Biomedical subjects

C L Songster

Publications and source records attributed to C L Songster.

3 recordsLinked to original sources

PubMed1978

Immunochemical detection of human blood in feces.

Current methods for testing stool samples for hemoglobin utilize peroxidase oxidation of chemical indicators such as guaiac or benzidine. These tests have frequent false-positive and false-negative results, complicating random screening for occult gastrointestinal bleeding. The authors have developed an immunochemical test for human blood in feces using goat antibodies to hemoglobin. When employed in radial immunoassay the test is uncomplicated by cross-reaction with common human foods or other nonhemorrhagic fecal fecal constitutents. The lower limit of sensitivity for hemoglobin in stool samples is 10 mg/dl, compared with a commonly reported threshold of 100 mg/dl for peroxidase tests. The test accurately detects hemoglobin in mixtures of human blood and feces. Immunochemical identification of human blood in stool offers improved detection of lower gastrointestinal bleeding.

Animals↗

PubMed1976

Clinical and morphologic features of hepatic angiosarcoma in vinyl chloride workers.

Fifteen male workers exposed to vinyl chloride developed angiosarcoma of the liver. Thirteen died of disease and two are currently living for short periods after diagnosis. Their ages ranged from 36 to 58 years (average 47.5 years). Their exposure time ranged from 4 to 27.8 years (average 16.9 years). The most common presenting symptoms were fatigue, weight loss, and abdominal pain. Hepatomegaly followed by splenomegaly were the most common physical findings. Biochemical profiles yielded variable results and proved to be of little value in the detection or diagnosis. Of eight patients autopsied, distant organ involvement was present in two cases, duodenal involvement in one, and direct extension of tumor to adjacent organs or tissues in four additional ones. The remainder, diagnosed by open liver biopsy, revealed no tumor extension. The gross features of the tumors were hemorrhagic necrosis, cystic degeneration, fibrosis, and apparent multicentricity. The histologic features were those of the typical angiosarcoma found in a variety of sites with a wide range of cellular differentiation. The histologic diagnosis was often impaired by the extensive tumor necrosis. Elsewhere in the liver subcapsular fibrosis, a distinct type of portal fibrosis, and endothelial cell hyperplasia with or without sinusoidal dilatation were noted. The reduction of industrial chemical exposure has already been achieved and will hopefully eliminate this chemically related tumor in the future. There is, however, a significant group of previously exposed workers who will require careful monitoring to detect functional abnormalities of the liver and possible early neoplastic changes.

Adult↗

PubMed1976

Appearance, properties, and origin of altered human hemoglobin in feces.

Altered hemoglobin (Hb) has been found in the feces as a sequel to an upper gastrointestinal bleed. Active Hb antigen of increased anodic mobility was detected on immunoelectrophoresis of melena stools using a goat anti-Hb. The Hb derivative was also identified in polyacrylamide gel electrophoresis using 412 nm. absorbance. The alteration could be simulated in vitro by incubation of hemolysate with duodenal juice or purified carboxypeptidase B alone, or by a mixture of carboxypeptidases A and B. Treatment of hemolysate or purified Hb with acid, gastric juice, pepsin, pancreatic juice, bile, trypsin, or chymotrypsin failed to produce the characteristic alteration. Instead, no change, or production of alpha and beta chains, or gradual but complete elimination of the Hb antigen was seen. This latter all or none pattern is presumed to prevail in the large bowel on the basis of incubations of hemoglobin-feces mixtures. Individuals documented to be bleeding into the colon were found to have at least a portion of their Hb antigen in the unaltered form by immunoelectrophoresis. This finding may be of value in identifying the general origin of a gastrointestinal bleed.

Carboxypeptidases↗