fatty tissue

tissue /tis·sue/ (tish´u) an aggregation of similarly specialized cells which together perform certain special functions.

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adenoid tissue  lymphoid t.

adipose tissue  connective tissue made of fat cells in meshwork of areolar tissue.

areolar tissue  connective tissue made up largely of interlacing fibers.

bony tissue  bone.

brown adipose tissue  a thermogenic type of adipose tissue containing a dark pigment, and arising during embryonic life in certain specific areas in many mammals, including humans; it is prominent in the newborn.

cancellous tissue  the spongy tissue of bone.

cartilaginous tissue  the substance of cartilage.

chromaffin tissue  a tissue composed largely of chromaffin cells, well supplied with nerves and vessels; it occurs in the adrenal medulla and also forms the paraganglia of the body.

cicatricial tissue  the dense fibrous tissue forming a cicatrix, derived directly from granulation tissue.

connective tissue  the stromatous or nonparenchymatous tissues of the body; that which binds together and is the ground substance of the various parts and organs of the body.

elastic tissue , elastic tissue, yellow connective tissue made up of yellow elastic fibers, frequently massed into sheets.

endothelial tissue  endothelium.

epithelial tissue  epithelium.

erectile tissue  spongy tissue that expands and becomes hard when filled with blood.

extracellular tissue  the total of tissues and body fluids outside the cells.

fatty tissue  adipose t.

fibrous tissue  the common connective tissue of the body, composed of yellow or white parallel fibers.

gelatinous tissue  mucous t.

glandular tissue  an aggregation of epithelial cells that elaborate secretions.

granulation tissue  the newly formed vascular tissue normally produced in healing of wounds of soft tissue, ultimately forming the cicatrix.

gut-associated lymphoid tissue  (GALT) lymphoid tissue associated with the gut, including the tonsils, Peyer's patches, lamina propria of the gastrointestinal tract, and appendix.

indifferent tissue  undifferentiated embryonic tissue.

interstitial tissue  connective tissue between the cellular elements of a structure.

lymphadenoid tissue  tissue resembling that of lymph nodes, found in the spleen, bone marrow, tonsils, and other organs.

lymphoid tissue  a latticework of reticular tissue, the interspaces of which contain lymphocytes.

mesenchymal tissue  mesenchyme.

mucous tissue  a jellylike connective tissue, as occurs in the umbilical cord.

muscle tissue , muscular tissue the substance of muscle, consisting of muscle fibers, muscle cells, connective tissue, and extracellular material.

myeloid tissue  red bone marrow.

nerve tissue , nervous tissue the specialized tissue making up the central and peripheral nervous systems, consisting of neurons with their processes, other specialized or supporting cells, and extracellular material.

osseous tissue  the specialized tissue forming the bones.

reticular tissue , reticulated tissue connective tissue consisting of reticular cells and fibers.

scar tissue  cicatricial t.

sclerous tissues  the cartilaginous, fibrous, and osseous tissue.

skeletal tissue  the bony, ligamentous, fibrous, and cartilaginous tissue forming the skeleton and its attachments.

subcutaneous tissue  the layer of loose connective tissue directly under the skin.

white adipose tissue , yellow adipose tissue the adipose tissue comprising the bulk of the body fat.

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fatty tissue

Etymology: AS, faett + OFr, tissu

loose connective tissue with many cells that contain fat vacuoles. Also called adipose tissue.

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tissue [tish´u]

a group or layer of similarly specialized cells that together perform certain special functions.

adenoid tissue lymphoid tissue.

adipose tissue connective tissue made of fat cells in a meshwork of areolar tissue.

areolar tissue connective tissue made up largely of interlacing fibers.

bony tissue osseous tissue.

brown adipose tissue (brown fat tissue) brown fat.

bursa-equivalent tissue (bursal equivalent tissue) a hypothesized lymphoid tissue in nonavian vertebrates including human beings, equivalent to the bursa of Fabricius in birds: the site of B lymphocyte maturation. It now appears that B lymphocyte maturation occurs primarily in the bone marrow.

cancellous tissue the spongy tissue of bone.

cartilaginous tissue the substance of cartilage.

chordal tissue the tissue of the notochord.

chromaffin tissue a tissue composed largely of chromaffin cells, well supplied with nerves and vessels; it occurs in the adrenal medulla and also forms the paraganglia of the body.

cicatricial tissue the dense fibrous tissue forming a cicatrix, derived directly from granulation tissue; called also scar tissue.

connective tissue the tissue that binds together and is the support of the various structures of the body; see also connective tissue.

elastic tissue connective tissue made up of yellow elastic fibers, frequently massed into sheets.

endothelial tissue peculiar connective tissue lining serous and lymph spaces.

epithelial tissue a general name for tissues not derived from the mesoderm.

erectile tissue spongy tissue that expands and becomes hard when filled with blood.

fatty tissue connective tissue made of fat cells in a meshwork of areolar tissue.

fibrous tissue the common connective tissue of the body, composed of yellow or white parallel elastic and collagen fibers.

gelatinous tissue mucous tissue.

granulation tissue material formed in repair of wounds of soft tissue, consisting of connective tissue cells and ingrowing young vessels; it ultimately forms cicatrix.

gut-associated lymphoid tissue (GALT) lymphoid tissue associated with the gut, including the tonsils, Peyer's patches, lamina propria of the gastrointestinal tract, and appendix.

indifferent tissue undifferentiated embryonic tissue.

interstitial tissue connective tissue between the cellular elements of a structure.

lymphadenoid tissue tissue resembling that of lymph nodes, spleen, bone marrow, tonsils, and lymph vessels.

lymphoid tissue a latticework of reticular tissue whose interspaces contain lymphocytes.

mesenchymal tissue embryonic connective tissue composed of stellate cells and a ground substance of coagulable fluid.

mucous tissue a jellylike connective tissue, such as occurs in the umbilical cord. Called also gelatinous tissue.

muscular tissue the substance of muscle.

myeloid tissue red bone marrow.

nerve tissue (nervous tissue) the specialized tissue forming the elements of the nervous system.

osseous tissue the specialized tissue forming the bones.

reticular tissue (reticulated tissue) connective tissue composed predominantly of reticulum cells and reticular fibers.

scar tissue cicatricial tissue.

sclerous t's the cartilaginous, fibrous, and osseous tissues.

skeletal tissue the bony, ligamentous, fibrous, and cartilaginous tissue forming the skeleton and its attachments.

splenic tissue red pulp.

subcutaneous tissue the layer of loose connective tissue directly under the skin.

tissue typing identification of tissue types for purposes of predicting acceptance or rejection of grafts and transplants. The process and purposes of tissue typing are essentially the same as for blood typing. The major difference lies in the kinds of antigens being evaluated. The acceptance of allografts depends on the hla antigens (HLA); if the donor and recipient are not HLA identical, the allograft is rejected, sometimes within minutes. The HLA genes are located in the major histocompatibility complex, a region on the short arm of chromosome 6, and are involved in cell-cell interaction, immune response, organ transplantation, development of cancer, and susceptibility to disease. There are five genetic loci, designated HLA-A, HLA-B, HLA-C, HLA-D, and HLA-DR. At each locus, there can be any of several different alleles.



Each person inherits one chromosome 6 from the mother and one from the father; that is, each parent transmits to the child one allele for each kind of antigen (A, B, C, D, and DR). If the parents are different at both alleles of a locus, the statistical chance of one sibling being identical to another is one in four (25 per cent), the chance of being identical at one allele only (half-identical) is 50 per cent, and the chance of a total mismatch is 25 per cent.

Techniques for Tissue Typing. Histocompatibility testing involves several basic methods of assay for HLA differences. The most widely used method uses the polymerase chain reaction to compare the DNA of the person, organ, or graft being tested with known pieces of the genes encoding MHC antigens. The variability of these regions of the genes determines the tissue type of the subject.



Serologic methods are used to detect serologically defined antigens on the surfaces of cells. In general, HLA-A, -B, and -C determinants are primarily measured by serologic techniques. A second method, involving lymphocyte reactivity in a mixed lymphocyte culture, for determining HLA-D or lymphocyte-defined antigens, is now only rarely used.

Essentially, the serologic method is performed by incubating target lymphocytes (isolated from fresh peripheral blood) with antisera that recognize all known HLA antigens. The cells are spread in a tray with microscopic wells containing various kinds of antisera and are incubated for 30 minutes, followed by an additional 60-minute complement incubation. If the lymphocytes have on their surfaces antigens recognized by the antibodies in the antiserum, the lymphocytes are lysed. A dye is added to show changes in the permeability of the cell membrane and cellular death. The proportion of cells destroyed by lysis indicates the degree of histologic incompatibility. If, for example, the lymphocytes from a person being tested for HLA-A3 are destroyed in a well containing antisera for HLA-A3, the test is positive for this antigen group.

white adipose tissue (yellow adipose tissue) the adipose tissue composing the bulk of the body fat.

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fatty

pertaining to or characterized by fat. See also adipose.

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fatty acids

organic compounds of carbon, hydrogen and oxygen that are esterified with glycerol to form fat. All fats are esters of fatty acids and glycerol, the fatty acids accounting for 90% of the molecule of most natural fats. A fatty acid consists of a long chain of carbon atoms with a carboxylic acid group at one end. Saturated fatty acids have no double bonds in the carbon chain. The medium and long chain fatty acids are solid at room temperature and are the components of the common animal fats, such as butter and lard. Unsaturated fatty acids contain one or more double bonds. The unsaturated fatty acids are liquid at room temperature and are found in oils such as olive oil and linseed oil. Polyunsaturated fatty acids have two or more double bonds.

Volatile fatty acids (VFAs) including acetic, butyric and propionic acids are produced in large quantities in the rumen by the fermentative digestion of cellulose. Much of the energy consumption of ruminants comes from these VFAs in the situation in which other animals use glucose. See also 3-omega fatty acid (below).

fatty acid nutritional deficiency

a secondary deficiency occurs in pigs on high-calcium diets. This may have a connection with parakeratosis of pigs caused by zinc deficiency and calcium excess in the diet. Requirements for dietary fat in dogs and cats are usually expressed as the essential linoleic acid and arachidonic acid.

fatty acid synthase

in bacteria, a multiprotein complex; in mammals, a single multifunctional protein important in the synthesis of palmitate as a major source of fatty acids.

fatty acyl CoA

generic term for long hydrocarbon chains, generally between C12 and C20, linked via thioester to coenzyme A.

fatty acyl CoA:cholesterol acyltransferase

enzyme (ACAT) catalyzing the transfer of fatty acyl group to cholesterol, irreversible physiologically. Its action regulates the number of LDL receptors by converting excess cholesterol (which inhibits LDL receptors) to cholesterol esters.

branched chain fatty acids

fatty acids usually containing a methyl branch; lowers the melting point compared with the equivalent straight chain fatty acid.

fatty casts

see urinary cast.

fatty degeneration

deposit of fat globules in a tissue.

essential fatty acids (EFA)

essential fatty acids.

fatty liver

accumulation of fat in a liver beyond the level which is normally encountered may be a result of a normal physiological response to increased peripheral lipolysis, obesity or the action of hepatotoxins.

fatty liver disease

see fat cow syndrome.

fatty liver syndrome

1. a disease of laying birds housed in battery cages. The cause is unknown. Affected birds are significantly heavier, there is a fall in egg production and they die acutely of liver rupture. The liver is greasy, mushy in consistency and yellow in color.

2. a severe fatty accumulation in the liver and hypertriglyceridemia that may develop in obese cats that are anorexic. There is jaundice, weight loss, neurological signs and a high mortality. Called also idiopathic feline hepatic lipidosis.

omega-3 (n-3) fatty acids

include α-linolenic acid, eicosapentanoic acid, docosahexanoic acid. High concentrations found in cold water marine (fish) oils.

omega-6 (n-6) fatty acids

found in terrestrial plants, including safflower oil, corn oil and evening primrose oil, which is a rich source of linoleic and arachidonic acids.

fatty tissue

connective tissue made of fat cells in a meshwork of areolar tissue.