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M D Levitt

Publications and source records attributed to M D Levitt.

223 records · Page 13Linked to original sources
PubMedDate not supplied

Hypothesis: metabolic activity of the colonic bacteria influences organ injury from ethanol.

Incubation of human fecal homogenates with ethanol (0.078 gm per dl) resulted in accumulation of increased quantities of higher alcohols and other unidentified metabolites when compared with homogenates incubated without ethanol. Studies in rats demonstrated nearly perfect equilibration between blood and colonic luminal ethanol suggesting that the colonic flora in alcoholics is chronically exposed to ethanol concentrations in the range used in the homogenate experiments. The higher alcohols produced by the homogenates were rapidly absorbed from the colon. We hypothesize that, when exposed to ethanol, the colonic flora produced toxic compounds which are absorbed and influence the body's response to ingested ethanol. Individual differences in this bacterial metabolism may account for the wide individual differences in susceptibility to ethanol-related organ injury.

Animals↗
PubMedDate not supplied

Colonic concentrations of hydrogen and methane following colonoscopic preparation with an oral lavage solution.

Explosions are a rare complication of electrocautery in the colon. The cause of these explosions is ignition of gas containing hydrogen (greater than 4%) or methane (greater than 5%), and oxygen. Hydrogen and methane are products of colonic bacterial metabolism. Oral solutions used for colonoscopy preparation are designed to cleanse the colonic lumen but provide no substrate for fermentation reactions. In 52 patients undergoing colonoscopy, gas samples were collected from the right, transverse, and left colon and analyzed for hydrogen, methane, oxygen, and carbon dioxide. The highest hydrogen and methane concentrations were 0.6% and 0.7%, respectively, less than 16% of the explosive level. Oxygen and carbon dioxide concentrations were close to those of air, suggesting that the bulk of colonic gas was air infused during the procedure. We conclude that the concentrations of explosive gases are well below the hazardous levels when oral colonic cleansing solutions and standard colonoscopic procedures are employed.

Administration, Oral↗
PubMedDate not supplied

Comparison of predictive capabilities of diabetic exchange lists and glycemic index of foods.

To determine whether the diabetic exchange lists or the glycemic index of foods better predicts postprandial responses to carbohydrate-containing foods eaten as part of a mixed meal, three test meals were developed and fed to 12 subjects with non-insulin-dependent diabetes mellitus (NIDDM) and 13 healthy subjects. Each test meal contained exactly the same exchanges (1 milk, 4 starch, 2 fruit, 2 meat, 3 fat, 1 vegetable). In one meal, foods of high glycemic index (GI) were used, in a second meal, foods of intermediate GI were used, and in a third meal foods of low GI were used. The total GIs of the meals were: high, 184; intermediate, 131; and low, 107, thus predicting responses to intermediate and low GI, which were 71 and 58%, respectively, of the responses to high GI. Although some of the observed differences in the glycemic responses to the test meals were statistically significant, primarily in healthy subjects, the differences were usually much less than predicted by the GIs of the meals. In NIDDM subjects, peak postprandial plasma glucose, plasma glucose area, plasma glucose area increment, and mean plasma glucose responses after intermediate and low GI were greater than 90% of the corresponding responses to high GI. In healthy subjects, only the plasma glucose area increment after the low-GI meal was close to the predicted response. High GI produced significantly greater insulin responses than low GI in healthy subjects. We conclude that the diabetic exchange lists more accurately predict postprandial responses to carbohydrate-containing foods eaten as part of a mixed meal than does the GI of foods.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Nutritional and therapeutic aspects of fermented dairy products.

In summary, evaluation of the nutrient composition of fermented dairy foods indicates that, like milk, they are good sources of protein, calcium, riboflavin and vitamin B12. Fermented dairy foods are also a good source of folic acid due to microbial synthesis. The absorption of lactose in yogurt is enhanced by the presence of bacterial lactase. Like their nonfermented counterparts, fermented dairy foods may be chosen within a broad range of fat and calorie levels. Fermented and low fat milk products contain only forty to sixty-three calories per 100 grams, whereas sour cream, like sweet cream, is high in fat and contains over two hundred calories per 100 grams. Some fermented dairy foods have antibiotic or antitumor activity in vitro or in laboratory rats. The relevance of these findings to the treatment of human diseases is unknown.

Animals↗