199 research outputs found
Diphtheria anti-toxoid antibody levels among pre-clinical students and staff in an institute of higher learning in Malaysia: are they protected?
Introduction: Little is known about the sero-prevalence of diphtheria anti-toxoid antibody levels among medical students in Malaysia. They too, just like other health care workers (HCWs) are at risk of contracting and transmitting diphtheria. Fortunately, this can be prevented by giving a specific vaccine: the diphtheria, tetanus and pertussis (DTP) vaccine. Nonetheless, data from local or regional
surveys are needed before any decision is made by the respective authorities. General objective: We studied the epidemiology of diphtheria anti-toxoid antibody levels and vaccination history amongst medical students and staff in Faculty of Medicine and Health Sciences, Universiti Putra Malaysia. Specific objectives: We determined the level of diphtheria anti-toxoid antibodies amongst pre-clinical
students and staff. Methodology: A total of 152 sera were collected from subjects aged 19 to 63, and diphtheria anti-toxoid levels were measured by an enzyme-linked immunosorbent assay. Results: One hundred and fifty-two (94.4%) blood samples out of 161 participants were successfully withdrawn, which comprised 105 (69.1%) and 47 (30.9%) medical students and staff, respectively. A total of 77.6% and the other 22.4% of the subjects had full and basic protection, respectively. Higher levels were predominant amongst males and they were 1.3 times more protected than females in 20-29 year-old group (85.1% vs 66.2%; odd ratios 1.25 [95% CI 1.03-1.50]; P=0.03). No significant difference in the levels of immunity among subjects for ethnicity and academic position (P>0.05). Recommendations: Level of full protection against diphtheria toxin should be clearly defined by broad population based studies using several comparable detection methods. Medical students and staff with basic protection
should be closely monitored or should be given a booster dose for those who are at high risk of acquiring
the disease. Thus, a standard degree of coverage should be clearly determined for health workers to prevent a potential outbreak. Conclusion: Students and staff possess immunity towards diptheria toxin however the level of full protective antibody is yet to be determined in future
Endemic, endangered and evolutionarily significant: cryptic lineages in Seychelles' frogs (Anura: Sooglossidae)
Cryptic diversity corresponding with island of origin has been previously reported in the endemic, geographically restricted sooglossid frogs of the Seychelles archipelago. The evolutionary pattern behind this has not been fully explored, and given current amphibian declines and the increased extinction risk faced by island species, we sought to identify evolutionarily significant units (ESUs) to address conservation concerns for these highly threatened anurans. We obtained genetic data for two mitochondrial (mtDNA) and four nuclear (nuDNA) genes from all known populations of sooglossid frog (on the islands of Mahé, Praslin and Silhouette) for phylogenetic analyses and to construct nuDNA haplotype networks. Bayesian and maximum likelihood analyses of mtDNA support the monophyly and molecular differentiation of populations in all species that occur on multiple islands. Haplotype networks using statistical parsimony revealed multiple high-frequency haplotypes shared between islands and taxa, in addition to numerous geographically distinct (island-specific) haplotypes for each species. We consider each island-specific population of sooglossid frog as an ESU and advise conservation managers to do likewise. Furthermore, our results identify each island lineage as a candidate species, evidence for which is supported by analyses of mtDNA based on Bayesian Poisson tree processes, and independent analyses of mtDNA and nuDNA using the multispecies coalescent. Our findings add to the growing understanding of the biogeography and hidden diversity within this globally important region
Exploring how socioeconomic status affects neighbourhood environments? : effects on obesity risks : a longitudinal study in Singapore
Research on how socioeconomic status interacts with neighbourhood characteristics to influence disparities in obesity outcomes is currently limited by residential segregation-induced structural confounding, a lack of empirical studies outside the U.S. and other 'Western' contexts, and an over-reliance on cross-sectional analyses. This study addresses these challenges by examining how socioeconomic status modifies the effect of accumulated exposures to obesogenic neighbourhood environments on children and mothers' BMI, drawing from a longitudinal mother-child birth cohort study in Singapore, an Asian city-state with relatively little residential segregation. We find that increased access to park connectors was associated with a decrease in BMI outcomes for mothers with higher socioeconomic status, but an increase for those with lower socioeconomic status. We also find that increased access to bus stops was associated with an increase in BMIz of children with lower socioeconomic status, but with a decrease in BMIz of children with higher socioeconomic status, while increased access to rail stations was associated with a decrease in BMIz of children with lower socioeconomic status only. Our results suggest that urban interventions might have heterogeneous effects by socioeconomic status.Peer reviewe
Chytrid Fungus (Batrachochytrium dendrobatidis) Undetected in the Two Orders of Seychelles Amphibians
Reports the first disease screening for chytrid Fungus (Batrachochytrium dendrobatidis) in amphibians across the Seychelles Archipelag
Pressure tunable quantum anomalous Hall states in a topological antiferromagnet
Mechanical modulation of the lattice parameter can modify the electronic
structure and manipulate the magnetic coupling of a material without
introducing impurities. Inspired by success in pressure-controlled magnetism,
we investigate the effect of hydrostatic pressure on quantized Chern states in
the antiferromagnetic topological insulator MnBi2Te4, using transport as a
probe. We show that pressure can enhance the robustness of quantum anomalous
Hall (QAH) phases that are otherwise delicate in 7SL MnBi2Te4 and in the
spin-flop (SF) state of 8SL MnBi2Te4. We explain our findings using a coupled
Dirac cone model of MnBi2Te4, which identifies stronger hybridization between
van der Waals layers as the driver of topological states. We further
demonstrate that moderate pressures readily available in laboratory systems can
provide reversible control of magnetic and topological phases. Our results
reveal a strong connection between the mechanical engineering of band topology
and magnetism.Comment: 11 pages, 4 figure
Exploring preconception signatures of metabolites in mothers with gestational diabetes mellitus using a non-targeted approach
BackgroundMetabolomic changes during pregnancy have been suggested to underlie the etiology of gestational diabetes mellitus (GDM). However, research on metabolites during preconception is lacking. Therefore, this study aimed to investigate distinctive metabolites during the preconception phase between GDM and non-GDM controls in a nested case-control study in Singapore.MethodsWithin a Singapore preconception cohort, we included 33 Chinese pregnant women diagnosed with GDM according to the IADPSG criteria between 24 and 28 weeks of gestation. We then matched them with 33 non-GDM Chinese women by age and pre-pregnancy body mass index (ppBMI) within the same cohort. We performed a non-targeted metabolomics approach using fasting serum samples collected within 12 months prior to conception. We used generalized linear mixed model to identify metabolites associated with GDM at preconception after adjusting for maternal age and ppBMI. After annotation and multiple testing, we explored the additional predictive value of novel signatures of preconception metabolites in terms of GDM diagnosis.ResultsA total of 57 metabolites were significantly associated with GDM, and eight phosphatidylethanolamines were annotated using HMDB. After multiple testing corrections and sensitivity analysis, phosphatidylethanolamines 36:4 (mean difference beta: 0.07; 95% CI: 0.02, 0.11) and 38:6 (beta: 0.06; 0.004, 0.11) remained significantly higher in GDM subjects, compared with non-GDM controls. With all preconception signals of phosphatidylethanolamines in addition to traditional risk factors (e.g., maternal age and ppBMI), the predictive value measured by area under the curve (AUC) increased from 0.620 to 0.843.ConclusionsOur data identified distinctive signatures of GDM-associated preconception phosphatidylethanolamines, which is of potential value to understand the etiology of GDM as early as in the preconception phase. Future studies with larger sample sizes among alternative populations are warranted to validate the associations of these signatures of metabolites and their predictive value in GDM.Peer reviewe
Dichotomy in the Impact of Elevated Maternal Glucose Levels on Neonatal Epigenome
Context Antenatal hyperglycemia is associated with increased risk of future adverse health outcomes in both mother and child. Variations in offspring's epigenome can reflect the impact and response to in utero glycemic exposure, and may have different consequences for the child. Objective We examined possible differences in associations of basal glucose status and glucose handling during pregnancy with both clinical covariates and offspring cord tissue DNA methylation. Research Design and Methods This study included 830 mother-offspring dyads from the Growing Up in Singapore Towards Healthy Outcomes cohort. The fetal epigenome of umbilical cord tissue was profiled using Illumina HumanMethylation450 arrays. Associations of maternal mid-pregnancy fasting (fasting plasma glucose [FPG]) and 2-hour plasma glucose (2hPG) after a 75-g oral glucose challenge with both maternal clinical phenotypes and offspring epigenome at delivery were investigated separately. Results Maternal age, prepregnancy body mass index, and blood pressure measures were associated with both FPG and 2hPG, whereas Chinese ethnicity (P = 1.9 x 10(-4)), maternal height (P = 1.1 x 10(-4)), pregnancy weight gain (P = 2.2 x 10(-3)), prepregnancy alcohol consumption (P = 4.6 x 10(-4)), and tobacco exposure (P = 1.9 x 10(-3)) showed significantly opposite associations between the 2 glucose measures. Most importantly, we observed a dichotomy in the effects of these glycemic indices on the offspring epigenome. Offspring born to mothers with elevated 2hPG showed global hypomethylation. CpGs most associated with the 2 measures also reflected differences in gene ontologies and had different associations with offspring birthweight. Conclusions Our findings suggest that 2 traditionally used glycemic indices for diagnosing gestational diabetes may reflect distinctive pathophysiologies in pregnancy, and have differential impacts on the offspring's DNA methylome.Peer reviewe
Dichotomy in the Impact of Elevated Maternal Glucose Levels on Neonatal Epigenome
Context Antenatal hyperglycemia is associated with increased risk of future adverse health outcomes in both mother and child. Variations in offspring's epigenome can reflect the impact and response to in utero glycemic exposure, and may have different consequences for the child. Objective We examined possible differences in associations of basal glucose status and glucose handling during pregnancy with both clinical covariates and offspring cord tissue DNA methylation. Research Design and Methods This study included 830 mother-offspring dyads from the Growing Up in Singapore Towards Healthy Outcomes cohort. The fetal epigenome of umbilical cord tissue was profiled using Illumina HumanMethylation450 arrays. Associations of maternal mid-pregnancy fasting (fasting plasma glucose [FPG]) and 2-hour plasma glucose (2hPG) after a 75-g oral glucose challenge with both maternal clinical phenotypes and offspring epigenome at delivery were investigated separately. Results Maternal age, prepregnancy body mass index, and blood pressure measures were associated with both FPG and 2hPG, whereas Chinese ethnicity (P = 1.9 x 10(-4)), maternal height (P = 1.1 x 10(-4)), pregnancy weight gain (P = 2.2 x 10(-3)), prepregnancy alcohol consumption (P = 4.6 x 10(-4)), and tobacco exposure (P = 1.9 x 10(-3)) showed significantly opposite associations between the 2 glucose measures. Most importantly, we observed a dichotomy in the effects of these glycemic indices on the offspring epigenome. Offspring born to mothers with elevated 2hPG showed global hypomethylation. CpGs most associated with the 2 measures also reflected differences in gene ontologies and had different associations with offspring birthweight. Conclusions Our findings suggest that 2 traditionally used glycemic indices for diagnosing gestational diabetes may reflect distinctive pathophysiologies in pregnancy, and have differential impacts on the offspring's DNA methylome.Peer reviewe
The theoretical and empirical basis of a BioPsychoSocial (BPS) risk screener for detection of older people's health related needs, planning of community programs, and targeted care interventions
Background This study introduces the conceptual basis and operational measure, ofBioPyschoSocial (BPS) healthand related risk to better understand how well older people are managing and to screen for risk status. The BPS Risk Screener is constructed to detectvulnerabilityat older ages, and seeks to measure dynamic processes that place equal emphasis on Psycho-emotional and Socio-interpersonal risks, as Bio-functional ones. We validate the proposed measure and describe its application to programming. Methods We undertook a quantitative cross-sectional, psychometric study withn = 1325 older Singaporeans, aged 60 and over. We adapted the EASYCare 2010 and Lubben Social Network Scale questionnaires to help determine the BPS domains using factor analysis from which we derive the BPS Risk Screener items. We then confirm its structure, and test the scoring system. The score is initially validated against self-reported general health then modelled against: number of falls; cognitive impairment; longstanding diseases; and further tested against service utilization (linked administrative data). Results Three B, P and S clusters are defined and identified and a BPSmanaging score(‘doing’ well, or ‘some’, ‘many’, and ‘overwhelming problems’) calculated such that the risk of problematic additive BPS effects, what we term health‘loads’, are accounted for. Thirty-five items (factor loadings over 0.5) clustered into three distinct B, P, S domains and were found to be independently associated with self-reported health: B: 1.99 (1.64 to 2.41), P: 1.59 (1.28 to 1.98), S: 1.33 (1.10 to 1.60). The fit improved when combined into the managing score 2.33 (1.92 to 2.83, < 0.01). The score was associated with mounting risk for all outcomes. Conclusions BPS domain structures, and the novel scoring system capturing dynamic BPS additive effects, which can combine to engender vulnerability, are validated through this analysis. The resulting tool helps render clients’ risk status and related intervention needs transparent. Given its explicit and empirically supported attention to P and S risks, which have the potential to be more malleable than B ones, especially in the older old, this tool is designed to be change sensitive
Prenatal maternal depression alters amygdala functional connectivity in 6-month-old infants
10.1038/tp.2015.3Translational Psychiatry52GUSTO (Growing up towards Healthy Outcomes
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