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Biomedical subjects

W Leonhardt

Publications and source records attributed to W Leonhardt.

At least 73 records · Page 4Linked to original sources
PubMed1979

[Vascular complications in primary hyperlipoproteinemias (HLP) with special reference to changes in the eye fundus].

The distribution of the types of hyperlipoproteinaemias revealed 2 peaks of frequency, i. e. in the types IIa and IIb corresponding 41% and in the types IV and V corresponding 55%. Weight indices and disturbed glucose tolerance are in the types III-V significantly higher than in the types IIa and IIb. The risk factor hypertension was registered in 34% in the investigation material. The highest prevalence rates for myocardial infarctions were in the patients of the types IIb and III, for PAD in the type III. The addition of hypertension and diabetes mellitus to hyperlipoproteinaemia reveals an exacerbation of the vascular risk. Changes of the fundus oculi, which correspond to the picture of a fundus hypertonicus cause to think of the presence of a hyperlipoproteinaemia in all patients with normotension.

Aged↗
PubMed1979

Basal and stimulated hyperinsulinemia in obesity: relationship to adipose-cell size.

In 17 non-selected, non-hyperlipoproteinemic subjects without overt diabetes both adipose tissue biopsy and an oral glucose tolerance test (50 g) were performed. All persons were weight-stable at the time of investigation. A significant correlation between fasting insulin concentration and mean adipocyte volume was observed, whereas no correlation existed between ideal body weight index and fasting insulin level. Persons with larger adipocytes had elevated basal insulin levels as well as higher and longer lasting increments following the glucose challenge. They also exhibited significantly higher mean glucose levels during the OGTT. When these patients were matched for glucose tolerance with the subgroup having smaller mean adipocyte volumes, the difference in insulin levels was still demonstrable. This study underlines the importance of adipose-cell enlargement regulating basal and stimulated insulin output.

Adipose Tissue↗
PubMed1979

Relationship between adipocyte hypertrophy and metabolic disturbances.

Enlargement of fat cells is known to be a factor stimulating metabolic rates in adipose tissue and thus playing a role in the pathogenesis of certain metabolic disorders. Excessive adipose-cell hypertrophy of the same degree was observed in disturbances of carbohydrate (e.g. in subclinical or maturity onset diabetes) as well as of triglyceride metabolism, despite the fact that body weight in these patient groups was lower than in control subjects (with the exception of subclinical diabetics). Significant correlations between adipocyte volumes and serum triglyceride levels are in agreement with this conception. Similar characteristics of insulin concentrations measured during an oral glucose tolerance test and adipose-cell hypertrophy of the same degree may suggest a comparable influence on the development of carbohydrate intolerance and hypertriglyceridemia. Moreover, our investigations show an increasing of the prevalence of diabetes mellitus, hypertriglyceridemia and hypercholesterolemia up to a Broca Index of 1.2. This points to an extremely high metabolic risk even in people with slight overweight provided the adipocytes are significantly enlarged. Thus, adipocyte size appears to be a good parameter to characterize metabolic impairments.

Adipose Tissue↗
PubMed1978

The adipocyte volume in human adipose tissue: 1. Lipid space, normal and maximum values, and the relation to body weight index.

UNLABELLED: The volume of isolated adipocytes in specimens from the subcutis of the abdomen was measured using the pulse counter technique. The lipid content was determined as esterified fatty acids. RESULTS: (1). Adipocyte enlargement is mainly caused by lipid deposition, despite a slight increase in the lipid free volume. (2). Two cell populations were detected in some cases, with the smaller fraction having a volume between 0.024 and 0.129 nl, which is lower than the common range for human adipocytes. (3). An analysis of large numbers of cells in single specimens revealed the lognormal type to fit the volume distribution better than the normal type. (4). Standard deviations of the lognormal distributions decrease with the mean cell volumes. Calculation by extrapolation shows the maximum adipocyte volume is of the order of 1 nl. (5). Normal curves of the adipocyte volume vs body weight index were set up for 142 test persons. They approach maximum volumes and differ with sex. (6). The normal adipocyte volume is ideal weight persons without metabolic disease is in the order of 0.3 nl.

Abdominal Muscles↗
PubMed1978

Influence of diet composition on insulin output, carbohydrate tolerance and lipid values in primary hypertriglyceridemia (HT).

Hypertriglyceridemic patients generally show a post-challenge hyperinsulinemia. In patients where carbohydrate intolerance coexists, increasing of reactive insulin is relatively diminished and delayed. In a group of 31 hypertriglyceridemic patients these characteristics of insulin increments in peripheral blood during a 50 g OGTT were constant: neither a low-fat (carbohydrate-rich) nor a high-fat (low carbohydrate) isocaloric, weight-maintaining diet had a significant influence on this parameter when compared with a standard diet (protein content unaltered throughout all diet periods). Glucose tolerance was significantly improved after the low-fat, high-carbohydrate diet. The results were neither correlated with the type of dietary inducibility of fasting triglyceride levels in individual cases nor with the sequence of diet periods prescribed. Hyperinsulinemia in hypertriglyceridemic patients is not believed to be the direct consequence of abnormal composition of the antecedent diet.

Carbohydrate Metabolism↗
PubMed1978

The adipocyte volume in human adipose tissue: II. Observations in diabetes mellitus, primary hyperlipoproteinemia and weight reduction.

Body-weight index does not appear suitable as a measure of metabolic risk, since the prevalence of diabetes mellitus, hypertriglyceridemia and hypercholesterolaemia increases only up to a Broca index of 1.2. Attempts were therefore made to demonstrate an abnormal adipocyte enlargement in the subcutaneous adipose tissue of the abdomen in patients suffering from various metabolic disorders. To eliminate the influence of sex and body-weight index, normal curves of the adipocyte volumes in 142 controls were used as basis of comparison. Adipocyte hypertrophy exceeding the degree predicted by the normal curves was observed in patients with subclinical diabetes (n = 20), patients with maturity-onset diabetes (n = 56) and in patients suffering from hyperlipoproteinemia of type IIb (n = 10), type III (n = 8), type IV (n = 42) and type V (n = 24). Excessive hypertrophy could not be detected, however, in juvenile-onset diabetics (n = 11) and in hyperlipoproteinemia type IIa (n = 9). Weight reduction gave further insight into excessive adipocyte hypertrophy. This was effected by reducing caloric intake combined with physical exercise for four to five weeks until 10 per cent of initial weight was lost. Adipocyte shrinking per kg loss of body weight was significantly more pronounced in patients suffering from subclinical diabetes (31 pl/kg,n = 10), from maturity-onset diabetes (26 pl/kg,n = 23) and from hypertriglyceridemia (17 pl/kg, n = 11) in comparison with the controls (7 pl/kg,n = 25).

Adipose Tissue↗
PubMed1977

[Significance of fatty tissue hypertrophy for the metabolic risk].

The prevalence of diabetes mellitus, hypertriglyceridemia, and hypercholesterolemia rised with the weight index until Broca = 1,2; at higher degrees of obesity it remained constant or even slightly decreased Dresden Study). The subcutaneous adipose tissue of the abdomen exhibited against controls an excessive hypertrophy in subclinical diabetics, maturity onset-diabetics and hyperlipoproteinemics of types IIb, IV, and V. With this respect, between these groups there were no significant quantitative differences. Juvenile onset diabetics had abnormal small as well as large fat cells.

Adipose Tissue↗
PubMed1977

Relation of lipoprotein lipase activity in adipose tissue to adipocyte volume and its influence in hypertriglyceridemia pathogenesis.

In the subcutaneous adipose tissue of 20 normal weight and overweight subjects with normo- or hypertriglyceridemia, the relation is examined between the lipoprotein lipase activity (LPLA) per gram adipose tissue and adipocyte volume. The following findings were obtained: 1. Significant positive correlations between the LPLA per gram adipose tissue and the adipocyte volume were ascertained in the groups of subjects having normal triglyceridemia or exhibiting hypertriglyceridemia. 2. The negative relation between the LPLA in the adipose tissue and the triglyceride level in serum described in literature could not be verified. Across a glyceride span of 76 to 600 mg% in serum we found a correlation coefficient of +0.34. 3. It can therefore be assumed that the LPLA per gram adipose tissue with increasing adipocyte volume does not represent an inhibiting factor to the triglyceride in serum breakdown in the development of hypertriglyceridemia.

Adipose Tissue↗
PubMed1976

[Is primary or secondary prevention of diabetes mellitus in hyperliporoteinemia possible under long-term clofibrate therapy?].

The investigations of metabolism explained speak for an improved condition of the carbohydrate metabolism during the first months of the therapy. However, they are not sufficient to prove a preventive effect of clofibrat per se during long-term treatment. Our examinations by means of the glucose infusion test show that on certain defined conditions with intensive general treatment positive effects may be registered, which, however, cannot be reproduced in a large collective during outpatient care. On the contrary, it is to be assumed that the whole therapeutic regime has an influence. Nevertheless, one may establish that the incidence portion of the diabetes manifestation in patients with hyperlipoproteinaemia treated with regadrin corresponds nearly to that one of the average population of Dresden. It is puzzling that the death rate in patients with hyperlipoproteinaemia and diabetic condition of metabolism is significantly higher than in hyperlipoproteinaemia without disturbance of the carbohydrate metabolism.

Clofibrate↗
PubMed1976

Metabolic effects of weight reduction in obese diabetics and nondiabetics.

A weight loss of about 10 kg was acheived by means of individual periods of total fasting, hypocaloric diets and physical activity in three groups of patients: maturity-onset diabetics, patients with pathological OGTT and overweight persons with normal OGTT. Adipocyte volume decreased in all groups, glucose tolerance improved. IRI curves showed a significant overall lowering and FFA concentrations during OGTT were dimished.

Adipose Tissue↗
PubMed1975

[Importance of adipose tissue hypertrophy for the pathogenesis of maturity-onset diabetes].

In 56 maturity-onset-diabetics and 20 test persons with pathologic glucose tolerance were established significantly larger volumes of adipocytes than in 142 test persons with normal glucose tolerance and normal serum triglycerides. The differences could only be proved taking into consideration the influence of the index of ideal weight and the difference of sex. The pathogenetic importance of the excessive hypertrophy of adipose tissue is discussed on the basis of the increased turnover rate of free fatty acids.

Adipose Tissue↗