410 research outputs found

    National curriculum policy in Norway and Brazil: translations of the global accountability logic

    Get PDF
    This paper addressed in what ways national curriculum policy in Norway and Brazil adopted the global accountability logic of which OECD and other international organizations are proponents. It borrowed from an institutional logics perspective to explain the complexity found within the accountability logic across these two nation-states. The method used was thematic analysis of the national curriculum policy. The findings revealed that national curriculum policy is informed by the international context, but translated within national contexts. Norway elaborated the accountability logic to encompass multiple aspects of this logic that reinforced each other to create a cohesive policy. In Brazil, tensions between different social groups resulted in a curriculum policy with contradictory aspects of the accountability logic. The translations of the global accountability logic reflected the context-specific features of each country and illustrated both homogeneity and heterogeneity that still exists in different educational contexts.publishedVersio

    National curriculum policy in Norway and Brazil Translations of the global accountability logic

    Get PDF
    This paper addressedin what ways national curriculum policy in Norway and Brazil adoptedthe global accountability logic of which OECD and other international organizations are proponents. It borrowedfrom an institutional logics perspective to explain the complexity found within the accountability logic across these two nation-states. The method used was thematic analysis of the national curriculum policy. The findings revealed that national curriculum policy is informed by the international context, but translated within national contexts. Norway elaborated the accountability logicto encompass multiple aspects of thislogic that reinforced each other to create a cohesive policy. In Brazil, tensions between different social groups resulted in a curriculum policy with contradictory aspects of the accountability logic. The translations of the global accountability logic reflected the context-specific features of each country andillustratedboth homogeneity and heterogeneity that still exists in different educational contexts.publishedVersio

    Polo-like kinase 4 controls centriole duplication but does not directly regulate cytokinesis.

    Get PDF
    Centrioles organize the centrosome, and accurate control of their number is critical for the maintenance of genomic integrity. Centrioles duplicate once per cell cycle, and duplication is coordinated by Polo-like kinase 4 (Plk4). We previously demonstrated that Plk4 accumulation is autoregulated by its own kinase activity. However, loss of heterozygosity of Plk4 in mouse embryonic fibroblasts has been proposed to cause cytokinesis failure as a primary event, leading to centrosome amplification and gross chromosomal abnormalities. Using targeted gene disruption, we show that human epithelial cells with one inactivated Plk4 allele undergo neither cytokinesis failure nor increase in centrosome amplification. Plk4 is shown to localize exclusively at the centrosome, with none in the spindle midbody. Substantial depletion of Plk4 by small interfering RNA leads to loss of centrioles and subsequent spindle defects that lead to a modest increase in the rate of cytokinesis failure. Therefore, Plk4 is a centriole-localized kinase that does not directly regulate cytokinesis

    A two-step strategy for the complementation of M. tuberculosis mutants

    Get PDF
    The sequence of Mycobacterium tuberculosis, completed in 1998, facilitated both the development of genomic tools, and the creation of a number of mycobacterial mutants. These mutants have a wide range of phenotypes, from attenuated to hypervirulent strains. These phenotypes must be confirmed, to rule out possible secondary mutations that may arise during the generation of mutant strains. This may occur during the amplification of target genes or during the generation of the mutation, thus constructing a complementation strain, which expresses the wild-type copy of the gene in the mutant strain, becomes necessary. In this study we have introduced a two-step strategy to construct complementation strains using the Ag85 promoter. We have constitutively expressed dosR and have shown dosR expression is restored to wild-type level

    Mycobacterium tuberculosis acg Gene Is Required for Growth and Virulence In Vivo

    Get PDF
    Mycobacterium tuberculosis dosRS two-component regulatory system controls transcription of approximately 50 genes including hspX, acg and Rv2030c, in response to hypoxia and nitric oxide conditions and within macrophages and mice. The hspX lies between acg and Rv2030c. However, the functions of the dosR regulated genes in vitro and in vivo are largely unknown. Previously, we demonstrated that deletion of hspX gene produced a mutant which grew faster in macrophages and in mice. In this study, we attempted to determine the functions of acg and Rv2030c by gene inactivation. We demonstrate that Rv2030c is dispensable for virulence and growth. However, deletion of acg produced a mutant which is attenuated in both resting and activated macrophages and in acute and persistent murine infection models. Surprisingly, deletion of acg did not compromise the viability of the mutant to nitrosative and oxidative stresses in vitro and in vivo. In addition, when the WT and the acg mutants were treated with antibiotics such as the prodrugs nitrofurantoin and nitrofuran, the acg mutant became more sensitive than the WT strain to these drugs. This suggests that Acg may not function as a nitroreductase. These data indicate that acg encodes an essential virulence factor for M. tuberculosis and enables it to grow and survive in macrophages and in mouse organs

    Acute and Persistent Mycobacterium tuberculosis Infections Depend on the Thiol Peroxidase TPX

    Get PDF
    The macrophage is the natural niche of Mycobacterium tuberculosis infection. In order to combat oxidative and nitrosative stresses and persist in macrophages successfully, M. tuberculosis is endowed with a very efficient antioxidant complex. Amongst these antioxidant enzymes, TpX is the only one in M. tuberculosis with sequence homology to thiol peroxidase. Previous reports have demonstrated that the M. tuberculosis TpX protein functions as a peroxidase in vitro. It is the dominant antioxidant which protects M. tuberculosis against oxidative and nitrosative stresses. The level of the protein increases in oxidative stress. To determine the roles of tpx gene in M. tuberculosis survival and virulence in vivo, we constructed an M. tuberculosis strain lacking the gene. The characteristics of the mutant were examined in an in vitro stationary phase model, in response to stresses; in murine bone marrow derived macrophages and in an acute and an immune resistant model of murine tuberculosis. The tpx mutant became sensitive to H2O2 and NO compared to the wild type strain. Enzymatic analysis using bacterial extracts from the WT and the tpx mutant demonstrated that the mutant contains reduced peroxidase activity. As a result of this, the mutant failed to grow and survive in macrophages. The growth deficiency in macrophages became more pronounced after interferon-Ξ³ activation. In contrast, its growth was significantly restored in the macrophages of inducible nitric oxide synthase (iNOS or NOS2) knockout mice. Moreover, the tpx mutant was impaired in its ability to initiate an acute infection and to maintain a persistent infection. Its virulence was attenuated. Our results demonstrated that tpx is required for M. tuberculosis to deal with oxidative and nitrosative stresses, to survive in macrophages and to establish acute and persistent infections in animal tuberculosis models

    Lack of effect of lowering LDL cholesterol on cancer: meta-analysis of individual data from 175,000 people in 27 randomised trials of statin therapy

    Get PDF
    <p>Background: Statin therapy reduces the risk of occlusive vascular events, but uncertainty remains about potential effects on cancer. We sought to provide a detailed assessment of any effects on cancer of lowering LDL cholesterol (LDL-C) with a statin using individual patient records from 175,000 patients in 27 large-scale statin trials.</p> <p>Methods and Findings: Individual records of 134,537 participants in 22 randomised trials of statin versus control (median duration 4.8 years) and 39,612 participants in 5 trials of more intensive versus less intensive statin therapy (median duration 5.1 years) were obtained. Reducing LDL-C with a statin for about 5 years had no effect on newly diagnosed cancer or on death from such cancers in either the trials of statin versus control (cancer incidence: 3755 [1.4% per year [py]] versus 3738 [1.4% py], RR 1.00 [95% CI 0.96-1.05]; cancer mortality: 1365 [0.5% py] versus 1358 [0.5% py], RR 1.00 [95% CI 0.93–1.08]) or in the trials of more versus less statin (cancer incidence: 1466 [1.6% py] vs 1472 [1.6% py], RR 1.00 [95% CI 0.93–1.07]; cancer mortality: 447 [0.5% py] versus 481 [0.5% py], RR 0.93 [95% CI 0.82–1.06]). Moreover, there was no evidence of any effect of reducing LDL-C with statin therapy on cancer incidence or mortality at any of 23 individual categories of sites, with increasing years of treatment, for any individual statin, or in any given subgroup. In particular, among individuals with low baseline LDL-C (<2 mmol/L), there was no evidence that further LDL-C reduction (from about 1.7 to 1.3 mmol/L) increased cancer risk (381 [1.6% py] versus 408 [1.7% py]; RR 0.92 [99% CI 0.76–1.10]).</p> <p>Conclusions: In 27 randomised trials, a median of five years of statin therapy had no effect on the incidence of, or mortality from, any type of cancer (or the aggregate of all cancer).</p&gt

    Disparities and risks of sexually transmissible infections among men who have sex with men in China: a meta-analysis and data synthesis.

    Get PDF
    BACKGROUND: Sexually transmitted infections (STIs), including Hepatitis B and C virus, are emerging public health risks in China, especially among men who have sex with men (MSM). This study aims to assess the magnitude and risks of STIs among Chinese MSM. METHODS: Chinese and English peer-reviewed articles were searched in five electronic databases from January 2000 to February 2013. Pooled prevalence estimates for each STI infection were calculated using meta-analysis. Infection risks of STIs in MSM, HIV-positive MSM and male sex workers (MSW) were obtained. This review followed the PRISMA guidelines and was registered in PROSPERO. RESULTS: Eighty-eight articles (11 in English and 77 in Chinese) investigating 35,203 MSM in 28 provinces were included in this review. The prevalence levels of STIs among MSM were 6.3% (95% CI: 3.5-11.0%) for chlamydia, 1.5% (0.7-2.9%) for genital wart, 1.9% (1.3-2.7%) for gonorrhoea, 8.9% (7.8-10.2%) for hepatitis B (HBV), 1.2% (1.0-1.6%) for hepatitis C (HCV), 66.3% (57.4-74.1%) for human papillomavirus (HPV), 10.6% (6.2-17.6%) for herpes simplex virus (HSV-2) and 4.3% (3.2-5.8%) for Ureaplasma urealyticum. HIV-positive MSM have consistently higher odds of all these infections than the broader MSM population. As a subgroup of MSM, MSW were 2.5 (1.4-4.7), 5.7 (2.7-12.3), and 2.2 (1.4-3.7) times more likely to be infected with chlamydia, gonorrhoea and HCV than the broader MSM population, respectively. CONCLUSION: Prevalence levels of STIs among MSW were significantly higher than the broader MSM population. Co-infection of HIV and STIs were prevalent among Chinese MSM. Integration of HIV and STIs healthcare and surveillance systems is essential in providing effective HIV/STIs preventive measures and treatments. TRIAL REGISTRATION: PROSPERO NO: CRD42013003721

    An association between unrecognized gastroesophageal reflux disease and excessive daytime sleepiness in Taiwanese subjects suspected to have liver disease: a pilot study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>In traditional Chinese culture, liver disease is believed to underlie excessive daytime sleepiness (EDS). Consequently, Chinese patients with complaints of EDS and physicians who treat them suspect that a liver abnormality is present. If liver disease is ruled out, these patients are often discharged without treatment. Gastroesophageal reflux disease (GERD) is a common disorder also associated with EDS. This pilot study was undertaken to determine the prevalence of GERD among Taiwanese patients with complaints of EDS suspected to be related to liver disease but in whom no evidence for the latter was found.</p> <p>Methods</p> <p>From July 2009 to December 2009, 121 outpatients who presented to or were referred to the Department of Gastroenterology and Hepatology of the Chiayi Gung Memorial Hospital for evaluation of a complaint of EDS thought to be due to liver disease were examined. Demographic data were collected, and physical examinations and liver function tests were performed. Forty-eight patients had liver disease and were excluded. The Chinese Epworth Sleepiness Scale questionnaire (Chinese ESS) and the Chinese Gastroesophageal Reflux Disease Questionnaire (CGERDQ) were then administered to 73 included patients.</p> <p>Results</p> <p>More than half (56.2%) of the included patients were found to suffer from GERD. Patients with symptoms of GERD had higher mean CGERDQ scores than patients without symptoms of the disorder (18.88 Β± 5.49 and 5.56 Β± 3.57, respectively; <it>P </it>< 0.001). Patients with symptoms of GERD also had higher mean Chinese ESS scores than patients without symptoms (8.80 Β± 5.49 and 3.13 Β± 3.50, respectively; <it>P </it>< 0.001). Chinese ESS scores indicative of EDS were observed in 48.8% of patients with symptoms of GERD and in 3.1% of those without symptoms (<it>P </it>< 0.001). Differences between the two groups retained their significance after controlling for potential confounders.</p> <p>Conclusions</p> <p>A significant percentage of Taiwanese patients who complained of EDS and were admitted to our Hepatology/Gastroenterology Department due to a suspicion of liver disease actually had symptoms of GERD. Further studies are needed to ascertain whether treatment of GERD will effectively resolve EDS in these patients.</p
    • …
    corecore