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C Brayton

Publications and source records attributed to C Brayton.

5 recordsLinked to original sources

Evaluating mutant mice: anatomic pathology.

As the human and mouse genome projects approach their goals, initiatives in functional genomics are advancing. When the nucleotide sequences are available, identification of gene functions will assume even greater importance. Determination of gene products and their proximal biochemical functions provide a part of the picture, but determination of their functions in the context of the whole organism is the ultimate goal. The manipulated mouse genome has become accepted as a model for understanding the genetic basis of human conditions and diseases. Consequently, biomedical research institutions have seen significant increases in the use of mice since the early 1980s, and these increases are largely attributable to the use of genetically modified mice. The role of comparative pathology in research on mutant mouse models of disease is increasing in response to these trends. Evaluation and phenotypic characterization of mutant mice, via clinical and anatomic pathology techniques, will be an important component of functional genomics initiatives.

Animal Identification Systems↗

Amyloidosis, hemochromatosis, and atherosclerosis in a roseate flamingo (Phoenicopterus ruber).

An aged male roseate flamingo, in a private collection in the British Virgin Islands, was found acutely "down." After four days of supportive therapy, the flamingo succumbed. At necropsy gross lesions included emaciation; collapsed and thickened, yellow abdominal air sac; dark red liver, partially covered by friable yellow material; and a raised, intimal plaque in the aorta near the iliac trifurcation. Histologic examination revealed severe, diffuse, pyogranulomatous air sacculitis with associated locally extensive pleuroperitonitis/perihepatitis. Pansystemic, predominantly periarteriolar distribution of amyloid deposition was evident, as was massive intrahepatocellular accumulation of iron pigment (hemachromatosis/hemosiderosis). A locally extensive, nonobstructive, fibroatheromatous plaque was present in the distal aorta. Amyloidosis, hemochromatosis/hemosiderosis, and atherosclerosis have been recognized in Phoenicopteriformes and other marine or aquatic birds. Their pathogenesis and pathogenicity remain a matter of debate.

Amyloidosis↗

Wasting disease associated with cutaneous and renal nematodes, in commercially obtained Xenopus laevis.

Xenopus laevis, the South African clawed frog or toad, is a member of the family Pipidae. Now in high demand for research purposes, they are available commercially. Its reported lifespan is up to fifteen years. Investigators and caretakers are frustrated when commercially obtained, young frogs (four years or younger), not subjected to any studies, "waste" and die. The wasting syndrome is characterized by anorexia, color change, and "flaky skin." Often the first sign of this syndrome is the presence of large fragments of "flakes" of desquamated epithelium in the water. At necropsy, these frogs are thin and have rough skin instead of smooth slimy skin. Histologic examination reveals tortuous intraepithelial cavities or tunnels that contain nematodes, and associated mild to moderate granulomatous inflammation. Nematodes are also found in the kidneys of some of these frogs, usually in Bowman's space, wrapped around the glomerulus. The cutaneous capillarid nematode is identified as Pseudocapillaroides xenopi. Successful treatment with ivermectin and thiabendizole has been reported. The renal glomerular nematode has not been identified.

Animals↗

Synthesis of type 2 adenovirus DNA in the presence of cycloheximide.

Adenovirus type 2 DNA synthesis, either in permissive human cells or nonpermissive monkey cells, becomes independent of protein synthesis after the appearance of progeny viral DNA. In the presence of cycloheximide, semiconservative replication and initiation of progeny molecules can occur.

Adenoviridae↗