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Copy number variants (CNVs) conferring risk of schizophrenia present incomplete penetrance, suggesting the existence of second genetic hits. Identification of second hits may help to find genes with rare variants of susceptibility to schizophrenia. The aim of this work was to search for second hits of moderate/high risk in schizophrenia carriers of risk CNVs and resequencing of the relevant genes in additional samples. To this end, ten patients with risk CNVs at cytobands 15q11.2, 15q11.2-13.1, 16p11.2, or 16p13.11, were subjected to whole-exome sequencing. Rare single nucleotide variants, defined as those absent from main public databases, were classified according to bioinformatic prediction of pathogenicity by CADD scores. The average number of rare predicted pathogenic variants per sample was 13.6 (SD 2.01). Two genes, BFAR and SYNJ1, presented rare predicted pathogenic variants in more than one sample. Follow-up resequencing of these genes in 432 additional cases and 432 controls identified a significant excess of rare predicted pathogenic variants in case samples at SYNJ1. Taking into account its function in clathrin-mediated synaptic vesicle endocytosis at presynaptic terminals, our results suggest an impairment of this process in schizophrenia. [ABSTRACT FROM AUTHOR]

Even though the suitability of macrophytes to act as a carbon source to food webs has been questioned by some studies, some others indicate that macrophyte-derived carbon may play an important role in the trophic transfer of organic matter in the food web of shallow lakes. To evaluate the importance of macrophytes to food webs, we collected primary producers-macrophytes and periphyton-and consumers from 19 South American shallow lakes and analyzed their carbon stable isotopes composition (δC). Despite the diversity of inorganic carbon sources available in our study lakes, the macrophytes' δC signatures showed a clear bimodal distribution: C-depleted and C-enriched, averaging at −27.2 and −13.5‰, respectively. We argue that the use of either CO or HCO by the macrophytes largely caused the bimodal pattern in δC signals. The contribution of carbon from macrophytes to the lake's food webs was not straightforward in most of the lakes because the macrophytes' isotopic composition was quite similar to the isotopic composition of periphyton, phytoplankton, and terrestrial carbon. However, in some lakes where the macrophytes had a distinct isotopic signature, our data suggest that macrophytes can represent an important carbon source to shallow lake food webs. [ABSTRACT FROM AUTHOR]

The addition of α-alumina to the aqueous solution of sodium alginate for imobilization of viable cells allows the production of denser particles than the ones obtained with sodium alginate alone. This biocatalyst was used in the continuous oxidation of ethanol to acetic acid, by a strain of Acetobacter isolated from an ethanol plant. The continuous fermentation was carried out in a circulating three-phase fluidized bed bioreactor. Denser particles allow a greater oxygen transfer, resulting in increased volumetric production rate of acetic acid, because oxygen is usually the limiting factor of this process. The performance of the biocatalyst was analyzed in terms of respiration rate, oxygen diffusivity, volumetric mass-transfer coefficient, and global productivity. [ABSTRACT FROM AUTHOR]