128 research outputs found
Evidence of gene-environment interaction for two genes on chromosome 4 and environmental tobacco smoke in controlling the risk of nonsyndromic cleft palate
Nonsyndromic cleft palate (CP) is one of the most common human birth defects and both genetic and environmental risk factors contribute to its etiology. We conducted a genome-wide association study (GWAS) using 550 CP case-parent trios ascertained in an international consortium. Stratified analysis among trios with different ancestries was performed to test for GxE interactions with common maternal exposures using conditional logistic regression models. While no single nucleotide polymorphism (SNP) achieved genome-wide significance when considered alone, markers in SLC2A9 and the neighboring WDR1 on chromosome 4p16.1 gave suggestive evidence of gene-environment interaction with environmental tobacco smoke (ETS) among 259 Asian trios when the models included a term for GxE interaction. Multiple SNPs in these two genes were associated with increased risk of nonsyndromic CP if the mother was exposed to ETS during the peri-conceptual period (3 months prior to conception through the first trimester). When maternal ETS was considered, fifteen of 135 SNPs mapping to SLC2A9 and 9 of 59 SNPs in WDR1 gave P values approaching genome-wide significance (10-6<P<10-4) in a test for GxETS interaction. SNPs rs3733585 and rs12508991 in SLC2A9 yielded P = 2.26×10-7 in a test for GxETS interaction. SNPs rs6820756 and rs7699512 in WDR1 also yielded P = 1.79×10-7 and P = 1.98×10-7 in a 1 df test for GxE interaction. Although further replication studies are critical to confirming these findings, these results illustrate how genetic associations for nonsyndromic CP can be missed if potential GxE interaction is not taken into account, and this study suggest SLC2A9 and WDR1 should be considered as candidate genes for CP. © 2014 Wu et al
Exam Sequence and Timing as Predictors of COMLEX-USA and USMLE Performance in Osteopathic Medical Students
Maurice Blodgett,1 Martin Schmidt,2 Jennifer S Beaty,3 Brian Pinney,4 Bryan Hays5 1Department of Primary Care, Des Moines University, West Des Moines, IA, USA; 2Department of Biochemistry and Nutrition, Des Moines University, West Des Moines, IA, USA; 3Department of Specialty Medicine, Des Moines University, West Des Moines, IA, USA; 4Center for Educational Enhancement, Des Moines University, West Des Moines, IA, USA; 5Registrar’s Office, Des Moines University, West Des Moines, IA, USACorrespondence: Maurice Blodgett, Email [email protected]: This study examined the impact of exam sequence and timing on the performance of osteopathic medical students on the COMLEX-USA Level 1 and Level 2 and USMLE Step 1 and Step 2 examinations.Methods: Two cohorts were analyzed: 364 osteopathic medical students who completed both COMLEX-USA Level 1 and USMLE Step 1 between 2020 and 2022 (prior to the implementation of pass/fail grading), and 734 osteopathic medical students who completed both COMLEX-USA Level 2 and USMLE Step 2 between 2021 and 2025. Student performance was evaluated based on the sequence of examinations and intervals between them. Because the scores did not follow a normal distribution, as indicated by the Shapiro–Wilk test, the Mann–Whitney U-test was employed to compare the median scores between the groups.Results: Osteopathic medical students who undertook the USMLE examinations first consistently achieved higher scores than those who undertook the COMLEX-USA examinations first across most academic quartiles. Shorter exam intervals (1– 7 days) were associated with higher scores, whereas longer intervals (≥ 8 days) were correlated with significantly lower scores. The effects of exam order and timing varied across performance quartiles, with lower-performing students deriving the greatest benefit from taking the USMLE examinations first and maintaining shorter intervals between the exams.Conclusion: Strategic scheduling of exams may enhance performance on both the COMLEX-USA and USMLE examinations, particularly for lower-performing students. However, individual factors should be considered when implementing these strategies. These findings offer valuable insights for osteopathic medical students and educators in planning exam preparation and scheduling.Keywords: medical licensure assessment, standardized board examinations, test preparation strategies, score outcome correlatio
Identifying divergent design thinking through the observable behavior of service design novices
© 2018, Springer Nature B.V. Design thinking holds the key to innovation processes, but is often difficult to detect because of its implicit nature. We undertook a study of novice designers engaged in team-based design exercises in order to explore the correlation between design thinking and designers’ physical (observable) behavior and to identify new, objective, design thinking identification methods. Our study addresses the topic by using data collection method of “think aloud” and data analysis method of “protocol analysis” along with the unconstrained concept generation environment. Collected data from the participants without service design experience were analyzed by open and selective coding. Through the research, we found correlations between physical activity and divergent thinking, and also identified physical behaviors that predict a designer’s transition to divergent thinking. We conclude that there are significant relations between designers’ design thinking and the behavioral features of their body and face. This approach opens possible new ways to undertake design process research and also design capability evaluation
BluePort: A Platform to Study the Eosinophilic Response of Mice to the Bite of a Vector of Leishmania Parasites, Lutzomyia longipalpis Sand Flies
transmission in residents of endemic areas has been attributed to the acquisition of immunity to sand fly salivary proteins. One theoretical way to accelerate the acquisition of this immunity is to increase the density of antigen-presenting cells at the sand fly bite site. Here we describe a novel tissue platform that can be used for this purpose. sand flies. Results presented indicate that a shift in the inflammatory response, from neutrophilic to eosinophilic, is the main histopathological feature associated with the immunity acquired through repeated exposure to the bite of sand flies, and that the BluePort tissue compartment could be used to accelerate this process. In addition, changes observed inside the BluePort parenchyma indicate that it could be used to study complex immunobiological processes, and to develop ectopic secondary lymphoid structures.Understanding the characteristics of the dermal response to the bite of sand flies is a critical element of strategies to control leishmaniasis using vaccines that target salivary proteins. Finding that dermal eosinophilia is such a prominent component of the anti-salivary immunity induced by repeated exposure to sand fly bites raises one important consideration: how to avoid the immunological conflict derived from a protective Th2-driven immunity directed to sand fly saliva with a protective Th1-driven immunity directed to the parasite. The BluePort platform is an ideal tool to address experimentally this conundrum
Unique Type I Interferon Responses Determine the Functional Fate of Migratory Lung Dendritic Cells during Influenza Virus Infection
Migratory lung dendritic cells (DCs) transport viral antigen from the lungs to the draining mediastinal lymph nodes (MLNs) during influenza virus infection to initiate the adaptive immune response. Two major migratory DC subsets, CD103+ DCs and CD11bhigh DCs participate in this function and it is not clear if these antigen presenting cell (APC) populations become directly infected and if so whether their activity is influenced by the infection. In these experiments we show that both subpopulations can become infected and migrate to the draining MLN but a difference in their response to type I interferon (I-IFN) signaling dictates the capacity of the virus to replicate. CD103+ DCs allow the virus to replicate to significantly higher levels than do the CD11bhigh DCs, and they release infectious virus in the MLNs and when cultured ex-vivo. Virus replication in CD11bhigh DCs is inhibited by I-IFNs, since ablation of the I-IFN receptor (IFNAR) signaling permits virus to replicate vigorously and productively in this subset. Interestingly, CD103+ DCs are less sensitive to I-IFNs upregulating interferon-induced genes to a lesser extent than CD11bhigh DCs. The attenuated IFNAR signaling by CD103+ DCs correlates with their described superior antigen presentation capacity for naïve CD8+ T cells when compared to CD11bhigh DCs. Indeed ablation of IFNAR signaling equalizes the competency of the antigen presenting function for the two subpopulations. Thus, antigen presentation by lung DCs is proportional to virus replication and this is tightly constrained by I-IFN. The “interferon-resistant” CD103+ DCs may have evolved to ensure the presentation of viral antigens to T cells in I-IFN rich environments. Conversely, this trait may be exploitable by viral pathogens as a mechanism for systemic dissemination
Population Genomics of Parallel Adaptation in Threespine Stickleback using Sequenced RAD Tags
Next-generation sequencing technology provides novel opportunities for gathering genome-scale sequence data in natural populations, laying the empirical foundation for the evolving field of population genomics. Here we conducted a genome scan of nucleotide diversity and differentiation in natural populations of threespine stickleback (Gasterosteus aculeatus). We used Illumina-sequenced RAD tags to identify and type over 45,000 single nucleotide polymorphisms (SNPs) in each of 100 individuals from two oceanic and three freshwater populations. Overall estimates of genetic diversity and differentiation among populations confirm the biogeographic hypothesis that large panmictic oceanic populations have repeatedly given rise to phenotypically divergent freshwater populations. Genomic regions exhibiting signatures of both balancing and divergent selection were remarkably consistent across multiple, independently derived populations, indicating that replicate parallel phenotypic evolution in stickleback may be occurring through extensive, parallel genetic evolution at a genome-wide scale. Some of these genomic regions co-localize with previously identified QTL for stickleback phenotypic variation identified using laboratory mapping crosses. In addition, we have identified several novel regions showing parallel differentiation across independent populations. Annotation of these regions revealed numerous genes that are candidates for stickleback phenotypic evolution and will form the basis of future genetic analyses in this and other organisms. This study represents the first high-density SNP–based genome scan of genetic diversity and differentiation for populations of threespine stickleback in the wild. These data illustrate the complementary nature of laboratory crosses and population genomic scans by confirming the adaptive significance of previously identified genomic regions, elucidating the particular evolutionary and demographic history of such regions in natural populations, and identifying new genomic regions and candidate genes of evolutionary significance
TGFA/Taq I polymorphism and environmental factors in non-syndromic oral clefts in Southern Brazil
We report a study of TGFA/ Taq I polymorphisms and environmental factors in non-syndromic oral cleft in Southern Brazil. Nonsyndromic cleft case-parent triads were recruited to participate. Clinical data was collected with an emphasis on tobacco and alcohol use during pregnancy. DNA was extracted from peripheral blood and TGFA/ Taq I polymorphisms were analyzed by PCR/RFLP with Taq I restriction enzyme. Association of clefts and TGFA/ Taq I polymorphisms was determined using a transmission disequilibrium test (TDT). Association of environmental factors, clefts, and genotypes was evaluated with Fisher's exact test. The minor allele frequency was 0.064. We found no evidence of association between TGFA/ Taq I polymorphisms and clefting (TDT p = 0.335). We also found no association between TGFA/ TaqI polymorphisms and environmental factors (alcohol and/or tobacco). Therefore, no evidence was found that TGFA/ Taq I polymorphisms play a role in clefting in this population. No evidence was found that tobacco or alcohol exposure during pregnancy was related to clefting, however a larger sample size is needed to confirm these results
Role of biomechanics in the understanding of normal, injured, and healing ligaments and tendons
Ligaments and tendons are soft connective tissues which serve essential roles for biomechanical function of the musculoskeletal system by stabilizing and guiding the motion of diarthrodial joints. Nevertheless, these tissues are frequently injured due to repetition and overuse as well as quick cutting motions that involve acceleration and deceleration. These injuries often upset this balance between mobility and stability of the joint which causes damage to other soft tissues manifested as pain and other morbidity, such as osteoarthritis
Modern epidemiology and its discontents
The goal of this article is to present a snapshot of an ongoing debate within epidemiology, pitching opposing sides in the struggle to define the path it should follow in the years to come. The debate among epidemiologists in the mid-90s pitted those who defended the idea that epidemiology should necessarily deal with a wide context against those who believed that science and public health are better served by focusing on the individual level. Ian Hacking’s concept of styles of reasoning was used as a theoretical tool. The literature was reviewed using a core set of articles as an entry point, seeking articles that cited them, and then back-tracking the citations of the resulting set in the Scopus database. The main arguments are presented according to levels (ontological, epistemological, axiological and pragmatic), in order to show an even deeper disagreement, in the very conception of science and its relation to social issues and public policy
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