254 research outputs found
Language processing skills linked to FMR1 variation: A study of gaze-language coordination during rapid automatized naming among women with the FMR1 premutation
This work is licensed under a Creative Commons Attribution 4.0 International License.The FMR1 premutation (PM) is relatively common in the general population. Evidence suggests that PM carriers may exhibit subtle differences in specific cognitive and language abilities. This study examined potential mechanisms underlying such differences through the study of gaze and language coordination during a language processing task (rapid automatized naming; RAN) among female carriers of the FMR1 PM. RAN taps a complex set of underlying neuropsychological mechanisms, with breakdowns implicating processing disruptions in fundamental skills that support higher order language and executive functions, making RAN (and analysis of gaze/language coordination during RAN) a potentially powerful paradigm for revealing the phenotypic expression of the FMR1 PM. Forty-eight PM carriers and 56 controls completed RAN on an eye tracker, where they serially named arrays of numbers, letters, colors, and objects. Findings revealed a pattern of inefficient language processing in the PM group, including a greater number of eye fixations (namely, visual regressions) and reduced eye-voice span (i.e., the eyesâ lead over the voice) relative to controls. Differences were driven by performance in the latter half of the RAN arrays, when working memory and processing load are the greatest, implicating executive skills. RAN deficits were associated with broader social-communicative difficulties among PM carriers, and with FMR1-related molecular genetic variation (higher CGG repeat length, lower activation ratio, and increased levels of the fragile X mental retardation protein; FMRP). Findings contribute to an understanding of the neurocognitive profile of PM carriers and indicate specific gene-behavior associations that implicate the role of the FMR1 gene in language-related processes.NIH R01DC010191NIH R01MH091131NIH P30 HD0311
Population levels and geographical distribution of HIV RNA in rural Ugandan and Kenyan communities, including serodiscordant couples: a cross-sectional analysis.
BackgroundAs sub-Saharan Africa transitions to a new era of universal antiretroviral therapy (ART), up-to-date assessments of population-level HIV RNA suppression are needed to inform interventions to optimise ART delivery. We sought to measure population viral load metrics to assess viral suppression and characterise demographic groups and geographical locations with high-level detectable viraemia in east Africa.MethodsThe Sustainable East Africa Research in Community Health (SEARCH) study is a cluster-randomised controlled trial of an HIV test-and-treat strategy in 32 rural communities in Uganda and Kenya, selected on the basis of rural setting, having an approximate population of 10â000 people, and being within the catchment area of a President's Emergency Plan for AIDS Relief-supported HIV clinic. During the baseline population assessment in the SEARCH study, we did baseline HIV testing and HIV RNA measurement. We analysed stable adult (aged â„15 years) community residents. We defined viral suppression as a viral load of less than 500 copies per mL. To assess geographical sources of transmission risk, we established the proportion of all adults (both HIV positive and HIV negative) with a detectable viral load (local prevalence of viraemia). We defined transmission risk hotspots as geopolitical subunits within communities with an at least 5% local prevalence of viraemia. We also assessed serodiscordant couples, measuring the proportion of HIV-positive partners with detectable viraemia. The SEARCH study is registered with ClinicalTrials.gov, number NCT01864603.FindingsBetween April 2, 2013, and June 8, 2014, of 303â461 stable residents, we enumerated 274â040 (90·3%), of whom 132â030 (48·2%) were adults. Of these, 117â711 (89·2%) had their HIV status established, of whom 11â964 (10·2%) were HIV positive. Of these, we measured viral load in 8828 (73·8%) people. Viral suppression occurred in 3427 (81·6%) of 4202 HIV-positive adults on ART and 4490 (50·9%) of 8828 HIV-positive adults. Regional viral suppression among HIV-positive adults occurred in 881 (48·2%) of 1827 people in west Uganda, 516 (45·0%) of 1147 in east Uganda, and 3093 (52·8%) of 5854 in Kenya. Transmission risk hotspots occurred in three of 21 parishes in west Uganda and none in east Uganda and in 24 of 26 Kenya geopolitical subunits. In Uganda, 492 (2·9%) of 16â874 couples were serodiscordant: in 287 (58·3%) of these couples, the HIV-positive partner was viraemic (and in 69 [14·0%], viral load was >100â000 copies per mL). In Kenya, 859 (10·0%) of 8616 couples were serodiscordant: in 445 (53·0%) of these couples, the HIV-positive partner was viraemic (and in 129 [15%], viral load was >100â000 copies per mL).InterpretationBefore the start of the SEARCH trial, 51% of east African HIV-positive adults had viral suppression, reflecting ART scale-up efforts to date. Geographical hotspots of potential HIV transmission risk and detectable viraemia among serodiscordant couples warrant intensified interventions.FundingNational Institute of Allergy and Infectious Diseases (National Institutes of Health) and the President's Emergency Plan for AIDS Relief
Developing virtual and augmented reality applications for science, technology, engineering and math education
The Rhode Island IDeA Network of Biomedical Research Excellence Molecular Informatics Core at the University of Rhode Island Information Technology Services Innovative Learning Technologies developed virtual and augmented reality applications to teach concepts in biomedical science, including pharmacology, medicinal chemistry, cell culture and nanotechnology. The apps were developed as full virtual reality/augmented reality and 3D gaming versions, which do not require virtual reality headsets. Development challenges included creating intuitive user interfaces, text-to-voice functionality, visualization of molecules and implementing complex science concepts. In-app quizzes are used to assess the user\u27s understanding of topics, and user feedback was collected for several apps to improve the experience. The apps were positively reviewed by users and are being implemented into the curriculum at the University of Rhode Island
Genome Wide Association mapping of grain and straw biomass traits in the rice Bengal and Assam Aus Panel (BAAP) grown under alternate wetting and drying and permanently flooded irrigation
The bulk of this work was supported by the Biotechnology and Biological Sciences Research Council mostly from project BB/J003336/1 while a small part of the work by AT was also supported by project BB/N013492/1 (NEWS-India-UK). PR-a is studying for a Ph.D. funded by the Thai Government.Peer reviewedPublisher PD
It's the Recipient That Counts: Spending Money on Strong Social Ties Leads to Greater Happiness than Spending on Weak Social Ties
Previous research has shown that spending money on others (prosocial spending) increases happiness. But, do the happiness gains depend on who the money is spent on? Sociologists have distinguished between strong ties with close friends and family and weak tiesârelationships characterized by less frequent contact, lower emotional intensity, and limited intimacy. We randomly assigned participants to reflect on a time when they spent money on either a strong social tie or a weak social tie. Participants reported higher levels of positive affect after recalling a time they spent on a strong tie versus a weak tie. The level of intimacy in the relationship was more important than the type of relationship; there was no significant difference in positive affect after recalling spending money on a family member instead of a friend. These results add to the growing literature examining the factors that moderate the link between prosocial behaviour and happiness
Protemic identification of Germline Proteins in Caenorhabditis elegans
Sexual reproduction involves fusion of 2 haploid gametes to form diploid offspring with genetic contributions from both parents. Gamete formation represents a unique developmental program involving the action of numerous germline-specific proteins. In an attempt to identify novel proteins involved in reproduction and embryonic development, we have carried out a proteomic characterization of the process in Caenorhabditis elegans. To identify candidate proteins, we used 2D gel electrophoresis (2DGE) to compare protein abundance in nucleus-enriched extracts from wild-type C. elegans, and in extracts from mutant worms with greatly reduced gonads (glp-4(bn2) worms reared at 25°C); 84 proteins whose abundance correlated with germline presence were identified. To validate candidates, we used feeding RNAi to deplete candidate proteins, and looked for reduction in fertility and/or germline cytological defects. Of 20 candidates so screened for involvement in fertility, depletion of 13 (65%) caused a significant reduction in fertility, and 6 (30%) resulted in sterility (\u3c5 % of wild-type fertility). Five of the 13 proteins with demonstrated roles in fertility have not previously been implicated in germline function. The high frequency of defects observed after RNAi depletion of candidate proteins suggests that this approach is effective at identifying germline proteins, thus contributing to our understanding of this complex organ
Links between looking and speaking in autism and first-degree relatives: insights into the expression of genetic liability to autism
Abstract
Background
Rapid automatized naming (RAN; naming of familiar items presented in an array) is a task that taps fundamental neurocognitive processes that are affected in a number of complex psychiatric conditions. Deficits in RAN have been repeatedly observed in autism spectrum disorder (ASD), and also among first-degree relatives, suggesting that RAN may tap features that index genetic liability to ASD. This study used eye tracking to examine neurocognitive mechanisms related to RAN performance in ASD and first-degree relatives, and investigated links to broader language and clinical-behavioral features.
Methods
Fifty-one individuals with ASD, biological parents of individuals with ASD (nâ=â133), and respective control groups (nâ=â45 ASD controls; 58 parent controls) completed RAN on an eye tracker. Variables included naming time, frequency of errors, and measures of eye movement during RAN (eye-voice span, number of fixations and refixations).
Results
Both the ASD and parent-ASD groups showed slower naming times, more errors, and atypical eye-movement patterns (e.g., increased fixations and refixations), relative to controls, with differences persisting after accounting for spousal resemblance. RAN ability and associated eye movement patterns were correlated with increased social-communicative impairment and increased repetitive behaviors in ASD. Longer RAN times and greater refixations in the parent-ASD group were driven by the subgroup who showed clinical-behavioral features of the broad autism phenotype (BAP). Finally, parent-child dyad correlations revealed associations between naming time and refixations in parents with the BAP and increased repetitive behaviors in their child with ASD.
Conclusions
Differences in RAN performance and associated eye movement patterns detected in ASD and in parents, and links to broader social-communicative abilities, clinical features, and parent-child associations, suggest that RAN-related abilities might constitute genetically meaningful neurocognitive markers that can help bridge connections between underlying biology and ASD symptomatology
Two-year longitudinal survey reveals high genetic diversity of Schistosoma mansoni with adult worms surviving praziquantel treatment at the start of mass drug administration in Uganda
Background:
A key component of schistosomiasis control is mass drug administration with praziquantel. While control interventions have been successful in several endemic regions, mass drug administration has been less effective in others. Here we focus on the impact of repeated praziquantel treatment on the population structure and genetic diversity of Schistosoma mansoni.
Methods:
We examined S. mansoni epidemiology, population genetics, and variation in praziquantel susceptibility in parasites isolated from children across three primary schools in a high endemicity region at the onset of the Ugandan National Control Programme. Children were sampled at 11 timepoints over two years, including one week and four weeks post-praziquantel treatment to evaluate short-term impacts on clearance and evidence of natural variation in susceptibility to praziquantel.
Results:
Prevalence of S. mansoni was 85% at baseline. A total of 3576 miracidia larval parasites, isolated from 203 individual children, were genotyped at seven loci. Overall, genetic diversity was high and there was low genetic differentiation, indicating high rates of parasite gene flow. Schistosome siblings were found both pre-treatment and four weeks post-treatment, demonstrating adult worms surviving treatment and natural praziquantel susceptibility variation in these populations at the beginning of mass drug administration. However, we did not find evidence for selection on these parasites. While genetic diversity decreased in the short-term (four weeks post-treatment), diversity did not decrease over the entire period despite four rounds of mass treatment. Furthermore, within-host genetic diversity was affected by host age, host sex, infection intensity and recent praziquantel treatment.
Conclusions:
Our findings suggest that praziquantel treatments have short-term impacts on these parasite populations but impacts were transient and no long-term reduction in genetic diversity was observed. High gene flow reduces the likelihood of local adaptation, so even though parasites surviving treatment were observed, these were likely to be diluted at the beginning of the Ugandan National Control Programme. Together, these results suggest that MDA in isolation may be insufficient to reduce schistosome populations in regions with high genetic diversity and gene flow
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