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Biomedical subjects

G Heller

Publications and source records attributed to G Heller.

At least 163 records · Page 9Linked to original sources
PubMed1981

[Comparison of radioimmunological methods for the determination of basal serum TSH levels].

In our experience the routine measurement of basic serum TSH levels is of great value in diagnosis and therapy control of thyroid diseases. However, the reliable differentiation of normal and suppressed TSH levels requires a very sensitive and accurate radioimmunoassay. Based on a commercially available TSH-RIA-kit it is demonstrated that the prolongation of several incubation-times as well as the use of thoroughly selected, pooled "TSH-poor" human sera for establishing the standard dilutions result in a pronounced improvement of the RIA. Further assay improvement is achieved by a higher dilution of the first antibody and by reduction of the added tracer-amount, provided that the TSH used for labelling is of high quality, that the labelling-procedure is carried out under mild conditions and that the 125-I-TSH is prepared carefully by high-resolution-gel chromatography. The resulting RIA can be characterized by a between-assay coefficient of variation: 5-10% in the so-called normal range (0.8-5.0 mU TSH/l), by a lower detection-limit: 0.2 mU TSH/l and by a 50%-intercept: 2.0 mU TSH/l.

Humans↗
PubMed1977

[Effect of various dietary carbohydrates on supplementary cholesterol].

The effect of addition of different carbohydrates (starch, glucose, fructose) to the feed was investigated using the experimental animal. Additionally, the admixture of cholesterol and of cholesterol plus cholic acid was tested. Fructose (70% of the feed) causes a slight increase in serum triglyceride concentration and a very slight increase in triglyceride concentration in the liver. Fructose and to a lesser degree glucose cause an increase in pyruvate kinase activity in the liver. The activity of glucose-6-phosphate dehydrogenase is increased slightly following high-dosed glucose, whereas the increase is very pronounced following fuctose-rich feed. The admixture of cholesterol (with cholic acid) causes a decrease in glucose-6-phosphate dehydrogenase activity up to 70%. The activity of glutamate dehydrogenase is decreased also following cholesterol admixture. A fructose-rich diet causes a slight degree of hyperlipemia with a metabolic situation similar to a latent diabetic state. This effect is greatly intensified by the addition of cholesterol and cholic acid to the diet of the rats. Especially striking was the increase in serum-free-fatty-acid concentrations in all groups of animals. This is speculated to be a sign of insulin deficiency. The so-called "carbohydrate-induced hypertriglyceridemia" is obviously intensified within a short period by the admixture of cholesterol plus cholic acid to the experimental diet.

Animals↗
PubMed1975

[The importance of the carbohydrate portion in a synthetic diet].

The influence of an almost fat-free and carbohydrate-rich diet on different serum parameters was investigated in human volunteers. These studies were supplemented by animal experiments where the effects of different additions of carbohydrates were compared. In human volunteers the fat-free and carbohydrate-rich diet caused a decrease in serum cholesterol concentration. This effect was especially seen when the initial cholesterol values were elevated. Exchange of the glucose carbohydrates (consisting predominantly of oligosaccharides) by frutose or by surose was without an influence on serum concentrations of cholesterol or triglycerides. No signs of carbohydrate-induced hyperlipemia were seen in human volunteers. Only under extreme conditions (60% fructose in the diet) a moderate increase in serum triglyceride concentration was found in animal experiments. However, serum cholesterol was unaltered even under these conditions. Additionally, no significant influence on fat concentration in the liver (triglycerides or cholesterol) was seen. Only using an imbalanced diet (80% glucose or 80% fructose) a slight increase in fat content of the liver and a moderate hypertriglyceridemia were observed. The concentration of serum cholesterol remained unaltered, cholesterol concentration in the liver diminished slightly. These experimental results are considered as evidence that only the extreme situation of a food imbalance (or hypernutrition) can cause a so-called carbohydrate-induced hyperlipemia.

Adult↗