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Yeasts Saccharomyces cerevisiae, like other microbes in nature, respond to the unavailability of nutrients with entrance in quiescent/G0 state. These cells exist in non-dividing, latent form by maintaining the cellular metabolism at a low level but still able to sense and adapt to environmental stresses. Their quiescent status characteristics are likely close to those of tissues and organs in mammals and humans. This fact makes them an appropriate model system for investigation of the basic mechanisms underlying the toxicity of different chemical compounds. In this study, the toxic effect of H2O2 and menadione on quiescent S. cerevisiae cells was evaluated through the analysis of RNA polymerases transcription profile and ribosomal RNA content. Distinct RNA polymerases subunits were expressed in G0 yeast cells after short exposure to 0.1 mmol/L menadione and 5 mmol/L hydrogen peroxide. Significant transcription repression of RNA polymerases genes was observed as a response to menadione. Both stress agents induced changes in the 25S and 18S rRNA profile in quiescent and proliferating yeast cells. These results strongly suggest that the toxicological response of eukaryotic cells involves rapid alterations in RNA polymerases gene expression and changes in RNA transcriptome profiles, and depends on the specific mechanism of toxic action. [ABSTRACT FROM AUTHOR]

The increasing antibiotic resistance among pathogenic bacteria is a challenge that drives the development of new antibacterial substances. Marine inhabitants are excellent sources of antimicrobial proteins and considered as promising candidates for the treatment of microbial infections. In the present study, we obtained haemocyanin from Eriphia verrucosa and studied its potential to suppress the growth of some pathogenic bacteria and yeasts. The putative antibacterial molecules were isolated from the haemolymph by chromatography appropriate for producing the native haemocyanin (EvH) and its five structural units (SUs). The results showed that EvH had no antimicrobial activity unlike its glycosylated SUs. All haemocyanin SUs exhibited differential antibacterial activity depending on their grade of glycosylation. The strongest antimicrobial activity of SU1 (with highest carbohydrate content) was against Escherichia coli and Bacillus subtilis. The least glycosylated SU3 and SU4 exhibited the lowest antimicrobial activity against all strains. The fraction SU1 has the potential to be applied as a substitute for some commonly used antibiotics. It was demonstrated that the grade of haemocyanin glycosylation plays an important role in its functional antibacterial properties. [ABSTRACT FROM AUTHOR]

We carried out a genome-wide association study of schizophrenia (479 cases, 2,937 controls) and tested loci with P < 10−5 in up to 16,726 additional subjects. Of 12 loci followed up, 3 had strong independent support (P < 5 × 10−4), and the overall pattern of replication was unlikely to occur by chance (P = 9 × 10−8). Meta-analysis provided strongest evidence for association around ZNF804A (P = 1.61 × 10−7) and this strengthened when the affected phenotype included bipolar disorder (P = 9.96 × 10−9). [ABSTRACT FROM AUTHOR]