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  • Ismail Neergaard posted an update 1 day, 2 hours ago

    These changes were accompanied by an increased density of CART-, VAChT-, and nNOS-positive fibres. The results suggest that the enteric nervous system plays an important role in protecting the gastrointestinal tract during acrylamide intoxication.Spacer design in spiral-wound membranes (SWMs) significantly affects the axial pressuredrop in the flow channel but also the deposit layer removal. However, the effects of the spacerdesign and feed flow distribution in the module on the filtration performance have not yet beeninvestigated during the highly fouling-susceptible fractionation of proteins from skim milk bySWMs. Therefore, a parallel spacer with no turbulence promotion and a less homogeneous feedflow distribution in the SWM was compared to a diamond spacer with regard to its impact ondeposit formation and filtration performance. The experiments were conducted in a flat sheet testcell and in SWMs. learn more The parallel spacer induced a more homogeneous deposit layer formation.However, no difference in filtration performance could be observed in the experiments with the testcell. Even though deposit layer formation dominates the microfiltration, its amount and spatialdistribution could not be directly linked to the filtration performance. Furthermore, both spacerswere assessed in SWM. Despite the higher crossflow velocity applicable in the more open channelsof the parallel spacer, the performance of the parallel spacer was inferior to the diamond spacer.This was independent of the viscosity of the feed. Due to the high curvature of the membrane sheetsclose to the permeate collection tube, the cross-section of the flow channels in the SWM equippedwith the parallel spacer was reduced. This resulted in a distinctly lower deposit layer control andperformance, which could not be compensated by the resulting higher crossflow velocity far fromthe permeate collection tube.Mucosal associated invariant T-cells (MAIT cells) are activated following recognition of bacterial antigens (riboflavin intermediates) presented on major histocompatibility complex class I-related molecule (MR1). Our previous study showed that MR1-/- knock-out (KO) mice (lacking MAIT cells) harbor a unique microbiota that is resistant to antibiotic disruption and Clostridioides difficile colonization. While we have characterized the microbiota of this mouse strain, changes in global metabolic activity in these KO mice have not been assessed. Here, LC/MS-based untargeted metabolomics was applied to investigate the differences in the metabolome, specifically in the bile acid (BA) profile of wild-type (WT) and MR1-/- KO mice, as well as how antibiotics change these profiles. BA changes were evaluated in the intestinal content, cecum content, and stool samples from MR1-/- mice and WT mice treated with cefoperazone (Cef). Fecal pellets were collected daily and both intestinal and cecal contents were harvested at peviously reported microbiome data. Furthermore, the non-detected TCA and relatively higher DCA intensity in the KO mice might be related to Clostridioides difficile infection resistance, although this needs further investigation.One of the most widely used strategies for metabolite annotation in untargeted LCMS is based on the analysis of MSn spectra acquired using data-dependent acquisition (DDA), where precursor ions are sequentially selected from MS scans based on user-selected criteria. However, the number of MSn spectra that can be acquired during a chromatogram is limited and a trade-off between analytical speed, sensitivity and coverage must be ensured. In this research, we compare four different strategies for automated MS2 DDA, which can be easily implemented in the frame of standard QA/QC workflows for untargeted LC-MS. These strategies consist of (i) DDA in the MS working range; (ii) iterated DDA split into several m/z intervals; (iii) dynamic iterated DDA of (pre)selected potentially informative features; and (iv) dynamic iterated DDA of (pre)annotated metabolic features using a reference database. Their performance was assessed using the analysis of human milk samples as model example by comparing the percentage of LC-MS features selected as the precursor ion for MS2, the number, and class of annotated features, the speed and confidence of feature annotation, and the number of LC runs required.BACKGROUND With a growing number of users, social networking sites have been the subject of numerous recent studies, but little investigation has been given to their problematic use. OBJECTIVES Our main objective was to study the relationship between psychopathological variables (i.e., personality traits, depressive and anxiety symptoms, and stress) and problematic Facebook and Twitter use. PARTICIPANTS AND METHOD A sample of 1068 Internet users (Mage = 26.64; SD = 9.5) has been recruited online. Participants completed scales exploring problematic Facebook and Twitter use, and psychopathological variables. RESULTS Problematic Facebook and Twitter use were predicted by different pathological personality traits, regrouped in clusters in our study. Depressive and anxiety symptoms were also predictive of problematic Facebook and Twitter use but only stress explained problematic Facebook use. Gender differences have been observed. DISCUSSION This study highlights the relationship between depression, anxiety, stress, pathological personality traits, and problematic Facebook and Twitter use. Significant differences have been retrieved between these two uses and their relationship to psychopathology. Future research should also explore the causal relationship between social networking sites use and psychopathology and consider gender.FadD is an acyl-coenzyme A (CoA) synthetase specific for long-chain fatty acids (LCFA). Strains mutated in fadD cannot produce acyl-CoA and thus cannot grow on exogenous LCFA as the sole carbon source. Mutants in the fadD (smc02162) of Sinorhizobium meliloti are unable to grow on oleate as the sole carbon source and present an increased surface motility and accumulation of free fatty acids at the entry of the stationary phase of growth. In this study, we found that constitutive expression of the closest FadD homologues of S. meliloti, encoded by sma0150 and smb20650, could not revert any of the mutant phenotypes. In contrast, the expression of Escherichia coli fadD could restore the same functions as S. meliloti fadD. Previously, we demonstrated that FadD is required for the degradation of endogenous fatty acids released from membrane lipids. Here, we show that absence of a functional fadD provokes a significant loss of viability in cultures of E. coli and of S. meliloti in the stationary phase, demonstrating a crucial role of fatty acid degradation in survival capacity.