2,506 research outputs found

    Examination of Teacher Workplace Satisfaction and Student Achievement

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    Research has been conducted to study teacher workplace satisfaction. The following factors were identified as integral to teacher workplace satisfaction: administrative support; student behaviors; workplace atmosphere; autonomy and efficacy. Findings within the extant literature indicated that student achievement is a factor in teachers\u27 satisfaction with their work. Specifically, educators have repeatedly expressed a need to impact student achievement and have noted satisfaction or dissatisfaction in relation to their perception of their influence or lack therefore. The purpose of this study was to examine the relationship between teacher workplace satisfaction and student achievement with the intent of making recommendations regarding maximization of satisfaction in order to positively impact student achievement. A non-experimental design was used to examine teacher workplace satisfaction and student achievement. The researcher designed a teacher workplace satisfaction survey and distributed it to 1,532 teachers within a large metropolitan school district in Georgia to measure five factors of workplace satisfaction (administrative support, student behaviors, workplace atmosphere, autonomy, and efficacy). Further, student achievement data for each teacher participant was gathered. A mean scale score of student achievement scores for the students assigned to each teacher was calculated and matched with the corresponding teacher\u27s satisfaction rating. An independent t-test was conducted to determine whether or not teacher workplace satisfaction and student achievement had statistically significant different mean values. In order to discern the relationship between teacher workplace satisfaction and student achievement, the five factors (administrative support, student behaviors, workplace atmosphere, autonomy, and efficacy) that contribute to the dependent variable, student achievement, were held constant to estimate the independent contribution of each to the variation in student achievement. Through a multiple regression analysis, the findings of this study reaffirmed the correlation between satisfaction and student achievement, but they did not however, provide any additional insight for development of a predictive model because teacher satisfaction is a complex phenomenon made up of several factors that individually cannot account for improved student achievement. Thus, how best to maximize workplace satisfaction as a vehicle to improving student achievement remains unknown

    Characterization of an H4N2 influenza virus from Quails with a multibasic motif in the hemagglutinin cleavage site

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    AbstractThe cleavage motif in the hemagglutinin (HA) protein of highly pathogenic H5 and H7 subtypes of avian influenza viruses is characterized by a peptide insertion or a multibasic cleavage site (MBCS). Here, we isolated an H4N2 virus from quails (Quail/CA12) with two additional arginines in the HA cleavage site, PEKRRTR/G, forming an MBCS-like motif. Quail/CA12 is a reassortant virus with the HA and neuraminidase (NA) gene most similar to a duck-isolated H4N2 virus, PD/CA06 with a monobasic HA cleavage site. Quail/CA12 required exogenous trypsin for efficient growth in culture and caused no clinical illness in infected chickens. Quail/CA12 had high binding preference for α2,6-linked sialic acids and showed higher replication and transmission ability in chickens and quails than PD/CA06. Although the H4N2 virus remained low pathogenic, these data suggests that the acquisition of MBCS in the field is not restricted to H5 or H7 subtypes

    Gene Signatures Derived from a c-MET-Driven Liver Cancer Mouse Model Predict Survival of Patients with Hepatocellular Carcinoma

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    Biomarkers derived from gene expression profiling data may have a high false-positive rate and must be rigorously validated using independent clinical data sets, which are not always available. Although animal model systems could provide alternative data sets to formulate hypotheses and limit the number of signatures to be tested in clinical samples, the predictive power of such an approach is not yet proven. The present study aims to analyze the molecular signatures of liver cancer in a c-MET-transgenic mouse model and investigate its prognostic relevance to human hepatocellular carcinoma (HCC). Tissue samples were obtained from tumor (TU), adjacent non-tumor (AN) and distant normal (DN) liver in Tet-operator regulated (TRE) human c-MET transgenic mice (n = 21) as well as from a Chinese cohort of 272 HBV- and 9 HCV-associated HCC patients. Whole genome microarray expression profiling was conducted in Affymetrix gene expression chips, and prognostic significances of gene expression signatures were evaluated across the two species. Our data revealed parallels between mouse and human liver tumors, including down-regulation of metabolic pathways and up-regulation of cell cycle processes. The mouse tumors were most similar to a subset of patient samples characterized by activation of the Wnt pathway, but distinctive in the p53 pathway signals. Of potential clinical utility, we identified a set of genes that were down regulated in both mouse tumors and human HCC having significant predictive power on overall and disease-free survival, which were highly enriched for metabolic functions. In conclusions, this study provides evidence that a disease model can serve as a possible platform for generating hypotheses to be tested in human tissues and highlights an efficient method for generating biomarker signatures before extensive clinical trials have been initiated

    Exposure of Monocytic Cells to Lipopolysaccharide Induces Coordinated Endotoxin Tolerance, Mitochondrial Biogenesis, Mitophagy, and Antioxidant Defenses

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    In order to limit the adverse effects of excessive inflammation, anti-inflammatory responses are stimulated at an early stage of an infection, but during sepsis these can lead to deactivation of immune cells including monocytes. In addition, there is emerging evidence that the up-regulation of mitochondrial quality control mechanisms, including mitochondrial biogenesis and mitophagy, is important during the recovery from sepsis and inflammation. We aimed to describe the relationship between the compensatory immune and mitochondrial responses that are triggered following exposure to an inflammatory stimulus in human monocytic cells. Incubation with lipopolysaccharide resulted in a change in the immune phenotype of THP-1 cells consistent with the induction of endotoxin tolerance, similar to that seen in deactivated septic monocytes. After exposure to LPS there was also early evidence of oxidative stress, which resolved in association with the induction of antioxidant defenses and the stimulation of mitochondrial degradation through mitophagy. This was compensated by a parallel up-regulation of mitochondrial biogenesis that resulted in an overall increase in mitochondrial respiratory activity. These observations improve our understanding of the normal homeostatic responses that limit the adverse cellular effects of unregulated inflammation, and which may become ineffective when an infection causes sepsis

    Treating the placenta to prevent adverse effects of gestational hypoxia on fetal brain development.

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    Some neuropsychiatric disease, including schizophrenia, may originate during prenatal development, following periods of gestational hypoxia and placental oxidative stress. Here we investigated if gestational hypoxia promotes damaging secretions from the placenta that affect fetal development and whether a mitochondria-targeted antioxidant MitoQ might prevent this. Gestational hypoxia caused low birth-weight and changes in young adult offspring brain, mimicking those in human neuropsychiatric disease. Exposure of cultured neurons to fetal plasma or to secretions from the placenta or from model trophoblast barriers that had been exposed to altered oxygenation caused similar morphological changes. The secretions and plasma contained altered microRNAs whose targets were linked with changes in gene expression in the fetal brain and with human schizophrenia loci. Molecular and morphological changes in vivo and in vitro were prevented by a single dose of MitoQ bound to nanoparticles, which were shown to localise and prevent oxidative stress in the placenta but not in the fetus. We suggest the possibility of developing preventative treatments that target the placenta and not the fetus to reduce risk of psychiatric disease in later life

    Genome-wide association and HLA fine-mapping studies identify risk loci and genetic pathways underlying allergic rhinitis

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    Allergic rhinitis is the most common clinical presentation of allergy, affecting 400 million people worldwide, with increasing incidence in westernized countries1,2. To elucidate the genetic architecture and understand the underlying disease mechanisms, we carried out a meta-analysis of allergic rhinitis in 59,762 cases and 152,358 controls of European ancestry and identified a total of 41 risk loci for allergic rhinitis, including 20 loci not previously associated with allergic rhinitis, which were confirmed in a replication phase of 60,720 cases and 618,527 controls. Functional annotation implicated genes involved in various immune pathways, and fine mapping of the HLA region suggested amino acid variants important for antigen binding. We further performed genome-wide association study (GWAS) analyses of allergic sensitization against inhalant allergens and nonallergic rhinitis, which suggested shared genetic mechanisms across rhinitis-related traits. Future studies of the identified loci and genes might identify novel targets for treatment and prevention of allergic rhinitis

    Chronic kidney disease and arrhythmias: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference.

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    Patients with chronic kidney disease (CKD) are predisposed to heart rhythm disorders, including atrial fibrillation (AF)/atrial flutter, supraventricular tachycardias, ventricular arrhythmias, and sudden cardiac death (SCD). While treatment options, including drug, device, and procedural therapies, are available, their use in the setting of CKD is complex and limited. Patients with CKD and end-stage kidney disease (ESKD) have historically been under-represented or excluded from randomized trials of arrhythmia treatment strategies,1 although this situation is changing.2 Cardiovascular society consensus documents have recently identified evidence gaps for treating patients with CKD and heart rhythm disorders [...
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