Search PubMed⌕ Search

Biomedical subjects

J J Cerda

Publications and source records attributed to J J Cerda.

At least 73 records · Page 4Linked to original sources

Glutathione peroxidase acitvity in intestinal and liver tissues of rats fed various levels of selenium, sulfur and alpha-tocopherol.

The effects of various levels of selenium, alpha-tocopherol and sulfur on glutathione peroxidase (GSH-Px) activity in intestinal and liver tissues were determined in male rats fed corn-soybean or Torula yeast diets. Rats fed corn-soybean diets had greater GSH-Px activity in the small intestine, colon and liver tissues, catalase activity and selenium in the liver, and body weight gains than those fed Torula yeast diets. GSH-Px activity in the small intestine, colon, and liver tissues as well as concentration of selenium in the liver increased with increasing levels of selenium in Torula yeast diets but not with corn-soybean diets. Tocopherol supplementation had no significant effect on GSH-Px activity in rats fed Torula yeast or corn-soybean diets supplemented with selenium. Supplemental sulfur decreased GSH-Px activity in the small intestine tissues and increased activity in colon tissues.

Animal Feed↗

Effect of diphenylhydantoin on the bioavailability of citrus folate.

Long term use of the drug diphenylhydantoin (DPH) has been associated with biochemical evidence of folic acid deficiency and rarely with megaloblastic anemia. The mechanism of this nutritional deficiency is uncertain but is thought to result from DPH-induced alteration in the intestinal absorption of conjugated and/or free dietary folate. The effect of DPH on the intestinal absorption of free folates from a food source has heretofore not been reported. In this study triple lumen tube perfusion of the human jejunum was used to quantitate folate absorption from a control solution of orange juice and from an identical solution containing DPH. The results in eleven volunteers serving as their own controls indicate no effectof DPH at a concentration of 20 microgram/ml on folate absorption from this food source. The predominant form of folate in orange juice as determined by differential microbiologic assay is N-5-methyltetrahydrofolate. DPH does not appear to interfere with the absorption of free food folate which is both methylated and reduced.

Adult↗

Effect of physical activity on human potassium metabolism in a hot and humid environment.

Previous investigations have suggested that there are high potassium losses during heavy physical activities in hot climates. In order to determine if high levels of potassium losses could be offset by potassium loading, this study was conducted with five long-distance track runners who had trained in hot and humid environments. The liquid supplements containing 4.3, 98.0, and 0.0 mEq/liter of potassium were given 1 to 2 hr before physical activity. The daily diet contained 2.6 g of potassium. A sodium and potassium balance study was conducted in which stool, urine, and dermal losses were measured. In order to determine if there was a change in the distribution of body potassium during physical exercise, seven subjects total body potassium was estimated before and after exercise. This measurement was performed by counting 40K in a whole body counter. Although the subjects with potassium supplementation and higher urinary sodium and potassium losses, the 98 mEq/liter of potassium supplement resulted in a positive potassium balance. The subjects' potassium requirements exceeded the National Research Council suggested dietary intake. The total body potassium measurements indicated that the counting efficiency of 40K increases significantly immediately after the period of vigorous exercise.

Adult↗

Calcified mucinous adenocarcinoma of the stomach.

Two cases of unusual mucinous adenocarcinomas of the stomach with calcification are reported. One of the cases demonstrated hypercalcemia. Endoscopic verification of the calcifications was confirmed. This report represents the 49th and 50th reported cases in the world's literature.

Adenocarcinoma, Mucinous↗

Severe hyperchloremic acidosis complicating jejunoileal bypass.

In summary, severe hyperchloremic acidosis developed in two patients as a late complication after jejunoileal bypass for morbid obesity. This acidosis was associated with episodes of dizziness, ataxia, headache, weakness, confusion and transient loss of consciousness. Recognition of this symptom complex in the patient with a jejunoileal bypass should suggest metabolic acidosis as a complication of this surgical procedure. Bicarbonate replacement provided prompt, but temporary, improvement in the symptoms and the acidosis. Revision of the intestinal bypass was required for correction. Special studies to rule out renal tubular acidosis were performed and definitely excluded the kidney as a source of the acidosis.

Acidosis↗

Characterization of food binding of vitamin B-6 in orange juice.

There is substantial evidence that natural vitamin B-6 exists largely in a bound form. It has been shown that the principal modes of binding represents an interaction of pyridoxal and/or pyridoxal phosphate with protein moieties. The nature and extent of binding of different forms of the vitamin in orange juice was investigated. Studies employing ultracentrifugation, ultrafiltration and, membrane dialysis of this food product suggested binding to a molecule of less than 3,500 daltons molecular weight. Binding was resistant to protease treatment although susceptible to heat-acid hydrolysis. Separation of pyridoxal, pyridoxine, and pyridoxamine species of the vitamin by ion exchange chromatography was followed by fluorometric analysis with and without preparative hydrolysis. Extensive and equal binding of both pyridoxal and pyridoxine was observed by this method. Thus, the binder(s) of vitamin B-6 in orange juice is a small dialyzable molecule which is heat stable, binds both pyridoxal and pyridoxine and is non-protein in nature.

Citrus↗

Comparative human intestinal bioavailability of vitamin B-6 from a synthetic and a natural source.

Intraluminal perfusion of human jejunum has not been previously reported to demonstrate differences in bioavailability of vitamins from a food product. In this report, a triple lumen tube with a 30 cm study segment was used to study water soluble vitamin absorption in 15 normal subjects serving as their own controls. The intestinal uptake of vitamin B-6 from organ juice (O) and from a synthetic solution (S) perfused at 7.6 ml/minute were compared. In a separate series of perfusions in six subjects, the absorption of a mixture pf pyridoxine, pyridoxal, and pyridoxamine from O and S solutions with and without glucose were compared. Mean vitamin B-6 absorption was significantly greater from S (65% uptake, transport rate 0.71 mug/cm/hour) than from 9 (30% uptake, transport rate 0.40 mug/cm/hour, p less than 0.05). The addition of glucose to S enhanced this difference. Triple lumen intestinal perfusion can be used to discriminate difference in bioavailability of water soluble vitamins from natural and synthetic sources.

Biological Availability↗

Eosinophilic gastroenteritis.

Four patients with eosinophilic gastroenteritis are presented to illustrate the protean manifestations of this disorder. While the cause is unknown, the complications many, and the differential diagnosis often challenging, the treatment is simple and consists of low-dose, alternate-day administration of corticosteroids. Diagnosis depends on gastrointestinal biopsy, which usually can be obtained without surgery.

Biopsy↗

Thrombocytosis in patients with celiac sprue.

In 57% of the patients (12 of 25) seen with celiac sprue, as shown by clinical course and small bowel biopsy, peripheral blood thrombocytosis was present (range: 350,000 to 815,000 platelets per mm(3); mean: 546,000 +/- 44,060 SE). After clinical and histological remission, the platelet counts in these patients fell significantly (range: 188,000 to 300,0000 platelets per mm(3); mean 252,750 +/- 13,211 SE). There was no correlation between thrombocytosis and serum iron, folate, or vitamin B12 levels. Celiac sprue joins inflammatory bowel disease among gastrointestinal disorders as a consideration in the differential diagnosis of thrombocytosis. In these patients, thrombocytosis reflected active disease and was not present during remission. Evaluation of peripheral blood platelets may be useful in the assessment of patients with celiac sprue.

Adult↗

Cholangitis complicating congenital hepatic fibrosis.

A patient with cholangitis complicating congenital hepatic fibrosis is presented. In contrast to most other reported cases, many of whom have been treated surgically, this patient had a benign course. The likelihood that this complication of congenital hepatic fibrosis will respond to appropriate conservative therapy suggests that more aggressive forms of treatment should be reserved for those patients who fail to respond to medical management.

Biopsy, Needle↗

Comparative bioavailability of folate and vitamin C from a synthetic and a natural source.

Intraluminal perfusion of the human small intestine has not been used extensively to study comparative bioavailability of vitamins. In this study a triple lumen tube with a 30-cm study segment was used to measure absorption of water-soluble vitamins from the human proximal jejunum. Fifteen normal subjects served as their own controls to quantitate absorption of folic acid and vitamin C from an orange juice solution and from a solution of synthetic vitamins. Despite a predictably greater water absorption from the glucose containing orange juice solution, the absorption of the two water-soluble vitamins did not differ significantly from the two solutions. Natural and synthetic ascorbate and folate were avidly absorbed in the first 30 cm of jejunum and with the exception of synthetic folate correlated positively with water absorption. This method, previously applied to the absorption of sugars, amino acids, and electrolytes, can be reliably applied to the study of comparative bioavailability of nutrients from food sources. The advantages of triple lumen perfusion over previous methods are: 1) it overcomes the necessity for urine collections in metabolic studies, 2) it can be used to study sites and mechanism of absorption, and 3) it is a direct measurement of absorption capacity.

Adult↗

Lipids and other components of human jejunal and ileal mucosa.

Jejunal and ileal intestinal segments were obtained from patients undergoing laparotomy, from peroral jejunal biopsies, and from fresh cadavers. The excised mucosa was weighed and assayed for total lipids, neutral and polar lipids. The lipid families were separated and identified, and their individual fatty acid composition determined. In addition, DNA, RNA, collagen and total protein were measured.

Collagen↗