Comparative performance of the Biocentric Generic Viral Load, Roche CAP/CTM v1.5, Roche CAP/CTM v2.0 and m2000 Abbott assays for quantifying HIV-1 B and non-B strains: Underestimation of some CRF02 strains.

BACKGROUND: HIV-1 viral load testing is now recommended by the World Health Organization for every patient receiving antiretroviral therapy (ART). OBJECTIVES: The objective of this study is to evaluate the performance of commercial assays for their ability to quantify HIV-1 strains currently circulating in France. STUDY DESIGN: The performances of the Generic HIV-RNA assay from Biocentric were compared to those of the Roche CAP/CTM v1.5, Roche CAP/CTM v2.0 and Abbott m2000 RealTime HIV-1 assays. A total of 1885 HIV-1 plasma samples were tested, including 684 samples from patients included in the ANRS-Primo Cohort. RESULTS: We found a good concordance of quantification between the Roche v2.0 and the Biocentric assays, both of which were superior to the Roche v1.5 assay. We show moderate agreement between techniques; however, CRF02_AG strains and undetermined viruses were underestimated when quantified with the Roche CAP/CTM v2.0. In contrast, a comparison of the Biocentric and Abbott assay results showed strong agreement between assays, indicating that both are well suited for quantification of CRF02_AG strains. Moreover, a 2% underestimation of the B subtypes was observed with the Biocentric assay. CONCLUSIONS: These results have implications for viral load monitoring in Western Africa, where CRF02_AG strains are highly prevalent. Closer epidemiological surveillance and evaluation of commercial assays are still necessary to better evaluate the impact of the genetic evolution of circulating viruses on HIV-RNA quantification in the regions most affected by the HIV-1 epidemic.

Chronic carbon monoxide treatment attenuates development of obesity and remodels adipocytes in mice fed a high-fat diet.

OBJECTIVE: Induction of heme oxygenase-1 (HO-1) has been demonstrated to result in chronic weight loss in several rodent models of obesity. However, the specific contribution of the HO metabolite, carbon monoxide (CO) to this response remains unknown. In this study, we determined the effect of chronic low level administration of a specific CO donor on the progression of obesity and its effects on metabolism and adipocyte biology in mice fed a high-fat diet. DESIGN: Experiments were performed on C57BL/6J mice fed a high-fat diet (60%) from 4 weeks until 30 weeks of age. Mice were administered either the CO donor, carbon monoxide releasing molecules (CORM)-A1 (5 mg kg(-1), intraperitoneally every other day) or the inactive form of the drug (iCORM-A1). Body weights were measured weekly and fasted blood glucose, insulin as well as body composition were measured every 6 weeks. Food intake, O2 consumption, CO2 production, activity and body heat production were measured at 28 weeks after start of the experimental protocol. RESULTS: Chronic CORM-A1 attenuated the development of high fat induced obesity from 18 weeks until the end of the study. Chronic CORM-A1 treatment in mice fed a high-fat diet resulted in significant decreases in fasted blood glucose, insulin and body fat and increased O2 consumption and heat production as compared with mice treated with iCORM-A1. Chronic CORM-A1 treatment also resulted in a significant decrease in adipocyte size and an increase in adipocyte number and in NRF-1, PGC-1α and UCP1 protein levels in epidydmal fat. CONCLUSION: Our results demonstrate that chronic CO treatment prevents the development of high-fat diet induced obesity via stimulation of metabolism and remodeling of adipocytes.

[Epidemiology of respiratory allergy in children]. / Epidémiologie de l'allergie respiratoire de l'enfant.

Epidemiology of paediatric respiratory allergic disorders allows the approach to causal and preventive risk factors by studying groups or sub groups of children in different locations and under different conditions. This is, however, complicated by the lack of consensus on disease definitions, which renders comparisons between studies difficult. Atopy is usually defined by the presence of positive skin tests (wheal size of at least a mean diameter > or = 3 mm), by the presence of specific IgE, or by the presence of increased total IgE (> or = 100 UI/mL). Infantile asthma is not well defined, complicated by the high prevalence of bronchiolitis; one thus questions between wheezing or wheezy bronchitis. Prevalence is high: among early wheezers, two populations will be defined by the medium term evolution: transient wheezers and persistent wheezers. Risk factors for these two conditions are different. Childhood asthma may be defined by the diagnosis of asthma (specific but fairly non-sensitive), by asthmatic symptoms (wheezing, waking by an attack of shortness of breath) (sensitive but not very specific), or by the combination of symptoms and airway hyperresponsiveness. The ISAAC study has standardised a questionnaire to assess the prevalence of asthma. The preliminary results show that there are wide variations across the world. The prevalence is low in Africa and Asia, intermediate in Europe, and high in Anglo-Saxon countries. The prevalence of asthma has gradually increased over the past 20 years in developed countries. Asthma and atopy are closely associated in children. Risk factors are genetic, associated with sex and environmental factors. Among these, allergic sensitisation is associated with the degree of exposure to allergens. Westernization of way of life is associated with increased prevalence of atopy, allergic rhinitis and asthma. Atopy seems inversely correlated to certain infections. Passive smoking is clearly associated with early wheezing. This and atmospheric pollution aggravate childhood asthma. However, the inducing role of pollution on asthma is still controversial.