67 research outputs found

    Persistent prion infection disturbs the function of Oct-1, resulting in the down-regulation of murine interferon regulatory factor-3

    Get PDF
    As a prompt response against invasion of various viruses, interferon regulatory factor-3 (IRF-3) is initially phosphorylated to become activated and upregulates mainly Type I Interferons (IFN-I) in most cell types. We previously reported that IRF-3-dependent host innate immune responses partially interfere in infection of prions. Here, we found that stable infection of prion suppressed IRF-3 gene-expression. The decreased promoter activity of IRF-3 was significantly restored along with treatment of anti-prion drugs in the prion-infected cells, suggesting that infection of prion directly influence the regulation of IRF-3 transcription. We further investigated promoter activity of 5\u27- flanking region of murine IRF-3 using a luciferase reporter system and found that the nucleotides -119 to -1 were indispensable for the promoter activity. Within this region, mutations in the Oct-1 binding site significantly reduced the promoter activity and chromatin immunoprecipitation (ChIP) assay revealed that Oct-1 indeed binds to the region. In addition, overexpression of Oct-1 increased the promoter activity of IRF-3. Intriguingly, Oct-1 protein was significantly reduced in prion-infected cells and mice brains compared with uninfected groups. Taken together, we concluded that prion infection could interfere in the function of Oct-1, resulting in the down-regulation of IRF-3

    Reduced Risk of Malaria Parasitemia Following Household Screening and Treatment: A Cross-Sectional and Longitudinal Cohort Study

    Get PDF
    BACKGROUND: In regions of declining malaria transmission, new strategies for control are needed to reduce transmission and achieve elimination. Artemisinin-combination therapy (ACT) is active against immature gametocytes and can reduce the risk of transmission. We sought to determine whether household screening and treatment of infected individuals provides protection against infection for household members. METHODOLOGY/PRINCIPAL FINDINGS: The study was conducted in two areas in Southern Province, Zambia in 2007 and 2008/2009. To determine the impact of proactive case detection, households were randomly selected either to join a longitudinal cohort, in which participants were repeatedly screened throughout the year and those infected treated with artemether-lumefantrine, or a cross-sectional survey, in which participants were visited only once. Cross-sectional surveys were conducted throughout the year. The prevalence of RDT positivity was compared between the longitudinal and cross-sectional households at baseline and during follow-up using multilevel logistic regression. In the 2007 study area, 174 and 156 participants enrolled in the cross-sectional and longitudinal groups, respectively. In the 2008/2009 study area, 917 and 234 participants enrolled in the cross-sectional and longitudinal groups, respectively. In both study areas, participants and households in the longitudinal and cross-sectional groups were similar on demographic characteristics and prevalence of RDT positivity at baseline (2007: OR = 0.97; 95% CI:0.46, 2.03 | 2008/2009: OR = 1.28; 95% CI:0.44, 3.79). After baseline, the prevalence of RDT positivity was significantly lower in longitudinal compared to cross-sectional households in both study areas (2007: OR = 0.44; 95% CI:0.20, 0.96 | 2008/2009: OR = 0.16; 95% CI:0.05, 0.55). CONCLUSIONS/SIGNIFICANCE: Proactive case detection, consisting of screening household members with an RDT and treating those positive with ACT, can reduce transmission and provide indirect protection to household members. A targeted test and treat strategy could contribute to the elimination of malaria in regions of low transmission

    Convergence of marine megafauna movement patterns in coastal and open oceans

    Get PDF
    The extent of increasing anthropogenic impacts on large marine vertebrates partly depends on the animals’ movement patterns. Effective conservation requires identification of the key drivers of movement including intrinsic properties and extrinsic constraints associated with the dynamic nature of the environments the animals inhabit. However, the relative importance of intrinsic versus extrinsic factors remains elusive. We analyze a global dataset of ∼2.8 million locations from >2,600 tracked individuals across 50 marine vertebrates evolutionarily separated by millions of years and using different locomotion modes (fly, swim, walk/paddle). Strikingly, movement patterns show a remarkable convergence, being strongly conserved across species and independent of body length and mass, despite these traits ranging over 10 orders of magnitude among the species studied. This represents a fundamental difference between marine and terrestrial vertebrates not previously identified, likely linked to the reduced costs of locomotion in water. Movement patterns were primarily explained by the interaction between species-specific traits and the habitat(s) they move through, resulting in complex movement patterns when moving close to coasts compared with more predictable patterns when moving in open oceans. This distinct difference may be associated with greater complexity within coastal microhabitats, highlighting a critical role of preferred habitat in shaping marine vertebrate global movements. Efforts to develop understanding of the characteristics of vertebrate movement should consider the habitat(s) through which they move to identify how movement patterns will alter with forecasted severe ocean changes, such as reduced Arctic sea ice cover, sea level rise, and declining oxygen content

    The potential impact of expanding target age groups for polio immunization campaigns

    Get PDF
    BACKGROUND: Global efforts to eradicate wild polioviruses (WPVs) continue to face challenges due to uninterrupted endemic WPV transmission in three countries and importation-related outbreaks into previously polio-free countries. We explore the potential role of including older children and adults in supplemental immunization activities (SIAs) to more rapidly increase population immunity and prevent or stop transmission. METHODS: We use a differential equation-based dynamic poliovirus transmission model to analyze the epidemiological impact and vaccine resource implications of expanding target age groups in SIAs. We explore the use of older age groups in SIAs for three situations: alternative responses to the 2010 outbreak in Tajikistan, retrospective examination of elimination in two high-risk states in northern India, and prospective and retrospective strategies to accelerate elimination in endemic northwestern Nigeria. Our model recognizes the ability of individuals with waned mucosal immunity (i.e., immunity from a historical live poliovirus infection) to become re-infected and contribute to transmission to a limited extent. RESULTS: SIAs involving expanded age groups reduce overall caseloads, decrease transmission, and generally lead to a small reduction in the time to achieve WPV elimination. Analysis of preventive expanded age group SIAs in Tajikistan or prior to type-specific surges in incidence in high-risk areas of India and Nigeria showed the greatest potential benefits of expanded age groups. Analysis of expanded age group SIAs in outbreak situations or to accelerate the interruption of endemic transmission showed relatively less benefit, largely due to the circulation of WPV reaching individuals sooner or more effectively than the SIAs. The India and Nigeria results depend strongly on how well SIAs involving expanded age groups reach relatively isolated subpopulations that sustain clusters of susceptible children, which we assume play a key role in persistent endemic WPV transmission in these areas. CONCLUSIONS: This study suggests the need to carefully consider the epidemiological situation in the context of decisions to use expanded age group SIAs. Subpopulations of susceptible individuals may independently sustain transmission, which will reduce the overall benefits associated with using expanded age group SIAs to increase population immunity to a sufficiently high level to stop transmission and reduce the incidence of paralytic cases

    Cloning of a gene (SR-A1), encoding for a new member of the human Ser/Arg-rich family of pre-mRNA splicing factors: overexpression in aggressive ovarian cancer

    Get PDF
    By using the positional cloning gene approach, we were able to identify a novel gene encoding for a serine/arginine-rich protein, which appears to be the human homologue of the rat A1 gene. We named this new gene SR-A1. Members of the SR family of proteins have been shown to interact with the C-terminal domain (CTD) of the large subunit of RNA polymerase II and participate in pre-mRNA splicing. We have localized the SR-A1 gene between the known genes IRF3 and RRAS on chromosome 19q13.3. The novel gene spans 16.7 kb of genomic sequence and it is formed of 11 exons and 10 intervening introns. The SR-A1 protein is composed of 1312 amino acids, with a molecular mass of 139.3 kDa and a theoretical isoelectric point of 9.31. The SR-A1 protein contains an SR-rich domain as well as a CTD-binding domain present only in a subset of SR-proteins. Through interactions with the pre-mRNA and the CTD domain of the Polymerase II, SR proteins have been shown to regulate alternative splicing. The SR-A1 gene is expressed in all tissues tested, with highest levels found in fetal brain and fetal liver. Our data suggest that this gene is overexpressed in a subset of ovarian cancers which are clinically more aggressive. Studies with the steroid hormone receptor-positive breast and prostate carcinoma cell lines ZR-75-1, BT-474 and LNCaP, respectively, suggest that SR-A1 is constitutively expressed. Furthermore, the mRNA of the SR-A1 gene in these cell lines appears to increase by estrogens, androgens and glucocorticoids, and to a lesser extend by progestins. © 2001 Cancer Research Campaign http://www.bjcancer.co

    Finding Diagnostically Useful Patterns in Quantitative Phenotypic Data.

    Get PDF
    Trio-based whole-exome sequence (WES) data have established confident genetic diagnoses in ∼40% of previously undiagnosed individuals recruited to the Deciphering Developmental Disorders (DDD) study. Here we aim to use the breadth of phenotypic information recorded in DDD to augment diagnosis and disease variant discovery in probands. Median Euclidean distances (mEuD) were employed as a simple measure of similarity of quantitative phenotypic data within sets of ≥10 individuals with plausibly causative de novo mutations (DNM) in 28 different developmental disorder genes. 13/28 (46.4%) showed significant similarity for growth or developmental milestone metrics, 10/28 (35.7%) showed similarity in HPO term usage, and 12/28 (43%) showed no phenotypic similarity. Pairwise comparisons of individuals with high-impact inherited variants to the 32 individuals with causative DNM in ANKRD11 using only growth z-scores highlighted 5 likely causative inherited variants and two unrecognized DNM resulting in an 18% diagnostic uplift for this gene. Using an independent approach, naive Bayes classification of growth and developmental data produced reasonably discriminative models for the 24 DNM genes with sufficiently complete data. An unsupervised naive Bayes classification of 6,993 probands with WES data and sufficient phenotypic information defined 23 in silico syndromes (ISSs) and was used to test a "phenotype first" approach to the discovery of causative genotypes using WES variants strictly filtered on allele frequency, mutation consequence, and evidence of constraint in humans. This highlighted heterozygous de novo nonsynonymous variants in SPTBN2 as causative in three DDD probands
    • …
    corecore