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Kori, M.

Publications and source records attributed to Kori, M..

3 recordsLinked to original sources

Cell-type specific auditory responses in the striatum are shaped by feed forward inhibition

Summary/AbstractThe posterior "tail" region of the striatum receives dense innervation from sensory brain regions and has been demonstrated to play a role in behaviors that require sensorimotor integration including discrimination1,2, avoidance3 and defense4 responses. The output neurons of the striatum, the D1 and D2 striatal projection neurons (SPNs) that make up the direct and indirect pathways, respectively, are thought to play differential roles in these behavioral responses, although it remains unclear if or how these neurons display differential responsivity to sensory stimuli. Here, we used whole-cell recordings in vivo and ex vivo to examine the strength of excitatory and inhibitory synaptic inputs onto D1 and D2 SPNs following the stimulation of upstream auditory pathways. While D1 and D2 SPNs both displayed stimulus-evoked depolarizations, D1 SPN responses were stronger and faster for all stimuli tested in vivo as well as in brain slices. This difference did not arise from differences in the strength of excitatory inputs but from differences in the strength of feed forward inhibition. Indeed, fast spiking interneurons, which are readily engaged by auditory afferents exerted stronger inhibition onto D2 SPNs compared to D1 SPNs. Our results support a model in which differences in feed forward inhibition enable the preferential recruitment of the direct pathway in response to auditory stimuli, positioning this pathway to initiate sound-driven actions.

neuroscience↗

Computational investigations in inhibition of alcohol/aldehyde dehydrogenase in lignocellulosic hydrolysates

Second generation alcoholic biofuels synthesis from lignocellulosic biomass (LB) consists three steps viz., pre-treatment, detoxification, and fermentation. This dilute acid pre-treatment process generates several compounds like acids, aldehydes, ketones, oxides and their phenolic derivatives that are potential inhibitors of some of the crucial enzymes in the metabolic pathway of ABE fermentation. With application of hybrid quantum mechanics/ molecular mechanics (QM/MM) approach, our aim is to discern the molecular mechanism of inhibition of key AADs across solventogenic species. The objectives of present study are: (1) identification and homology modelling of key AADs; (2) validation, quality assessment and physiochemical characterization of the modelled enzymes; (3) identification, construction and optimization of chemical structure of potent microbial inhibitors in LH; and (4) applications of hybrid QM/MM simulations to profile the molecular interactions between microbial inhibitors and key AADs. Our computational investigation has revealed various important facets of inhibition of the AAD enzymes, which could guide structural biologist in designing efficient and robust enzymes. Moreover, our methodology also provides a general framework which could applied for deciphering the molecular mechanism of inhibition behaviour of other enzymes. HighlightsO_LIHomology modelling of 7 alcohol/aldehyde dehydrogenase (AAD) in solventogenic Clostridia C_LIO_LIIdentification and structural optimization of potent microbial inhibitors in lignocellulosic hydrolysates C_LIO_LIQM/MM simulations to profile the molecular interactions between 10 inhibitors and 7 AADs C_LIO_LIDiscernment of the molecular mechanism of inhibition of key alcohol/aldehyde dehydrogenase C_LIO_LIA methodological framework for deciphering the molecular mechanism of enzyme inhibition C_LI

bioinformatics↗

Treatment-Specific Composition of Gut Microbiota Is Associated with Disease Remission in a Pediatric Crohn’s Disease Cohort

BackgroundThe beneficial effects of antibiotics in Crohns disease (CD) depend in part on the gut microbiota but are inadequately understood. We investigated the impact of metronidazole (MET) and metronidazole plus azithromycin (MET+AZ) on the microbiota in pediatric CD, and the use of microbiota features as classifiers or predictors of disease remission.\n\nMethods16S rRNA-based microbiota profiling was performed on stool samples from 67 patients in a multinational, randomized, controlled, longitudinal, 12-week trial of MET vs. MET+AZ in children with mild to moderate CD. Profiles were analyzed together with disease activity, and then used to construct Random Forest models to classify remission or predict treatment response.\n\nResultsBoth MET and MET+AZ significantly decreased diversity of the microbiota and caused large treatment-specific shifts in microbiota structure at week 4. Disease remission was associated with a treatment-specific microbiota configuration. Random Forest models constructed from microbiota profiles pre- and during antibiotic treatment with metronidazole accurately classified disease remission in this treatment group (AUC of 0.879, 95% CI 0.683, 0.9877; sensitivity 0.7778; specificity 1.000, P < 0.001). A Random Forest model trained on preantibiotic microbiota profiles predicted disease remission at week 4 with modest accuracy (AUC of 0.8, P = 0.24).\n\nConclusionsMET and MET+AZ antibiotic regimens in pediatric CD lead to distinct gut microbiota structures at remission. It may be possible to classify and predict remission based in part on microbiota profiles, but larger cohorts will be needed to realize this goal.\n\nSummaryWe investigated the impact of metronidazole and metronidazole plus azithromycin on the gut microbiota in pediatric Crohns disease. Disease remission was associated with a treatment-specific microbiota configuration, and could be predicted based on pre-antibiotic microbiota profiles.

microbiology↗