Carbohydrate-derived iminium salt organocatalysts for the asymmetric epoxidation of alkenes

A new family of carbohydrate-based dihydroisoquinolinium salts has been prepared and tested for potential as asymmetric catalysts for the epoxidation of unfunctionalized alkene substrates, providing up to 57% ee in the product epoxides

New biphenyl iminium salt catalysts for highly enantioselective asymmetric epoxidation: role of additional substitution and dihedral angle

New biaryl iminium salt catalysts for enantioselective alkene epoxidation containing additional substitution in the heterocyclic ring are reported. The effects upon conformation and enantioselectivity of this additional substitution, and the influence of dihedral angle in these systems, has been investigated using a synthetic approach supported by density functional theory. Enantioselectivities of up to 97% ee were observed

Effectiveness of the 23-valent pneumococcal polysaccharide vaccine against Invasive Pneumococcal Disease incidence in European adults aged 65 years and above : results of SpIDnet/I-MOVE+ multicentre study (2012-2016)

Background and Aims: We measured the effectiveness of 23-valent pneumococcal polysaccharidic vaccine(PPV23) against invasive pneumococcal disease (IPD) in 65+ year-olds, pooling surveillance data from seven European sites. PPV23 vaccination is recommended in all sites (8-69% uptake) and PCV13 in high risk groups in two sites (<5%uptake). Methods: We compared the vaccination status of IPD cases caused byPPV23 serotypes (cases) to that of nonPPV23 IPD (controls) notified between2012 and 2016. We defined PPV23 vaccination as at least one dose. PPV23 pooled effectiveness was calculated as (1 –odds ratio of vaccination)*100, adjusted for site, age, sex, underlying conditions and year. We stratified PPV23effectiveness by time since last dose of vaccine: <2, 2-4, 5-9 and 10+years. Results: We included 2011 cases and 878 controls. Compared to controls,cases were younger (p=0.001), less likely to have an underlying condition(p=0.025), more likely to be admitted for intensive care (p=0.038) and to have pneumonia (p=0.005). PPV23 effectiveness was 24% (95%CI: 4; 41) against PPV23-serotypes.By serotype, PPV23 effectiveness ranged between -2% (95%CI: -48; 30) against serotype 3 (n=687) and 55% (95%CI: 15; 76) against serotype 9N IPD (n=540). By years since vaccination, PPV23 effectiveness was 43% (95%CI: 3-66) and 15%(95%CI: -25; 43) for <2 years and 10+ years, respectively. Conclusion: Our findings suggest a low PPV23 effectiveness against IPD caused by PPV23serotypes in the elderly, varying by serotype, and higher in the first two years after vaccination. Despite low effectiveness, PPV23 in the elderly may prevent at least 25% of cases among vaccinated

Meningococcal Factor H Binding Proteins in Epidemic Strains from Africa: Implications for Vaccine Development

Epidemics of meningococcal meningitis are common in sub-Saharan Africa. Most are caused by encapsulated serogroup A strains, which rarely cause disease in industrialized countries. A serogroup A polysaccharide protein conjugate vaccine recently was introduced in some countries in sub-Saharan Africa. The antibodies induced, however, may allow replacement of serogroup A strains with serogroup W-135 or X strains, which also cause epidemics in this region. Protein antigens, such as factor H binding protein (fHbp), are promising for prevention of meningococcal serogroup B disease. These proteins also are present in strains with other capsular serogroups. Here we report investigation of the potential of fHbp vaccines for prevention of disease caused by serogroup A, W-135 and X strains from Africa. Four fHbp amino acid sequence variants accounted for 81% of the 106 African isolates studied. While there was little cross-protective activity by antibodies elicited in mice by recombinant fHbp vaccines from each of the four sequence variants, a prototype native outer membrane vesicle (NOMV) vaccine from a mutant with over-expressed fHbp elicited antibodies with broad protective activity. A NOMV vaccine has the potential to supplement coverage by the group A conjugate vaccine and help prevent emergence of disease caused by non-serogroup A strains

Les micromammifères du Quaternaire d'Europe occidentale

National audienceLes micromammifères du Quaternaire d'Europe occidental

Les micromammifères du Quaternaire d'Europe occidentale

National audienceLes micromammifères du Quaternaire d'Europe occidental

Les faunes de rongeurs quaternaires de la grotte du Cavillon

Les faunes de rongeurs quaternaires de la grotte du Cavillo