Cadmium (Cd) and its compounds were classified as "carcinogenic to humans (Group 1)" by IARC in 1993. The observation of an increased number of lung cancers in a U.S. cohort of cadmium-exposed workers and the finding of tumors in animals exposed to various cadmium compounds apparently played an important role in this assessment. Since this evaluation, several cohorts of cadmium exposed workers have been updated and some additional data regarding environmental exposure to cadmium and cancer risk have been published. The main purpose of this systematic review was to examine whether inclusion of the studies that were not available for the 1993 evaluation might change the overall assessment of the carcinogenic potential of cadmium compounds. A second objective was to examine whether the recent studies are qualitatively better than the older ones and whether they should receive more weight in this assessment. A third issue was to investigate whether a competing effect between nonmalignant respiratory disease (NMRD) and lung cancer may have affected the results for lung cancer in occupationally exposed cohorts. Overall, considering the results of the most recent studies does not suggest that the effect of cadmium on lung cancer increases with improvement of the study design but points to a lower relative risk in the groups exposed to cadmium in the absence of arsenic and nickel. No evidence was found to support the hypothesis that NMRD represents a competing cause of death reducing the mortality from lung cancer. The association between cadmium exposure and prostate cancer was not confirmed in the latest available updates. Studies in environmentally exposed populations do not indicate an increased relative risk of cancer.

Higher-order structures that originate from the specific and reversible DNA-directed self-assembly of microscopic building blocks hold great promise for future technologies. Here, we functionalized biotinylated soft colloid oil-in-water emulsion droplets with biotinylated single-stranded DNA oligonucleotides using streptavidin as an intermediary linker. We show the components of this modular linking system to be stable and to induce sequencespecific aggregation of binary mixtures of emulsion droplets. Three length scales were thereby involved: nanoscale DNA base pairing linking microscopic building blocks resulted in macroscopic aggregates visible to the naked eye. The aggregation process was reversible by changing the temperature and electrolyte concentration and by the addition of competing oligonucleotides. The system was reset and reused by subsequent refunctionalization of the emulsion droplets. DNA-directed self-assembly of oil-in-water emulsion droplets, therefore, offers a solid basis for programmable and recyclable soft materials that undergo structural rearrangements on demand and that range in application from information technology to medicine.C omplex higher-order structures that spontaneously arise from the specific and reversible self-assembly of simple building blocks hold great promise to become the foundation of tomorrow's technology (1). In the context of DNA-directed self-assembly of hard colloids and artificial vesicles, linear DNA oligonucleotides were shown to be adhesive elements that allowed the self-assembly process not only to be specific but also to be reversible by a variety of external stimuli such as temperature (2-4), changes in the electrolyte concentration (4, 5), addition of competing oligonucleotides (6), and exploitation of the secondary structure of DNA oligonucleotides (7).Oil-in-water (o/w) emulsion droplets (EDs) offer a robust, configurable, and recyclable soft-colloid system with interesting properties for the fabrication of new delivery systems and advanced synthetic materials with adaptable properties (8). By exploiting the well-characterized ligand-receptor pair biotin-streptavidin, EDs were immobilized on glass surfaces (9) and actively transported along microtubules (10). In the context of self-assembly, both polymer-mediated (11-13) and biotin-streptavidin-mediated aggregation of EDs was shown (14). Despite the advantages a combination of EDs as building blocks and DNA oligonucleotides as linking agent offers, a protocol for DNA-directed self-assembly of EDs is currently missing.To close this gap, here we prepared an o/w emulsion composed of heavier-than-water diethyl phthalate (DEP) dispersed in an aqueous medium, stabilized by phospholipids, and functionalized with single-stranded DNA (ssDNA) oligonucleotides. Palmitoyloleoyl phosphatidylcholine (POPC) and distearoylphosphatidyl ethanolamine (DSPE) in a 9:1 molar ratio were used to stabilize the EDs. The DSPE was grafted with flexible poly(ethylene glycol) (PEG) tethers with a molecular weight of 2,000 (DSPE-PEG...

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Hepatitis E virus (HEV) is responsible for many enterically transmitted viral hepatitides around the world. It is currently one of the waterborne diseases of global concern. In industrialized countries, HEV appears to be more common than previously thought, even if it is rarely virulent. In Switzerland, seroprevalence studies revealed that HEV is endemic, but no information was available on its environmental spread. The aim of this study was to investigate -using qPCR- the occurrence and concentration of HEV and three other viruses (norovirus genogroup II, human adenovirus-40 and porcine adenovirus) in influents and effluents of 31 wastewater treatment plants (WWTPs) in Switzerland. Low concentrations of HEV were detected in 40 out of 124 WWTP influent samples, showing that HEV is commonly present in this region. The frequency of HEV occurrence was higher in summer than in winter. No HEV was detected in WWTP effluent samples, which indicates a low risk of environmental contamination. HEV occurrence and concentrations were lower than those of norovirus and adenovirus. The autochthonous HEV genotype 3 was found in all positive samples, but a strain of the non-endemic and highly pathogenic HEV genotype I was isolated in one sample, highlighting the possibility of environmental circulation of this genotype. A porcine fecal marker (porcine adenovirus) was not detected in HEV positive samples, indicating that swine are not the direct source of HEV present in wastewater. Further investigations will be necessary to determine the reservoirs and the routes of dissemination of HEV.