1,027 research outputs found
Case Report: Exome Sequencing Identified a Novel Frameshift Mutation of α-Actin 1 in a Chinese Family With Macrothrombocytopenia and Mild Bleeding
Inherited macrothrombocytopenia (IMTP) is a rare disorder characterized by a reduced platelet count and abnormally large platelets. The main clinical symptom of IMTP is mild bleeding in some patients. At present, more than 30 genes have been identified in patients with syndromic and non-syndromic IMTP. In this study, a 3-year-old boy and his mother who presented with mild epistaxis and/or gingival bleeding were diagnosed as having IMTP. Wen then selected whole sequencing to explore the genetic lesion of the patients. After data filtering and mutation validation, a novel frameshift mutation (NM_001130004: c.398_399insTGCG, p.F134AfsX60) of α-actin 1 (ACTN1) was identified in the proband and his mother but absent in other unaffected individuals. Previous studies have proven that mutations in ACTN1 may lead to IMTP with mild to absent bleeding phenotype. The novel mutation, resulting in a truncated protein in exon 4 of the ACTN1 gene, was absent in the public database, such as 1000G and genomAD. Further Western blot revealed that the expression of α-actin 1 in the proband was decreased overtly, which indicated that the novel frameshift mutation may induce non-sense-mediated mRNA decay. In summary, this study not only broadened the variants spectrum of ACTN1 gene, which may contribute to the genetic counseling of IMTP, but also confirmed the diagnosis of IMTP, which may help the management and prognosis for the family members
Nonmonotonic Effect Of Chemical Heterogeneity On Interfacial Crack Growth At High-angle Grain Boundaries In Fe-Ni-Cr Alloys
An intermittent pattern is observed in the modeling of interfacial cyclic-loading crack growth at high-angle grain boundaries in ternary Fe-Ni-Cr alloys. Different from conventional wisdom of stress-intensity factor, the abrupt crack advances are found driven by extreme value statistics - namely, the aggregation of atoms with most compressive residual stresses. In addition, inherently non-affine atomic stress fluctuations are discovered, and the fluctuations peak at intermediate level of chemical heterogeneity, causing the fastest crack growth. Implications of such nonmonotonic mechanism in regard to the origin of intermediate-temperature embrittlement phenomena are also discussed
Association of maternal prenatal copper concentration with gestational duration and preterm birth: a multicountry meta-analysis Author links open overlay panel.
Background: Copper (Cu), an essential trace mineral regulating multiple actions of inflammation and oxidative stress, has been implicated in risk for preterm birth (PTB).
Objectives: This study aimed to determine the association of maternal Cu concentration during pregnancy with PTB risk and gestational duration in a large multicohort study including diverse populations.
Methods: Maternal plasma or serum samples of 10,449 singleton live births were obtained from 18 geographically diverse study cohorts. Maternal Cu concentrations were determined using inductively coupled plasma mass spectrometry. The associations of maternal Cu with PTB and gestational duration were analyzed using logistic and linear regressions for each cohort. The estimates were then combined using meta-analysis. Associations between maternal Cu and acute-phase reactants (APRs) and infection status were analyzed in 1239 samples from the Malawi cohort.
Results: The maternal prenatal Cu concentration in our study samples followed normal distribution with mean of 1.92 μg/mL and standard deviation of 0.43 μg/mL, and Cu concentrations increased with gestational age up to 20 wk. The random-effect meta-analysis across 18 cohorts revealed that 1 μg/mL increase in maternal Cu concentration was associated with higher risk of PTB with odds ratio of 1.30 (95% confidence interval [CI]: 1.08, 1.57) and shorter gestational duration of 1.64 d (95% CI: 0.56, 2.73). In the Malawi cohort, higher maternal Cu concentration, concentrations of multiple APRs, and infections (malaria and HIV) were correlated and associated with greater risk of PTB and shorter gestational duration.
Conclusions: Our study supports robust negative association between maternal Cu and gestational duration and positive association with risk for PTB. Cu concentration was strongly correlated with APRs and infection status suggesting its potential role in inflammation, a pathway implicated in the mechanisms of PTB. Therefore, maternal Cu could be used as potential marker of integrated inflammatory pathways during pregnancy and risk for PTB
Risk Prediction for Sudden Cardiac Death in the General Population: A Systematic Review and Meta-Analysis
Objective: Identification of SCD risk is important in the general population from a public health perspective. The objective is to summarize and appraise the available prediction models for the risk of SCD among the general population.Methods: Data were obtained searching six electronic databases and reporting prediction models of SCD risk in the general population. Studies with duplicate cohorts and missing information were excluded from the meta-analysis.Results: Out of 8,407 studies identified, fifteen studies were included in the systematic review, while five studies were included in the meta-analysis. The Cox proportional hazards model was used in thirteen studies (96.67%). Study locations were limited to Europe and the United States. Our pooled meta-analyses included four predictors: diabetes mellitus (ES = 2.69, 95%CI: 1.93, 3.76), QRS duration (ES = 1.16, 95%CI: 1.06, 1.26), spatial QRS-T angle (ES = 1.46, 95%CI: 1.27, 1.69) and factional shortening (ES = 1.37, 95%CI: 1.15, 1.64).Conclusion: Risk prediction model may be useful as an adjunct for risk stratification strategies for SCD in the general population. Further studies among people except for white participants and more accessible factors are necessary to explore
Transcriptomics of Gabra4 knockout mice reveals common NMDAR pathways underlying autism, memory, and epilepsy
Autism spectrum disorder (ASD) is a neuronal developmental disorder with impaired social interaction and communication, often with abnormal intelligence and comorbidity with epilepsy. Disturbances in synaptic transmission, including the GABAergic, glutamatergic, and serotonergic systems, are known to be involved in the pathogenesis of this disorder, yet we do not know if there is a common molecular mechanism. As mutations in the GABAergic receptor subunit gene GABRA4 are reported in patients with ASD, we eliminated the Gabra4 gene in mice and found that the Gabra4 knockout mice showed autistic-like behavior, enhanced spatial memory, and attenuated susceptibility to pentylenetetrazol-induced seizures, a constellation of symptoms resembling human high-functioning autism. To search for potential molecular pathways involved in these phenotypes, we performed a hippocampal transcriptome profiling, constructed a hippocampal interactome network, and revealed an upregulation of the NMDAR system at the center of the converged pathways underlying high-functioning autism-like and anti-epilepsy phenotypes
A Lactobacillus-Deficient Vaginal Microbiota Dominates Postpartum Women in Rural Malawi.
The bacterial community found in the vagina is an important determinant of a woman's health and disease status. A healthy vaginal microbiota is associated with low species richness and a high proportion of one of a number of different Lactobacillus spp. When disrupted, the resulting abnormal vaginal microbiota is associated with a number of disease states and poor pregnancy outcomes. Studies up until now have concentrated on relatively small numbers of American and European populations that may not capture the full complexity of the community or adequately predict what constitutes a healthy microbiota in all populations. In this study, we sampled and characterized the vaginal microbiota found on vaginal swabs taken postpartum from a cohort of 1,107 women in rural Malawi. We found a population dominated by Gardnerella vaginalis and devoid of the most common vaginal Lactobacillus species, even if the vagina was sampled over a year postpartum. This Lactobacillus-deficient anaerobic community, commonly labeled community state type (CST) 4, could be subdivided into four further communities. A Lactobacillus iners-dominated vaginal microbiota became more common the longer after delivery the vagina was sampled, but G. vaginalis remained the dominant organism. These results outline the difficulty in all-encompassing definitions of what a healthy or abnormal postpartum vaginal microbiota is. Previous identification of community state types and associations among bacterial species, bacterial vaginosis, and adverse birth outcomes may not represent the complex heterogeneity of the microbiota present. (This study has been registered at ClinicalTrials.gov as NCT01239693.)IMPORTANCE A bacterial community in the vaginal tract is dominated by a small number of Lactobacillus species, and when not present there is an increased incidence of inflammatory conditions and adverse birth outcomes. A switch to a vaginal bacterial community lacking in Lactobacillus species is common after pregnancy. In this study, we characterized the postpartum vaginal bacterial community of a large group of women from a resource-poor, undersampled population in rural Malawi. The majority of women were found to have a Lactobacillus-deficient community, and even when sampled a year after delivery the majority of women still did not have Lactobacillus present in their vaginal microbiota. The effect of becoming pregnant again for those who do not revert to a Lactobacillus-dominant community is unknown, and this could suggest that not all Lactobacillus-deficient community structures are adverse. A better understanding of this complex community state type is needed
Prevalence and Subtype Distribution of Blastocystis in Tibetan Sheep in Qinghai Province, Northwestern China.
peer reviewedBlastocystis is one of the most common intestinal protists in humans and a great number of animals, including sheep and goats. High prevalence and multiple subtypes of Blastocystis have been reported in sheep in several regions of China and elsewhere. However, there is a dearth of knowledge about Blastocystis in Tibetan sheep. A total of 761 fecal samples were collected from Tibetan sheep in seven counties of Qinghai Province, northwestern China, and were examined for the prevalence and subtypes of Blastocystis using molecular technology based on the partial small subunit ribosomal RNA gene of Blastocystis. The overall prevalence of Blastocystis in the investigated Tibetan sheep was 7.5% (57/761) using PCR and DNA Sanger sequencing, and differences in prevalence were observed among the ruminants from the seven counties (P < 0.01), and across four seasons (P < 0.01). Sequence analysis revealed five subtypes (ST14 (57.9%), ST10 (26.3%), ST12 (5.3%), ST21 (5.3%), and ST30 (5.3%)) of Blastocystis sp. in these Tibetan sheep, with ST14 as the predominant subtype. To our knowledge, this is the first report of Blastocystis colonization in Tibetan sheep
Immunity duration of a recombinant adenovirus type-5 vector-based Ebola vaccine and a homologous prime-boost immunisation in healthy adults in China: fi nal report of a randomised, double-blind, placebo-controlled, phase 1 trial
Background The 2013–15 Ebola virus disease epidemic in west Africa greatly accelerated the development of Ebola
vaccine. We aimed to analyse the immune persistence induced by one shot of an adenovirus type-5 vector-based
Ebola virus vaccine up to 6 months and the eff ect of boosting with a homologous vector in healthy adults in China.
Methods In a randomised, double-blind, placebo-controlled, phase 1 clinical trial in one site in Jiangsu Province,
China, 120 healthy adults aged 18–60 years received an initial dose of intramuscular adenovirus type-5 Ebola virus
vaccine of 4·0 × 10¹⁰ viral particles, 1·6 × 10¹¹ viral particles, or placebo, and were followed up to day 168. Participants
were subsequently re-recruited to receive a booster dose of the same vaccine or placebo, in the same dose, at month 6.
Women who were pregnant, breastfeeding, or planned to become pregnant during the next month were excluded.
Randomisation was conducted by computer-generated block randomisation. Randomisation data were unmasked for
interim analysis of the data obtained between days 0–28 but not disclosed to participants or site staff . Safety and
immunogenicity analysis were done on the intention-to-treat population. We aimed to assess the safety profi le of the
experimental vaccine and the immunity responses to a single-dose immunisation or a homologous prime-boost
regimen. Primary outcomes were Ebola glycoprotein-specifi c ELISA antibody responses 28 days post-boost and the
occurrences of adverse reactions post-boost. The original trial and the extended booster study were registered with
ClinicalTrials.gov, numbers NCT02326194 and NCT02533791, respectively.
Findings Between Dec 28, 2014, and Jan 9, 2015, we enrolled 210 volunteers. 90 participants were not randomised due
to not meeting inclusion criteria (61), meeting exclusion criteria (4), or withdrawal of consent (25). 120 people were
randomly assigned to receive intramuscular Ebola vaccine at 4·0 × 10¹⁰ viral particles (low dose, n=40), Ebola vaccine
at 1·6 × 10¹¹ viral particles (high dose, n=40), or placebo (n=40, in two groups of 20). After prime vaccination, the
geometric mean titer (GMT) of ELISA EC90 peaked at 682·7 (95% CI 424·3–1098·5) in the low-dose vaccine group
and 1305·7 (970·1–1757·2) in the high-dose vaccine group at day 28, and then fell gradually through the next a few
months to 575·5 (394·8–838·8) in the high-dose vaccine group and 197·9 (107·9–362·7) in the low-dose vaccine
group at day 168. No specific response was recorded in the placebo group with a GMT of 5·0. Of the 120 participants
involved in the initial trial, ten participants declined to participate, and 110 were included in the boost immunisation:
38 received the low dose, 35 received the high dose, and 37 received the placebo. At day 28 after boost vaccination, the
ELISA EC90 titres rapidly rose to 6110 (95% CI 4705–7935) in the low-dose group and to 11825 (8904–15705) in the
high dose group. 78 of 110 participants reported at least one solicited adverse reaction within the fi rst 7 days after
booster administration. Both of the groups who received vaccine showed signifi cantly higher incidence of mild or
moderate solicited adverse reactions than did the placebo group.
Interpretation The adenovirus 5-vectored Ebola vaccine of 1·6 × 10¹¹ viral particles was highly immunogenic and
safe. The lower dose of 4·0 × 10¹⁰ viral particles was also safe, but immunogenicity seemed to be more vulnerable
to the pre-existing immunity of adenovirus 5. A homologous priming-boosting regimen with adenovirus type-5
Ebola vaccine at 6 months interval was able to elicit greater antibody responses with longer duration. These results
support an immunisation strategy to implement a booster injection for a more durable protection against Ebola
virus disease
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