Impact of hepatitis B and delta virus co-infection on liver disease in Mauritania: a cross sectional study.

OBJECTIVES: Mauritania is a highly endemic region for hepatitis B (HBV) and delta (HDV) viruses. No data are available on HDV\u27s impact on the severity of liver disease in consecutive HBV-infected patients in Africa. This study evaluated the degree of liver fibrosis in a cohort of chronic HBV carriers. METHODS: Three-hundred consecutive HBV-infected Mauritanian patients were checked for HDV infection via the detection of anti-HDV antibodies (Ab) and viral RNA. HBV- vs. HBV/HDV-infected patients were compared by physical examination, biological analyses, and the APRI (aspartate aminotransferase to platelet ratio index) and FibroMeter tests for determination of liver fibrosis. RESULTS: More than 30% of the patients had anti-HDVAb. Among these, 62.2% were HDV-RNA positive. Co-infected patients were older (>8-years) than HBV-mono-infected patients. They had more liver tests abnormalities and clinical or ultrasound signs of liver fibrosis. APRI and FibroMeter scores were also significantly increased in these patients. In multivariate analysis, beyond HDVAb, male gender and HBV-VL >3.7 log IU/mL were the only markers linked to significant liver fibrosis. CONCLUSIONS: In Mauritania, HDV co-infection worsens liver disease, both clinically and biologically, as confirmed by the APRI and FibroMeter tests. These tests may be useful for the management of delta hepatitis, which is a major health problem in Mauritania

Prevalence, risk factors, and molecular epidemiology of hepatitis B and hepatitis delta virus in pregnant women and in patients in Mauritania

No recent data are available on hepatitis B virus (HBV) and hepatitis Delta virus (HDV) prevalence in Mauritania. One thousand twenty pregnant women and 946 patients visiting for routine checkups were screened for HBV and HDV infection. Demographic, epidemiological, ethnic, clinical, and biological data were recorded. HBV and HDV genotypes were determined by sequencing and phylogenetic analyses. In the pregnant women and patients cohorts, respectively, the prevalence of HBsAg (10.7% and 18.3%) and anti-HBcAb (66.3% and 76.5%) indicated high HBV endemicity. In pregnant women, exposure to HBV was significantly associated in multivariate analysis with education level, ethnicity, blood transfusion, and occupation. HDV antibodies (HDVAb) were found in 14.7% of pregnant women. In patients, HBsAg was found less frequently in females than in males. Again in multivariate analysis, exposure to HBV was significantly correlated with gender (males), and HDVAb positivity with age and gender. The HBV DNA viral load was >3 log IU/ml in only 10.1% of pregnant women and in 17.3% of patients. HDV-RNA was detectable in 21 (67.7%) of the 31 patients positive for HDVAb, and in 11 of the 16 pregnant women positive for HDVAb (68.8%). The most frequent HBV genotypes were: HBV/D, 53%; HBV/E, 35%; and HBV/A, 12%. Sub-genotyping revealed HBV/D1,/D7, and the recently described/D8. HDV genotypes were: HDV-1, 90.3% and HDV-5, 9.7%. This study confirms the high prevalence of HBV and HDV infections in Mauritania and demonstrates the high genetic diversity of HBV in this country

Rapid fucosylation of intestinal epithelium sustains host–commensal symbiosis in sickness

Systemic infection induces conserved physiological responses that include both resistance and ‘tolerance of infection’ mechanisms. Temporary anorexia associated with an infection is often beneficial, reallocating energy from food foraging towards resistance to infection or depriving pathogens of nutrients. However, it imposes a stress on intestinal commensals, as they also experience reduced substrate availability; this affects host fitness owing to the loss of caloric intake and colonization resistance (protection from additional infections). We hypothesized that the host might utilize internal resources to support the gut microbiota during the acute phase of the disease. Here we show that systemic exposure to Toll-like receptor (TLR) ligands causes rapid α(1,2)-fucosylation of small intestine epithelial cells (IECs) in mice, which requires the sensing of TLR agonists, as well as the production of interleukin (IL)-23 by dendritic cells, activation of innate lymphoid cells and expression of fucosyltransferase 2 (Fut2) by IL-22-stimulated IECs. Fucosylated proteins are shed into the lumen and fucose is liberated and metabolized by the gut microbiota, as shown by reporter bacteria and community-wide analysis of microbial gene expression. Fucose affects the expression of microbial metabolic pathways and reduces the expression of bacterial virulence genes. It also improves host tolerance of the mild pathogen Citrobacter rodentium. Thus, rapid IEC fucosylation appears to be a protective mechanism that utilizes the host’s resources to maintain host–microbial interactions during pathogen-induced stress

Long-term durability of CFRP under fatigue loading for marine applications

Composite propellers are a major new development in the marine transport industry. The use of composite materials in seawater turbines is also of great interest to the marine renewable energy industry. Those systems present similarities being both constantly immersed in seawater, under fatigue loadings, of large dimensions, and they are often designed using Carbon Fibre Reinforced Polymer (CFRP). Previous studies have shown sensitivity of some composite materials to the seawater environment mainly in the quasi-static loading domain. However, investigations now need to be performed on the behaviour of CFRP under seawater environment and fatigue loadings. In this study, CFRP samples were aged in natural seawater until saturation, in order to investigate the influence of water absorption on the fatigue properties of the material. Results showed a small decrease in fatigue lifetime under tension but a more significant drop for sample subjected to four point flexural fatigue

Long-term durability of CFRP under fatigue loading for marine applications

Composite propellers are a major new development in the marine transport industry. The use of composite materials in seawater turbines is also of great interest to the marine renewable energy industry. Those systems present similarities being both constantly immersed in seawater, under fatigue loadings, of large dimensions, and they are often designed using Carbon Fibre Reinforced Polymer (CFRP). Previous studies have shown sensitivity of some composite materials to the seawater environment mainly in the quasi-static loading domain. However, investigations now need to be performed on the behaviour of CFRP under seawater environment and fatigue loadings. In this study, CFRP samples were aged in natural seawater until saturation, in order to investigate the influence of water absorption on the fatigue properties of the material. Results showed a small decrease in fatigue lifetime under tension but a more significant drop for sample subjected to four point flexural fatigue

From face-to-face to mobile Internet: replicate the French ESS questionnaire on the ELIPSS panel

The European Social Survey (ESS) is an academically driven cross-national survey conducted every two years across Europe, in which France has participated since the first round in 2002. The ESS measures the attitudes, beliefs and behaviour patterns of various populations in more than thirty countries. One of its main goals aims to track stability and changes in the social structure of European societies and to provide analysis elements on how Europe’s social, political and moral fabric is changing. In the ESS, data are collected via face-to-face interviews. In France, the fieldwork of the 7th round led to a survey replication on the pilot of the Elipss panel (Longitudinal Internet Studies for Social Sciences). Elipss is a probability based online panel that is representative of the French population aged 18-75. Panel members are randomly selected by The French National Institute of Statistics and Economic Studies (INSEE) and equipped with a touch-screen tablet and a 3G Internet subscription. Every month they are asked to answer a 30 minutes self-administered questionnaire proposed by researchers and selected by a scientific and technical committee. The Center of Socio-Political Data of Sciences Po coordinates the ESS fieldwork for France and conducts the Elipss panel. Consecutively we developed an expertise on the methodology and the process of each mode. The face-to-face fieldwork was carried out from November 2014 to February 2015. To replicate it on the Elipss panel, we used a slot between December 2014 and January 2015. The administration of the first part of the ESS core questionnaire on the Elipss panel gave an opportunity to wonder how the different strategies for collecting data may impact the response behaviour. Knowing that differences are already emerging in the specificities of these two protocols, the questionnaire needed some adjustments that we must consider in such a comparison. Indeed, for its replication in a self-administered mode on a mobile device we had to adapt the design of some questions, and it could have impacted the answer situation. The difference in the structure of the sample should be taken into account to explain the observed differences. The length of the questionnaire, the format of the answer categories, the presence or absence of an interviewer, the survey experience of Elipss panel members could also account for differences in response behaviour. Focusing on type and design of questions, we will pay special attention to the social desirability effect often pointed out in face-to-face surveys. This paper will highlight the specificities of the two survey designs (face-to-face vs self-administered online questionnaire) in order to discuss the scope of such a comparison. Finally, we will compare the answers according to whether the data is collected by interviewers or self-administered on mobile device