Return of naturally sourced Pb to Atlantic surface waters

Anthropogenic emissions completely overwhelmed natural marine lead (Pb) sources during the past century, predominantly due to leaded petrol usage. Here, based on Pb isotope measurements, we reassess the importance of natural and anthropogenic Pb sources to the tropical North Atlantic following the nearly complete global cessation of leaded petrol use. Significant proportions of up to 30-50% of natural Pb, derived from mineral dust, are observed in Atlantic surface waters, reflecting the success of the global effort to reduce anthropogenic Pb emissions. The observation of mineral dust derived Pb in surface waters is governed by the elevated atmospheric mineral dust concentration of the North African dust plume and the dominance of dry deposition for the atmospheric aerosol flux to surface waters. Given these specific regional conditions, emissions from anthropogenic activities will remain the dominant global marine Pb source, even in the absence of leaded petrol combustion

Dasabuvir: a new direct antiviral agent for the treatment of hepatitis C

Introduction: Treatment of hepatitis C virus (HCV) infection with direct-acting antivirals (DAAs) has revolutionized the care of infected patients. Among these novel compounds are non-nucleoside analogs, which bind viral RNA-dependent RNA polymerase resulting in a conformational change inhibiting RNA synthesis. Areas covered: Efficacy and tolerability of treatment regimens containing the non-nucleoside analog polymerase inhibitor dasabuvir (ABT-333). Expert opinion: Dasabuvir-containing regimens achieve high rates of sustained virologic response in HCV genotype 1a and 1b-infected patients when combined with other DAAs, namely paritaprevir (ABT-450), ritonavir and ombitasvir (ABT-267). In the populations studied, dasabuvir seems to be well tolerated and safe. The major limitations of this novel drug are its genotype-restricted activity, the necessity to include ribavirin for HCV genotype 1a and the emergence of resistance if not combined with other DDAs