Determination of toxic elements (mercury, cadmium, lead, tin and arsenic) in fish and shellfish samples. Risk assessment for the consumers

The authors would gratefully like to acknowledge the financial support given by Fondo de Investigaciones Sanitarias (reference PI10/00527). They are also grateful to the Spanish Ministry of Education, Culture and Sport for awarding Pablo Olmedo a FPU predoctoral fellowship (reference AP2009-0534) to achieve his PhD degree in the context of this research project.Although fish intake has potential health benefits, the presence of metal contamination in seafood has raised public health concerns. In this study, levels of mercury, cadmium, lead, tin and arsenic have been determined in fresh, canned and frozen fish and shellfish products and compared with the maximum levels currently in force. In a further step, potential human health risks for the consumers were assessed. A total of 485 samples of the 43 most frequently consumed fish and shellfish species in Andalusia (Southern Spain) were analyzed for their toxic elements content. High mercury concentrations were found in some predatory species (blue shark, cat shark, swordfish and tuna), although they were below the regulatory maximum levels. In the case of cadmium, bivalve mollusks such as canned clams and mussels presented higher concentrations than fish, but almost none of the samples analyzed exceeded the maximum levels. Lead concentrations were almost negligible with the exception of frozen common sole, which showed median levels above the legal limit. Tin levels in canned products were far below the maximum regulatory limit, indicating that no significant tin was transferred from the can. Arsenic concentrations were higher in crustaceans such as fresh and frozen shrimps. The risk assessment performed indicated that fish and shellfish products were safe for the average consumer, although a potential risk cannot be dismissed for regular or excessive consumers of particular fish species, such as tuna, swordfish, blue shark and cat shark (for mercury) and common sole (for lead).Instituto de Salud Carlos III PI10/00527Spanish Ministry of Education, Culture and Sport AP2009-053

Fast determination of lipophilicity by HPLC

A rapid method for the determination of lipophilicity by reversed-phase high-performance liquid chromatography is presented with a study of a set of 29 molecules representing various functional groups. The use of a short column packed with a polar-embedded phase and octanol-saturated water as eluent for direct measurement of log k(w) is described. Extrapolation for log k(w) measurements can be avoided for solutes having log P in the octanol/water system of less than 3.2. The gain in terms of productivity and simplicity of analysis over the direct measurement shows the usefulness of this method for industrial applications. Good correlations between log P values found in the literature and measured log k(w) values were obtaine

Histo-blood group antigen-binding specificities of human rotaviruses are associated with gastroenteritis but not with in vitro infection

Human strains of rotavirus A (RVAs) recognize fucosylated glycans belonging to histo-blood group antigens (HBGAs) through their spike protein VP8*. Lack of these ligands due to genetic polymorphisms is associated with resistance to gastroenteritis caused by P[8] genotype RVAs. With the aim to delineate the contribution of HBGAs in the process, we analyzed the glycan specificity of VP8* proteins from various P genotypes. Binding to saliva of VP8* from P[8] and P[4] genotypes required expression of both FUT2 and FUT3 enzymes, whilst binding of VP8* from the P[14] genotype required FUT2 and A enzymes. We further defined a glycan motif, GlcNAc beta 3Gal beta 4GlcNAc, recognized by P[6] clinical strains. Conversion into Lewis antigens by the FUT3 enzyme impaired recognition, explaining their lower binding to saliva of Lewis positive phenotype. In addition, the presence of neutralizing antibodies was associated with the presence of the FUT2 wild type allele in sera from young healthy adults. Nonetheless, in vitro infection of transformed cell lines was independent of HBGAs expression, indicating that HBGAs are not human RV receptors. The match between results from saliva-based binding assays and the epidemiological data indicates that the polymorphism of human HBGAs controls susceptibility to RVAs, although the exact mechanism remains unclear.Funding Agencies|Agence Nationale de la Recherche (France): GASTROVIM; Region des Pays de la Loire (France): ARMINA; Merieux Research Grant GOMMs; Russian Science Foundation [14-5-00131]; Swedish Research Council [320301]</p