43 research outputs found

    BioTile, A Perl based tool for the identification of differentially enriched regions in tiling microarray data

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    BACKGROUND: Genome-wide tiling array experiments are increasingly used for the analysis of DNA methylation. Because DNA methylation patterns are tissue and cell type specific, the detection of differentially methylated regions (DMRs) with small effect size is a necessary feature of tiling microarray ‘peak’ finding algorithms, as cellular heterogeneity within a studied tissue may lead to a dilution of the phenotypically relevant effects. Additionally, the ability to detect short length DMRs is necessary as biologically relevant signal may occur in focused regions throughout the genome. RESULTS: We present a free open-source Perl application, Binding Intensity Only Tile array analysis or “BioTile”, for the identification of differentially enriched regions (DERs) in tiling array data. The application of BioTile to non-smoothed data allows for the identification of shorter length and smaller effect-size DERs, while correcting for probe specific variation by inversely weighting on probe variance through a permutation corrected meta-analysis procedure employed at identified regions. BioTile exhibits higher power to identify significant DERs of low effect size and across shorter genomic stretches as compared to other peak finding algorithms, while not sacrificing power to detect longer DERs. CONCLUSION: BioTile represents an easy to use analysis option applicable to multiple microarray platforms, allowing for its integration into the analysis workflow of array data analysis

    Capacity for absorption of water-soluble secondary metabolites greater in birds than in rodents

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    Plant secondary metabolites (SMs) are pervasive in animal foods and potentially influence feeding behavior, interspecies interactions, and the distribution and abundance of animals. Some of the major classes of naturally occurring SMs in plants include many water-soluble compounds in the molecular size range that could cross the intestinal epithelium via the paracellular space by diffusion or solvent drag. There are differences among species in paracellular permeability. Using Middle Eastern rodent and avian consumers of fruits containing SMs, we tested the hypothesis that avian species would have significantly higher paracellular permeability than rodent species. Permeability in intact animals was assessed using standard pharmacological methodology to measure absorption of two radiolabeled, inert, neutral water-soluble probes that do not interact with intestinal nutrient transporters, L-arabinose (M r = 150.1 Da) and lactulose (M r = 342.3 Da). We also measured absorption of labeled 3-O-methyl-D-glucose (3OMD-glucose; M r = 194.2 Da), which is a nonmetabolized analogue of D-glucose that is passively absorbed through the paracellular space but also transported across the enterocyte membranes. Most glucose was absorbed by all species, but arabinose fractional absorption (f) was nearly three times higher in birds (1.03±0.17, n = 15 in two species) compared to rodents (0.37±0.06, n = 10 in two species) (P<0.001). Surprisingly, the apparent rates of absorption in birds of arabinose exceeded those of 3OMD-glucose. Our findings are in agreement with previous work showing that the paracellular pathway is more prominent in birds relative to nonflying mammals, and suggests that birds may be challenged by greater absorption of water-soluble, dietary SMs. The increased expression of the paracellular pathway in birds hints at a tradeoff: the free energy birds gain by absorbing water-soluble nutrients passively may be offset by the metabolic demands placed on them to eliminate concomitantly absorbed SMs.Fil: Karasov, William. University of Wisconsin; Estados UnidosFil: Caviedes Vidal, Enrique Juan Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; ArgentinaFil: Bakken, Bradley Hartman. University of Wisconsin; Estados UnidosFil: Izhaki, Ido. University Of Haifa; IsraelFil: Samuni Blank, Michal. University Of Haifa; IsraelFil: Arad, Zeev. University Of Haifa; Israe

    Mapping Awareness-Raising and Capacity-Building Materials on Developmental Disabilities for Non-Specialists: a Review of the Academic and Grey Literature

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    Most children with developmental disabilities (DD), such as intellectual disabilities and autism, live in low- and middle-income countries (LMICs), where services are usually limited. Various governmental, non-governmental and research organisations in LMICs have developed awareness-raising campaigns and training and education resources on DD in childhood relevant to LMICs. This study aimed to comprehensively search and review freely available materials in the academic and grey literature, aimed at awareness raising, training and education on DD among non-specialist professionals and community members in LMICs. We consulted 183 experts, conducted key-word searches in five academic databases, four grey-literature databases and seventeen customised Google search engines. Following initial screening, we manually searched relevant systematic reviews and lists of resources and conducted forwards and backwards citation checks of included articles. We identified 7327 articles and resources after deduplication. We then used a rigorous multi-step screening process to select 78 training resources on DD relevant to LMICs, of which 43 aimed at informing and/or raising awareness DD, 16 highlighted specific strategies for staff in health settings and 19 in education settings. Our mapping analysis revealed that a wealth of materials is available for both global and local use, including comics, children’s books, flyers, posters, fact sheets, blogs, videos, websites pages, social media channels, handbooks and self-education guides, and training programmes or sessions. Twelve resources were developed for cross-continental or global use in LMICs, 19 were developed for and/or used in Africa, 23 in Asia, 24 in Latin America. Most resources were developed within the context where they were intended to be used. Identified gaps included a limited range of resources on intellectual disabilities, manuals for actively delivering training to staff in education settings and resources targeted at eastern European LMICs: future intervention development and adaptation efforts should address such gaps, to ensure capacity building materials exist for a sufficient variety of DD, settings and geographical areas. Beyond identifying these gaps, the value of the review lies in the compilation of summary tables of information on all freely available resources found, to support their selection and use in wider contexts. Information on the resource content, country of original development and copyright is provided to facilitate resource sharing and uptake

    Mapping Awareness-Raising and Capacity-Building Materials on Developmental Disabilities for Non-Specialists: a Review of the Academic and Grey Literature

    Get PDF
    Most children with developmental disabilities (DD), such as intellectual disabilities and autism, live in low- and middle-income countries (LMICs), where services are usually limited. Various governmental, non-governmental and research organisations in LMICs have developed awareness-raising campaigns and training and education resources on DD in childhood relevant to LMICs. This study aimed to comprehensively search and review freely available materials in the academic and grey literature, aimed at awareness raising, training and education on DD among non-specialist professionals and community members in LMICs. We consulted 183 experts, conducted key-word searches in five academic databases, four grey-literature databases and seventeen customised Google search engines. Following initial screening, we manually searched relevant systematic reviews and lists of resources and conducted forwards and backwards citation checks of included articles. We identified 7327 articles and resources after deduplication. We then used a rigorous multi-step screening process to select 78 training resources on DD relevant to LMICs, of which 43 aimed at informing and/or raising awareness DD, 16 highlighted specific strategies for staff in health settings and 19 in education settings. Our mapping analysis revealed that a wealth of materials is available for both global and local use, including comics, children’s books, flyers, posters, fact sheets, blogs, videos, websites pages, social media channels, handbooks and self-education guides, and training programmes or sessions. Twelve resources were developed for cross-continental or global use in LMICs, 19 were developed for and/or used in Africa, 23 in Asia, 24 in Latin America. Most resources were developed within the context where they were intended to be used. Identified gaps included a limited range of resources on intellectual disabilities, manuals for actively delivering training to staff in education settings and resources targeted at eastern European LMICs: future intervention development and adaptation efforts should address such gaps, to ensure capacity building materials exist for a sufficient variety of DD, settings and geographical areas. Beyond identifying these gaps, the value of the review lies in the compilation of summary tables of information on all freely available resources found, to support their selection and use in wider contexts. Information on the resource content, country of original development and copyright is provided to facilitate resource sharing and uptake.</p

    C-reactive protein serum levels as an early predictor of outcome in patients with pandemic H1N1 influenza A virus infection

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    <p>Abstract</p> <p>Background</p> <p>Data for predicting which patients with pandemic influenza A (H1N1) infection are likely to run a complicated course are sparse. We retrospectively studied whether the admission serum C-reactive protein (CRP) levels can serve as a predictor of illness severity.</p> <p>Methods</p> <p>Included were all consecutive adult patients who presented to the emergency department (ED) between May-December, 2009 with a flu-like illness, a confirmed diagnosis of pandemic influenza A (H1N1) infection and a serum CRP level measured within 24 hours of presentation. Patients with a proven additional concurrent acute illness (e.g., bacteremia) were excluded. We used the ROC curve analysis, Kaplan-Meier curves and the Cox proportional hazard model to evaluate the predictive ability of CRP as a prognostic factor.</p> <p>Results</p> <p>Seventeen (9%) of the 191 enrolled patients were admitted to the intensive care unit (ICU), of whom eight (4%) required mechanical ventilation and three (2%) died. The median admission serum CRP levels were significantly higher among patients who required subsequent ICU care and mechanical ventilation than among patients who did not (123 mg/L and 112 mg/L vs. 40 mg/L, <it>p </it>< .001 and 43 mg/L, <it>p </it>= .017, respectively). A Cox proportional hazard model identified admission serum CRP levels and auscultatory findings over the lungs as independent prognostic factors for ICU admission. Admission serum CRP levels were the only independent prognostic factor for mechanical ventilation. Thirty days after presenting to the ED, none of the patients with admission serum CRP level <28 mg/L (lower tertile) required either ICU admission or mechanical ventilation. At the same time point, 19% of the patients with admission serum CRP level ≥70 mg/L (upper tertile) needed to be admitted to the ICU and 8% of the same upper tertile group required mechanical ventilation. The differences in the rates between the lower vs. upper tertile groups were significant (Log-Rank <it>p </it>< .001 for ICU and <it>p </it>< .024 for mechanical ventilation).</p> <p>Conclusions</p> <p>In our study group, serum CRP levels obtained in the early ED admission stage from patients presenting with pandemic H1N1 influenza A infection were found to serve as a useful gauge for predicting disease course and assisting in patient management.</p

    Chimeric DNA methyltransferases target DNA methylation to specific DNA sequences and repress expression of target genes

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    Gene silencing by targeted DNA methylation has potential applications in basic research and therapy. To establish targeted methylation in human cell lines, the catalytic domains (CDs) of mouse Dnmt3a and Dnmt3b DNA methyltransferases (MTases) were fused to different DNA binding domains (DBD) of GAL4 and an engineered Cys2His2 zinc finger domain. We demonstrated that (i) Dense DNA methylation can be targeted to specific regions in gene promoters using chimeric DNA MTases. (ii) Site-specific methylation leads to repression of genes controlled by various cellular or viral promoters. (iii) Mutations affecting any of the DBD, MTase or target DNA sequences reduce targeted methylation and gene silencing. (iv) Targeted DNA methylation is effective in repressing Herpes Simplex Virus type 1 (HSV-1) infection in cell culture with the viral titer reduced by at least 18-fold in the presence of an MTase fused to an engineered zinc finger DBD, which binds a single site in the promoter of HSV-1 gene IE175k. In short, we show here that it is possible to direct DNA MTase activity to predetermined sites in DNA, achieve targeted gene silencing in mammalian cell lines and interfere with HSV-1 propagation

    High Cooperativity of the SV40 Major Capsid Protein VP1 in Virus Assembly

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    SV40 is a small, non enveloped DNA virus with an icosahedral capsid of 45 nm. The outer shell is composed of pentamers of the major capsid protein, VP1, linked via their flexible carboxy-terminal arms. Its morphogenesis occurs by assembly of capsomers around the viral minichromosome. However the steps leading to the formation of mature virus are poorly understood. Intermediates of the assembly reaction could not be isolated from cells infected with wt SV40. Here we have used recombinant VP1 produced in insect cells for in vitro assembly studies around supercoiled heterologous plasmid DNA carrying a reporter gene. This strategy yields infective nanoparticles, affording a simple quantitative transduction assay. We show that VP1 assembles under physiological conditions into uniform nanoparticles of the same shape, size and CsCl density as the wild type virus. The stoichiometry is one DNA molecule per capsid. VP1 deleted in the C-arm, which is unable to assemble but can bind DNA, was inactive indicating genuine assembly rather than non-specific DNA-binding. The reaction requires host enzymatic activities, consistent with the participation of chaperones, as recently shown. Our results demonstrate dramatic cooperativity of VP1, with a Hill coefficient of ∼6. These findings suggest that assembly may be a concerted reaction. We propose that concerted assembly is facilitated by simultaneous binding of multiple capsomers to a single DNA molecule, as we have recently reported, thus increasing their local concentration. Emerging principles of SV40 assembly may help understanding assembly of other complex systems. In addition, the SV40-based nanoparticles described here are potential gene therapy vectors that combine efficient gene delivery with safety and flexibility

    Caloric Restriction Ameliorates Cardiomyopathy in Animal Model of Diabetes

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    BACKGROUND: The db/db mouse is an animal model of diabetes in which leptin receptor activity is deficient resulting accelerated cardiomyopathy when exposed to angiotensin (AT). Toll-like receptors 4 and 2 (TLR4, TLR2) are pattern recognition receptors, that recognize pathogen-associated molecular patterns and exacerbate and release inflammatory cytokines. Fetuin A (Fet A) is a fatty acid carrier which affects inflammation and insulin resistance in obese humans and animals through TLRs. The aim of this study was to investigate the effect of caloric restriction (CR) on free fatty acids (FFA) level and the inflammatory response in diabetic cardiomyopathy. METHODS AND RESULTS: Left ventricular hypertrophy, increased fibrosis and leukocytes infiltration were observed in db/db AT treated hearts. Serum glucose, FFA, and cholesterol levels were elevated in db/db AT treated mice. Cardiac expression of PPARalpha increased while AKT phosphorylation was decreased. CONCLUSIONS: Cumulatively, CR elevated cardiac PPARalpha improved the utilization of fatty acids, and reduced myocardial inflammation as seen by reduced levels of Fet A. Thus CR negated cardiomyopathy associated with AT in an animal model of diabetes suggesting that CR is an effective therapeutic approach in the treatment of diabetes and associated cardiomyopathy
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