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Biomedical subjects

K Zwiauer

Publications and source records attributed to K Zwiauer.

At least 19 recordsLinked to original sources
PubMed2004

Decrease of plasma apolipoprotein A-IV during weight reduction in obese adolescents on a low fat diet.

OBJECTIVE: Apolipoprotein (apo) A-IV is an antiatherogenic apolipoprotein, which may be involved in the regulation of food intake. Plasma apoA-IV is elevated in human obesity and apoA-IV polymorphisms have been associated with the extent of obesity. Our aim was to determine the effects of weight loss on plasma apo-IV in obese adolescents and to examine the relation of apoA-IV with the degree of obesity. DESIGN: Longitudinal intervention study of a low fat hypocaloric diet conducted in a dietary camp. SUBJECTS: Two groups of obese adolescents (n=47 and n=29), age: 12.7+/-1.7 and 11.7+/-2.6 y, relative body mass index (RBMI): 168+/-24 and 175+/-34%, respectively. MEASUREMENTS: Plasma total apoA-IV, apoA-I, apoB, plasma distribution of apoA-IV, leptin, lipids, and lipoproteins before and after 3 weeks of weight reduction. RESULTS: Plasma apoA-IV decreased from 11.5+/-4.1 mg/dl before to 6.7+/-2.2 mg/dl after weight reduction in the first group (P<0.001) and to a similar extent in the second group. The relative amount of lipid-free apoA-IV and apoA-IV associated with apoA-I increased slightly, whereas apoA-IV associated with lipoproteins devoid of apoA-I decreased. ApoA-IV levels before and after weight reduction and the changes in plasma apoA-IV did not independently correlate with RBMI, weight loss, or plasma leptin. CONCLUSION: Plasma apoA-IV decreases markedly in overweight adolescents undergoing short-term weight reduction. The decrease is not directly related to the degree of weight loss and the mechanisms underlying this reduction remain to be clarified.

Adolescent↗
PubMed1999

Relation of plasma leptin to lipoproteins in overweight children undergoing weight reduction.

BACKGROUND: In obese children, plasma leptin is elevated and correlates with the body mass index (BMI). In obese adults, plasma leptin decreases during weight reduction. Since the leptin system changes dynamically in puberty, we asked whether weight reduction in obese adolescents has similar consequences for plasma leptin as in overweight adults. In plasma, a portion of leptin is bound to several as yet uncharacterised proteins. We therefore studied the possible association of leptin with plasma lipoproteins. SUBJECTS AND METHODS: We measured plasma leptin, lipoprotein cholesterol and apolipoproteins (apo) A-I and B in 34 obese children (age 12.5+/-1.9 y, relative BMI 165.0+/-28.1%) before and after three weeks of weight reduction in a dietary camp. Lipoprotein binding of endogenous and exogenously radiolabelled leptin was studied by preparative ultracentrifugation. RESULTS: Plasma leptin was higher in obese children than in normal weight controls and fell from 16.5+/-9.8 ng/ml to 10.0+/-8.6 ng/ml after weight reduction (P < 0.001). In multivariate regression, relative BMI and apoA-I were significant predictors of baseline leptin and accounted for 38% (P = 0.003) and 15% (P = 0.006) of the variance of baseline leptin concentrations in obese children. Only the difference in plasma high-density lipoprotein (HDL)-cholesterol independently predicted the change of plasma leptin that was associated with weight reduction, explaining 29% of the variance of leptin changes (P = 0.0032). A substantial portion of both endogenous and exogenously labelled leptin was recovered with HDL isolated by ultracentrifugation. CONCLUSIONS: We conclude that plasma leptin decreases in overweight children undergoing short term weight reduction. In obese children, plasma apoA-I and HDL-cholesterol are independent predictors of leptin concentrations during weight loss, respectively. In addition, HDLs transport a variable portion of leptin in the circulation.

Adult↗
PubMed1998

[Therapy of obesity in childhood and adolescence].

Major therapeutic goal of the treatment of childhood obesity is to prevent immediate and long-term adverse health consequences. In obese adults weight loss is always necessary to achieve normal or tolerable weight. During infancy and childhood keeping body weight constant while body height increases can be acceptable. If substantial body weight loss in children and adolescents is mandatory, it is necessary to consider the special physiological peculiarities of the growing organism during weight reduction. The main cornerstones of therapeutic regimens for long-term weight reduction in childhood obesity are: eating behaviour modification resulting in changes in food selection, dietary fat intake and caloric restriction, instruction to increase physical activity in everyday life and guidance to an active life style. Integrated therapeutic programs including these components based on behaviour modification have been shown to be the most successful in long-term effect on body weight. Treatment of obesity is most successful if realistic goals are set, if parental support is strong and if behaviour therapy is provided during the course of treatment to help both child and parent achieve these goals.

Adolescent↗
PubMed1997

The effect of weight reduction on the surface electrocardiogram: a prospective trial in obese children and adolescents.

OBJECTIVE: Controversial data exist on the effect of obesity and weight reduction on surface electrocardiographic parameters. The purpose of this study was to analyze electrocardiograms of obese children in the course of short-term weight reduction. DESIGN: Prospective trial over a period of three weeks with a conventional low calorie diet containing a mean of 525 +/- 109 kcal. SUBJECTS: Thirty-three children, 17 girls and 16 boys with a mean age of 12.2 +/- 1.7 y and an overweight of 25.4-102%, mean 54.2 +/- 15.6%. MEASUREMENTS: Before the onset of therapy and thereafter, body weight, blood chemistry and 12 lead electrocardiographic evaluations were performed. RESULTS: The mean loss of body weight was 5.7 +/- 1.6 kg resulting in a mean decrease in overweight of 13.5 +/- 3.4%. Blood chemistry analyses revealed no significant changes except for cholesterol, triglycerides and uric acid. All electrocardiograms were within normal limits, however, a change in the electrocardiographic pattern was noted after weight loss. Heart rate (84 +/- 14 vs 64 +/- 11 beats per min, P < 0.0001) and QT interval (418 +/- 20 msec vs 391 +/- 22 msec, P < 0.0001) decreased and there was a tendency towards a rightward shift of the frontal plane QRS axis and a leftward shift of the horizontal plane QRS axis. CONCLUSION: Weight reduction in obese children and adolescents is associated with significant changes in the electrocardiographic pattern. These changes may only be detected by intraindividual comparison. Reduction of heart rate and shortening of the QT interval in the course of weight reduction may be of clinical significance by reducing the cardiovascular risk profile, including the risk of potentially fatal arrhythmias in obese subjects.

Adolescent↗
PubMed1991

Inverse relationship between diastolic blood pressure and urinary excretion of potassium in girls aged 8 to 9 years--a preliminary communication.

In order to investigate the association of urinary excretion of sodium and potassium with blood pressure, 72 prepubertal healthy children between 8 and 9 years were investigated in a cross sectional study. We determined anthropometric data, diastolic (DBP), and systolic blood pressure (SBP) and urinary excretion of sodium and potassium in 24-hour urine samples. No relationship was found between urinary sodium or potassium excretion and systolic or diastolic blood pressure, neither with regard to simple, nor multiple regression analysis. However, on simple linear and multiple regression analysis a significant inverse association between the excretion of potassium and diastolic blood pressure (r = -0.53; p less than 0.01 and r = -0.60; p less than 0.001) was observed in girls. From our data we conclude that in normal weight, healthy children urinary excretions of sodium and potassium are not associated with systolic blood pressure. However, a high 24-hour urinary excretion of potassium might be associated with lower diastolic blood pressure in prepubertal girls.

Anthropometry↗
PubMed1990

[Cholesterol, triglycerides and lipoproteins in the serum of healthy, normal weight children between 6 and 12 years of age].

Serum cholesterol, triglycerides and lipoproteins were investigated in 276 healthy, prepubertal children and adolescents of normal weight aged 6 to 12 years. The results were evaluated on the basis of the guidelines of the Austrian Cholesterol Consensus Conference 1988 and according to the 90th and 95th percentiles of the Lipid Research Clinics (LRC) data. A relatively high percentage of the probands revealed cholesterol concentrations which could be classified as "risk" (50% of the female and 53% male probands) or "high risk" (39% of the girls and 25% of the boys). Classifying the cholesterol data according to the LRC criteria 46% of the girls and 41% of the boys exceeded these "cut off" values of the 90th percentile. Our data show that the mean serum cholesterol concentrations in healthy children and adolescents of normal weight--like in other European countries--are in a region concomitant with the category in adults which is associated with an increased risk for cardiovascular diseases. We assume that apart from genetic factors a high fat intake might play a predominant role in causing these raised levels.

Austria↗
PubMed1990

Relationship between body fat distribution and blood lipids in obese adolescents.

Associations between body fat distribution, measured by waist/hip circumference ratio (WHR), and plasma lipids and lipoproteins were examined in 74 grossly obese adolescents. WHR was positively correlated in adolescent girls with total triglycerides (r = 0.44, P less than 0.01), total cholesterol (r = 0.49, P less than 0.001), and LDL-cholesterol (r = 0.59, P less than 0.001). In adolescent boys no correlation was found for total cholesterol but there were correlations for triglycerides (r = 0.41, P less than 0.05), LDL-cholesterol (r = 0.49, P less than 0.001), HDL-cholesterol (r = -0.66, P less than 0.001) and the ratio cholesterol/HDL-cholesterol (r = 0.62, P less than 0.001). Waist/hip ratio was not correlated with BMI or percentual overweight in obese girls, but a significant association was found in obese boys for both (r = -0.46, P less than 0.03 and r = 0.53, P less than 0.02). These results indicate that in obese girls a prevalence of abdominal fat distribution is correlated with increased triglycerides, serum cholesterol and LDL-C. In male adolescents total cholesterol is only slightly influenced but HDL-C concentrations are lower and LDL-C and the ratio CHOL/HDL-C higher.

Adipose Tissue↗
PubMed1989

No reduction of high density lipoprotein2 during weight reduction in obese children and adolescents.

The effects of a 3 week weight reduction regimen on lipids and lipoproteins, in particular high density lipoprotein (HDL)-subfractions in 61 grossly obese children and adolescents (37 females and 26 males) aged 11-15 years were studied. Dietary treatment resulted in a significant weight reduction of initial body weight of 9.6 +/- 2.1%, a highly significant decrease in cholesterol, low density lipoprotein cholesterol (LDL-C) and HDL-C (P less than 0.001), as well as a significant reduction in triglycerides, HDL3 and Apolipoprotein B concentrations (P less than 0.01). HDL2 concentrations remained almost constant. It is concluded that HDL reduction during a weight reducing regimen in adolescents does not result in a decrease of the antiatherogenic HDL2 subfraction.

Adolescent↗
PubMed1989

Plasma concentrations of free amino acids during 3 weeks treatment of massively obese children with a very low calorie diet.

Eight grossly obese children (2 girls, 8 boys, age 12.6 +/- 2.1 mean +/- SD years, mean overweight 73.3 +/- 14%) were treated for 3 weeks with a very low calorie diet (VLCD), containing 1022 kJ/240 kcal, 33 g protein, 25.5 g carbohydrate and 0.7 g fat/day. Mean weight loss after 3 weeks was 9.47 +/- 2.8 kg and mean nitrogen loss was calculated to be 113.3 +/- 71.2 g. While serum electrolytes, enzymes, glucose, urea and creatinine remained almost unchanged, distinct alterations of 23 free amino acids in plasma could be observed. A transient increase of plasma valine, leucine, isoleucine and alpha-aminobutyrate during the 1st week was followed by a constant fall in the 2nd and 3rd week. Glycine, proline, serine and threonine showed a progressive increase, while cystine, histidine and, above all, alanine decreased, the diminution of alanine being most rapid during the 1st week. No significant changes were observed in plasma concentrations of arginine, asparagine, aspartic acid, citrulline, glutamic acid, glutamine, lysine, tyrosine, ornithine, phenylalanine and taurine. Total plasma amino acid content did not change during diet compared to the pre-diet period. The behavior of plasma amino acids shows a typical pattern within four groups, reflecting various interorgan substrate fluxes during hypocaloric dieting.

Adolescent↗
PubMed1989

Adipogenic activity in sera from obese children before and after weight reduction.

The adipogenic and mitogenic potentials of sera obtained from obese children before and after weight reduction and from lean control subjects were studied in clonal 3T3 L1 fibroblasts. The sera from the lean (n = 14) and obese (n = 12) children under habitual diet contained similar adipogenic activity. However, when the obese children underwent a weight-reduction program for 3 wk (600 kcal/d), the potential of their sera to stimulate glycero-phosphate dehydrogenase, an index of adipogenic activity, was significantly reduced by 32% (p less than 0.01). Similarly, the mitogenic activity of these sera decreased significantly (202 +/- 15 vs 231 +/- 27 micrograms per dish, p less than 0.01). Testing pooled sera from the different groups in cultured rat adipocyte precursor cells gave similar results. This study suggests that human childhood-onset obesity is not accompanied by increased circulatory factors involved in the formation of new fat cells. The adipogenic and mitogenic activity of sera from obese children may be influenced by long-term dietary restriction.

Adipose Tissue↗
PubMed1989

24 hours electrocardiographic monitoring in obese children and adolescents during a 3 weeks low calorie diet (500 kcal).

Twenty-four hour electrographic recordings were made on 36 grossly obese children and adolescents during a 3-week weight reduction regimen with a 525 kcal (2196 kj) mixed diet at weekly intervals. One hundred and ten Holter ECGs were analysed. Weight loss during the treatment was calculated to be 5.7 +/- 1.6 kg. Average and minimal heart rate decreased constantly throughout the study period from 83.9 +/- 9 to 75 +/- 9/min and 53 +/- 6 to 45 +/- 6/min, respectively (P less than 0.01, P less than 0.005). During the second week maximal heart rate increased significantly but returned to baseline values in the third week. Neither before nor during the period of therapy were any dysrhythmias monitored. Dietary regimens containing 500-700 kcal, based on a mixed composition of foods with sufficient amounts of minerals, can be regarded as a safe therapeutic tool in the treatment of obese children and adolescents.

Adolescent↗
PubMed1989

[The significance of carbohydrates in reducing diets].

The importance of carbohydrates in weight reducing regimens on different metabolic aspects is shown by comparing the effects of two extreme dietary regimens: 'ketogenic' diet, consisting primarily of proteins and fat and the 'mixed' diet, containing mainly carbohydrates. The effects on hunger and satiety, weight loss and nitrogen balance are discussed as well as influences on electrolytes, body fluids and the sympathetic system. Hormonal changes of the two dietary regimens and the impact on mood and subjective acceptance are compared. Though no recommendation for a particular dietary regimen is given, the different implications on the parameters described are pointed out.

Appetite↗
PubMed1989

[Follow-up study of severely overweight adolescents 4 years following inpatient weight loss with a low calorie protein-carbohydrate diet].

Very low calorie protein/carbohydrate diets have proved to be efficient and safe in the treatment of obesity in childhood and early adolescence. The follow-up study at issue shows that subsequent to short-term therapy no further reduction in weight is to be expected without adequate care following the diet. Between 1980 and 1983, 27 adolescent patients were treated for severe obesity (78.12% +/- 18.3% overweight, mean +/- s.e.m.) at the metabolic ward of the department of pediatrics, University of Vienna. The administration of a very low calorie protein/carbohydrate diet (VLCD) for 26 (+/- 7) days led to a considerable reduction in overweight (8.1 +/- 2.9 kg). On dismission the percentual overweight had decreased to 59.4 (+/- 24)%. After 4.4 (+/- 0.7) years the weight of 11 of the 27 patients could be controlled, 10 patients refused further cooperation and the remaining 6 could not be addressed. The body mass index (weight/height) had risen from 29.4 (+/- 1.2) to 43.0 (+/- 6.0) with 10 of 11 patients, corresponding to a percentual overweight of 88.2 (+/- 18.1)% at the follow-up date. Only one girl had reduced overweight by 45%, the BMI had fallen from 33.9 to 27.1. Furthermore, our data suggest that obesity induces a significant increase in blood pressure in adolescents. This rise is apparently independent of the age related increase in blood pressure and revertible by weight loss. The results we have to hand show that long-term weight reduction has only been achieved in 1 of 11 cases, with none of the adolescents having participated regularly in an outpatient after-care program.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

Characterization of an adenine phosphoribosyltransferase deficiency.

A case of adenine phosphoribosyltransferase deficiency in a 4.5-yr-old boy is described. A pedigree of the family, enzyme activities and kinetic data of the enzyme in the propositus and the carriers of the defect are presented. The amount of enzyme in the patient was about 2% of that in healthy subjects and correlated well with the amount of immunoreactive protein. Our data indicate that the patient's enzyme is not affected in its catalytic properties, but is made in far reduced amounts.

Adenine Phosphoribosyltransferase↗
PubMed1988

[Diffuse xanthogranulomatous pyelonephritis in childhood].

Xanthogranulomatous pyelonephritis is a rare disease and rare cause of suppurative proliferative pseudotumor in children. An accurate diagnosis is difficult because of its clinical, radiological, sonographical and pathologic-anatomical similarities to renal tuberculosis. After removing the diseased kidney the prognosis is excellent. A 6-year old boy with xanthogranulomatous pyelonephritis is reported.

Child↗