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Biomedical subjects

T Stein

Publications and source records attributed to T Stein.

At least 73 records · Page 4Linked to original sources
PubMed1981

Effect of vegetarianism on the zinc status of pregnant women.

The zinc status of 12 pregnant vegetarian women, six pregnant nonvegetarian women, and five nonpregnant vegetarian women was evaluated. Zinc intake was calculated from 3-day dietary records. Hair, urinary, and nonfasting plasma samples were collected during an interview. Dietary, plasma, urinary, and hair zinc levels did not differ significantly between the pregnant vegetarians and nonvegetarians. But plasma zinc was about 21% lower in the pregnant women than the nonpregnant women even though the pregnant women consumed about twice as much zinc as the nonpregnant women. The data suggest that the parameters of zinc status studied were affected by pregnancy more than ovo-lacto vegetarian dietary habits.

Adult↗
PubMed1981

Studies on the characterization of the linkage-region between polysaccharide chain and core protein in bovine corneal proteokeratan sulfate.

1) A new method of enrichment of the linkage-region in corneal proteokeratan sulfate is described, which consists of desulfation of peptidokeratan sulfate, followed by chromatography on Con A-Sepharose 4B and enzymatic degradation with beta-D galactosidase and beta-N-acetyl-D-glucosaminidase. 2) After permethylation, hydrolysis, reduction with sodium borohydrid and acetylation gas chromatography/mass spectrometry analyses were performed. The followings products could be detected as their peracetates: 2,3,4-tri-O-methylfucitol; 2,3,4,6-tetra-O-methylmannitol; 3,4,6-tri-O-methylmannitol; 2,4-di-O-methylmannitol; 2,3,4,6-tetra-O-methylgalactitol; 2,4,6-tri-O-methylgalactitol; 2,4-di-O-methylgalactitol. 3) The results point to the presence of a branched linkage region in the proteokeratan sulfate molecule with one mannose as the branching point and two mannose residues as the starting point of two disaccharide chains.

Animals↗
PubMed1979

Cystic fibrosis and hearing loss.

The mucosal epithelium of the middle ear and Eustachian tube is in direct continuity with the upper respiratory tract. Since the otolaryngological aspects of cystic fibrosis (CF) are dominated by involvement of the paranasal sinuses, it might be assumed that children with CF would be expected to have a higher than usual incidence of middle ear disease. Eighty patients who were afflicted with CF had audiological evaluations, which consisted of hearing threshold levels (250 to 8,000 Hz) and speech and impedance audiometry. We found no greater incidence of a conductive or sensorineural hearing loss in patients with CF when compared with a normal age-adjusted population.

Acoustic Impedance Tests↗
PubMed1979

Changes in intrarenal blood flow during sepsis.

The intrarenal hemodynamics of nine dogs were studied using 15 micron diameter plastic radioactive microspheres labeled with either 85Sr or 141Ce injected before and with the alternative isotope injected 30 minutes after the induction of sepsis. Total renal microsphere trapping increased by 30.6 per cent, p less than 0.01, after the induction of sepsis. The glomerular filtration rate was unchanged. Microsphere trapping in the outer and inner cortex increased by 36.9 per cent, p less than 0.005, and by 20.3 per cent, p less than 0.05, respectively, reflecting increased renal blood flow. Fractional renal microsphere distribution in the outer cortex increased from 70.0 to 73.4 per cent, p less than 0.01, following the induction of sepsis. These data confirm that sepsis results in renal vasodilatation. In addition, a shift in intrarenal blood flow to the outer cortex was demonstrated. Since the outer cortex is perfused with blood which first passes through the inner cortex, it can be hypothesized that renal blood flow in septic states may be passing through dilated glomerular vessels unable to trap microspheres in the inner cortex or passing through precapillary open arteriovenous shunts, or both, thereby bypassing inner cortical functioning glomeruli. This may partly explain the decreased renal function associated with increased renal blood flow in septic states.

Animals↗
PubMed1979

Renal vascular effects of stroma and stroma-free hemoglobin.

To assess the renal effects of hemoglobulin infusion, intrarenal hemodynamics were studied in 14 dogs using radioactive microspheres following the infusion of hemoglobin and stroma. Fractional renal microsphere distribution in the outer cortex remained at control levels following the infusion of hemoglobin. When the infusion of stroma followed, there was a 4.3 per cent, p less than 0.01, increase in the outer cortex microsphere distribution at the expense of the inner cortex, p less than 0.05. When the order was reversed, the stroma suspension being infused first, again there was a significant increase in the outer cortex distribution--6.1 per cent; p less than 0.01. When the infusion of hemoglobin followed, the outer cortex microsphere trapping reverted to control levels. These data revealed no effect upon intrarenal blood flow following the infusion of hemoglobin. The previously reported renal toxicity of hemoglobin infusion is, therefore, probably secondary to contamination with stroma. Hemoglobin should be further investigated for use as an ideal resuscitation fluid.

Animals↗
PubMed1978

The effect of jejunoileal bypass on bile composition and the formation of billiary calculi.

In our series of 101 patients with small bowel bypass for morbid obesity, nine developed biliary calculi postoperatively during a mean follow-up of 29.6 months. The development of gallstones depends in part on biliary cholesterol saturation and on the zeta potential of bile. In eight consecutive patients, the lithogenicity of bile was assessed by the methods of Small, Swell and Isaksson, which are dependent on cholesterol saturation. Postoperatively, the lithogenic score decreased in six and increased in two patients, one of which developed gallstones. Taurine bile salt conjugation tends to prevent aggregation of micelles by increasing the zeta potential. The biliary glycine/taurine ratio increased (p less than 0.05) from 4.6 to 5.9 postoperatively. These results suggest that the increased incidence of cholelithiasis following small bowel bypass is not only due to a relative change in bile composition but is probably more significantly due to an increase in the biliary glycine/taurine ratio and a consequent decrease in the biliary zeta potential.

Adult↗
PubMed1978

High-speed drill noise and hearing: audiometric survey of 70 dentists.

Many dentists believe that noise generated from high-speed drills results in a significant loss of hearing. Audiological evaluations, consisting of hearing thresholds at eight frequencies (500 to 800 Hz) and impedance audiometry, were done of 70 dentists from eight specialties. No statistical decrease in hearing thresholds appeared in either the speech or high frequencies when the dentists were compared with a normal, age-adjusted population.

Adult↗
PubMed1978

Studies on the role of serotonin in gastric pepsin secretion.

The effect of serotonin depletion and replacement on histamine stimulated pepsin secretion was evaluated from Heidenhain pouches of dogs. Serotonin depletion by reserpine or antagonism by l-methyl-d-lysergic acid butanolamide significantly reduced histamine stimulated pepsin secretion. Serotonin replacement by 5-hydroxytryptophan elevated pepsin secretion, despite the prior depletion by reserpine. The data suggest that serotonin is a stimulator of histamine stimulated pepsin secretion in denervated gastric pouches in dogs.

5-Hydroxytryptophan↗
PubMed1977

The effect of serotonin on pepsin inhibition by duodenal fat.

The purpose of these studies was to evaluate the possible role of serotonin on pepsin secretion. The results of our data suggest that serotonin is a stimulator of pepsin secretion since (a) pretreatment with reserpine (which depletes serotonin stores) abolished the stimulatory effect of histamine on pepsin secretion; (b) pretreatment with UML-491 (a serotonin blocking agent at the effector level) augmented the pepsin inhibition induced by the intraduodenal infusion of fat, and (c) 5-hydroxytryptophan (a serotonin precursor) caused a significant stimulation of pepsin secretion. The mode of action of serotonin is probably by a direct hormonal action on the gastric chief cells.

Animals↗
PubMed1977

Abnormalities of liver function following extensive jejunoileal bypass and resection in rats.

A greater than 90% jejunoileal bypass similar to the type performed in man for morbid exogenous obesity was performed in 70 adult female Wister rats; in an additional 70 rats a greater than 90% jejunoileal resection was performed. The control group consisted of 46 rats, which were not subjected to any experimental measures. Following operation the bypass group demonstrated a significantly greater weight loss than did the resection group. Total plasma protein, albumin, and glutamic oxalacetic transaminase all decreased from the control in both the resection and bypass groups; the decrease, however, was more significant in the bypass than in the resected group. These results suggest the possible production of a hepatotoxic factor in the excluded small bowel segment.

Alanine Transaminase↗
PubMed1976

Studies on the effect of small bowel bypass for massive obesity on gastric secretory function.

Gastric secretory function was studied in 20 morbidly obese patients both before and after jejuno-ileal bypass. The mean postoperative weight loss was 99.2 pounds during a mean postoperative followup period of 12.6 months. The gastric secretory values we studied included basal and histalogstimulated volume, pH, concentration, and output. No statistically significant changes were observed in any of these variables. Therefore it is suggested that jejuno-ileal bypass, as performed for morbid obesity, is probably not an ulcerogenic procedure.

Adolescent↗
PubMed1976

The pathogenesis of diarrhea after bypass of the small intestine.

Certain aspects of the pathogenesis of the diarrhea after bypass procedures of the small intestine for obesity have been evaluated. In the late postoperative period, a significant increase occurred in fecal weight and in fecal bile salt and free fatty acid output. There was a significant direct correlation between fecal weight and fecal bile salt output. There was no significant correlation between fecal weight and fecal fatty acid output. This suggests that, after bypass procedures of the small intestine, bile salts play a more significant role in the pathogenesis of diarrhea than do free fatty acids.

Bile Acids and Salts↗