettes derived from those glyptic works), supplements documentary evidence with the careful analytical tools of a connoisseur.