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《Clinical and diagnostic virology》1998,9(2-3):89-98
Background: Several lines of evidence suggest that enterovirus infections may be involved in the etiology of the insulin-dependent diabetes mellitus (IDDM). Often in the literature, a reference is given to specifically diabetogenic strains of enterovirus but there is no systematic assessment about the generation of such strains in the course of evolution or about their abundance among the 64 enterovirus serotypes pathogenic to man. If enteroviruses truly are involved in the etiology of IDDM, a possibility to prevent the disease with enterovirus vaccines might become feasible. In such a situation it would be important to know which serotypes and strains are the most important ones, and whether there would be differences between the strains as regards the pathogenetic mechanisms involved.Objective: To present a brief summary of the basic biology of enteroviruses, on existing data of genetic variation of enteroviruses, and on molecular epidemiology of human enteroviruses with special reference to the different epidemiological modes of their putative involvement in the pathogenesis of IDDM.Conclusions: Like RNA viruses in general, enteroviruses exist as a quasispecies, a mixture of genetic microvariants with a vast potential to adapt to new environments. This means that specifically beta cell-tropic and potentially diabetogenic variants could, in theory, emerge sporadically during systemic infection of any individual. The patterns of genetic diversification of enteroviruses, cocirculation of separate genetic lineages in the human populations, and the assumed geographical restrictions of endemic transmission of the lineages, allow one to hypothesize that populations with a high persisting IDDM incidence might be endemically infected by some specific strains of enteroviruses. However, so far, there is no systematically collected data supporting this hypothesis. 相似文献
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Aims: Classic virological tests are time consuming and labour‐intensive; real‐time RT‐PCR has proven to be a fast method to detect and quantify enterovirus genomes in clinical and environmental samples. This method is unable to discriminate between infective and noninfective enterovirus particles; few clinical studies have compared real‐time RT‐PCR and viral culture. We wondered if the enterovirus genome quantification could be correlated to the infectivity. Methods and Results: We used the statistical approach to verify our hypotheses to correlate data, obtained by the standard method (most probable number of cytopathic units—MPNCU) and molecular test (real‐time RT‐PCR), on wastewater treatment plant samples. Chi‐squared test was used, considering several cut‐off values (‘50’‐‘100’‐‘200’ genome copy numbers), to determine statistical significance in comparison of the two methods. Chi‐square value was not significant when cut‐off of 50 (P = 0·103) and 100 (P = 0·178) was assumed but was significant with cut‐off of 200 (P = 0·044). Conclusion: This limit, 200 genome copy, could be used as cut‐off value to indicate enterovirus survival in environmental monitoring. Significant and Impact of the Study: To introduce a fast procedure that is able to compensate for disadvantages of cell culture method for viral environmental analyses. 相似文献
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Quantification of enterovirus RNA in sludge samples using single tube real-time RT-PCR 总被引:2,自引:0,他引:2
Monpoeho S Dehée A Mignotte B Schwartzbrod L Marechal V Nicolas JC Billaudel S Férré V 《BioTechniques》2000,29(1):88-93
We have developed a quantitative RT-PCR method that can be used to determine the amount of enterovirus RNA in urban sludge samples. This method combines Taq-Man technology with the ABI Prism 7700 real-time sequence detection system. We optimized a one-step RT-PCR that uses a dual-labeled fluorogenic probe to quantify the 5' noncoding region of enteroviruses. For accurate quantification of the number of copies, a Mahoney type 1 poliovirus RNA standard was designed and produced using genetic engineering. This fragment, quantified using the Ribogreen method, was used in serial dilutions as an external standard. The method had a 7-log dynamic range (5 to 2 x 10(7)). PCR inhibitors were removed by extracting viral RNA (after virus concentration) using the RNeasy mini kit with added polyvinylpyrrolidone (PVP) and running the amplification reaction with a mixture containing PVP and T4 gene 32 protein. This real-time quantification of enterovirus RNA allows large numbers of samples to be screened. Its sensitivity, simplicity and reproducibility render it suitable as a screening method with which to characterize enteroviruses, the presence of infectious particles being subsequently confirmed by cell culture. 相似文献
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《Clinical and diagnostic virology》1998,9(2-3):125-133
Background: Environmental agents such as viruses have been identified as potentially important determinants of insulin-dependent diabetes mellitus (IDDM). Enterovirus infections, Coxsackievirus B especially, could be linked to the β cell damaging process and to the onset of clinical IDDM.Objectives: Enteroviral (EV) infection and β cell autoimmunity were studied in adult patients at the onset of IDDM.Study design: A total of 14 newly diagnosed-IDDM patients with ketosis or ketoacidosis were compared to, anteriorly diagnosed IDDM patients with metabolic decompensation, non-IDDM patients with metabolic decompensation and healthy adults. EV infection was studied by genomic RNA detection in whole blood using a RT-PCR assay. In order to assess the level of β cell autoantibodies at the time of the initial metabolic decompensation, serum specimens from IDDM patients were tested for GAD65 antibodies and islet cell antibodies (ICAs).Results: Coxsackie B3 or B4 virus genome was detected and genotyped in five of 14 (35.7%) newly diagnosed IDDM patients and in one of 12 (8%) patients in the course of IDDM. By contrast, none of the 12 non-IDDM patients and none of the 15 healthy adults was positive for enterovirus RNA detection in whole blood. Positive GAD65 antibodies and ICAs assays were not significantly correlated to a positive EV-RNA detection.Conclusion: The present study demonstrates that Coxsackie B virus RNA sequences can be detected in the peripheral blood from adult patients at the onset or in the course of IDDM and suggests that a Coxsackie B virus infection could initiate or accelerate β cell autoimmune damaging process. 相似文献
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Hua-Bing Zhao Guang-Ya Yin Guo-Ping Zhao Ai-Hua Huang Jun-Hong Wang Shuang-Feng Yang Hong-Sheng Gao Wei-Jun Kang 《Indian journal of microbiology》2014,54(1):80-86
Enteroviruses are found in most environments and cause several diseases in humans. Loop-mediated isothermal amplification (LAMP) was adapted and evaluated for the rapid detection of enteroviruses. Based on the highly conserved 5′ untranslated region (5′-UTR) of the human enteroviruses (HEVs), particularly human enterovirus A (HEV-A) and HEV-B, a set of universal primers was designed. The LAMP amplification was carried out under isothermal conditions at 61 °C, depending on the template concentration results were obtained within 45–90 min. The detection limits were found to be 101 copies of cloned enterovirus 71 fragments, more sensitive than conventional PCR. Nine water samples collected from drinking water sources during three seasons and 19 stool specimens collected from HFMD patients were analyzed. By using the LAMP assay, the majority of samples was tested positive, 9/9 (100 %) and 18/19 (94.7 %), respectively. LAMP is a practical method for the rapid detection of enteroviruses in environmental and clinical samples. 相似文献
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《Clinical and diagnostic virology》1998,9(2-3):141-143
Background: Although Enterovirus (EV) do not persist in the tissue, which is essential to maintain autoimmunity, they have been associated as the cause of chronic autoimmunity in some cases of insulin dependent diabetes mellitus (IDDM). Convincing reports, demonstrating persistent EV infections in the pancreases, are rare.Objectives: To determine the role of EV in IDDM, a mouse model was tested and in situ polymerase chain reaction (ISPCR) developed. The major problem of ISPCR are the high amounts of non-specific staining. In the current study we developed an ISPCR protocol which minimised non-specific staining and allowed the accurate localisation of the viral RNA in the tissue.Study design: Five mice were infected with coxsackievirus group B4, sacrificed 7 weeks later and the pancreases were harvested. The EV nucleic acid were localised and detected in the pancreases by ISPCR.Results: In the current study non-specific staining of ISPCR, due to DNA repair and diffuse artefacts, were minimised and the EV nucleic acids were localised in the β cells of the endocrine pancreases in all five diabetogenic mice.Conclusion: This study demonstrates an association of viral RNA with the development of diabetes in mice and the usefulness of ISPCR to determine the role of EV in IDDM. 相似文献
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Monpoeho S Maul A Bonnin C Patria L Ranarijaona S Billaudel S Ferré V 《Applied and environmental microbiology》2004,70(9):5434-5440
Sludges derived from wastewater treatment are foul-smelling, biologically unstable substances. As well as containing numerous pathogenic microorganisms, they also consist of organic matter that can be used as agricultural fertilizer. Legislation nevertheless requires sludges to be virologically tested prior to spreading by the counting of infectious enterovirus particles. This method, based on culture of enterovirus on BGM cells, is lengthy and not very sensitive. The aim of this study was to propose an alternative method of genome quantification for all enteroviruses that is applicable to verifying the elimination of viruses in complex samples such as sludges. Our complete protocol was compared to the official method, consisting of enterovirus enumeration with the most probable number of cythopathic unit (MPNCU) assay through the study of four stabilization procedures: liming, composting, heat treatment, and mesophile anaerobic digestion. Enterovirus quantities at the start of the stabilization procedures were between 37 and 288 MPNCU/g on the one scale and between 4 and 5 log genome copies/g on the other. It was shown that all procedures except mesophile anaerobic digestion were highly effective in the elimination of enterovirus particles and genomes in wastewater sludges. Reduction of viruses by mesophile anaerobic digestion was by only 1 log (infectious particles and genomes). In conclusion, stabilization processes can indeed be checked by virological quality control of sludges with gene amplification. However, the infectivity of genomes needs to be confirmed with cell culture or a correlation model if the virological risk inherent in the agricultural use of such sludges is to be fully addressed. 相似文献
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2009年云南省2株肠道病毒71型分离株全基因组序列遗传特性分析 总被引:1,自引:0,他引:1
对2009年云南省肠道病毒71型分离株KMM09和KM186-09进行全基因组序列测序,并与我国及其它国家流行的EV71基因型进行比较和进化分析。KMM09和KM186-09基因组长为7 409bp,编码2 193个氨基酸,VP1系统进化分析显示2009年云南分离株属于C4基因型的C4a亚型。在结构区,与其它基因型相比较,C基因型之间的核苷酸和氨基酸的同源性高于其它基因型;而在非结构区,C4与B基因型和CA16原型株G10同源性高于其它C基因亚型。通过RDP3重组软件和blast比对分析,发现EV71C4基因型与B3基因型,与CA16原型株G10的基因组在非结构区存在重组。EV71全基因组序列的比较和分析,对了解引起我国手足口病暴发或流行C4基因亚型EV71毒株的遗传特性具有重要意义。 相似文献
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Sequencing of porcine enterovirus groups II and III reveals unique features of both virus groups 总被引:2,自引:0,他引:2
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Krumbholz A Dauber M Henke A Birch-Hirschfeld E Knowles NJ Stelzner A Zell R 《Journal of virology》2002,76(11):5813-5821
The molecular classification of the porcine enterovirus (PEV) groups II and III was investigated. The sequence of the almost complete PEV-8 (group II) genome reveals that this virus has unique L and 2A gene regions. A reclassification of this group into a new picornavirus genus is suggested. PEV group III viruses are typical enteroviruses. They differ from other enteroviruses by a prolonged stem-loop D of the 5'-cloverleaf structure. 相似文献
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Mauro de Freitas Ortiz Karina Rodrigues Lorenzatto Bruna Renata Silva Corrêa Elgion Lucio Silva Loreto 《Genetica》2010,138(6):649-655
Transposable elements (TEs) comprise a significant fraction of the genome, and some models of the TE “life cycle” suggest
that, in the last phases of the cycle, TEs should be represented, in the genomes, by inactive and degenerated copies. In this
study, we analyzed, using a bioinformatics approach, the autonomous hAT elements and their derivatives (active non-autonomous, MITE relatives and degenerated copies) in 12 Drosophila genomes. We found 28 hAT elements that had derivatives. Most copies had features that suggested that they were active, while only a few degenerated
copies were found. Because hAT elements comprise an evolutionarily old superfamily, one should expect to find many degenerated copies within the genome,
although this was not observed in our study. These results suggest that primarily active copies of hAT elements are maintained in the euchromatic regions of the genome and that degenerated copies are removed from the genome
by natural selection. 相似文献
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《Clinical and diagnostic virology》1998,9(1):37-43
Background: The Amplicor™ HBV Monitor Test for quantitative determination of serum hepatitis B virus (HBV) DNA has recently been introduced. This assay is based on PCR and a non-radioactive hybridization and detection system on microwell plates.Objective: The performance of the Amplicor™ HBV Monitor Test was evaluated in a routine diagnostic laboratory. The Amplicor™ HBV Monoitor assay was compared to the Digene Hybrid Capture™ System HBV DNA assay for the quantitation of HBV in patient sera.Study design: Sensitivity and reproducibility were determined with 10-fold dilution series of two Eurohep HBV reference plasma specimens. Furthermore, 196 sera from 14 children with chronic HBV infection and interferon therapy were tested with both assays.Results: The detection limit was found to be 103 copies/ml with the Amplicor™ PCR assay compared to 106 to 107 copies/ml with the Digene™ hybridization assay. Both assays were quasi-linear over the measurable ranges. The new PCR assay proved to be very reliable. With the Amplicor™ PCR assay, 26.2% of the HBV DNA-positive clinical samples were found between 103 and 107 copies/ml and all of them tested below the detection limit with the hybridization assay.Conclusion: The Amplicor™ HBV Monitor Test shows excellent sensitivity and provides a valuable tool for the detection of HBV DNA in serum. It can be used for recognizing those patients who might benefit from antiviral therapy, for evaluation of the efficacy of anti-HBV therapy, and for validation of blood products. 相似文献
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Human enteroviruses consist of more than 60 serotypes, reflecting a wide range of evolutionary divergence. They have been genetically classified into four clusters on the basis of sequence homology in the coding region of the single-stranded RNA genome. To explore further the genetic relationships between human enteroviruses and to characterize the evolutionary mechanisms responsible for variation, previously sequenced genomes were subjected to detailed comparison. Bootstrap and genetic similarity analyses were used to systematically scan the alignments of complete genomic sequences. Bootstrap analysis provided evidence from an early recombination event at the junction of the 5' noncoding and coding regions of the progenitors of the current clusters. Analysis within the genetic clusters indicated that enterovirus prototype strains include intraspecies recombinants. Recombination breakpoints were detected in all genomic regions except the capsid protein coding region. Our results suggest that recombination is a significant and relatively frequent mechanism in the evolution of enterovirus genomes. 相似文献
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Shaukat S Angez M Alam MM Sharif S Khurshid A Malik F Rana MS Mahmood T Zaidi SS 《Applied and environmental microbiology》2012,78(12):4497-4500
Bovine enteroviruses belong to the family Picornaviridae. Little is known about their pathogenic potential; however, they cause asymptomatic infections in cattle and are excreted in feces. In the present study, viruses isolated from environmental samples were sequenced. According to phylogenetic analyses and standard picornavirus nomenclature, these isolates constitute a new type of bovine enterovirus serogroup A. 相似文献
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Dominik Mertz Abdulsalam Alawfi Jeffrey M. Pernica Candy Rutherford Kathy Luinstra Marek Smieja 《CMAJ》2015,187(17):1279-1284