197 research outputs found

    Patent Foramen Ovale, Ischemic Stroke and Migraine: Systematic Review and Stratified Meta-Analysis of Association Studies

    Get PDF
    BACKGROUND: Observational data have reported associations between patent foramen ovale (PFO), cryptogenic stroke and migraine. However, randomized trials of PFO closure do not demonstrate a clear benefit either because the underlying association is weaker than previously suggested or because the trials were underpowered. In order to resolve the apparent discrepancy between observational data and randomized trials, we investigated associations between (1) migraine and ischemic stroke, (2) PFO and ischemic stroke, and (3) PFO and migraine. METHODS: Eligibility criteria were consistent; including all studies with specifically defined exposures and outcomes unrestricted by language. We focused on studies at lowest risk of bias by stratifying analyses based on methodological design and quantified associations using fixed-effects meta-analysis models. RESULTS: We included 37 studies of 7,686 identified. Compared to reports in the literature as a whole, studies with population-based comparators showed weaker associations between migraine with aura and cryptogenic ischemic stroke in younger women (OR 1.4; 95% CI 0.9–2.0; 1 study), PFO and ischemic stroke (HR 1.6; 95 CI 1.0–2.5; 2 studies; OR 1.3; 95% CI 0.9–1.9; 3 studies), or PFO and migraine (OR 1.0; 95% CI 0.6–1.6; 1 study). It was not possible to look for interactions or effect modifiers. These results are limited by sources of bias within individual studies. CONCLUSIONS: The overall pairwise associations between PFO, cryptogenic ischemic stroke and migraine do not strongly suggest a causal role for PFO. Ongoing randomized trials of PFO closure may need larger numbers of participants to detect an overall beneficial effect

    Perinatal HIV infection is associated with deficits in muscle function in children and adolescents:a cross-sectional study in Zimbabwe

    Get PDF
    Objectives: To determine how muscle strength, power, mass, and density (i.e. quality) differ between children living with HIV (CWH) and those uninfected, and whether antiretroviral therapy (ART) regime is associated with muscle quality.Design: A cross-sectional study in Harare, Zimbabwe.Methods: The study recruited CWH aged 8–16years, taking ART for ≥2years, from HIV clinics, and HIV-uninfected children from local schools. Muscle outcomes comprised grip strength measured by hand-held Jamar dynamometer, lower-limb power measured by standing long-jump distance, lean mass measured by dual-energy X-ray absorptiometry, and muscle density (reflecting intramuscular fat) by peripheral quantitative computed tomography. Linear regression calculated adjusted mean differences (aMD) by HIV status.Results: Overall, 303 CWH and 306 without HIV, had mean(SD) age 12.5(2.5) years, BMI 17.5(2.8), with 50% female. Height and fat mass were lower in CWH, mean differences(SE) 7.4(1.1)cm and 2.7(0.4)kgs, respectively. Male CWH had lower grip strength (aMD 2.5[1.1,3.9]kg, P &lt; 0.001), long-jump distance (7.1[1.8,12.5]cm, P = 0.006), muscle density (0.58[0.12,1.05]mg/cm3, P = 0.018, but not lean mass 0.06[-1.08,1.21]kg, P = 0.891) versus boys without HIV; differences were consistent but smaller in females. Mediation analysis suggested the negative effect of HIV on jumping power in males was partially mediated by muscle density (P = 0.032). CWH taking tenofovir disoproxil fumarate (TDF) had lower muscle density (0.56[0.00,1.13]mg/cm3, P = 0.049) independent of fat mass, than CWH on other ART.Conclusions: Perinatally-acquired HIV is associated, particularly in males, with reduced upper and lower-limb muscle function, not mass. Intra-muscular fat (poorer muscle quality) partially explained reductions in lower-limb function. TDF is a novel risk factor for impaired muscle quality.</div

    Asylum-seekers and refugees: A structuration theory analysis of their experiences in the UK

    Get PDF
    This is the peer reviewed version of the following article: Healey, R. L. (2006). Asylum-seekers and refugees: A structuration theory analysis of their experiences in the UK 2006. Population, Space and Place, 12(4), pp. 257-271, which has been published in final form at http://dx.doi.org/10.1002/psp.412 . This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.Much of the literature on asylum seekers and refugees tends to be atheoretical. This article uses ideas from Giddens’ structuration theory as a conceptual framework to analyse the voices of a group of asylum seekers and refugees. The empirical database consists of semi-structured interviews with 18 asylum seekers and refugees living in the UK from a wide range of countries, including Ethiopia, Kenya, Poland, Somalia, and the Yemen. The study shows that the experiences of asylum seekers and refugees are impacted by both structural and individual agency factors. The former, it is argued, consist of public and political reaction towards the increase in the number of asylum applications, while the latter include asylum seeker and refugee experiences of specific places and people which can create social networks. Structural factors had the greatest impact upon the integration of the participants into the host society. The nature of the experiences of asylum seekers and refugees can influence the way they feel about their position in the host society. For example, negative experiences of the UK can reduce their sense of security in the society whereas positive experiences can increase their feelings of comfort. Structuration theory conceptualises how asylum seekers and refugees utilise coping strategies to raise their comfort level in the host country

    Acute intracerebral haemorrhage: diagnosis and management

    Get PDF
    Intracerebral haemorrhage (ICH) accounts for half of the disability-adjusted life years lost due to stroke worldwide. Care pathways for acute stroke result in the rapid identification of ICH, but its acute management can prove challenging because no individual treatment has been shown definitively to improve its outcome. Nonetheless, acute stroke unit care improves outcome after ICH, patients benefit from interventions to prevent complications, acute blood pressure lowering appears safe and might have a modest benefit, and implementing a bundle of high-quality acute care is associated with a greater chance of survival. In this article, we address the important questions that neurologists face in the diagnosis and acute management of ICH, and focus on the supporting evidence and practical delivery for the main acute interventions

    The association between retinal vascular geometry changes and diabetic retinopathy and their role in prediction of progression: an exploratory study

    Get PDF
    Background: The study describes the relationship of retinal vascular geometry (RVG) to severity of diabetic retinopathy (DR), and its predictive role for subsequent development of proliferative diabetic retinopathy (PDR). Methods. The research project comprises of two stages. Firstly, a comparative study of diabetic patients with different grades of DR. (No DR: Minimal non-proliferative DR: Severe non-proliferative DR: PDR) (10:10: 12: 19). Analysed RVG features including vascular widths and branching angles were compared between patient cohorts. A preliminary statistical model for determination of the retinopathy grade of patients, using these features, is presented. Secondly, in a longitudinal predictive study, RVG features were analysed for diabetic patients with progressive DR over 7 years. RVG at baseline was examined to determine risk for subsequent PDR development. Results: In the comparative study, increased DR severity was associated with gradual vascular dilatation (p = 0.000), and widening of the bifurcating angle (p = 0.000) with increase in smaller-child-vessel branching angle (p = 0.027). Type 2 diabetes and increased diabetes duration were associated with increased vascular width (p = <0.05 In the predictive study, at baseline, reduced small-child vascular width (OR = 0.73 (95 CI 0.58-0.92)), was predictive of future progression to PDR. Conclusions: The study findings suggest that RVG alterations can act as novel markers indicative of progression of DR severity and establishment of PDR. RVG may also have a potential predictive role in determining the risk of future retinopathy progression. © 2014 Habib et al.; licensee BioMed Central Ltd

    Clades of huge phages from across Earth's ecosystems

    Get PDF
    Bacteriophages typically have small genomes and depend on their bacterial hosts for replication. Here we sequenced DNA from diverse ecosystems and found hundreds of phage genomes with lengths of more than 200 kilobases (kb), including a genome of 735 kb, which is-to our knowledge-the largest phage genome to be described to date. Thirty-five genomes were manually curated to completion (circular and no gaps). Expanded genetic repertoires include diverse and previously undescribed CRISPR-Cas systems, transfer RNAs (tRNAs), tRNA synthetases, tRNA-modification enzymes, translation-initiation and elongation factors, and ribosomal proteins. The CRISPR-Cas systems of phages have the capacity to silence host transcription factors and translational genes, potentially as part of a larger interaction network that intercepts translation to redirect biosynthesis to phage-encoded functions. In addition, some phages may repurpose bacterial CRISPR-Cas systems to eliminate competing phages. We phylogenetically define the major clades of huge phages from human and other animal microbiomes, as well as from oceans, lakes, sediments, soils and the built environment. We conclude that the large gene inventories of huge phages reflect a conserved biological strategy, and that the phages are distributed across a broad bacterial host range and across Earth's ecosystems

    Non-variant specific antibody responses to the C-terminal region of merozoite surface protein-1 of Plasmodium falciparum (PfMSP-119) in Iranians exposed to unstable malaria transmission

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The C-terminal region of <it>Plasmodium falciparum </it>merozoite surface protein-1 (PfMSP-1<sub>19</sub>) is a leading malaria vaccine candidate antigen. However, the existence of different variants of this antigen can limit efficacy of the vaccine development based on this protein. Therefore, in this study, the main objective was to define the frequency of PfMSP-1<sub>19 </sub>haplotypes in malaria hypoendemic region of Iran and also to analyse cross-reactive and/or variant-specific antibody responses to four PfMSP-1<sub>19 </sub>variant forms.</p> <p>Methods</p> <p>The PfMSP-1<sub>19 </sub>was genotyped in 50 infected subjects with <it>P. falciparum </it>collected during 2006-2008. Four GST-PfMSP-1<sub>19 </sub>variants (E/TSR/L, E/TSG/L, E/KNG/F and Q/KNG/L) were produced in <it>Escherichia coli </it>and naturally occurring IgG antibody to these proteins was evaluated in malaria patients' sera (n = 50) using ELISA. To determine the cross-reactivity of antibodies against each PfMSP-1<sub>19 </sub>variant in <it>P. falciparum-</it>infected human sera, an antibody depletion assay was performed in eleven corresponding patients' sera.</p> <p>Results</p> <p>Sequence data of the PfMSP-1<sub>19 </sub>revealed five variant forms in which the haplotypes Q/KNG/L and Q/KNG/F were predominant types and the second most frequent haplotype was E/KNG/F. In addition, the prevalence of IgG antibodies to all four PfMSP-1<sub>19 </sub>variant forms was equal and high (84%) among the studied patients' sera. Immunodepletion results showed that in Iranian malaria patients, Q/KNG/L variant could induce not only cross-reactive antibody responses to other PfMSP-1<sub>19 </sub>variants, but also could induce some specific antibodies that are not able to recognize the E/TSG/L or E/TSR/L variant forms.</p> <p>Conclusion</p> <p>The present findings demonstrated the presence of non-variant specific antibodies to PfMSP-1<sub>19 </sub>in Iranian falciparum malaria patients. This data suggests that polymorphism in PfMSP-1<sub>19 </sub>is less important and one variant of this antigen, particularly Q/KNG/L, may be sufficient to be included in PfMSP-1<sub>19</sub>-based vaccine.</p

    Impact of five years of peer-mediated interventions on sexual behavior and sexually transmitted infections among female sex workers in Mombasa, Kenya

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Since 2000, peer-mediated interventions among female sex workers (FSW) in Mombasa Kenya have promoted behavioural change through improving knowledge, attitudes and awareness of HIV serostatus, and aimed to prevent HIV and other sexually transmitted infection (STI) by facilitating early STI treatment. Impact of these interventions was evaluated among those who attended peer education and at the FSW population level.</p> <p>Methods</p> <p>A pre-intervention survey in 2000, recruited 503 FSW using snowball sampling. Thereafter, peer educators provided STI/HIV education, condoms, and facilitated HIV testing, treatment and care services. In 2005, data were collected using identical survey methods, allowing comparison with historical controls, and between FSW who had or had not received peer interventions.</p> <p>Results</p> <p>Over five years, sex work became predominately a full-time activity, with increased mean sexual partners (2.8 versus 4.9/week; <it>P </it>< 0.001). Consistent condom use with clients increased from 28.8% (145/503) to 70.4% (356/506; <it>P </it>< 0.001) as well as the likelihood of refusing clients who were unwilling to use condoms (OR = 4.9, 95%CI = 3.7–6.6). In 2005, FSW who received peer interventions (28.7%, 145/506), had more consistent condom use with clients compared with unexposed FSW (86.2% versus 64.0%; AOR = 3.6, 95%CI = 2.1–6.1). These differences were larger among FSW with greater peer-intervention exposure. HIV prevalence was 25% (17/69) in FSW attending ≥ 4 peer-education sessions, compared with 34% (25/73) in those attending 1–3 sessions (P = 0.21). Overall HIV prevalence was 30.6 (151/493) in 2000 and 33.3% (166/498) in 2005 (<it>P </it>= 0.36).</p> <p>Conclusion</p> <p>Peer-mediated interventions were associated with an increase in protected sex. Though peer-mediated interventions remain important, higher coverage is needed and more efficacious interventions to reduce overall vulnerability and risk.</p
    corecore