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Biomedical subjects

L Kramer

Publications and source records attributed to L Kramer.

At least 109 records · Page 6Linked to original sources

MR imaging of diplomyelia.

We present an unusual case of duplication of the fifth lumbar vertebra and sacrum in a 6-year-old boy. The spinal cord was also duplicated and tethered by bone spurs bilaterally. The imaging features and the embryological basis of diplomyelia are discussed.

Abnormalities, Multiple↗

Gastric spiral bacilli in captive cheetahs.

Two kinds of gastric spiral bacilli were identified in the stomachs of captive cheetahs with naturally occurring gastritis. One type was morphologically similar to 'Gastrospirillum hominis'. This organism could not be cultured in vitro. Some of these bacteria had superficial helical filaments, and others did not. The other type was morphologically, biochemically, and bacteriologically similar to Helicobacter pylori. This organism is most likely a new species of Helicobacter. One or both of these bacteria may have been responsible for the gastritis seen in these cheetahs.

Acinonyx↗

Coccidiosis as a cause of transmural lymphocytic enteritis and mortality in captive Nashville warblers (Vermivora ruficapilla).

Transmural lymphocytic enteritis was diagnosed in thirteen Nashville warblers (Vermivora ruficapilla) during an epornitic with high mortality. In the intestinal lesions, asexual stages of coccidia were present within lymphocytes and asexual and sexual stages of coccidia were present within intestinal villar epithelium. Ultrastructurally, the infiltrating lymphocytes resembled granular ("intraepithelial") lymphocytes, a cell known to be important in the life cycle of some avian coccidia. Gross and histopathologic features of this enteritis resemble intestinal changes described for Isospora/Atoxoplasma spp. in other passeriformes and lymphoproliferative disease in gold-finches.

Animals↗

Felbamate.

Explore the source record for details and available documents.

Administration, Oral↗

Gamma-glutamylcysteine synthetase deficiency and hemolytic anemia.

gamma-Glutamylcysteine synthetase is one of the enzymes of glutathione (GSH) synthesis. A deficiency of this enzyme has been found only once previously in humans: it was associated with spinocerebellar degeneration and hemolytic anemia. We report the case of a woman, daughter of fifth cousins, who was gamma-glutamylcysteine-synthetase-deficient. Modest decreases in the amount of GSH in cultured lymphoblasts and fibroblasts could be documented. The amount of residual enzyme was insufficient to permit detailed studies of the characteristics of the mutant enzymes, but no major abnormality in its Km for cysteine and glutamic acid or in its heat stability were found. In contrast to the earlier report, the only manifestation of the enzyme deficiency was hemolytic anemia. This leads us to conclude that either the occurrence of neurologic symptoms in the other reported family was a chance association or that the clinical expression of this rare defect is pleomorphic.

Adult↗

Do protein and phosphorus cause calcium loss?

The widespread opinion that both protein and phosphorus cause calcium loss is examined. Controlled human studies show that commonly used complex dietary proteins, which have a high phosphorus content, do not cause calcium loss in adult humans. Similarly, a phosphorus intake of up to 2000 mg/d does not have adverse effects on calcium metabolism; however, the type of phosphate contained in carbonated beverages may not behave in the same manner. In contrast, a diet low in protein and phosphorus may have adverse effects on calcium balance in the elderly. Studies with adults suggest that high protein foods do not cause calcium loss.

Animals↗

Effect of zinc supplements on the intestinal absorption of calcium.

Pharmacologic doses of zinc are widely used as zinc supplements. As calcium and zinc may compete for common absorption sites, a study was carried out on the effect of a pharmacologic dose of zinc on the intestinal absorption of calcium in adult males. The analyzed dietary zinc intake in the control studies was normal, averaging 14.6 mg/day. During the high zinc study, 140 mg zinc as the sulfate was added daily for time periods ranging from 17 to 71 days. The studies were carried out during both a low calcium intake averaging 230 mg/day and during a normal calcium intake of 800 mg/day. Calcium absorption studies were carried out during the normal and high zinc intake by using an oral tracer dose of Ca47 and determining plasma levels and urinary and fecal excretions of Ca47. The study has shown that, during zinc supplementation, the intestinal absorption of calcium was significantly lower during a low calcium intake than in the control study, 39.3% vs 61% respectively, p less than 0.001. However, during a normal calcium intake of 800 mg/day, the high zinc intake had no significant effect on the intestinal absorption of calcium. These studies have shown that the high zinc intake decreased the intestinal absorption of calcium during a low calcium intake but not during a normal calcium intake.

Adult↗

Osteoporosis, calcium requirement, and factors causing calcium loss.

A large percentage of subjects receiving a normal calcium intake of 800 mg per day was in negative calcium balance and increasing the calcium intake to various levels up to 2200 mg per day showed a plateau of the calcium balance at the 1200 mg per day intake, indicating a threshold of calcium absorption at this intake level. Dietary factors, such as a phosphorus intake up to 2000 mg per day and complex proteins, such as red meat, do not cause calcium loss. Several commonly used drugs induce significant calcium loss, particularly aluminum-containing antacids, and, if used for prolonged periods of time, can contribute to the development of osteoporosis.

Adult↗