•Inverse associations between chemical mixtures and child’s FIQ were observed.•Prenatal exposure to Pb and BPA were associated with decreased child’s FIQ.•Sex-stratified analyses showed stronger ...effects of chemical exposures in boys.•Integrating multiple statistical methods were beneficial to draw a more accurate conclusion.
Prenatal exposure to heavy metals, pesticides and phenols has been suggested to interfere with neurodevelopment, but the neurotoxicity of their mixtures is still unclear. We aimed to elucidate the associations of maternal urinary concentrations of selected chemical mixtures with intelligence quotient (IQ) in children.
Maternal urinary concentrations of selected heavy metals, pesticide metabolites, and phenols were quantified in pregnant women who participated in the Sheyang Mini Birth Cohort Study (SMBCS) from June 2009 to January 2010. At age 7 years, child’s IQ score was assessed using the Chinese version of Wechsler Intelligence Scale for Children (C-WISC) by trained pediatricians. Generalized linear regression models (GLM), Bayesian kernel machine regression (BKMR) models and elastic net regression (ENR) models were used to assess the associations of urinary concentrations individual chemicals and their mixtures with IQ scores of the 7-year-old children.
Of 326 mother-child pairs, single-chemical models indicated that prenatal urinary concentrations of lead (Pb) and bisphenol A (BPA) were significantly negatively associated with full intelligence quotient (FIQ) among children aged 7 years β = −2.31, 95% confidence interval (CI): −4.13, −0.48; p = 0.013, sex interaction p-value = 0.076; β = −1.18, 95% CI: −2.21, −0.15; p = 0.025; sex interaction p-value = 0.296, for Pb and BPA, respectively. Stratified analysis by sex indicated that the associations were only statistically significant in boys. In multi-chemical BKMR and ENR models, statistically significant inverse association was found between prenatal urinary Pb level and boy’s FIQ scores at 7 years. Furthermore, BKMR analysis indicated that the overall mixture was associated with decreases in boy’s IQ when all the chemicals’ concentrations were at their 75th percentiles or higher, compared to at their 50th percentiles. ENR models revealed that maternal urinary Pb levels were statistically significantly associated with lower FIQ scores (β = −2.20, 95% CI: −4.20, −0.20; p = 0.031).
Prenatal exposure to selected chemical mixtures may affect intellectual performance at 7 years of age, particularly in boys. Pb and BPA were suspected as primary chemicals associated with child neurodevelopment.
The aim of this study was to investigate the repair effect of human acellular amniotic membrane (HAAM) loading bone marrow mesenchymal stem cells (BMSCs) on articular cartilage defect in rabbits. ...Rabbit BMSCs were isolated and cultured, and they were then inoculated on HAAM to prepare the complex of HAAM and BMSCs. Twenty-four rabbits were randomly divided into groups A and B, with 12 animals in each group. The left and right sides were used as the experimental and control sides, respectively. The models of bilateral articular cartilage defect were established. The defect areas on the experimental side in groups A and B were implanted with the complex of HAAM and BMSCs and HAAM alone, respectively. The control sides of the two groups were not implanted with any material. In the 8th and 12th week after surgery, gross observation, histological examination and cartilage defect scoring were performed. In the 8th and 12th postoperative week, gross observation and histological observation showed that dense cartilage-like cells appeared in group A but not in group B, indicating preferable cartilage repair. The cartilage defect score on the experimental side in group A was 5.31 ± 0.68 in the 8th week and 3.23 ± 0.52 in the 12th week, and that in group A was significantly lower than in group B (P < 0.05). HAAM loading BMSCs has a good repair effect on articular cartilage defect under an in vitro environment.
We report the first measurements of absolute branching fractions for the W-exchange-only processes and with the double-tag technique, by analyzing an collision data sample, that corresponds to an ...integrated luminosity of 567 pb-1 collected at a center-of-mass energy of 4.6 GeV by the BESIII detector. The branching fractions are measured to be and , where the first uncertainties are statistical and the second systematic. Our results are more precise than the previous relative measurements.
Membrane proteins are generally classified into the following five types: (1) type I membrane proteins, (2) type II membrane proteins, (3) multipass transmembrane proteins, (4) lipid chain-anchored ...membrane proteins and (5) GPI-anchored membrane proteins. Prediction of membrane protein types has become one of the growing hot topics in bioinformatics. Currently, we are facing two critical challenges in this area: first, how to take into account the extremely complicated sequence-order effects, and second, how to deal with the highly uneven sizes of the subsets in a training dataset. In this paper, stimulated by the concept of using the pseudo-amino acid composition to incorporate the sequence-order effects, the spectral analysis technique is introduced to represent the statistical sample of a protein. Based on such a framework, the weighted support vector machine (SVM) algorithm is applied. The new approach has remarkable power in dealing with the bias caused by the situation when one subset in the training dataset contains many more samples than the other. The new method is particularly useful when our focus is aimed at proteins belonging to small subsets. The results obtained by the self-consistency test, jackknife test and independent dataset test are encouraging, indicating that the current approach may serve as a powerful complementary tool to other existing methods for predicting the types of membrane proteins.
Using a data set with an integrated luminosity of 2.93 fb(-1) collected at root s = 3.773 GeV with the BESIII detector operating at the BEPCII storage rings, we search for the rare decay D+ -> ...D(0)e(+)nu(e). No signal events are observed. We set the upper limit on the branching fraction for D+ -> D(0)e(+)nu(e) to be 1.0 x 10(-4) at the 90% confidence level.
Background Human reproduction depends on the fusion of a mature oocyte with a sperm cell to form a fertilized egg. The genetic events that lead to the arrest of human oocyte maturation are unknown. ...Methods We sequenced the exomes of five members of a four-generation family, three of whom had infertility due to oocyte meiosis I arrest. We performed Sanger sequencing of a candidate gene, TUBB8, in DNA samples from these members, additional family members, and members of 23 other affected families. The expression of TUBB8 and all other β-tubulin isotypes was assessed in human oocytes, early embryos, sperm cells, and several somatic tissues by means of a quantitative reverse-transcriptase-polymerase-chain-reaction assay. We evaluated the effect of the TUBB8 mutations on the assembly of the heterodimer consisting of one α-tubulin polypeptide and one β-tubulin polypeptide (α/β-tubulin heterodimer) in vitro, on microtubule architecture in HeLa cells, on microtubule dynamics in yeast cells, and on spindle assembly in mouse and human oocytes. Results We identified seven mutations in the primate-specific gene TUBB8 that were responsible for oocyte meiosis I arrest in 7 of the 24 families. TUBB8 expression is unique to oocytes and the early embryo, in which this gene accounts for almost all the expressed β-tubulin. The mutations affect chaperone-dependent folding and assembly of the α/β-tubulin heterodimer, disrupt microtubule behavior on expression in cultured cells, alter microtubule dynamics in vivo, and cause catastrophic spindle-assembly defects and maturation arrest on expression in mouse and human oocytes. Conclusions TUBB8 mutations have dominant-negative effects that disrupt microtubule behavior and oocyte meiotic spindle assembly and maturation, causing female infertility. (Funded by the National Basic Research Program of China and others.).
Two kinds of Ni-based superalloy powders (P-powder and A-powder) were prepared from masteralloy melted via the process of vacuum induction melting (VIM) by plasma rotating electrode process (PREP) ...and argon atomization (AA) method, which were used to fabricate two different alloys (P-alloy and A-alloy) using the same hot isostatic pressing process and heat treatment process. The study of microstructure and mechanical properties of FGH97 alloy were conducted to demonstrate the effect of different routes of powders preparation on the microstructure and low-cycle fatigue properties. Results show that the particle size distribution of P-powder is narrower than A-powder, and overall is larger, and the size of the inclusions in the A-powder is much smaller than P-powder. And it has been found that the grain size of A-alloy is finer and γ' phase is more uniform, compared with P-alloy, there is no residual dendrite, grain boundary carbides are intermittent punctate distribution; the strength of A-alloy is slightly higher, and the plasticity is better than P-alloy; at the same time, the crack initiation is formed at the site of slag inclusions, but the size of inclusions of A-alloy significantly smaller; accordingly, the resistance of low-cycle fatigue crack initiation of A-alloy is superior than that of P-alloy due to the fine powder prepared by the process of argon atomization, showing a life time of much more than 150 000 cycles, far better than P-alloy (<70000 cycles); and the fatigue property of A-alloy is very stable.
Aims: Fungal infection is still a life‐threatening risk for the immunocompromised population such as AIDS patients and those who receive treatments with immunosuppressors and/or frequent ...administrations of wide‐spectrum antibiotics, which inevitably lead to the drug resistance and unbalanced microflora populations. The present work was accordingly performed to characterize more potent antifungal metabolites from various cultures of marine fungi residing in white croaker Argyrosomus argentatus.
Methods and Results: The three most common opportunistic human pathogens Candida albicans (CCCCM ID 00148), Aspergillus niger (CCCCM ACCC 30005) and Trichophyton rubrum (CCCCM ID 00001) were selected as test fungi. A total of 16 cultivable fungal strains were isolated from the variant tissues of Ar. argentatus collected from the Yellow Sea, followed by preliminary antifungal screenings of the EtOAc extracts of the corresponding cultures. As a result, the inhibition of the three target fungi, plus being allergic to isolators’ skin, were discerned with the EtOAc extract of the fungus under the isolation number Z16 that was identified subsequently as Myrothecium sp. by a combination of morphological and 18S rDNA finger‐typing characteristics. A follow‐up bioassay fractionation of the EtOAc extract, in conjunction with spectral analyses MS, 1H‐NMR, 13C‐NMR, distortionless enhancement by polarization transfer (DEPT), heteronuclear multiple quantum coherence (HMQC) and heteronuclear multiple bond resonance (HMBC) wherever required, afforded eventually the characterization of a new acid (compound 1: 4,5‐ditridecyl‐octanedioic acid), three macrocyclic trichothecenes including roridin A (compound 2), verrucarin A (compound 3) and 8β‐acetoxy‐roridin H (compound 4), (22E,24R)‐cerevisterol (compound 5) and N‐phenyl‐β‐amino‐naphthalene (compound 6). In vitro antifungal tests showed that the three trichothecenes were active against A. niger, T. rubrum and C. albicans with MICs of 31·25, 62·5 and 125 μg ml−1 for compound 2, 250, 125 and 31·25 μg ml−1 for compound 3 as well as 125, 62·5 and 125 μg ml−1 for compound 4 respectively. The MICs of ketoconazole (co‐assayed herewith as a positive reference) against A. niger, T. rubrum and C. albicans were 31·25, 250, 31·25 μg ml−1 respectively. A preliminary structure–activity relationship of the antifungal trichothecenes was highlighted in brief.
Conclusions: The present investigation demonstrated that marine fungus Myrothecium sp. Z16 associated with white croaker (Ar. argentatus), was an efficient producer of a new acid and antifungal trichothecenes, the latter presumably being also the allergic substances in the culture.
Significance and Impact of the Study: The title marine fungus was investigated to be a resource of new aliphatic acid, and trichothecenes with potent antifungal and dermal toxic actions.
We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with ...the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3} eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3} eV^{2} for the inverted mass ordering.
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