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961.

Background

Cerebral palsy (CP) has a multifactorial etiology, and placental vascular disease may be one major risk factor. The risk of placental vascular disease may be lower among some immigrant groups. We studied the association between immigrant status and the risk of CP.

Methods

We conducted a population-based retrospective cohort study of all singleton and twin livebirths in Ontario between 2002–2008, and who survived ≥28 days after birth. Each child was assessed for CP up to age 4 years, based on either a single inpatient or ≥2 outpatient pediatric diagnoses of CP. Relative to non-immigrants (n = 566,668), the risk of CP was assessed for all immigrants (n = 177,390), and further evaluated by World region of origin. Cox proportional hazard ratios (aHR) were adjusted for maternal age, income, diabetes mellitus, obesity, tobacco use, Caesarean delivery, year of delivery, physician visits, twin pregnancy, preterm delivery, as well as small- and large-for-gestational age birthweight.

Results

There were 1346 cases of CP, with a lower rate among immigrants (1.45 per 1000) than non-immigrants (1.92 per 1000) (aHR 0.77, 95% confidence interval [CI] 0.67 to 0.88). Mothers from East Asia and the Pacific (aHR 0.54, 95% CI 0.39 to 0.77) and the Caribbean (aHR 0.58, 95% CI 0.37 to 0.93) were at a significantly lower risk of having a child with CP. Whether further adjusting for preeclampsia, gestational hypertension, placental abruption or placental infraction, or upon using a competing risk analysis that further accounted for stillbirth and neonatal death, these results did not change.

Conclusions

Immigration and ethnicity appear to attenuate the risk of CP, and this effect is not fully explained by known risk factors.  相似文献   
962.

Background

The p value obtained from a significance test provides no information about the magnitude or importance of the underlying phenomenon. Therefore, additional reporting of effect size is often recommended. Effect sizes are theoretically independent from sample size. Yet this may not hold true empirically: non-independence could indicate publication bias.

Methods

We investigate whether effect size is independent from sample size in psychological research. We randomly sampled 1,000 psychological articles from all areas of psychological research. We extracted p values, effect sizes, and sample sizes of all empirical papers, and calculated the correlation between effect size and sample size, and investigated the distribution of p values.

Results

We found a negative correlation of r = −.45 [95% CI: −.53; −.35] between effect size and sample size. In addition, we found an inordinately high number of p values just passing the boundary of significance. Additional data showed that neither implicit nor explicit power analysis could account for this pattern of findings.

Conclusion

The negative correlation between effect size and samples size, and the biased distribution of p values indicate pervasive publication bias in the entire field of psychology.  相似文献   
963.
964.
For subunit vaccines, adjuvants play a key role in shaping the magnitude, persistence and form of targeted antigen-specific immune response. Flagellin is a potent immune activator by bridging innate inflammatory responses and adaptive immunity and an adjuvant candidate for clinical application. Calcium phosphate nanoparticles are efficient carriers for different biomolecules like DNA, RNA, peptides and proteins. Flagellin-functionalized calcium phosphate nanoparticles were prepared and their immunostimulatory effect on the innate immune system, i.e. the cytokine production, was studied. They induced the production of the proinflammatory cytokines IL-8 (Caco-2 cells) and IL-1β (bone marrow-derived macrophages; BMDM) in vitro and IL-6 in vivo after intraperitoneal injection in mice. The immunostimulation was more pronounced than with free flagellin.  相似文献   
965.

Background

Acute respiratory infections (ARIs) are a major cause of morbidity and mortality in children in Africa. The circulation of viruses classically implicated in ARIs is poorly known in Burkina Faso. The aim of this study was to identify the respiratory viruses present in children admitted to or consulting at the pediatric hospital in Ouagadougou.

Methods

From July 2010 to July 2011, we tested nasal aspirates of 209 children with upper or lower respiratory infection for main respiratory viruses (respiratory syncytial virus (RSV), metapneumovirus, adenovirus, parainfluenza viruses 1, 2 and 3, influenza A, B and C, rhinovirus/enterovirus), by immunofluorescence locally in Ouagadougou, and by PCR in France. Bacteria have also been investigated in 97 samples.

Results

153 children (73.2%) carried at least one virus and 175 viruses were detected. Rhinoviruses/enteroviruses were most frequently detected (rhinovirus n = 88; enterovirus n = 38) and were found to circulate throughout the year. An epidemic of RSV infections (n = 25) was identified in September/October, followed by an epidemic of influenza virus (n = 13), mostly H1N1pdm09. This epidemic occurred during the period of the year in which nighttime temperatures and humidity were at their lowest. Other viruses tested were detected only sporadically. Twenty-two viral co-infections were observed. Bacteria were detected in 29/97 samples with 22 viral/bacterial co-infections.

Conclusions

This study, the first of its type in Burkina Faso, warrants further investigation to confirm the seasonality of RSV infection and to improve local diagnosis of influenza. The long-term objective is to optimize therapeutic management of infected children.  相似文献   
966.
Accurate segregation of chromosomes is critical to ensure that each daughter cell receives the full genetic complement. Maintenance of cohesion between sister chromatids, especially at centromeres, is required to segregate chromosomes precisely during mitosis and meiosis. The Drosophila protein MEI-S332, the founding member of a conserved protein family, is essential in meiosis for maintaining cohesion at centromeres until sister chromatids separate at the metaphase II/anaphase II transition. MEI-S332 localizes onto centromeres in prometaphase of mitosis or meiosis I, remaining until sister chromatids segregate. We elucidated a mechanism for controlling release of MEI-S332 from centromeres via phosphorylation by POLO kinase. We demonstrate that POLO antagonizes MEI-S332 cohesive function and that full POLO activity is needed to remove MEI-S332 from centromeres, yet this delocalization is not required for sister chromatid separation. POLO phosphorylates MEI-S332 in vitro, POLO and MEI-S332 bind each other, and mutation of POLO binding sites prevents MEI-S332 dissociation from centromeres.  相似文献   
967.
Hepatoma cell lines serve as a suitable model to study hepatic clearance of lipoprotein-associated cholesteryl esters (CEs). The present study aimed at investigating holoparticle-association of and selective CE-uptake from human high density lipoprotein subclass 3 (HDL3) by non-malignant adult (Chang-liver) and non-malignant fetal (WRL-68) epithelial cell lines as well as a hepatocellular carcinoma (HUH-7) cell line. Binding properties of 125I-HDL3 at 4 and 37 degrees C were similar for all three cell lines while degradation rates were highest for Chang-liver cells. Calculating the selective uptake of HDL3-associated CEs as the difference between [3H]CE- and 125I-HDL3 cell-association revealed that the selective lipid uptake and holoparticle-association was similar in Chang-liver while in WRL-68 and HUH-7 cells pronounced capacity for lipid tracer uptake in excess of holoparticle uptake was measured. Using RT-PCR, Northern and Western blot analysis, as well as immunocytochemical technique pronounced expression of scavenger receptor class B, type I (SR-BI) but not SR-BII (a splice variant of SR-BI less efficient for selective CE-uptake than SR-BI) could be identified in HUH-7 and WRL-68 cells. A polyclonal antiserum raised against SR-BI significantly decreased cell-association of [3H]CE-HDL3 in HUH-7 and WRL-68. The present findings suggest that the capacity for selective cholesteryl ester-uptake from high density lipoprotein by malignant and normal epithelial cells from the liver depends on expression of the scavenger receptor class B, type I.  相似文献   
968.
A variety of water-soluble prodrugs of BMS-191011 was synthesized and evaluated for solution state stability and rate of conversion to BMS-191011 in rat and human plasma. The deoxycarnitine ester prodrug (11c) was selected for clinical evaluation based on its superior chemical stability, crystallinity and cleavage to BMS-191011 in human plasma.  相似文献   
969.
A tight spatial-temporal coordination of F-actin dynamics is crucial for a large variety of cellular processes that shape cells. The Abelson interactor (Abi) has a conserved role in Arp2/3-dependent actin polymerization, regulating Wiskott-Aldrich syndrome protein (WASP) and WASP family verprolin-homologous protein (WAVE). In this paper, we report that Abi exerts nonautonomous control of photoreceptor axon targeting in the Drosophila visual system through WAVE. In abi mutants, WAVE is unstable but restored by reexpression of Abi, confirming that Abi controls the integrity of the WAVE complex in vivo. Remarkably, expression of a membrane-tethered WAVE protein rescues the axonal projection defects of abi mutants in the absence of the other subunits of the WAVE complex, whereas cytoplasmic WAVE only slightly affects the abi mutant phenotype. Thus complex formation not only stabilizes WAVE, but also provides further membrane-recruiting signals, resulting in an activation of WAVE.  相似文献   
970.
Cancellariidae, or nutmeg shells, is a family of marine gastropods that feed on the body fluids and the egg cases of marine animals. The 300 or so living species are distributed worldwide, mostly on soft bottoms, from intertidal to depths of about 1000 m. Although they are a key group for the understanding of neogastropod evolution, they are still poorly known in terms of anatomy, ecology and systematics. This paper reports the first mitochondrial multi-gene phylogenetic hypothesis for the group. Data were collected for 50 morphospecies, representative of 22 genera belonging to the three currently recognized subfamilies. Sequences from three genes (12S, 16S and COI) were analyzed with Maximum Likelihood analysis and Bayesian Inference, both as single gene datasets and in two partitioned concatenated alignment. Largely consistent topologies were obtained and discussed with respect to the traditional subfamilial arrangements. The obtained phylogenetic trees were also used to produce Robinson-Foulds supertrees. Our results confirmed the monophyly of the subfamily Plesiotritoninae, while Admetinae and Cancellariinae, as currently conceived, were retrieved as polyphyletic. Based on our findings we propose changes to the systematic arrangement of these subfamilies. At a lower taxonomic rank, our results highlighted the rampant homoplasy of many characters traditionally used to segregate genera, and thus the need of a critical re-evaluation of the contents of many genera (e.g. Nipponaphera, Merica, Sydaphera, Bivetia), the monophyly of which was not recovered.  相似文献   
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