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Transport measurements were performed on the organic layered compound \aI3 under hydrostatic pressure. The carrier types, densities and mobilities are determined from the magneto-conductance of \aI3 . While evidence of high-mobility massless Dirac carriers has already been given, we report here, their coexistence with low-mobility massive holes. This coexistence seems robust as it has been found up to the highest studied pressure. Our results are in agreement with recent DFT calculations of the band structure of this system under hydrostatic pressure. A comparison with graphene Dirac carriers has also been done., Comment: 5 pages 5 figures

We report the magnetic field-amplitude and field-angle dependence of the superconducting onset temperature Tc_onset of the organic superconductor (TMTSF)2ClO4 in magnetic fields H accurately aligned to the conductive ab' plane. We revealed that the rapid increase of the onset fields at low temperatures occurs both for H // b' and H // a, irrespective of the carrier confinement. Moreover, in the vicinity of the Pauli limiting field, we report a shift of a principal axis of the in-plane field-angle dependence of Tc_onset away from the b' axis. This feature may be related to an occurrence of Fulde-Ferrell-Larkin-Ovchinnikov phases., Comment: 4 pages, 4 figures

International audience; To determine the prevalence of hepatitis C virus (HCV) infection and genotype distribution in a rural isolated area of Central Africa, plasma of 409 Bantous (mean age, 32 years; range, 2-78 years) living in a remote village of the rain forest of Southern Cameroon was screened for anti-HCV antibodies. HCV seropositive samples were also subjected to qualitative detection of viral RNA. HCV antibodies were detected in 70 (17.1%) individuals, 48 (68.8%) of whom had detectable viremia. The seroprevalence did not differ by gender (P = 0.37), but increased significantly with age (P < 0.05), with a strong increase in the oldest age groups. Indeed, nearly one-half (48%) of the adults >50 years old were HCV seropositive. The characterization of the viral genotypes indicated that most of the HCV strains were of genotype 4 (76%), while genotype 2 (16%), and 1 (8%) were marginally represented. The results suggest a cohort effect with an old, possibly iatrogenic, group exposure rather than a continuous exposure. A more in-depth population-based epidemiological study is needed to address this issue further.

Percutaneous transluminal coronary angioplasty (PTCA) induces deep arterial wall injury and transient ischaemia. The aim of this study was to demonstrate that PTCA could result in priming or activation of the neutrophils and the complement system.Blood was drawn from the coronary sinus before and immediately after PTCA in 7 patients and before and immediately after coronary angiography in 7 patients (to ensure that the changes observed after PTCA were not solely related to the angiographic procedure). Neutrophil priming was assessed ex vivo by whole blood chemiluminescence stimulated in vitro by formyl-methionyl-leucyl-phenylalanine, phorbol myristate and opsonized zymosan. Neutrophil activation was assessed by measurement of plasma lactoferrin.Whole blood chemiluminescence increased after PTCA, regardless of the stimulus used, while it did not after arteriography. After PTCA, lactoferrin increased 2-fold (p0.02) whereas after arteriography a non-significant increase was observed. Neutrophil count and adherence properties were not modified by either PTCA or arteriography. Total haemolytic complement (CH50), C3, C4 and B factor decreased slightly (7 to 16%) after both PTCA and arteriography.Early after PTCA, the neutrophil oxidative response, assessed by stimulated whole blood chemiluminescence, increased, suggesting a "priming" effect of PTCA on neutrophils. In addition, plasma lactoferrin levels increased, indicating neutrophil activation. Finally, there was a mild global activation of the complement system, most likely related to the contrast agent, and which may play a role in the "priming" process. Neutrophil priming and activation may participate in several phenomena occurring after angioplasty such as enhanced vasoconstriction and post-ischaemic myocardial dysfunction. In addition, it may participate in triggering local inflammatory processes.