377 research outputs found

    Amplifying control RNA for RT-PCR applications by nucleic acid sequence based amplification (NASBA)

    Get PDF
    Control RNA for RT-PCR applications was amplified by nucleic acid sequence based amplification (NASBA) using the NucliSens (R) Basic Kit. This method was used to construct positive control RNA for enterovirus, insulin, and G-protein RT-PCR, and for interferon-alpha real-time RT-PCR. The primers were designed to amplify identical RNA from RNA templates, which differs from the usual NASBA procedure, where opposite strand RNA is amplified from the target. This "inverse NASBA" method is easy to use and it does not require any expensive special equipment. The amplification reaction is done using a water bath and detection of amplified product by agarose gel electrophoresis. Generated RNA fragments were 195-714 bases long, of positive polarity and the amount of RNA was sufficient for thousands of RT-PCR reactions depending on the sensitivity of the RT-PCR. (c) 2005 Elsevier B.V. All rights reserved

    PCR inhibition in stool samples in relation to age of infants

    Get PDF
    Background: PCR is rapidly replacing traditional methods in diagnostic virus laboratories. PCR inhibitors,which are often present in clinical samples, may lead to false negative test results.Objectives: The aim was to study the presence of PCR inhibitors in stool samples collected from 3- to24-month old children.Study design: Total RNA fraction extracted from stool samples was spiked with a standardized amount ofSemliki Forest Virus RNA and amplified using specific PCR primers. The presence of PCR inhibitors wasdetected by a decrease in amplification rate compared to spiked water samples. Inhibition in differentage groups and dietary origin of PCR inhibitors were analyzed by comparing the samples taken duringexclusive and non-exclusive breastfeeding periods. The inactivation of PCR inhibitors was also assessed.Results: Complete inhibition was seen in 12% (13/108) and partial inhibition in 19% (21/108) of the samples.Inhibition was seen in none of the stool samples (0/31) taken from infants younger than 6 monthscompared to 17% of samples (13/77) taken from6 to 24 months old infants (p more common in younger age group. Addition of bovine serum albumin (BSA) into the reaction mixtureseliminated the effect of inhibitors leading to all samples being positive.Conclusions: PCR inhibitors are frequent in stool samples. They may originate from dietary componentsand can lead to false negative PCR results. The addition of BSA to the cDNA and PCR reactions proved tobe an easy and effective method for eliminating the inhibitory effect of these compounds

    Simulation and data processing of GOMOS measurements

    Get PDF
    In this paper the data simulation and data inversion studies for stellar occultation measurements are discussed. The specific application is the Global Ozone Monitoring by Occultation of Stars (GOMOS) instrument which has been proposed for the first European Platform, Polar Orbiting Earth Mission (POEM-1)

    Molecular analysis of an echovirus 3 strain isolated from an individual concurrently with appearance of islet cell and IA-2 autoantibodies

    Get PDF
    Growing evidence has implicated members of the genus Enterovirus of the family Picornaviridae in the etiology of some cases of type I diabetes (T1D). To contribute to an understanding of the molecular determinants underlying this association, we determined the complete nucleotide sequence of a strain of echovirus 3 (E3), Human enterovirus B (HEV-B) species, isolated from an individual who soon after virus isolation developed autoantibodies characteristic of T1D. The individual has remained positive for over 6 years for tyrosine phosphatase-related IA-2 protein autoantibodies and islet cell autoantibodies, indicating an ongoing autoimmune process, although he has not yet developed clinical T1D. The sequence obtained adds weight to the observation that recent enterovirus isolates differ significantly from prototype strains and provides further evidence of a role for recombination in enterovirus evolution. In common with most HEV-B species members, the isolate exhibits 2C and VP1 sequences suggested as triggers of autoimmunity through molecular mimicry. However, comparisons with the E3 prototype strain and previously reported diabetogenic and nondiabetogenic HEV-B strains do not reveal clear candidates for sequence features of PicoBank/DM1/E3 that could be associated with autoantibody appearance. This is the first time a virus strain isolated at the time of commencement of beta-cell damage has been analyzed and is an invaluable addition to enterovirus strains isolated previously at the onset of T1D in the search for specific molecular features which could be associated with diabetes induction

    Analysis of pancreas tissue in a child positive for islet cell antibodies

    Get PDF
    Conclusions/interpretation These observations suggest that positivity for ICA alone, even when lasting for more than 1 year, is not associated with inflammatory changes in the islets. However, it is most likely that the pancreatic islets were infected by an enterovirus in this child

    Detection of a low-grade enteroviral infection in the islets of Langerhans of living patients newly diagnosed with type 1 diabetes

    Get PDF
    Journal ArticleThis is an author-created, uncopyedited electronic version of an article accepted for publication in Diabetes. The American Diabetes Association (ADA), publisher of Diabetes, is not responsible for any errors or omissions in this version of the manuscript or any version derived from it by third parties. The definitive publisher-authenticated version is available in Diabetes, May 2015, vol. 64, no. 5 pp. 1682-1687 in print and online at http://diabetes.diabetesjournals.org/content/64/5/1682.abstractThe Diabetes Virus Detection study (DiViD) is the first to examine fresh pancreatic tissue at the diagnosis of type 1 diabetes for the presence of viruses. Minimal pancreatic tail resection was performed 3-9 weeks after onset of type 1 diabetes in six adult patients (age 24-35 years). The presence of enteroviral capsid protein 1 (VP1) and the expression of class I HLA were investigated by immunohistochemistry. Enterovirus RNA was analyzed from isolated pancreatic islets and from fresh-frozen whole pancreatic tissue using PCR and sequencing. Nondiabetic organ donors served as controls. VP1 was detected in the islets of all type 1 diabetic patients (two of nine controls). Hyperexpression of class I HLA molecules was found in the islets of all patients (one of nine controls). Enterovirus-specific RNA sequences were detected in four of six patients (zero of six controls). The results were confirmed in various laboratories. Only 1.7% of the islets contained VP1(+) cells, and the amount of enterovirus RNA was low. The results provide evidence for the presence of enterovirus in pancreatic islets of type 1 diabetic patients, which is consistent with the possibility that a low-grade enteroviral infection in the pancreatic islets contributes to disease progression in humans.Academy of FinlandSouth-Eastern Norway Regional HealthAuthorityNovo Nordisk FoundationPEVNET (Persistent Virus Infection in Diabetes Network) Study GroupEuropean Union’s Seventh Framework ProgrammeSwedish Medical Research CouncilDiabetes Wellness FoundationJDR

    Genome-wide association study of nocturnal blood pressure dipping in hypertensive patients

    Get PDF
    Abstract Background Reduced nocturnal fall (non-dipping) of blood pressure (BP) is a predictor of cardiovascular target organ damage. No genome-wide association studies (GWAS) on BP dipping have been previously reported. Methods To study genetic variation affecting BP dipping, we conducted a GWAS in Genetics of Drug Responsiveness in Essential Hypertension (GENRES) cohort (n = 204) using the mean night-to-day BP ratio from up to four ambulatory BP recordings conducted on placebo. Associations with P < 1 × 10− 5 were further tested in two independent cohorts: Haemodynamics in Primary and Secondary Hypertension (DYNAMIC) (n = 183) and Dietary, Lifestyle and Genetic determinants of Obesity and Metabolic Syndrome (DILGOM) (n = 180). We also tested the genome-wide significant single nucleotide polymorphism (SNP) for association with left ventricular hypertrophy in GENRES. Results In GENRES GWAS, rs4905794 near BCL11B achieved genome-wide significance (β = − 4.8%, P = 9.6 × 10− 9 for systolic and β = − 4.3%, P = 2.2 × 10− 6 for diastolic night-to-day BP ratio). Seven additional SNPs in five loci had P values < 1 × 10− 5. The association of rs4905794 did not significantly replicate, even though in DYNAMIC the effect was in the same direction (β = − 0.8%, P = 0.4 for systolic and β = − 1.6%, P = 0.13 for diastolic night-to-day BP ratio). In GENRES, the associations remained significant even during administration of four different antihypertensive drugs. In separate analysis in GENRES, rs4905794 was associated with echocardiographic left ventricular mass (β = − 7.6 g/m2, P = 0.02). Conclusions rs4905794 near BCL11B showed evidence for association with nocturnal BP dipping. It also associated with left ventricular mass in GENRES. Combined with earlier data, our results provide support to the idea that BCL11B could play a role in cardiovascular pathophysiology

    Effect of inactivated nature-derived microbial composition on mouse immune system

    Get PDF
    Introduction: The hygiene hypothesis suggests that decrease in early life infections due to increased societal-level hygiene standards subjects one to allergic and autoimmune diseases. In this report, we have studied the effect of sterilized forest soil and plant-based material on mouse immune system and gut microbiome. Methods: Inbred C57Bl/6 mice maintained in normal sterile environment were subjected to autoclaved forest soil-derived powder in their bedding for 1 h a day for 3 weeks. Immune response was measured by immune cell flow cytometry, serum cytokine enzyme-linked immunoassay (ELISA) and quantitative polymerase chain reaction (qPCR) analysis. Furthermore, the mouse gut microbiome was analyzed by sequencing. Results: When compared to control mice, mice treated with soil-derived powder had decreased level of pro-inflammatory cytokines namely interleukin (IL)-17F and IL-21 in the serum. Furthermore, splenocytes from mice treated with soil-derived powder expressed less IL-1b, IL-5, IL-6, IL-13, and tumor necrosis factor (TNF) upon cell activation. Gut microbiome appeared to be stabilized by the treatment. Conclusions: These results provide insights on the effect of biodiversity on murine immune system in sterile environment. Subjecting mice to soil-based plant and microbe structures appears to elicit immune response that could be beneficial, for example, in type 2 inflammation-related diseases, that is, allergic diseases.Peer reviewe

    Skin, gut, and sand metagenomic data on placebo-controlled sandbox biodiversity intervention study

    Get PDF
    The metagenomic data presented in this article are related to the published research of "A Placebo-controlled doubleblinded test of the biodiversity hypothesis of immunemediated diseases: Environmental microbial diversity elicits changes in cytokines and increase in T regulatory cells in young children"This database contains 16S ribosomal RNA (rRNA) metagenomics of sandbox sand and skin and gut microbiota of children in the intervention and placebo daycares. In inter-vention daycares, children aged 3-5 years were exposed to playground sand enriched with microbially diverse soil. In placebo daycares, children were exposed to visually similar as in intervention daycares, but microbially poor sand col-ored with peat. Sand, skin and gut metagenomics were an-alyzed at baseline and after 14 and 28 days of interven-tion by high throughput sequencing of bacterial 16S rRNA gene on the Illumina MiSeq platform. This dataset shows how skin bacterial community composition, including classes Gammaproteobacteria and Bacilli, changed, and how the rel-ative abundance of over 30 bacterial genera shifted on the skin of children in the intervention treatment, while no shifts occurred in the placebo group.(c) 2023 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)Peer reviewe
    corecore