Biology subjects

Arias Vasquez, A.

Publications and source records attributed to Arias Vasquez, A..

3 recordsLinked to original sources

bioRxiv2022

The role of the gut microbiota in patients with Kleefstra syndrome

Kleefstra Syndrome (KS) is a rare monogenetic syndrome, caused by haploinsufficiency of the EHMT1 gene, an important regulator of neurodevelopment. The clinical features of KS include intellectual disability, autistic behavior and gastrointestinal problems. The gut microbiota may constitute a, yet unexplored, mechanism underlying clinical variation, as they are an important modifier of the gut-brain-axis. To test whether variation in the gut microbiota is part of KS, we investigated the gut microbiota composition of 23 individuals with KS (patients) and 40 of their family members. Both alpha and beta diversity of patients were different from their family members. Genus Coprococcus 3 was lower in abundance in patients compared to family members. Moreover, abundance of genus Merdibacter was lower in patients versus family members, but only in the participants reporting intestinal complaints. Within the patient group, behavioral problems explained 7% variance in the beta diversity. Also, within this group, we detected higher levels of Coprococcus 3 and Atopobiaceae - uncultured associated with higher symptoms severity. Our results show significant differences in the gut microbiota composition of patients with KS compared to their family members, suggesting that these differences are part of the KS phenotype.

microbiology↗

bioRxiv2020

Quantitative Genetic Scoring, or how to put a number on an arbitrary genetic region

MotivationWith the increasing availability of genome-wide genetic data, methods to combine genetic variables with other sources of data in statistical models are required. This paper introduces quantitative genetic scoring (QGS), a dimensionality reduction method to create quantitative genetic variables representing arbitrary genetic regions. MethodsQGS is defined as the sum of absolute differences in the genetic sequence between a subject and a reference population. QGS properties such as distribution and sensitivity to region size were examined, and QGS was tested in six different existing genomic data sets of various sizes and various phenotypes. ResultsQGS can reduce genetic information by >98% yet explain phenotypic variance at low, medium, and high level of granularity. Associations based on QGS are independent of both size and linkage disequilibrium structure of the underlying region. In combination with stability selection, QGS finds significant results where a traditional genome-wide association approaches struggle. In conclusion, QGS preserves phenotypically significant genetic variance while reducing dimensionality, allowing researchers to include quantitative genetic information in any type of statistical analysis. Availabilityhttps://github.com/machine2learn/QGS Contactgido.schoenmacker@radboudumc.nl Supplemental informationSupplemental data are available online.

bioinformatics↗

bioRxiv2018

Stress matters: a double-blind, randomized controlled trial on the effects of a multispecies probiotic on neurocognition

Probiotics are microorganisms that can provide health benefits when consumed. Recent animal studies have demonstrated that probiotics can reverse gut microbiome-related alterations in anxiety and depression-like symptoms, in hormonal responses to stress, and in cognition. However, in humans, the effects of probiotics on neurocognition remain poorly understood and a causal understanding of the gut-brain link in emotion and cognition is lacking. We aimed to fill this gap by studying the effects of a probiotics intervention versus placebo on neurocognition in healthy human volunteers.\n\nWe set out to investigate the effects of a multispecies probiotic (Ecologic(R)Barrier) on specific neurocognitive measures of emotion reactivity, emotion regulation, and cognitive control using fMRI. Critically, we also tested whether the use of probiotics can buffer against the detrimental effects of acute stress on working memory. In a double blind, randomized, placebo-controlled, between-subjects intervention study, 58 healthy participants were tested twice, once before and once after 28 days of intervention with probiotics or placebo.\n\nProbiotics versus placebo did not affect emotion reactivity, emotion regulation, and cognitive control processes at brain or behavioral level, neither related self-report measures. However, relative to the placebo group, the probiotics group did show a significant stress-related increase in working memory performance after versus before supplementation (digit span backward, p=0.039, {eta}p2=.07). Interestingly, this change was associated with intervention-related neural changes in frontal cortex during cognitive control in the probiotics group, but not in the placebo group. Overall, our results show that neurocognitive effects of supplementation with a multispecies probiotic in healthy women become visible under challenging (stress) situations. Probiotics buffered against the detrimental effects of stress in terms of cognition, especially in those individuals with probiotics-induced changes in frontal brain regions during cognitive control.\n\nHighlightsO_LIWe ran a randomized placebo-controlled fMRI study with a multispecies probiotic\nC_LIO_LIProbiotics did not affect neurocognitive measures of emotion and cognitive control\nC_LIO_LIProbiotics did affect stress-related working memory and neural correlates\nC_LIO_LIProbiotics in healthy individuals can support cognition under stress\nC_LI

neuroscience↗