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To evaluate delivery management and outcomes in fetuses prenatally diagnosed with CHD.
A retrospective cohort study was conducted on 6194 fetuses (born between 2013 and 2016), comparing prenatally diagnosed with CHD (170) to those with non-cardiac (234) and no anomalies (5790). Primary outcomes included the incidence of preterm delivery and mode of delivery.
Gestational age at delivery was significantly lower between the CHD and non-anomalous cohorts (38.6 and 39.1 weeks, respectively). Neonates with CHD had a significantly lower birth weights (p < 0.001). There was an approximately 1.5-fold increase in the rate of primary cesarean sections associated with prenatally diagnosed CHD with an odds ratio of 1.49 (95% CI 1.06–2.10).
Our study provides additional evidence that the prenatal diagnosis of CHD is associated with a lower birth weight, preterm delivery, and with an increased risk of delivery by primary cesarean section.
The first positive genome-wide association study on gestational length and preterm delivery showed the involvement of an Se metabolism gene. In the present study, we examine the association between maternal intake of Se and Se status with gestational length and preterm delivery in 72 025 women with singleton live births from the population-based, prospective Norwegian Mother, Father and Child Cohort Study (MoBa). A self-reported, semi-quantitative FFQ answered in pregnancy week 22 was used to estimate Se intake during the first half of pregnancy. Associations were analysed with adjusted linear and Cox regressions. Se status was assessed in whole blood collected in gestational week 17 (n 2637). Median dietary Se intake was 53 (interquartile range (IQR) 44–62) µg/d, supplements provided additionally 50 (IQR 30–75) µg/d for supplement users (n 23 409). Maternal dietary Se intake was significantly associated with prolonged gestational length (β per sd = 0·25, 95 % CI, 0·07, 0·43) and decreased risk of preterm delivery (n 3618, hazard ratio per sd = 0·92, 95 % CI, 0·87, 0·98). Neither Se intake from supplements nor maternal blood Se status was associated with gestational length or preterm delivery. Hence, the present study showed that maternal dietary Se intake but not intake of Se-containing supplements, during the first half of pregnancy was significantly associated with decreased risk of preterm delivery. Further investigations, preferably in the form of a large randomised controlled trial, are needed to elucidate the impact of Se on pregnancy duration.
Food hubs are of interest in regional and local food system development because they potentially enhance the sustainability of food supply chains. Expanding on earlier literature, this study introduces economies of scale into an aggregation hub location model and disaggregates production into four seasons to account for geographic and seasonal variation of US fresh produce production. A mixed integer linear programming model is formulated with the objective of minimizing total costs of assembly and first-handler operations. Results suggest scale economies have significant effects on the optimal number, locations, and sizes of aggregation hubs. We model regional and local food systems in a manner more consistent with economic theory and provide a richer framework for policy analysis.
Background: Cerebral vasospasm is a leading cause of neurological disability following aneurysmal subarachnoid hemorrhage (aSAH). Clinical features associated with vasospasm development include blood burden on CT, neurological status, age and aneurysm location. Early cerebral CT perfusion (CTP) scanning in aSAH may be an independent predictor of vasospasm and/or delayed cerebral ischemia (DCI). Methods: Forty-one patients with aSAH were prospectively enrolled. Baseline data collected included WFNS grade, loss of consciousness at ictus, and modified Fisher grade. CTP was obtained at baseline and on day 6 post SAH. Cerebral blood volume, cerebral blood flow and mean transit time were measured. DCI was confirmed by a combination of clinical assessments, non-contrast CT and CTP. Radiological vasospasm was assessed with CT angiography. Results: Despite 80% of patients having a modified Fisher grade 3 or 4 aSAH, one-third presenting with ictal LOC and half having anterior communicating artery aneurysms, only one patient developed clinical evidence of vasospasm/DCI. Two others had asymptomatic radiological vasospasm. CTP parameters did not differ between groups defined by clinical predictors. Conclusions: In an unexpected finding, clinical and radiological vasospasm were very uncommon in this cohort. Clinical predictive variables correlated poorly with development of vasospasm. CTP may help refine the model but further work is needed.
Chitinase is responsible for insect chitin hydrolyzation, which is a key process in insect molting and pupation. However, little is known about the chitinase of Spodoptera exigua (SeChi). In this study, based on the SeChi gene (ADI24346) identified in our laboratory, we constructed the recombinant baculovirus P-Chi for the expression of recombinant SeChi (rSeChi) in Hi5 cells. The rSeChi was purified by chelate affinity chromatography, and the purified protein showed activity comparable with that of a commercial SgChi, suggesting that we harvested active SeChi for the first time. The purified protein was subsequently tested for enzymatic properties and revealed to exhibit its highest activity at pH 8 and 40 C. Using homology modeling and molecular docking techniques, the three-dimensional model of SeChi was constructed and screened for inhibitors. In two rounds of screening, twenty compounds were selected. With the purified rSeChi, we tested each of the twenty compounds for inhibitor activity against rSeChi, and seven compounds showed obvious activity. This study provided new information for the chitinase of beet armyworm and for chitinase inhibitor development.
Co-receptor tropism has been identified to correlate with HIV-1 transmission and the disease progression in patients. A molecular epidemiology investigation of co-receptor tropism is important for clinical practice and effective control of HIV-1. In this study, we investigated the co-receptor tropism on HIV-1 variants of 85 antiretroviral-naive patients with Geno2pheno algorithm at a false-positive rate of 10%. Our data showed that a majority of the subjects harboured the CCR5-tropic virus (81.2%, 69/85). No significant differences in gender, age, baseline CD4+ T-cell counts and transmission routes were observed between subjects infected with CXCR4-tropic or CCR5-tropic virus. The co-receptor tropism appeared to be associated with the virus genotype; a significantly more CXCR4-use was predicted in CRF01_AE infections whereas all CRF07_BC and CRF08_BC were predicted to use CCR5 co-receptor. Sequences analysis of V3 revealed a higher median net charge in the CXCR4 viruses over CCR5 viruses (4.0 vs. 3.0, P < 0.05). The predicted N-linked glycosylation site between amino acids 6 and 8 in the V3 region was conserved in CCR5 viruses, but not in CXCR4 viruses. Besides, variable crown motifs were observed in both CCR5 and CXCR4 viruses, of which the most prevalent motif GPGQ existed in both viral tropism and almost all genotypes identified in this study except subtype B. These findings may offer important implications for clinical practice and enhance our understanding of HIV-1 biology.
Background: Intracranial aneurysms are relatively common and often incidentally detected. Elective treatment may eliminate the risk of future hemorrhage, but carries risks of permanent deficit or death. Case-control studies have suggested factors predisposing to aneurysm rupture as well as risks of elective aneurysm repair. A clinical tool was recently developed to weigh benefits of repair against treatment risks. We evaluate its performance against real-world clinical decisions made by a cerebrovascular multidisciplinary team (MDT). Methods: Chart review of all patients with unruptured intracranial berry aneurysms (UIA) discussed at cerebrovascular MDT rounds 2008-2015. Management decisions and clinical outcomes were recorded. The Unruptured Intracranial Aneurysm Treatment Score (UIATS) was calculated for each patient (each aneurysm in the case of multiple UIA). Results: We identified 240 patients with a total of 279 aneurysms. UIATS recommended aneurysm repair in 79 cases, conservative management in 88 cases, and was equivocal in 112 cases. Where the UIATS gave a clear decision, that decision was concordant with the MDT decision in 119/167 cases (71%). Discordant decisions often related to the presence of comorbidities. Clinical outcomes did not differ in cases where the recommendations were clearly concordant vs. discordant. Conclusions: The UIATS may provide guidance to non-expert clinicians. It did not outperform the MDT.
Over the past 8 years, human enteroviruses (HEVs) have caused 27 227 cases of hand, foot and mouth disease (HFMD) in Xiamen, including 99 severe cases and six deaths. We aimed to explore the molecular epidemiology of HFMD in Xiamen to inform the development of diagnostic assays, vaccines and other interventions. From January 2009 to September 2015, 5866 samples from sentinel hospitals were tested using nested reverse transcription PCR that targeted the HEV 5′ untranslated region and viral protein 1 region. Of these samples, 4290 were tested positive for HEV and the amplicons were sequenced and genotyped. Twenty-two genotypes were identified. Enterovirus 71 (EV71) and coxsackieviruses A16, A6 and A10 (CA16, CA6 and CA10) were the most common genotypes, and there were no changes in the predominant lineages of these genotypes. EV71 became the most predominant genotype every 2 years. From 2013, CA6 replaced CA16 as one of the two most common genotypes. The results demonstrate the vast diversity of HFMD pathogens, and that minor genotypes are able to replace major genotypes. We recommend carrying-out long-term monitoring of the full spectrum of HFMD pathogens, which could facilitate epidemic prediction and the development of diagnostic assays and vaccines.
The pressure oscillation and terminal shock motion in a two dimensional inlet, which was designed for tandem configuration turbine-based combined cycle propulsion systems was investigated experimentally and numerically, respectively. The inlet was characterised by a bleed cavity upstream the inlet throat, an S-shape rectangular-to-circular diffuser and flowpaths for a turbine and a ramjet engine. The terminal shock motion was calculated through a second-order unsteady Reynolds-averaged Navier-Stokes scheme. The pressure and the terminal shock were unsteady when the combined cycle inlet operated at different conditions. With the terminal shock located in the throat and at the shoulder of the third ramp of the TBCC inlet, the pressure oscillation was significant and the shock exhibited unsteady streamwise motion with an oscillatory pattern. The amplitude of shock oscillation at these two conditions was 6mm and 12mm, respectively. When the shock was located downstream of the throat and upstream of the cowl lip, it oscillated in a small range. We defined this motion as the “shake” of the shock. This unsteady behaviour of the shock was caused by flow separation in the combined cycle inlet diffuser.
Human infection with the emerging avian influenza A(H7N9) virus in China in 2013 has raised global concerns. We conducted a retrospective descriptive study of 27 confirmed human influenza A(H7N9) cases in Jiangsu Province, to elaborate poultry-related exposures and to provide a more precise estimate of the incubation periods of the illness. The median incubation period was 6 days (range 2–10 days) in cases with single known exposure and was 7·5 days (range 6·5–12·5 days) in cases with exposures on multiple days, difference between the two groups was not significant (Z = −1·895, P = 0·058). The overall median incubation period for all patients was estimated to be 7·5 days (range 2–12·5 days). Our findings further highlight the necessity for public health authorities to extend the period of medical surveillance from 7 days to 10 days.
Strabismus represents a complex oculomotor disorder characterized by the deviation of one or both eyes and poor vision. A more sophisticated understanding of the genetic liability of strabismus is required to guide searches for associated molecular variants. In this classical twin study of 1,462 twin pairs, we examined the relative influence of genes and environment in comitant strabismus, and the degree to which these influences can be explained by factors in common with refractive error. Participants were examined for the presence of latent (‘phoria’) and manifest (‘tropia’) strabismus using cover–uncover and alternate cover tests. Two phenotypes were distinguished: eso-deviation (esophoria and esotropia) and exo-deviation (exophoria and exotropia). Structural equation modeling was subsequently employed to partition the observed phenotypic variation in the twin data into specific variance components. The prevalence of eso-deviation and exo-deviation was 8.6% and 20.7%, respectively. For eso-deviation, the polychoric correlation was significantly greater in monozygotic (MZ) (r = 0.65) compared to dizygotic (DZ) twin pairs (r = 0.33), suggesting a genetic role (p = .003). There was no significant difference in polychoric correlation between MZ (r = 0.55) and DZ twin pairs (r = 0.53) for exo-deviation (p = .86), implying that genetic factors do not play a significant role in the etiology of exo-deviation. The heritability of an eso-deviation was 0.64 (95% CI 0.50–0.75). The additive genetic correlation for eso-deviation and refractive error was 0.13 and the bivariate heritability (i.e., shared variance) was less than 1%, suggesting negligible shared genetic effect. This study documents a substantial heritability of 64% for eso-deviation, yet no corresponding heritability for exo-deviation, suggesting that the genetic contribution to strabismus may be specific to eso-deviation. Future studies are now needed to identify the genes associated with eso-deviation and unravel their mechanisms of action.
Samples of single-phase Sr2FeMoO6 were successfully prepared by solid-state reaction with long sintering times. The crystal structures of the Sr2FeMoO6 samples were determined from X-ray powder diffraction data using the Rietveld refinement method. The structure results obtained by the Rietveld refinements show that an increase in the total sintering time of the solid-state reaction is an effective method to obtain single Sr2FeMoO6 phase and to improve the ordering of Fe and Mo cations (or reducing antisite defects) in the double-perovskite structure. The volume of the tetragonal unit cell of Sr2FeMoO6 contracts slightly after successive sintering treatments. The averaged Fe-O and Mo-O bond lengths as well as the tilt between the FeO6 and the MoO6 octahedra decrease with increasing total sintering time. Our results suggest that the detected subtle changes in crystal structure, such as bond lengths and bond angles between the Fe and Mo cations and oxygen, in the ordered double-perovskite structure may be responsible for the large effects on previously reported transport and magnetic properties of an oxide metal.
Individual nanotubes made of carbon, boron nitride, iron, silicon, or other materials have properties such as high strength, toughness, electrical and thermal conductivity, and light weight that cannot be matched by conventional materials. Nanotubes also change their properties in response to external fields and change one type of energy into another, which are useful for design. This article explores three main steps in exploiting responsive materials based on nanotubes: nanotube synthesis, macroscale material fabrication, and incorporation into device structures for novel applications. Nanotubes are always synthesized as individual particles in the form of powders, smoke particles, or aligned forests. To be industrially important, nanotubes generally must be processed to form derivative materials such as functionalized/coated powders and forests and macroscale intermediate materials such as sheets, ribbon, and yarn. The processed nanotubes are then used to develop responsive materials and devices that are able to resist, react to, or generate energy from their environment. This article provides background information and ideas on how to develop nanotube responsive materials for everyday use.
The chemical regeneration method of human enamel was improved for the probable clinical application: an oral medical device was designed to significantly reduce the necessary amount of remineralization liquid; the reactive liquid phase system was redesigned, thus the solution could be stored for long time.