Epidemiological, biological and histological characterization of patients with indeterminate third-generation recombinant immunoblot assay antibody results for hepatitis C virus.

We studied the epidemiological, laboratory and histological characteristics of a group of patients with positive antibodies against hepatitis C virus (HCV) as determined by third-generation enzyme-linked immunosorbent assay (ELISA), and with indeterminate HCV antibody positivity as established by third-generation recombinant immunoblot assay (RIBA-3). The results obtained were compared with those recorded in a group of RIBA-3-positive patients. Both groups correspond to blood donors in whom the prevalence of hepatitis C is low. There were no statistically significant intergroup differences in mean age, or in the presence of infection risk factors. RNA positivity was much more frequent in the RIBA-positive group (71%vs 10%; P < 0.05), as was transaminase elevation during the 3 years of follow-up (54%vs 13%; P < 0.05). In 46% of the RIBA-indeterminate patients the liver biopsy proved normal, or only liver steatosis or minimal changes were detected, while 33% had persistent chronic hepatitis, and 21% showed active chronic hepatitis. A mean Knodell index score of 2.28 was recorded; 50% of the subjects showed no fibrosis, 46% grade 1 fibrosis (fibrous portal expansion), 4% grade 2 fibrosis (bridging fibrosis), and none grade 3 fibrosis (liver cirrhosis). In the RIBA-positive group, a greater percentage of patients had active chronic hepatitis, a greater Knodell index, and increased-grade fibrosis. It can be concluded that the RIBA-3-indeterminate group is epidemiologically similar to the RIBA-3-positive series, although with a lesser prevalence of laboratory test alterations, a lower viral replication index, and more likely to have benign disease - particularly in subjects without viral replication.

Massive obesity in adolescents: dietary interventions and behaviours associated with weight regain at 2 y follow-up.

OBJECTIVE: To compare the influence of weight-reducing diets containing different amounts of protein and CHO on body composition in obese adolescents and to examine dietary and physical activity behaviours during follow-up. DESIGN: Prospective randomised study comparing two weight-reducing diets with the same energy (1750 kcal) and fat (31%) content, but different protein and carbohydrate contents: PROT- (15% protein, 54% CHO) vs PROT+ (19% protein, 50% CHO). PATIENTS: Massively obese 11- to 16-year-old children (32 boys and 89 girls). SETTING: A 9-month treatment in a medical centre (boarding school) plus a 2-y follow-up in free-living patients examined at home 1 and 2 y after treatment. MEASUREMENTS: Anthropometry, bioelectrical impedance, nutritional intakes and physical activity. RESULTS: Of the 121 eligible children (61 in PROT- and 60 in PROT+), 82% completed the trial until the end of weight loss treatment and 60% were followed 2 y after treatment. Body mass index (BMI) value at inclusion was 36.3 kg/m(2) or 4.3 z-scores (2.9-5.9). BMI z-score decreased to 1.7 at the end of treatment and went back to 2.8 (0.8-6.1) 2 y after treatment. This corresponded to a weight loss of 30.3 kg and weight regain of 21.3 kg. After treatment, energy intake increased and physical activity decreased. The contribution of energy ingested at breakfast decreased while snacking increased. For all measurements, no dietary group differences existed at baseline or at any time during the intervention and follow-up. CONCLUSION: A higher protein content of the diet did not confer any benefit in the treatment of childhood obesity. Substantial weight loss was obtained with a moderately energy-restricted diet and normal fat content. After weight loss, mean weight increased in spite of moderate energy intake, together with a drift towards obesity-associated behavioural patterns. The causes of the inability to adopt normal weight subjects' behaviour permanently deserve to be investigated further.

The impact of environment on ontogenesis variations in Ruggieria and Chrysocythere (Ostracoda).

The ontogenetic development of Ruggieria lekkii, Ruggieria triangulata, Ruggieria martinsoni and Chrysocythere ornata (Ostracoda) was investigated on two different continental shelves (Congo and Senegal). For one species, the ontogenetic trajectories obtained through length and height of valves differed considerably in distinct areas. In the first case, trajectories showing well-separated development stages and slight intraspecific variability in length and height were seen. In the second, trajectories showing valves which are difficult to relate to one stage or another and a high intraspecific variability were noted. In the latter, the uncertainties in the determination of the development stages were resolved by using a statistical method. Furthermore, this allowed for the comparison of the variations in ontogenesis (augmentation or reduction in the development), in relation to abiotic (detrital supply and upwelling processes) and biotic ecological factors (faunal density and interspecific competition). Comparisons were also made with ornamental variations observed on Chrysocythere ornata, which are directly linked with bioprecipitation (environmental) conditions. This comparison highlights the role played by abiotic and trophic factors on the developmental variations of ostracods in some continental shelves areas. This work shows that ontogenetic variations depend either on biotic or abiotic factors. They can act in different ways on distinct species and one can be predominant in a particular biota. Once the architectural characters have appeared, their variations no more depend on ontogenetic development. The study of ontogenesis reveals the adaptation capacities of one species in an environment with variable conditions.