OBJECTIVE: To examine the relationships between the distribution and composition of subfractions of very low density (VLDL), low density (LDL) and high density (HDL) lipoproteins and central fat deposition as measured by the waist-to-hip ratio (WHR). DESIGN: Participants (n 62, 44 women and 18 men; body mass index (BMI) ! 25.0) were recruited from those consecutively attending the outpatient obesity clinic at the University Hospital, Geneva. MEASUREMENTS: Lipoprotein subfractions were isolated from fasting blood samples by cumulative¯otation or density gradient ultracentrifugation. Concentration and composition were analysed as a function of obesity indices. RESULTS: There were signi®cant correlations between the WHR and the pro®les of the three major lipoprotein subclasses. Central obesity was associated with larger VLDL, small, dense LDL and lower levels of HDL-2 independently of other indices of obesity and plasma triglycerides. Central obesity was also signi®cantly and independently associated with compositional anomalies, speci®cally an increased free cholesterol content of VLDL and LDL. CONCLUSIONS: Central body fat was associated with modi®cations of an atherogenic nature to lipoprotein distribution and composition. The data are consistent with an impact of body fat distribution on cardiovascular disease (CVD) via the agency of modi®ed lipoprotein metabolism independently of raised triglycerides.

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Objectives: To evaluate energy balance after three isocaloric oral loads of different composition and to establish possible relationships between the substrates oxidative patterns and the modi®cations of insulin and free fatty acids (FFA) plasma pro®les. Design: Each subject received, in a randomized order, three oral loads of 2658 AE 45 kJ (636 AE 11 Kcal) either as glucose, lipids (cream) or a mixture (glucose cream). Setting: The experiments were performed at the University Hospital of Geneva. Subjects: Ten normal body-weight volunteers. Methods: Energy expenditure (EE) and substrates oxidation were measured by indirect calorimetry during 8 h following each load. Plasma glucose, insulin and FFA were also measured. Results: EE was 1776 AE 107, 1818 AE 125 and 1785 AE 117 KJ over 8 h after glucose, mixed and lipids load, respectively. Glucose oxidation was the highest after oral glucose as compared to mixed and lipids load, while the highest value of lipids oxidation was measured after fat load. A signi®cant relationship linked fat oxidation to plasma FFA (r 0.54, P`0.002) as well as to insulin (r 70.40, P`0.002). Conclusions: (a) The energetic cost of glucose and fat intake is the same; (2) after each load, the main source of energy corresponds to the substrate administered; (3) both plasma insulin and FFA in¯uence the substrate oxidative patterns observed after each load; (4) alimentary fat may contribute to fat oxidation by maintaining elevated plasma FFA levels.

Semen samples were collected at weekly intervals for six weeks from eight sexually mature beagles previously shown to produce normal ejaculates. Seminal plasma and sperm fractions were separated by centrifugation and the sodium, potassium, alanine and aspartate aminotransferases, acid and alkaline phosphatase concentrations in the two fractions determined. Regression analysis of the mean weekly values obtained from physical and biochemical examination of the ejaculates showed that sodium ion concentration was highest in seminal plasma. The highest levels of aminotransferases were found in sperm fractions. Those enzymes may be indices of abnormal or damaged spermatozoa. Acid and alkaline phosphatase activity was 100 times greater in seminal plasma than in sperm fractions. Phosphatase concentrations are likely to be dependent on prostate activity. Measurement of acid phosphatase in canine semen therefore may be a useful index of prostate function. The motility of the semen samples was independent of the potassium concentration in seminal plasma. However, there was some evidence of a correlation between sperm motility and the enzyme and sodium content of seminal plasma.

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