An Accurate Definition of the Status of Inactive Hepatitis B Virus Carrier by a Combination of Biomarkers (FibroTest-ActiTest) and Viral Load

BACKGROUND: The combination of transaminases (ALT), biopsy, HBeAg and viral load have classically defined the inactive status of carriers of chronic hepatitis B. The use of FibroTest (FT) and ActiTest (AT), biomarkers of fibrosis and necroinflammatory activity, has been previously validated as alternatives to biopsy. We compared the 4-year prognostic value of combining FT-AT and viral load for a better definition of the inactive carrier status. METHODS AND FINDINGS: 1,300 consecutive CHB patients who had been prospectively followed since 2001 were pre-included. The main endpoint was the absence of liver-related complications, transplantation or death. We used the manufacturers' definitions of normal FT (< = 0.27), normal AT (< = 0.29) and 3 standard classes for viral load. The adjustment factors were age, sex, HBeAg, ethnic origin, alcohol consumption, HIV-Delta-HCV co-infections and treatment. RESULTS: 1,074 patients with baseline FT-AT and viral load were included: 41 years old, 47% African, 27% Asian, 26% Caucasian. At 4 years follow-up, 50 complications occurred (survival without complications 93.4%), 36 deaths occurred (survival 95.0%), including 27 related to HBV (survival 96.1%). The prognostic value of FT was higher than those of viral load or ALT when compared using area under the ROC curves [0.89 (95%CI 0.84-0.93) vs 0.64 (0.55-0.71) vs 0.53 (0.46-0.60) all P<0.001], survival curves and multivariate Cox model [regression coefficient 5.2 (3.5-6.9; P<0.001) vs 0.53 (0.15-0.92; P = 0.007) vs -0.001 (-0.003-0.000;P = 0.052)] respectively. A new definition of inactive carriers was proposed with an algorithm combining "zero" scores for FT-AT (F0 and A0) and viral load classes. This new algorithm provides a 100% negative predictive value for the prediction of liver related complications or death. Among the 275 patients with the classic definition of inactive carrier, 62 (23%) had fibrosis presumed with FT, and 3 died or had complications at 4 year. CONCLUSION: In patients with chronic hepatitis B, a combination of FibroTest-ActiTest and viral load testing accurately defined the prognosis and the inactive carrier status

Essais biologiques pour l'évaluation de la toxicité chronique des rejets

Based on an investigation conducted near laboratories, the authors suggest a series of tests on algae, micro-shellfish and fish susceptible of being rapidly used in France by water agencies to measure waste chronical toxicity. The suggested methods are justified depending on information they bring about long-term impact risks of effluents, their ecological relevance and their performance: rapidity, feasability, sensitivity, repeatability. The comparison of toxicity results obtained in Canada on different types of effluents with the suggested tests, demonstrates the complementarity of these methods. / A partir d'une enquête auprès de laboratoires, les auteurs proposent une batterie d'essais sur algues, microcrustacés et poissons susceptibles d'être rapidement utilisés en France par les Agences de l'eau, pour la mesure de la toxicité chronique des rejets. Les méthodes proposées sont justifiées en fonction des informations qu'elles apportent sur les risques d'impacts à long terme des effluents, de leur pertinence écologique et de leur performance : rapidité, faisabilité, sensibilité, reproductibilité. La comparaison de résultats de toxicité obtenus au Canada sur divers types d'effluents, à l'aide des essais proposés, permet de mettre en évidence la complémentarité de ces méthodes

Transferability of Lipase Titrimetric Assays: Deductions from an Interlaboratory Study

Peer Reviewe

Magnetotactic bacteria as a new model for P sequestration in the ferruginous Lake Pavin

International audienceThe role of microorganisms in the geochemical cycle of P has received great interest in the context of enhanced biological phosphorus removal and phosphorite formation. Here, we combine scanning and transmission electron microscopies, confocal laser scanning microscopy and synchrotron-based x-ray microfluorescence to analyse the distribution of P at the oxic-anoxic interface in the water column of the ferruginous Lake Pavin. We show that magnetotactic bacteria of the Magnetococca-ceae family strongly accumulate polyphosphates and appear as P hotspots in the particulate fraction at this depth. This high accumulation may be characteristic of this family and may also relate to the chemical conditions prevailing in the lake. As a result, these magneto-tactic cocci can be considered as new models playing a potentially important role in the P geochemical cycle, similar to sulphide oxidising bacteria such as Thiomargarita and Beggiatoa but thriving in a ferruginous, poorly sulphidic environment

Magnetotactic bacteria as a new model for P sequestration in the ferruginous Lake Pavin

International audienceThe role of microorganisms in the geochemical cycle of P has received great interest in the context of enhanced biological phosphorus removal and phosphorite formation. Here, we combine scanning and transmission electron microscopies, confocal laser scanning microscopy and synchrotron-based x-ray microfluorescence to analyse the distribution of P at the oxic-anoxic interface in the water column of the ferruginous Lake Pavin. We show that magnetotactic bacteria of the Magnetococca-ceae family strongly accumulate polyphosphates and appear as P hotspots in the particulate fraction at this depth. This high accumulation may be characteristic of this family and may also relate to the chemical conditions prevailing in the lake. As a result, these magneto-tactic cocci can be considered as new models playing a potentially important role in the P geochemical cycle, similar to sulphide oxidising bacteria such as Thiomargarita and Beggiatoa but thriving in a ferruginous, poorly sulphidic environment

Transferability of Lipase Titrimetric Assays: Deductions from an Interlaboratory Study

Peer Reviewe