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Sample records for evolutionarily significant virus

  1. An Evolutionarily Conserved Pathway Essential for Orsay Virus Infection of Caenorhabditis elegans

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    Hongbing Jiang

    2017-09-01

    Full Text Available Many fundamental biological discoveries have been made in Caenorhabditis elegans. The discovery of Orsay virus has enabled studies of host-virus interactions in this model organism. To identify host factors critical for Orsay virus infection, we designed a forward genetic screen that utilizes a virally induced green fluorescent protein (GFP reporter. Following chemical mutagenesis, two Viro (virus induced reporter off mutants that failed to express GFP were mapped to sid-3, a nonreceptor tyrosine kinase, and B0280.13 (renamed viro-2, an ortholog of human Wiskott-Aldrich syndrome protein (WASP. Both mutants yielded Orsay virus RNA levels comparable to that of the residual input virus, suggesting that they are not permissive for Orsay virus replication. In addition, we demonstrated that both genes affect an early prereplication stage of Orsay virus infection. Furthermore, it is known that the human ortholog of SID-3, activated CDC42-associated kinase (ACK1/TNK2, is capable of phosphorylating human WASP, suggesting that VIRO-2 may be a substrate for SID-3 in C. elegans. A targeted RNA interference (RNAi knockdown screen further identified the C. elegans gene nck-1, which has a human ortholog that interacts with TNK2 and WASP, as required for Orsay virus infection. Thus, genetic screening in C. elegans identified critical roles in virus infection for evolutionarily conserved genes in a known human pathway.

  2. ELISA: Structure-Function Inferences based on statistically significant and evolutionarily inspired observations

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    DeLisi Charles

    2003-09-01

    Full Text Available Abstract The problem of functional annotation based on homology modeling is primary to current bioinformatics research. Researchers have noted regularities in sequence, structure and even chromosome organization that allow valid functional cross-annotation. However, these methods provide a lot of false negatives due to limited specificity inherent in the system. We want to create an evolutionarily inspired organization of data that would approach the issue of structure-function correlation from a new, probabilistic perspective. Such organization has possible applications in phylogeny, modeling of functional evolution and structural determination. ELISA (Evolutionary Lineage Inferred from Structural Analysis, http://romi.bu.edu/elisa is an online database that combines functional annotation with structure and sequence homology modeling to place proteins into sequence-structure-function "neighborhoods". The atomic unit of the database is a set of sequences and structural templates that those sequences encode. A graph that is built from the structural comparison of these templates is called PDUG (protein domain universe graph. We introduce a method of functional inference through a probabilistic calculation done on an arbitrary set of PDUG nodes. Further, all PDUG structures are mapped onto all fully sequenced proteomes allowing an easy interface for evolutionary analysis and research into comparative proteomics. ELISA is the first database with applicability to evolutionary structural genomics explicitly in mind. Availability: The database is available at http://romi.bu.edu/elisa.

  3. Epstein-Barr virus microRNAs are evolutionarily conserved and differentially expressed.

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    Xuezhong Cai

    2006-03-01

    Full Text Available The pathogenic lymphocryptovirus Epstein-Barr virus (EBV is shown to express at least 17 distinct microRNAs (miRNAs in latently infected cells. These are arranged in two clusters: 14 miRNAs are located in the introns of the viral BART gene while three are located adjacent to BHRF1. The BART miRNAs are expressed at high levels in latently infected epithelial cells and at lower, albeit detectable, levels in B cells. In contrast to the tissue-specific expression pattern of the BART miRNAs, the BHRF1 miRNAs are found at high levels in B cells undergoing stage III latency but are essentially undetectable in B cells or epithelial cells undergoing stage I or II latency. Induction of lytic EBV replication was found to enhance the expression of many, but not all, of these viral miRNAs. Rhesus lymphocryptovirus, which is separated from EBV by > or =13 million years of evolution, expresses at least 16 distinct miRNAs, seven of which are closely related to EBV miRNAs. Thus, lymphocryptovirus miRNAs are under positive selection and are likely to play important roles in the viral life cycle. Moreover, the differential regulation of EBV miRNA expression implies distinct roles during infection of different human tissues.

  4. A nuclear DNA perspective on delineating evolutionarily significant lineages in polyploids: the case of the endangered shortnose sturgeon (Acipenser brevirostrum)

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    King, Timothy L.; Henderson, Anne P.; Kynard, Boyd E.; Kieffer, Micah C.; Peterson, Douglas L.; Aunins, Aaron W.; Brown, Bonnie L.

    2014-01-01

    The shortnose sturgeon, Acipenser brevirostrum, oft considered a phylogenetic relic, is listed as an “endangered species threatened with extinction” in the US and “Vulnerable” on the IUCN Red List. Effective conservation of A. brevirostrum depends on understanding its diversity and evolutionary processes, yet challenges associated with the polyploid nature of its nuclear genome have heretofore limited population genetic analysis to maternally inherited haploid characters. We developed a suite of polysomic microsatellite DNA markers and characterized a sample of 561 shortnose sturgeon collected from major extant populations along the North American Atlantic coast. The 181 alleles observed at 11 loci were scored as binary loci and the data were subjected to multivariate ordination, Bayesian clustering, hierarchical partitioning of variance, and among-population distance metric tests. The methods uncovered moderately high levels of gene diversity suggesting population structuring across and within three metapopulations (Northeast, Mid-Atlantic, and Southeast) that encompass seven demographically discrete and evolutionarily distinct lineages. The predicted groups are consistent with previously described behavioral patterns, especially dispersal and migration, supporting the interpretation that A. brevirostrum exhibit adaptive differences based on watershed. Combined with results of prior genetic (mitochondrial DNA) and behavioral studies, the current work suggests that dispersal is an important factor in maintaining genetic diversity in A. brevirostrum and that the basic unit for conservation management is arguably the local population.

  5. GB Virus C Infection: Clinical Significance

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    Xiang Wei Meng

    1999-01-01

    Full Text Available GB virus C (GBV-C RNA positivity rates were examined in serum specimens from 231 patients with liver disease (23 patients with hepatitis B, 175 patients with hepatitis C, five patients with hepatitis B virus plus hepatitis C virus coinfection, and 28 patients with non-A, non-B, non-C hepatitis to clarify the clinical significance of this virus. GBV-C RNA was detected in none of 12 patients with fulminant hepatitis, one of two patients with acute hepatitis positive for hepatitis B surface antigen and one of four patients with acute non-A, non-B, non-C hepatitis. Pathogenetic involvement of GBV-C was suspected in some patients in the latter group. Among patients with the non-B, non-C type of chronic disease, one of seven with cirrhosis (14% and none with chronic hepatitis or hepatocellular carcinoma were GBV-C-positive. In chronic hepatitis C patients who had received interferon treatment, no difference was found in clinical findings, alanine aminotransferase (ALT concentrations, histology or response to interferon between 11 patients who were GBV-C RNA-positive and 101 patients who were GBV-C RNA-negative. Moreover, changes in ALT after interferon therapy showed no relation to positivity for GBV-C RNA. On the basis of these findings, GBV-C appears to be an unlikely cause of initiation or progression of chronic hepatic diseases.

  6. Genetic diversity and population structure of the pelagic thresher shark (Alopias pelagicus) in the Pacific Ocean: evidence for two evolutionarily significant units.

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    Cardeñosa, Diego; Hyde, John; Caballero, Susana

    2014-01-01

    There has been an increasing concern about shark overexploitation in the last decade, especially for open ocean shark species, where there is a paucity of data about their life histories and population dynamics. Little is known regarding the population structure of the pelagic thresher shark, Alopias pelagicus. Though an earlier study using mtDNA control region data, showed evidence for differences between eastern and western Pacific populations, the study was hampered by low sample size and sparse geographic coverage, particularly a lack of samples from the central Pacific. Here, we present the population structure of Alopias pelagicus analyzing 351 samples from six different locations across the Pacific Ocean. Using data from mitochondrial DNA COI sequences and seven microsatellite loci we found evidence of strong population differentiation between western and eastern Pacific populations and evidence for reciprocally monophyly for organelle haplotypes and significant divergence of allele frequencies at nuclear loci, suggesting the existence of two Evolutionarily Significant Units (ESU) in the Pacific Ocean. Interestingly, the population in Hawaii appears to be composed of both ESUs in what seems to be clear sympatry with reproductive isolation. These results may indicate the existence of a new cryptic species in the Pacific Ocean. The presence of these distinct ESUs highlights the need for revised management plans for this highly exploited shark throughout its range.

  7. Genetic diversity and population structure of the pelagic thresher shark (Alopias pelagicus in the Pacific Ocean: evidence for two evolutionarily significant units.

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    Diego Cardeñosa

    Full Text Available There has been an increasing concern about shark overexploitation in the last decade, especially for open ocean shark species, where there is a paucity of data about their life histories and population dynamics. Little is known regarding the population structure of the pelagic thresher shark, Alopias pelagicus. Though an earlier study using mtDNA control region data, showed evidence for differences between eastern and western Pacific populations, the study was hampered by low sample size and sparse geographic coverage, particularly a lack of samples from the central Pacific. Here, we present the population structure of Alopias pelagicus analyzing 351 samples from six different locations across the Pacific Ocean. Using data from mitochondrial DNA COI sequences and seven microsatellite loci we found evidence of strong population differentiation between western and eastern Pacific populations and evidence for reciprocally monophyly for organelle haplotypes and significant divergence of allele frequencies at nuclear loci, suggesting the existence of two Evolutionarily Significant Units (ESU in the Pacific Ocean. Interestingly, the population in Hawaii appears to be composed of both ESUs in what seems to be clear sympatry with reproductive isolation. These results may indicate the existence of a new cryptic species in the Pacific Ocean. The presence of these distinct ESUs highlights the need for revised management plans for this highly exploited shark throughout its range.

  8. Insect-Specific Virus Discovery: Significance for the Arbovirus Community

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    Bethany G. Bolling

    2015-09-01

    Full Text Available Arthropod-borne viruses (arboviruses, especially those transmitted by mosquitoes, are a significant cause of morbidity and mortality in humans and animals worldwide. Recent discoveries indicate that mosquitoes are naturally infected with a wide range of other viruses, many within taxa occupied by arboviruses that are considered insect-specific. Over the past ten years there has been a dramatic increase in the literature describing novel insect-specific virus detection in mosquitoes, which has provided new insights about viral diversity and evolution, including that of arboviruses. It has also raised questions about what effects the mosquito virome has on arbovirus transmission. Additionally, the discovery of these new viruses has generated interest in their potential use as biological control agents as well as novel vaccine platforms. The arbovirus community will benefit from the growing database of knowledge concerning these newly described viral endosymbionts, as their impacts will likely be far reaching.

  9. An Evolutionarily Informed Education Science

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    Geary, David C.

    2008-01-01

    Schools are a central interface between evolution and culture. They are the contexts in which children learn the evolutionarily novel abilities and knowledge needed to function as adults in modern societies. Evolutionary educational psychology is the study of how an evolved bias in children's learning and motivational systems influences their…

  10. Viruses of Fish: An Overview of Significant Pathogens

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    Mark Crane

    2011-10-01

    Full Text Available The growing global demand for seafood together with the limited capacity of the wild-capture sector to meet this demand has seen the aquaculture industry continue to grow around the world. A vast array of aquatic animal species is farmed in high density in freshwater, brackish and marine systems where they are exposed to new environments and potentially new diseases. On-farm stresses may compromise their ability to combat infection, and farming practices facilitate rapid transmission of disease. Viral pathogens, whether they have been established for decades or whether they are newly emerging as disease threats, are particularly challenging since there are few, if any, efficacious treatments, and the development of effective viral vaccines for delivery in aquatic systems remains elusive. Here, we review a few of the more significant viral pathogens of finfish, including aquabirnaviruses and infectious hematopoietic necrosis virus which have been known since the first half of the 20th century, and more recent viral pathogens, for example betanodaviruses, that have emerged as aquaculture has undergone a dramatic expansion in the past few decades.

  11. Clinical significance of occult hepatitis B virus infection.

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    Romero, Miriam; Madejón, Antonio; Fernández-Rodríguez, Conrado; García-Samaniego, Javier

    2011-03-28

    Occult hepatitis B virus (HBV) infection (OBI) is defined as the presence of HBV DNA in the liver (with or without detectable HBV DNA in serum) for individuals testing HBV surface antigen negative. Until recently, the clinical effect of OBI was unclear on the progression of liver disease; on the development of hepatocellular carcinoma; and on the risk for reactivation or transmission of HBV infection. Several studies suggest a high prevalence of OBI among patients with cryptogenic chronic liver disease, but its role in the progression to cirrhosis remains unclear. Although OBI has been well documented in human immunodeficiency virus (HIV)-positive patients, especially among those coinfected with hepatitis C virus, further studies are needed to determine its current clinical impact in HIV setting.

  12. Viruses and their significance in agricultural and horticultural crops in Finland

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    E. TAPIO

    2008-12-01

    Full Text Available This paper reviews the plant viruses and virus vectors that have been detected in agricultural and horticultural crop plants and some weeds in Finland. The historical and current importance of virus diseases and the methods used for controlling them in cereals, potato, berry plants, fruit trees, ornamental plants and vegetables are discussed. Plant viruses have been intensely studied in Finland over 40 years. Up to date, 44 plant virus species have been detected, and many tentatively identified virus-es are also reported. Control of many virus diseases has been significantly improved. This has been achieved mainly through changes in cropping systems, production of healthy seed potatoes and healthy stocks of berry plants, fruit trees and ornamental plants in the institutes set up for such production, and improved hygiene. At the present, barley yellow dwarf luteovirus, potato Y potyvirus and potato mop-top furovirus are considred to be economically the most harmful plant viruses in Finland.

  13. Myxoma virus is a novel oncolytic virus with significant antitumor activity against experimental human gliomas.

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    Lun, Xueqing; Yang, Wenqing; Alain, Tommy; Shi, Zhong-Qiao; Muzik, Huong; Barrett, John W; McFadden, Grant; Bell, John; Hamilton, Mark G; Senger, Donna L; Forsyth, Peter A

    2005-11-01

    Myxoma virus, a poxvirus previously considered rabbit specific, can replicate productively in a variety of human tumor cells in culture. The purpose of this study was to determine if there was efficacy or toxicities of this oncolytic virus against experimental models of human malignant gliomas in vitro, in vivo, and ex vivo in malignant glioma specimens. In vitro, the majority of glioma cell lines tested (7 of 8, 87.5%) were fully permissive for myxoma virus replication and killed by infection. In vivo, intracerebral (i.c.) myxoma virus inoculation was well tolerated and produced only minimal focal inflammatory changes at the site of viral inoculation. U87 and U251 orthotopic xenograft models were used to assess myxoma virus efficacy in vivo. A single intratumoral injection of myxoma virus dramatically prolonged median survival compared with treatment with UV-inactivated myxoma virus. Median survival was not reached in myxoma virus-treated groups versus 47.3 days (U87; P = 0.0002) and 50.7 days (U251; P = 0.0027) in UV-inactivated myxoma virus-treated groups. Most myxoma virus-treated animals (12 of 13, 92%) were alive and apparently "cured" when the experiment was finished (>130 days). Interestingly, we found a selective and long-lived myxoma virus infection in gliomas in vivo. This is the first demonstration of the oncolytic activity of myxoma virus in vivo. The nonpathogenic nature of myxoma virus outside of the rabbit host, its capacity to be genetically modified, its ability to produce a long-lived infection in human tumor cells, and the lack of preexisting antibodies in the human population suggest that myxoma virus may be an attractive oncolytic agent against human malignant glioma.

  14. Myxoma Virus Is a Novel Oncolytic Virus with Significant Antitumor Activity against Experimental Human Gliomas

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    Lun, Xueqing; Yang, Wenqing; Alain, Tommy; Shi, Zhong-Qiao; Muzik, Huong; Barrett, John W.; McFadden, Grant; Bell, John; Hamilton, Mark G.; Senger, Donna L.; Forsyth, Peter A.

    2005-01-01

    Myxoma virus, a poxvirus previously considered rabbit specific, can replicate productively in a variety of human tumor cells in culture. The purpose of this study was to determine if there was efficacy or toxicities of this oncolytic virus against experimental models of human malignant gliomas in vitro, in vivo, and ex vivo in malignant glioma specimens. In vitro, the majority of glioma cell lines tested (7 of 8, 87.5%) were fully permissive for myxoma virus replication and killed by infectio...

  15. Common mutations of hepatitis B virus and their clinical significance

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    HU Airong

    2016-06-01

    Full Text Available Hepatitis B virus (HBV tends to mutate easily due to its special structure and life cycle. Mutation changes the biological behavior of HBV and its sensitivity to antiviral drugs and even affects therapeutic effect and accelerate disease progression. The point mutations are commonly see in the pre-S/S open reading frame (ORF, which may be associated with immune escape and occult HBV infection. The G1896A mutation is often observed in the pre-C/C-ORF and is associated with the development of HBeAg-negative chronic hepatitis B (CHB, hepatocellular carcinoma (HCC, and severe chronic hepatitis (liver failure. The mutations in P-ORF mainly occur in the reverse transcriptase (RT domain and are closely related to the resistance to nucleos(tide analogues. The A1762T and G1764A mutations occur in the basal core promoter (BCP, which overlaps with X-ORF, and may be associated with HBeAg-negative CHB, HCC, and severe chronic hepatitis (liver failure. Clarification of the association between these mutations and diseases helps to develop tailor-made diagnostic and therapeutic regimens for patients with HBV infection.

  16. Expression of evolutionarily novel genes in tumors

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    A. P. Kozlov

    2016-01-01

    The evolutionarily novel genes originated through different molecular mechanisms are expressed in tumors. Sometimes the expression of evolutionarily novel genes in tumors is highly specific. Moreover positive selection of many human tumor-related genes in primate lineage suggests their involvement in the origin of new functions beneficial to organisms. It is suggested to consider the expression of evolutionarily young or novel genes in tumors as a new biological phenomenon, a phenomenon of TS...

  17. Prevalence and prognostic significance of infection with TT virus in patients infected with human immunodeficiency virus

    DEFF Research Database (Denmark)

    Christensen, JK; Eugen-Olsen, Jesper; Sørensen, M

    2000-01-01

    No clear association between human disease and TT virus (TTV) has been documented. A possible pathogenic role of TTV was investigated in patients infected with human immunodeficiency virus (HIV). TTV serum concentrations were estimated in 185 HIV-infected patients by dilution polymerase chain rea...... TTV viremia (Psuspected to be an opportunistic pathogen with an independent influence on HIV progression....

  18. Clinical significance of different virus load of human bocavirus in patients with lower respiratory tract infection.

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    Jiang, Wujun; Yin, Fang; Zhou, Weifang; Yan, Yongdong; Ji, Wei

    2016-02-01

    To assess the impact of human bocavirus (HBoV) virus load on epidemiologic and clinical characteristics in children with lower respiratory tract infection (LRTI). Clinical records of a total of 654 patients with HBoV infection during January 2013 and December 2014 were retrospectively reviewed. Patients with high HBoV virus load infection had a similar age distribution with the total HBoV infection, which had a peak age group of 6-24 months. Patients with high virus load are significantly younger (P infection was found significantly more frequently among patients with low virus load than those with high virus load (57.0% vs 38.9%; P infections are found in an important proportion of the hospitalized children with respiratory illnesses (8.85% in our series). A high HBoV virus load could be an etiologic agent for LRTI, which may lead to more severe lower respiratory tract symptom and severe disease.

  19. Thioredoxins in evolutionarily primitive organisms

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    Buchanan, B. B.

    1986-01-01

    Thioredoxins are low molecular weight redox proteins, alternating between the S-S (oxidized) and SH (reduced) states, that function in a number of biochemical processes, including DNA synthesis, DNA replication, and enzyme regulation. Until recently, reduced ferredoxin was known to serve as the source of reducing power for the reduction of thioredoxins only in oxygenic photosynthetic cells. In all other organisms, the source of hydrogen (electrons) for thioredoxin reduction was considered to be NADPH. It was found that Clostridium pasteurianum, an anaerobic organism normally living in the soil unexposed to light, resembles photosynthetic cells in using ferredoxin for the reduction of thioredoxin. The results reveal the existence of a pathway in which ferredoxin, provides the reducing power for the reduction of thioredoxin via the flavoprotein enzyme, ferredoxinthioredoxin reductase. In related studies, it was found that Chromatium vinosum, an anaerobic photosynthetic purple sulfur bacterium, resembles evolutionarily more advanced micro-organisms in having an NADP-thioredoxin system composed of a single thioredoxin which is reduced by NADPH via NADP-thioredoxin reductase. The adoption of the NADP-thioredoxin system by Chromatium seems appropriate in view of evidence tha the organi sm utilizes ATP-driven reverse electron transport. Finally, results of research directed towards the identification of target enzymes of the ferredoxin/thioredoxin system in a cyanobacterium (Nostoc muscorum), show that thioredoxin-linked photosynthetic enzymes of cyanobateria are similar to those of chloroplasts. It now seems that the ferredoxin/thioredoxin system functions in regulating CO2 assimilation via the reductive pentose phosphate cycle in oxygenic but not anoxygenic photosynthetic cells.

  20. Respiratory syncytial virus hospitalisation trends in children with haemodynamically significant heart disease, 1997-2012.

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    Chu, Patricia Y; Hornik, Christoph P; Li, Jennifer S; Campbell, Michael J; Hill, Kevin D

    2017-01-01

    The aim of the study was to evaluate the trends in respiratory syncytial virus-related hospitalisations and associated outcomes in children with haemodynamically significant heart disease in the United States of America. Study design The Kids' Inpatient Databases (1997-2012) were used to estimate the incidence of respiratory syncytial virus hospitalisation among children ⩽24 months with or without haemodynamically significant heart disease. Weighted multivariable logistic regression and chi-square tests were used to evaluate the trends over time and factors associated with hospitalisation, comparing eras before and after publication of the 2003 American Academy of Pediatrics palivizumab immunoprophylaxis guidelines. Secondary outcomes included in-hospital mortality, morbidity, length of stay, and cost. Overall, 549,265 respiratory syncytial virus-related hospitalisations were evaluated, including 2518 (0.5%) in children with haemodynamically significant heart disease. The incidence of respiratory syncytial virus hospitalisation in children with haemodynamically significant heart disease decreased by 36% when comparing pre- and post-palivizumab guideline eras versus an 8% decline in children without haemodynamically significant heart disease (prespiratory syncytial virus-associated mortality (4.9 versus 0.1%, prespiratory syncytial virus hospitalisation in 2009 was $58,166 (95% CI:$46,017, $70,315). These data provide stakeholders with a means to evaluate the cost-utility of various immunoprophylaxis strategies.

  1. Large-scale nucleotide sequence alignment and sequence variability assessment to identify the evolutionarily highly conserved regions for universal screening PCR assay design: an example of influenza A virus.

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    Nagy, Alexander; Jiřinec, Tomáš; Černíková, Lenka; Jiřincová, Helena; Havlíčková, Martina

    2015-01-01

    The development of a diagnostic polymerase chain reaction (PCR) or quantitative PCR (qPCR) assay for universal detection of highly variable viral genomes is always a difficult task. The purpose of this chapter is to provide a guideline on how to align, process, and evaluate a huge set of homologous nucleotide sequences in order to reveal the evolutionarily most conserved positions suitable for universal qPCR primer and hybridization probe design. Attention is paid to the quantification and clear graphical visualization of the sequence variability at each position of the alignment. In addition, specific problems related to the processing of the extremely large sequence pool are highlighted. All of these steps are performed using an ordinary desktop computer without the need for extensive mathematical or computational skills.

  2. The prognostic significance of virus-associated changes in grade 1 cervical intra-epithelial neoplasia

    DEFF Research Database (Denmark)

    Bagi, P; Worning, A M; Nordsten, M

    1987-01-01

    Virus-associated changes of the cervix uteri were assessed in patients treated for grade 1 cervical intra-epithelial neoplasia (CIN). Of 106 patients evaluated, 67 (63%) had virus-associated changes. The patients were treated without regard to the presence/absence of virus-associated changes. In 26...... patients the treatment was unsuccessful (persistence, recurrence, or progression of the neoplasia). The frequency of treatment failure was 33% in patients with, and 10% in patients without virus-associated changes (p less than 0.025). It is recommended that patients with CIN 1 and virus-associated changes...

  3. [Effects of global climate change on the ecological characteristics and biogeochemical significance of marine viruses--A review].

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    Yang, Yunlan; Cai, Lanlan; Zhang, Rui

    2015-09-04

    As the most abundance biological agents in the oceans, viruses can influence the physiological and ecological characteristics of host cells through viral infections and lysis, and affect the nutrient and energy cycles of the marine food chain. Thus, they are the major players in the ocean biogeochemical processes. The problems caused by global climate changes, such as sea-surface warming, acidification, nutrients availability, and deoxygenation, have the potential effects on marine viruses and subsequently their ecological and biogeochemical function in the ocean. Here, we reviewed the potential impacts of global climate change on the ecological characteristics (e. g. abundance, distribution, life cycle and the host-virus interactions) and biogeochemical significance (e. g. carbon cycling) of marine viruses. We proposed that marine viruses should not be ignored in the global climate change study.

  4. The Vpr gene polymorphism of human immunodeficiency virus type 1 in China and its clinical significance.

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    Chen, Xia; Zheng, Yuhuang; Li, Hui; Mamadou, Diallo; Zhang, Chunying; He, Yan; Zhou, Huaying; Chen, Zi; Liu, Meng

    2011-07-01

    Recent studies have explored that mutated Human immunodeficiency virus type 1(HIV-1) Vpr genes likely influence clinical manifestations of HIV infected patients. However, the relationship between the mutation sites on HIV Vpr gene and subsequent function changes is still not clear. In this study we investigated such relationship in analyzing the Vpr genes of HIV-1 viruses isolated from 208 HIV-1 infected patients from different regions in China. Reverse transcription polymerase chain reaction (RT-PCR) and nested PCR were used to amplify HIV-1 Vpr gene extracted from plasma of 208 HIV-1 infected patients and 153 isolates displayed the target gene sequences. Biological analysis software analyzed the deduced amino acid sequence, and identified the characteristics of the polymorphism of HIV-1 Vpr gene and its clinical significance. Results show the sequence subtypes as follows: CRF01-AE is 51.63%, subtype C is 24.84%, ubtype B is 17.65%, CRF03-AB is 3.92% and CRF08-BC is 1.31%. This paper revealed for the first time the HIV-1 Vpr gene polymorphism in HIV-1 positive individuals in China.: the subtype CRF01-AE is the main Vpr gene subtype in this region. The mutations in the C-terminal were more obvious than those observed in the N-terminal. It was also discovered that in the 77th position, 84.3% of the 153 amino acid sequences were glutamine (Q), which differ from overseas reports. Our data showed that the mutations 63, 70, 85, 86, 89 and 94 of the Vpr gene were possibly correlated with the clinical manifestations of the HIV-1 infected individuals.

  5. Evolutionarily conserved sequences on human chromosome 21

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    Frazer, Kelly A.; Sheehan, John B.; Stokowski, Renee P.; Chen, Xiyin; Hosseini, Roya; Cheng, Jan-Fang; Fodor, Stephen P.A.; Cox, David R.; Patil, Nila

    2001-09-01

    Comparison of human sequences with the DNA of other mammals is an excellent means of identifying functional elements in the human genome. Here we describe the utility of high-density oligonucleotide arrays as a rapid approach for comparing human sequences with the DNA of multiple species whose sequences are not presently available. High-density arrays representing approximately 22.5 Mb of nonrepetitive human chromosome 21 sequence were synthesized and then hybridized with mouse and dog DNA to identify sequences conserved between humans and mice (human-mouse elements) and between humans and dogs (human-dog elements). Our data show that sequence comparison of multiple species provides a powerful empiric method for identifying actively conserved elements in the human genome. A large fraction of these evolutionarily conserved elements are present in regions on chromosome 21 that do not encode known genes.

  6. A belief-based evolutionarily stable strategy.

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    Deng, Xinyang; Wang, Zhen; Liu, Qi; Deng, Yong; Mahadevan, Sankaran

    2014-11-21

    As an equilibrium refinement of the Nash equilibrium, evolutionarily stable strategy (ESS) is a key concept in evolutionary game theory and has attracted growing interest. An ESS can be either a pure strategy or a mixed strategy. Even though the randomness is allowed in mixed strategy, the selection probability of pure strategy in a mixed strategy may fluctuate due to the impact of many factors. The fluctuation can lead to more uncertainty. In this paper, such uncertainty involved in mixed strategy has been further taken into consideration: a belief strategy is proposed in terms of Dempster-Shafer evidence theory. Furthermore, based on the proposed belief strategy, a belief-based ESS has been developed. The belief strategy and belief-based ESS can reduce to the mixed strategy and mixed ESS, which provide more realistic and powerful tools to describe interactions among agents. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Expression Profiles of Bovine Adeno-Associated Virus and Avian Adeno-Associated Virus Display Significant Similarity to That of Adeno-Associated Virus Type 5

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    Qiu, Jianming; Cheng, Fang; Pintel, David J.

    2006-01-01

    We present the first detailed expression profiles of nonprimate-derived adeno-associated viruses, namely, bovine adeno-associated virus (B-AAV) and avian adeno-associated virus (A-AAV), which were obtained after the infection of cell lines derived from their natural hosts. In general, the profiles of B-AAV and A-AAV were quite similar to that of AAV5; however, both exhibited features found for AAV2 as well. Like adeno-associated virus type 5 (AAV5), B-AAV and A-AAV utilized an internal polyad...

  8. Prognostic significance of Epstein-Barr virus (EBV) infection in Hodgkin lymphoma patients.

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    Myriam, Ben Dhiab; Sonia, Ziadi; Hanene, Saad; Teheni, Louhichi; Mounir, Trimeche

    2017-03-01

    The prognostic significance of Epstein-Barr virus (EBV) infection in Hodgkin lymphoma (HL) is still controversial. In this work we sought to examine the prognostic differences between EBV-positive and -negative HL through a series of 131 cases from Tunisia. The status of EBV was assessed by EBV-encoded RNA (EBER) in situ hybridization. Results were correlated to patients' characteristics and outcome. EBV was detected in the malignant cells in 62 of 131 HL cases (47.3%). EBV-positive HL was associated with extreme age classes (≤15 and > 45 years; p = 0.0001), male gender (p = 0.008), mixed cellularity histologic subtype (p = 0.03), and inversely with leukocytosis (white blood cells ≥15000/mm3) (p = 0.004) and bulky mediastinum (mediastinal-thoracic ratio≥ 0.35) (p = 0.0001). On analysis of all patients, no significant difference between survival rates was found between EBV-positive and EBV-negative HL. In contrast, subgroups analysis revealed a negative effect of EBV infection in terms of overall survival in patients with Ann Arbor stages I/II (p = 0.03) and nodular sclerosis HL subgroup (p = 0.01), and in terms of event free survival in patients with mediastinal-thoracic ratio less than 0.35 (p = 0.03). These results suggest that EBV infection affects the survival of particular subgroups of HL, especially those with early-stage of the disease. Copyright © 2016. Published by Elsevier Ltd.

  9. Viruses in wild European fishes and their significance for aquaculture, with special emphasis on viral haemorrhagic septicamia virus

    DEFF Research Database (Denmark)

    Skall, Helle Frank

    2004-01-01

    VHS virus fra nogle af de inficerede fisk. Ligeledes er VHS i Atlantisk laks ikke af stor bekymring, selvom naturlig infektion med VHSV i opdrættet Atlantisk laks er blevet observeret i Canada. For opdræt af marine fisk er situationen anderledes, da adskillige af de marine VHSV isolater er blevet vist......Viral hæmorrhagisk septikæmi virus (VHSV) er en af de vigtigste virale patogener i opdrættet regnbueørred (Oncorhynchus mykiss) i Europa. Det Europæiske Fællesskabs (EU's) fiskehelse lovgivning (Direktiv 91/67/EEC) opregner VHS som en kategori 2 sygdom, hvilket er defineret som en sygdom med stor...... økonomisk betydning for Fællesskabet. VHSV er i det sidste 1½ årti blevet isoleret fra et stadig stigende antal fritlevende marine fiskearter. Indtil nu er VHSV blevet isoleret fra 46 forskellige fiskearter på den nordlige halvkugle (USA, Canada, Japan og Europa), heraf 15 forskellige fritlevende marine...

  10. Significance of the oligosaccharides of the porcine reproductive and respiratory syndrome virus glycoproteins GP2a and GP5 for infectious virus production

    NARCIS (Netherlands)

    Wissink, E.H.J.; Kroese, M.V.; Maneschijn-Bonsing, J.G.; Meulenberg, J.J.; Rijn, van P.A.; Rijsewijk, F.A.M.; Rottier, P.J.M.

    2004-01-01

    The arterivirus porcine reproductive and respiratory syndrome virus (PRRSV) contains four glycoproteins, GP2a, GP3, GP4 and GP5, the functions of which are still largely unresolved. In this study, the significance of the N-glycosylation of the GP2a and GP5 proteins of PRRSV strain LV was

  11. In vitro Studies of Sandfly Fever Viruses and Their Potential Significance for Vaccine Development.

    Science.gov (United States)

    1980-02-01

    agglutinin (galactose), ulex lectins (fucose), or limulin (sialic acid). Sandfly viruses or their envelope antigens could then be purified from non...limulin, which binds to slalic acid; and ulex lectin (anti-H lectin) which binds to fucose, would not recognize viral glycoproteins or particles, but

  12. Presence and significance of TT virus in Danish patients on maintenance hemodialysis

    DEFF Research Database (Denmark)

    Boysen, T.; Christensen, J. K.; Madsen, C. D.

    2003-01-01

    Objectives: To determine the prevalence of TT virus (TTV) in a population of Danish hemodialysis patients and evaluate possible relations between TTV infection and elevated levels of C-reactive protein (CRP) and hypo-response to treatment with erythropoietin (EPO). Material and Methods: Patients ...

  13. Evolutionarily conserved herpesviral protein interaction networks.

    Directory of Open Access Journals (Sweden)

    Even Fossum

    2009-09-01

    Full Text Available Herpesviruses constitute a family of large DNA viruses widely spread in vertebrates and causing a variety of different diseases. They possess dsDNA genomes ranging from 120 to 240 kbp encoding between 70 to 170 open reading frames. We previously reported the protein interaction networks of two herpesviruses, varicella-zoster virus (VZV and Kaposi's sarcoma-associated herpesvirus (KSHV. In this study, we systematically tested three additional herpesvirus species, herpes simplex virus 1 (HSV-1, murine cytomegalovirus and Epstein-Barr virus, for protein interactions in order to be able to perform a comparative analysis of all three herpesvirus subfamilies. We identified 735 interactions by genome-wide yeast-two-hybrid screens (Y2H, and, together with the interactomes of VZV and KSHV, included a total of 1,007 intraviral protein interactions in the analysis. Whereas a large number of interactions have not been reported previously, we were able to identify a core set of highly conserved protein interactions, like the interaction between HSV-1 UL33 with the nuclear egress proteins UL31/UL34. Interactions were conserved between orthologous proteins despite generally low sequence similarity, suggesting that function may be more conserved than sequence. By combining interactomes of different species we were able to systematically address the low coverage of the Y2H system and to extract biologically relevant interactions which were not evident from single species.

  14. Significant Growth Inhibition of Canine Mammary Carcinoma Xenografts following Treatment with Oncolytic Vaccinia Virus GLV-1h68

    Science.gov (United States)

    Gentschev, Ivaylo; Ehrig, Klaas; Donat, Ulrike; Hess, Michael; Rudolph, Stephan; Chen, Nanhai; Yu, Yong A.; Zhang, Qian; Bullerdiek, Jörn; Nolte, Ingo; Stritzker, Jochen; Szalay, Aladar A.

    2010-01-01

    Canine mammary carcinoma is a highly metastatic tumor that is poorly responsive to available treatment. Therefore, there is an urgent need to identify novel agents for therapy of this disease. Recently, we reported that the oncolytic vaccinia virus GLV-1h68 could be a useful tool for therapy of canine mammary adenoma in vivo. In this study we analyzed the therapeutic effect of GLV-1h68 against canine mammary carcinoma. Cell culture data demonstrated that GLV-1h68 efficiently infected and destroyed cells of the mammary carcinoma cell line MTH52c. Furthermore, after systemic administration, this attenuated vaccinia virus strain primarily replicated in canine tumor xenografts in nude mice. Finally, infection with GLV-1h68 led to strong inflammatory and oncolytic effects resulting in significant growth inhibition of the tumors. In summary, the data showed that the GLV-1h68 virus strain has promising potential for effective treatment of canine mammary carcinoma. PMID:20631910

  15. Coronavirus in Pigs: Significance and Presentation of Swine Epidemic Diarrhea Virus (PEDV in Colombia

    Directory of Open Access Journals (Sweden)

    Ricardo Piñeros

    2015-05-01

    Full Text Available The article seeks to study general aspects of the main coronaviruses affecting pigs, their presentation in Colombia, and particular aspects of porcine epidemic diarrhea virus (PEDV, emerging in different countries and generating a great impact on the health and economy of the swine industry. The main coronaviruses affecting swine are porcine transmissible gastroenteritis virus (TGEV, porcine respiratory coronavirus (PRCV, porcine hemagglutinating encephalomyelitis virus (PHEV, PEDV, and porcine deltacoronavirus (PDCoV. Long ago in Colombia there had been reports of TGEV and PRCV associated with the importation of animals from the United States, which was controlled in the infected farms and in quarantine units. PEDV was first detected in Colombia in mid-March 2014; the Colombian Agricultural Institute issued a health alert in Neiva (Huila, Fusagasugá and Silvania (Cundinamarca, and Puerto López (Meta due to the unusual presentation of epidemic vomiting and diarrhea in young and adult animals, abortion in pregnant sows, with high mortality rates (up to 100% in animals during the first week of age. At present the disease has been reported in other municipalities of the country as well as in different countries with similar clinical conditions and mortality rates in pigs with high economic losses for the swine sector.

  16. Significance of hepatitis virus infection in the oncogenic initiation of hepatocellular carcinoma.

    Science.gov (United States)

    Sukowati, Caecilia H C; El-Khobar, Korri E; Ie, Susan I; Anfuso, Beatrice; Muljono, David H; Tiribelli, Claudio

    2016-01-28

    Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related death worldwide. Chronic infection of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) is a major risk factor in the development of the HCC, independently from excessive alcohol abuse and metabolic disease. Since the biology of HBV and HCV is different, their oncogenic effect may go through different mechanisms, direct and/or indirect. Viral hepatitis infection is associated with cellular inflammation, oxidative stress, and DNA damage, that may lead to subsequent hepatic injuries such as chronic hepatitis, fibrosis, cirrhosis, and finally HCC. Direct oncogenic properties of these viruses are related with their genotypic characteristics and the ability of viral proteins to interact with host proteins, thus altering the molecular pathways balance of the cells. In addition, the integration of HBV DNA, especially the gene S and X, in a particular site of the host genome can disrupt chromosomal stability and may activate various oncogenic mechanisms, including those in hematopoietic cells. Recently, several studies also had demonstrated that viral hepatitis could trigger the population of hepatic cancer stem cells. This review summarize available pre-clinical and clinical data in literature regarding oncogenic properties of HBV and HCV in the early initiation of HCC.

  17. Clinical significance of spasmolytic polypeptide-expressing metaplasia and intestinal metaplasia in Epstein-Barr virus-associated and Epstein-Barr virus-negative gastric cancer.

    Science.gov (United States)

    Zhang, Yu; Chen, Jian-Ning; Dong, Min; Zhang, Zhi-Gang; Zhang, Yi-Wang; Wu, Jun-Yan; Du, Hong; Li, Hai-Gang; Huang, Yan; Shao, Chun-Kui

    2017-05-01

    Spasmolytic polypeptide-expressing metaplasia (SPEM) and intestinal metaplasia (IM) have been recognized as neoplastic precursors in gastric carcinogenesis. We explored the relationship between SPEM and IM in Epstein-Barr virus-associated (EBVaGC) and Epstein-Barr virus-negative (EBVnGC) gastric cancer. Sixty-four EBVaGC and one hundred and fifty-four EBVnGC patients were included. EBV positivity was identified using Epstein-Barr virus-encoded RNA-1 in situ hybridization. SPEM was subclassified into absent, early, and advanced SPEM. Acute and chronic inflammation was graded as absent, mild, moderate, and marked. Univariate and multivariate logistic regression analyses were conducted to analyze the correlation between SPEM, IM, and inflammation. Our study revealed that SPEM was detected in 87.5% EBVaGC and 85.1% EBVnGC patients. Distribution of patients according to the SPEM classification was significantly different between EBVaGC and EBVnGC groups (P=.038). IM was observed less frequently in EBVaGC when compared with EBVnGC patients (P<.001). No difference was observed between EBVaGC and EBVnGC in the levels of acute and chronic inflammation. A positive correlation between IM and SPEM status was observed in both EBVaGC and EBVnGC patients. Furthermore, advanced SPEM was an independent influential factor to IM in EBVnGC (P=.013). In conclusion, SPEM was associated with both EBVaGC and EBVnGC more frequently than IM. Moreover, advanced SPEM had a stronger association with IM than early SPEM in EBVnGC. These results suggest that identification of SPEM should be used as a high-risk indicator for detecting early gastric carcinoma, and should be brought to the attention of pathologists and clinicians. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Localization of an evolutionarily conserved protein proton pyrophosphatase in evolutionarily distant plants oryza sativa and physcomitrella patens

    Science.gov (United States)

    Proton Pyrophosphatase (H+-PPase) is a highly evolutionarily conserved protein that is prevalent in the plant kingdom. One of the salient features of H+-PPase expression pattern, at least in vascular plants like Arabidopsis, is its conspicuous localization in both actively dividing cells and the phl...

  19. Significance of Epstein-Barr virus (HHV-4 and CMV (HHV-5 infection among subtype-C human immunodeficiency virus-infected individuals

    Directory of Open Access Journals (Sweden)

    J Sachithanandham

    2014-01-01

    Full Text Available Purpose: Opportunistic viral infections are one of the major causes of morbidity and mortality in HIV infection and their molecular detection in the whole blood could be a useful diagnostic tool. Objective: The frequency of opportunistic DNA virus infections among HIV-1-infected individuals using multiplex real-time PCR assays was studied. Materials and Methods: The subjects were in two groups; group 1: Having CD4 counts 350 cells/µl (n = 173. Individuals were classified by WHO clinical staging system. Samples from 70 healthy individuals were tested as controls. In-house qualitative multiplex real-time PCR was standardised and whole blood samples from 291 were tested, followed by quantitative real-time PCR for positives. In a proportion of samples genotypes of Epstein-Barr virus (EBV and CMV were determined. Results: The two major viral infections observed were EBV and CMV. The univariate analysis of CMV load showed significant association with cryptococcal meningitis, oral hairy leukoplakia (OHL, CMV retinitis, CD4 counts and WHO staging (P < 0.05 while the multivariate analysis showed an association with OHL (P = 0.02 and WHO staging (P = 0.05. Univariate analysis showed an association of EBV load with CD4 counts and WHO staging (P < 0.05 and multivariate analysis had association only with CD4 counts. The CMV load was significantly associated with elevated SGPT and SGOT level (P < 0.05 while the EBV had only with SGOT. Conclusion: This study showed an association of EBV and CMV load with CD4+ T cell counts, WHO staging and elevated liver enzymes. These viral infections can accelerate HIV disease and multiplex real-time PCR can be used for the early detection. Genotype 1 and 2 of EBV and genotype gB1 and gB2 of CMV were the prevalent in the HIV-1 subtype C-infected south Indians.

  20. Clinical features of viral meningitis in adults: significant differences in cerebrospinal fluid findings among herpes simplex virus, varicella zoster virus, and enterovirus infections.

    Science.gov (United States)

    Ihekwaba, Ugo K; Kudesia, Goura; McKendrick, Michael W

    2008-09-15

    In this retrospective study, our objective was to review the epidemiology of viral meningitis and to compare clinical features associated with enterovirus, herpes simplex virus (HSV), and varicella zoster virus (VZV) infections in immunocompetent adults. Data on cerebrospinal fluid (CSF) samples submitted to the Trust Virology Laboratory (Sheffield, UK) from April 2004 through April 2007 were reviewed. Notes on immunocompetent adults who were polymerase chain reaction (PCR) positive for enterovirus, HSV type 2, or VZV and who had presented to local clinical departments were scrutinized (4 patients were positive for HSV type 1 and did not meet the inclusion criteria). A total of 2045 samples were analyzed for viral pathogens during the 3-year period. Of the 109 PCR-positive samples, 38 (35%) were from immunocompetent adults, of whom 22 were infected with enterovirus, 8 were infected with HSV type 2, and 8 were infected with VZV. The median ages were 32 years (range, 16-39 years), 39 years (range, 22-53 years), and 47.5 years (range, 26-80 years), respectively. Rash occurred after the meningitis symptoms in 5 patients infected with VZV (median time from meningitis symptoms to rash, 6 days). Protein levels were significantly higher in CSF samples from patients infected with HSV type 2 (median, 1205 mg/L) and in samples from those infected with VZV (median, 974 mg/L) than in samples from those infected with enterovirus (median, 640 mg/L; P = .001 and P = .01, respectively). White blood cell counts were significantly higher in CSF samples from patients infected with HSV type 2 (median, 240 x 10(6) cells/L) than in samples from those infected with enterovirus (median, 51 x 10(6) cells/L; P = .01). Enterovirus infection was the most common cause of viral meningitis in immunocompetent adults in this study. White blood cell counts and protein levels were significantly higher in CSF samples from patients infected with HSV type 2 than in samples from patients with enterovirus

  1. [The study on significance of detecting the hepatitis B virus large proteins in public health physical examination].

    Science.gov (United States)

    Pan, Guo-Shao; Jiang, Xing-Xiang; Chen, Jin-Kun; Cao, Dong-Qing; Zhao, Dan-Yan; Jian, Ming-Zhi; Zhang, Yi

    2011-06-01

    It was to explore the application of the hepatitis B virus large proteins (HBV-LP) in public health physical examination through clinical testing of HBV-LP in Catering practitioners, students and soldiers of New requisition etc. 709 samples of HBV infection people were collected in public health physical examination and all collected samples were detected. ELISA was used to detect HBV serum markers (HBV-M) and HBV-LP. Real-time PCR was applied to detect quantity of HBV DNA. (1) The detectable results of HBV-LP and HBV DNA were no statistical significance in 709 samples. (2) The detectable results of HBV-LP and HBV DNA were also no statistical significance in different models of HBV infection patients. The values of chi2 and P were respectively 2.67, 0.60, 0.00 and 0.10, 0.44, 1.00. S/A of HBV-LP and the copies of HBV-DNA had a positive relationship (r = 0.959, P health physical examination. HBV-LP may be worth using widely in physical examination.

  2. Emergence of carp edema virus (CEV) and its significance to European common carp and koi Cyprinus carpio

    NARCIS (Netherlands)

    Way, K.; Haenen, O.; Stone, D.; Adamek, M.; Bergmann, S.M.; Bigarré, L.; Diserens, Nicolas; El-Matbouli, M.; Gjessing, M.C.; Jung-Schroers, V.; Leguay, E.; Matras, M.; Olesen, Niels J.; Panzarin, Valentina; Piačková, V.; Toffan, A.; Vendramin, N.; Veselý, T.; Waltzek, T.

    2017-01-01

    Carp edema virus disease (CEVD), also known as koi sleepy disease, is caused by a poxvirus associated with outbreaks of clinical disease in koi and common carp Cyprinus carpio. Originally characterised in Japan in the 1970s, international trade in koi has led to the spread of CEV, although the first

  3. Harvey murine sarcoma virus p21 ras protein: biological and biochemical significance of the cysteine nearest the carboxy terminus

    DEFF Research Database (Denmark)

    Willumsen, B M; Norris, K; Papageorge, A G

    1984-01-01

    Previous studies of premature chain termination mutants and in frame deletion mutants of the p21 ras transforming protein encoded by the transforming gene of Harvey murine sarcoma virus (Ha-MuSV) have suggested that the C terminus is required for cellular transformation, lipid binding, and membrane...

  4. Emergence of carp edema virus (CEV) and its significance to European common carp and koi Cyprinus carpio

    DEFF Research Database (Denmark)

    Way, K.; Haenen, O.; Stone, D.

    2017-01-01

    Carp edema virus disease (CEVD), also known as koi sleepy disease, is caused by a poxvirus associated with outbreaks of clinical disease in koi and common carp Cyprinus carpio. Originally characterised in Japan in the 1970s, international trade in koi has led to the spread of CEV, although...

  5. 76 FR 50447 - Endangered and Threatened Species; 5-Year Reviews for 5 Evolutionarily Significant Units of...

    Science.gov (United States)

    2011-08-15

    ...: Background Under the ESA, a list of endangered and threatened wildlife and plant species must be maintained. The list is published at 50 CFR 17.11 (for animals) and 17.12 (for plants). Section 4(c)(2)(A) of the... considered new genetic and biogeographic information related to each species' freshwater and estuarine...

  6. 76 FR 50448 - Endangered and Threatened Species; 5-Year Reviews for 17 Evolutionarily Significant Units and...

    Science.gov (United States)

    2011-08-15

    ...; (2) Snake River spring/ summer-run Chinook salmon; (3) Puget Sound Chinook salmon; (4) Lower Columbia River Chinook salmon; (5) Upper Willamette Chinook salmon; (6) Snake River fall-run Chinook salmon; (7...; (10) Snake River sockeye salmon; and (11) Ozette Lake sockeye salmon. We did not complete a 5-year...

  7. Tumor-selective replication herpes simplex virus-based technology significantly improves clinical detection and prognostication of viable circulating tumor cells

    DEFF Research Database (Denmark)

    Zhang, Wen; Bao, Li; Yang, Shaoxing

    2016-01-01

    Detection of circulating tumor cells remains a significant challenge due to their vast physical and biological heterogeneity. We developed a cell-surface-marker-independent technology based on telomerase-specific, replication-selective oncolytic herpes-simplex-virus-1 that targets telomerase...

  8. A mouse model to study immunity against pseudorabies virus infection: Significance of CD4+ and CD8+ cells in protective immunity

    NARCIS (Netherlands)

    Bianchi, A.T.J.; Moonen-Leusen, H.W.M.; Milligen, van F.J.; Savelkoul, H.F.J.; Zwart, R.J.; Kimman, T.G.

    1998-01-01

    In this study we firstly established a vaccination/challenge model to study pseudorabies virus infection in mice. The mouse model was used to investigate the significance of CD4 and CD8 cells and of IFN production in protective immunity. Functional depletion of CD4 and CD8 and IFN was obtained in

  9. Measuring the Evolutionarily Important Goals of Situations: Situational Affordances for Adaptive Problems

    National Research Council Canada - National Science Library

    Brown, Nicolas A; Neel, Rebecca; Sherman, Ryne A

    2015-01-01

    .... This article introduces the Situational Affordances for Adaptive Problems (SAAP), a measure of situation characteristics that promotes or prevents the achievement of these evolutionarily important goals...

  10. Evolutionarily advanced ant farmers rear polyploid fungal crops

    DEFF Research Database (Denmark)

    Kooij, Pepijn Wilhelmus; Aanen, D.K.; Schiøtt, Morten

    2015-01-01

    Innovative evolutionary developments are often related to gene or genome duplications. The crop fungi of attine fungus-growing ants are suspected to have enhanced genetic variation reminiscent of polyploidy, but this has never been quantified with cytological data and genetic markers. We estimated...... the number of nuclei per fungal cell for 42 symbionts reared by 14 species of Panamanian fungus-growing ants. This showed that domesticated symbionts of higher attine ants are polykaryotic with 7-17 nuclei per cell, whereas nonspecialized crops of lower attines are dikaryotic similar to most free...... of the basal higher attine genera Trachymyrmex and Sericomyrmex was only slightly enhanced, but the evolutionarily derived crop fungi of Atta and Acromyrmex leaf-cutting ants had much higher genetic variation. Our opposite ploidy models indicated that the symbionts of Trachymyrmex and Sericomyrmex are likely...

  11. VIRUSES

    Indian Academy of Sciences (India)

    and-mouth disease in livestock was an infectious particle smaller than any bacteria. This was the first clue to the nature of viruses, genetic entities that lie somewhere in the gray area between living and non-living states.

  12. A significant productive in vivo infection of resting cells with simian immunodeficiency virus in a macaque with AIDS.

    Science.gov (United States)

    Pahar, Bapi; Lala, Wendy; Kuebler, Dot; Liu, David

    2017-04-01

    Identifying the cells that can be infected with HIV in vivo and thus potentially persist as latent reservoirs is of high priority. Here, we report the major infected cells in a chronically simian immunodeficiency virus (SIV)-infected macaque that developed AIDS and encephalitis. A majority of the infected cells were detected as non-proliferating resting cells. SIV-infected non-proliferating resting cells were found to be playing an important role in viral pathogenesis, persistence, or reservoir formation. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Prevalence of gastrointestinal symptoms in patients with influenza, clinical significance, and pathophysiology of human influenza viruses in faecal samples: what do we know?

    Science.gov (United States)

    Minodier, Laetitia; Charrel, Remi N; Ceccaldi, Pierre-Emmanuel; van der Werf, Sylvie; Blanchon, Thierry; Hanslik, Thomas; Falchi, Alessandra

    2015-12-12

    This review provides for the first time an assessment of the current understanding about the occurrence and the clinical significance of gastrointestinal (GI) symptoms in influenza patients, and their correlation with the presence of human influenza viruses in stools of patients with confirmed influenza virus infection. Studies exploring how human influenza viruses spread to the patient's GI tract after a primary respiratory infection have been summarized. We conducted a systematic search of published peer-reviewed literature up to June 2015 with regard to the above-mentioned aspects, focusing on human influenza viruses (A(H1N1), A(H1N1)pdm09, A(H3N2), and B). Forty-four studies were included in this systematic review and meta-analysis. The pooled prevalence of any digestive symptoms ranged from 30.9% (95% CI, 9.8 to 57.5; I(2) = 97.5%) for A(H1N1)pdm09 to 2.8% (95% CI, 0.6 to 6.5; I(2) = 75.4%) for A(H1N1). The pooled prevalence of influenza viruses in stool was 20.6% (95% CI, 8.9 to 35.5; I(2) = 96.8%), but their correlation with GI symptoms has rarely been explored. The presence of viral RNA in stools because of haematogenous dissemination to organs via infected lymphocytes is likely, but the potential to cause direct intestinal infection and faecal-oral transmission warrants further investigation. This review highlights the gaps in our knowledge, and the high degree of uncertainty about the prevalence and significance of GI symptoms in patients with influenza and their correlation with viral RNA positivity in stool because of the high level of heterogeneity among studies.

  14. Evolutionarily conserved TRH neuropeptide pathway regulates growth in Caenorhabditis elegans.

    Science.gov (United States)

    Van Sinay, Elien; Mirabeau, Olivier; Depuydt, Geert; Van Hiel, Matthias Boris; Peymen, Katleen; Watteyne, Jan; Zels, Sven; Schoofs, Liliane; Beets, Isabel

    2017-05-16

    In vertebrates thyrotropin-releasing hormone (TRH) is a highly conserved neuropeptide that exerts the hormonal control of thyroid-stimulating hormone (TSH) levels as well as neuromodulatory functions. However, a functional equivalent in protostomian animals remains unknown, although TRH receptors are conserved in proto- and deuterostomians. Here we identify a TRH-like neuropeptide precursor in Caenorhabditis elegans that belongs to a bilaterian family of TRH precursors. Using CRISPR/Cas9 and RNAi reverse genetics, we show that TRH-like neuropeptides, through the activation of their receptor TRHR-1, promote growth in Celegans TRH-like peptides from pharyngeal motor neurons are required for normal body size, and knockdown of their receptor in pharyngeal muscle cells reduces growth. Mutants deficient for TRH signaling have no defects in pharyngeal pumping or isthmus peristalsis rates, but their growth defect depends on the bacterial diet. In addition to the decrease in growth, trh-1 mutants have a reduced number of offspring. Our study suggests that TRH is an evolutionarily ancient neuropeptide, having its origin before the divergence of protostomes and deuterostomes, and may ancestrally have been involved in the control of postembryonic growth and reproduction.

  15. The effect of foot-and-mouth disease (FMD) vaccination on virus transmission and the significance for the field.

    Science.gov (United States)

    Orsel, Karin; Bouma, Annemarie

    2009-10-01

    Vaccination against foot-and-mouth disease (FMD) might be one of the control measures used during an FMD epidemic depending on the local epidemiological situation, the status of the country, and the opinion of policy makers. A sound decision on vaccination can be made only if there is sufficient scientific knowledge on the effectiveness of vaccination in eliminating the virus from the population. An important question is whether a single vaccination applied as an emergency vaccine can contribute to the control of an epidemic. This paper presents the results of transmission experiments on vaccine efficacy in groups of cattle, pigs, and sheep and concludes that vaccination seemed to be effective in cattle and sheep, but was less effective in pigs. The possible implications for application to field conditions are discussed.

  16. Mutagenic study of codons 74 and 215 of the human immunodeficiency virus type 1 reverse transcriptase, which are significant in nucleoside analog resistance.

    Science.gov (United States)

    Lacey, S F; Larder, B A

    1994-05-01

    Mutation in the human immunodeficiency virus type 1 reverse transcriptase (RT) at codon 215 has been shown to play a significant role in resistance to zidovudine (AZT). Substitution of threonine with tyrosine or phenylalanine alone confers decreased susceptibility to the inhibitor. In this study we constructed a panel of 10 viruses with different amino acids at this codon, including 7 novel mutants, and assessed their susceptibilities to AZT. The majority of the new mutants were AZT sensitive, whereas the Thr-215-->Trp mutant was partially resistant (threefold less susceptible). A combination of the Thr-215-->Trp with the other AZT resistance mutations Lys-70-->Arg and Met-41-->Leu gave additive resistance. The Thr-215-->Phe virus was less AZT resistant than the Thr-215-->Tyr mutant, both on its own and when each was combined with the Met-41-->Leu mutant. These observations confirm the general hypothesis that increased bulk of the amino acid side chains at this position confers decreased AZT sensitivity. A leucine-to-valine substitution at codon 74 has previously been found to confer dideoxynucleoside resistance. We constructed mutants with five novel amino acid substitutions (Ala, Gly, Glu, Met, and Asp) at codon 74. Of these, only one (that with the Met substitution) retained enough RT activity to yield viable virus. It thus appears that there are severe structure-function constraints on the amino acid side chains at this position in the enzyme. The activities of the Leu-74-->Ala and Leu-74-->Met RT enzymes expressed in Escherichia coli appeared to have reduced susceptibility to ddGTP compared with the wild-type enzyme. The mutants described in this work may prove useful for correlation with structural studies of the human immunodeficiency virus type 1 RT.

  17. Emergence of carp edema virus (CEV) and its significance to European common carp and koi Cyprinus carpio.

    Science.gov (United States)

    Way, K; Haenen, O; Stone, D; Adamek, M; Bergmann, S M; Bigarré, L; Diserens, N; El-Matbouli, M; Gjessing, M C; Jung-Schroers, V; Leguay, E; Matras, M; Olesen, N J; Panzarin, V; Piačková, V; Toffan, A; Vendramin, N; Vesel, T; Waltzek, T

    2017-10-18

    Carp edema virus disease (CEVD), also known as koi sleepy disease, is caused by a poxvirus associated with outbreaks of clinical disease in koi and common carp Cyprinus carpio. Originally characterised in Japan in the 1970s, international trade in koi has led to the spread of CEV, although the first recognised outbreak of the disease outside of Japan was not reported until 1996 in the USA. In Europe, the disease was first recognised in 2009 and, as detection and diagnosis have improved, more EU member states have reported CEV associated with disease outbreaks. Although the structure of the CEV genome is not yet elucidated, molecular epidemiology studies have suggested distinct geographical populations of CEV infecting both koi and common carp. Detection and identification of cases of CEVD in common carp were unreliable using the original PCR primers. New primers for conventional and quantitative PCR (qPCR) have been designed that improve detection, and their sequences are provided in this paper. The qPCR primers have successfully detected CEV DNA in archive material from investigations of unexplained carp mortalities conducted >15 yr ago. Improvement in disease management and control is possible, and the principles of biosecurity, good health management and disease surveillance, applied to koi herpesvirus disease, can be equally applied to CEVD. However, further research studies are needed to fill the knowledge gaps in the disease pathogenesis and epidemiology that, currently, prevent an accurate assessment of the likely impact of CEVD on European koi and common carp aquaculture and on wild carp stocks.

  18. Aligning science and policy to achieve evolutionarily enlightened conservation.

    Science.gov (United States)

    Cook, Carly N; Sgrò, Carla M

    2017-06-01

    There is increasing recognition among conservation scientists that long-term conservation outcomes could be improved through better integration of evolutionary theory into management practices. Despite concerns that the importance of key concepts emerging from evolutionary theory (i.e., evolutionary principles and processes) are not being recognized by managers, there has been little effort to determine the level of integration of evolutionary theory into conservation policy and practice. We assessed conservation policy at 3 scales (international, national, and provincial) on 3 continents to quantify the degree to which key evolutionary concepts, such as genetic diversity and gene flow, are being incorporated into conservation practice. We also evaluated the availability of clear guidance within the applied evolutionary biology literature as to how managers can change their management practices to achieve better conservation outcomes. Despite widespread recognition of the importance of maintaining genetic diversity, conservation policies provide little guidance about how this can be achieved in practice and other relevant evolutionary concepts, such as inbreeding depression, are mentioned rarely. In some cases the poor integration of evolutionary concepts into management reflects a lack of decision-support tools in the literature. Where these tools are available, such as risk-assessment frameworks, they are not being adopted by conservation policy makers, suggesting that the availability of a strong evidence base is not the only barrier to evolutionarily enlightened management. We believe there is a clear need for more engagement by evolutionary biologists with policy makers to develop practical guidelines that will help managers make changes to conservation practice. There is also an urgent need for more research to better understand the barriers to and opportunities for incorporating evolutionary theory into conservation practice. © 2016 Society for Conservation

  19. Fusion of protegrin-1 and plectasin to MAP30 shows significant inhibition activity against dengue virus replication.

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    Hussin A Rothan

    Full Text Available Dengue virus (DENV broadly disseminates in tropical and sub-tropical countries and there are no vaccine or anti-dengue drugs available. DENV outbreaks cause serious economic burden due to infection complications that requires special medical care and hospitalization. This study presents a new strategy for inexpensive production of anti-DENV peptide-fusion protein to prevent and/or treat DENV infection. Antiviral cationic peptides protegrin-1 (PG1 and plectasin (PLSN were fused with MAP30 protein to produce recombinant antiviral peptide-fusion protein (PG1-MAP30-PLSN as inclusion bodies in E. coli. High yield production of PG1-MAP30-PLSN protein was achieved by solubilization of inclusion bodies in alkaline buffer followed by the application of appropriate refolding techniques. Antiviral PG1-MAP30-PLSN protein considerably inhibited DENV protease (NS2B-NS3pro with half-maximal inhibitory concentration (IC50 0.5±0.1 μM. The real-time proliferation assay (RTCA and the end-point proliferation assay (MTT assay showed that the maximal-nontoxic dose of the peptide-fusion protein against Vero cells is approximately 0.67±0.2 μM. The cell-based assays showed considerable inhibition of the peptide-fusion protein against binding and proliferating stages of DENV2 into the target cells. The peptide-fusion protein protected DENV2-challeged mice with 100% of survival at the dose of 50 mg/kg. In conclusion, producing recombinant antiviral peptide-fusion protein by combining short antiviral peptide with a central protein owning similar activity could be useful to minimize the overall cost of short peptide production and take advantage of its synergistic antiviral activities.

  20. Infection and pathogenesis of canine, equine, and human influenza viruses in canine tracheas.

    Science.gov (United States)

    Gonzalez, Gaelle; Marshall, John F; Morrell, Joanna; Robb, David; McCauley, John W; Perez, Daniel R; Parrish, Colin R; Murcia, Pablo R

    2014-08-01

    Influenza A viruses (IAVs) can jump species barriers and occasionally cause epidemics, epizootics, pandemics, and panzootics. Characterizing the infection dynamics at the target tissues of natural hosts is central to understanding the mechanisms that control host range, tropism, and virulence. Canine influenza virus (CIV; H3N8) originated after the transfer of an equine influenza virus (EIV) into dogs. Thus, comparing CIV and EIV isolates provides an opportunity to study the determinants of influenza virus emergence. Here we characterize the replication of canine, equine, and human IAVs in the trachea of the dog, a species to which humans are heavily exposed. We define a phenotype of infection for CIV, which is characterized by high levels of virus replication and extensive tissue damage. CIV was compared to evolutionarily distinct EIVs, and the early EIV isolates showed an impaired ability to infect dog tracheas, while EIVs that circulated near the time of CIV emergence exhibited a CIV-like infection phenotype. Inoculating dog tracheas with various human IAVs (hIAVs) showed that they infected the tracheal epithelium with various efficiencies depending on the virus tested. Finally, we show that reassortant viruses carrying gene segments of CIV and hIAV are viable and that addition of the hemagglutinin (HA) and neuraminidase (NA) of CIV to the 2009 human pandemic virus results in a virus that replicates at high levels and causes significant lesions. This provides important insights into the role of evolution on viral emergence and on the role of HA and NA as determinants of pathogenicity. Influenza A viruses (IAVs) have entered new host species in recent history, sometimes with devastating consequences. Canine influenza virus (CIV) H3N8 originated from a direct transfer of an equine influenza virus (EIV) in the early 2000s. We studied the infection patterns of IAVs that circulate in dogs or to which dogs are commonly exposed and showed that CIV emergence was likely

  1. An evolutionarily conserved sexual signature in the primate brain.

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    Björn Reinius

    2008-06-01

    Full Text Available The question of a potential biological sexual signature in the human brain is a heavily disputed subject. In order to provide further insight into this issue, we used an evolutionary approach to identify genes with sex differences in brain expression level among primates. We reasoned that expression patterns important to uphold key male and female characteristics may be conserved during evolution. We selected cortex for our studies because this specific brain region is responsible for many higher behavioral functions. We compared gene expression profiles in the occipital cortex of male and female humans (Homo sapiens, a great ape and cynomolgus macaques (Macaca fascicularis, an old world monkey, two catarrhine species that show abundant morphological sexual dimorphism, as well as in common marmosets (Callithrix Jacchus, a new world monkey which are relatively sexually monomorphic. We identified hundreds of genes with sex-biased expression patterns in humans and macaques, while fewer than ten were differentially expressed between the sexes in marmosets. In primates, a general rule is that many of the morphological and behavioral sexual dimorphisms seen in polygamous species, such as macaques, are typically less pronounced in monogamous species such as the marmosets. Our observations suggest that this correlation may also be reflected in the extent of sex-biased gene expression in the brain. We identified 85 genes with common sex-biased expression, in both human and macaque and 2 genes, X inactivation-specific transcript (XIST and Heat shock factor binding protein 1 (HSBP1, that were consistently sex-biased in the female direction in human, macaque, and marmoset. These observations imply a conserved signature of sexual gene expression dimorphism in cortex of primates. Further, we found that the coding region of female-biased genes is more evolutionarily constrained compared to the coding region of both male-biased and non sex-biased brain

  2. Endomembrane Ca2+-AtPases play a significant role in virus-induced adaptation to oxidative stress

    DEFF Research Database (Denmark)

    Shabala, Sergey; Bækgaard, Lone; Shabala, Lana

    2011-01-01

    in adaptive responses to oxidative stress by removing excessive Ca2+ from the cytosol, and that their functional expression is significantly altered in PVX-inoculated plants. These findings highlight the crucial role of Ca2+ efflux systems in acquired tolerance to oxidative stress and open up prospects...... for practical applications in agriculture, after in-depth comprehension of the fundamental mechanisms involved in common responses to environmental factors at the genomic, cellular and organismal levels....

  3. Delayed Dosing of S-033188, a Novel Inhibitor of Influenza Virus Cap-dependent Endonuclease, Exhibited Significant Reduction of Viral Titer and Mortality in Mice Infected with Influenza A Virus

    Science.gov (United States)

    Fukao, Keita; Ando, Yoshinori; Noshi, Takeshi; Kawai, Makoto; Yoshida, Ryu; Shishido, Takao; Naito, Akira

    2017-01-01

    Abstract Background Both epidemic and pandemic influenza are major public health concerns, but current standard treatment limits its usage by 48 hours from onsets. Furthermore, no antiviral drug has been shown to definitively reduce serious complications, hospitalization, or mortality in a randomized clinical trial. S-033188 is an orally available small molecule inhibitor of cap-dependent endonuclease that is essential for transcription and replication of influenza A and B virus. In this study, we evaluated the efficacy of delayed dosing of S-033188, either as single agent or in combination with oseltamivir, in mice infected with lethal doses of influenza A virus. Methods BALB/c mice were intranasally inoculated with A/PR/8/34 strain at 8.0 × 102 tissue culture infectious dose 50 (TCID50)/mouse. Mice were orally treated with S-033188 (0.5, 1.5, 15 or 50 mg/kg), oseltamivir phosphate (10 or 50 mg/kg), S-033188 (0.5 or 1.5 mg/kg) in combination with oseltamivir phosphate (10 or 50 mg/kg), or vehicle BID for 5 days, beginning at 96 hours after virus infection. Survival and body weight were then monitored through a 28-day period after infection. In addition, viral titer in the lung was determined during the treatment. Mice were euthanized and regarded as dead if their body weights were lower than 70% of the initial body weights according to humane endpoints. Results S-033188 monotherapy (15 or 50 mg/kg, BID for 5 days) completely eliminated mortality in mice, whereas oseltamivir monotherapy (10 or 50 mg/kg, BID for 5 days) exhibited only 10% or 40% survival (Figure1), respectively. S-033188 monotherapy also significantly reduced viral titer and prevented body weight loss, consistent with the prolonged survival. Furthermore, S-033188 (0.5 or 1.5 mg/kg) in combination with oseltamivir phosphate (10 or 50 mg/kg) exhibited significant improvement of mortality as compared with each oseltamivir phosphate monotherapy. Conclusion Delayed dosing of S-033188 exhibited

  4. Ecological interactions are evolutionarily conserved across the entire tree of life.

    Science.gov (United States)

    Gómez, José M; Verdú, Miguel; Perfectti, Francisco

    2010-06-17

    Ecological interactions are crucial to understanding both the ecology and the evolution of organisms. Because the phenotypic traits regulating species interactions are largely a legacy of their ancestors, it is widely assumed that ecological interactions are phylogenetically conserved, with closely related species interacting with similar partners. However, the existing empirical evidence is inadequate to appropriately evaluate the hypothesis of phylogenetic conservatism in ecological interactions, because it is both ecologically and taxonomically biased. In fact, most studies on the evolution of ecological interactions have focused on specialized organisms, such as some parasites or insect herbivores, belonging to a limited subset of the overall tree of life. Here we study the evolution of host use in a large and diverse group of interactions comprising both specialist and generalist acellular, unicellular and multicellular organisms. We show that, as previously found for specialized interactions, generalized interactions can be evolutionarily conserved. Significant phylogenetic conservatism of interaction patterns was equally likely to occur in symbiotic and non-symbiotic interactions, as well as in mutualistic and antagonistic interactions. Host-use differentiation among species was higher in phylogenetically conserved clades, irrespective of their generalization degree and taxonomic position within the tree of life. Our findings strongly suggest a shared pattern in the organization of biological systems through evolutionary time, mediated by marked conservatism of ecological interactions among taxa.

  5. High prevalence and significance of hepatitis D virus infection among treatment-naïve HBsAg-positive patients in Northern Vietnam.

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    Bui Tien Sy

    Full Text Available BACKGROUND: Hepatitis D virus (HDV infection is considered to cause more severe hepatitis than hepatitis B virus (HBV monoinfection. With more than 9.5 million HBV-infected people, Vietnam will face an enormous health burden. The prevalence of HDV in Vietnamese HBsAg-positive patients is speculative. Therefore, we assessed the prevalence of HDV in Vietnamese patients, determined the HDV-genotype distribution and compared the findings with the clinical outcome. METHODS: 266 sera of well-characterized HBsAg-positive patients in Northern Vietnam were analysed for the presence of HDV using newly developed HDV-specific RT-PCRs. Sequencing and phylogenetic analysis were performed for HDV-genotyping. RESULTS: The HDV-genome prevalence observed in the Vietnamese HBsAg-positive patients was high with 15.4% while patients with acute hepatitis showed 43.3%. Phylogenetic analysis demonstrated a predominance of HDV-genotype 1 clustering in an Asian clade while HDV-genotype 2 could be also detected. The serum aminotransferase levels (AST, ALT as well as total and direct bilirubin were significantly elevated in HDV-positive individuals (p<0.05. HDV loads were mainly low (<300 to 4.108 HDV-copies/ml. Of note, higher HDV loads were mainly found in HBV-genotype mix samples in contrast to single HBV-infections. In HBV/HDV-coinfections, HBV loads were significantly higher in HBV-genotype C in comparison to HBV-genotype A samples (p<0.05. CONCLUSION: HDV prevalence is high in Vietnamese individuals, especially in patients with acute hepatitis B. HDV replication activity showed a HBV-genotype dependency and could be associated with elevated liver parameters. Besides serological assays molecular tests are recommended for diagnosis of HDV. Finally, the high prevalence of HBV and HDV prompts the urgent need for HBV-vaccination coverage.

  6. Prognostic significance of catalase expression and its regulatory effects on hepatitis B virus X protein (HBx) in HBV-related advanced hepatocellular carcinomas

    Science.gov (United States)

    Cho, Mi-Young; Cheong, Jae Youn; Lim, Wonchung; Jo, Sujin; Lee, Youngsoo; Wang, Hee-Jung; Han, Kyou-Hoon; Cho, Hyeseong

    2014-01-01

    Hepatitis B virus X protein (HBx) plays a role in liver cancer development. We previously showed that ROS increased HBx levels and here, we investigated the role of antioxidants in the regulation of HBx expression and their clinical relevance. We found that overexpression of catalase induced a significant loss in HBx levels. The cysteine null mutant of HBx (Cys−) showed a dramatic reduction in its protein stability. In clonogenic proliferation assays, Huh7-X cells produced a significant number of colonies whereas Huh7-Cys− cells failed to generate them. The Cys at position 69 of HBx was crucial to maintain its protein stability and transactivation function in response to ROS. Among 50 HBV-related hepatocellular carcinoma (HCC) specimens, 72% of HCCs showed lower catalase levels than those of surrounding non-tumor tissues. In advanced stage IV, catalase levels in non-tumor tissues were increased whereas those in tumors were further reduced. Accordingly, patients with a high T/N ratio for catalase showed significantly longer survival than those with a low T/N ratio. Together, catalase expression in HCC patients can be clinically useful for prediction of patient survival, and restoration of catalase expression in HCCs could be an important strategy for intervention in HBV-induced liver diseases. PMID:25361011

  7. Lack of a clinically significant drug-drug interaction in healthy volunteers between the hepatitis C virus protease inhibitor boceprevir and the HIV integrase inhibitor raltegravir

    NARCIS (Netherlands)

    Kanter, C.T. de; Blonk, M.I.; Colbers, A.P.; Schouwenberg, B.J.J.W.; Burger, D.M.

    2013-01-01

    BACKGROUND: Patients coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) are likely to use both HIV and HCV treatment. Drug-drug interactions have been demonstrated between boceprevir, an HCV protease inhibitor, and frequently prescribed antiretroviral drugs, such as

  8. Significantly elevated number of human infections with H7N9 virus in Jiangsu in eastern China, October 2016 to January 2017.

    Science.gov (United States)

    Huo, Xiang; Chen, Liling; Qi, Xian; Huang, Haodi; Dai, Qigang; Yu, Huiyan; Xia, Yu; Liu, Wendong; Xu, Ke; Ma, Wang; Zhang, Jun; Bao, Changjun

    2017-03-30

    Since first identified in 2013, the H7N9 virus has caused several waves of human infections in China, with a current wave including a number of patients with very severe disease. Jiangsu is one of the most impacted provinces, whereby as of 31 January 2017, the number of human infections (n = 109) in the ongoing fifth H7N9 wave has exceeded the sum of those in the four preceding ones. Ten of 13 cities in Jiangsu have been affected, and clustered infections as well as one co-infection with seasonal influenza have been observed. With a median age of 58 years and 74.3% (81/109) of patients being male, the characteristics of cases are similar to those in previous waves, however patients with H7N9 seem to have an accelerated disease progression. Preliminary case fatality remains above 30%. No significant viral mutations have been found in key functional loci. Environmental H7N9 detection rate and number of days with high risk ambient temperatures were both significantly elevated during the month of December 2016 when most human infections were reported. A number of municipal governments in Jiangsu have implemented live poultry market closures to impede viral transmission to humans. A detectable decline in human infections has been observed in these municipalities and the entire province since January 2017. This article is copyright of The Authors, 2017.

  9. Motavizumab, A Neutralizing Anti-Respiratory Syncytial Virus (Rsv Monoclonal Antibody Significantly Modifies The Local And Systemic Cytokine Responses Induced By Rsv In The Mouse Model

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    Jafri Hasan S

    2007-10-01

    Full Text Available Abstract Motavizumab (MEDI-524 is a monoclonal antibody with enhanced neutralizing activity against RSV. In mice, motavizumab suppressed RSV replication which resulted in significant reduction of clinical parameters of disease severity. We evaluated the effect of motavizumab on the local and systemic immune response induced by RSV in the mouse model. Balb/c mice were intranasally inoculated with 106.5 PFU RSV A2 or medium. Motavizumab was given once intraperitoneally (1.25 mg/mouse as prophylaxis, 24 h before virus inoculation. Bronchoalveolar lavage (BAL and serum samples were obtained at days 1, 5 (acute and 28 (long-term post inoculation and analyzed with a multiplex assay (Beadlyte Upstate, NY for simultaneous quantitation of 18 cytokines: IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-5, IL-6, KC (similar to human IL-8, IL-10, IL-12p40, IL-12p70, IL-13, IL-17, TNF-α, MCP-1, RANTES, IFN-γ and GM-CSF. Overall, cytokine concentrations were lower in serum than in BAL samples. By day 28, only KC was detected in BAL specimens at low concentrations in all groups. Administration of motavizumab significantly reduced (p

  10. Analysis of Monocytic and Granulocytic Myeloid-Derived Suppressor Cells Subsets in Patients with Hepatitis C Virus Infection and Their Clinical Significance

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    Gang Ning

    2015-01-01

    Full Text Available Myeloid-derived suppressor cells (MDSCs have been shown to inhibit T-cell responses in many diseases, but, in hepatitis C virus (HCV infected patients, MDSCs are still poorly studied. In this assay, we investigated the phenotype and frequency of two new populations of MDSCs denoted as monocytic and granulocytic MDSCs (M-MDSCs and G-MDSCs in HCV infected patients and analyzed their clinical significance in these patients respectively. We found that the frequency of CD14+HLA-DR-/low cells (M-MDSCs from HCV infected patients (mean ± SE, 3.134% ± 0.340% was significantly increased when compared to healthy controls (mean ± SE, 1.764% ± 0.461% (Z = −2.438, P = 0.015, while there was no statistical difference between the frequency of HLA-DR-/lowCD33+CD11b+CD15+ (G-MDSCs of HCV infected patients and healthy donors (0.201% ± 0.038% versus 0.096% ± 0.026%, P > 0.05, which suggested that HCV infection could cause the proliferation of M-MDSCs instead of G-MDSCs. Besides, we found that the frequency of M-MDSCs in HCV infected patients had certain relevance with age (r = 0.358, P = 0.003; patients older than 40 years old group (mean ± SE, 3.673% ± 0.456% had a significantly higher frequency of M-MDSCs than that of age less than 40 years old group (mean ± SE, 2.363% ± 0.482% (Z = −2.685, P = 0.007. The frequency of M-MDSCs, however, had no correlation with HCV RNA loads, aspartate aminotransferase (AST, alanine aminotransferase (ALT, and the level of liver inflammation degree.

  11. An evolutionarily conserved mutual interdependence between Aire and microRNAs in promiscuous gene expression.

    Science.gov (United States)

    Ucar, Olga; Tykocinski, Lars-Oliver; Dooley, James; Liston, Adrian; Kyewski, Bruno

    2013-07-01

    The establishment and maintenance of central tolerance depends to a large extent on the ability of medullary thymic epithelial cells to express a variety of tissue-restricted antigens, the so-called promiscuous gene expression (pGE). Autoimmune regulator (Aire) is to date the best characterised transcriptional regulator known to at least partially coordinate pGE. There is accruing evidence that the expression of Aire-dependent and -independent genes is modulated by higher order chromatin configuration, epigenetic modifications and post-transcriptional control. Given the involvement of microRNAs (miRNAs) as potent post-transcriptional modulators of gene expression, we investigated their role in the regulation of pGE in purified mouse and human thymic epithelial cells (TECs). Microarray profiling of TEC subpopulations revealed evolutionarily conserved cell type and differentiation-specific miRNA signatures with a subset of miRNAs being significantly upregulated during terminal medullary thymic epithelial cell differentiation. The differential regulation of this subset of miRNAs was correlated with Aire expression and some of these miRNAs were misexpressed in the Aire knockout thymus. In turn, the specific absence of miRNAs in TECs resulted in a progressive reduction of Aire expression and pGE, affecting both Aire-dependent and -independent genes. In contrast, the absence of miR-29a only affected the Aire-dependent gene pool. These findings reveal a mutual interdependence of miRNA and Aire. © 2013 The Authors. European Journal of Immunology published byWiley-VCH Verlag GmbH & Co. KGaA Weinheim.

  12. Positive selection drives rapid evolution of certain amino acid residues in an evolutionarily highly conserved interferon-inducible antiviral protein of fishes.

    Science.gov (United States)

    Padhi, Abinash

    2013-01-01

    Viperin, an evolutionarily highly conserved interferon-inducible multifunctional protein, has previously been reported to exhibit antiviral activity against a wide range of DNA and RNA viruses. Utilizing the complete nucleotide coding sequence data of fish viperin antiviral genes, and employing the maximum likelihood-based codon substitution models, the present study reports the pervasive role of positive selection in the evolution of viperin antiviral protein in fishes. The overall rate of nonsynonymous (dN) to synonymous (dS) substitutions (dN/dS) for the three functional domains of viperin (N-terminal, central domain and C-terminal) were 1.1, 0.12, and 0.24, respectively. Codon-by-codon substitution analyses have revealed that while most of the positively selected sites were located at the N-terminal amphipathic α-helix domain, few amino acid residues at the C-terminal domain were under positive selection. However, none of the sites in the central domain were under positive selection. These results indicate that, although viperin is evolutionarily highly conserved, the three functional domains experienced differential selection pressures. Taken together with the results of previous studies, the present study suggests that the persistent antagonistic nature of surrounding infectious viral pathogens might be the likely cause for such adaptive evolutionary changes of certain amino acids in fish viperin antiviral protein.

  13. Linkage disequilibrium of evolutionarily conserved regions in the human genome

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    Johnson Todd A

    2006-12-01

    Full Text Available Abstract Background The strong linkage disequilibrium (LD recently found in genic or exonic regions of the human genome demonstrated that LD can be increased by evolutionary mechanisms that select for functionally important loci. This suggests that LD might be stronger in regions conserved among species than in non-conserved regions, since regions exposed to natural selection tend to be conserved. To assess this hypothesis, we used genome-wide polymorphism data from the HapMap project and investigated LD within DNA sequences conserved between the human and mouse genomes. Results Unexpectedly, we observed that LD was significantly weaker in conserved regions than in non-conserved regions. To investigate why, we examined sequence features that may distort the relationship between LD and conserved regions. We found that interspersed repeats, and not other sequence features, were associated with the weak LD tendency in conserved regions. To appropriately understand the relationship between LD and conserved regions, we removed the effect of repetitive elements and found that the high degree of sequence conservation was strongly associated with strong LD in coding regions but not with that in non-coding regions. Conclusion Our work demonstrates that the degree of sequence conservation does not simply increase LD as predicted by the hypothesis. Rather, it implies that purifying selection changes the polymorphic patterns of coding sequences but has little influence on the patterns of functional units such as regulatory elements present in non-coding regions, since the former are generally restricted by the constraint of maintaining a functional protein product across multiple exons while the latter may exist more as individually isolated units.

  14. Significance of the balance between regulatory T (Treg and T helper 17 (Th17 cells during hepatitis B virus related liver fibrosis.

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    Jing Li

    Full Text Available BACKGROUND: Hepatitis B virus-related liver fibrosis (HBV-LF always progresses from inflammation to fibrosis. However, the relationship between these two pathological conditions is not fully understood. Here, it is postulated that the balance between regulatory T (Treg cells and T helper 17 (Th17 cells as an indicator of inflammation may predict fibrosis progression of HBV-LF. METHODOLOGY/PRINCIPAL FINDINGS: The frequencies and phenotypes of peripheral Treg and Th17 cells of seventy-seven HBeAg-positive chronic hepatitis B (CHB patients who underwent liver biopsies and thirty healthy controls were determined by flow cytometry. In the periphery of CHB patients, both Treg and Th17 frequencies were significantly increased and correlated, and a lower Treg/Th17 ratio always indicated more liver injury and fibrosis progression. To investigate exact effects of Treg and Th17 cells during HBV-LF, a series of in vitro experiments were performed using purified CD4(+, CD4(+CD25(+, or CD4(+CD25(- cells from the periphery, primary human hepatic stellate cells (HSCs isolated from healthy liver specimens, human recombinant interleukin (IL-17 cytokine, anti-IL-17 antibody and HBcAg. In response to HBcAg, CD4(+CD25(+ cells significantly inhibited cell proliferation and cytokine production (especially IL-17 and IL-22 by CD4(+CD25(- cells in cell-contact and dose-dependent manners. In addition, CD4(+ cells from CHB patients, compared to those from HC subjects, dramatically promoted proliferation and activation of human HSCs. Moreover, in a dramatically dose-dependent manner, CD4(+CD25(+ cells from CHB patients inhibited, whereas recombinant IL-17 response promoted the proliferation and activation of HSCs. Finally, in vivo evidence about effects of Treg/Th17 balance during liver fibrosis was obtained in concanavalin A-induced mouse fibrosis models via depletion of CD25(+ or IL-17(+ cells, and it's observed that CD25 depletion promoted, whereas IL-17 depletion

  15. Genetic and biological characterization of a Porcine Reproductive and Respiratory Syndrome Virus 2 (PRRSV-2)causing significant clinical disease in the field

    DEFF Research Database (Denmark)

    Kvisgaard, Lise Kirstine; Larsen, Lars Erik; Hjulsager, Charlotte Kristiane

    2017-01-01

    Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is the cause of severe reproductive and respiratory disease in swine worldwide. In Denmark, both PRRSV-1 and PRRSV-2 are circulating and approximately 35% of pig herds are seropositive for PRRSV. In November 2010, a pig herd...... in the Northern part of Denmark experienced an infection with PRRSV-2 with clinical signs that were much more severe than normally reported from current Danish PRRSV-2 affected herds. Due to the clinical observations of reproductive failure in sows and high mortality in piglets, it was speculated that a new, more....... Virus shedding, acute phase protein responses and serological responses were comparable to those seen after experimental challenge with a Danish PRRSV-2 reference strain isolated in 1997. Vaccination with a commercial modified live PRRSV-2 vaccine had a clear reducing effect on virus shedding, magnitude...

  16. All Microorganisms Must Die, But How Many Get Lysed By Viruses? - Approaches to Assessing the Significance of Nano-Sized Agents of Mortality Among Communities of Phytoplankton

    Science.gov (United States)

    Fobbe, D. J.; Simmons, L. J.; Berges, J. A.

    2016-02-01

    Work with laboratory cultures and phytoplankton blooms has shown the potential for viruses to be dominant causes of mortality, but viral effects on phytoplankton community dynamics are less clear and more difficult to assess. Reasons for this include that viral-host relationships are difficult to establish and ongoing 'arms-races' of biological defenses and adaptations over short time scales obscure what is happening. We approached the problem using a small, well-studied urban pond as a model system, and monitoring phytoplankton and viral dynamics weekly through two years using flow cytometry. Flow cytometry allowed us to distinguish and enumerate phytoplankton groups and with cell staining, estimate proportions of living and dead cells. We adapted published methods for counting viruses using flow cytometry, and validated them against epifluorescent techniques. Modifications included: pre-filtration of samples through GF/F filters, fixation with glutaraldehyde, addition of EDTA prior to staining with SYBR Green©, and use of ultra-pure water as a diluent to obtain optimum concentrations. Viral counts ranged from 106 per ml (under ice in winter) to over 109 per ml (as summer phytoplankton blooms peaked). Viral abundances exceeded phytoplankton by up to three orders of magnitude. We could distinguish five groups of viruses based on SYBR Greenfluorescence and side scatter, and these showed seasonal changes. While many of these viruses probably infected heterotrophic bacteria, in some periods increases in viruses correlated with decline of phytoplankton groups, when changes in environmental parameters (e.g. temperature, irradiance, nutrients) were not apparent. Best correlations were found within 6 µm and smaller size fractions of phytoplankton versus larger groups. To examine links between viral lysis and phytoplankton, experiments are currently being conducted concentrating viruses and incubating them with natural communities of phytoplankton to monitor infection

  17. 50 CFR 226.212 - Critical habitat for 13 Evolutionarily Significant Units (ESUs) of salmon and steelhead...

    Science.gov (United States)

    2010-10-01

    ....1537, -123.1267) upstream to endpoint(s) in: Dungeness River (47.9386, -123.0885); Gray Wolf River (47....6050, Long -121.6323) upstream to endpoint(s) in: Dog River (45.4655, -121.5656); East Fork Hood River...

  18. 50 CFR 226.211 - Critical habitat for Seven Evolutionarily Significant Units (ESUs) of Salmon (Oncorhynchus spp...

    Science.gov (United States)

    2010-10-01

    ....9493); Connick Creek (40.0911, -123.8187); Cox Creek (40.0288, -123.8542); Cummings Creek (39.8431....6216); China Creek (40.1035, -123.9493); Connick Creek (40.0912, -123.8154); Cox Creek (40.0310, -123... Flat Creek (40.1444, -124.1636); Blue Slide Creek (40.1562, -123.9283); Box Canyon Creek (40.1078, -123...

  19. The first human epitope map of the alphaviral E1 and E2 proteins reveals a new E2 epitope with significant virus neutralizing activity.

    Directory of Open Access Journals (Sweden)

    Ann R Hunt

    2010-07-01

    Full Text Available Venezuelan equine encephalitis virus (VEEV is responsible for VEE epidemics that occur in South and Central America and the U.S. The VEEV envelope contains two glycoproteins E1 (mediates cell membrane fusion and E2 (binds receptor and elicits virus neutralizing antibodies. Previously we constructed E1 and E2 epitope maps using murine monoclonal antibodies (mMAbs. Six E2 epitopes (E2(c,d,e,f,g,h bound VEEV-neutralizing antibody and mapped to amino acids (aa 182-207. Nothing is known about the human antibody repertoire to VEEV or epitopes that engage human virus-neutralizing antibodies. There is no specific treatment for VEE; however virus-neutralizing mMAbs are potent protective and therapeutic agents for mice challenged with VEEV by either peripheral or aerosol routes. Therefore, fully human MAbs (hMAbs with virus-neutralizing activity should be useful for prevention or clinical treatment of human VEE.We used phage-display to isolate VEEV-specific hFabs from human bone marrow donors. These hFabs were characterized by sequencing, specificity testing, VEEV subtype cross-reactivity using indirect ELISA, and in vitro virus neutralization capacity. One E2-specific neutralizing hFAb, F5n, was converted into IgG, and its binding site was identified using competitive ELISA with mMAbs and by preparing and sequencing antibody neutralization-escape variants.Using 11 VEEV-reactive hFabs we constructed the first human epitope map for the alphaviral surface proteins E1 and E2. We identified an important neutralization-associated epitope unique to the human immune response, E2 aa115-119. Using a 9 A resolution cryo-electron microscopy map of the Sindbis virus E2 protein, we showed the probable surface location of this human VEEV epitope.The VEEV-neutralizing capacity of the hMAb F5 nIgG is similar to that exhibited by the humanized mMAb Hy4 IgG. The Hy4 IgG has been shown to limit VEEV infection in mice both prophylactically and therapeutically. Administration

  20. On Nash Equilibrium and Evolutionarily Stable States That Are Not Characterised by the Folk Theorem.

    Directory of Open Access Journals (Sweden)

    Jiawei Li

    Full Text Available In evolutionary game theory, evolutionarily stable states are characterised by the folk theorem because exact solutions to the replicator equation are difficult to obtain. It is generally assumed that the folk theorem, which is the fundamental theory for non-cooperative games, defines all Nash equilibria in infinitely repeated games. Here, we prove that Nash equilibria that are not characterised by the folk theorem do exist. By adopting specific reactive strategies, a group of players can be better off by coordinating their actions in repeated games. We call it a type-k equilibrium when a group of k players coordinate their actions and they have no incentive to deviate from their strategies simultaneously. The existence and stability of the type-k equilibrium in general games is discussed. This study shows that the sets of Nash equilibria and evolutionarily stable states have greater cardinality than classic game theory has predicted in many repeated games.

  1. On Nash Equilibrium and Evolutionarily Stable States That Are Not Characterised by the Folk Theorem

    Science.gov (United States)

    Li, Jiawei; Kendall, Graham

    2015-01-01

    In evolutionary game theory, evolutionarily stable states are characterised by the folk theorem because exact solutions to the replicator equation are difficult to obtain. It is generally assumed that the folk theorem, which is the fundamental theory for non-cooperative games, defines all Nash equilibria in infinitely repeated games. Here, we prove that Nash equilibria that are not characterised by the folk theorem do exist. By adopting specific reactive strategies, a group of players can be better off by coordinating their actions in repeated games. We call it a type-k equilibrium when a group of k players coordinate their actions and they have no incentive to deviate from their strategies simultaneously. The existence and stability of the type-k equilibrium in general games is discussed. This study shows that the sets of Nash equilibria and evolutionarily stable states have greater cardinality than classic game theory has predicted in many repeated games. PMID:26288088

  2. Emerged HA and NA mutants of the pandemic influenza H1N1 viruses with increasing epidemiological significance in Taipei and Kaohsiung, Taiwan, 2009-10.

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    Chuan-Liang Kao

    Full Text Available The 2009 influenza pandemic provided an opportunity to observe dynamic changes of the hemagglutinin (HA and neuraminidase (NA of pH1N1 strains that spread in two metropolitan areas--Taipei and Kaohsiung. We observed cumulative increases of amino acid substitutions of both HA and NA that were higher in the post-peak than in the pre-peak period of the epidemic. About 14.94% and 3.44% of 174 isolates had one and two amino acids changes, respective, in the four antigenic sites. One unique adaptive mutation of HA2 (E374K was first detected three weeks before the epidemic peak. This mutation evolved through the epidemic, and finally emerged as the major circulated strain, with significantly higher frequency in the post-peak period than in the pre-peak (64.65% vs 9.28%, p<0.0001. E374K persisted until ten months post-nationwide vaccination without further antigenic changes (e.g. prior to the highest selective pressure. In public health measures, the epidemic peaked at seven weeks after oseltamivir treatment was initiated. The emerging E374K mutants spread before the first peak of school class suspension, extended their survival in high-density population areas before vaccination, dominated in the second wave of class suspension, and were fixed as herd immunity developed. The tempo-spatial spreading of E374K mutants was more concentrated during the post-peak (p = 0.000004 in seven districts with higher spatial clusters (p<0.001. This is the first study examining viral changes during the naïve phase of a pandemic of influenza through integrated virological/serological/clinical surveillance, tempo-spatial analysis, and intervention policies. The vaccination increased the percentage of E374K mutants (22.86% vs 72.34%, p<0.001 and significantly elevated the frequency of mutations in Sa antigenic site (2.36% vs 23.40%, p<0.001. Future pre-vaccination public health efforts should monitor amino acids of HA and NA of pandemic influenza viruses isolated at

  3. Protection of CpG islands from DNA methylation is DNA-encoded and evolutionarily conserved.

    Science.gov (United States)

    Long, Hannah K; King, Hamish W; Patient, Roger K; Odom, Duncan T; Klose, Robert J

    2016-08-19

    DNA methylation is a repressive epigenetic modification that covers vertebrate genomes. Regions known as CpG islands (CGIs), which are refractory to DNA methylation, are often associated with gene promoters and play central roles in gene regulation. Yet how CGIs in their normal genomic context evade the DNA methylation machinery and whether these mechanisms are evolutionarily conserved remains enigmatic. To address these fundamental questions we exploited a transchromosomic animal model and genomic approaches to understand how the hypomethylated state is formed in vivo and to discover whether mechanisms governing CGI formation are evolutionarily conserved. Strikingly, insertion of a human chromosome into mouse revealed that promoter-associated CGIs are refractory to DNA methylation regardless of host species, demonstrating that DNA sequence plays a central role in specifying the hypomethylated state through evolutionarily conserved mechanisms. In contrast, elements distal to gene promoters exhibited more variable methylation between host species, uncovering a widespread dependence on nucleotide frequency and occupancy of DNA-binding transcription factors in shaping the DNA methylation landscape away from gene promoters. This was exemplified by young CpG rich lineage-restricted repeat sequences that evaded DNA methylation in the absence of co-evolved mechanisms targeting methylation to these sequences, and species specific DNA binding events that protected against DNA methylation in CpG poor regions. Finally, transplantation of mouse chromosomal fragments into the evolutionarily distant zebrafish uncovered the existence of a mechanistically conserved and DNA-encoded logic which shapes CGI formation across vertebrate species. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  4. Earthworms and Humans in Vitro: Characterizing Evolutionarily Conserved Stress and Immune Responses to Silver Nanoparticles

    DEFF Research Database (Denmark)

    Hayashi, Yuya; Engelmann, Péter; Foldbjerg, Rasmus

    2012-01-01

    on the conserved biological processes, and provide the first in vitro analysis of molecular and cellular toxicity mechanisms in the earthworm Eisenia fetida exposed to AgNPs (83 ± 22 nm). While we observed a clear difference in cytotoxicity of dissolved silver salt on earthworm coelomocytes and human cells (THP-1...... in the coelomocytes and THP-1 cells. Our findings provide mechanistic clues on cellular innate immunity toward AgNPs that is likely to be evolutionarily conserved across the animal kingdom....

  5. Evolutionarily stable learning schedules and cumulative culture in discrete generation models.

    Science.gov (United States)

    Aoki, Kenichi; Wakano, Joe Yuichiro; Lehmann, Laurent

    2012-06-01

    Individual learning (e.g., trial-and-error) and social learning (e.g., imitation) are alternative ways of acquiring and expressing the appropriate phenotype in an environment. The optimal choice between using individual learning and/or social learning may be dictated by the life-stage or age of an organism. Of special interest is a learning schedule in which social learning precedes individual learning, because such a schedule is apparently a necessary condition for cumulative culture. Assuming two obligatory learning stages per discrete generation, we obtain the evolutionarily stable learning schedules for the three situations where the environment is constant, fluctuates between generations, or fluctuates within generations. During each learning stage, we assume that an organism may target the optimal phenotype in the current environment by individual learning, and/or the mature phenotype of the previous generation by oblique social learning. In the absence of exogenous costs to learning, the evolutionarily stable learning schedules are predicted to be either pure social learning followed by pure individual learning ("bang-bang" control) or pure individual learning at both stages ("flat" control). Moreover, we find for each situation that the evolutionarily stable learning schedule is also the one that optimizes the learned phenotype at equilibrium. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Genetic Diversity and Selective Pressure in Hepatitis C Virus Genotypes 1–6: Significance for Direct-Acting Antiviral Treatment and Drug Resistance

    Directory of Open Access Journals (Sweden)

    Lize Cuypers

    2015-09-01

    Full Text Available Treatment with pan-genotypic direct-acting antivirals, targeting different viral proteins, is the best option for clearing hepatitis C virus (HCV infection in chronically infected patients. However, the diversity of the HCV genome is a major obstacle for the development of antiviral drugs, vaccines, and genotyping assays. In this large-scale analysis, genome-wide diversity and selective pressure was mapped, focusing on positions important for treatment, drug resistance, and resistance testing. A dataset of 1415 full-genome sequences, including genotypes 1–6 from the Los Alamos database, was analyzed. In 44% of all full-genome positions, the consensus amino acid was different for at least one genotype. Focusing on positions sharing the same consensus amino acid in all genotypes revealed that only 15% was defined as pan-genotypic highly conserved (≥99% amino acid identity and an additional 24% as pan-genotypic conserved (≥95%. Despite its large genetic diversity, across all genotypes, codon positions were rarely identified to be positively selected (0.23%–0.46% and predominantly found to be under negative selective pressure, suggesting mainly neutral evolution. For NS3, NS5A, and NS5B, respectively, 40% (6/15, 33% (3/9, and 14% (2/14 of the resistance-related positions harbored as consensus the amino acid variant related to resistance, potentially impeding treatment. For example, the NS3 variant 80K, conferring resistance to simeprevir used for treatment of HCV1 infected patients, was present in 39.3% of the HCV1a strains and 0.25% of HCV1b strains. Both NS5A variants 28M and 30S, known to be associated with resistance to the pan-genotypic drug daclatasvir, were found in a significant proportion of HCV4 strains (10.7%. NS5B variant 556G, known to confer resistance to non-nucleoside inhibitor dasabuvir, was observed in 8.4% of the HCV1b strains. Given the large HCV genetic diversity, sequencing efforts for resistance testing purposes may

  7. Significance of the Cytological Signs of Human Papillomavirus Infection in Anal Pap Smears of Human Immunodeficiency Virus-Infected Japanese Men Who Have Sex with Men

    Science.gov (United States)

    Okayama, Kaori; Okodo, Mitsuaki; Kitamura, Hiroshi; Itoda, Ichiro

    2017-11-26

    Purpose: The incidence of invasive anal cancer (IAC) has been increasing among human immunodeficiency virus (HIV)-positive men who have sex with men (MSM). Although cytological diagnosis is the modality of choice for screening cases of IAC, it is associated with lower sensitivity and specificity. Therefore, the present study aimed to evaluate new cytological signs of human papillomavirus (HPV) infection that may contribute to improving anal cytology. Methods: Anal cytology and HPV testing were performed using SurePath liquid-based cytology on samples obtained from 37 HIV-positive Japanese MSM. Subsequently, a histological biopsy based on high-resolution anoscopy was performed in MSM with abnormal cytological findings indicative of atypical squamous cells of undetermined significance (ASC-US) +. Also, anal Papanicolaou (Pap) smears were performed to determine cellularity, presence of dysplastic squamous cells, and other cytological signs of HPV infection. Results: Of the 37 MSM who underwent anal cytology, six tested negative for intraepithelial lesion or malignancy, three cases exhibited ASC-US, 17 exhibited low-grade squamous intraepithelial lesion (LSIL), nine exhibited high-grade squamous intraepithelial lesion (HSIL), and two remained undiagnosed. The anal Pap smears of 28 (96.6%) of the 29 MSM with abnormal cytological findings of ASC-US+ exhibited anal intraepithelial neoplasia (AIN), as revealed by histological biopsy. The median value (minimum–maximum) of the cellularity of anal Pap smears was 12 (0–70.5) nsc/hpf. In 26 MSM with LSIL and HSIL, the median dysplastic squamous cells count was 14 (2–152) dsc/smear and the cytological sign of HPV infection was 11 (2–71) hpv/smear. Of all anal Pap smears that revealed ASC-US+, 96.6% exhibited cytological signs of HPV infection. Compression-positive binucleated cells were the most prevalent among all cytological signs of HPV infection. Conclusion: For anal cytology, instead of considering a small number of

  8. Data from "Crossing to safety: Dispersal, colonization and mate choice in evolutionarily distinct populations of Steller sea lions, Eumetopias jubatus."

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data sets used to support analysis published by O'Corry-Crowe et al (2014) Crossing to safety: Dispersal, colonization and mate choice in evolutionarily distinct...

  9. Identification of evolutionarily conserved exons as regulated targets for the splicing activator tra2β in development.

    Directory of Open Access Journals (Sweden)

    Sushma Grellscheid

    2011-12-01

    Full Text Available Alternative splicing amplifies the information content of the genome, creating multiple mRNA isoforms from single genes. The evolutionarily conserved splicing activator Tra2β (Sfrs10 is essential for mouse embryogenesis and implicated in spermatogenesis. Here we find that Tra2β is up-regulated as the mitotic stem cell containing population of male germ cells differentiate into meiotic and post-meiotic cells. Using CLIP coupled to deep sequencing, we found that Tra2β binds a high frequency of exons and identified specific G/A rich motifs as frequent targets. Significantly, for the first time we have analysed the splicing effect of Sfrs10 depletion in vivo by generating a conditional neuronal-specific Sfrs10 knock-out mouse (Sfrs10(fl/fl; Nestin-Cre(tg/+. This mouse has defects in brain development and allowed correlation of genuine physiologically Tra2β regulated exons. These belonged to a novel class which were longer than average size and importantly needed multiple cooperative Tra2β binding sites for efficient splicing activation, thus explaining the observed splicing defects in the knockout mice. Regulated exons included a cassette exon which produces a meiotic isoform of the Nasp histone chaperone that helps monitor DNA double-strand breaks. We also found a previously uncharacterised poison exon identifying a new pathway of feedback control between vertebrate Tra2 proteins. Both Nasp-T and the Tra2a poison exon are evolutionarily conserved, suggesting they might control fundamental developmental processes. Tra2β protein isoforms lacking the RRM were able to activate specific target exons indicating an additional functional role as a splicing co-activator. Significantly the N-terminal RS1 domain conserved between flies and humans was essential for the splicing activator function of Tra2β. Versions of Tra2β lacking this N-terminal RS1 domain potently repressed the same target exons activated by full-length Tra2β protein.

  10. The Populus ARBORKNOX1 homeodomain transcription factor regulates woody growth through binding to evolutionarily conserved target genes of diverse function.

    Science.gov (United States)

    Liu, Lijun; Zinkgraf, Matthew; Petzold, H Earl; Beers, Eric P; Filkov, Vladimir; Groover, Andrew

    2015-01-01

    The class I KNOX homeodomain transcription factor ARBORKNOX1 (ARK1) is a key regulator of vascular cambium maintenance and cell differentiation in Populus. Currently, basic information is lacking concerning the distribution, functional characteristics, and evolution of ARK1 binding in the Populus genome. Here, we used chromatin immunoprecipitation sequencing (ChIP-seq) technology to identify ARK1 binding loci genome-wide in Populus. Computational analyses evaluated the distribution of ARK1 binding loci, the function of genes associated with bound loci, the effect of ARK1 binding on transcript levels, and evolutionary conservation of ARK1 binding loci. ARK1 binds to thousands of loci which are highly enriched proximal to the transcriptional start sites of genes of diverse functions. ARK1 target genes are significantly enriched in paralogs derived from the whole-genome salicoid duplication event. Both ARK1 and a maize (Zea mays) homolog, KNOTTED1, preferentially target evolutionarily conserved genes. However, only a small portion of ARK1 target genes are significantly differentially expressed in an ARK1 over-expression mutant. This study describes the functional characteristics and evolution of DNA binding by a transcription factor in an undomesticated tree, revealing complexities similar to those shown for transcription factors in model animal species. No claim to original US Government works. New Phytologist © 2014 New Phytologist Trust.

  11. Delayed Dosing of S-033188, a Novel Inhibitor of Influenza Virus Cap-dependent Endonuclease, Exhibited Significant Reduction of Viral Titer and Mortality in Mice Infected with Influenza A Virus

    OpenAIRE

    Fukao, Keita; Ando, Yoshinori; Noshi, Takeshi; Kawai, Makoto; Yoshida, Ryu; Shishido, Takao; Naito, Akira

    2017-01-01

    Abstract Background Both epidemic and pandemic influenza are major public health concerns, but current standard treatment limits its usage by 48 hours from onsets. Furthermore, no antiviral drug has been shown to definitively reduce serious complications, hospitalization, or mortality in a randomized clinical trial. S-033188 is an orally available small molecule inhibitor of cap-dependent endonuclease that is essential for transcription and replication of influenza A and B virus. In this stud...

  12. [Amphioxus ortholog of ECSIT, an evolutionarily conserved adaptor in the Toll and BMP signaling pathways].

    Science.gov (United States)

    Lin, Y H; Zhang, W; Li, J W; Zhang, H W; Chen, D Y

    2017-01-01

    In vertebrates, evolutionarily conserved signaling intermediate in the Toll pathway (ECSIT) interacts with the TNF-receptor associated factor 6 (TRAF6) to regulate the processing of MEKK1, activate NF-κB, and also control BMP target genes. However, the role of ECSIT in invertebrates remains largely unexplored. We performed comparative investigations of the expression, gene structure, and phylogeny of ECSIT, Toll-like receptor (TLR), and Smad4 in the cephalochordate Branchiostoma belcheri. Phylogenetic analysis indicated that, in amphioxus, ECSIT, TLR, and Smad4 form independent clusters at the base of Chordate   clusters. Interestingly, overall gene structures were comparable to those in vertebrate orthologs. Transcripts of AmphiECSIT were detectable at the mid-neural stage, and continued to be expressed in the epithelium of the pharyngeal region at later stages. In adult animals, strong expression was observed in the nerve cord, endostyle, epithelial cells of the gut and wheel organ, genital membrane of the testis, and coelom and lymphoid cavities, what is highly similar to AmphiTLR and AmphiSmad4 expression patterns during development and in adult organisms. Our data suggests that ECSIT is evolutionarily conserved. Its amphioxus ortholog functions during embryonic development and as part of the innate immune system and may be involved in TLR/BMP signaling.

  13. Evolutionary stability of mutualism: interspecific population regulation as an evolutionarily stable strategy

    Science.gov (United States)

    Holland, J. Nathaniel; DeAngelis, Donald L.; Schultz, Stewart T.

    2004-01-01

    Interspecific mutualisms are often vulnerable to instability because low benefit : cost ratios can rapidly lead to extinction or to the conversion of mutualism to parasite–host or predator–prey interactions. We hypothesize that the evolutionary stability of mutualism can depend on how benefits and costs to one mutualist vary with the population density of its partner, and that stability can be maintained if a mutualist can influence demographic rates and regulate the population density of its partner. We test this hypothesis in a model of mutualism with key features of senita cactus (Pachycereus schottii) – senita moth (Upiga virescens) interactions, in which benefits of pollination and costs of larval seed consumption to plant fitness depend on pollinator density. We show that plants can maximize their fitness by allocating resources to the production of excess flowers at the expense of fruit. Fruit abortion resulting from excess flower production reduces pre–adult survival of the pollinating seed–consumer, and maintains its density beneath a threshold that would destabilize the mutualism. Such a strategy of excess flower production and fruit abortion is convergent and evolutionarily stable against invasion by cheater plants that produce few flowers and abort few to no fruit. This novel mechanism of achieving evolutionarily stable mutualism, namely interspecific population regulation, is qualitatively different from other mechanisms invoking partner choice or selective rewards, and may be a general process that helps to preserve mutualistic interactions in nature.

  14. The lateral line confers evolutionarily derived sleep loss in the Mexican cavefish.

    Science.gov (United States)

    Jaggard, James; Robinson, Beatriz G; Stahl, Bethany A; Oh, Ian; Masek, Pavel; Yoshizawa, Masato; Keene, Alex C

    2017-01-15

    Sleep is an essential behavior exhibited by nearly all animals, and disruption of this process is associated with an array of physiological and behavioral deficits. Sleep is defined by changes in sensory gating that reduce sensory input to the brain, but little is known about the neural basis for interactions between sleep and sensory processing. Blind Mexican cavefish comprise an extant surface dwelling form and 29 cave morphs that have independently evolved increased numbers of mechanoreceptive lateral line neuromasts and convergent evolution of sleep loss. Ablation of the lateral line enhanced sleep in the Pachón cavefish population, suggesting that heightened sensory input underlies evolutionarily derived sleep loss. Targeted lateral line ablation and behavioral analysis localized the wake-promoting neuromasts in Pachón cavefish to superficial neuromasts of the trunk and cranial regions. Strikingly, lateral line ablation did not affect sleep in four other cavefish populations, suggesting that distinct neural mechanisms regulate the evolution of sleep loss in independently derived cavefish populations. Cavefish are subject to seasonal changes in food availability, raising the possibility that sensory modulation of sleep is influenced by metabolic state. We found that starvation promotes sleep in Pachón cavefish, and is not enhanced by lateral line ablation, suggesting that functional interactions occur between sensory and metabolic regulation of sleep. Taken together, these findings support a model where sensory processing contributes to evolutionarily derived changes in sleep that are modulated in accordance with food availability. © 2017. Published by The Company of Biologists Ltd.

  15. Putative recombination signature and significance of insertion/deletion events in the RNA-dependent RNA polymerase coding region of sugarcane yellow leaf virus.

    Science.gov (United States)

    ElSayed, Abdelaleim Ismail; Boulila, Moncef; Komor, Ewald; Zhu, Yun J

    2012-08-01

    The 5898 nucleotide single-strand RNA genome of Sugarcane yellow leaf virus (SCYLV) contains one long open reading frame, which is translated into a 120.6 kDa polyprotein. The sequences of SCYLV isolates from the two SCYLV-susceptible cultivars from Hawaii had a deletion of 48-51 nt in ORF1. SCYLV from 12 sugarcane hybrid cultivars from different origins were tested by RT-PCR using a specific set of primers, to investigate the genome segment for this deletion. Only three cultivars were found not to have the deletion (H87-4319, JA-605 and CP52-43), while SCYLV from nine cultivars (H73-6110, H87-4094, H78-7750, GT54-9, G84-47, H78-4153, H65-7052, C1051-73, Ph-8013) along with aphid (Melanaphis sacchari), which fed on SCYLV-infected H73-6110, contained a deletion of about 50 nt. The deleted sequence was located in the overlap frameshift of ORF1 and ORF2. Thus, ORFs 1 and 2 of SCYLV are translated via ribosomal frameshift and yield the 120.6 kDa viral replicase. ORF1 plays most likely a role in the replication and is a source of large variability among the virus population. To identify possible recombination events located in the RdRp domain of the Hawaiian isolates, two programs were used: RDP v.4.3 and RECCO. It is noteworthy that according both methods Haw73-6110 was found as a potential recombinant. On the other hand, opposed to the RDP package, RECCO revealed that Haw87-4094 isolate was also a recombinant whereas Haw87-4319 was not. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  16. Significance of IgG optical density ratios (index value) in single reactive anti-Dengue virus IgG capture ELISA.

    Science.gov (United States)

    Chatterjee, Shiv Sekhar; Sharma, Ankush; Choudhury, Shilpee; Chumber, Sushil Kumar; Kaur, Mandeep; Bage, Ras; Parkhe, Nittin; Khanduri, Uma

    2016-12-01

    A single reactive IgG anti-Dengue virus ELISA test in the absence of IgM antibodies or NS1 antigen may denote current infection or past exposure to the virus. To determine whether IgG index value can be used to identify true current dengue infection we conducted a prospective observational study. Suspected dengue patients (n =1745) were tested in their first specimen by MAC-ELISA, GAC-ELISA and NS1 antigen ELISA. Patients with MAC-ELISA and NS1Antigen non-reactive but GAC-ELISA reactive results (n =57) in their first test were followed up and repeated sampling was asked for IgG index values were calculated according to the manufacturer's instruction and classified as: low (2.2-2.5), medium (2.5-4.0) and high (>4.0). 16 out of 57 patients (28.1%) had low IgG Index value whereas 26 cases (45.6%) were categorized as medium and 15(26.3%) were classified as patients with high IgG index. Nine patients with paired reactive serology or antigen positive status were categorised as serologically confirmed dengue fever, 11 patients as not dengue with categorical evidence of other infections while the rest 37 casas with clinical, radiological and laboratory parameters suggestive of dengue but no serological confirmation as possible dengue. Among confirmed, possible and non-Dengue cases, 33.3, 32.4 and 0.0% had high Index value in comparison with 22.2, 29.7 and 27.3% showing low Index values, respectively. Our results suggested a high IgG response in favour of true dengue infection than past exposure while no conclusions should drawn from a low or medium reactive GAC-ELISA results in the absence of IgM antibodies and NS1 Ag.

  17. [Hepatitis B virus surface antigen reactivity in the absence of antibodies to core antigen: an atypical serological pattern having diverse significance].

    Science.gov (United States)

    Echevarría, José María; León, Pilar; Pozo, Francisco

    2004-01-01

    Reactivity for hepatitis B virus (HBV) surface antigen (HBsAg) in samples lacking antibody to the HBV core antigen (anti-HBc) may be due to either non-specific reactions or sample contamination, but it can also reflect other situations that may present clinical relevance. In Spain, the frequency described for this atypical pattern of HBV markers ranged from 0.05 to 1.3% in different series, so that it can be considered as moderately frequent. Confirmatory assays for HBsAg and tests for detecting total and IgM anti-HBc, HBV "e" antigen and viral DNA were performed on serum samples taken from 96 patients who showed reactivity for HBsAg in absence of total anti-HBc on routine studies. These samples were collected between January, 2001 and May, 2002 and were sent for study from different Spanish laboratories. Follow-up samples were also studied from selected cases. Presence of HBsAg was excluded in 70 cases (72.9%) and total anti-HBc was detected in two additional patients, so that the original results were confirmed in 24 patients (25.0%). After further investigations, two early phases of the window period of the acute HBV infection were identified, as well as a further case of chronic HBV carriage in absence of antibody response. A single case could be confirmed as due to a contamination of the aliquot of sample studied. The pattern of HBV markers and its evolution on the follow-up were the characteristic of the phenomenon known as "hepatitis B virus type 2 infection" in eight patients. No conclusions could be drawn from the remainder 12 cases, since no follow-up samples were available for study. Besides most cases respond to non-specific reactions or reflect situations of low clinical relevance, the reactivity for HBsAg in samples lacking anti-HBc should be taken into consideration and routinely investigated, since this atypical pattern can also reflect unusual, but clinically relevant facts of the HBV infection that must be noticed.

  18. The clinical significance of nucleotide G1613A and C1653T mutations in the core promoter region of hepatitis B virus

    Directory of Open Access Journals (Sweden)

    Peng-yu HUANG

    2016-04-01

    Full Text Available Objective  To evaluate the impact of hepatitis B virus (HBV genome G1613A and C1653T mutations on disease progression, viral replication capacity, and transcription activity of HBV core promoter (CP. Methods  A total of 258 patients were enrolled in the present study, including 65 patients with acute hepatitis B (AHB, 120 with chronic hepatitis B (CHB, and 73 with acute on chronic liver failure (ACLF. Serum HBV DNA was extracted from patients, and full-length HBV genome was amplified by PCR. The incidences of G1613A, C1653T and G1613A+C1653T in different groups were compared, and through functional experiments, the impact of mutants and wild-type virus on viral replication capacity and CP transcription activity was assessed. Results  Genotype B, C and D were the three detected genotypes in 285 patients, with detection rates of 22.2%, 76.2% and 1.6%, respectively. The incidences of G1613A, C1653T and G1613A+C1653T mutations increased with the disease exacerbation, and they were 13.70%, 31.80% and 45.20% in AHB patients (P<0.01, 2.30%, 16.30% and 27.40% in CHB patients (P<0.01, and 2.29%, 12.07% and 23.29% in ACLF patients (P<0.05. Compare with wild-type strain, the G1613A mutant strain of HBV increased the viral replication capacity by 6%, reduced HBsAg level and core promoter activity by 15% and 16.2%, and reduced HBeAg to undetectable level; the C1653T mutant strain increased the viral replication capacity, HBsAg level, and core promoter activity by 10%, 55% and 17.1%, respectively, and the HBeAg level was comparable to that of wild-type strain; the G1613A+C1653T mutant strain increased viral replication capacity, HBsAg level and HBeAg level by 7%, 66% and 227%, respectively, while it had no influence on core promoter activity. Conclusion The G1613A and C1653T mutation in CP region may increase HBV replication capacity and alter CP activity and HBV antigens expression, the doublet mutation of G1613A+C1653T shows synergic effect on these

  19. Virus Crystallography

    Science.gov (United States)

    Fry, Elizabeth; Logan, Derek; Stuart, David

    Crystallography provides a means of visualizing intact virus particles as well as their isolated constituent proteins and enzymes (1-3) at near-atomic resolution, and is thus an extraordinarily powerful tool in the pursuit of a fuller understanding of the functioning of these simple biological systems. We have already expanded our knowledge of virus evolution, assembly, antigenic variation, and host-cell interactions; further studies will no doubt reveal much more. Although the rewards are enormous, an intact virus structure determination is not a trivial undertaking and entails a significant scaling up in terms of time and resources through all stages of data collection and processing compared to a traditional protein crystallographic structure determination. It is the methodology required for such studies that will be the focus of this chapter. The computational requirements were satisfied in the late 1970s, and when combined with the introduction of phase improvement techniques utilizing the virus symmetry (4,5), the application of crystallography to these massive macromolecular assemblies became feasible. This led to the determination of the first virus structure (the small RNA plant virus, tomato bushy stunt virus), by Harrison and coworkers in 1978 (6). The structures of two other plant viruses followed rapidly (7,8). In the 1980s, a major focus of attention was a family of animal RNA viruses; the Picornaviridae.

  20. Human genome contains four genes homologous to transforming genes of Harvey and Kirsten murine sarcoma viruses.

    OpenAIRE

    Chang, E H; Gonda, M A; Ellis, R.W.; Scolnick, E M; Lowy, D R

    1982-01-01

    Harvey and Kirsten murine sarcoma viruses each encode a structurally and functionally related 21-kilodalton protein (p21), which is the transforming protein of each virus. Using probes from the 0.9-kilobase (kb) p21-coding region of each virus (called v-Ha-ras and v-Ki-ras, respectively), we have molecularly cloned from normal human genomic DNA the sequences that hybridize to these probes. Four evolutionarily divergent restriction endonuclease fragments were isolated. Two hybridized preferent...

  1. Evolutionarily Conserved Repulsive Guidance Role of Slit in the Silkworm Bombyx mori

    Science.gov (United States)

    Liu, Chun; Cui, Wei-Zheng; Mu, Zhi-Mei; Zhao, Xiao; Liu, Qing-Xin

    2014-01-01

    Axon guidance molecule Slit is critical for the axon repulsion in neural tissues, which is evolutionarily conserved from planarians to humans. However, the function of Slit in the silkworm Bombyx mori was unknown. Here we showed that the structure of Bombyx mori Slit (BmSlit) was different from that in most other species in its C-terminal sequence. BmSlit was localized in the midline glial cell, the neuropil, the tendon cell, the muscle and the silk gland and colocalized with BmRobo1 in the neuropil, the muscle and the silk gland. Knock-down of Bmslit by RNA interference (RNAi) resulted in abnormal development of axons and muscles. Our results suggest that BmSlit has a repulsive role in axon guidance and muscle migration. Moreover, the localization of BmSlit in the silk gland argues for its important function in the development of the silk gland. PMID:25285792

  2. Evolutionarily conserved coupling of adaptive and excitable networks mediates eukaryotic chemotaxis

    Science.gov (United States)

    Tang, Ming; Wang, Mingjie; Shi, Changji; Iglesias, Pablo A.; Devreotes, Peter N.; Huang, Chuan-Hsiang

    2014-10-01

    Numerous models explain how cells sense and migrate towards shallow chemoattractant gradients. Studies show that an excitable signal transduction network acts as a pacemaker that controls the cytoskeleton to drive motility. Here we show that this network is required to link stimuli to actin polymerization and chemotactic motility and we distinguish the various models of chemotaxis. First, signalling activity is suppressed towards the low side in a gradient or following removal of uniform chemoattractant. Second, signalling activities display a rapid shut off and a slower adaptation during which responsiveness to subsequent test stimuli decline. Simulations of various models indicate that these properties require coupled adaptive and excitable networks. Adaptation involves a G-protein-independent inhibitor, as stimulation of cells lacking G-protein function suppresses basal activities. The salient features of the coupled networks were observed for different chemoattractants in Dictyostelium and in human neutrophils, suggesting an evolutionarily conserved mechanism for eukaryotic chemotaxis.

  3. EAG2 potassium channel with evolutionarily conserved function as a brain tumor target

    Science.gov (United States)

    Huang, Xi; He, Ye; Dubuc, Adrian M.; Hashizume, Rintaro; Zhang, Wei; Reimand, Jüri; Yang, Huanghe; Wang, Tongfei A.; Stehbens, Samantha J.; Younger, Susan; Barshow, Suzanne; Zhu, Sijun; Cooper, Michael K.; Peacock, John; Ramaswamy, Vijay; Garzia, Livia; Wu, Xiaochong; Remke, Marc; Forester, Craig M.; Kim, Charles C.; Weiss, William A.; James, C. David; Shuman, Marc A.; Bader, Gary D.; Mueller, Sabine; Taylor, Michael D.; Jan, Yuh Nung; Jan, Lily Yeh

    2015-01-01

    Over 20% of the drugs for treating human diseases target ion channels, however, no cancer drug approved by the U.S. Food and Drug Administration (FDA) is intended to target an ion channel. Here, we demonstrate the evolutionarily conserved function of EAG2 potassium channel in promoting brain tumor growth and metastasis, delineate downstream pathways and uncover a mechanism for different potassium channels to functionally corporate and regulate mitotic cell volume and tumor progression. We show that EAG2 potassium channel is enriched at the trailing edge of migrating MB cells to regulate local cell volume dynamics, thereby facilitating cell motility. We identify the FDA-approved antipsychotic drug thioridazine as an EAG2 channel blocker that reduces xenografted MB growth and metastasis, and present a case report of repurposing thioridazine for treating a human patient. Our findings thus illustrate the potential of targeting ion channels in cancer treatment. PMID:26258683

  4. Rbfox proteins regulate alternative mRNA splicing through evolutionarily conserved RNA bridges.

    Science.gov (United States)

    Lovci, Michael T; Ghanem, Dana; Marr, Henry; Arnold, Justin; Gee, Sherry; Parra, Marilyn; Liang, Tiffany Y; Stark, Thomas J; Gehman, Lauren T; Hoon, Shawn; Massirer, Katlin B; Pratt, Gabriel A; Black, Douglas L; Gray, Joe W; Conboy, John G; Yeo, Gene W

    2013-12-01

    Alternative splicing (AS) enables programmed diversity of gene expression across tissues and development. We show here that binding in distal intronic regions (>500 nucleotides (nt) from any exon) by Rbfox splicing factors important in development is extensive and is an active mode of splicing regulation. Similarly to exon-proximal sites, distal sites contain evolutionarily conserved GCATG sequences and are associated with AS activation and repression upon modulation of Rbfox abundance in human and mouse experimental systems. As a proof of principle, we validated the activity of two specific Rbfox enhancers in KIF21A and ENAH distal introns and showed that a conserved long-range RNA-RNA base-pairing interaction (an RNA bridge) is necessary for Rbfox-mediated exon inclusion in the ENAH gene. Thus we demonstrate a previously unknown RNA-mediated mechanism for AS control by distally bound RNA-binding proteins.

  5. The dinoflagellates Durinskia baltica and Kryptoperidinium foliaceum retain functionally overlapping mitochondria from two evolutionarily distinct lineages

    Directory of Open Access Journals (Sweden)

    Keeling Patrick J

    2007-09-01

    Full Text Available Abtract Background The dinoflagellates Durinskia baltica and Kryptoperidinium foliaceum are distinguished by the presence of a tertiary plastid derived from a diatom endosymbiont. The diatom is fully integrated with the host cell cycle and is so altered in structure as to be difficult to recognize it as a diatom, and yet it retains a number of features normally lost in tertiary and secondary endosymbionts, most notably mitochondria. The dinoflagellate host is also reported to retain mitochondrion-like structures, making these cells unique in retaining two evolutionarily distinct mitochondria. This redundancy raises the question of whether the organelles share any functions in common or have distributed functions between them. Results We show that both host and endosymbiont mitochondrial genomes encode genes for electron transport proteins. We have characterized cytochrome c oxidase 1 (cox1, cytochrome oxidase 2 (cox2, cytochrome oxidase 3 (cox3, cytochrome b (cob, and large subunit of ribosomal RNA (LSUrRNA of endosymbiont mitochondrial ancestry, and cox1 and cob of host mitochondrial ancestry. We show that all genes are transcribed and that those ascribed to the host mitochondrial genome are extensively edited at the RNA level, as expected for a dinoflagellate mitochondrion-encoded gene. We also found evidence for extensive recombination in the host mitochondrial genes and that recombination products are also transcribed, as expected for a dinoflagellate. Conclusion Durinskia baltica and K. foliaceum retain two mitochondria from evolutionarily distinct lineages, and the functions of these organelles are at least partially overlapping, since both express genes for proteins in electron transport.

  6. RNA editing in bacteria recodes multiple proteins and regulates an evolutionarily conserved toxin-antitoxin system.

    Science.gov (United States)

    Bar-Yaacov, Dan; Mordret, Ernest; Towers, Ruth; Biniashvili, Tammy; Soyris, Clara; Schwartz, Schraga; Dahan, Orna; Pilpel, Yitzhak

    2017-10-01

    Adenosine (A) to inosine (I) RNA editing is widespread in eukaryotes. In prokaryotes, however, A-to-I RNA editing was only reported to occur in tRNAs but not in protein-coding genes. By comparing DNA and RNA sequences of Escherichia coli, we show for the first time that A-to-I editing occurs also in prokaryotic mRNAs and has the potential to affect the translated proteins and cell physiology. We found 15 novel A-to-I editing events, of which 12 occurred within known protein-coding genes where they always recode a tyrosine (TAC) into a cysteine (TGC) codon. Furthermore, we identified the tRNA-specific adenosine deaminase (tadA) as the editing enzyme of all these editing sites, thus making it the first identified RNA editing enzyme that modifies both tRNAs and mRNAs. Interestingly, several of the editing targets are self-killing toxins that belong to evolutionarily conserved toxin-antitoxin pairs. We focused on hokB, a toxin that confers antibiotic tolerance by growth inhibition, as it demonstrated the highest level of such mRNA editing. We identified a correlated mutation pattern between the edited and a DNA hard-coded Cys residue positions in the toxin and demonstrated that RNA editing occurs in hokB in two additional bacterial species. Thus, not only the toxin is evolutionarily conserved but also the editing itself within the toxin is. Finally, we found that RNA editing in hokB increases as a function of cell density and enhances its toxicity. Our work thus demonstrates the occurrence, regulation, and functional consequences of RNA editing in bacteria. © 2017 Bar-Yaacov et al.; Published by Cold Spring Harbor Laboratory Press.

  7. Costs and benefits of vertical and horizontal transmission of dengue virus.

    Science.gov (United States)

    Ruiz-Guzmán, Gloria; Ramos-Castañeda, José; Hernández-Quintero, Angélica; Contreras-Garduño, Jorge

    2016-11-15

    Parasites can be transmitted vertically and/or horizontally, but the costs or benefits for the host of infection have only been tested after horizontal transmission. Here, we report for the first time, to our knowledge, the survival, reproduction and infection of Aedes aegypti during vertical and horizontal transmission of dengue virus 2 (DENV-2). Females infected horizontally produced more eggs, with a sex ratio skewed towards males, compared with uninfected controls. However, there was no significant difference in the number of emerging adults or in survival of mothers. In contrast, dengue-infected female offspring (vertical transmission) had a shorter lifespan but there were no significant differences in the number of eggs or sex ratio, compared with controls. Finally, the corroboration of infection revealed that virus infected about 11.5% and 8.8% of pools of mothers and of daughters, respectively. These results suggest that the mode of infection and the contact with the virus has no reproductive costs to female mosquitoes, which may explain why both types of transmission are evolutionarily maintained. In addition, we suggest that more attention should be paid to the male contribution to virus dissemination within and among populations and as reservoirs of the infection for human diseases. © 2016. Published by The Company of Biologists Ltd.

  8. Most m6A RNA modifications in protein-coding regions are evolutionarily unconserved and likely nonfunctional.

    Science.gov (United States)

    Liu, Zhen; Zhang, Jianzhi

    2017-12-08

    Methylation of the adenosine base at the nitrogen-6 position (m6A) is the most prevalent internal posttranscriptional modification of mRNAs in many eukaryotes. Despite the rapid progress in the transcriptome-wide mapping of m6As, identification of proteins responsible for writing, reading, and erasing m6As, and elucidation of m6A functions in splicing, RNA stability, translation, and other processes, it is unknown whether most observed m6A modifications are functional. To address this question, we respectively analyze the evolutionary conservation of yeast and human m6As in protein-coding regions. Relative to comparable unmethylated As, m6As are overall no more conserved in yeasts and only slightly more conserved in mammals. Furthermore, yeast m6As and comparable unmethylated As have no significant difference in single nucleotide polymorphism (SNP) density or SNP site frequency spectrum. The same is true in human. The methylation status of a gene, not necessarily the specific sites methylated in the gene, is subject to purifying selection for no more than ∼20% of m6A-modified genes. These observations suggest that most m6A modifications in protein-coding regions are nonfunctional and nonadaptive, probably resulting from off-target activities of m6A methyltransferases. In addition, our reanalysis invalidates the recent claim of positive selection for newly acquired m6A modifications in human evolution. Regarding the small number of evolutionarily conserved m6As, evidence suggests that a large proportion of them are likely functional; they should be prioritized in future functional characterizations of m6As. Together, these findings have important implications for understanding the biological significance of m6A and other posttranscriptional modifications. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Clinical significance of SNP (rs2596542 in histocompatibility complex class I-related gene A promoter region among hepatitis C virus related hepatocellular carcinoma cases

    Directory of Open Access Journals (Sweden)

    Amal A. Mohamed

    2017-07-01

    Full Text Available The major histocompatibility complex class I-related gene A (MICA is an antigen induced by stress and performs an integral role in immune responses as an anti-infectious and antitumor agent. This work was designed to investigate whether (SNP rs2596542C/T in MICA promoter region is predictive of liver cirrhosis (LC and hepatocellular carcinoma (HCC or not. Forty-seven healthy controls and 94 HCV-infected patients, subdivided into 47 LC and 47 HCC subjects were enrolled in this study. SNP association was studied using real time PCR and soluble serum MICA concentration was measured using ELISA. Results showed that heterozygous genotype rs2596542CT was significantly (P = 0.022 distributed between HCC and LC related CHC patients. The sMICA was significantly higher (P = 0.0001 among HCC and LC. No significant association (P = 0.56 between rs2596542CT genotypes and sMICA levels was observed. Studying SNP rs2596542C/T association with HCC and LC susceptibility revealed that statistical significant differences (P = 0.013, P = 0.027 were only observed between SNP rs2596542C/T and each of HCC and LC, respectively, versus healthy controls, indicating that the rs2596542C/T genetic variation is not a significant contributor to HCC development in LC patients. Moreover, the T allele was considered a risk factor for HCC and LC vulnerability in HCV patients (OR = 1.93 and 2.1, respectively, while the C allele contributes to decreasing HCC risk. Therefore, SNP (rs2596542C/T in MICA promoter region and sMICA levels might be potential useful markers in the assessment of liver disease progression to LC and HCC.

  10. Lymphocyte migration through the blood-brain barrier (BBB) in feline immunodeficiency virus infection is significantly influenced by the pre-existence of virus and tumour necrosis factor (TNF)-alpha within the central nervous system (CNS): studies using an in vitro feline BBB model.

    Science.gov (United States)

    Fletcher, N F; Bexiga, M G; Brayden, D J; Brankin, B; Willett, B J; Hosie, M J; Jacque, J-M; Callanan, J J

    2009-12-01

    In human immunodeficiency virus infection, macrophage-tropic and lymphotropic viruses exist in the host. Central nervous system (CNS) infection is an early and ongoing event, important to understand when developing strategies to treat infection. Some knowledge exists on macrophage-tropic virus interactions with the blood-brain barrier (BBB), and the aim of this study was to investigate lymphotropic lentivirus interactions with the BBB. Interactions of the lymphotropic feline immunodeficiency virus (FIV) with an in vitro model of the feline BBB were evaluated in scenarios to mimic in vivo infections. Cell-free FIV crossed the BBB in very low quantities, and in the presence of tumour necrosis factor (TNF)-alpha, BBB integrity was unaffected. However, cell-associated FIV readily crossed the BBB, but BBB integrity was not significantly altered. Transmigration of uninfected and infected lymphocytes increased in response to TNF-alpha, accompanied by a moderate disruption of barrier integrity and an upregulation of vascular cell adhesion molecule-1 rather than intercellular adhesion molecule-1. Significant enhancement of migration and disruption of BBB tight junctions occurred when infected cells and TNF-alpha were added to the brain side of the BBB and this enhancement was not mediated through additional TNF-alpha production. Small quantities of virus in the brain together with TNF-alpha have the potential to stimulate greater cell and viral entry into the CNS and this is likely to involve important factors other than further TNF-alpha production. Lymphotropic lentivirus entry to the CNS is governed by many factors similar to macrophage-tropic strains.

  11. Genotype-Specific Evolution of Hepatitis E Virus

    Science.gov (United States)

    Brayne, Adam B.; Dearlove, Bethany L.; Lester, James S.; Kosakovsky Pond, Sergei L.

    2017-01-01

    ABSTRACT Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis globally. HEV comprises four genotypes with different geographic distributions and host ranges. We utilize this natural case-control study for investigating the evolution of zoonotic viruses compared to single-host viruses, using 244 near-full-length HEV genomes. Genome-wide estimates of the ratio of nonsynonymous to synonymous evolutionary changes (dN/dS ratio) located a region of overlapping reading frames, which is subject to positive selection in genotypes 3 and 4. The open reading frames (ORFs) involved have functions related to host-pathogen interaction, so genotype-specific evolution of these regions may reflect their fitness. Bayesian inference of evolutionary rates shows that genotypes 3 and 4 have significantly higher rates than genotype 1 across all ORFs. Reconstruction of the phylogenies of zoonotic genotypes demonstrates significant intermingling of isolates between hosts. We speculate that the genotype-specific differences may result from cyclical adaptation to different hosts in genotypes 3 and 4. IMPORTANCE Hepatitis E virus (HEV) is increasingly recognized as a pathogen that affects both the developing and the developed world. While most often clinically mild, HEV can be severe or fatal in certain demographics, such as expectant mothers. Like many other viral pathogens, HEV has been classified into several distinct genotypes. We show that most of the HEV genome is evolutionarily constrained. One locus of positive selection is unusual in that it encodes two distinct protein products. We are the first to detect positive selection in this overlap region. Genotype 1, which infects humans only, appears to be evolving differently from genotypes 3 and 4, which infect multiple species, possibly because genotypes 3 and 4 are unable to achieve the same fitness due to repeated host jumps. PMID:28202767

  12. Genotype-Specific Evolution of Hepatitis E Virus.

    Science.gov (United States)

    Brayne, Adam B; Dearlove, Bethany L; Lester, James S; Kosakovsky Pond, Sergei L; Frost, Simon D W

    2017-05-01

    Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis globally. HEV comprises four genotypes with different geographic distributions and host ranges. We utilize this natural case-control study for investigating the evolution of zoonotic viruses compared to single-host viruses, using 244 near-full-length HEV genomes. Genome-wide estimates of the ratio of nonsynonymous to synonymous evolutionary changes (dN/dS ratio) located a region of overlapping reading frames, which is subject to positive selection in genotypes 3 and 4. The open reading frames (ORFs) involved have functions related to host-pathogen interaction, so genotype-specific evolution of these regions may reflect their fitness. Bayesian inference of evolutionary rates shows that genotypes 3 and 4 have significantly higher rates than genotype 1 across all ORFs. Reconstruction of the phylogenies of zoonotic genotypes demonstrates significant intermingling of isolates between hosts. We speculate that the genotype-specific differences may result from cyclical adaptation to different hosts in genotypes 3 and 4.IMPORTANCE Hepatitis E virus (HEV) is increasingly recognized as a pathogen that affects both the developing and the developed world. While most often clinically mild, HEV can be severe or fatal in certain demographics, such as expectant mothers. Like many other viral pathogens, HEV has been classified into several distinct genotypes. We show that most of the HEV genome is evolutionarily constrained. One locus of positive selection is unusual in that it encodes two distinct protein products. We are the first to detect positive selection in this overlap region. Genotype 1, which infects humans only, appears to be evolving differently from genotypes 3 and 4, which infect multiple species, possibly because genotypes 3 and 4 are unable to achieve the same fitness due to repeated host jumps. Copyright © 2017 American Society for Microbiology.

  13. Evolutionarily conserved prefrontal-amygdalar dysfunction in early-life anxiety.

    Science.gov (United States)

    Birn, R M; Shackman, A J; Oler, J A; Williams, L E; McFarlin, D R; Rogers, G M; Shelton, S E; Alexander, A L; Pine, D S; Slattery, M J; Davidson, R J; Fox, A S; Kalin, N H

    2014-08-01

    Some individuals are endowed with a biology that renders them more reactive to novelty and potential threat. When extreme, this anxious temperament (AT) confers elevated risk for the development of anxiety, depression and substance abuse. These disorders are highly prevalent, debilitating and can be challenging to treat. The high-risk AT phenotype is expressed similarly in children and young monkeys and mechanistic work demonstrates that the central (Ce) nucleus of the amygdala is an important substrate. Although it is widely believed that the flow of information across the structural network connecting the Ce nucleus to other brain regions underlies primates' capacity for flexibly regulating anxiety, the functional architecture of this network has remained poorly understood. Here we used functional magnetic resonance imaging (fMRI) in anesthetized young monkeys and quietly resting children with anxiety disorders to identify an evolutionarily conserved pattern of functional connectivity relevant to early-life anxiety. Across primate species and levels of awareness, reduced functional connectivity between the dorsolateral prefrontal cortex, a region thought to play a central role in the control of cognition and emotion, and the Ce nucleus was associated with increased anxiety assessed outside the scanner. Importantly, high-resolution 18-fluorodeoxyglucose positron emission tomography imaging provided evidence that elevated Ce nucleus metabolism statistically mediates the association between prefrontal-amygdalar connectivity and elevated anxiety. These results provide new clues about the brain network underlying extreme early-life anxiety and set the stage for mechanistic work aimed at developing improved interventions for pediatric anxiety.

  14. An evolutionarily conserved glycine-tyrosine motif forms a folding core in outer membrane proteins.

    Directory of Open Access Journals (Sweden)

    Marcin Michalik

    Full Text Available An intimate interaction between a pair of amino acids, a tyrosine and glycine on neighboring β-strands, has been previously reported to be important for the structural stability of autotransporters. Here, we show that the conservation of this interacting pair extends to nearly all major families of outer membrane β-barrel proteins, which are thought to have originated through duplication events involving an ancestral ββ hairpin. We analyzed the function of this motif using the prototypical outer membrane protein OmpX. Stopped-flow fluorescence shows that two folding processes occur in the millisecond time regime, the rates of which are reduced in the tyrosine mutant. Folding assays further demonstrate a reduction in the yield of folded protein for the mutant compared to the wild-type, as well as a reduction in thermal stability. Taken together, our data support the idea of an evolutionarily conserved 'folding core' that affects the folding, membrane insertion, and thermal stability of outer membrane protein β-barrels.

  15. Genetic differentiation and selection against migrants in evolutionarily replicated extreme environments.

    Science.gov (United States)

    Plath, Martin; Pfenninger, Markus; Lerp, Hannes; Riesch, Rüdiger; Eschenbrenner, Christoph; Slattery, Patrick A; Bierbach, David; Herrmann, Nina; Schulte, Matthias; Arias-Rodriguez, Lenin; Rimber Indy, Jeane; Passow, Courtney; Tobler, Michael

    2013-09-01

    We investigated mechanisms of reproductive isolation in livebearing fishes (genus Poecilia) inhabiting sulfidic and nonsulfidic habitats in three replicate river drainages. Although sulfide spring fish convergently evolved divergent phenotypes, it was unclear if mechanisms of reproductive isolation also evolved convergently. Using microsatellites, we found strongly reduced gene flow between adjacent populations from different habitat types, suggesting that local adaptation to sulfidic habitats repeatedly caused the emergence of reproductive isolation. Reciprocal translocation experiments indicate strong selection against immigrants into sulfidic waters, but also variation among drainages in the strength of selection against immigrants into nonsulfidic waters. Mate choice experiments revealed the evolution of assortative mating preferences in females from nonsulfidic but not from sulfidic habitats. The inferred strength of sexual selection against immigrants (RI(s)) was negatively correlated with the strength of natural selection (RI(m)), a pattern that could be attributed to reinforcement, whereby natural selection strengthens behavioral isolation due to reduced hybrid fitness. Overall, reproductive isolation and genetic differentiation appear to be replicated and direct consequences of local adaptation to sulfide spring environments, but the relative contributions of different mechanisms of reproductive isolation vary across these evolutionarily independent replicates, highlighting both convergent and nonconvergent evolutionary trajectories of populations in each drainage. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  16. Honesty and cheating in cleaning symbioses: evolutionarily stable strategies defined by variable pay-offs.

    Science.gov (United States)

    Freckleton, Robert P; Côté, Isabelle M

    2003-01-01

    Game-theory models have indicated that the evolution of mixed strategies of cheating and honesty in many mutualisms is unlikely. Moreover, the mutualistic nature of interspecific interactions has often been difficult to demonstrate empirically. We present a game-theory analysis that addresses these issues using cleaning symbioses among fishes as a model system. We show that the assumption of constant pay-offs in existing models prevents the evolution of evolutionarily stable mixed strategies of cheating and honesty. However, when interaction pay-offs are assumed to be density dependent, mixed strategies of cheating and honesty become possible. In nature, cheating by clients often takes the form of retaliation by clients against cheating cleaners, and we show that mixed strategies of cheating and honesty evolve within the cleaner population when clients retaliate. The dynamics of strategies include both negative and positive effects of interactions, as well as density-dependent interactions. Consequently, the effects of perturbations to the model are nonlinear. In particular, we show that under certain conditions the removal of cleaners may have little impact on client populations. This indicates that the underlying mutualistic nature of some interspecific interactions may be difficult to demonstrate using simple manipulation experiments. PMID:12614580

  17. The effect of travel loss on evolutionarily stable distributions of populations in space.

    Science.gov (United States)

    Deangelis, Donald L; Wolkowicz, Gail S K; Lou, Yuan; Jiang, Yuexin; Novak, Mark; Svanbäck, Richard; Araújo, Márcio S; Jo, Youngseung; Cleary, Erin A

    2011-07-01

    A key assumption of the ideal free distribution (IFD) is that there are no costs in moving between habitat patches. However, because many populations exhibit more or less continuous population movement between patches and traveling cost is a frequent factor, it is important to determine the effects of costs on expected population movement patterns and spatial distributions. We consider a food chain (tritrophic or bitrophic) in which one species moves between patches, with energy cost or mortality risk in movement. In the two-patch case, assuming forced movement in one direction, an evolutionarily stable strategy requires bidirectional movement, even if costs during movement are high. In the N-patch case, assuming that at least one patch is linked bidirectionally to all other patches, optimal movement rates can lead to source-sink dynamics where patches with negative growth rates are maintained by other patches with positive growth rates. As well, dispersal between patches is not balanced (even in the two-patch case), leading to a deviation from the IFD. Our results indicate that cost-associated forced movement can have important consequences for spatial metapopulation dynamics. Relevance to marine reserve design and the study of stream communities subject to drift is discussed.

  18. The evolutionarily conserved E3 ubiquitin ligase AtCHIP contributes to plant immunity

    Directory of Open Access Journals (Sweden)

    Xin eLi

    2016-03-01

    Full Text Available Plants possess a sophisticated immune system to recognize and respond to microbial threats in their environment. The level of immune signaling must be tightly regulated so that immune responses can be quickly activated in the presence of pathogens, while avoiding autoimmunity. HSP90s, along with their diverse array of co-chaperones, forms chaperone complexes that have been shown to play both positive and negative roles in regulating the accumulation of immune receptors and regulators. In this study, we examined the role of AtCHIP, an evolutionarily conserved E3 ligase that was known to interact with chaperones including HSP90s in multicellular organisms including fruit fly, C. elegans, plants and human. Atchip knockout mutants display enhanced disease susceptibility to a virulent oomycete pathogen, and overexpression of AtCHIP causes enhanced disease resistance at low temperature. Although CHIP was reported to target HSP90 for ubiquitination and degradation, accumulation of HSP90.3 was not affected in Atchip plants. In addition, protein accumulation of nucleotide-binding, leucine-rich repeat domain immune receptor (NLR SNC1 is not altered in Atchip mutant. Thus, while AtCHIP plays a role in immunity, it does not seem to regulate the turnover of HSP90 or SNC1. Further investigation is needed in order to determine the exact mechanism behind AtCHIP’s role in regulating plant immune responses.

  19. A comprehensive test of evolutionarily increased competitive ability in a highly invasive plant species

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    Joshi, Srijana; Gruntman, Michal; Bilton, Mark; Seifan, Merav; Tielbörger, Katja

    2014-01-01

    Background and Aims A common hypothesis to explain plants' invasive success is that release from natural enemies in the introduced range selects for reduced allocation to resistance traits and a subsequent increase in resources available for growth and competitive ability (evolution of increased competitive ability, EICA). However, studies that have investigated this hypothesis have been incomplete as they either did not test for all aspects of competitive ability or did not select appropriate competitors. Methods Here, the prediction of increased competitive ability was examined with the invasive plant Lythrum salicaria (purple loosestrife) in a set of common-garden experiments that addressed these aspects by carefully distinguishing between competitive effect and response of invasive and native plants, and by using both intraspecific and interspecific competition settings with a highly vigorous neighbour, Urtica dioica (stinging nettle), which occurs in both ranges. Key Results While the intraspecific competition results showed no differences in competitive effect or response between native and invasive plants, the interspecific competition experiment revealed greater competitive response and effect of invasive plants in both biomass and seed production. Conclusions The use of both intra- and interspecific competition experiments in this study revealed opposing results. While the first experiment refutes the EICA hypothesis, the second shows strong support for it, suggesting evolutionarily increased competitive ability in invasive populations of L. salicaria. It is suggested that the use of naturally co-occurring heterospecifics, rather than conspecifics, may provide a better evaluation of the possible evolutionary shift towards greater competitive ability. PMID:25301818

  20. Sperm protein "DE" mediates gamete fusion through an evolutionarily conserved site of the CRISP family.

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    Ellerman, Diego A; Cohen, Débora J; Da Ros, Vanina G; Morgenfeld, Mauro M; Busso, Dolores; Cuasnicú, Patricia S

    2006-09-01

    The first member of the cysteine-rich secretory protein (CRISP) family was described by our laboratory in the rat epididymis, and it is known as DE or CRISP-1. Since then, numerous CRISPs exhibiting a high amino acid sequence similarity have been identified in animals, plants and fungi, although their functions remain largely unknown. CRISP-1 proteins are candidates to mediate gamete fusion in the rat, mouse and human through their binding to complementary sites on the egg surface. To elucidate the molecular mechanisms underlying CRISP-1 function, in the present work, deletion mutants of protein DE were generated and examined for their ability to bind to the rat egg and interfere with gamete fusion. Results revealed that the egg-binding ability of DE resides within a 45-amino acid N-terminal region containing the two motifs of the CRISP family named Signature 1 and Signature 2. Subsequent assays using synthetic peptides and other CRISPs support that the egg-binding site of DE falls in the 12-amino-acid region corresponding to Signature 2. The interesting finding that the binding site of DE resides in an evolutionarily conserved region of the molecule provides novel information on the molecular mechanisms underlying CRISP-1 function in gamete fusion with important implications on the structure-function relationship of other members of the widely distributed CRISP family.

  1. Specific expression of LATERAL SUPPRESSOR is controlled by an evolutionarily conserved 3' enhancer.

    Science.gov (United States)

    Raatz, Bodo; Eicker, Andrea; Schmitz, Gregor; Fuss, Elisabeth; Müller, Dörte; Rossmann, Susanne; Theres, Klaus

    2011-11-01

    Aerial plant architecture is largely based on the activity of axillary meristems (AMs), initiated in the axils of leaves. The Arabidopsis gene LATERAL SUPPRESSOR (LAS), which is expressed in well-defined domains at the adaxial boundary of leaf primordia, is a key regulator of AM formation. The precise definition of organ boundaries is an essential step for the formation of new organs in general and for meristem initiation; however, mechanisms leading to these specific patterns are not well understood. To increase understanding of how the highly specific transcript accumulation in organ boundary regions is established, we investigated the LAS promoter. Analysis of deletion constructs revealed that an essential enhancer necessary for complementation is situated about 3.2 kb downstream of the LAS open reading frame. This enhancer is sufficient to confer promoter specificity as upstream sequences in LAS could be replaced by non-specific promoters, such as the 35S minimal promoter. Further promoter swapping experiments using the PISTILLATA or the full 35S promoter demonstrated that the LAS 3' enhancer also has suppressor functions, largely overwriting the activity of different 5' promoters. Phylogenetic analyses suggest that LAS function and regulation are evolutionarily highly conserved. Homologous elements in downstream regulatory sequences were found in all LAS orthologs, including grasses. Transcomplementation experiments demonstrated the functional conservation of non-coding sequences between Solanum lycopersicum (tomato) and Arabidopsis. In summary, our results show that a highly conserved enhancer/suppressor element is the main regulatory module conferring the boundary-specific expression of LAS. © 2011 The Authors. The Plant Journal © 2011 Blackwell Publishing Ltd.

  2. FGF signaling inhibitor, SPRY4, is evolutionarily conserved target of WNT signaling pathway in progenitor cells.

    Science.gov (United States)

    Katoh, Yuriko; Katoh, Masaru

    2006-03-01

    WNT, FGF and Hedgehog signaling pathways network together during embryogenesis, tissue regeneration, and carcinogenesis. FGF16, FGF18, and FGF20 genes are targets of WNT-mediated TCF/LEF-beta-catenin-BCL9/BCL9L-PYGO transcriptional complex. SPROUTY (SPRY) and SPRED family genes encode inhibitors for receptor tyrosine kinase signaling cascades, such as those of FGF receptor family members and EGF receptor family members. Here, transcriptional regulation of SPRY1, SPRY2, SPRY3, SPRY4, SPRED1, SPRED2, and SPRED3 genes by WNT/beta-catenin signaling cascade was investigated by using bioinformatics and human intelligence (humint). Because double TCF/LEF-binding sites were identified within the 5'-promoter region of human SPRY4 gene, comparative genomics analyses on SPRY4 orthologs were further performed. SPRY4-FGF1 locus at human chromosome 5q31.3 and FGF2-NUDT6-SPATA5-SPRY1 locus at human chromosome 4q27-q28.1 were paralogous regions within the human genome. Chimpanzee SPRY4 gene was identified within NW_107083.1 genome sequence. Human, chimpanzee, rat and mouse SPRY4 orthologs, consisting of three exons, were well conserved. SPRY4 gene was identified as the evolutionarily conserved target of WNT/beta-catenin signaling pathway based on the conservation of double TCF/LEF-binding sites within 5'-promoter region of mammalian SPRY4 orthologs. Human SPRY4 mRNA was expressed in embryonic stem (ES) cells, brain, pancreatic islet, colon cancer, head and neck tumor, melanoma, and pancreatic cancer. WNT signaling activation in progenitor cells leads to the growth regulation of progenitor cells themselves through SPRY4 induction, and also to the growth stimulation of proliferating cells through FGF secretion. Epigenetic silencing and loss-of-function mutations of SPRY4 gene in progenitor cells could lead to carcinogenesis. SPRY4 is the pharmacogenomics target in the fields of oncology and regenerative medicine.

  3. Damping capacity is evolutionarily conserved in the radial silk of orb-weaving spiders.

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    Kelly, Sean P; Sensenig, Andrew; Lorentz, Kimberly A; Blackledge, Todd A

    2011-09-01

    Orb-weaving spiders depend upon their two-dimensional silk traps to stop insects in mid flight. While the silks used to construct orb webs must be extremely tough to absorb the tremendous kinetic energy of insect prey, webs must also minimize the return of that energy to prey to prevent insects from bouncing out of oscillating webs. We therefore predict that the damping capacity of major ampullate spider silk, which forms the supporting frames and radial threads of orb webs, should be evolutionarily conserved among orb-weaving spiders. We test this prediction by comparing silk from six diverse species of orb spiders. Silk was taken directly from the radii of orb webs and a Nano Bionix test system was used either to sequentially extend the silk to 25% strain in 5% increments while relaxing it fully between each cycle, or to pull virgin silk samples to 15% strain. Damping capacity was then calculated as the percent difference in loading and unloading energies. Damping capacity increased after yield for all species and typically ranged from 40 to 50% within each cycle for sequentially pulled silk and from 50 to 70% for virgin samples. Lower damping at smaller strains may allow orb webs to withstand minor perturbations from wind and small prey while still retaining the ability to capture large insects. The similarity in damping capacity of silk from the radii spun by diverse spiders highlights the importance of energy absorption by silk for orb-weaving spiders. Copyright © 2011 Elsevier GmbH. All rights reserved.

  4. Prediction of enzyme function based on 3D templates of evolutionarily important amino acids

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    Chen Brian Y

    2008-01-01

    Full Text Available Abstract Background Structural genomics projects such as the Protein Structure Initiative (PSI yield many new structures, but often these have no known molecular functions. One approach to recover this information is to use 3D templates – structure-function motifs that consist of a few functionally critical amino acids and may suggest functional similarity when geometrically matched to other structures. Since experimentally determined functional sites are not common enough to define 3D templates on a large scale, this work tests a computational strategy to select relevant residues for 3D templates. Results Based on evolutionary information and heuristics, an Evolutionary Trace Annotation (ETA pipeline built templates for 98 enzymes, half taken from the PSI, and sought matches in a non-redundant structure database. On average each template matched 2.7 distinct proteins, of which 2.0 share the first three Enzyme Commission digits as the template's enzyme of origin. In many cases (61% a single most likely function could be predicted as the annotation with the most matches, and in these cases such a plurality vote identified the correct function with 87% accuracy. ETA was also found to be complementary to sequence homology-based annotations. When matches are required to both geometrically match the 3D template and to be sequence homologs found by BLAST or PSI-BLAST, the annotation accuracy is greater than either method alone, especially in the region of lower sequence identity where homology-based annotations are least reliable. Conclusion These data suggest that knowledge of evolutionarily important residues improves functional annotation among distant enzyme homologs. Since, unlike other 3D template approaches, the ETA method bypasses the need for experimental knowledge of the catalytic mechanism, it should prove a useful, large scale, and general adjunct to combine with other methods to decipher protein function in the structural proteome.

  5. Unique amino acid signatures that are evolutionarily conserved distinguish simple-type, epidermal and hair keratins

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    Strnad, Pavel; Usachov, Valentyn; Debes, Cedric; Gräter, Frauke; Parry, David A. D.; Omary, M. Bishr

    2011-01-01

    Keratins (Ks) consist of central α-helical rod domains that are flanked by non-α-helical head and tail domains. The cellular abundance of keratins, coupled with their selective cell expression patterns, suggests that they diversified to fulfill tissue-specific functions although the primary structure differences between them have not been comprehensively compared. We analyzed keratin sequences from many species: K1, K2, K5, K9, K10, K14 were studied as representatives of epidermal keratins, and compared with K7, K8, K18, K19, K20 and K31, K35, K81, K85, K86, which represent simple-type (single-layered or glandular) epithelial and hair keratins, respectively. We show that keratin domains have striking differences in their amino acids. There are many cysteines in hair keratins but only a small number in epidermal keratins and rare or none in simple-type keratins. The heads and/or tails of epidermal keratins are glycine and phenylalanine rich but alanine poor, whereas parallel domains of hair keratins are abundant in prolines, and those of simple-type epithelial keratins are enriched in acidic and/or basic residues. The observed differences between simple-type, epidermal and hair keratins are highly conserved throughout evolution. Cysteines and histidines, which are infrequent keratin amino acids, are involved in de novo mutations that are markedly overrepresented in keratins. Hence, keratins have evolutionarily conserved and domain-selectively enriched amino acids including glycine and phenylalanine (epidermal), cysteine and proline (hair), and basic and acidic (simple-type epithelial), which reflect unique functions related to structural flexibility, rigidity and solubility, respectively. Our findings also support the importance of human keratin ‘mutation hotspot’ residues and their wild-type counterparts. PMID:22215855

  6. A comprehensive test of evolutionarily increased competitive ability in a highly invasive plant species.

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    Joshi, Srijana; Gruntman, Michal; Bilton, Mark; Seifan, Merav; Tielbörger, Katja

    2014-12-01

    A common hypothesis to explain plants' invasive success is that release from natural enemies in the introduced range selects for reduced allocation to resistance traits and a subsequent increase in resources available for growth and competitive ability (evolution of increased competitive ability, EICA). However, studies that have investigated this hypothesis have been incomplete as they either did not test for all aspects of competitive ability or did not select appropriate competitors. Here, the prediction of increased competitive ability was examined with the invasive plant Lythrum salicaria (purple loosestrife) in a set of common-garden experiments that addressed these aspects by carefully distinguishing between competitive effect and response of invasive and native plants, and by using both intraspecific and interspecific competition settings with a highly vigorous neighbour, Urtica dioica (stinging nettle), which occurs in both ranges. While the intraspecific competition results showed no differences in competitive effect or response between native and invasive plants, the interspecific competition experiment revealed greater competitive response and effect of invasive plants in both biomass and seed production. The use of both intra- and interspecific competition experiments in this study revealed opposing results. While the first experiment refutes the EICA hypothesis, the second shows strong support for it, suggesting evolutionarily increased competitive ability in invasive populations of L. salicaria. It is suggested that the use of naturally co-occurring heterospecifics, rather than conspecifics, may provide a better evaluation of the possible evolutionary shift towards greater competitive ability. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Unifying the genomics-based classes of cancer fusion gene partners: large cancer fusion genes are evolutionarily conserved.

    Science.gov (United States)

    Pava, Libia M; Morton, Daniel T; Chen, Ren; Blanck, George

    2012-11-01

    Genes that fuse to cause cancer have been studied to determine molecular bases for proliferation, to develop diagnostic tools, and as targets for drugs. To facilitate identification of additional, cancer fusion genes, following observation of a chromosomal translocation, we have characterized the genomic features of the fusion gene partners. Previous work indicated that cancer fusion gene partners, are either large or evolutionarily conserved in comparison to the neighboring genes in the region of a chromosomal translocation. These results raised the question of whether large cancer fusion gene partners were also evolutionarily conserved. We developed two methods for quantifying evolutionary conservation values, allowing the conclusion that both large and small cancer fusion gene partners are more evolutionarily conserved than their neighbors. Additionally, we determined that cancer fusion gene partners have more 3' untranslated region secondary structures than do their neighbors. Coupled with previous algorithms, with or without transcriptome approaches, we expect these results to assist in the rapid and efficient use of chromosomal translocations to identify cancer fusion genes. The above parameters for any gene of interest can be accessed at www.cancerfusiongenes.com.

  8. Ebola Virus and Marburg Virus

    Science.gov (United States)

    Ebola virus and Marburg virus Overview Ebola virus and Marburg virus are related viruses that cause hemorrhagic fevers — illnesses marked by severe bleeding (hemorrhage), organ failure and, in many ...

  9. The Need for Evolutionarily Rational Disease Interventions: Vaccination Can Select for Higher Virulence.

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    Mike Boots

    2015-08-01

    Full Text Available There is little doubt evolution has played a major role in preventing the control of infectious disease through antibiotic and insecticide resistance, but recent theory suggests disease interventions such as vaccination may lead to evolution of more harmful parasites. A new study published in PLOS Biology by Andrew Read and colleagues shows empirically that vaccination against Marek's disease has favored higher virulence; without intervention, the birds die too quickly for any transmission to occur, but vaccinated hosts can both stay alive longer and shed the virus. This is an elegant empirical demonstration of how evolutionary theory can predict potentially dangerous responses of infectious disease to human interventions.

  10. [The clinical significance of serum Epstein-Barr virus-determined nuclear antigen 1 (EBNA1)/latent membrane protein 1 (LMP1) assay in patients with nasal type extranodal NK/T-cell lymphoma].

    Science.gov (United States)

    Yao, Na; Cui, Xueying; Wang, Jingwen

    2015-02-01

    To explore the clinical significance of the serum Epstein-Barr virus-determined nuclear antigen 1 (EBNA1)/latent membrane protein 1 (LMP1) in patients with extranodal NK/T-cell lymphoma, nasal type (ENKL). The serum EBNA1 and LMP1 were detected by real-time PCR in 36 ENKL patients hospitalized in Beijing Tongren Hospital from August 2010 to August 2013. Twenty healthy volunteers were recruited as controls. The median serum EBNA1 was 1.9×10(4) (ranged from 0 to 11.0×10(4)) copies/µl in ENKL patients and 8.0 (ranged from 0 to 43.8) copies/µl in healthy volunteers. The median serum LMP1 was 3.9×10(3) (ranged from 118.3 to 24.0×10(3)) copies/µl in ENKL patients and 3.3 (ranged from 0 to 33.3) copies/µl in healthy volunteers. Both EBNA1 and LMP1 were higher in ENKL patients than healthy volunteers (all P < 0.01). The median EBNA1 and LMP1 in ENKL patients posttreatment were 1.0×10(3) (ranged from 0 to 2.0 × 10(3)) copies/µl and 300.8 (ranged from 0 to 825.7) copies/µl respectively, which were both significantly decreased than pretreatment (all P < 0.05). The EBNA1 and LMP1 were decreased in effective treatment group versus ineffective treatment group (P < 0.05). The serum EBNA1 and LMP1 were positively correlated with lactic dehydrogenase (LDH) level (r = 0.364,0.546; P = 0.040,0.012). (1) The measurement of EBNA1/LMP1 may be useful in evaluating the therapeutic effect. (2) The serum EBNA1/LMP1 may reflect the tumor load in ENKL patients.

  11. An Evolutionarily Young Polar Bear (Ursus maritimus) Endogenous Retrovirus Identified from Next Generation Sequence Data.

    Science.gov (United States)

    Tsangaras, Kyriakos; Mayer, Jens; Alquezar-Planas, David E; Greenwood, Alex D

    2015-11-24

    Transcriptome analysis of polar bear (Ursus maritimus) tissues identified sequences with similarity to Porcine Endogenous Retroviruses (PERV). Based on these sequences, four proviral copies and 15 solo long terminal repeats (LTRs) of a newly described endogenous retrovirus were characterized from the polar bear draft genome sequence. Closely related sequences were identified by PCR analysis of brown bear (Ursus arctos) and black bear (Ursus americanus) but were absent in non-Ursinae bear species. The virus was therefore designated UrsusERV. Two distinct groups of LTRs were observed including a recombinant ERV that contained one LTR belonging to each group indicating that genomic invasions by at least two UrsusERV variants have recently occurred. Age estimates based on proviral LTR divergence and conservation of integration sites among ursids suggest the viral group is only a few million years old. The youngest provirus was polar bear specific, had intact open reading frames (ORFs) and could potentially encode functional proteins. Phylogenetic analyses of UrsusERV consensus protein sequences suggest that it is part of a pig, gibbon and koala retrovirus clade. The young age estimates and lineage specificity of the virus suggests UrsusERV is a recent cross species transmission from an unknown reservoir and places the viral group among the youngest of ERVs identified in mammals.

  12. An Evolutionarily Young Polar Bear (Ursus maritimus Endogenous Retrovirus Identified from Next Generation Sequence Data

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    Kyriakos Tsangaras

    2015-11-01

    Full Text Available Transcriptome analysis of polar bear (Ursus maritimus tissues identified sequences with similarity to Porcine Endogenous Retroviruses (PERV. Based on these sequences, four proviral copies and 15 solo long terminal repeats (LTRs of a newly described endogenous retrovirus were characterized from the polar bear draft genome sequence. Closely related sequences were identified by PCR analysis of brown bear (Ursus arctos and black bear (Ursus americanus but were absent in non-Ursinae bear species. The virus was therefore designated UrsusERV. Two distinct groups of LTRs were observed including a recombinant ERV that contained one LTR belonging to each group indicating that genomic invasions by at least two UrsusERV variants have recently occurred. Age estimates based on proviral LTR divergence and conservation of integration sites among ursids suggest the viral group is only a few million years old. The youngest provirus was polar bear specific, had intact open reading frames (ORFs and could potentially encode functional proteins. Phylogenetic analyses of UrsusERV consensus protein sequences suggest that it is part of a pig, gibbon and koala retrovirus clade. The young age estimates and lineage specificity of the virus suggests UrsusERV is a recent cross species transmission from an unknown reservoir and places the viral group among the youngest of ERVs identified in mammals.

  13. Evolutionarily conserved interaction between the phosphoproteins and X proteins of bornaviruses from different vertebrate species.

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    Kan Fujino

    Full Text Available Bornavirus, a non-segmented, negative-strand RNA viruses, is currently classified into several genetically distinct genotypes, such as Borna disease virus (BDV and avian bornaviruses (ABVs. Recent studies revealed that bornavirus genotypes show unique sequence variability in the putative 5' untranslated region (5' UTR of X/P mRNA, a bicistronic mRNA for the X protein and phosphoprotein (P. In this study, to understand the evolutionary relationship among the bornavirus genotypes, we investigated the functional interaction between the X and P proteins of four bornavirus genotypes, BDV, ABV genotype 4 and 5 and reptile bornavirus (RBV, the putative 5' UTRs of which exhibit variation in the length. Immunofluorescence and immunoprecipitation analyses using mammalian and avian cell lines revealed that the X proteins of bornaviruses conserve the ability to facilitate the export of P from the nucleus to the cytoplasm via interaction with P. Furthermore, we showed that inter-genotypic interactions may occur between X and P among the genotypes, except for X of RBV. In addition, a BDV minireplicon assay demonstrated that the X and P proteins of ABVs, but not RBV, can affect the polymerase activity of BDV. This study demonstrates that bornaviruses may have conserved the fundamental function of a regulatory protein during their evolution, whereas RBV has evolved distinctly from the other bornavirus genotypes.

  14. An Evolutionarily Young Polar Bear (Ursus maritimus) Endogenous Retrovirus Identified from Next Generation Sequence Data

    Science.gov (United States)

    Tsangaras, Kyriakos; Mayer, Jens; Alquezar-Planas, David E.; Greenwood, Alex D.

    2015-01-01

    Transcriptome analysis of polar bear (Ursus maritimus) tissues identified sequences with similarity to Porcine Endogenous Retroviruses (PERV). Based on these sequences, four proviral copies and 15 solo long terminal repeats (LTRs) of a newly described endogenous retrovirus were characterized from the polar bear draft genome sequence. Closely related sequences were identified by PCR analysis of brown bear (Ursus arctos) and black bear (Ursus americanus) but were absent in non-Ursinae bear species. The virus was therefore designated UrsusERV. Two distinct groups of LTRs were observed including a recombinant ERV that contained one LTR belonging to each group indicating that genomic invasions by at least two UrsusERV variants have recently occurred. Age estimates based on proviral LTR divergence and conservation of integration sites among ursids suggest the viral group is only a few million years old. The youngest provirus was polar bear specific, had intact open reading frames (ORFs) and could potentially encode functional proteins. Phylogenetic analyses of UrsusERV consensus protein sequences suggest that it is part of a pig, gibbon and koala retrovirus clade. The young age estimates and lineage specificity of the virus suggests UrsusERV is a recent cross species transmission from an unknown reservoir and places the viral group among the youngest of ERVs identified in mammals. PMID:26610552

  15. Hospital and community ampicillin-resistant Enterococcus faecium are evolutionarily closely linked but have diversified through niche adaptation.

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    Marieke J A de Regt

    Full Text Available BACKGROUND: Ampicillin-resistant Enterococcus faecium (ARE has emerged as a nosocomial pathogen. Here, we quantified ARE carriage in different community sources and determined genetic relatedness with hospital ARE. METHODS AND RESULTS: ARE was recovered from rectal swabs of 24 of 79 (30% dogs, 11 of 85 (13% cats and 0 of 42 horses and from 3 of 40 (8% faecal samples of non-hospitalized humans receiving amoxicillin. Multi-locus Sequence Typing revealed 21 sequence types (STs, including 5 STs frequently associated with hospital-acquired infections. Genes previously found to be enriched in hospital ARE, such as IS16, orf903, orf905, orf907, were highly prevalent in community ARE (≥79%, while genes with a proposed role in pathogenesis, such as esp, hyl and ecbA, were found rarely (≤5% in community isolates. Comparative genome analysis of 2 representative dog isolates revealed that the dog strain of ST192 was evolutionarily closely linked to two previously sequenced hospital ARE, but had, based on gene content, more genes in common with the other, evolutionarily more distantly related, dog strain (ST266. CONCLUSION: ARE were detected in dogs, cats and sporadically in healthy humans, with evolutionary linkage to hospital ARE. Yet, their accessory genome has diversified, probably as a result of niche adaptation.

  16. An evolutionarily conserved gene, FUWA, plays a role in determining panicle architecture, grain shape and grain weight in rice.

    Science.gov (United States)

    Chen, Jun; Gao, He; Zheng, Xiao-Ming; Jin, Mingna; Weng, Jian-Feng; Ma, Jin; Ren, Yulong; Zhou, Kunneng; Wang, Qi; Wang, Jie; Wang, Jiu-Lin; Zhang, Xin; Cheng, Zhijun; Wu, Chuanyin; Wang, Haiyang; Wan, Jian-Min

    2015-08-01

    Plant breeding relies on creation of novel allelic combinations for desired traits. Identification and utilization of beneficial alleles, rare alleles and evolutionarily conserved genes in the germplasm (referred to as 'hidden' genes) provide an effective approach to achieve this goal. Here we show that a chemically induced null mutation in an evolutionarily conserved gene, FUWA, alters multiple important agronomic traits in rice, including panicle architecture, grain shape and grain weight. FUWA encodes an NHL domain-containing protein, with preferential expression in the root meristem, shoot apical meristem and inflorescences, where it restricts excessive cell division. Sequence analysis revealed that FUWA has undergone a bottleneck effect, and become fixed in landraces and modern cultivars during domestication and breeding. We further confirm a highly conserved role of FUWA homologs in determining panicle architecture and grain development in rice, maize and sorghum through genetic transformation. Strikingly, knockdown of the FUWA transcription level by RNA interference results in an erect panicle and increased grain size in both indica and japonica genetic backgrounds. This study illustrates an approach to create new germplasm with improved agronomic traits for crop breeding by tapping into evolutionary conserved genes. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  17. A leafhopper-transmissible DNA virus with novel evolutionary lineage in the family geminiviridae implicated in grapevine redleaf disease by next-generation sequencing.

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    Sudarsana Poojari

    Full Text Available A graft-transmissible disease displaying red veins, red blotches and total reddening of leaves in red-berried wine grape (Vitis vinifera L. cultivars was observed in commercial vineyards. Next-generation sequencing technology was used to identify etiological agent(s associated with this emerging disease, designated as grapevine redleaf disease (GRD. High quality RNA extracted from leaves of grape cultivars Merlot and Cabernet Franc with and without GRD symptoms was used to prepare cDNA libraries. Assembly of highly informative sequence reads generated from Illumina sequencing of cDNA libraries, followed by bioinformatic analyses of sequence contigs resulted in specific identification of taxonomically disparate viruses and viroids in samples with and without GRD symptoms. A single-stranded DNA virus, tentatively named Grapevine redleaf-associated virus (GRLaV, and Grapevine fanleaf virus were detected only in grapevines showing GRD symptoms. In contrast, Grapevine rupestris stem pitting-associated virus, Hop stunt viroid, Grapevine yellow speckle viroid 1, Citrus exocortis viroid and Citrus exocortis Yucatan viroid were present in both symptomatic and non-symptomatic grapevines. GRLaV was transmitted by the Virginia creeper leafhopper (Erythroneura ziczac Walsh from grapevine-to-grapevine under greenhouse conditions. Molecular and phylogenetic analyses indicated that GRLaV, almost identical to recently reported Grapevine Cabernet Franc-associated virus from New York and Grapevine red blotch-associated virus from California, represents an evolutionarily distinct lineage in the family Geminiviridae with genome characteristics distinct from other leafhopper-transmitted geminiviruses. GRD significantly reduced fruit yield and affected berry quality parameters demonstrating negative impacts of the disease. Higher quantities of carbohydrates were present in symptomatic leaves suggesting their possible role in the expression of redleaf symptoms.

  18. A leafhopper-transmissible DNA virus with novel evolutionary lineage in the family geminiviridae implicated in grapevine redleaf disease by next-generation sequencing.

    Science.gov (United States)

    Poojari, Sudarsana; Alabi, Olufemi J; Fofanov, Viacheslav Y; Naidu, Rayapati A

    2013-01-01

    A graft-transmissible disease displaying red veins, red blotches and total reddening of leaves in red-berried wine grape (Vitis vinifera L.) cultivars was observed in commercial vineyards. Next-generation sequencing technology was used to identify etiological agent(s) associated with this emerging disease, designated as grapevine redleaf disease (GRD). High quality RNA extracted from leaves of grape cultivars Merlot and Cabernet Franc with and without GRD symptoms was used to prepare cDNA libraries. Assembly of highly informative sequence reads generated from Illumina sequencing of cDNA libraries, followed by bioinformatic analyses of sequence contigs resulted in specific identification of taxonomically disparate viruses and viroids in samples with and without GRD symptoms. A single-stranded DNA virus, tentatively named Grapevine redleaf-associated virus (GRLaV), and Grapevine fanleaf virus were detected only in grapevines showing GRD symptoms. In contrast, Grapevine rupestris stem pitting-associated virus, Hop stunt viroid, Grapevine yellow speckle viroid 1, Citrus exocortis viroid and Citrus exocortis Yucatan viroid were present in both symptomatic and non-symptomatic grapevines. GRLaV was transmitted by the Virginia creeper leafhopper (Erythroneura ziczac Walsh) from grapevine-to-grapevine under greenhouse conditions. Molecular and phylogenetic analyses indicated that GRLaV, almost identical to recently reported Grapevine Cabernet Franc-associated virus from New York and Grapevine red blotch-associated virus from California, represents an evolutionarily distinct lineage in the family Geminiviridae with genome characteristics distinct from other leafhopper-transmitted geminiviruses. GRD significantly reduced fruit yield and affected berry quality parameters demonstrating negative impacts of the disease. Higher quantities of carbohydrates were present in symptomatic leaves suggesting their possible role in the expression of redleaf symptoms.

  19. TCTP is a critical factor in shrimp immune response to virus infection.

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    Wenlin Wu

    Full Text Available The translationally controlled tumor protein (TCTP is an abundant, ubiquitous, and conserved protein which plays important roles in a number of biological processes. In the present study, the TCTP in shrimp Litopenaeus vannamei was analyzed. The TCTP of L.vannamei, a 168-amino-acid polypeptide, shares a high degree of similarity with TCTPs from other species, having two TCTP protein signatures at the 45-55 aa and 123-145 aa motif. The mRNA and protein levels from different tissues were detected with the highest in muscle and the lowest in heart among all examined tissues. In addition, temporal TCTP expression was significantly up-regulated at 16 h and 48 h following infection with white spot syndrome virus (WSSV. Lastly, silencing of TCTP with dsRNA led to a significant increase of WSSV loads. These results provide new insights into the importance of TCTP as an evolutionarily conserved molecule for shrimp innate immunity against virus infection.

  20. Evolutionarily conserved cytogenetic changes in hematological malignancies of dogs and humans--man and his best friend share more than companionship.

    Science.gov (United States)

    Breen, Matthew; Modiano, Jaime F

    2008-01-01

    The pathophysiological similarities shared by many forms of human and canine disease, combined with the sophisticated genomic resources now available for the dog, have placed 'man's best friend' in a position of high visibility as a model system for a variety of biomedical concerns, including cancer. The importance of nonrandom cytogenetic abnormalities in human leukemia and lymphoma was recognized over 40 years ago, but the mechanisms of genome reorganization remain incompletely understood. The development of molecular cytogenetics, using fluorescence in situ hybridization (FISH) technology, has played a significant role in our understanding of cancer biology by providing a means for 'interrogating' tumor cells for a variety of gross genetic changes in the form of either numerical or structural chromosome aberrations. Here, we have identified cytogenetic abnormalities in naturally occurring canine hematopoietic tumors that are evolutionarily conserved compared with those that are considered characteristic of the corresponding human condition. These data suggest that humans and dogs share an ancestrally retained pathogenetic basis for cancer and that cytogenetic evaluation of canine tumors may provide greater insight into the biology of tumorigenesis.

  1. Significant reduction in notification and seroprevalence rates of hepatitis B virus infection among the population of Zhejiang Province, China, aged between 1 and 29years from 2006 to 2014.

    Science.gov (United States)

    Zhou, Yang; He, Hanqing; Deng, Xuan; Yan, Rui; Tang, Xuewen; Xie, Shuyun; Yao, Jun

    2017-08-03

    The Chinese government integrated hepatitis B vaccination into the national immunization program in 1992, when the hepatitis B birth dose was introduced in China. Zhejiang province is a relatively developed area in eastern China and was an area with high endemicity for hepatitis B virus (HBV) infection via mother-to-child transmission. The hepatitis B vaccine vaccination rates for the birth dose and 3- dose schedule in Zhejiang Province since 1992 have both remained above 90% [1]. The results of two hepatitis B seroepidemiological surveys conducted in 2006 and 2014, respectively, to evaluate the rates of notification and seroprevalence of HBV infection among the population of Zhejiang Province, China, aged between 1 and 29years. Data on the notification rates of HBV infection in Zhejiang province from 2006 to 2014 were obtained from the National Notifiable Disease Reporting System (NNDRS). The prevalence rate of HBV serological markers and the rate of immunization coverage were compared between surveys. The reported notification rates in people aged between 1 and 29years according to the NNDRS decreased approximately 4.88 times from 2006 to 2014. The prevalence of HBsAg decreased from 2.16% in 2006 to 1.05% in 2014, while the prevalence of anti-HBc decreased from 7.13% to 5.49%. The anti-HBc seroprevalence in the 15-29-year-old age group was significantly higher than that in all the other age groups both in the 2006 and 2014 serosurveys. The rate of anti-HBs seroprevalence in those aged between 1 and 14years was maintained at a high level between 2006 and 2014. The rate of hepatitis B reported and the rate of HBsAg positivity decreased significantly in Zhejiang province by maintaining the high-level coverage rate of the hepatitis B timely birth dose and three-dose schedule. While additional efforts are needed to achieve the goal of elimination. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Changing blood donor screening criteria from permanent deferral for men who have sex with men to individual sexual risk assessment: no evidence of a significant impact on the human immunodeficiency virus epidemic in Italy.

    Science.gov (United States)

    Suligoi, Barbara; Pupella, Simonetta; Regine, Vincenza; Raimondo, Mariangela; Velati, Claudio; Grazzini, Giuliano

    2013-07-01

    In 2001, the criteria for blood donor eligibility in Italy were modified by a ministerial decree from a permanent deferral for "men who have sex with men" to an individual risk assessment of sexual behaviours. The aim of this study was to evaluate the impact of this change in donor screening criteria on the human immunodeficiency virus epidemic among blood donors in Italy. We used the data obtained from the Italian blood donor epidemiological surveillance system. We compared data collected in 2009 and 2010, when the individual risk assessment policy was applied, with data collected in 1999 when permanent deferral was applied for men who have sex with men based on a declaration of sexual orientation. We evaluated the change over time in the relative proportion of HIV antibody-positive donors who likely acquired the infection from men who have sex with men vs heterosexual sexual exposure; the relative risk was calculated using 1999 as the reference year. In all 3 years, the majority of HIV antibody-positive donors reported sexual exposure as a risk factor for HIV infection; this proportion increased over time, although not statistically significantly. Heterosexuals always accounted for at least 40% of all HIV antibody-positive cases. The rate of HIV antibody-positive donors increased similarly in men who have sex with men and heterosexuals; specifically, the rate of HIV antibody-positive cases per 100,000 donors was more than 2-fold higher among men who have sex with men in 2009-2010 than in 1999 (2009-2010 vs 1999, RR =2.8; P =0.06), and that among heterosexuals was 1.5 fold higher (P =0.18). When comparing the period before (1999) and after (2009-2010), the implementation of the individual risk assessment policy in 2001, no significant increase in the proportion of men who have sex with men compared to heterosexuals was observed among HIV antibody-positive blood donors, suggesting that the change in donor deferral policy did not lead to a disproportionate increase

  3. ER stress, autophagy, and RNA viruses

    Directory of Open Access Journals (Sweden)

    Jia-Rong eJheng

    2014-08-01

    Full Text Available Endoplasmic reticulum (ER stress is a general term for representing the pathway by which various stimuli affect ER functions. ER stress induces the evolutionarily conserved signaling pathways, called the unfolded protein response (UPR, which compromises the stimulus and then determines whether the cell survives or dies. In recent years, ongoing research has suggested that these pathways may be linked to the autophagic response, which plays a key role in the cell’s response to various stressors. Autophagy performs a self-digestion function, and its activation protects cells against certain pathogens. However, the link between the UPR and autophagy may be more complicated. These two systems may act dependently, or the induction of one system may interfere with the other. Experimental studies have found that different viruses modulate these mechanisms to allow them to escape the host immune response or, worse, to exploit the host’s defense to their advantage; thus, this topic is a critical area in antiviral research. In this review, we summarize the current knowledge about how RNA viruses, including influenza virus, poliovirus, coxsackievirus, enterovirus 71, Japanese encephalitis virus, hepatitis C virus, and dengue virus, regulate these processes. We also discuss recent discoveries and how these will produce novel strategies for antiviral treatment.

  4. Evolutionarily conserved transcription factor Apontic controls the G1/S progression by inducing cyclin e during eye development

    KAUST Repository

    Liu, Qingxin

    2014-06-16

    During Drosophila eye development, differentiation initiates in the posterior region of the eye disk and progresses anteriorly as a wave marked by the morphogenetic furrow (MF), which demarcates the boundary between anterior undifferentiated cells and posterior differentiated photoreceptors. However, the mechanism underlying the regulation of gene expression immediately before the onset of differentiation remains unclear. Here, we show that Apontic (Apt), which is an evolutionarily conserved transcription factor, is expressed in the differentiating cells posterior to the MF. Moreover, it directly induces the expression of cyclin E and is also required for the G1-to-S phase transition, which is known to be essential for the initiation of cell differentiation at the MF. These observations identify a pathway crucial for eye development, governed by a mechanism in which Cyclin E promotes the G1-to-S phase transition when regulated by Apt.

  5. The disequilibrium of nucleosomes distribution along chromosomes plays a functional and evolutionarily role in regulating gene expression

    KAUST Repository

    Cui, Peng

    2011-08-19

    To further understand the relationship between nucleosome-space occupancy (NO) and global transcriptional activity in mammals, we acquired a set of genome-wide nucleosome distribution and transcriptome data from the mouse cerebrum and testis based on ChIP (H3)-seq and RNA-seq, respectively. We identified a nearly consistent NO patterns among three mouse tissues-cerebrum, testis, and ESCs-and found, through clustering analysis for transcriptional activation, that the NO variations among chromosomes are closely associated with distinct expression levels between house-keeping (HK) genes and tissue-specific (TS) genes. Both TS and HK genes form clusters albeit the obvious majority. This feature implies that NO patterns, i.e. nucleosome binding and clustering, are coupled with gene clustering that may be functionally and evolutionarily conserved in regulating gene expression among different cell types. © 2011 Cui et al.

  6. Reiterated WG/GW motifs form functionally and evolutionarily conserved ARGONAUTE-binding platforms in RNAi-related components

    Science.gov (United States)

    El-Shami, Mahmoud; Pontier, Dominique; Lahmy, Sylvie; Braun, Laurence; Picart, Claire; Vega, Danielle; Hakimi, Mohamed-Ali; Jacobsen, Steven E.; Cooke, Richard; Lagrange, Thierry

    2007-01-01

    Two forms of RNA Polymerase IV (PolIVa/PolIVb) have been implicated in RNA-directed DNA methylation (RdDM) in Arabidopsis. Prevailing models imply a distinct function for PolIVb by association of Argonaute4 (AGO4) with the C-terminal domain (CTD) of its largest subunit NRPD1b. Here we show that the extended CTD of NRPD1b-type proteins exhibits conserved Argonaute-binding capacity through a WG/GW-rich region that functionally distinguishes Pol IVb from Pol IVa, and that is essential for RdDM. Site-specific mutagenesis and domain-swapping experiments between AtNRPD1b and the human protein GW182 demonstrated that reiterated WG/GW motifs form evolutionarily and functionally conserved Argonaute-binding platforms in RNA interference (RNAi)-related components. PMID:17938239

  7. The disequilibrium of nucleosomes distribution along chromosomes plays a functional and evolutionarily role in regulating gene expression.

    Directory of Open Access Journals (Sweden)

    Peng Cui

    Full Text Available To further understand the relationship between nucleosome-space occupancy (NO and global transcriptional activity in mammals, we acquired a set of genome-wide nucleosome distribution and transcriptome data from the mouse cerebrum and testis based on ChIP (H3-seq and RNA-seq, respectively. We identified a nearly consistent NO patterns among three mouse tissues--cerebrum, testis, and ESCs--and found, through clustering analysis for transcriptional activation, that the NO variations among chromosomes are closely associated with distinct expression levels between house-keeping (HK genes and tissue-specific (TS genes. Both TS and HK genes form clusters albeit the obvious majority. This feature implies that NO patterns, i.e. nucleosome binding and clustering, are coupled with gene clustering that may be functionally and evolutionarily conserved in regulating gene expression among different cell types.

  8. Evolutionarily conserved bias of amino-acid usage refines the definition of PDZ-binding motif

    Directory of Open Access Journals (Sweden)

    Launey Thomas

    2011-06-01

    Full Text Available Abstract Background The interactions between PDZ (PSD-95, Dlg, ZO-1 domains and PDZ-binding motifs play central roles in signal transductions within cells. Proteins with PDZ domains bind to PDZ-binding motifs almost exclusively when the motifs are located at the carboxyl (C- terminal ends of their binding partners. However, it remains little explored whether PDZ-binding motifs show any preferential location at the C-terminal ends of proteins, at genome-level. Results Here, we examined the distribution of the type-I (x-x-S/T-x-I/L/V or type-II (x-x-V-x-I/V PDZ-binding motifs in proteins encoded in the genomes of five different species (human, mouse, zebrafish, fruit fly and nematode. We first established that these PDZ-binding motifs are indeed preferentially present at their C-terminal ends. Moreover, we found specific amino acid (AA bias for the 'x' positions in the motifs at the C-terminal ends. In general, hydrophilic AAs were favored. Our genomics-based findings confirm and largely extend the results of previous interaction-based studies, allowing us to propose refined consensus sequences for all of the examined PDZ-binding motifs. An ontological analysis revealed that the refined motifs are functionally relevant since a large fraction of the proteins bearing the motif appear to be involved in signal transduction. Furthermore, co-precipitation experiments confirmed two new protein interactions predicted by our genomics-based approach. Finally, we show that influenza virus pathogenicity can be correlated with PDZ-binding motif, with high-virulence viral proteins bearing a refined PDZ-binding motif. Conclusions Our refined definition of PDZ-binding motifs should provide important clues for identifying functional PDZ-binding motifs and proteins involved in signal transduction.

  9. ECHO virus

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/001340.htm ECHO virus To use the sharing features on this page, please enable JavaScript. Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that can lead ...

  10. Clonality and intracellular polyploidy in virus evolution and pathogenesis

    Science.gov (United States)

    Perales, Celia; Moreno, Elena; Domingo, Esteban

    2015-01-01

    In the present article we examine clonality in virus evolution. Most viruses retain an active recombination machinery as a potential means to initiate new levels of genetic exploration that go beyond those attainable solely by point mutations. However, despite abundant recombination that may be linked to molecular events essential for genome replication, herein we provide evidence that generation of recombinants with altered biological properties is not essential for the completion of the replication cycles of viruses, and that viral lineages (near-clades) can be defined. We distinguish mechanistically active but inconsequential recombination from evolutionarily relevant recombination, illustrated by episodes in the field and during experimental evolution. In the field, recombination has been at the origin of new viral pathogens, and has conferred fitness advantages to some viruses once the parental viruses have attained a sufficient degree of diversification by point mutations. In the laboratory, recombination mediated a salient genome segmentation of foot-and-mouth disease virus, an important animal pathogen whose genome in nature has always been characterized as unsegmented. We propose a model of continuous mutation and recombination, with punctuated, biologically relevant recombination events for the survival of viruses, both as disease agents and as promoters of cellular evolution. Thus, clonality is the standard evolutionary mode for viruses because recombination is largely inconsequential, since the decisive events for virus replication and survival are not dependent on the exchange of genetic material and formation of recombinant (mosaic) genomes. PMID:26195777

  11. IAPs contain an evolutionarily conserved ubiquitin-binding domain that regulates NF-kappaB as well as cell survival and oncogenesis

    DEFF Research Database (Denmark)

    Gyrd-Hansen, Mads; Darding, Maurice; Miasari, Maria

    2008-01-01

    in cancer and their expression level is implicated in contributing to tumorigenesis, chemoresistance, disease progression and poor patient-survival. Here, we have identified an evolutionarily conserved ubiquitin-associated (UBA) domain in IAPs, which enables them to bind to Lys 63-linked polyubiquitin. We...

  12. Evolutionary ecology of virus emergence.

    Science.gov (United States)

    Dennehy, John J

    2017-02-01

    The cross-species transmission of viruses into new host populations, termed virus emergence, is a significant issue in public health, agriculture, wildlife management, and related fields. Virus emergence requires overlap between host populations, alterations in virus genetics to permit infection of new hosts, and adaptation to novel hosts such that between-host transmission is sustainable, all of which are the purview of the fields of ecology and evolution. A firm understanding of the ecology of viruses and how they evolve is required for understanding how and why viruses emerge. In this paper, I address the evolutionary mechanisms of virus emergence and how they relate to virus ecology. I argue that, while virus acquisition of the ability to infect new hosts is not difficult, limited evolutionary trajectories to sustained virus between-host transmission and the combined effects of mutational meltdown, bottlenecking, demographic stochasticity, density dependence, and genetic erosion in ecological sinks limit most emergence events to dead-end spillover infections. Despite the relative rarity of pandemic emerging viruses, the potential of viruses to search evolutionary space and find means to spread epidemically and the consequences of pandemic viruses that do emerge necessitate sustained attention to virus research, surveillance, prophylaxis, and treatment. © 2016 New York Academy of Sciences.

  13. Cloning of an Avian Adeno-Associated Virus (AAAV) and Generation of Recombinant AAAV Particles

    OpenAIRE

    Bossis, Ioannis; Chiorini, John A.

    2003-01-01

    Recent studies have proposed that adeno-associated viruses (AAVs) are not evolutionarily linked to other mammalian autonomous parvoviruses but are more closely linked to the autonomous parvoviruses of birds. To better understand the relationship between primate and avian AAVs (AAAVs), we cloned and sequenced the genome of an AAAV (ATCC VR-865) and generated recombinant AAAV particles. The genome of AAAV is 4,694 nucleotides in length and has organization similar to that of other AAVs. The ent...

  14. An evolutionarily conserved arginine is essential for Tre1 G protein-coupled receptor function during germ cell migration in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Angela R Kamps

    Full Text Available BACKGROUND: G protein-coupled receptors (GPCRs play central roles in mediating cellular responses to environmental signals leading to changes in cell physiology and behaviors, including cell migration. Numerous clinical pathologies including metastasis, an invasive form of cell migration, have been linked to abnormal GPCR signaling. While the structures of some GPCRs have been defined, the in vivo roles of conserved amino acid residues and their relationships to receptor function are not fully understood. Trapped in endoderm 1 (Tre1 is an orphan receptor of the rhodopsin class that is necessary for primordial germ cell migration in Drosophila melanogaster embryos. In this study, we employ molecular genetic approaches to identify residues in Tre1 that are critical to its functions in germ cell migration. METHODOLOGY/PRINCIPAL FINDINGS: First, we show that the previously reported scattershot mutation is an allele of tre1. The scattershot allele results in an in-frame deletion of 8 amino acids at the junction of the third transmembrane domain and the second intracellular loop of Tre1 that dramatically impairs the function of this GPCR in germ cell migration. To further refine the molecular basis for this phenotype, we assayed the effects of single amino acid substitutions in transgenic animals and determined that the arginine within the evolutionarily conserved E/N/DRY motif is critical for receptor function in mediating germ cell migration within an intact developing embryo. CONCLUSIONS/SIGNIFICANCE: These structure-function studies of GPCR signaling in native contexts will inform future studies into the basic biology of this large and clinically important family of receptors.

  15. Deep sequencing of organ- and stage-specific microRNAs in the evolutionarily basal insect Blattella germanica (L. (Dictyoptera, Blattellidae.

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    Alexandre S Cristino

    Full Text Available BACKGROUND: microRNAs (miRNAs have been reported as key regulators at post-transcriptional level in eukaryotic cells. In insects, most of the studies have focused in holometabolans while only recently two hemimetabolans (Locusta migratoria and Acyrthosiphon pisum have had their miRNAs identified. Therefore, the study of the miRNAs of the evolutionarily basal hemimetabolan Blattella germanica may provide valuable insights on the structural and functional evolution of miRNAs. METHODOLOGY/PRINCIPAL FINDINGS: Small RNA libraries of the cockroach B. germanica were built from the whole body of the last instar nymph, and the adult ovaries. The high throughput Solexa sequencing resulted in approximately 11 and 8 million reads for the whole-body and ovaries, respectively. Bioinformatic analyses identified 38 known miRNAs as well as 11 known miRNA*s. We also found 70 miRNA candidates conserved in other insects and 170 candidates specific to B. germanica. The positive correlation between Solexa data and real-time quantitative PCR showed that number of reads can be used as a quantitative approach. Five novel miRNA precursors were identified and validated by PCR and sequencing. Known miRNAs and novel candidates were also validated by decreasing levels of their expression in dicer-1 RNAi knockdown individuals. The comparison of the two libraries indicates that whole-body nymph contain more known miRNAs than ovaries, whereas the adult ovaries are enriched with novel miRNA candidates. CONCLUSIONS/SIGNIFICANCE: Our study has identified many known miRNAs and novel miRNA candidates in the basal hemimetabolan insect B. germanica, and most of the specific sequences were found in ovaries. Deep sequencing data reflect miRNA abundance and dicer-1 RNAi assay is shown to be a reliable method for validation of novel miRNAs.

  16. Post-transcriptional exon shuffling events in humans can be evolutionarily conserved and abundant

    OpenAIRE

    Al-Balool, Haya H.; Weber, David; Liu, Yilei; Wade, Mark; Guleria, Kamlesh; Nam, Pitsien Lang Ping; Clayton, Jake; Rowe, William; Coxhead, Jonathan; Irving, Julie; Elliott, David J.; Hall, Andrew G.; Santibanez-Koref, Mauro; Jackson, Michael S.

    2011-01-01

    In silico analyses have established that transcripts from some genes can be processed into RNAs with rearranged exon order relative to genomic structure (post-transcriptional exon shuffling, or PTES). Although known to contribute to transcriptome diversity in some species, to date the structure, distribution, abundance, and functional significance of human PTES transcripts remains largely unknown. Here, using high-throughput transcriptome sequencing, we identify 205 putative human PTES produc...

  17. Functional role of phenylacetic acid from metapleural gland secretions in controlling fungal pathogens in evolutionarily derived leaf-cutting ants

    Science.gov (United States)

    Fernández-Marín, Hermógenes; Nash, David R.; Higginbotham, Sarah; Estrada, Catalina; van Zweden, Jelle S.; d'Ettorre, Patrizia; Wcislo, William T.; Boomsma, Jacobus J.

    2015-01-01

    Fungus-farming ant colonies vary four to five orders of magnitude in size. They employ compounds from actinomycete bacteria and exocrine glands as antimicrobial agents. Atta colonies have millions of ants and are particularly relevant for understanding hygienic strategies as they have abandoned their ancestors' prime dependence on antibiotic-based biological control in favour of using metapleural gland (MG) chemical secretions. Atta MGs are unique in synthesizing large quantities of phenylacetic acid (PAA), a known but little investigated antimicrobial agent. We show that particularly the smallest workers greatly reduce germination rates of Escovopsis and Metarhizium spores after actively applying PAA to experimental infection targets in garden fragments and transferring the spores to the ants' infrabuccal cavities. In vitro assays further indicated that Escovopsis strains isolated from evolutionarily derived leaf-cutting ants are less sensitive to PAA than strains from phylogenetically more basal fungus-farming ants, consistent with the dynamics of an evolutionary arms race between virulence and control for Escovopsis, but not Metarhizium. Atta ants form larger colonies with more extreme caste differentiation relative to other attines, in societies characterized by an almost complete absence of reproductive conflicts. We hypothesize that these changes are associated with unique evolutionary innovations in chemical pest management that appear robust against selection pressure for resistance by specialized mycopathogens. PMID:25925100

  18. FAM20: an evolutionarily conserved family of secreted proteins expressed in hematopoietic cells

    Directory of Open Access Journals (Sweden)

    Cobos Everardo

    2005-01-01

    Full Text Available Abstract Background Hematopoiesis is a complex developmental process controlled by a large number of factors that regulate stem cell renewal, lineage commitment and differentiation. Secreted proteins, including the hematopoietic growth factors, play critical roles in these processes and have important biological and clinical significance. We have employed representational difference analysis to identify genes that are differentially expressed during experimentally induced myeloid differentiation in the murine EML hematopoietic stem cell line. Results One identified clone encoded a previously unidentified protein of 541 amino acids that contains an amino terminal signal sequence but no other characterized domains. This protein is a member of family of related proteins that has been named family with sequence similarity 20 (FAM20 with three members (FAM20A, FAM20B and FAM20C in mammals. Evolutionary comparisons revealed the existence of a single FAM20 gene in the simple vertebrate Ciona intestinalis and the invertebrate worm Caenorhabditis elegans and two genes in two insect species, Drosophila melanogaster and Anopheles gambiae. Six FAM20 family members were identified in the genome of the pufferfish, Fugu rubripes and five members in the zebrafish, Danio rerio. The mouse Fam20a protein was ectopically expressed in a mammalian cell line and found to be a bona fide secreted protein and efficient secretion was dependent on the integrity of the signal sequence. Expression analysis revealed that the Fam20a gene was indeed differentially expressed during hematopoietic differentiation and that the other two family members (Fam20b and Fam20c were also expressed during hematcpoiesis but that their mRNA levels did not vary significantly. Likewise FAM20A was expressed in more limited set of human tissues than the other two family members. Conclusions The FAM20 family represents a new family of secreted proteins with potential functions in regulating

  19. Influenza A and B Virus Intertypic Reassortment through Compatible Viral Packaging Signals

    Science.gov (United States)

    Baker, Steven F.; Nogales, Aitor; Finch, Courtney; Tuffy, Kevin M.; Domm, William; Perez, Daniel R.; Topham, David J.

    2014-01-01

    ABSTRACT Influenza A and B viruses cocirculate in humans and together cause disease and seasonal epidemics. These two types of influenza viruses are evolutionarily divergent, and exchange of genetic segments inside coinfected cells occurs frequently within types but never between influenza A and B viruses. Possible mechanisms inhibiting the intertypic reassortment of genetic segments could be due to incompatible protein functions of segment homologs, a lack of processing of heterotypic segments by influenza virus RNA-dependent RNA polymerase, an inhibitory effect of viral proteins on heterotypic virus function, or an inability to specifically incorporate heterotypic segments into budding virions. Here, we demonstrate that the full-length hemagglutinin (HA) of prototype influenza B viruses can complement the function of multiple influenza A viruses. We show that viral noncoding regions were sufficient to drive gene expression for either type A or B influenza virus with its cognate or heterotypic polymerase. The native influenza B virus HA segment could not be incorporated into influenza A virus virions. However, by adding the influenza A virus packaging signals to full-length influenza B virus glycoproteins, we rescued influenza A viruses that possessed HA, NA, or both HA and NA of influenza B virus. Furthermore, we show that, similar to single-cycle infectious influenza A virus, influenza B virus cannot incorporate heterotypic transgenes due to packaging signal incompatibilities. Altogether, these results demonstrate that the lack of influenza A and B virus reassortants can be attributed at least in part to incompatibilities in the virus-specific packaging signals required for effective segment incorporation into nascent virions. IMPORTANCE Reassortment of influenza A or B viruses provides an evolutionary strategy leading to unique genotypes, which can spawn influenza A viruses with pandemic potential. However, the mechanism preventing intertypic reassortment or

  20. Evolutionarily conserved sites in yeast tropomyosin function in cell polarity, transport and contractile ring formation

    Directory of Open Access Journals (Sweden)

    Susanne Cranz-Mileva

    2015-08-01

    Full Text Available Tropomyosin is a coiled-coil protein that binds and regulates actin filaments. The tropomyosin gene in Schizosaccharomyces pombe, cdc8, is required for formation of actin cables, contractile rings, and polar localization of actin patches. The roles of conserved residues were investigated in gene replacement mutants. The work validates an evolution-based approach to identify tropomyosin functions in living cells and sites of potential interactions with other proteins. A cdc8 mutant with near-normal actin affinity affects patch polarization and vacuole fusion, possibly by affecting Myo52p, a class V myosin, function. The presence of labile residual cell attachments suggests a delay in completion of cell division and redistribution of cell patches following cytokinesis. Another mutant with a mild phenotype is synthetic negative with GFP-fimbrin, inferring involvement of the mutated tropomyosin sites in interaction between the two proteins. Proteins that assemble in the contractile ring region before actin do so in a mutant cdc8 strain that cannot assemble condensed actin rings, yet some cells can divide. Of general significance, LifeAct-GFP negatively affects the actin cytoskeleton, indicating caution in its use as a biomarker for actin filaments.

  1. Computational Analysis of an Evolutionarily Conserved VertebrateMuscle Alternative Splicing Program

    Energy Technology Data Exchange (ETDEWEB)

    Das, Debopriya; Clark, Tyson A.; Schweitzer, Anthony; Marr,Henry; Yamamoto, Miki L.; Parra, Marilyn K.; Arribere, Josh; Minovitsky,Simon; Dubchak, Inna; Blume, John E.; Conboy, John G.

    2006-06-15

    A novel exon microarray format that probes gene expression with single exon resolution was employed to elucidate critical features of a vertebrate muscle alternative splicing program. A dataset of 56 microarray-defined, muscle-enriched exons and their flanking introns were examined computationally in order to investigate coordination of the muscle splicing program. Candidate intron regulatory motifs were required to meet several stringent criteria: significant over-representation near muscle-enriched exons, correlation with muscle expression, and phylogenetic conservation among genomes of several vertebrate orders. Three classes of regulatory motifs were identified in the proximal downstream intron, within 200nt of the target exons: UGCAUG, a specific binding site for Fox-1 related splicing factors; ACUAAC, a novel branchpoint-like element; and UG-/UGC-rich elements characteristic of binding sites for CELF splicing factors. UGCAUG was remarkably enriched, being present in nearly one-half of all cases. These studies suggest that Fox and CELF splicing factors play a major role in enforcing the muscle-specific alternative splicing program, facilitating expression of a set of unique isoforms of cytoskeletal proteins that are critical to muscle cell differentiation. Supplementary materials: There are four supplementary tables and one supplementary figure. The tables provide additional detailed information concerning the muscle-enriched datasets, and about over-represented oligonucleotide sequences in the flanking introns. The supplementary figure shows RT-PCR data confirming the muscle-enriched expression of exons predicted from the microarray analysis.

  2. Virus, Oncolytic Virus and Human Prostate Cancer.

    Science.gov (United States)

    Liu, Guang Bin; Zhao, Liang; Zhang, Lifang; Zhao, Kong-Nan

    2017-01-01

    Prostate cancer (PCa), a disease, is characterized by abnormal cell growth in the prostate - a gland in the male reproductive system. Although older age and a family history of the disease have been recognized as the risk factors of PCa, the cause of this cancer remains unclear. Currently, PCa is one of the leading causes of cancer death among men of all races. In this review study, we first discuss the controversy of the contribution of virus infection to PCa, and subsequently summarize the development of oncolytic virotherapy for PCa in the past several years. Mounting evidence suggests that infections with various viruses are causally linked to PCa pathogenesis. Published studies have provided strong evidence that at least two viruses (RXMV and HPV) contribute to prostate tumourigenicity and impact on the survival of patients with malignant PCa. Traditional therapies including chemotherapy and radiotherapy are unable to distinguish cancer cells from normal cells, which are a significant drawback and leads to toxicities for PCa patients undergoing treatment. So far, few other options are available for treating patients with advanced PCa. For PCa treatment, oncolytic virotherapy appears to be much more attractive, which uses live viruses to selectively kill cancer cells. Oncolytic viruses can be genetically engineered to induce cancer cell lysis through virus replication and expression of cytotoxic proteins. Virotherapy is being developed to be a novel therapy for cancers, which uses oncotropic and oncolytic viruses with their abilities to find and destroy malignant cells in the body. As oncolytic viruses are a relatively new class of anti-cancer immunotherapy agents, several important barriers still exist on the road to the use of oncolytic viruses for PCa therapy. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Post-transcriptional exon shuffling events in humans can be evolutionarily conserved and abundant.

    Science.gov (United States)

    Al-Balool, Haya H; Weber, David; Liu, Yilei; Wade, Mark; Guleria, Kamlesh; Nam, Pitsien Lang Ping; Clayton, Jake; Rowe, William; Coxhead, Jonathan; Irving, Julie; Elliott, David J; Hall, Andrew G; Santibanez-Koref, Mauro; Jackson, Michael S

    2011-11-01

    In silico analyses have established that transcripts from some genes can be processed into RNAs with rearranged exon order relative to genomic structure (post-transcriptional exon shuffling, or PTES). Although known to contribute to transcriptome diversity in some species, to date the structure, distribution, abundance, and functional significance of human PTES transcripts remains largely unknown. Here, using high-throughput transcriptome sequencing, we identify 205 putative human PTES products from 176 genes. We validate 72 out of 112 products analyzed using RT-PCR, and identify additional PTES products structurally related to 61% of validated targets. Sequencing of these additional products reveals GT-AG dinucleotides at >95% of the splice junctions, confirming that they are processed by the spliceosome. We show that most PTES transcripts are expressed in a wide variety of human tissues, that they can be polyadenylated, and that some are conserved in mouse. We also show that they can extend into 5' and 3' UTRs, consistent with formation via trans-splicing of independent pre-mRNA molecules. Finally, we use real-time PCR to compare the abundance of PTES exon junctions relative to canonical exon junctions within the transcripts from seven genes. PTES exon junctions are present at 90% of the levels of canonical junctions, with transcripts from MAN1A2, PHC3, TLE4, and CDK13 exhibiting the highest levels. This is the first systematic experimental analysis of PTES in human, and it suggests both that the phenomenon is much more widespread than previously thought and that some PTES transcripts could be functional.

  4. Evolutionarily conserved mammalian adenine nucleotide translocase 4 is essential for spermatogenesis.

    Science.gov (United States)

    Brower, Jeffrey V; Rodic, Nemanja; Seki, Tsugio; Jorgensen, Marda; Fliess, Naime; Yachnis, Anthony T; McCarrey, John R; Oh, S Paul; Terada, Naohiro

    2007-10-05

    The adenine nucleotide translocases (Ant) facilitate the transport of ADP and ATP by an antiport mechanism across the inner mitochondrial membrane, thus playing an essential role in cellular energy metabolism. We recently identified a novel member of the Ant family in mouse, Ant4, of which gene configuration as well as amino acid homology is well conserved among mammals. The conservation of Ant4 in mammals, along with the absence of Ant4 in nonmammalian species, suggests a unique and indispensable role for this ADP/ATP carrier in mammalian development. Of interest, in contrast to its paralog Ant2, which is encoded by the X chromosome and ubiquitously expressed in somatic cells, Ant4 is encoded by an autosome and selectively expressed in testicular germ cells. Immunohistochemical examination as well as RNA expression analysis using separated spermatogenic cell types revealed that Ant4 expression was particularly high in spermatocytes. When we generated Ant4-deficient mice by targeted disruption, a significant reduction in testicular size was observed without any other distinguishable abnormalities in the mice. Histological examination as well as stage-specific gene expression analysis in adult and neonatal testes revealed a severe reduction of spermatocytes accompanied by increased apoptosis. Subsequently, the Ant4-deficient male mice were infertile. Taken together, these data elucidated the indispensable role of Ant4 in murine spermatogenesis. Considering the unique conservation and chromosomal location of the Ant family genes in mammals, the Ant4 gene may have arisen in mammalian ancestors and been conserved in mammals to serve as the sole and essential mitochondrial ADP/ATP carrier during spermatogenesis where the sex chromosome-linked Ant2 gene is inactivated.

  5. Drosophila Ncd reveals an evolutionarily conserved powerstroke mechanism for homodimeric and heterodimeric kinesin-14s.

    Science.gov (United States)

    Zhang, Pengwei; Dai, Wei; Hahn, Juergen; Gilbert, Susan P

    2015-05-19

    Drosophila melanogaster kinesin-14 Ncd cross-links parallel microtubules at the spindle poles and antiparallel microtubules within the spindle midzone to play roles in bipolar spindle assembly and proper chromosome distribution. As observed for Saccharomyces cerevisiae kinesin-14 Kar3Vik1 and Kar3Cik1, Ncd binds adjacent microtubule protofilaments in a novel microtubule binding configuration and uses an ATP-promoted powerstroke mechanism. The hypothesis tested here is that Kar3Vik1 and Kar3Cik1, as well as Ncd, use a common ATPase mechanism for force generation even though the microtubule interactions for both Ncd heads are modulated by nucleotide state. The presteady-state kinetics and computational modeling establish an ATPase mechanism for a powerstroke model of Ncd that is very similar to those determined for Kar3Vik1 and Kar3Cik1, although these heterodimers have one Kar3 catalytic motor domain and a Vik1/Cik1 partner motor homology domain whose interactions with microtubules are not modulated by nucleotide state but by strain. The results indicate that both Ncd motor heads bind the microtubule lattice; two ATP binding and hydrolysis events are required for each powerstroke; and a slow step occurs after microtubule collision and before the ATP-promoted powerstroke. Note that unlike conventional myosin-II or other processive molecular motors, Ncd requires two ATP turnovers rather than one for a single powerstroke-driven displacement or step. These results are significant because all metazoan kinesin-14s are homodimers, and the results presented show that despite their structural and functional differences, the heterodimeric and homodimeric kinesin-14s share a common evolutionary structural and mechanochemical mechanism for force generation.

  6. Chikungunya virus

    Science.gov (United States)

    Chikungunya virus infection; Chikungunya ... Where Chikungunya is Found Before 2013, the virus was found in Africa, Asia, Europe, and the Indian and Pacific oceans. In late 2013, outbreaks occurred for the first time in the ...

  7. Zika Virus

    Science.gov (United States)

    ... through blood transfusions. There have been outbreaks of Zika virus in the United States, Africa, Southeast Asia, the ... not travel to areas where there is a Zika virus outbreak. If you do decide to travel, first ...

  8. Chikungunya Virus

    Science.gov (United States)

    ... Gaines, PhD, MPH, MA, CHES Differentiating Chikungunya From Dengue: A Clinical Challenge For Travelers CDC Travelers' Health Chikungunya Virus Home Prevention Transmission Symptoms & Treatment Geographic Distribution Chikungunya virus in the United States ...

  9. Zika Virus

    Science.gov (United States)

    ... Funding CDC Activities For Healthcare Providers Clinical Evaluation & Disease Sexual Transmission HIV Infection & Zika Virus Testing for Zika Test Specimens – At Time of Birth Diagnostic Tests Understanding Zika Virus Test Results ...

  10. Evolutionary dynamics of Newcastle disease virus

    Science.gov (United States)

    Miller, P.J.; Kim, L.M.; Ip, Hon S.; Afonso, C.L.

    2009-01-01

    A comprehensive dataset of NDV genome sequences was evaluated using bioinformatics to characterize the evolutionary forces affecting NDV genomes. Despite evidence of recombination in most genes, only one event in the fusion gene of genotype V viruses produced evolutionarily viable progenies. The codon-associated rate of change for the six NDV proteins revealed that the highest rate of change occurred at the fusion protein. All proteins were under strong purifying (negative) selection; the fusion protein displayed the highest number of amino acids under positive selection. Regardless of the phylogenetic grouping or the level of virulence, the cleavage site motif was highly conserved implying that mutations at this site that result in changes of virulence may not be favored. The coding sequence of the fusion gene and the genomes of viruses from wild birds displayed higher yearly rates of change in virulent viruses than in viruses of low virulence, suggesting that an increase in virulence may accelerate the rate of NDV evolution. ?? 2009 Elsevier Inc.

  11. Evolutionarily divergent spliceosomal snRNAs and a conserved non-coding RNA processing motif in Giardia lamblia

    Science.gov (United States)

    Hudson, Andrew J.; Moore, Ashley N.; Elniski, David; Joseph, Joella; Yee, Janet; Russell, Anthony G.

    2012-01-01

    Non-coding RNAs (ncRNAs) have diverse essential biological functions in all organisms, and in eukaryotes, two such classes of ncRNAs are the small nucleolar (sno) and small nuclear (sn) RNAs. In this study, we have identified and characterized a collection of sno and snRNAs in Giardia lamblia, by exploiting our discovery of a conserved 12 nt RNA processing sequence motif found in the 3′ end regions of a large number of G. lamblia ncRNA genes. RNA end mapping and other experiments indicate the motif serves to mediate ncRNA 3′ end formation from mono- and di-cistronic RNA precursor transcripts. Remarkably, we find the motif is also utilized in the processing pathway of all four previously identified trans-spliced G. lamblia introns, revealing a common RNA processing pathway for ncRNAs and trans-spliced introns in this organism. Motif sequence conservation then allowed for the bioinformatic and experimental identification of additional G. lamblia ncRNAs, including new U1 and U6 spliceosomal snRNA candidates. The U6 snRNA candidate was then used as a tool to identity novel U2 and U4 snRNAs, based on predicted phylogenetically conserved snRNA–snRNA base-pairing interactions, from a set of previously identified G. lamblia ncRNAs without assigned function. The Giardia snRNAs retain the core features of spliceosomal snRNAs but are sufficiently evolutionarily divergent to explain the difficulties in their identification. Most intriguingly, all of these snRNAs show structural features diagnostic of U2-dependent/major and U12-dependent/minor spliceosomal snRNAs. PMID:23019220

  12. H3K23me1 is an evolutionarily conserved histone modification associated with CG DNA methylation in Arabidopsis.

    Science.gov (United States)

    Trejo-Arellano, Minerva S; Mahrez, Walid; Nakamura, Miyuki; Moreno-Romero, Jordi; Nanni, Paolo; Köhler, Claudia; Hennig, Lars

    2017-04-01

    Amino-terminal tails of histones are targets for diverse post-translational modifications whose combinatorial action may constitute a code that will be read and interpreted by cellular proteins to define particular transcriptional states. Here, we describe monomethylation of histone H3 lysine 23 (H3K23me1) as a histone modification not previously described in plants. H3K23me1 is an evolutionarily conserved mark in diverse species of flowering plants. Chromatin immunoprecipitation followed by high-throughput sequencing in Arabidopsis thaliana showed that H3K23me1 was highly enriched in pericentromeric regions and depleted from chromosome arms. In transposable elements it co-localized with CG, CHG and CHH DNA methylation as well as with the heterochromatic histone mark H3K9me2. Transposable elements are often rich in H3K23me1 but different families vary in their enrichment: LTR-Gypsy elements are most enriched and RC/Helitron elements are least enriched. The histone methyltransferase KRYPTONITE and normal DNA methylation were required for normal levels of H3K23me1 on transposable elements. Immunostaining experiments confirmed the pericentromeric localization and also showed mild enrichment in less condensed regions. Accordingly, gene bodies of protein-coding genes had intermediate H3K23me1 levels, which coexisted with CG DNA methylation. Enrichment of H3K23me1 along gene bodies did not correlate with transcription levels. Together, this work establishes H3K23me1 as a so far undescribed component of the plant histone code. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  13. Comparative analysis of evolutionarily conserved motifs of epidermal growth factor receptor 2 (HER2 predicts novel potential therapeutic epitopes.

    Directory of Open Access Journals (Sweden)

    Xiaohong Deng

    Full Text Available Overexpression of human epidermal growth factor receptor 2 (HER2 is associated with tumor aggressiveness and poor prognosis in breast cancer. With the availability of therapeutic antibodies against HER2, great strides have been made in the clinical management of HER2 overexpressing breast cancer. However, de novo and acquired resistance to these antibodies presents a serious limitation to successful HER2 targeting treatment. The identification of novel epitopes of HER2 that can be used for functional/region-specific blockade could represent a central step in the development of new clinically relevant anti-HER2 antibodies. In the present study, we present a novel computational approach as an auxiliary tool for identification of novel HER2 epitopes. We hypothesized that the structurally and linearly evolutionarily conserved motifs of the extracellular domain of HER2 (ECD HER2 contain potential druggable epitopes/targets. We employed the PROSITE Scan to detect structurally conserved motifs and PRINTS to search for linearly conserved motifs of ECD HER2. We found that the epitopes recognized by trastuzumab and pertuzumab are located in the predicted conserved motifs of ECD HER2, supporting our initial hypothesis. Considering that structurally and linearly conserved motifs can provide functional specific configurations, we propose that by comparing the two types of conserved motifs, additional druggable epitopes/targets in the ECD HER2 protein can be identified, which can be further modified for potential therapeutic application. Thus, this novel computational process for predicting or searching for potential epitopes or key target sites may contribute to epitope-based vaccine and function-selected drug design, especially when x-ray crystal structure protein data is not available.

  14. Comparative analysis of evolutionarily conserved motifs of epidermal growth factor receptor 2 (HER2) predicts novel potential therapeutic epitopes.

    Science.gov (United States)

    Deng, Xiaohong; Zheng, Xuxu; Yang, Huanming; Moreira, José Manuel Afonso; Brünner, Nils; Christensen, Henrik

    2014-01-01

    Overexpression of human epidermal growth factor receptor 2 (HER2) is associated with tumor aggressiveness and poor prognosis in breast cancer. With the availability of therapeutic antibodies against HER2, great strides have been made in the clinical management of HER2 overexpressing breast cancer. However, de novo and acquired resistance to these antibodies presents a serious limitation to successful HER2 targeting treatment. The identification of novel epitopes of HER2 that can be used for functional/region-specific blockade could represent a central step in the development of new clinically relevant anti-HER2 antibodies. In the present study, we present a novel computational approach as an auxiliary tool for identification of novel HER2 epitopes. We hypothesized that the structurally and linearly evolutionarily conserved motifs of the extracellular domain of HER2 (ECD HER2) contain potential druggable epitopes/targets. We employed the PROSITE Scan to detect structurally conserved motifs and PRINTS to search for linearly conserved motifs of ECD HER2. We found that the epitopes recognized by trastuzumab and pertuzumab are located in the predicted conserved motifs of ECD HER2, supporting our initial hypothesis. Considering that structurally and linearly conserved motifs can provide functional specific configurations, we propose that by comparing the two types of conserved motifs, additional druggable epitopes/targets in the ECD HER2 protein can be identified, which can be further modified for potential therapeutic application. Thus, this novel computational process for predicting or searching for potential epitopes or key target sites may contribute to epitope-based vaccine and function-selected drug design, especially when x-ray crystal structure protein data is not available.

  15. Is altruism evolutionarily stable ?

    NARCIS (Netherlands)

    Bester, H.; Güth, W.

    1994-01-01

    We develop an evolutionary approach to explain altruistic preferences. Given their preferences, individuals interact rationally with each other. By comparing the success of players with different preferences, we investigate whether evolution favors altruistic or selfish attitudes. The outcome

  16. Thrips-transmitted Viruses Infect a Number of Florida Crops

    Science.gov (United States)

    The ilarviruses Tomato necrotic streak virus and Tobacco streak virus are present in south Florida. Both species cause economically significant disease in vegetable crop. Control of these viruses makes use of integrated pest management approaches....

  17. Evolutionarily stable strategy of carbon and nitrogen investments in forest leaves and its application in vegetation dynamic modeling

    Science.gov (United States)

    Weng, E.; Farrior, C.; Dybzinski, R.; Pacala, S. W.

    2015-12-01

    Leaf mass per area (LMA) and leaf lifespan (LL) are two highly correlated plant traits that are key to plant physiological and ecological properties. Usually, low LMA means short LL, high nitrogen (N) content per unit mass, and fast turnover rates of nutrients; high LMA leads to long LL, low N content, and slow turnover rates. Deciduous trees with low LMA and short lifespan leaves have low carbon cost but high nitrogen demand; and evergreen trees, with high LMA and long lifespan leaves, have high carbon cost but low nitrogen demand. These relationships lead to: 1) evergreen trees have higher leaf area index than deciduous trees; 2) evergreen trees' carbon use efficiency is lower than the deciduous trees' because of their thick leaves and therefore high maintenance respiration; 3) the advantage of evergreens trees brought by their extra leaves over deciduous trees diminishes with increase N in ecosystem. These facts determine who will win when trees compete with each other in a N-limited ecosystem. In this study, we formulate a mathematical model according to the relationships between LMA, LL, leaf nitrogen, and leaf building and maintenance cost, where LMA is the fundamental variable determining the other three. We analyze the evolutionarily stable strategies (ESSs) of LMA with this mathematical model by examining the benefits of carbon and nitrogen investments to leaves in ecosystems with different N. The model shows the ESS converges to low LMA at high N and high LMA at low N. At intermediate N, there are two ESSs at low and high ends of LMA, respectively. The ESS also leads to low forest productivity by outcompeting the possible high productive strategies. We design a simulation scheme in an individual-based competition model (LM3-PPA) to simulate forest dynamics as results of the competition between deciduous and evergreen trees in three different biomes, which are temperate deciduous forest, deciduous-evergreen mixed forest, and boreal evergreen forest. The

  18. Virus Infection

    Directory of Open Access Journals (Sweden)

    Hiroshi Abe

    2013-01-01

    Full Text Available Of 168 patients with chronic hepatitis B virus (HBV infection-related liver disease, 20 patients who had received 100 mg of lamivudine plus 10 mg/day of adefovir dipivoxil (ADV (ADV group and 124 patients who had received 0.5 mg/day of entecavir or 100 mg/day of lamivudine (non-ADV group for >1 year were enrolled. For comparative analyses, 19 well-matched pairs were obtained from the groups by propensity scores. At the time of enrollment, serum creatinine and phosphate concentrations were similar between the ADV and non-ADV groups; however, urinary phosphate ( and serum bone-specific alkaline phosphatase (BAP ( concentrations were significantly higher in the ADV group than in the non-ADV group. Serum BAP was significantly higher at the time of enrollment than before ADV administration in the ADV group (, although there was no significant change in serum BAP concentration in the non-ADV group. There was a significant positive correlation between the period of ADV therapy and ΔBAP (, . Serum BAP concentration increased before increase in serum creatinine concentration and was useful for early detection of adverse events and for developing adequate measures for continuing ADV for chronic HBV infection-related liver disease.

  19. Use of Host-like Peptide Motifs in Viral Proteins Is a Prevalent Strategy in Host-Virus Interactions

    Directory of Open Access Journals (Sweden)

    Tzachi Hagai

    2014-06-01

    Full Text Available Viruses interact extensively with host proteins, but the mechanisms controlling these interactions are not well understood. We present a comprehensive analysis of eukaryotic linear motifs (ELMs in 2,208 viral genomes and reveal that viruses exploit molecular mimicry of host-like ELMs to possibly assist in host-virus interactions. Using a statistical genomics approach, we identify a large number of potentially functional ELMs and observe that the occurrence of ELMs is often evolutionarily conserved but not uniform across virus families. Some viral proteins contain multiple types of ELMs, in striking similarity to complex regulatory modules in host proteins, suggesting that ELMs may act combinatorially to assist viral replication. Furthermore, a simple evolutionary model suggests that the inherent structural simplicity of ELMs often enables them to tolerate mutations and evolve quickly. Our findings suggest that ELMs may allow fast rewiring of host-virus interactions, which likely assists rapid viral evolution and adaptation to diverse environments.

  20. CHLORELLA VIRUSES

    Science.gov (United States)

    Yamada, Takashi; Onimatsu, Hideki; Van Etten, James L.

    2007-01-01

    Chlorella viruses or chloroviruses are large, icosahedral, plaque‐forming, double‐stranded‐DNA—containing viruses that replicate in certain strains of the unicellular green alga Chlorella. DNA sequence analysis of the 330‐kbp genome of Paramecium bursaria chlorella virus 1 (PBCV‐1), the prototype of this virus family (Phycodnaviridae), predict ∼366 protein‐encoding genes and 11 tRNA genes. The predicted gene products of ∼50% of these genes resemble proteins of known function, including many that are completely unexpected for a virus. In addition, the chlorella viruses have several features and encode many gene products that distinguish them from most viruses. These products include: (1) multiple DNA methyltransferases and DNA site‐specific endonucleases, (2) the enzymes required to glycosylate their proteins and synthesize polysaccharides such as hyaluronan and chitin, (3) a virus‐encoded K+ channel (called Kcv) located in the internal membrane of the virions, (4) a SET domain containing protein (referred to as vSET) that dimethylates Lys27 in histone 3, and (5) PBCV‐1 has three types of introns; a self‐splicing intron, a spliceosomal processed intron, and a small tRNA intron. Accumulating evidence indicates that the chlorella viruses have a very long evolutionary history. This review mainly deals with research on the virion structure, genome rearrangements, gene expression, cell wall degradation, polysaccharide synthesis, and evolution of PBCV‐1 as well as other related viruses. PMID:16877063

  1. The significance of Epstein Barr Virus (EBV & DNA Topoisomerase II alpha (DNA-Topo II alpha immunoreactivity in normal oral mucosa, Oral Epithelial Dysplasia (OED and Oral Squamous Cell Carcinoma (OSCC

    Directory of Open Access Journals (Sweden)

    Osman Mohamed M

    2008-11-01

    Full Text Available Abstract Background Head and neck cancer including oral cancer is considered to develop by accumulated genetic alterations and the major pathway is cancerization from lesions such as intraepithelial dysplasia in oral leukoplakia and erythroplakia. The relationship of proliferation markers with the grading of dysplasia is uncertain. The involvement of EBV in oral carcinogenesis is not fully understood. Aim The present study was designed to investigate the role of EBV and DNA Topoisomerase II∝ (DNA-Topo II∝ during oral carcinogenesis and to examine the prognostic significance of these protein expressions in OSCCs. Methods Using specific antibodies for EBV and DNA-Topo II∝, we examined protein expressions in archival lesion tissues from 16 patients with oral epithelial dysplasia, 22 oral squamous cell carcinoma and 20 normal oral mucosa by immunohistochemistry. Clinical information was obtained through the computerized retrospective database from the tumor registry. Results DNA-Topo II∝ was expressed in all examined specimens. Analysis of Variance ANOVA revealed highly significant difference (P 0.05 in inferior surface of tongue and in hard palatal tissues. Significant differences were observed between OEDs and NSE (P Conclusion EBV and DNA Topo II-αLI expression are possible indicators in oral carcinogenesis and may be valuable diagnostic and prognostic indices in oral carcinoma.

  2. The wing-patterning network in the wingless castes of Myrmicine and Formicine ant species is a mix of evolutionarily labile and non-labile genes.

    Science.gov (United States)

    Shbailat, Seba Jamal; Abouheif, Ehab

    2013-03-01

    Wing polyphenism in ants is the ability of a single genome to produce winged or wingless castes in a colony in response to environmental cues. Although wing polyphenism is a universal and homologous feature of ants, the gene network underlying wing polyphenism is conserved in the winged castes, but is labile in the wingless castes, that is, the network is interrupted at different points in the wingless castes of different ant species. Because the expression of all genes sampled so far in this network in the wingless castes is evolutionarily labile across species, an important question is whether all "interruption points" in the network are evolutionarily labile or are there interruption points that are evolutionarily non-labile. Here we show that in the wingless castes, the expression of the gene brinker (brk), which mediates growth, patterning, and apoptosis in the Drosophila wing disc, is non-labile; it is absent in vestigial wing discs of four ants species. In contrast, the expression of engrailed (en), a gene upstream of brk is labile; it is present in some species but absent in others. In the winged castes, both brk and en expression are conserved relative to their expression in Drosophila wing discs. The differential lability of genes in the network in wingless castes may be a general feature of networks underlying polyphenic traits. This raises the possibility that some genes, like brk, may be under stabilizing selection while most others, like en, may be evolving via directional selection or neutral drift. Copyright © 2012 Wiley Periodicals, Inc.

  3. Single virus genomics: a new tool for virus discovery.

    Directory of Open Access Journals (Sweden)

    Lisa Zeigler Allen

    Full Text Available Whole genome amplification and sequencing of single microbial cells has significantly influenced genomics and microbial ecology by facilitating direct recovery of reference genome data. However, viral genomics continues to suffer due to difficulties related to the isolation and characterization of uncultivated viruses. We report here on a new approach called 'Single Virus Genomics', which enabled the isolation and complete genome sequencing of the first single virus particle. A mixed assemblage comprised of two known viruses; E. coli bacteriophages lambda and T4, were sorted using flow cytometric methods and subsequently immobilized in an agarose matrix. Genome amplification was then achieved in situ via multiple displacement amplification (MDA. The complete lambda phage genome was recovered with an average depth of coverage of approximately 437X. The isolation and genome sequencing of uncultivated viruses using Single Virus Genomics approaches will enable researchers to address questions about viral diversity, evolution, adaptation and ecology that were previously unattainable.

  4. Analysis of Dengue Virus Genetic Diversity during Human and Mosquito Infection Reveals Genetic Constraints.

    Directory of Open Access Journals (Sweden)

    October M Sessions

    Full Text Available Dengue viruses (DENV cause debilitating and potentially life-threatening acute disease throughout the tropical world. While drug development efforts are underway, there are concerns that resistant strains will emerge rapidly. Indeed, antiviral drugs that target even conserved regions in other RNA viruses lose efficacy over time as the virus mutates. Here, we sought to determine if there are regions in the DENV genome that are not only evolutionarily conserved but genetically constrained in their ability to mutate and could hence serve as better antiviral targets. High-throughput sequencing of DENV-1 genome directly from twelve, paired dengue patients' sera and then passaging these sera into the two primary mosquito vectors showed consistent and distinct sequence changes during infection. In particular, two residues in the NS5 protein coding sequence appear to be specifically acquired during infection in Ae. aegypti but not Ae. albopictus. Importantly, we identified a region within the NS3 protein coding sequence that is refractory to mutation during human and mosquito infection. Collectively, these findings provide fresh insights into antiviral targets and could serve as an approach to defining evolutionarily constrained regions for therapeutic targeting in other RNA viruses.

  5. Principles of Virus Structural Organization

    Science.gov (United States)

    Prasad, B.V. Venkataram; Schmid, Michael F

    2013-01-01

    Viruses, the molecular nanomachines infecting hosts ranging from prokaryotes to eukaryotes, come in different sizes, shapes and symmetries. Questions such as what principles govern their structural organization, what factors guide their assembly, how these viruses integrate multifarious functions into one unique structure have enamored researchers for years. In the last five decades, following Caspar and Klug's elegant conceptualization of how viruses are constructed, high resolution structural studies using X-ray crystallography and more recently cryo-EM techniques have provided a wealth of information on structures of variety of viruses. These studies have significantly furthered our understanding of the principles that underlie structural organization in viruses. Such an understanding has practical impact in providing a rational basis for the design and development of antiviral strategies. In this chapter, we review principles underlying capsid formation in a variety of viruses, emphasizing the recent developments along with some historical perspective. PMID:22297509

  6. CHANDIPURA VIRUS

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. CHANDIPURA VIRUS. First isolated from a village called Chandipura near Nagpur in 1965 in India. Belongs to rhabdoviridae family. Used as a Model System to study RNA virus multiplication in the infected cell at molecular level. Notes:

  7. Management of atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesions of the uterine cervix with human papilloma virus infection among young women aged less than 25 years.

    Science.gov (United States)

    Ryu, Ki-Jin; Lee, Sanghoon; Min, Kyung-Jin; Hong, Jin Hwa; Song, Jae Yun; Lee, Jae Kwan; Lee, Nak Woo

    2016-12-01

    Current ASCCP guidelines recommend repeat cytology 12 months after HPV-positive results in women aged 21-24 years with either atypical squamous cells of undetermined significance (ASCUS) or a low-grade squamous intraepithelial lesion (LSIL). The purpose of this study was to validate an algorithm in such women with ASCUS or LSIL. A multicenter cross-sectional study was carried out at three academic hospitals involving 40,847 Korean women who underwent cervical cancer screening with cytology and HPV testing with or without subsequent colposcopic biopsies between January 2007 and December 2013. Among a total of 3,193 women with available histopathology data, 762 women with ASCUS and 758 with LSIL were HPV-positive. Among HPV-positive women with ASCUS, 38.5% of women aged 21-24 years had ≥CIN2, compared to 20.8% of women aged 30-65 years and 21.1% of the total women. Among HPV-positive women with LSIL, 25.8% aged 21-24 years had ≥CIN2, compared to 21.2% of women aged 30-65 years and 21.9% of the total women. In HPV-positive women with ASCUS/LSIL aged less than 25 years, the prevalence of ≥CIN2 lesions was 34.5%, which was significantly higher than that (21.0%) in women aged ≥25 years. The risk of ≥CIN2 lesions in HPV-positive Korean women aged 21-24 years with ASCUS or LSIL was not lower than that in older women. Colposcopic examination should be considered for management of HPV-positive young women with ASCUS or LSIL. Diagn. Cytopathol. 2016;44:959-963. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Improving the performance of reflex Human Papilloma Virus (HPV) testing in triaging women with atypical squamous cells of undetermined significance (ASCUS): A restrospective study in a tertiary hospital in United Arab Emirates (UAE).

    Science.gov (United States)

    Fakhreldin, Marwa; Elmasry, Karim

    2016-02-03

    Cervical cancer is the second commonest cancer in women worldwide. Infection with oncogenic types of human Papillomavirus (HPV) is the most important risk factor for developing cervical cancer. Reflex High risk HPV (HR-HPV) testing is of significant value in the assessment of Papanicolaou (Pap) smear results where ASCUS are identified. To improve the performance of reflex HR-HPV testing in triage of ASCUS and analyze the factors impacting it. In this study, we generated a database of 9641 women who had cervical smears collected during the study period from the cytopathology record in a large tertiary hospital in UAE. These included 297 smears with ASCUS diagnosis. All cases were retrospectively followed up with a mean duration of 2.44 years. We analyzed data according to the outcome based on several follow-up Pap smear analysis as the reference assessment. We detected HR-HPV infection in 17.9% of cases. 9.1% ASCUS cases can be more accurate in premenopausal women upon adding age group and presenting complaint as a triage item. This improves the performance of reflex HPV testing and the subsequent selection of high risk patients for colposcopy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. "The evil virus cell": Students' knowledge and beliefs about viruses.

    Science.gov (United States)

    Simon, Uwe K; Enzinger, Sonja M; Fink, Andreas

    2017-01-01

    Education about virus biology at school is of pivotal interest to raise public awareness concerning means of disease transmission and, thus, methods to prevent infection, and to reduce unnecessary antibiotic treatment due to patient pressure on physicians in case of viral diseases such as influenza. This study aimed at making visible the knowledge of Austrian high school and university students with respect to virus biology, virus structure and health-education issues. The data presented here stem from comprehensive questionnaire analyses, including the task to draw a virus, from a cross-sectional study with 133 grade 7 and 199 grade 10 high school students, and 133 first-year biology and 181 first-year non-biology university students. Analyses were performed both quantitatively and qualitatively. ANOVA revealed a highly significant group effect for total knowledge relating to virus biology and health issues (F(3, 642) = 44.17, p virus as a pro- or eukaryotic cell, or falsely naming malaria as a viral disease. Since there was no significant difference in virus-related knowledge between high schools, virus biology seems to have been taught similarly among the tested schools. However, the majority of participants stated that the virus-related knowledge they had acquired at school was not sufficient. Based on the results presented here we urgently suggest improving and intensifying teaching this topic at school, since virus-related knowledge was by far too fragmentary among many participants. Such lack of health-relevant knowledge may contribute to pressure on physicians by patients to unnecessarily prescribe antibiotics, and possibly lead to potentially dangerous neglect concerning vaccination. The effectiveness of newly developed virus-related teaching units and material could be tested with the instrument used here.

  10. Computer viruses

    Science.gov (United States)

    Denning, Peter J.

    1988-01-01

    The worm, Trojan horse, bacterium, and virus are destructive programs that attack information stored in a computer's memory. Virus programs, which propagate by incorporating copies of themselves into other programs, are a growing menace in the late-1980s world of unprotected, networked workstations and personal computers. Limited immunity is offered by memory protection hardware, digitally authenticated object programs,and antibody programs that kill specific viruses. Additional immunity can be gained from the practice of digital hygiene, primarily the refusal to use software from untrusted sources. Full immunity requires attention in a social dimension, the accountability of programmers.

  11. Adeno-associated Virus (AAV) Serotypes Have Distinctive Interactions with Domains of the Cellular AAV Receptor

    Science.gov (United States)

    Pillay, Sirika; Zou, Wei; Cheng, Fang; Puschnik, Andreas S.; Meyer, Nancy L.; Ganaie, Safder S.; Deng, Xuefeng; Wosen, Jonathan E.; Davulcu, Omar; Yan, Ziying; Engelhardt, John F.; Brown, Kevin E.; Chapman, Michael S.

    2017-01-01

    ABSTRACT Adeno-associated virus (AAV) entry is determined by its interactions with specific surface glycans and a proteinaceous receptor(s). Adeno-associated virus receptor (AAVR) (also named KIAA0319L) is an essential cellular receptor required for the transduction of vectors derived from multiple AAV serotypes, including the evolutionarily distant serotypes AAV2 and AAV5. Here, we further biochemically characterize the AAV-AAVR interaction and define the domains within the ectodomain of AAVR that facilitate this interaction. By using a virus overlay assay, it was previously shown that the major AAV2 binding protein in membrane preparations of human cells corresponds to a glycoprotein with a molecular mass of 150 kDa. By establishing a purification procedure, performing further protein separation by two-dimensional electrophoresis, and utilizing mass spectrometry, we now show that this glycoprotein is identical to AAVR. While we find that AAVR is an N-linked glycosylated protein, this glycosylation is not a strict requirement for AAV2 binding or functional transduction. Using a combination of genetic complementation with deletion constructs and virus overlay assays with individual domains, we find that AAV2 functionally interacts predominantly with the second Ig-like polycystic kidney disease (PKD) repeat domain (PKD2) present in the ectodomain of AAVR. In contrast, AAV5 interacts primarily through the first, most membrane-distal, PKD domain (PKD1) of AAVR to promote transduction. Furthermore, other AAV serotypes, including AAV1 and -8, require a combination of PKD1 and PKD2 for optimal transduction. These results suggest that despite their shared dependence on AAVR as a critical entry receptor, different AAV serotypes have evolved distinctive interactions with the same receptor. IMPORTANCE Over the past decade, AAV vectors have emerged as leading gene delivery tools for therapeutic applications and biomedical research. However, fundamental aspects of the AAV life

  12. Extraterrestrial Viruses?

    OpenAIRE

    Jurado Hernández, Daniel José

    2017-01-01

    Fundamentals of Life - Origin and Fundamentals of Living Things. Evaluation rubric to evaluate the debate and presentation about the point of view regarding the possibility of viruses from the outer space.

  13. Zika Virus

    OpenAIRE

    Musso, Didier; Gubler, Duane J.

    2016-01-01

    Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947 and from mosquitoes in 1948 in Africa, and ZIKV infections in humans were sporadic for half a century before emerging in the Pacific and the Americas. ZIKV is usually transmitted by the bite of infected mosquitoes. The clinical presentation of Zika fever is nonspecific and can be misdiagnosed as other infectious diseases, especi...

  14. Detection, isolation, and persistence of viruses within bivalve mollusks

    Science.gov (United States)

    Norovirus (NV), hepatitis A virus (HAV), and other virus transmission by molluscan shellfish is a significant issue. Research at the ARS-Dover DE laboratory has led to the development of improved methods for detecting these viruses. To identify pathogenic viruses within mollusks, a rapid highly-se...

  15. West Nile Virus: Biology, Transmission, and Human Infection

    Science.gov (United States)

    Colpitts, Tonya M.; Conway, Michael J.; Montgomery, Ruth R.

    2012-01-01

    Summary: West Nile Virus was introduced into the Western Hemisphere during the late summer of 1999 and has been causing significant and sometimes severe human diseases since that time. This article briefly touches upon the biology of the virus and provides a comprehensive review regarding recent discoveries about virus transmission, virus acquisition, and human infection and disease. PMID:23034323

  16. Influenza Virus Infection of Marine Mammals.

    Science.gov (United States)

    Fereidouni, Sasan; Munoz, Olga; Von Dobschuetz, Sophie; De Nardi, Marco

    2016-03-01

    Interspecies transmission may play a key role in the evolution and ecology of influenza A viruses. The importance of marine mammals as hosts or carriers of potential zoonotic pathogens such as highly pathogenic H5 and H7 influenza viruses is not well understood. The fact that influenza viruses are some of the few zoonotic pathogens known to have caused infection in marine mammals, evidence for direct transmission of influenza A virus H7N7 subtype from seals to man, transmission of pandemic H1N1 influenza viruses to seals and also limited evidence for long-term persistence of influenza B viruses in seal populations without significant genetic change, makes monitoring of influenza viruses in marine mammal populations worth being performed. In addition, such monitoring studies could be a great tool to better understand the ecology of influenza viruses in nature.

  17. Cytokine Signatures Discriminate Highly Frequent Acute Hepatitis a Virus and Hepatitis E Virus Coinfections from Monoinfections in Mexican Pediatric Patients.

    Science.gov (United States)

    Realpe-Quintero, Mauricio; Copado-Villagrana, Edgar Daniel; Trujillo-Ochoa, Jorge Luis; Alvarez, Angel Hilario; Panduro, Arturo; Fierro, Nora Alma

    2017-07-01

    The frequency of hepatitis A virus and hepatitis E virus infections and their cytokine profiles were analyzed in Mexican pediatric patients with acute hepatitis. A high frequency of coinfections was found. Significant overexpression of interleukin (IL)-4, IL-12, IL-13 and interferon-gamma during hepatitis A virus monoinfections and limited secretion of cytokines in hepatitis E virus infections were observed.

  18. Newcastle Disease Virus (PDQ)

    Science.gov (United States)

    ... to Ask about Your Treatment Research Newcastle Disease Virus (PDQ®)–Patient Version Overview Go to Health Professional ... Question 8 ). Questions and Answers About Newcastle Disease Virus What is Newcastle disease virus? Newcastle disease virus ( ...

  19. Powassan (POW) Virus Basics

    Science.gov (United States)

    ... Professionals Related Topics For International Travelers Powassan (POW) Virus Basics Download this fact sheet formatted for print: ... POW) Virus Fact Sheet (PDF) What is Powassan virus? Powassan (POW) virus is a flavivirus that is ...

  20. Gastroenteritis and the novel picornaviruses aichi virus, cosavirus, saffold virus, and salivirus in young children.

    Science.gov (United States)

    Nielsen, Alex Christian Yde; Gyhrs, Mette Louise; Nielsen, Lars Peter; Pedersen, Court; Böttiger, Blenda

    2013-07-01

    During the last few years many new human picornaviruses have been discovered due to advances in metagenomics and other molecular biological approaches. The clinical significance and the occurrence are only sparsely described. To determine the epidemiology and clinical significance of infections with the novel human picornaviruses, aichi virus, cosavirus, salivirus, and saffold virus in infants in Denmark. We tested 1393 stool samples from a birth cohort of 454 children for these viruses. Samples were collected at ages 6, 10 and 15 months, and at episodes of gastroenteritis. Samples were tested by real-time reverse-transcriptase polymerase chain reaction assays. Each study participant had a diary, where the parents reported episodes of disease, including gastroenteritis. Aichi virus, salivirus and saffold virus were detected in 6, 9 and 38 of the children, respectively, but cosavirus was not detected in any of the children. There was a clear seasonal variation with most infections occurring in autumn and winter. A statistically significant association between the findings of salivirus and gastrointestinal disease was demonstrated. There was no association between gastrointestinal disease and the presence of aichi virus or saffold virus. The newly discovered human picornaviruses aichi virus, saffold virus, and salivirus are circulating in Danish children, with the most common being saffold virus. Saffold virus was seen almost exclusively in the autumn and winter period. Salivirus was the only virus, which was significantly associated with gastroenteritis, although the number of positive samples was rather low. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Computer Viruses. Technology Update.

    Science.gov (United States)

    Ponder, Tim, Comp.; Ropog, Marty, Comp.; Keating, Joseph, Comp.

    This document provides general information on computer viruses, how to help protect a computer network from them, measures to take if a computer becomes infected. Highlights include the origins of computer viruses; virus contraction; a description of some common virus types (File Virus, Boot Sector/Partition Table Viruses, Trojan Horses, and…

  2. Viruses Avian influenza, bovine herpes, bovine viral diarrhea virus ...

    Indian Academy of Sciences (India)

    ... human cytomegalovirus, herpes simplex virus, human immunodeficiency virus I, influenza, lymphocytic choriomeningitis virus, measles, papilloma, rabies, respiratory syncitial virus, simian immunodeficiency virus, simian virus 40. Bacteria Borrelia burgdorferi (Lyme disease), Moraxella bovis, Mycobacterium tuberculosis, ...

  3. Computer viruses

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, F.B.

    1986-01-01

    This thesis investigates a recently discovered vulnerability in computer systems which opens the possibility that a single individual with an average user's knowledge could cause widespread damage to information residing in computer networks. This vulnerability is due to a transitive integrity corrupting mechanism called a computer virus which causes corrupted information to spread from program to program. Experiments have shown that a virus can spread at an alarmingly rapid rate from user to user, from system to system, and from network to network, even when the best-availability security techniques are properly used. Formal definitions of self-replication, evolution, viruses, and protection mechanisms are used to prove that any system that allows sharing, general functionality, and transitivity of information flow cannot completely prevent viral attack. Computational aspects of viruses are examined, and several undecidable problems are shown. It is demonstrated that a virus may evolve so as to generate any computable sequence. Protection mechanisms are explored, and the design of computer networks that prevent both illicit modification and dissemination of information are given. Administration and protection of information networks based on partial orderings are examined, and probably correct automated administrative assistance is introduced.

  4. Virus induced inflammation and cancer development.

    Science.gov (United States)

    Read, Scott A; Douglas, Mark W

    2014-04-10

    Chronic inflammation as a result of viral infection significantly increases the likelihood of cancer development. A handful of diverse viruses have confirmed roles in cancer development and progression, but the list of suspected oncogenic viruses is continually growing. Viruses induce cancer directly and indirectly, by activating inflammatory signalling pathways and cytokines, stimulating growth of infected cells and inhibiting apoptosis. Although oncogenic viruses induce inflammation by various mechanisms, it is generally mediated by the MAPK, NFκB and STAT3 signalling pathways. This review will explore the unique mechanisms by which different oncogenic viruses induce inflammation to promote cancer initiation and progression. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  5. RNAi screening reveals requirement for host cell secretory pathway in infection by diverse families of negative-strand RNA viruses

    Science.gov (United States)

    Panda, Debasis; Das, Anshuman; Dinh, Phat X.; Subramaniam, Sakthivel; Nayak, Debasis; Barrows, Nicholas J.; Pearson, James L.; Thompson, Jesse; Kelly, David L.; Ladunga, Istvan; Pattnaik, Asit K.

    2011-01-01

    Negative-strand (NS) RNA viruses comprise many pathogens that cause serious diseases in humans and animals. Despite their clinical importance, little is known about the host factors required for their infection. Using vesicular stomatitis virus (VSV), a prototypic NS RNA virus in the family Rhabdoviridae, we conducted a human genome-wide siRNA screen and identified 72 host genes required for viral infection. Many of these identified genes were also required for infection by two other NS RNA viruses, the lymphocytic choriomeningitis virus of the Arenaviridae family and human parainfluenza virus type 3 of the Paramyxoviridae family. Genes affecting different stages of VSV infection, such as entry/uncoating, gene expression, and assembly/release, were identified. Depletion of the proteins of the coatomer complex I or its upstream effectors ARF1 or GBF1 led to detection of reduced levels of VSV RNA. Coatomer complex I was also required for infection of lymphocytic choriomeningitis virus and human parainfluenza virus type 3. These results highlight the evolutionarily conserved requirements for gene expression of diverse families of NS RNA viruses and demonstrate the involvement of host cell secretory pathway in the process. PMID:22065774

  6. Hendra virus.

    Science.gov (United States)

    Middleton, Deborah

    2014-12-01

    Hendra virus infection of horses occurred sporadically between 1994 and 2010 as a result of spill-over from the viral reservoir in Australian mainland flying-foxes, and occasional onward transmission to people also followed from exposure to affected horses. An unprecedented number of outbreaks were recorded in 2011 leading to heightened community concern. Release of an inactivated subunit vaccine for horses against Hendra virus represents the first commercially available product that is focused on mitigating the impact of a Biosafety Level 4 pathogen. Through preventing the development of acute Hendra virus disease in horses, vaccine use is also expected to reduce the risk of transmission of infection to people. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

  7. Marburg virus.

    Science.gov (United States)

    Dowdle, W R

    1976-01-01

    Marburg virus disease, which produced 20 per cent mortality when it first occured during 1967 in Germany and Yugoslavia, recently appeared again in South Africa. The source of the first outbreak was monkeys shipped from Africa; the origin of the second episode is unclear. Because distribution of the virus in nature is unknown, its threat to man cannot be readily determined. Differential laboratory diagnoses of hemorrhagic fevers should be encouraged in order to learn more about the epidemiology of these diseases and to better assess the risks which their etiologic agents may pose for attending medical personnel.

  8. Ecology of prokaryotic viruses.

    Science.gov (United States)

    Weinbauer, Markus G

    2004-05-01

    The finding that total viral abundance is higher than total prokaryotic abundance and that a significant fraction of the prokaryotic community is infected with phages in aquatic systems has stimulated research on the ecology of prokaryotic viruses and their role in ecosystems. This review treats the ecology of prokaryotic viruses ('phages') in marine, freshwater and soil systems from a 'virus point of view'. The abundance of viruses varies strongly in different environments and is related to bacterial abundance or activity suggesting that the majority of the viruses found in the environment are typically phages. Data on phage diversity are sparse but indicate that phages are extremely diverse in natural systems. Lytic phages are predators of prokaryotes, whereas lysogenic and chronic infections represent a parasitic interaction. Some forms of lysogeny might be described best as mutualism. The little existing ecological data on phage populations indicate a large variety of environmental niches and survival strategies. The host cell is the main resource for phages and the resource quality, i.e., the metabolic state of the host cell, is a critical factor in all steps of the phage life cycle. Virus-induced mortality of prokaryotes varies strongly on a temporal and spatial scale and shows that phages can be important predators of bacterioplankton. This mortality and the release of cell lysis products into the environment can strongly influence microbial food web processes and biogeochemical cycles. Phages can also affect host diversity, e.g., by 'killing the winner' and keeping in check competitively dominant species or populations. Moreover, they mediate gene transfer between prokaryotes, but this remains largely unknown in the environment. Genomics or proteomics are providing us now with powerful tools in phage ecology, but final testing will have to be performed in the environment.

  9. Significant NRC Enforcement Actions

    Data.gov (United States)

    Nuclear Regulatory Commission — This dataset provides a list of Nuclear Regulartory Commission (NRC) issued significant enforcement actions. These actions, referred to as "escalated", are issued by...

  10. Modeling The Lifecycle Of Ebola Virus Under Biosafety Level 2 Conditions With Virus-like Particles Containing Tetracistronic Minigenomes

    OpenAIRE

    Hoenen, Thomas; Watt, Ari; Mora, Anita; Feldmann, Heinz

    2014-01-01

    Ebola viruses cause severe hemorrhagic fevers in humans and non-human primates, with case fatality rates as high as 90%. There are no approved vaccines or specific treatments for the disease caused by these viruses, and work with infectious Ebola viruses is restricted to biosafety level 4 laboratories, significantly limiting the research on these viruses. Lifecycle modeling systems model the virus lifecycle under biosafety level 2 conditions; however, until recently such systems have been lim...

  11. Clustering and cellular distribution characteristics of virus particles of Tomato spotted wilt virus and Tomato zonate spot virus in different plant hosts

    National Research Council Canada - National Science Library

    Zhang, Zhongkai; Zheng, Kuanyu; Dong, Jiahong; Fang, Qi; Hong, Jian; Wang, Xifeng

    2016-01-01

    Tomato spotted wilt virus (TSWV) and Tomato zonate spot virus (TZSV) are the two dominant species of thrip-transmitted tospoviruses, cause significant losses in crop yield in Yunnan and its neighboring provinces in China...

  12. HUMAN PAPILLOMA VIRUS — ONCOGENIC VIRUS

    Directory of Open Access Journals (Sweden)

    A.N. Mayansky

    2010-01-01

    Full Text Available The lecture is devoted to oncogenic viruses, particularly human papilloma virus. Papilloma viral infection is found in all parts of the globe and highly contagious. In addition to exhaustive current data on classification, specifics of papilloma viruses composition and epidemiology, the author describes in great detail the malignization mechanisms of papilloma viruses pockets. Also, issues of diagnostics and specific prevention and treatment of diseases caused by this virus are illustrated. Key words: oncogenic viruses, papilloma viruses, prevention, vaccination. (Pediatric Pharmacology. – 2010; 7(4:48-55

  13. Limits in virus filtration capability? Impact of virus quality and spike level on virus removal with xenotropic murine leukemia virus.

    Science.gov (United States)

    Roush, David J; Myrold, Adam; Burnham, Michael S; And, Joseph V; Hughes, Joseph V

    2015-01-01

    Virus filtration (VF) is a key step in an overall viral clearance process since it has been demonstrated to effectively clear a wide range of mammalian viruses with a log reduction value (LRV) > 4. The potential to achieve higher LRV from virus retentive filters has historically been examined using bacteriophage surrogates, which commonly demonstrated a potential of > 9 LRV when using high titer spikes (e.g. 10(10) PFU/mL). However, as the filter loading increases, one typically experiences significant decreases in performance and LRV. The 9 LRV value is markedly higher than the current expected range of 4-5 LRV when utilizing mammalian retroviruses on virus removal filters (Miesegaes et al., Dev Biol (Basel) 2010;133:3-101). Recent values have been reported in the literature (Stuckey et al., Biotech Progr 2014;30:79-85) of LRV in excess of 6 for PPV and XMuLV although this result appears to be atypical. LRV for VF with therapeutic proteins could be limited by several factors including process limits (flux decay, load matrix), virus spike level and the analytical methods used for virus detection (i.e. the Limits of Quantitation), as well as the virus spike quality. Research was conducted using the Xenotropic-Murine Leukemia Virus (XMuLV) for its direct relevance to the most commonly cited document, the International Conference of Harmonization (ICH) Q5A (International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use, Geneva, Switzerland, 1999) for viral safety evaluations. A unique aspect of this work is the independent evaluation of the impact of retrovirus quality and virus spike level on VF performance and LRV. The VF studies used XMuLV preparations purified by either ultracentrifugation (Ultra 1) or by chromatographic processes that yielded a more highly purified virus stock (Ultra 2). Two monoclonal antibodies (Mabs) with markedly different filtration characteristics and with similar levels of

  14. Stability, biophysical properties and effect of ultracentrifugation and diafiltration on measles virus and mumps virus.

    Science.gov (United States)

    Sviben, Dora; Forčić, Dubravko; Kurtović, Tihana; Halassy, Beata; Brgles, Marija

    2016-06-01

    Measles virus and mumps virus (MeV and MuV) are enveloped RNA viruses used for production of live attenuated vaccines for prophylaxis of measles and mumps disease, respectively. For biotechnological production of and basic research on these viruses, the preparation of highly purified and infectious viruses is a prerequisite, and to meet that aim, knowledge of their stability and biophysical properties is crucial. Our goal was to carry out a detailed investigation of the stability of MeV and MuV under various pH, temperature, shear stress, filtration and storage conditions, as well as to evaluate two commonly used purification techniques, ultracentrifugation and diafiltration, with regard to their efficiency and effect on virus properties. Virus titers were estimated by CCID50 assay, particle size and concentration were measured by Nanoparticle tracking analysis (NTA) measurements, and the host cell protein content was determined by ELISA. The results demonstrated the stability of MuV and MeV at pH 9. Storage without stabilizer did not result in structural changes, but the reduction in infectivity after 24 hours was significant at +37 °C. Vortexing of the viruses resulted in significant particle degradation, leading to lower virus titers, whereas pipetting had much less impact on virus viability. Diafiltration resulted in higher recovery of both total and infectious virus particles than ultracentrifugation. These results provide important data for research on all upstream and downstream processes on these two viruses regarding biotechnological production and basic research.

  15. Oropuche virus: A virus present but ignored

    Directory of Open Access Journals (Sweden)

    Salim Mattar V.

    2015-09-01

    Full Text Available Bunyaviruses are RNA viruses that affect animals and plants; they have five genera and four of them affect humans: Orthobunyavirus, Nairovirus, Phlebovirus and Hantavirus. All of them are Arbovirus, except Hantavirus. The Orthobunyaviruses comprise Oropouche, Tahyna, La Crosse virus, California encephalitis virus and Heartland virus recently discovered (1. Except for Heartland virus which is transmitted by ticks of the genus Amblyoma, these Phleboviruses have as vectors mosquitoes, which bite small mammals which are able to be as reservoirs amplifiers.

  16. Comparative analysis of chrysanthemum transcriptome in response to three RNA viruses: Cucumber mosaic virus, Tomato spotted wilt virus and Potato virus X.

    Science.gov (United States)

    Choi, Hoseong; Jo, Yeonhwa; Lian, Sen; Jo, Kyoung-Min; Chu, Hyosub; Yoon, Ju-Yeon; Choi, Seung-Kook; Kim, Kook-Hyung; Cho, Won Kyong

    2015-06-01

    The chrysanthemum is one of popular flowers in the world and a host for several viruses. So far, molecular interaction studies between the chrysanthemum and viruses are limited. In this study, we carried out a transcriptome analysis of chrysanthemum in response to three different viruses including Cucumber mosaic virus (CMV), Tomato spotted wilt virus (TSWV) and Potato virus X (PVX). A chrysanthemum 135K microarray derived from expressed sequence tags was successfully applied for the expression profiles of the chrysanthemum at early stage of virus infection. Finally, we identified a total of 125, 70 and 124 differentially expressed genes (DEGs) for CMV, TSWV and PVX, respectively. Many DEGs were virus specific; however, 33 DEGs were commonly regulated by three viruses. Gene ontology (GO) enrichment analysis identified a total of 132 GO terms, and of them, six GO terms related stress response and MCM complex were commonly identified for three viruses. Several genes functioning in stress response such as chitin response and ethylene mediated signaling pathway were up-regulated indicating their involvement in establishment of host immune system. In particular, TSWV infection significantly down-regulated genes related to DNA metabolic process including DNA replication, chromatin organization, histone modification and cytokinesis, and they are mostly targeted to nucleosome and MCM complex. Taken together, our comparative transcriptome analysis revealed several genes related to hormone mediated viral stress response and DNA modification. The identified chrysanthemums genes could be good candidates for further functional study associated with resistant to various plant viruses.

  17. Propagation of Significant Figures.

    Science.gov (United States)

    Schwartz, Lowell M.

    1985-01-01

    Shows that the rules of thumb for propagating significant figures through arithmetic calculations frequently yield misleading results. Also describes two procedures for performing this propagation more reliably than the rules of thumb. However, both require considerably more calculational effort than do the rules. (JN)

  18. Mengenal Hanta Virus

    OpenAIRE

    Wijayanti, Tri

    2009-01-01

    Virus Hanta kurang infeksius, kecuali di dalam lingkungan tertentu. Lamanya waktu virus ini dapat bertahan di lingkungan, setelah keluar dari tubuh tikus tidaklah diketahui secara pasti. Tetapi percobaan laboratorium menunjukkan bahwa, daya infektifitasnya tidak dijumpai setelah dua hari pengeringan. Genus hanta virus terdiri dari 22 spesies virus, dapat menyebabkan hemorrhagic fever with renal syndrome (HFRS) dan hanta virus pulmonary syndrome (HPS).

  19. Viruses of hyperthermophilic Crenarchaea

    DEFF Research Database (Denmark)

    Prangishvili, D.; Garrett, R. A.

    2005-01-01

    , when one examines the archaeal viruses, the picture appears complex. Most viruses that are known to infect members of the kingdom Euryarchaeota resemble bacterial viruses, whereas those associated with the kingdom Crenarchaeota show little resemblance to either bacterial or eukaryal viruses....... This review summarizes our current knowledge of this group of exceptional and highly diverse archaeal viruses....

  20. Respiratory Syncytial Virus Vaccines

    OpenAIRE

    Dudas, Robert A; Karron, Ruth A.

    1998-01-01

    Respiratory syncytial virus (RSV) is the most important cause of viral lower respiratory tract illness (LRI) in infants and children worldwide and causes significant LRI in the elderly and in immunocompromised patients. The goal of RSV vaccination is to prevent serious RSV-associated LRI. There are several obstacles to the development of successful RSV vaccines, including the need to immunize very young infants, who may respond inadequately to vaccination; the existence of two antigenically d...

  1. "The evil virus cell": Students' knowledge and beliefs about viruses.

    Directory of Open Access Journals (Sweden)

    Uwe K Simon

    Full Text Available Education about virus biology at school is of pivotal interest to raise public awareness concerning means of disease transmission and, thus, methods to prevent infection, and to reduce unnecessary antibiotic treatment due to patient pressure on physicians in case of viral diseases such as influenza. This study aimed at making visible the knowledge of Austrian high school and university students with respect to virus biology, virus structure and health-education issues. The data presented here stem from comprehensive questionnaire analyses, including the task to draw a virus, from a cross-sectional study with 133 grade 7 and 199 grade 10 high school students, and 133 first-year biology and 181 first-year non-biology university students. Analyses were performed both quantitatively and qualitatively. ANOVA revealed a highly significant group effect for total knowledge relating to virus biology and health issues (F(3, 642 = 44.17, p < 0.01, η2p = 0.17. Specific post-hoc tests by means of the Tukey test showed significant differences between all groups (p < .01 with the exception of 1st year non-biology students and grade 10 high school students. Students enrolled in university-level biology outperformed all other groups, even though they had not yet encountered this topic at their courses; part of this phenomenon might be due to their affinity for learning about biological topics. However, even many first-year biology students had a high number of severe misconceptions, e.g., defining a virus as a pro- or eukaryotic cell, or falsely naming malaria as a viral disease. Since there was no significant difference in virus-related knowledge between high schools, virus biology seems to have been taught similarly among the tested schools. However, the majority of participants stated that the virus-related knowledge they had acquired at school was not sufficient. Based on the results presented here we urgently suggest improving and intensifying teaching

  2. 3D rotating wall vessel and 2D cell culture of four veterinary virus pathogens: A comparison of virus yields, portions of infectious particles and virus growth curves.

    Science.gov (United States)

    Malenovská, Hana

    2016-02-01

    Only very few comparative studies have been performed that evaluate general trends of virus growth under 3D in comparison with 2D cell culture conditions. The aim of this study was to investigate differences when four animal viruses are cultured in 2D and 3D. Suid herpesvirus 1 (SuHV-1), Vesicular stomatitis virus (VSIV), Bovine adenovirus (BAdV) and Bovine parainfluenza 3 virus (BPIV-3) were cultivated in 3D rotating wall vessels (RWVs) and conventional 2D cultures. The production of virus particles, the portion of infectious particles, and the infectious growth curves were compared. For all viruses, the production of virus particles (related to cell density), including the non-infectious ones, was lower in 3D than in 2D culture. The production of only infectious particles was significantly lower in BAdV and BPIV-3 in 3D cultures in relation to cell density. The two cultivation approaches resulted in significantly different virus particle-to-TCID50 ratios in three of the four viruses: lower in SuHV-1 and BPIV-3 and higher in BAdV in 3D culture. The infectious virus growth rates were not significantly different in all viruses. Although 3D RWV culture resulted in lower production of virus particles compared to 2D systems, the portion of infectious particles was higher for some viruses. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Biological significance of selenium

    Energy Technology Data Exchange (ETDEWEB)

    Duerre, P.; Andreesen, J.R.

    1986-02-01

    Until a few years ago, selenium was exclusively thought of as a toxic substance which was applied mainly in the optical and electrical industries. By now, many biological reactions have been detected which cannot take place without the catalytic effect of selenium. The majority of these processes was found and clarified in microorganisms; however, the anticarcinogenic properties of this trace element may well have some significance for man in future.

  4. High ethanol fermentation performance of the dry dilute acid pretreated corn stover by an evolutionarily adapted Saccharomyces cerevisiae strain.

    Science.gov (United States)

    Qureshi, Abdul Sattar; Zhang, Jian; Bao, Jie

    2015-01-01

    Ethanol fermentation was investigated at the high solids content of the dry dilute sulfuric acid pretreated corn stover feedstock using an evolutionary adapted Saccharomyces cerevisiae DQ1 strain. The evolutionary adaptation was conducted by successively transferring the S. cerevisiae DQ1 cells into the inhibitors containing corn stover hydrolysate every 12h and finally a stable yeast strain was obtained after 65 days' continuous adaptation. The ethanol fermentation performance using the adapted strain was significantly improved with the high ethanol titer of 71.40 g/L and the high yield of 80.34% in the simultaneous saccharification and fermentation (SSF) at 30% solids content. No wastewater was generated from pretreatment to fermentation steps. The results were compared with the published cellulosic ethanol fermentation cases, and the obvious advantages of the present work were demonstrated not only at the high ethanol titer and yield, but also the significant reduction of wastewater generation and potential cost reduction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Zika Virus.

    Science.gov (United States)

    Musso, Didier; Gubler, Duane J

    2016-07-01

    Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947 and from mosquitoes in 1948 in Africa, and ZIKV infections in humans were sporadic for half a century before emerging in the Pacific and the Americas. ZIKV is usually transmitted by the bite of infected mosquitoes. The clinical presentation of Zika fever is nonspecific and can be misdiagnosed as other infectious diseases, especially those due to arboviruses such as dengue and chikungunya. ZIKV infection was associated with only mild illness prior to the large French Polynesian outbreak in 2013 and 2014, when severe neurological complications were reported, and the emergence in Brazil of a dramatic increase in severe congenital malformations (microcephaly) suspected to be associated with ZIKV. Laboratory diagnosis of Zika fever relies on virus isolation or detection of ZIKV-specific RNA. Serological diagnosis is complicated by cross-reactivity among members of the Flavivirus genus. The adaptation of ZIKV to an urban cycle involving humans and domestic mosquito vectors in tropical areas where dengue is endemic suggests that the incidence of ZIKV infections may be underestimated. There is a high potential for ZIKV emergence in urban centers in the tropics that are infested with competent mosquito vectors such as Aedes aegypti and Aedes albopictus. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  6. Epidemiology of Zika virus, 1947–2007

    Science.gov (United States)

    Posen, H Joshua; Keystone, Jay S; Gubbay, Jonathan B; Morris, Shaun K

    2016-01-01

    Introduction Since 1947, Zika virus has been identified sporadically in humans in Africa and Asia; however, clinically consequential Zika virus disease had not been documented prior to the current outbreak in the Americas. Considering 6 decades have passed since the first identification of the virus, it is perhaps unexpected that Zika virus was recognised only recently as capable of causing disease epidemics. Substantial work on understanding the epidemiology of Zika virus has been conducted since the virus' first outbreak in 2007 in Micronesia; however, there has been little study of the earlier data on Zika virus. Methods A systematic literature search was conducted to identify evidence of Zika virus infection in humans from 1947 to 2007. Data extracted included seroprevalence of Zika virus infection, age distributions of positive test results and serologic test modalities used. Country-level and age-specific seroprevalence was calculated. Estimates of seroprevalence by different serologic test modalities were compared. Results 12 026 citations were retrieved by the literature search, and 76 articles were included in this review. Evidence of Zika virus infection in humans was found in 29 countries in Africa, 8 countries in Asia and 1 country in Europe. Country-level seroprevalence of Zika virus infection ranged from 0.4% to 53.3%. Seroprevalence of Zika virus infection was found to increase across the lifespan; 15–40% of reproductive-age individuals may have been previously infected. No significant difference was found between estimates of seroprevalence by different serologic test modalities. Discussion Zika virus has likely been endemic for decades in certain regions of the world; however, the majority of reproductive-age individuals have likely not been infected. Historical evidence of Zika virus infection exists regardless of the serologic test modality used. PMID:28588942

  7. Infectious haematopoietic necrosis virus: Chapter 2

    Science.gov (United States)

    Leong, Jo-Ann; Kurath, Gael

    2017-01-01

    Infectious haematopoietic necrosis virus (IHNV) is a Rhabdovirus that causes significant disease in Pacific salmon (Oncorhynchus spp.), Atlantic salmon (Salmo salar), and rainbow and steelhead trout (O. mykiss). IHNV causes necrosis of the haematopoietic tissues, and consequently it was named infectious haematopoietic necrosis. This virus is waterborne and may transmit horizontally and vertically through virus associated with seminal and ovarian fluids. The clinical signs of disease and diagnosis; pathology; pathophysiology; and control strategies against IHNV are discussed.

  8. [An update on Lassa virus].

    Science.gov (United States)

    Leparc-Goffart, I; Emonet, S F

    2011-12-01

    Lassa virus, the etiologic agent of Lassa hemorrhagic fever, infects 100,000 to 300,000 people every year in West Africa with an overall mortality rate ranging from 1 to 2%. It was discovered in 1969 and remains a significant public health risk in endemic areas. Because airborne transmission is possible and mortality can be high under certain conditions, Lassa virus has been classified as a category A bioterrorism agent. Early diagnosis is difficult due to insidious non-specific onset and to the great genetic divergence of the virus that makes RT-PCR assays unreliable. The lack of proper diagnostic tools promotes nosocomial infection and diminishes the efficacy of treatment. Recently, numerous advances have been made in the development of both diagnostic and vaccination techniques. The purpose of this review is to present an update on that research as well as the current epidemiology of Lassa virus.

  9. In Silico Analysis of Gene Expression Network Components Underlying Pigmentation Phenotypes in the Python Identified Evolutionarily Conserved Clusters of Transcription Factor Binding Sites

    Directory of Open Access Journals (Sweden)

    Kristopher J. L. Irizarry

    2016-01-01

    Full Text Available Color variation provides the opportunity to investigate the genetic basis of evolution and selection. Reptiles are less studied than mammals. Comparative genomics approaches allow for knowledge gained in one species to be leveraged for use in another species. We describe a comparative vertebrate analysis of conserved regulatory modules in pythons aimed at assessing bioinformatics evidence that transcription factors important in mammalian pigmentation phenotypes may also be important in python pigmentation phenotypes. We identified 23 python orthologs of mammalian genes associated with variation in coat color phenotypes for which we assessed the extent of pairwise protein sequence identity between pythons and mouse, dog, horse, cow, chicken, anole lizard, and garter snake. We next identified a set of melanocyte/pigment associated transcription factors (CREB, FOXD3, LEF-1, MITF, POU3F2, and USF-1 that exhibit relatively conserved sequence similarity within their DNA binding regions across species based on orthologous alignments across multiple species. Finally, we identified 27 evolutionarily conserved clusters of transcription factor binding sites within ~200-nucleotide intervals of the 1500-nucleotide upstream regions of AIM1, DCT, MC1R, MITF, MLANA, OA1, PMEL, RAB27A, and TYR from Python bivittatus. Our results provide insight into pigment phenotypes in pythons.

  10. Noncoding Subgenomic Flavivirus RNA Is Processed by the Mosquito RNA Interference Machinery and Determines West Nile Virus Transmission by Culex pipiens Mosquitoes.

    Science.gov (United States)

    Göertz, G P; Fros, J J; Miesen, P; Vogels, C B F; van der Bent, M L; Geertsema, C; Koenraadt, C J M; van Rij, R P; van Oers, M M; Pijlman, G P

    2016-11-15

    Flaviviruses, such as Zika virus, yellow fever virus, dengue virus, and West Nile virus (WNV), are a serious concern for human health. Flaviviruses produce an abundant noncoding subgenomic flavivirus RNA (sfRNA) in infected cells. sfRNA results from stalling of the host 5'-3' exoribonuclease XRN1/Pacman on conserved RNA structures in the 3' untranslated region (UTR) of the viral genomic RNA. sfRNA production is conserved in insect-specific, mosquito-borne, and tick-borne flaviviruses and flaviviruses with no known vector, suggesting a pivotal role for sfRNA in the flavivirus life cycle. Here, we investigated the function of sfRNA during WNV infection of Culex pipiens mosquitoes and evaluated its role in determining vector competence. An sfRNA1-deficient WNV was generated that displayed growth kinetics similar to those of wild-type WNV in both RNA interference (RNAi)-competent and -compromised mosquito cell lines. Small-RNA deep sequencing of WNV-infected mosquitoes indicated an active small interfering RNA (siRNA)-based antiviral response for both the wild-type and sfRNA1-deficient viruses. Additionally, we provide the first evidence that sfRNA is an RNAi substrate in vivo Two reproducible small-RNA hot spots within the 3' UTR/sfRNA of the wild-type virus mapped to RNA stem-loops SL-III and 3' SL, which stick out of the three-dimensional (3D) sfRNA structure model. Importantly, we demonstrate that sfRNA-deficient WNV displays significantly decreased infection and transmission rates in vivo when administered via the blood meal. Finally, we show that transmission and infection rates are not affected by sfRNA after intrathoracic injection, thereby identifying sfRNA as a key driver to overcome the mosquito midgut infection barrier. This is the first report to describe a key biological function of sfRNA for flavivirus infection of the arthropod vector, providing an explanation for the strict conservation of sfRNA production. Understanding the flavivirus transmission

  11. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and ... Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus ...

  12. Zika Virus and Pregnancy

    Science.gov (United States)

    ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus ...

  13. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus ...

  14. Computer Viruses: An Overview.

    Science.gov (United States)

    Marmion, Dan

    1990-01-01

    Discusses the early history and current proliferation of computer viruses that occur on Macintosh and DOS personal computers, mentions virus detection programs, and offers suggestions for how libraries can protect themselves and their users from damage by computer viruses. (LRW)

  15. Virus Ebola Asia

    OpenAIRE

    Wuryadi, Suharyono

    1996-01-01

    Virus Marburg dan Ebola diklasifikasikan sebagai virus yang sangat menular dan dimasukkan dalam klasifikasi sebagai virus/pathogen dengan derajat biosafety 4, sehingga untuk menanganinya diperlukan laboratorium khusus tingkat 4.

  16. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and Pregnancy Page ... Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus if you ...

  17. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your ...

  18. "The evil virus cell": Students‘ knowledge and beliefs about viruses

    Science.gov (United States)

    Enzinger, Sonja M.; Fink, Andreas

    2017-01-01

    Education about virus biology at school is of pivotal interest to raise public awareness concerning means of disease transmission and, thus, methods to prevent infection, and to reduce unnecessary antibiotic treatment due to patient pressure on physicians in case of viral diseases such as influenza. This study aimed at making visible the knowledge of Austrian high school and university students with respect to virus biology, virus structure and health-education issues. The data presented here stem from comprehensive questionnaire analyses, including the task to draw a virus, from a cross-sectional study with 133 grade 7 and 199 grade 10 high school students, and 133 first-year biology and 181 first-year non-biology university students. Analyses were performed both quantitatively and qualitatively. ANOVA revealed a highly significant group effect for total knowledge relating to virus biology and health issues (F(3, 642) = 44.17, p biology students and grade 10 high school students. Students enrolled in university-level biology outperformed all other groups, even though they had not yet encountered this topic at their courses; part of this phenomenon might be due to their affinity for learning about biological topics. However, even many first-year biology students had a high number of severe misconceptions, e.g., defining a virus as a pro- or eukaryotic cell, or falsely naming malaria as a viral disease. Since there was no significant difference in virus-related knowledge between high schools, virus biology seems to have been taught similarly among the tested schools. However, the majority of participants stated that the virus-related knowledge they had acquired at school was not sufficient. Based on the results presented here we urgently suggest improving and intensifying teaching this topic at school, since virus-related knowledge was by far too fragmentary among many participants. Such lack of health-relevant knowledge may contribute to pressure on physicians by

  19. Competitive virus assay method for titration of noncytopathogenic bovine viral diarrhea viruses (END⁺ and END⁻ viruses).

    Science.gov (United States)

    Muhsen, Mahmod; Ohi, Kota; Aoki, Hiroshi; Ikeda, Hidetoshi; Fukusho, Akio

    2013-03-01

    A new, reliable and secure virus assay method, named the competitive virus assay (CVA) method, has been established for the titration of bovine viral diarrhea viruses (BVDVs) that either show the exaltation of Newcastle disease virus (END) phenomenon or heterologous interference phenomenon (but not the END phenomenon). This method is based on the principle of (1) homologous interference between BVDVs, by using BVDV RK13/E(-) or BVDV RK13/E(+) strains as competitor virus, and (2) END phenomenon and heterologous interference, by using attenuated Newcastle disease virus (NDV) TCND strain as challenge virus. In titration of BVDV END(+) and BVDV END(-) viruses, no significant difference in estimated virus titer was observed between CVA and conventional methods. CVA method demonstrated comparable levels of sensitivity and accuracy as conventional END and interference methods, which require the use of a velogenic Miyadera strain of NDV and vesicular stomatitis virus (VSV), both of which are agents of high-risk diseases. As such, the CVA method is a safer alternative, with increased bio-safety and bio-containment, through avoidance of virulent strains that are commonly employed with conventional methods. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Computer Virus and Trends

    OpenAIRE

    Tutut Handayani; Soenarto Usna,Drs.MMSI

    2004-01-01

    Since its appearance the first time in the mid-1980s, computer virus has invited various controversies that still lasts to this day. Along with the development of computer systems technology, viruses komputerpun find new ways to spread itself through a variety of existing communications media. This paper discusses about some things related to computer viruses, namely: the definition and history of computer viruses; the basics of computer viruses; state of computer viruses at this time; and ...

  1. Normative significance of transnationalism?

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2010-01-01

    The paper concerns the specific transnational aspects of the ‘cartoons controversy' over the publication of 12 drawings of the Prophet Muhammad in the Danish newspaper Jyllands-Posten. Transnationalism denotes the relationships that are not international (between states) or domestic (between states...... and citizens, or between groups or individuals within a state). The paper considers whether the specifically transnational aspects of the controversy are normatively significant, that is, whether transnationalism makes a difference for the applicability or strength of normative considerations concerning...... publications such as the Danish cartoons. It is argued that, although some of the usual arguments about free speech only or mainly apply domestically, many also apply transnationally; that standard arguments for multicultural recognition are difficult to apply transnationally; and that requirements of respect...

  2. G-quadruplex DNA sequences are evolutionarily conserved and associated with distinct genomic features in Saccharomyces cerevisiae.

    Science.gov (United States)

    Capra, John A; Paeschke, Katrin; Singh, Mona; Zakian, Virginia A

    2010-07-22

    G-quadruplex DNA is a four-stranded DNA structure formed by non-Watson-Crick base pairing between stacked sets of four guanines. Many possible functions have been proposed for this structure, but its in vivo role in the cell is still largely unresolved. We carried out a genome-wide survey of the evolutionary conservation of regions with the potential to form G-quadruplex DNA structures (G4 DNA motifs) across seven yeast species. We found that G4 DNA motifs were significantly more conserved than expected by chance, and the nucleotide-level conservation patterns suggested that the motif conservation was the result of the formation of G4 DNA structures. We characterized the association of conserved and non-conserved G4 DNA motifs in Saccharomyces cerevisiae with more than 40 known genome features and gene classes. Our comprehensive, integrated evolutionary and functional analysis confirmed the previously observed associations of G4 DNA motifs with promoter regions and the rDNA, and it identified several previously unrecognized associations of G4 DNA motifs with genomic features, such as mitotic and meiotic double-strand break sites (DSBs). Conserved G4 DNA motifs maintained strong associations with promoters and the rDNA, but not with DSBs. We also performed the first analysis of G4 DNA motifs in the mitochondria, and surprisingly found a tenfold higher concentration of the motifs in the AT-rich yeast mitochondrial DNA than in nuclear DNA. The evolutionary conservation of the G4 DNA motif and its association with specific genome features supports the hypothesis that G4 DNA has in vivo functions that are under evolutionary constraint.

  3. G-quadruplex DNA sequences are evolutionarily conserved and associated with distinct genomic features in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    John A Capra

    2010-07-01

    Full Text Available G-quadruplex DNA is a four-stranded DNA structure formed by non-Watson-Crick base pairing between stacked sets of four guanines. Many possible functions have been proposed for this structure, but its in vivo role in the cell is still largely unresolved. We carried out a genome-wide survey of the evolutionary conservation of regions with the potential to form G-quadruplex DNA structures (G4 DNA motifs across seven yeast species. We found that G4 DNA motifs were significantly more conserved than expected by chance, and the nucleotide-level conservation patterns suggested that the motif conservation was the result of the formation of G4 DNA structures. We characterized the association of conserved and non-conserved G4 DNA motifs in Saccharomyces cerevisiae with more than 40 known genome features and gene classes. Our comprehensive, integrated evolutionary and functional analysis confirmed the previously observed associations of G4 DNA motifs with promoter regions and the rDNA, and it identified several previously unrecognized associations of G4 DNA motifs with genomic features, such as mitotic and meiotic double-strand break sites (DSBs. Conserved G4 DNA motifs maintained strong associations with promoters and the rDNA, but not with DSBs. We also performed the first analysis of G4 DNA motifs in the mitochondria, and surprisingly found a tenfold higher concentration of the motifs in the AT-rich yeast mitochondrial DNA than in nuclear DNA. The evolutionary conservation of the G4 DNA motif and its association with specific genome features supports the hypothesis that G4 DNA has in vivo functions that are under evolutionary constraint.

  4. A Functional Genomic Screen for Evolutionarily Conserved Genes Required for Lifespan and Immunity in Germline-Deficient C. elegans

    Science.gov (United States)

    Sinha, Amit; Rae, Robbie

    2014-01-01

    The reproductive system regulates lifespan in insects, nematodes and vertebrates. In Caenorhabditis elegans removal of germline increases lifespan by 60% which is dependent upon insulin signaling, nuclear hormone signaling, autophagy and fat metabolism and their microRNA-regulators. Germline-deficient C. elegans are also more resistant to various bacterial pathogens but the underlying molecular mechanisms are largely unknown. Firstly, we demonstrate that previously identified genes that regulate the extended lifespan of germline-deficient C. elegans (daf-2, daf-16, daf-12, tcer-1, mir-7.1 and nhr-80) are also essential for resistance to the pathogenic bacterium Xenorhabdus nematophila. We then use a novel unbiased approach combining laser cell ablation, whole genome microarrays, RNAi screening and exposure to X. nematophila to generate a comprehensive genome-wide catalog of genes potentially required for increased lifespan and innate immunity in germline-deficient C. elegans. We find 3,440 genes to be upregulated in C. elegans germline-deficient animals in a gonad dependent manner, which are significantly enriched for genes involved in insulin signaling, fatty acid desaturation, translation elongation and proteasome complex function. Using RNAi against a subset of 150 candidate genes selected from the microarray results, we show that the upregulated genes such as transcription factor DAF-16/FOXO, the PTEN homolog lipid phosphatase DAF-18 and several components of the proteasome complex (rpn-6.1, rpn-7, rpn-9, rpn-10, rpt-6, pbs-3 and pbs-6) are essential for both lifespan and immunity of germline deficient animals. We also identify a novel role for genes including par-5 and T12G3.6 in both lifespan-extension and increased survival on X. nematophila. From an evolutionary perspective, most of the genes differentially expressed in germline deficient C. elegans also show a conserved expression pattern in germline deficient Pristionchus pacificus, a nematode species

  5. The brighter (and evolutionarily older) face of the metabolic syndrome: evidence from Trypanosoma cruzi infection in CD-1 mice.

    Science.gov (United States)

    Brima, Wunnie; Eden, Daniel J; Mehdi, Syed Faizan; Bravo, Michelle; Wiese, Mohammad M; Stein, Joanna; Almonte, Vanessa; Zhao, Dazhi; Kurland, Irwin; Pessin, Jeffrey E; Zima, Tomas; Tanowitz, Herbert B; Weiss, Louis M; Roth, Jesse; Nagajyothi, Fnu

    2015-05-01

    Infection with Trypanosoma cruzi, the protozoan parasite that causes Chagas disease, results in chronic infection that leads to cardiomyopathy with increased mortality and morbidity in endemic regions. In a companion study, our group found that a high-fat diet (HFD) protected mice from T. cruzi-induced myocardial damage and significantly reduced post-infection mortality during acute T. cruzi infection. In the present study metabolic syndrome was induced prior to T. cruzi infection by feeding a high fat diet. Also, mice were treated with anti-diabetic drug metformin. In the present study, the lethality of T. cruzi (Brazil strain) infection in CD-1 mice was reduced from 55% to 20% by an 8-week pre-feeding of an HFD to induce obesity and metabolic syndrome. The addition of metformin reduced mortality to 3%. It is an interesting observation that both the high fat diet and the metformin, which are known to differentially attenuate host metabolism, effectively modified mortality in T. cruzi-infected mice. In humans, the metabolic syndrome, as presently construed, produces immune activation and metabolic alterations that promote complications of obesity and diseases of later life, such as myocardial infarction, stroke, diabetes, Alzheimer's disease and cancer. Using an evolutionary approach, we hypothesized that for millions of years, the channeling of host resources into immune defences starting early in life ameliorated the effects of infectious diseases, especially chronic infections, such as tuberculosis and Chagas disease. In economically developed countries in recent times, with control of the common devastating infections, epidemic obesity and lengthening of lifespan, the dwindling benefits of the immune activation in the first half of life have been overshadowed by the explosion of the syndrome's negative effects in later life. Copyright © 2015 John Wiley & Sons, Ltd.

  6. VHS virus - present situation

    DEFF Research Database (Denmark)

    Olesen, Niels Jørgen; Skall, Helle Frank

    of the worldwide distribution of the disease will be given. Virus evolution: Recent studies indicate that only a few amino acid changes in the structural proteins of VHSV can change the virulence patterns significantly, thereby coming closer to assessing the risk of none to low virulent viruses becoming high......Geographic distribution: VHSV can be divided into 4 genotypes and at least 8 subtypes and there is a close linkage between genotypes, geographic range and affected fish species. VHS is still only reported from the Northern hemisphere- and while countries like Denmark, Norway and England have freed...... themselves for VHS, several countries are still struggling with the disease. An update on the recent VHS outbreaks in rainbow trout in Iran, in olive flounder in Korea, in wrasse in Scotland, in turbot in Turkey, in a number of fish species in the great lakes in USA and Canada, and a general overview...

  7. VHS virus - present situation

    DEFF Research Database (Denmark)

    Skall, Helle Frank; Olesen, Niels Jørgen

    2015-01-01

    of the worldwide distribution of the disease will be given. Virus evolution: Recent studies indicate that only a few amino acid changes in the structural proteins of VHSV can change the virulence patterns significantly, thereby coming closer to assessing the risk of none to low virulent viruses becoming high......Geographic distribution: VHSV can be divided into 4 genotypes and at least 8 subtypes and there is a close linkage between genotypes, geographic range and affected fish species. VHS is still only reported from the Northern hemisphere- and while countries like Denmark, Norway and England have freed...... themselves for VHS, several countries are still struggling with the disease. An update on the recent VHS outbreaks in rainbow trout in Iran, in olive flounder in Korea, in wrasse in Scotland, in turbot in Turkey, in a number of fish species in the great lakes in USA and Canada, and a general overview...

  8. Viruses exploiting peroxisomes.

    Science.gov (United States)

    Lazarow, Paul B

    2011-08-01

    Viruses that are of great importance for global public health, including HIV, influenza and rotavirus, appear to exploit a remarkable organelle, the peroxisome, during intracellular replication in human cells. Peroxisomes are sites of lipid biosynthesis and catabolism, reactive oxygen metabolism, and other metabolic pathways. Viral proteins are targeted to peroxisomes (the spike protein of rotavirus) or interact with peroxisomal proteins (HIV's Nef and influenza's NS1) or use the peroxisomal membrane for RNA replication. The Nef interaction correlates strongly with the crucial Nef function of CD4 downregulation. Viral exploitation of peroxisomal lipid metabolism appears likely. Mostly, functional significance and mechanisms remain to be elucidated. Recently, peroxisomes were discovered to play a crucial role in the innate immune response by signaling the presence of intracellular virus, leading to the first rapid antiviral response. This review unearths, interprets and connects old data, in the hopes of stimulating new and promising research. Copyright © 2011. Published by Elsevier Ltd.

  9. Mechanisms of Virus Assembly

    Science.gov (United States)

    Perlmutter, Jason D.; Hagan, Michael F.

    2015-01-01

    Viruses are nanoscale entities containing a nucleic acid genome encased in a protein shell called a capsid, and in some cases surrounded by a lipid bilayer membrane. This review summarizes the physics that govern the processes by which capsids assembles within their host cells and in vitro. We describe the thermodynamics and kinetics for assembly of protein subunits into icosahedral capsid shells, and how these are modified in cases where the capsid assembles around a nucleic acid or on a lipid bilayer. We present experimental and theoretical techniques that have been used to characterize capsid assembly, and we highlight aspects of virus assembly which are likely to receive significant attention in the near future. PMID:25532951

  10. Quantification and localization of Watermelon chlorotic stunt virus and Tomato yellow leaf curl virus (Geminiviridae in populations of Bemisia tabaci (Hemiptera, Aleyrodidae with differential virus transmission characteristics.

    Directory of Open Access Journals (Sweden)

    Mario Kollenberg

    Full Text Available Bemisia tabaci (Gennadius is one of the economically most damaging insects to crops in tropical and subtropical regions. Severe damage is caused by feeding and more seriously by transmitting viruses. Those of the genus begomovirus (Geminiviridae cause the most significant crop diseases and are transmitted by B. tabaci in a persistent circulative mode, a process which is largely unknown. To analyze the translocation and to identify critical determinants for transmission, two populations of B. tabaci MEAM1 were compared for transmitting Watermelon chlorotic stunt virus (WmCSV and Tomato yellow leaf curl virus (TYLCV. Insect populations were chosen because of their high and respectively low virus transmission efficiency to compare uptake and translocation of virus through insects. Both populations harbored Rickettsia, Hamiltonella and Wolbachia in comparable ratios indicating that endosymbionts might not contribute to the different transmission rates. Quantification by qPCR revealed that WmCSV uptake and virus concentrations in midguts and primary salivary glands were generally higher than TYLCV due to higher virus contents of the source plants. Both viruses accumulated higher in insects from the efficiently compared to the poorly transmitting population. In the latter, virus translocation into the hemolymph was delayed and virus passage was impeded with limited numbers of viruses translocated. FISH analysis confirmed these results with similar virus distribution found in excised organs of both populations. No virus accumulation was found in the midgut lumen of the poor transmitter because of a restrained virus translocation. Results suggest that the poorly transmitting population comprised insects that lacked transmission competence. Those were selected to develop a population that lacks virus transmission. Investigations with insects lacking transmission showed that virus concentrations in midguts were reduced and only negligible virus amounts

  11. Water quality indicators: bacteria, coliphages, enteric viruses.

    Science.gov (United States)

    Lin, Johnson; Ganesh, Atheesha

    2013-12-01

    Water quality through the presence of pathogenic enteric microorganisms may affect human health. Coliform bacteria, Escherichia coli and coliphages are normally used as indicators of water quality. However, the presence of above-mentioned indicators do not always suggest the presence of human enteric viruses. It is important to study human enteric viruses in water. Human enteric viruses can tolerate fluctuating environmental conditions and survive in the environment for long periods of time becoming causal agents of diarrhoeal diseases. Therefore, the potential of human pathogenic viruses as significant indicators of water quality is emerging. Human Adenoviruses and other viruses have been proposed as suitable indices for the effective identification of such organisms of human origin contaminating water systems. This article reports on the recent developments in the management of water quality specifically focusing on human enteric viruses as indicators.

  12. Genome rearrangement affects RNA virus adaptability on prostate cancer cells

    Directory of Open Access Journals (Sweden)

    Kendra ePesko

    2015-04-01

    Full Text Available Gene order is often highly conserved within taxonomic groups, such that organisms with rearranged genomes tend to be less fit than wildtype gene orders, and suggesting natural selection favors genome architectures that maximize fitness. But it is unclear whether rearranged genomes hinder adaptability: capacity to evolutionarily improve in a new environment. Negative-sense nonsegmented RNA viruses (order Mononegavirales have specific genome architecture: 3′ UTR – core protein genes – envelope protein genes – RNA-dependent RNA-polymerase gene – 5′ UTR. To test how genome architecture affects RNA virus evolution, we examined vesicular stomatitis virus (VSV variants with the nucleocapsid (N gene moved sequentially downstream in the genome. Because RNA polymerase stuttering in VSV replication causes greater mRNA production in upstream genes, N-gene translocation towards the 5’ end leads to stepwise decreases in N transcription, viral replication and progeny production, and also impacts the activation of type 1 interferon mediated antiviral responses. We evolved VSV gene-order variants in two prostate cancer cell lines: LNCap cells deficient in innate immune response to viral infection, and PC3 cells that mount an IFN stimulated anti-viral response to infection. We observed that gene order affects phenotypic adaptability (reproductive growth; viral suppression of immune function, especially on PC3 cells that strongly select against virus infection. Overall, populations derived from the least-fit ancestor (most-altered N position architecture adapted fastest, consistent with theory predicting populations with low initial fitness should improve faster in evolutionary time. Also, we observed correlated responses to selection, where viruses improved across both hosts, rather than suffer fitness trade-offs on unselected hosts. Whole genomics revealed multiple mutations in evolved variants, some of which were conserved across selective

  13. Characterization of uncultivable bat influenza virus using a replicative synthetic virus.

    Directory of Open Access Journals (Sweden)

    Bin Zhou

    2014-10-01

    Full Text Available Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e.g., Ebola, SARS-CoV. Recently, influenza virus-like sequences were identified in bats; however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1. This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2 showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans; however, they provide new insights into the evolution and basic biology of influenza viruses.

  14. Effect of repeated Ribavirin treatment on grapevine viruses.

    Science.gov (United States)

    Komínek, P; Komínková, M; Jandová, B

    The effect of Ribavirin treatment for the chemotherapy of several grapevine viruses was evaluated. Four grapevine cultivars were repeatedly treated with Ribavirin in two different concentrations and with three different lengths of treatment. Repeating the Ribavirin treatment always had a significant effect on the number of healthy grapevine plants obtained. Ribavirin concentration and length of exposure showed a significant difference in sanitation of the Grapevine rupestris stem pitting-associated virus. During sanitation of the Grapevine Pinot gris virus and Grapevine fleck virus, those two factors did not show significant differences in the elimination of grapevine viruses.

  15. Another Really, Really Big Virus

    Directory of Open Access Journals (Sweden)

    James L. Van Etten

    2011-01-01

    Full Text Available Viruses with genomes larger than 300 kb and up to 1.2 Mb, which encode hundreds of proteins, are being discovered and characterized with increasing frequency. Most, but not all, of these large viruses (often referred to as giruses infect protists that live in aqueous environments. Bioinformatic analyses of metagenomes of aqueous samples indicate that large DNA viruses are quite common in nature and await discovery. One issue that is perhaps not appreciated by the virology community is that large viruses, even those classified in the same family, can differ significantly in morphology, lifestyle, and gene complement. This brief commentary, which will mention some of these unique properties, was stimulated by the characterization of the newest member of this club, virus CroV (Fischer, M.G.; Allen, M.J.; Wilson, W.H.; Suttle, C.A. Giant virus with a remarkable complement of genes infects marine zooplankton. Proc. Natl. Acad. Sci. USA 2010, 107, 19508-19513 [1]. CroV has a 730 kb genome (with ~544 protein-encoding genes and infects the marine microzooplankton Cafeteria roenbergensis producing a lytic infection.

  16. A DNA virus of Drosophila.

    Directory of Open Access Journals (Sweden)

    Robert L Unckless

    Full Text Available Little is known about the viruses infecting most species. Even in groups as well-studied as Drosophila, only a handful of viruses have been well-characterized. A viral metagenomic approach was used to explore viral diversity in 83 wild-caught Drosophila innubila, a mushroom feeding member of the quinaria group. A single fly that was injected with, and died from, Drosophila C Virus (DCV was added to the sample as a control. Two-thirds of reads in the infected sample had DCV as the best BLAST hit, suggesting that the protocol developed is highly sensitive. In addition to the DCV hits, several sequences had Oryctes rhinoceros Nudivirus, a double-stranded DNA virus, as a best BLAST hit. The virus associated with these sequences was termed Drosophila innubila Nudivirus (DiNV. PCR screens of natural populations showed that DiNV was both common and widespread taxonomically and geographically. Electron microscopy confirms the presence of virions in fly fecal material similar in structure to other described Nudiviruses. In 2 species, D. innubila and D. falleni, the virus is associated with a severe (∼80-90% loss of fecundity and significantly decreased lifespan.

  17. Animal Viruses Probe dataset (AVPDS) for microarray-based diagnosis and identification of viruses.

    Science.gov (United States)

    Yadav, Brijesh S; Pokhriyal, Mayank; Vasishtha, Dinesh P; Sharma, Bhaskar

    2014-03-01

    AVPDS (Animal Viruses Probe dataset) is a dataset of virus-specific and conserve oligonucleotides for identification and diagnosis of viruses infecting animals. The current dataset contain 20,619 virus specific probes for 833 viruses and their subtypes and 3,988 conserved probes for 146 viral genera. Dataset of virus specific probe has been divided into two fields namely virus name and probe sequence. Similarly conserved probes for virus genera table have genus, and subgroup within genus name and probe sequence. The subgroup within genus is artificially divided subgroups with no taxonomic significance and contains probes which identifies viruses in that specific subgroup of the genus. Using this dataset we have successfully diagnosed the first case of Newcastle disease virus in sheep and reported a mixed infection of Bovine viral diarrhea and Bovine herpesvirus in cattle. These dataset also contains probes which cross reacts across species experimentally though computationally they meet specifications. These probes have been marked. We hope that this dataset will be useful in microarray-based detection of viruses. The dataset can be accessed through the link https://dl.dropboxusercontent.com/u/94060831/avpds/HOME.html.

  18. Hepatitis B and C Viruses Infections and Their Association with Human Immunodeficiency Virus: A Cross-Sectional Study among Blood Donors in Ethiopia.

    Science.gov (United States)

    Yami, Alemeshet; Alemseged, Fissehaye; Hassen, Alima

    2011-03-01

    statistically significant association with Human Immunodeficiency and Hepatitis B virus infections where females were less likely to be infected. As age increases above 20 years, the risk of infection with Human Immunodeficiency Virus or Hepatitis B Virus increases. There was no association between Hepatitis B Virus, Hepatitis C Virus and Human Immunodeficiency Virus. the prevalence rate of Hepatitis B Virus, Hepatitis C Virus and Human Immunodeficiency Virus infections among blood donors in Jimma University specialized hospital were lower as compared to previous studies, in addition there was no association between Hepatitis B Virus, Hepatitis C Virus and Human Immunodeficiency Virus. Thus, community based study should be conducted to confirm the relationship of Hepatitis B Virus, Hepatitis C Virus and Human Immunodeficiency Virus.

  19. New thrips-transmitted plant viruses in Florida crops

    Science.gov (United States)

    The thrips-transmitted tospoviruses Tomato spotted wilt virus, Groundnut ringspot virus and Tomato chlorotic spot virus are present in south Florida. All three species cause economically significant disease in vegetable and ornamental crops, and may also be problematic in peanut. Control of both t...

  20. DEVELOPMENT OF A MOLECULAR METHOD TO IDENTIFY HEPATITIS E VIRUS

    Science.gov (United States)

    Hepatitis E virus (HEV) is a waterborne emerging pathogen that causes significant illness in the developing world. Thus far, an HEV outbreak has not been reported in the U.S., although a swine variant of the virus is common in Midwestern hogs. Because viruses isolated from two ...

  1. Subcellular targeting of an evolutionarily conserved plant defensin MtDef4.2 determines the outcome of plant-pathogen interaction in transgenic Arabidopsis.

    Science.gov (United States)

    Kaur, Jagdeep; Thokala, Mercy; Robert-Seilaniantz, Alexandre; Zhao, Patrick; Peyret, Hadrien; Berg, Howard; Pandey, Sona; Jones, Jonathan; Shah, Dilip

    2012-12-01

    The Medicago truncatula gene encoding an evolutionarily conserved antifungal defensin MtDef4.2 was cloned and characterized. In silico expression analysis indicated that MtDef4.2 is expressed in many tissues during the normal growth and development of M. truncatula. MtDef4.2 exhibits potent broad-spectrum antifungal activity against various Fusarium spp. Transgenic Arabidopsis thaliana lines in which MtDef4.2 was targeted to three different subcellular compartments were generated. These lines were tested for resistance to the obligate biotrophic oomycete Hyaloperonospora arabidopsidis Noco2 and the hemibiotrophic fungal pathogen Fusarium graminearum PH-1. MtDef4.2 directed to the extracellular space, but not to the vacuole or retained in the endoplasmic reticulum, conferred robust resistance to H. arabidopsidis. Siliques of transgenic Arabidopsis lines expressing either extracellularly or intracellularly targeted MtDef4.2 displayed low levels of resistance to F. graminearum, but accumulated substantially reduced levels of the mycotoxin deoxynivalenol. The data presented here suggest that extracellularly targeted MtDef4.2 is sufficient to provide strong resistance to the biotrophic oomycete, consistent with the extracellular lifestyle of this pathogen. However, the co-expression of extracellular and intracellular MtDef4.2 is probably required to achieve strong resistance to the hemibiotrophic pathogen F. graminearum which grows extracellularly and intracellularly. © 2012 THE AUTHORS. MOLECULAR PLANT PATHOLOGY © 2012 BSPP AND BLACKWELL PUBLISHING LTD.

  2. CRISPR-based gene replacement reveals evolutionarily conserved axon guidance functions of Drosophila Robo3 and Tribolium Robo2/3.

    Science.gov (United States)

    Evans, Timothy A

    2017-01-01

    Axon guidance receptors of the Roundabout (Robo) family regulate a number of axon guidance outcomes in bilaterian animals in addition to their canonical role in Slit-dependent midline repulsion. In the fruit fly Drosophila melanogaster, three Robo paralogs (Robo1, Robo2, and Robo3) each have specialized roles in regulating midline crossing and the formation of longitudinal axon pathways in the embryonic ventral nerve cord. The number of robo genes differs in other insects, and it is unknown whether the roles and/or signaling mechanisms of Drosophila Robos are shared in other insect species. To directly compare the axon guidance activities of Robo receptors in Drosophila and the flour beetle Tribolium castaneum, I have used a CRISPR/Cas9-based approach to replace Drosophila robo3 with Tribolium robo2/3. I show that when expressed from the robo3 locus in Drosophila embryos, Tribolium Robo2/3 (TcRobo2/3) protein is properly translated and localized to axons, where it reproduces the normal expression pattern of Drosophila Robo3. In embryos expressing TcRobo2/3 in place of robo3, two distinct subsets of longitudinal axons are guided properly to their normal positions in the intermediate neuropile, indicating that TcRobo2/3 can promote Robo3-dependent axon guidance decisions in developing Drosophila neurons. These observations suggest that the mechanism by which Drosophila Robo3 promotes longitudinal pathway formation is evolutionarily conserved in Tribolium, where it is performed by TcRobo2/3. The CRISPR/Cas9-based gene replacement approach described here can be applied to comparative evolutionary developmental studies of other Drosophila genes and their orthologs in other species.

  3. CRISPR-based gene replacement reveals evolutionarily conserved axon guidance functions of Drosophila Robo3 and Tribolium Robo2/3

    Directory of Open Access Journals (Sweden)

    Timothy A. Evans

    2017-06-01

    Full Text Available Abstract Background Axon guidance receptors of the Roundabout (Robo family regulate a number of axon guidance outcomes in bilaterian animals in addition to their canonical role in Slit-dependent midline repulsion. In the fruit fly Drosophila melanogaster, three Robo paralogs (Robo1, Robo2, and Robo3 each have specialized roles in regulating midline crossing and the formation of longitudinal axon pathways in the embryonic ventral nerve cord. The number of robo genes differs in other insects, and it is unknown whether the roles and/or signaling mechanisms of Drosophila Robos are shared in other insect species. To directly compare the axon guidance activities of Robo receptors in Drosophila and the flour beetle Tribolium castaneum, I have used a CRISPR/Cas9-based approach to replace Drosophila robo3 with Tribolium robo2/3. Results I show that when expressed from the robo3 locus in Drosophila embryos, Tribolium Robo2/3 (TcRobo2/3 protein is properly translated and localized to axons, where it reproduces the normal expression pattern of Drosophila Robo3. In embryos expressing TcRobo2/3 in place of robo3, two distinct subsets of longitudinal axons are guided properly to their normal positions in the intermediate neuropile, indicating that TcRobo2/3 can promote Robo3-dependent axon guidance decisions in developing Drosophila neurons. Conclusions These observations suggest that the mechanism by which Drosophila Robo3 promotes longitudinal pathway formation is evolutionarily conserved in Tribolium, where it is performed by TcRobo2/3. The CRISPR/Cas9-based gene replacement approach described here can be applied to comparative evolutionary developmental studies of other Drosophila genes and their orthologs in other species.

  4. Violation of an evolutionarily conserved immunoglobulin diversity gene sequence preference promotes production of dsDNA-specific IgG antibodies.

    Directory of Open Access Journals (Sweden)

    Aaron Silva-Sanchez

    Full Text Available Variability in the developing antibody repertoire is focused on the third complementarity determining region of the H chain (CDR-H3, which lies at the center of the antigen binding site where it often plays a decisive role in antigen binding. The power of VDJ recombination and N nucleotide addition has led to the common conception that the sequence of CDR-H3 is unrestricted in its variability and random in its composition. Under this view, the immune response is solely controlled by somatic positive and negative clonal selection mechanisms that act on individual B cells to promote production of protective antibodies and prevent the production of self-reactive antibodies. This concept of a repertoire of random antigen binding sites is inconsistent with the observation that diversity (DH gene segment sequence content by reading frame (RF is evolutionarily conserved, creating biases in the prevalence and distribution of individual amino acids in CDR-H3. For example, arginine, which is often found in the CDR-H3 of dsDNA binding autoantibodies, is under-represented in the commonly used DH RFs rearranged by deletion, but is a frequent component of rarely used inverted RF1 (iRF1, which is rearranged by inversion. To determine the effect of altering this germline bias in DH gene segment sequence on autoantibody production, we generated mice that by genetic manipulation are forced to utilize an iRF1 sequence encoding two arginines. Over a one year period we collected serial serum samples from these unimmunized, specific pathogen-free mice and found that more than one-fifth of them contained elevated levels of dsDNA-binding IgG, but not IgM; whereas mice with a wild type DH sequence did not. Thus, germline bias against the use of arginine enriched DH sequence helps to reduce the likelihood of producing self-reactive antibodies.

  5. IAA-Ala Resistant3, an evolutionarily conserved target of miR167, mediates Arabidopsis root architecture changes during high osmotic stress

    KAUST Repository

    Kinoshita, Natsuko

    2012-09-01

    The functions of microRNAs and their target mRNAs in Arabidopsis thaliana development have been widely documented; however, roles of stress-responsive microRNAs and their targets are not as well understood. Using small RNA deep sequencing and ATH1 microarrays to profile mRNAs, we identified IAA-Ala Resistant3 (IAR3) as a new target of miR167a. As expected, IAR3 mRNA was cleaved at the miR167a complementary site and under high osmotic stress miR167a levels decreased, whereas IAR3 mRNA levels increased. IAR3 hydrolyzes an inactive form of auxin (indole-3-acetic acid [IAA]-alanine) and releases bioactive auxin (IAA), a central phytohormone for root development. In contrast with the wild type, iar3 mutants accumulated reduced IAA levels and did not display high osmotic stress-induced root architecture changes. Transgenic plants expressing a cleavage-resistant form of IAR3 mRNA accumulated high levels of IAR3 mRNAs and showed increased lateral root development compared with transgenic plants expressing wild-type IAR3. Expression of an inducible noncoding RNA to sequester miR167a by target mimicry led to an increase in IAR3 mRNA levels, further confirming the inverse relationship between the two partners. Sequence comparison revealed the miR167 target site on IAR3 mRNA is conserved in evolutionarily distant plant species. Finally, we showed that IAR3 is required for drought tolerance. © 2012 American Society of Plant Biologists. All rights reserved.

  6. Peptides derived from evolutionarily conserved domains in Beclin-1 and Beclin-2 enhance the entry of lentiviral vectors into human cells.

    Science.gov (United States)

    Majdoul, Saliha; Cosette, Jeremie; Seye, Ababacar K; Bernard, Eric; Frin, Sophie; Holic, Nathalie; Chazal, Nathalie; Briant, Laurence; Espert, Lucile; Galy, Anne; Fenard, David

    2017-11-10

    Autophagy-related proteins such as Beclin-1 are involved in an array of complex processes, including antiviral responses, and may also modulate the efficiency of gene therapy viral vectors. The Tat-Beclin-1 (TB1) peptide has been reported as an autophagy-inducing factor inhibiting the replication of pathogens such as HIV, type 1 (HIV-1). However, autophagy-related proteins are also essential for the early steps of HIV-1 infection. Therefore, we examined the effects of the Beclin-1 evolutionarily conserved domain in TB1 on viral transduction and autophagy in single-round HIV infection or with nonreplicative HIV-1-derived lentiviral vectors. TB1 enhanced transduction with various pseudotypes but without inducing the autophagy process. TB1 augmented the transduction of human CD34+ hematopoietic stem/progenitor cells while maintaining their capacity to engraft in vivo into humanized mice. TB1 was as effective as other transduction additives and functioned by enhancing the adhesion and fusion of viral particles with target cells but not their aggregation. We also found that the N-terminal L1 loop was critical for TB1 transduction-enhancing activity. Interestingly, the Tat-Beclin-2 (TB2) peptide, derived from the human Beclin-2 protein, was even more potent than TB1 in promoting viral transduction and infection. Taken together, our findings suggest that the TB1 and TB2 peptides enhance the viral entry step. Tat-Beclin peptides therefore represent a new family of viral transduction enhancers for potential use in gene therapy. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  7. Prevalence of herpes simplex, Epstein Barr and human papilloma viruses in oral lichen planus.

    Science.gov (United States)

    Yildirim, Benay; Sengüven, Burcu; Demir, Cem

    2011-03-01

    The aim of the present study was to assess the prevalence of Herpes Simplex virus, Epstein Barr virus and Human Papilloma virus -16 in oral lichen planus cases and to evaluate whether any clinical variant, histopathological or demographic feature correlates with these viruses. The study was conducted on 65 cases. Viruses were detected immunohistochemically. We evaluated the histopathological and demographic features and statistically analysed correlation of these features with Herpes Simplex virus, Epstein Barr virus and Human Papilloma virus-16 positivity. Herpes Simplex virus was positive in six (9%) cases and this was not statistically significant. The number of Epstein Barr virus positive cases was 23 (35%) and it was statistically significant. Human Papilloma virus positivity in 14 cases (21%) was statistically significant. Except basal cell degeneration in Herpes Simplex virus positive cases, we did not observe any significant correlation between virus positivity and demographic or histopathological features. However an increased risk of Epstein Barr virus and Human Papilloma virus infection was noted in oral lichen planus cases. Taking into account the oncogenic potential of both viruses, oral lichen planus cases should be detected for the presence of these viruses.

  8. What's West Nile Virus?

    Science.gov (United States)

    ... OK for Kids? Your Teeth Heart Murmurs What's West Nile Virus? KidsHealth > For Kids > What's West Nile Virus? Print A A A en español ¿Qué es ... Virus del Nilo Occidental? What exactly is the West Nile virus? And why is everyone talking about mosquitoes ? Even ...

  9. New Hepatitis B Virus of Cranes That Has an Unexpected Broad Host Range

    Science.gov (United States)

    Prassolov, Alexej; Hohenberg, Heinz; Kalinina, Tatyana; Schneider, Carola; Cova, Lucyna; Krone, Oliver; Frölich, Kai; Will, Hans; Sirma, Hüseyin

    2003-01-01

    All hepadnaviruses known so far have a very limited host range, restricted to their natural hosts and a few closely related species. This is thought to be due mainly to sequence divergence in the large envelope protein and species-specific differences in host components essential for virus propagation. Here we report an infection of cranes with a novel hepadnavirus, designated CHBV, that has an unexpectedly broad host range and is only distantly evolutionarily related to avihepadnaviruses of related hosts. Direct DNA sequencing of amplified CHBV DNA as well a sequencing of cloned viral genomes revealed that CHBV is most closely related to, although distinct from, Ross' goose hepatitis B virus (RGHBV) and slightly less closely related to duck hepatitis B virus (DHBV). Phylogenetically, cranes are very distant from geese and ducks and are most closely related to herons and storks. Naturally occurring hepadnaviruses in the last two species are highly divergent in sequence from RGHBV and DHBV and do not infect ducks or do so only marginally. In contrast, CHBV from crane sera and recombinant CHBV produced from LMH cells infected primary duck hepatocytes almost as efficiently as DHBV did. This is the first report of a rather broad host range of an avihepadnavirus. Our data imply either usage of similar or identical entry pathways and receptors by DHBV and CHBV, unusual host and virus adaptation mechanisms, or divergent evolution of the host genomes and cellular components required for virus propagation. PMID:12525630

  10. Viruses infecting maize

    OpenAIRE

    Krstić, Branka; Stanković, Ivana; Bulajić, Aleksandra

    2014-01-01

    Over 40 plant viruses has been known to cause diseases of maize, but economically the most important yield looses, which in certain years can be total, are caused by viruses from Potyvirus genera, known to be aphid-transmitted in a non-persistant maner. The most important viruses, pathogens of maize, sugar cane and sorghum are considered to be Maize dwarf mosaic virus (MDMV), Sorghum mosaic virus (SrMV), Sugarcane mosaic virus (SCMV), and Johnsongrass mosaic virus (JGMV). In Serbia, the prese...

  11. Viruses in cancer treatment.

    Science.gov (United States)

    Alemany, R

    2013-03-01

    Soon after the discovery that viruses cause human disease, started the idea of using viruses to treat cancer. After the initial indiscriminate use, crude preparations of each novel virus in the early twentieth century, a second wave of virotherapy blossomed in the 60s with purified and selected viruses. Responses were rare and short-lived. Immune rejection of the oncolytic viruses was identified as the major problem and virotherapy was abandoned. During the past two decades virotherapy has re-emerged with engineered viruses, with a trend towards using them as tumor-debulking immunostimulatory agents combined with radio or chemotherapy. Currently, oncolytic Reovirus, Herpes, and Vaccinia virus are in late phase clinical trials. Despite the renewed hope, efficacy will require improving systemic tumor targeting, overcoming stroma barriers for virus spread, and selectively stimulating immune responses against tumor antigens but not against the virus. Virotherapy history, viruses, considerations for clinical trials, and hurdles are briefly overviewed.

  12. Impact of virus preparation quality on parvovirus filter performance.

    Science.gov (United States)

    Slocum, Ashley; Burnham, Mike; Genest, Paul; Venkiteshwaran, Adith; Chen, Dayue; Hughes, Joseph

    2013-01-01

    Virus-removal filtration technology is commonly used in the manufacturing process for biologics to remove potential viral contaminants. Virus-removal filters designed for retaining parvovirus, one of the smallest mammalian viruses, are considered an industry standard as they can effectively remove broad ranges of viruses. It has long been observed that the performance of virus filters can be influenced by virus preparations used in the laboratory scale studies (PDA, 2010). However, it remains unclear exactly what quality attributes of virus preparations are critical or indicative of virus filter performance as measured by effectiveness of virus removal and filter capacity consistency. In an attempt to better understand the relationship between virus preparation and virus filter performance, we have systematically prepared and analyzed different grades of parvovirus with different purity levels and compared their performance profiles on Viresolve® Pro parvovirus filters using four different molecules. Virus preparations used in the studies were characterized using various methods to measure DNA and protein content as well as the hydrodynamic diameter of virus particles. Our results indicate that the performance of Viresolve® Pro filters can be significantly impacted depending on the purity of the virus preparations used in the spike and recovery studies. More importantly, we have demonstrated that the purity of virus preparations is directly correlated to the measurable biochemical and biophysical properties of the virus preparations such as DNA and protein content and monodispersal status, thus making it possible to significantly improve the consistency and predictability of the virus filter performance during process step validations. Copyright © 2012 Wiley Periodicals, Inc.

  13. MENGENAL HANTA VIRUS

    Directory of Open Access Journals (Sweden)

    Tri Wijayanti

    2012-11-01

    Full Text Available Virus Hanta kurang infeksius, kecuali di dalam lingkungan tertentu. Lamanya waktu virus ini dapat bertahan di lingkungan, setelah keluar dari tubuh tikus tidaklah diketahui secara pasti. Tetapi percobaan laboratorium menunjukkan bahwa, daya infektifitasnya tidak dijumpai setelah dua hari pengeringan. Genus hanta virus terdiri dari 22 spesies virus, dapat menyebabkan hemorrhagic fever with renal syndrome (HFRS dan hanta virus pulmonary syndrome (HPS.

  14. Control of virus diseases in soybeans.

    Science.gov (United States)

    Hill, John H; Whitham, Steven A

    2014-01-01

    Soybean, one of the world's most important sources of animal feed and vegetable oil, can be infected by numerous viruses. However, only a small number of the viruses that can potentially infect soybean are considered as major economic problems to soybean production. Therefore, we consider management options available to control diseases caused by eight viruses that cause, or have the potential to cause, significant economic loss to producers. We summarize management tactics in use and suggest direction for the future. Clearly, the most important tactic is disease resistance. Several resistance genes are available for three of the eight viruses discussed. Other options include use of virus-free seed and avoidance of alternative virus hosts when planting. Attempts at arthropod vector control have generally not provided consistent disease management. In the future, disease management will be considerably enhanced by knowledge of the interaction between soybean and viral proteins. Identification of genes required for soybean defense may represent key regulatory hubs that will enhance or broaden the spectrum of basal resistance to viruses. It may be possible to create new recessive or dominant negative alleles of host proteins that do not support viral functions but perform normal cellular function. The future approach to virus control based on gene editing or exploiting allelic diversity points to necessary research into soybean-virus interactions. This will help to generate the knowledge needed for rational design of durable resistance that will maximize global production.

  15. Immunogenicity of a modified-live virus vaccine against bovine viral diarrhea virus types 1 and 2, infectious bovine rhinotracheitis virus, bovine parainfluenza-3 virus, and bovine respiratory syncytial virus when administered intranasally in young calves.

    Science.gov (United States)

    Xue, Wenzhi; Ellis, John; Mattick, Debra; Smith, Linda; Brady, Ryan; Trigo, Emilio

    2010-05-14

    The immunogenicity of an intranasally-administered modified-live virus (MLV) vaccine in 3-8 day old calves was evaluated against bovine viral diarrhea virus (BVDV) types 1 and 2, infectious bovine rhinotracheitis (IBR) virus, parainfluenza-3 (PI-3) virus and bovine respiratory syncytial virus (BRSV). Calves were intranasally vaccinated with a single dose of a multivalent MLV vaccine and were challenged with one of the respective viruses three to four weeks post-vaccination in five separate studies. There was significant sparing of diseases in calves intranasally vaccinated with the MLV vaccine, as indicated by significantly fewer clinical signs, lower rectal temperatures, reduced viral shedding, greater white blood cell and platelet counts, and less severe pulmonary lesions than control animals. This was the first MLV combination vaccine to demonstrate efficacy against BVDV types 1 and 2, IBR, PI-3 and BRSV in calves 3-8 days of age. Copyright 2010 Elsevier Ltd. All rights reserved.

  16. Epidemiology of virus infection and human cancer.

    Science.gov (United States)

    Chen, Chien-Jen; Hsu, Wan-Lun; Yang, Hwai-I; Lee, Mei-Hsuan; Chen, Hui-Chi; Chien, Yin-Chu; You, San-Lin

    2014-01-01

    The International Agency for Research on Cancer (IARC) has comprehensively assessed the human carcinogenicity of biological agents. Seven viruses including Epstein-Barr virus (EBV), hepatitis B virus (HBV), hepatitis C virus (HCV), Kaposi's sarcoma herpes virus (KSHV), human immunodeficiency virus, type-1 (HIV-1), human T cell lymphotrophic virus, type-1 (HTLV-1), and human papillomavirus (HPV) have been classified as Group 1 human carcinogens by IARC. The conclusions are based on the findings of epidemiological and mechanistic studies. EBV, HPV, HTLV-1, and KSHV are direct carcinogens; HBV and HCV are indirect carcinogens through chronic inflammation; HIV-1 is an indirect carcinogen through immune suppression. Some viruses may cause more than one cancer, while some cancers may be caused by more than one virus. However, only a proportion of persons infected by these oncogenic viruses will develop specific cancers. A series of studies have been carried out to assess the viral, host, and environmental cofactors of EBV-associated nasopharyngeal carcinoma, HBV/HCV-associated hepatocellular carcinoma, and HPV-associated cervical carcinoma. Persistent infection and high viral load are important risk predictors of these virus-caused cancers. Risk calculators incorporating host and viral factors have also been developed for the prediction of long-term risk of hepatocellular carcinoma. These risk calculators are useful for the triage and clinical management of infected patients. Both clinical trials and national programs of immunization or antiviral therapy have demonstrated a significant reduction in the incidence of cancers caused by HBV, HCV, and HPV. Future researches on gene-gene and gene-environment interaction of oncogenic viruses and human host are in urgent need.

  17. Influenza A virus infections in swine: pathogenesis and diagnosis.

    Science.gov (United States)

    Janke, B H

    2014-03-01

    Influenza has been recognized as a respiratory disease in swine since its first appearance concurrent with the 1918 "Spanish flu" human pandemic. All influenza viruses of significance in swine are type A, subtype H1N1, H1N2, or H3N2 viruses. Influenza viruses infect epithelial cells lining the surface of the respiratory tract, inducing prominent necrotizing bronchitis and bronchiolitis and variable interstitial pneumonia. Cell death is due to direct virus infection and to insult directed by leukocytes and cytokines of the innate immune system. The most virulent viruses consistently express the following characteristics of infection: (1) higher or more prolonged virus replication, (2) excessive cytokine induction, and (3) replication in the lower respiratory tract. Nearly all the viral proteins contribute to virulence. Pigs are susceptible to infection with both human and avian viruses, which often results in gene reassortment between these viruses and endemic swine viruses. The receptors on the epithelial cells lining the respiratory tract are major determinants of infection by influenza viruses from other hosts. The polymerases, especially PB2, also influence cross-species infection. Methods of diagnosis and characterization of influenza viruses that infect swine have improved over the years, driven both by the availability of new technologies and by the necessity of keeping up with changes in the virus. Testing of oral fluids from pigs for virus and antibody is a recent development that allows efficient sampling of large numbers of animals.

  18. To be or not to be alive: How recent discoveries challenge the traditional definitions of viruses and life.

    Science.gov (United States)

    Forterre, Patrick

    2016-10-01

    Three major discoveries have recently profoundly modified our perception of the viral world: molecular ecologists have shown that viral particles are more abundant than cells in natural environments; structural biologists have shown that some viruses from the three domains of life, Bacteria, Eukarya and Archaea, are evolutionarily related, and microbiologists have discovered giant viruses that rival with cells in terms of size and gene content. I discuss here the scientific and philosophical impact of these discoveries on the debates over the definition, nature (living or not), and origin of viruses. I suggest that viruses have often been considered non-living, because they are traditionally assimilated to their virions. However, the term virus describes a biological process and should integrate all aspects of the viral reproduction cycle. It is especially important to focus on the intracellular part of this cycle, the virocell, when viral information is actively expressed and reproduced, allowing the emergence of new viral genes. The virocell concept theoretically removes roadblocks that prevent defining viruses as living organisms. However, defining a "living organism" remains challenging, as indicated by the case of organelles that evolved from intracellular bacteria. To bypass this problem, I suggest considering that all biological entities that actively participate in the process of life are living. Copyright © 2016. Published by Elsevier Ltd.

  19. Viruses Infecting Reptiles

    Science.gov (United States)

    Marschang, Rachel E.

    2011-01-01

    A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch’s postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions. PMID:22163336

  20. Viruses Infecting Reptiles

    Directory of Open Access Journals (Sweden)

    Rachel E. Marschang

    2011-11-01

    Full Text Available A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch’s postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.

  1. Viruses infecting reptiles.

    Science.gov (United States)

    Marschang, Rachel E

    2011-11-01

    A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch's postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.

  2. Structural, biochemical, and phylogenetic analyses suggest that indole-3-acetic acid methyltransferase is an evolutionarily ancient member of the SABATH family.

    Science.gov (United States)

    Zhao, Nan; Ferrer, Jean-Luc; Ross, Jeannine; Guan, Ju; Yang, Yue; Pichersky, Eran; Noel, Joseph P; Chen, Feng

    2008-02-01

    The plant SABATH protein family encompasses a group of related small-molecule methyltransferases (MTs) that catalyze the S-adenosyl-L-methionine-dependent methylation of natural chemicals encompassing widely divergent structures. Indole-3-acetic acid (IAA) methyltransferase (IAMT) is a member of the SABATH family that modulates IAA homeostasis in plant tissues through methylation of IAA's free carboxyl group. The crystal structure of Arabidopsis (Arabidopsis thaliana) IAMT (AtIAMT1) was determined and refined to 2.75 A resolution. The overall tertiary and quaternary structures closely resemble the two-domain bilobed monomer and the dimeric arrangement, respectively, previously observed for the related salicylic acid carboxyl methyltransferase from Clarkia breweri (CbSAMT). To further our understanding of the biological function and evolution of SABATHs, especially of IAMT, we analyzed the SABATH gene family in the rice (Oryza sativa) genome. Forty-one OsSABATH genes were identified. Expression analysis showed that more than one-half of the OsSABATH genes were transcribed in one or multiple organs. The OsSABATH gene most similar to AtIAMT1 is OsSABATH4. Escherichia coli-expressed OsSABATH4 protein displayed the highest level of catalytic activity toward IAA and was therefore named OsIAMT1. OsIAMT1 exhibited kinetic properties similar to AtIAMT1 and poplar IAMT (PtIAMT1). Structural modeling of OsIAMT1 and PtIAMT1 using the experimentally determined structure of AtIAMT1 reported here as a template revealed conserved structural features of IAMTs within the active-site cavity that are divergent from functionally distinct members of the SABATH family, such as CbSAMT. Phylogenetic analysis revealed that IAMTs from Arabidopsis, rice, and poplar (Populus spp.) form a monophyletic group. Thus, structural, biochemical, and phylogenetic evidence supports the hypothesis that IAMT is an evolutionarily ancient member of the SABATH family likely to play a critical role in IAA

  3. Respiratory Syncytial Virus and Other Noninfluenza Respiratory Viruses in Older Adults.

    Science.gov (United States)

    Kodama, Fumihiro; Nace, David A; Jump, Robin L P

    2017-12-01

    Respiratory viral infections may cause serious complications for older adults, including residents of long-term care facilities (LTCFs). Although influenza is the most common cause of viral respiratory infections among older adults, several other respiratory viruses also cause significant morbidity and mortality, most notably respiratory syncytial virus. Other noninfluenza respiratory viral pathogens include human metapneumovirus, parainfluenza virus, rhinovirus, coronavirus, and adenovirus. All of these may cause outbreaks among LTCF residents. Recently developed rapid diagnostic molecular tests may clarify the epidemiology of these viruses and have potential, through early identification, to limit the severity of outbreaks among older adults living in LTCFs. Published by Elsevier Inc.

  4. Broad virus resistance in transgenic plants

    NARCIS (Netherlands)

    Prins, M.W.

    2003-01-01

    Viruses are significant threats to agricultural crops worldwide and the limited sources of natural resistance warrant the development of novel resistance sources. Several methods of transgenic protection have been successfully applied, including protein- and RNA-mediated approaches. Increased

  5. Dengue Virus Coinfection in Human Immunodeficiency Virus-1-Infected Patients on the West Coast of Mexico.

    Science.gov (United States)

    Espinoza-Gómez, Francisco; Delgado-Enciso, Iván; Valle-Reyes, Salvador; Ochoa-Jiménez, Rodolfo; Arechiga-Ramírez, Conrado; Gámez-Arroyo, José L; Vázquez-Campuzano, Roberto; Guzmán-Bracho, Carmen; Vásquez, Clemente; López-Lemus, Uriel A

    2017-09-01

    Dengue virus infection in human immunodeficiency virus (HIV)-positive patients is not well studied. Previous reports suggest a transitory inhibition of the HIV-1 viral load, as well as a benign clinical progression of dengue. The follow-up of six HIV-1-infected patients, diagnosed and hospitalized with dengue virus infection in the State of Colima, Mexico, was carried out to analyze the progression of this viral coinfection. The presence of dengue virus serotype 1 was confirmed through molecular tests. No severe complications were observed in any of the patients during dengue virus infection. Significant alteration of the HIV-1 viral loads was not observed during dengue virus infection and 6 months after coinfection. Further studies are required to understand the pathology, as well as the clinical course, of these viral coinfections.

  6. Designing herpes viruses as oncolytics

    Science.gov (United States)

    Peters, Cole; Rabkin, Samuel D

    2015-01-01

    Oncolytic herpes simplex virus (oHSV) was one of the first genetically-engineered oncolytic viruses. Because HSV is a natural human pathogen that can cause serious disease, it is incumbent that it can be genetically-engineered or significantly attenuated for safety. Here, we present a detailed explanation of the functions of HSV-1 genes frequently mutated to endow oncolytic activity. These genes are nonessential for growth in tissue culture cells but are important for growth in postmitotic cells, interfering with intrinsic antiviral and innate immune responses or causing pathology, functions dispensable for replication in cancer cells. Understanding the function of these genes leads to informed creation of new oHSVs with better therapeutic efficacy. Virus infection and replication can also be directed to cancer cells through tumor-selective receptor binding and transcriptional- or post-transcriptional miRNA-targeting, respectively. In addition to the direct effects of oHSV on infected cancer cells and tumors, oHSV can be “armed” with transgenes that are: reporters, to track virus replication and spread; cytotoxic, to kill uninfected tumor cells; immune modulatory, to stimulate antitumor immunity; or tumor microenvironment altering, to enhance virus spread or to inhibit tumor growth. In addition to HSV-1, other alphaherpesviruses are also discussed for their oncolytic activity. PMID:26462293

  7. Immunological responses against human papilloma virus and human papilloma virus induced laryngeal cancer.

    Science.gov (United States)

    Chitose, Shun-ichi; Sakazaki, T; Ono, T; Kurita, T; Mihashi, H; Nakashima, T

    2010-06-01

    This study aimed to clarify the local immune status in the larynx in the presence of infection or carcinogenesis associated with human papilloma virus. Cytological samples (for human papilloma virus detection) and laryngeal secretions (for immunoglobulin assessment) were obtained from 31 patients with laryngeal disease, during microscopic laryngeal surgery. On histological examination, 12 patients had squamous cell carcinoma, four had laryngeal papilloma and 15 had other benign laryngeal disease. Cytological samples were tested for human papilloma virus DNA using the Hybrid Capture 2 assay. High risk human papilloma virus DNA was detected in 25 per cent of patients (three of 12) with laryngeal cancer. Low risk human papilloma virus DNA was detected only in three laryngeal papilloma patients. The mean laryngeal secretion concentrations of immunoglobulins M, G and A and secretory immunoglobulin A in human papilloma virus DNA positive patients were more than twice those in human papilloma virus DNA negative patients. A statistically significant difference was observed between the secretory immunoglobulin A concentrations in the two groups. Patients with laryngeal cancer had higher laryngeal secretion concentrations of each immunoglobulin type, compared with patients with benign laryngeal disease. The study assessed the mean laryngeal secretion concentrations of each immunoglobulin type in the 12 laryngeal cancer patients, comparing human papilloma virus DNA positive patients (n = 3) and human papilloma virus DNA negative patients (n = 9); the mean concentrations of immunoglobulins M, G and A and secretory immunoglobulin A tended to be greater in human papilloma virus DNA positive cancer patients, compared with human papilloma virus DNA negative cancer patients. These results suggest that the local laryngeal immune response is activated by infection or carcinogenesis due to human papilloma virus. The findings strongly suggest that secretory IgA has inhibitory activity

  8. Testing for Human Immunodeficiency Virus

    Science.gov (United States)

    ... education Fact Sheet PFS005: Testing for Human Immunodeficiency Virus AUGUST 2015 • Reasons for Getting Tested • Who Should ... For More Information • Glossary Testing for Human Immunodeficiency Virus Human immunodeficiency virus (HIV) is the virus that ...

  9. Viruses in cancers among the immunosuppressed.

    Science.gov (United States)

    Arroyo Mühr, Laila Sara; Bzhalava, Zurab; Hortlund, Maria; Lagheden, Camilla; Nordqvist Kleppe, Sara; Bzhalava, Davit; Hultin, Emilie; Dillner, Joakim

    2017-12-15

    Most cancer forms known to be caused by viruses are increased among the immunosuppressed, but several cancer forms without established viral etiology are also increased, notably nonmelanoma skin carcinoma (NMSC). We followed all 13,429 solid organ transplantation patients in Sweden for cancer occurrence after transplantation. We requested these tumor specimens and sequenced the first 89 specimens received (62 NMSCs, 27 other cancers). The sequences were analyzed for viruses based on two bioinformatics algorithms (paracel-blast (sensitive for detection of known viruses) and hidden Markov model (HMM; sensitive for distantly related viruses)). Among the 62 NMSCs, the virus family detected in the largest proportion of specimens was Mimiviridae (9/62 NMSCs). The majority of the virus-related reads belonged to Papillomaviridae. The HMM analysis identified 86 additional previously not described viral contigs related to 11 virus families, with reads related to Mimiviridae being the most common (detected in 28/62 NMSCs) with the most prevalent contig (Mimivirus SE906, 1937 bp) detected in 17/62 NMSCs. Among the 27 other cancers, viral sequences were detected in only 5 specimens by blast analysis, compared to in all 27 specimens by HMM (Mimiviridae, Poxviridae, Phycodnaviridae and virus-related sequences yet unclassified to any family). 99% of the virus reads belonged to a single previously not described sequence (Mimivirus SE996, 911 bp). A multitude of viruses is readily detectable in specimens with cancers occurring among the immunosuppressed, with sequences related to Mimiviridae being the most prevalent. Further research would be needed to elucidate the biological significance of the viruses. © 2017 UICC.

  10. Marine Viruses that infect Eukaryotic Microalgae.

    Science.gov (United States)

    Kimura, Kei; Tomaru, Yuji

    2015-01-01

    Marine microalgae, in general, explain large amount of the primary productions on the planet. Their huge biomass through photosynthetic activities is significant to understand the global geochemical cycles. Many researchers are, therefore, focused on studies of marine microalgae, i.e. phytoplankton. Since the first report of high abundance of viruses in the sea at late 1980's, the marine viruses have recognized as an important decreasing factor of its host populations. They seem to be composed of diverse viruses infectious to different organism groups; most of them are considered to be phages infectious to prokaryotes, and viruses infecting microalgae might be ranked in second level. Over the last quarter of a century, the knowledge on marine microalgal viruses has been accumulated in many aspects. Until today, ca. 40 species of marine microalgal viruses have been discovered, including dsDNA, ssDNA, dsRNA and ssRNA viruses. Their features are unique and comprise new ideas and discoveries, indicating that the marine microalgal virus research is still an intriguing unexplored field. In this review, we summarize their basic biology and ecology, and discuss how and what we should research in this area for further progress.

  11. VIRUS FAMILIES – contd

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. VIRUS FAMILIES – contd. Minus strand RNA viruses. Rhabdovirus e.g. rabies. Paramyxovirus e.g. measles, mumps. Orthomyxovirus e.g. influenza. Retroviruses. RSV, HTLV, MMTV, HIV. Notes:

  12. Zika Virus Fact Sheet

    Science.gov (United States)

    ... Fact files Questions & answers Features Multimedia Contacts Zika virus Fact sheet Updated 6 September 2016 Key facts ... last for 2-7 days. Complications of Zika virus disease Based on a systematic review of the ...

  13. Hepatitis virus panel

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003558.htm Hepatitis virus panel To use the sharing features on this page, please enable JavaScript. The hepatitis virus panel is a series of blood tests used ...

  14. Virus Assembly and Maturation

    Science.gov (United States)

    Johnson, John E.

    2004-03-01

    We use two techniques to look at three-dimensional virus structure: electron cryomicroscopy (cryoEM) and X-ray crystallography. Figure 1 is a gallery of virus particles whose structures Timothy Baker, one of my former colleagues at Purdue University, used cryoEM to determine. It illustrates the variety of sizes of icosahedral virus particles. The largest virus particle on this slide is the Herpes simplex virus, around 1200Å in diameter; the smallest we examined was around 250Å in diameter. Viruses bear their genomic information either as positive-sense DNA and RNA, double-strand DNA, double-strand RNA, or negative-strand RNA. Viruses utilize the various structure and function "tactics" seen throughout cell biology to replicate at high levels. Many of the biological principles that we consider general were in fact discovered in the context of viruses ...

  15. Respiratory syncytial virus (RSV)

    Science.gov (United States)

    RSV; Palivizumab; Respiratory syncytial virus immune globulin; Bronchiolitis - RSV ... Crowe JE. Respiratory syncytial virus. In: Kliegman RM, Stanton BF, St Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ...

  16. Zika Virus Fact Sheet

    Science.gov (United States)

    ... sheets Fact files Questions & answers Features Multimedia Contacts Zika virus Fact sheet Updated 6 September 2016 Key facts ... and last for 2-7 days. Complications of Zika virus disease Based on a systematic review of the ...

  17. Zika Virus - Multiple Languages

    Science.gov (United States)

    ... Are Here: Home → Multiple Languages → All Health Topics → Zika Virus URL of this page: https://medlineplus.gov/languages/ ... V W XYZ List of All Topics All Zika Virus - Multiple Languages To use the sharing features on ...

  18. Viruses and Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lawson, James S., E-mail: james.lawson@unsw.edu.au; Heng, Benjamin [School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney (Australia)

    2010-04-30

    Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix.

  19. West Nile Virus

    Science.gov (United States)

    West Nile virus (WNV) is an infectious disease that first appeared in the United States in 1999. Infected mosquitoes ... and usually go away on their own. If West Nile virus enters the brain, however, it can be life- ...

  20. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... My ACOG ACOG Departments Donate Shop Career Connection Home Clinical Guidance & Publications Practice Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and Pregnancy Page Navigation ▼ ...

  1. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Resources & Publications Practice Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and Pregnancy Page Navigation ▼ ACOG Pregnancy ...

  2. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... My ACOG ACOG Departments Donate Shop Career Connection Home Resources & Publications Practice Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and Pregnancy Page Navigation ▼ ...

  3. Human Parainfluenza Viruses

    Science.gov (United States)

    ... Search Form Controls Cancel Submit Search The CDC Human Parainfluenza Viruses (HPIVs) Note: Javascript is disabled or ... CDC.gov . Recommend on Facebook Tweet Share Compartir Human parainfluenza viruses (HPIVs) commonly cause respiratory illnesses in ...

  4. Different virus-derived siRNAs profiles between leaves and fruits in Cucumber green mottle mosaic virus-infected Lagenaria siceraria

    Directory of Open Access Journals (Sweden)

    Junmin Li

    2016-11-01

    Full Text Available RNA silencing is an evolutionarily conserved antiviral mechanism, through which virus-derived small interfering RNAs (vsiRNAs playing roles in host antiviral defence are produced in virus-infected plant. Deep sequencing technology has revolutionized the study on the interaction between virus and plant host through the analysis of vsiRNAs profile. However, comparison of vsiRNA profiles in different tissues from a same host plant has been rarely reported. In this study, the profiles of virus-derived small interfering RNAs (vsiRNAs from leaves and fruits of Lagenaria siceraria plants infected with Cucumber green mottle mosaic virus (CGMMV were comprehensively characterized and compared. Many more vsiRNAs were present in infected leaves than in fruits. vsiRNAs from both leaves and fruits were mostly 21- and 22-nt in size as previously described in other virus-infected plants. Interestingly, vsiRNAs were predominantly produced from the viral positive strand RNAs in infected leaves, whereas in infected fruits they were derived equally from the positive and negative strands. Many leaf-specific positive vsiRNAs with lengths of 21-nt (2,058 or 22-nt (3,996 were identified but only six (21-nt and one (22-nt positive vsiRNAs were found to be specific to fruits. vsiRNAs hotspots were only present in the 5’-terminal and 3’-terminal of viral positive strand in fruits, while multiple hotspots were identified in leaves. Differences in GC content and 5'-terminal nucleotide of vsiRNAs were also observed in the two organs. To our knowledge, this provides the first high-resolution comparison of vsiRNA profiles between different tissues of the same host plant.

  5. [Bats and Viruses: complex relationships].

    Science.gov (United States)

    Rodhain, F

    2015-10-01

    With more than 1 200 species, bats and flying foxes (Order Chiroptera) constitute the most important and diverse order of Mammals after Rodents. Many species of bats are insectivorous while others are frugivorous and few of them are hematophagous. Some of these animals fly during the night, others are crepuscular or diurnal. Some fly long distances during seasonal migrations. Many species are colonial cave-dwelling, living in a rather small home range while others are relatively solitary. However, in spite of the importance of bats for terrestrial biotic communities and ecosystem ecology, the diversity in their biology and lifestyles remain poorly known and underappreciated. More than sixty viruses have been detected or isolated in bats; these animals are therefore involved in the natural cycles of many of them. This is the case, for instance, of rabies virus and other Lyssavirus (Family Rhabdoviridae), Nipah and Hendra viruses (Paramyxoviridae), Ebola and Marburg viruses (Filoviridae), SARS-CoV and MERS-CoV (Coronaviridae). For these zoonotic viruses, a number of bat species are considered as important reservoir hosts, efficient disseminators or even directly responsible of the transmission. Some of these bat-borne viruses cause highly pathogenic diseases while others are of potential significance for humans and domestic or wild animals; so, bats are an important risk in human and animal public health. Moreover, some groups of viruses developed through different phylogenetic mechanisms of coevolution between viruses and bats. The fact that most of these viral infections are asymptomatic in bats has been observed since a long time but the mechanisms of the viral persistence are not clearly understood. The various bioecology of the different bat populations allows exchange of virus between migrating and non-migrating conspecific species. For a better understanding of the role of bats in the circulation of these viral zoonoses, epidemiologists must pay attention to

  6. [Mumps vaccine virus transmission].

    Science.gov (United States)

    Otrashevskaia, E V; Kulak, M V; Otrashevskaia, A V; Karpov, I A; Fisenko, E G; Ignat'ev, G M

    2013-01-01

    In this work we report the mumps vaccine virus shedding based on the laboratory confirmed cases of the mumps virus (MuV) infection. The likely epidemiological sources of the transmitted mumps virus were children who were recently vaccinated with the mumps vaccine containing Leningrad-Zagreb or Leningrad-3 MuV. The etiology of the described cases of the horizontal transmission of both mumps vaccine viruses was confirmed by PCR with the sequential restriction analysis.

  7. Determinants of host species range in plant viruses.

    Science.gov (United States)

    Moury, Benoît; Fabre, Frédéric; Hébrard, Eugénie; Froissart, Rémy

    2017-04-01

    Prediction of pathogen emergence is an important field of research, both in human health and in agronomy. Most studies of pathogen emergence have focused on the ecological or anthropic factors involved rather than on the role of intrinsic pathogen properties. The capacity of pathogens to infect a large set of host species, i.e. to possess a large host range breadth (HRB), is tightly linked to their emergence propensity. Using an extensive plant virus database, we found that four traits related to virus genome or transmission properties were strongly and robustly linked to virus HRB. Broader host ranges were observed for viruses with single-stranded genomes, those with three genome segments and nematode-transmitted viruses. Also, two contrasted groups of seed-transmitted viruses were evidenced. Those with a single-stranded genome had larger HRB than non-seed-transmitted viruses, whereas those with a double-stranded genome (almost exclusively RNA) had an extremely small HRB. From the plant side, the family taxonomic rank appeared as a critical threshold for virus host range, with a highly significant increase in barriers to infection between plant families. Accordingly, the plant-virus infectivity matrix shows a dual structure pattern: a modular pattern mainly due to viruses specialized to infect plants of a given family and a nested pattern due to generalist viruses. These results contribute to a better prediction of virus host jumps and emergence risks.

  8. Protection against Influenza Virus Infection of Mice Fed Bifidobacterium breve YIT4064

    OpenAIRE

    Yasui, Hisako; Kiyoshima, Junko; Hori, Tetuji; SHIDA, Kan

    1999-01-01

    Mice fed Bifidobacterium breve YIT4064 and immunized orally with influenza virus were more strongly protected against influenza virus infection of the lower respiratory tract than ones immunized with influenza virus only. The number of mice with enhanced anti-influenza virus immunoglobulin G (IgG) in serum upon oral administration of B. breve YIT4064 and oral immunization with influenza virus was significantly greater than that upon oral immunization with influenza...

  9. Nairobi sheep disease virus/Ganjam virus.

    Science.gov (United States)

    M D, Baron; B, Holzer

    2015-08-01

    Nairobi sheep disease virus (NSDV) is a tick-borne virus which causes a severe disease in sheep and goats, and has been responsible for several outbreaks of disease in East Africa. The virus is also found in the Indian subcontinent, where it is known as Ganjam virus. The virus only spreads through the feeding of competent infected ticks, and is therefore limited in its geographic distribution by the distribution of those ticks, Rhipicephalus appendiculata in Africa and Haemaphysalis intermedia in India. Animals bred in endemic areas do not normally develop disease, and the impact is therefore primarily on animals being moved for trade or breeding purposes. The disease caused by NSDV has similarities to several other ruminant diseases, and laboratory diagnosis is necessary for confirmation. There are published methods for diagnosis based on polymerase chain reaction, for virus growth in cell culture and for other simple diagnostic tests, though none has been commercialised. There is no established vaccine against NSDV, although cell-culture attenuated strains have been developed which show promise and could be put into field trials if it were deemed necessary. The virus is closely related to Crimean-Congo haemorrhagic fever virus, and studies on NSDV may therefore be useful in understanding this important human pathogen.

  10. West nile virus-induced activation of mammalian target of rapamycin complex 1 supports viral growth and viral protein expression.

    Science.gov (United States)

    Shives, Katherine D; Beatman, Erica L; Chamanian, Mastooreh; O'Brien, Caitlin; Hobson-Peters, Jody; Beckham, J David

    2014-08-01

    Since its introduction in New York City, NY, in 1999, West Nile virus (WNV) has spread to all 48 contiguous states of the United States and is now the leading cause of epidemic encephalitis in North America. As a member of the family Flaviviridae, WNV is part of a group of clinically important human pathogens, including dengue virus and Japanese encephalitis virus. The members of this family of positive-sense, single-stranded RNA viruses have limited coding capacity and are therefore obligated to co-opt a significant amount of cellular factors to translate their genomes effectively. Our previous work has shown that WNV growth was independent of macroautophagy activation, but the role of the evolutionarily conserved mammalian target of rapamycin (mTOR) pathway during WNV infection was not well understood. mTOR is a serine/threonine kinase that acts as a central cellular censor of nutrient status and exercises control of vital anabolic and catabolic cellular responses such as protein synthesis and autophagy, respectively. We now show that WNV activates mTOR and cognate downstream activators of cap-dependent protein synthesis at early time points postinfection and that pharmacologic inhibition of mTOR (KU0063794) significantly reduced WNV growth. We used an inducible Raptor and Rictor knockout mouse embryonic fibroblast (MEF) system to further define the role of mTOR complexes 1 and 2 in WNV growth and viral protein synthesis. Following inducible genetic knockout of the major mTOR cofactors raptor (TOR complex 1 [TORC1]) and rictor (TORC2), we now show that TORC1 supports flavivirus protein synthesis via cap-dependent protein synthesis pathways and supports subsequent WNV growth. Since its introduction in New York City, NY, in 1999, West Nile virus (WNV) has spread to all 48 contiguous states in the United States and is now the leading cause of epidemic encephalitis in North America. Currently, the mechanism by which flaviviruses such as WNV translate their genomes in

  11. Surveillance of respiratory viruses.

    African Journals Online (AJOL)

    Surveillance of respiratory viruses. A 10-year laboratory-based study. J. M. McAnerney, S. Johnson, B. D. Schoub. Respiratory virus isolates made at the National Institute for. Virology from 1982 to 1991 were studied. An active virus surveillance programme, 'viral watch', which recruits throat swab specimens from a network ...

  12. Characteristic of pandemic virus

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Characteristic of pandemic virus. The virus was highly transmissible. Risk of hospitalization was 2X and risk of death was about 11X more in comparison to seasonal influenza. Virus continues to be susceptible to Osaltamivir, the only drug available. Vaccines are available but ...

  13. ICTV Virus Taxonomy Profile

    DEFF Research Database (Denmark)

    Simmonds, Peter; Becher, Paul; Bukh, Jens

    2017-01-01

    borne, and many are important human and veterinary pathogens (e.g. yellow fever virus, dengue virus). This is a summary of the current International Committee on Taxonomy of Viruses (ICTV) report on the taxonomy of the Flaviviridae, which is available at www.ictv.global/report/flaviviridae....

  14. Computer Virus Protection

    Science.gov (United States)

    Rajala, Judith B.

    2004-01-01

    A computer virus is a program--a piece of executable code--that has the unique ability to replicate. Like biological viruses, computer viruses can spread quickly and are often difficult to eradicate. They can attach themselves to just about any type of file, and are spread by replicating and being sent from one individual to another. Simply having…

  15. Respiratory syncytial virus bronchiolitis.

    Science.gov (United States)

    Jeng, M J; Lemen, R J

    1997-03-01

    Respiratory syncytial virus (RSV) bronchiolitis is associated with the clinical signs and symptoms of small airway obstruction. A major public health problem throughout the world, this condition is responsible for significant morbidity and mortality. Management is primarily preventive, through strict hand washing, avoidance of exposure during the respiratory illness season and intravenously administered prophylactic anti-RSV Immune globulin, especially in selected small infants with underlying cardiopulmonary disease. Supportive measures, including fluid hydration, good nutrition, aerosolized bronchodilators and steroids, may be helpful. Ribavirin may be useful in severely ill children or those with underlying cardiopulmonary disease. A significant number of patients have recurrent episodes of bronchiolitis and wheezing, and may develop asthma later in life. Avoidance of exposure to tobacco smoke, cold air and air pollutants is also beneficial to long-term recovery from RSV bronchiolitis. A number of vaccines to prevent this infection are currently being studied.

  16. Virus variation resources at the National Center for Biotechnology Information: dengue virus

    Directory of Open Access Journals (Sweden)

    Rozanov Michael

    2009-04-01

    Full Text Available Abstract Background There is an increasing number of complete and incomplete virus genome sequences available in public databases. This large body of sequence data harbors information about epidemiology, phylogeny, and virulence. Several specialized databases, such as the NCBI Influenza Virus Resource or the Los Alamos HIV database, offer sophisticated query interfaces along with integrated exploratory data analysis tools for individual virus species to facilitate extracting this information. Thus far, there has not been a comprehensive database for dengue virus, a significant public health threat. Results We have created an integrated web resource for dengue virus. The technology developed for the NCBI Influenza Virus Resource has been extended to process non-segmented dengue virus genomes. In order to allow efficient processing of the dengue genome, which is large in comparison with individual influenza segments, we developed an offline pre-alignment procedure which generates a multiple sequence alignment of all dengue sequences. The pre-calculated alignment is then used to rapidly create alignments of sequence subsets in response to user queries. This improvement in technology will also facilitate the incorporation of additional virus species in the future. The set of virus-specific databases at NCBI, which will be referred to as Virus Variation Resources (VVR, allow users to build complex queries against virus-specific databases and then apply exploratory data analysis tools to the results. The metadata is automatically collected where possible, and extended with data extracted from the literature. Conclusion The NCBI Dengue Virus Resource integrates dengue sequence information with relevant metadata (sample collection time and location, disease severity, serotype, sequenced genome region and facilitates retrieval and preliminary analysis of dengue sequences using integrated web analysis and visualization tools.

  17. Current status of a hepatitis C vaccine: encouraging results but significant challenges ahead

    DEFF Research Database (Denmark)

    Mikkelsen, Marianne; Bukh, Jens

    2007-01-01

    . Thus, an HCV vaccine that could significantly lower the chronicity rate would have a major impact on the disease burden. Unfortunately, HCV is a highly mutable virus, and escape mutations can undermine vaccine-induced virus-specific immunity. Also, HCV exists as multiple genotypes, and so genotype...

  18. Fever versus Fever: the role of host and vector susceptibility and interspecific competition in shaping the current and future distributions of the sylvatic cycles of dengue virus and yellow fever virus

    Science.gov (United States)

    Hanley, Kathryn A.; Monath, Thomas P.; Weaver, Scott C.; Rossi, Shannan L.; Richman, Rebecca L.; Vasilakis, Nikos

    2013-01-01

    Two different species of flaviviruses, dengue virus (DENV) and yellow fever virus (YFV), that originated in sylvatic cycles maintained in non-human primates and forest-dwelling mosquitoes have emerged repeatedly into sustained human-to-human transmission by Aedes aegypti mosquitoes. Sylvatic cycles of both viruses remain active, and where the two viruses overlap in West Africa they utilize similar suites of monkeys and Aedes mosquitoes. These extensive similarities render the differences in the biogeography and epidemiology of the two viruses all the more striking. First, the sylvatic cycle of YFV originated in Africa and was introduced into the New World, probably as a result of the slave trade, but is absent in Asia; in contrast, sylvatic DENV likely originated in Asia and has spread to Africa but not to the New World. Second, while sylvatic YFV can emerge into extensive urban outbreaks in humans, these invariably die out, whereas four different types of DENV have established human transmission cycles that are ecologically and evolutionarily distinct from their sylvatic ancestors. Finally, transmission of YFV among humans has been documented only in Africa and the Americas, whereas DENV is transmitted among humans across most of the range of competent Aedes vectors, which in the last decade has included every continent save Antarctica. This review summarizes current understanding of sylvatic transmission cycles of YFV and DENV, considers possible explanations for their disjunct distributions, and speculates on the potential consequences of future establishment of a sylvatic cycle of DENV in the Americas. PMID:23523817

  19. Herpes viruses and human papilloma virus in nasal polyposis and controls.

    Science.gov (United States)

    Ioannidis, Dimitrios; Lachanas, Vasileios A; Florou, Zoe; Bizakis, John G; Petinaki, Efthymia; Skoulakis, Charalampos E

    2015-01-01

    Chronic rhinosinusitis with nasal polyps is a multifactorial disease entity with an unclear pathogenesis. Contradictory data exist in the literature on the potential implication of viral elements in adult patients with chronic rhinosinusitis. To compare the prevalence of human herpes viruses (1-6) and Human Papilloma Virus in adult patients with chronic rhinosinusitis with nasal polyps and healthy controls. Viral DNA presence was evaluated by real-time polymerase chain reaction application to nasal polyps specimens from 91 chronic rhinosinusitis with nasal polyps patients and nasal turbinate mucosa from 38 healthy controls. Epstein-Barr virus positivity was higher in nasal polyps (24/91; 26.4%) versus controls (4/38; 10.5%), but the difference did not reach significance (p=0.06). Human herpes virus-6 positivity was lower in nasal polyps (13/91; 14.29%) versus controls (10/38; 26.32%, p=0.13). In chronic rhinosinusitis with nasal polyps group, 1 sample was herpes simplex virus-1-positive (1/91; 1.1%), and another was cytomegalovirus-positive (1/91; 1.1%), versus none in controls. No sample was positive for herpes simplex virus-2, varicella-zoster virus, high-risk-human papilloma viruses (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59) and low-risk-human papilloma viruses (6, 11). Differences in Epstein-Barr virus and human herpes virus-6 positivity among patients with chronic rhinosinusitis with nasal polyps and healthy controls are not statistically significant, weakening the likelihood of their implication in chronic rhinosinusitis with nasal polyps pathogenesis. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  20. Herpes viruses and human papilloma virus in nasal polyposis and controls

    Directory of Open Access Journals (Sweden)

    Dimitrios Ioannidis

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: Chronic rhinosinusitis with nasal polyps is a multifactorial disease entity with an unclear pathogenesis. Contradictory data exist in the literature on the potential implication of viral elements in adult patients with chronic rhinosinusitis. OBJECTIVE: To compare the prevalence of human herpes viruses (1-6 and Human Papilloma Virus in adult patients with chronic rhinosinusitis with nasal polyps and healthy controls. METHODS: Viral DNA presence was evaluated by real-time polymerase chain reaction application to nasal polyps specimens from 91 chronic rhinosinusitis with nasal polyps patients and nasal turbinate mucosa from 38 healthy controls. RESULTS: Epstein-Barr virus positivity was higher in nasal polyps (24/91; 26.4% versus controls (4/38; 10.5%, but the difference did not reach significance (p = 0.06. Human herpes virus-6 positivity was lower in nasal polyps (13/91; 14.29% versus controls (10/38; 26.32%,p = 0.13. In chronic rhinosinusitis with nasal polyps group, 1 sample was herpes simplex virus-1-positive (1/91; 1.1%, and another was cytomegalovirus-positive (1/91; 1.1%, versus none in controls. No sample was positive for herpes simplex virus-2, varicella-zoster virus, high-risk-human papilloma viruses (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and low-risk-human papilloma viruses (6, 11. CONCLUSION: Differences in Epstein-Barr virus and human herpes virus-6 positivity among patients with chronic rhinosinusitis with nasal polyps and healthy controls are not statistically significant, weakening the likelihood of their implication in chronic rhinosinusitis with nasal polyps pathogenesis.

  1. Ebola virus disease: history, epidemiology and outbreaks.

    Science.gov (United States)

    Weyer, Jacqueline; Grobbelaar, Antoinette; Blumberg, Lucille

    2015-05-01

    Over the past 40 years, sporadic Ebola virus disease (EVD) outbreaks have occurred mostly in the central African region. In March 2014, an outbreak of EVD was recognized in Guinea which would become the most significant outbreak of haemorrhagic fever in Africa to date. The outbreak started in Guinea and rapidly spread to Liberia and Sierra Leone, claiming thousands of lives. Many questions still remain regarding the ecology of Ebola viruses, but it is believed that contact with infected bushmeat is an important risk factor for initial spill over of the virus into the human population. At present, there is still no registered prophylaxis or curative biologicals against EVD.

  2. Blueberry (Vaccinium corymbosum)-Virus Diseases

    Science.gov (United States)

    At least six viruses have been found in highbush blueberry plantings in the Pacific Northwest: Blueberry mosaic virus, Blueberry red ringspot virus, Blueberry scorch virus, Blueberry shock virus, Tobacco ringspot virus, and Tomato ringspot virus. Six other virus and virus-like diseases of highbush b...

  3. Quantitative estimation of Nipah virus replication kinetics in vitro

    Directory of Open Access Journals (Sweden)

    Hassan Sharifah

    2006-06-01

    Full Text Available Abstract Background Nipah virus is a zoonotic virus isolated from an outbreak in Malaysia in 1998. The virus causes infections in humans, pigs, and several other domestic animals. It has also been isolated from fruit bats. The pathogenesis of Nipah virus infection is still not well described. In the present study, Nipah virus replication kinetics were estimated from infection of African green monkey kidney cells (Vero using the one-step SYBR® Green I-based quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR assay. Results The qRT-PCR had a dynamic range of at least seven orders of magnitude and can detect Nipah virus from as low as one PFU/μL. Following initiation of infection, it was estimated that Nipah virus RNA doubles at every ~40 minutes and attained peak intracellular virus RNA level of ~8.4 log PFU/μL at about 32 hours post-infection (PI. Significant extracellular Nipah virus RNA release occurred only after 8 hours PI and the level peaked at ~7.9 log PFU/μL at 64 hours PI. The estimated rate of Nipah virus RNA released into the cell culture medium was ~0.07 log PFU/μL per hour and less than 10% of the released Nipah virus RNA was infectious. Conclusion The SYBR® Green I-based qRT-PCR assay enabled quantitative assessment of Nipah virus RNA synthesis in Vero cells. A low rate of Nipah virus extracellular RNA release and low infectious virus yield together with extensive syncytial formation during the infection support a cell-to-cell spread mechanism for Nipah virus infection.

  4. Polyomavirus specific cellular immunity: from BK-virus-specific cellular immunity to BK-virus-associated nephropathy ?

    Directory of Open Access Journals (Sweden)

    manon edekeyser

    2015-06-01

    Full Text Available In renal transplantation, BK-virus-associated nephropathy has emerged as a major complication, with a prevalence of 5–10% and graft loss in >50% of cases. BK-virus is a member of the Polyomavirus family and rarely induces apparent clinical disease in the general population. However, replication of polyomaviruses, associated with significant organ disease, is observed in patients with acquired immunosuppression, which suggests a critical role for virus-specific cellular immunity to control virus replication and prevent chronic disease. Monitoring of specific immunity combined with viral load could be used to individually assess the risk of viral reactivation and virus control. We review the current knowledge on BK-virus specific cellular immunity and, more specifically, in immunocompromised patients. In the future, immune-based therapies could allow us to treat and prevent BK-virus-associated nephropathy.

  5. The complete nucleotide sequence and genomic characterization of grapevine asteroid mosaic associated virus.

    Science.gov (United States)

    Vargas-Asencio, José; Wojciechowska, Klaudia; Baskerville, Maia; Gomez, Annika L; Perry, Keith L; Thompson, Jeremy R

    2017-01-02

    In analyzing grapevine clones infected with grapevine red blotch associated virus, we identified a small number of isometric particles of approximately 30nm in diameter from an enriched fraction of leaf extract. A dominant protein of 25kDa was isolated from this fraction using SDS-PAGE and was identified by mass spectrometry as belonging to grapevine asteroid mosaic associated virus (GAMaV). Using a combination of three methods RNA-Seq, sRNA-Seq, and Sanger sequencing of RT- and RACE-PCR products, we obtained a full-length genome sequence consisting of 6719 nucleotides without the poly(A) tail. The virus possesses all of the typical conserved functional domains concordant with the genus Marafivirus and lies evolutionarily between citrus sudden death associated virus and oat blue dwarf virus. A large shift in RNA-Seq coverage coincided with the predicted location of the subgenomic RNA involved in coat protein (CP) expression. Genus wide sequence alignments confirmed the cleavage motif LxG(G/A) to be dominant between the helicase and RNA dependent RNA polymerase (RdRp), and the RdRp and CP domains. A putative overlapping protein (OP) ORF lacking a canonical translational start codon was identified with a reading frame context more consistent with the putative OPs of tymoviruses and fig fleck associated virus than with those of marafiviruses. BLAST analysis of the predicted GAMaV OP showed a unique relatedness to the OPs of members of the genus Tymovirus. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Biological and historical overview of Zika virus

    Science.gov (United States)

    Armstrong, Najealicka; Hou, Wangheng; Tang, Qiyi

    2017-01-01

    The recent outbreak of the Zika virus attracts worldwide attention probably because the most recently affected country (Brazil) will host the 2016 Olympic Game. Zika virus infected cases are now spreading to many other countries and its infection might be linked to some severe medical sequelae. Since its first isolation from the infected monkey in 1947 in Uganda, only a few studies had been taken until recent outbreak. According to the history of referenced publications, there is a 19-year gap from 1989 to 2007. This might be because only mild diseases were diagnosed from Zika virus infected populations. Obviously, the recent reports that Zika virus infection is probably associated with microcephaly of the neonates makes us reevaluate the medical significance of the viral pathogen. It can be transmitted sexually or by mosquito biting. Sexual transmission of the Zika virus distinguishes it from other members of the Genus Flavivirus. Detailed information of the Zika virus is needed through a thorough investigation covering basic, epidemical, subclinical and clinical studies. Here, we reviewed the published information of Zika virus. PMID:28239566

  7. Viral microRNAs targeting virus genes promote virus infection in shrimp in vivo.

    Science.gov (United States)

    He, Yaodong; Yang, Kai; Zhang, Xiaobo

    2014-01-01

    Viral microRNAs (miRNAs), most of which are characterized in cell lines, have been found to play important roles in the virus life cycle to avoid attack by the host immune system or to keep virus in the latency state. Viral miRNAs targeting virus genes can inhibit virus infection. In this study, in vivo findings in Marsupenaeus japonicus shrimp revealed that the viral miRNAs could target virus genes and further promote the virus infection. The results showed that white spot syndrome virus (WSSV)-encoded miRNAs WSSV-miR-66 and WSSV-miR-68 were transcribed at the early stage of WSSV infection. When the expression of WSSV-miR-66 and WSSV-miR-68 was silenced with sequence-specific anti-miRNA oligonucleotides (AMOs), the number of copies of WSSV and the WSSV-infected shrimp mortality were significantly decreased, indicating that the two viral miRNAs had a great effect on virus infection. It was revealed that the WSSV wsv094 and wsv177 genes were the targets of WSSV-miR-66 and that the wsv248 and wsv309 genes were the targets of WSSV-miR-68. The data demonstrate that the four target genes play negative roles in the WSSV infection. The targeting of the four virus genes by WSSV-miR-66 and WSSV-miR-68 led to the promotion of virus infection. Therefore, our in vivo findings show a novel aspect of viral miRNAs in virus-host interactions.

  8. Viruses in cancer cell plasticity: the role of hepatitis C virus in hepatocellular carcinoma.

    Science.gov (United States)

    Hibner, Urszula; Grégoire, Damien

    2015-01-01

    Viruses are considered as causative agents of a significant proportion of human cancers. While the very stringent criteria used for their classification probably lead to an underestimation, only six human viruses are currently classified as oncogenic. In this review we give a brief historical account of the discovery of oncogenic viruses and then analyse the mechanisms underlying the infectious causes of cancer. We discuss viral strategies that evolved to ensure virus propagation and spread can alter cellular homeostasis in a way that increases the probability of oncogenic transformation and acquisition of stem cell phenotype. We argue that a useful way of analysing the convergent characteristics of viral infection and cancer is to examine how viruses affect the so-called cancer hallmarks. This view of infectious origin of cancer is illustrated by examples from hepatitis C infection, which is associated with a high proportion of hepatocellular carcinoma.

  9. PRESENCE OF RESPIRATORY VIRUSES IN EQUINES IN BRAZIL

    Directory of Open Access Journals (Sweden)

    Dalva Assunção Portari Mancini

    2014-06-01

    Full Text Available Equines are susceptible to respiratory viruses such as influenza and parainfluenza. Respiratory diseases have adversely impacted economies all over the world. This study was intended to determine the presence of influenza and parainfluenza viruses in unvaccinated horses from some regions of the state of São Paulo, Brazil. Blood serum collected from 72 equines of different towns in this state was tested by hemagglutination inhibition test to detect antibodies for both viruses using the corresponding antigens. About 98.6% (71 and 97.2% (70 of the equines responded with antibody protective titers (≥ 80 HIU/25µL H7N7 and H3N8 subtypes of influenza A viruses, respectively. All horses (72 also responded with protective titers (≥ 80 HIU/25µL against the parainfluenza virus. The difference between mean antibody titers to H7N7 and H3N8 subtypes of influenza A viruses was not statistically significant (p > 0.05. The mean titers for influenza and parainfluenza viruses, on the other hand, showed a statistically significant difference (p < 0.001. These results indicate a better antibody response from equines to parainfluenza 3 virus than to the equine influenza viruses. No statistically significant differences in the responses against H7N7 and H3N8 subtypes of influenza A and parainfluenza 3 viruses were observed according to the gender (female, male or the age (≤ 2 to 20 years-old groups. This study provides evidence of the concomitant presence of two subtypes of the equine influenza A (H7N7 and H3N8 viruses and the parainfluenza 3 virus in equines in Brazil. Thus, it is advisable to vaccinate equines against these respiratory viruses.

  10. Postmortem stability of Ebola virus.

    Science.gov (United States)

    Prescott, Joseph; Bushmaker, Trenton; Fischer, Robert; Miazgowicz, Kerri; Judson, Seth; Munster, Vincent J

    2015-05-01

    The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus-infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated <7 days posteuthanasia; viral RNA was detectable for 10 weeks.

  11. Inhibitors of the interferon response enhance virus replication in vitro.

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    Claire E Stewart

    Full Text Available Virus replication efficiency is influenced by two conflicting factors, kinetics of the cellular interferon (IFN response and induction of an antiviral state versus speed of virus replication and virus-induced inhibition of the IFN response. Disablement of a virus's capacity to circumvent the IFN response enables both basic research and various practical applications. However, such IFN-sensitive viruses can be difficult to grow to high-titer in cells that produce and respond to IFN. The current default option for growing IFN-sensitive viruses is restricted to a limited selection of cell-lines (e.g. Vero cells that have lost their ability to produce IFN. This study demonstrates that supplementing tissue-culture medium with an IFN inhibitor provides a simple, effective and flexible approach to increase the growth of IFN-sensitive viruses in a cell-line of choice. We report that IFN inhibitors targeting components of the IFN response (TBK1, IKK2, JAK1 significantly increased virus replication. More specifically, the JAK1/2 inhibitor Ruxolitinib enhances the growth of viruses that are sensitive to IFN due to (i loss of function of the viral IFN antagonist (due to mutation or species-specific constraints or (ii mutations/host cell constraints that slow virus spread such that it can be controlled by the IFN response. This was demonstrated for a variety of viruses, including, viruses with disabled IFN antagonists that represent live-attenuated vaccine candidates (Respiratory Syncytial Virus (RSV, Influenza Virus, traditionally attenuated vaccine strains (Measles, Mumps and a slow-growing wild-type virus (RSV. In conclusion, supplementing tissue culture-medium with an IFN inhibitor to increase the growth of IFN-sensitive viruses in a cell-line of choice represents an approach, which is broadly applicable to research investigating the importance of the IFN response in controlling virus infections and has utility in a number of practical applications

  12. Virus-Vectored Influenza Virus Vaccines

    OpenAIRE

    Tripp, Ralph A.; Tompkins, S. Mark

    2014-01-01

    Despite the availability of an inactivated vaccine that has been licensed for >50 years, the influenza virus continues to cause morbidity and mortality worldwide. Constant evolution of circulating influenza virus strains and the emergence of new strains diminishes the effectiveness of annual vaccines that rely on a match with circulating influenza strains. Thus, there is a continued need for new, efficacious vaccines conferring cross-clade protection to avoid the need for biannual reformul...

  13. Presence and Distribution of Oilseed Pumpkin Viruses and Molecular Detection of Zucchini Yellow Mosaic Virus

    Directory of Open Access Journals (Sweden)

    Ana Vučurović

    2009-01-01

    Full Text Available Over the past decade, intensive spread of virus infections of oilseed pumpkin has resulted in significant economic losses in pumpkin crop production, which is currently expanding in our country. In 2007 and 2008, a survey for the presence and distribution of oilseed pumpkin viruses was carried out in order to identify viruses responsible for epidemics and incidences of very destructive symptoms on cucurbit leaves and fruits. Monitoring andcollecting samples of oil pumpkin, as well as other species such as winter and butternut squash and buffalo and bottle gourd with viral infection symptoms, was conducted in several localities of Vojvodina Province. The collected plant samples were tested by DAS-ELISA using polyclonal antisera specific for the detection of six most economically harmful pumpkin viruses: Cucumber mosaic virus (CMV, Zucchini yellow mosaic virus (ZYMV, Watermelon mosaic virus (WMW, Squash mosaic virus (SqMV, Papaya ringspot virus (PRSV and Tobaccoringspot virus (TRSV that are included in A1 quarantine list of harmful organisms in Serbia.Identification of viruses in the collected samples indicated the presence of three viruses, ZYMV, WMV and CMV, in individual and mixed infections. Frequency of the identified viruses varied depending on locality and year of investigations. In 2007, WMV was the most frequent virus (94.2%, while ZYMV was prevalent (98.04% in 2008. High frequency of ZYMV determined in both years of investigation indicated the need for its rapid and reliable molecular detection. During this investigation, a protocol for ZYMVdetection was developed and optimized using specific primers CPfwd/Cprev and commercial kits for total RNA extraction, as well as for RT-PCR. In RT-PCR reaction using these primers, a DNA fragment of approximately 1100 bp, which included coat protein gene, was amplified in the samples of infected pumkin leaves. Although serological methods are still useful for large-scale testing of a great number of

  14. Vector-Virus Interactions and Transmission Dynamics of West Nile Virus

    Science.gov (United States)

    Ciota, Alexander T.; Kramer, Laura D.

    2013-01-01

    West Nile virus (WNV; Flavivirus; Flaviviridae) is the cause of the most widespread arthropod-borne viral disease in the world and the largest outbreak of neuroinvasive disease ever observed. Mosquito-borne outbreaks are influenced by intrinsic (e.g., vector and viral genetics, vector and host competence, vector life-history traits) and extrinsic (e.g., temperature, rainfall, human land use) factors that affect virus activity and mosquito biology in complex ways. The concept of vectorial capacity integrates these factors to address interactions of the virus with the arthropod host, leading to a clearer understanding of their complex interrelationships, how they affect transmission of vector-borne disease, and how they impact human health. Vertebrate factors including host competence, population dynamics, and immune status also affect transmission dynamics. The complexity of these interactions are further exacerbated by the fact that not only can divergent hosts differentially alter the virus, but the virus also can affect both vertebrate and invertebrate hosts in ways that significantly alter patterns of virus transmission. This chapter concentrates on selected components of the virus-vector-vertebrate interrelationship, focusing specifically on how interactions between vector, virus, and environment shape the patterns and intensity of WNV transmission. PMID:24351794

  15. Methamphetamine reduces human influenza A virus replication.

    Directory of Open Access Journals (Sweden)

    Yun-Hsiang Chen

    Full Text Available Methamphetamine (meth is a highly addictive psychostimulant that is among the most widely abused illicit drugs, with an estimated over 35 million users in the world. Several lines of evidence suggest that chronic meth abuse is a major factor for increased risk of infections with human immunodeficiency virus and possibly other pathogens, due to its immunosuppressive property. Influenza A virus infections frequently cause epidemics and pandemics of respiratory diseases among human populations. However, little is known about whether meth has the ability to enhance influenza A virus replication, thus increasing severity of influenza illness in meth abusers. Herein, we investigated the effects of meth on influenza A virus replication in human lung epithelial A549 cells. The cells were exposed to meth and infected with human influenza A/WSN/33 (H1N1 virus. The viral progenies were titrated by plaque assays, and the expression of viral proteins and cellular proteins involved in interferon responses was examined by Western blotting and immunofluorescence staining. We report the first evidence that meth significantly reduces, rather than increases, virus propagation and the susceptibility to influenza infection in the human lung epithelial cell line, consistent with a decrease in viral protein synthesis. These effects were apparently not caused by meth's effects on enhancing virus-induced interferon responses in the host cells, reducing viral biological activities, or reducing cell viability. Our results suggest that meth might not be a great risk factor for influenza A virus infection among meth abusers. Although the underlying mechanism responsible for the action of meth on attenuating virus replication requires further investigation, these findings prompt the study to examine whether other structurally similar compounds could be used as anti-influenza agents.

  16. Purple coneflower viruses: species diversity and harmfulness

    Directory of Open Access Journals (Sweden)

    Dunich A. A.

    2015-02-01

    Full Text Available Viral diseases became an actual problem in medicinal plants cultivation. The number of viruses known to infect purple coneflower increased significantly in the last years in many countries. However, there is no any review about the viral diseases of this valuable medicinal crop. Therefore, the aim of this article is to summarize the main information about the viruses affecting purple coneflower plants (Echinacea purpurea L. Moench.. An analysis of the literature data showed that purple coneflower could be infected by 10 viruses. These viruses belong to the families Bromoviridae, Bunyaviridae, Secoviridae, Potyviridae, Vir­ga­vi­ri­dae, and almost all of them are considered to be highly harmful plant viruses. Additionally, four of them (TMV, TSWV, CMV, PVY are in the top 10 of the most economically important plant viruses in the world and occupy the first places. Such distribution and harmfulness of these viruses are explained by a wide range of sensitive host-plants, wild plants and weeds – reservoirs of an infection, and also a large number of vectors. The data from a few countries show that the viral diseases of purple coneflower are becoming more severe from year to year. The appearance of new viruses is registered on coneflower every year that complicates prognosis and risk estimation of epiphytoties in these regions which, for example, were revealed in Bulgaria, Lithuania and Ukraine. This review presents the detailed symptoms of the viral diseases in purple coneflower, the main properties of each virus and data about their harmful effect on the quality of raw material (the concentration of biologically active substances and heavy metals in plants.

  17. DNA Virus Replication Compartments

    Science.gov (United States)

    Schmid, Melanie; Speiseder, Thomas; Dobner, Thomas

    2014-01-01

    Viruses employ a variety of strategies to usurp and control cellular activities through the orchestrated recruitment of macromolecules to specific cytoplasmic or nuclear compartments. Formation of such specialized virus-induced cellular microenvironments, which have been termed viroplasms, virus factories, or virus replication centers, complexes, or compartments, depends on molecular interactions between viral and cellular factors that participate in viral genome expression and replication and are in some cases associated with sites of virion assembly. These virus-induced compartments function not only to recruit and concentrate factors required for essential steps of the viral replication cycle but also to control the cellular mechanisms of antiviral defense. In this review, we summarize characteristic features of viral replication compartments from different virus families and discuss similarities in the viral and cellular activities that are associated with their assembly and the functions they facilitate for viral replication. PMID:24257611

  18. Viruses of the Archaea

    DEFF Research Database (Denmark)

    Basta, T.; Garrett, Roger Antony; Prangishvili,, David

    2009-01-01

    Double-stranded deoxyribonucleic acid (DNA) viruses that infect members of the third domain of life, the Archaea, are diverse and exceptional in both their morphotypes and their genomic properties. The majority of characterized species infect hyperthermophilic hosts and carry morphological features...... which have not been observed for viruses from the other domains of life, the Bacteria and the Eukarya. This exceptional status of the archaeal viruses is reinforced by the finding that a large majority of their predicted genes yield no sequence matches in public sequence databases, and their functions...... remain unknown. One of the viruses, the bicaudavirus ATV (Acidianus two-tailed virus), is quite unique in that it undergoes a major morphological change, growing long tail structures, extracellularly. A small minority of archaeal viruses, which exclusively infect mesophilic or moderately thermophilic...

  19. Constructing computer virus phylogenies

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, L.A. [Warwick Univ., Coventry (United Kingdom) Dept. of Computer Science; Goldberg, P.W. [Aston Univ., Birmingham (United Kingdom) Dept. of Applied Mathematics; Phillips, C.A. [Sandia National Labs., Albuquerque, NM (United States); Sorkin, G.B. [International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center

    1996-03-01

    There has been much recent algorithmic work on the problem of reconstructing the evolutionary history of biological species. Computer virus specialists are interested in finding the evolutionary history of computer viruses--a virus is often written using code fragments from one or more other viruses, which are its immediate ancestors. A phylogeny for a collection of computer viruses is a directed acyclic graph whose nodes are the viruses and whose edges map ancestors to descendants and satisfy the property that each code fragment is ``invented`` only once. To provide a simple explanation for the data, we consider the problem of constructing such a phylogeny with a minimal number of edges. In general, this optimization problem cannot be solved in quasi-polynomial time unless NQP=QP; we present positive and negative results for associated approximated problems. When tree solutions exist, they can be constructed and randomly sampled in polynomial time.

  20. Asymptomatic reactivation of JC virus in patients treated with natalizumab.

    Science.gov (United States)

    Chen, Yiping; Bord, Evelyn; Tompkins, Troy; Miller, Janice; Tan, Chen S; Kinkel, R Philip; Stein, Marion C; Viscidi, Raphael P; Ngo, Long H; Koralnik, Igor J

    2009-09-10

    Progressive multifocal leukoencephalopathy (PML) occurs in a fraction of patients with multiple sclerosis who were treated with natalizumab. Most adults who are infected with the JC virus, the etiologic agent in PML, do not have symptoms. We sought to determine whether exposure to natalizumab causes subclinical reactivation and neurotropic transformation of JC virus. We followed 19 consecutive patients with multiple sclerosis who were treated with natalizumab over an 18-month period, performing quantitative polymerase-chain-reaction assays in blood and urine for JC virus reactivation; BK virus, a JC virus-related polyomavirus, was used as a control. We determined JC virus-specific T-cell responses by means of an enzyme-linked immunospot assay and antibody responses by means of an enzyme-linked immunosorbent assay and analyzed JC virus regulatory-region sequences. After 12 months of natalizumab therapy, the prevalence of JC virus in the urine of the 19 patients increased from a baseline value of 19% to 63% (P=0.02). After 18 months of treatment, JC virus was detectable in 3 of 15 available plasma samples (20%) and in 9 of 15 available samples of peripheral-blood mononuclear cells (60%) (P=0.02). JC virus regulatory-region sequences in blood samples and in most of the urine samples were similar to those usually found in PML. Conversely, BK virus remained stable in urine and was undetectable in blood. The JC virus-specific cellular immune response dropped significantly between 6 and 12 months of treatment, and variations in the cellular immune response over time tended to be greater in patients in whom JC viremia developed. None of the patients had clinical or radiologic signs of PML. Subclinical reactivation of JC virus occurs frequently in natalizumab-treated patients with multiple sclerosis. Viral shedding is associated with a transient drop in the JC virus-specific cellular immune response. 2009 Massachusetts Medical Society

  1. Data mining and analysis of bacillus virus

    Directory of Open Access Journals (Sweden)

    An Jiwoo

    2016-01-01

    Full Text Available Anthrax- can be found naturally in soil and commonly affects domestic and wild animals around the world. Bacillus anthracis is mostly common viruses of Anthrax. There are some more occurred in similar DNA sequences: 3 Bacillus Viruses: Bacillus anthracis, Bacillus cereus, and Bacillus thuringiensis. This is a report about analyzing the similarities between the Bacillus viruses by investigating the frequency of amino acid and finding the difference between those three viruses based on the gene. Those diseases are infected by parasite and host animals, and cause muscle pain. Therefore, we can conclude that Leucine is a protein that plays a significant role in causing muscle pain. Secondly, In Analysis of decision tree, there are only little differences between each classes. The classes represent positions that include representative protein. The very position that windows mention is their difference.

  2. Zika virus infection.

    Science.gov (United States)

    Pougnet, Laurence; Thill, Chloé; Pougnet, Richard; Auvinet, Henri; Giacardi, Christophe; Drouillard, Isabelle

    2016-12-01

    A 21-year old woman from New-Caledonia had 40 ̊C fever with vomiting, arthralgia, myalgia, and measles-like rash. Etiological analyses showed primary infection with Zika virus. Because of severe clinical presentation, she was hospitalized in the intensive care unit of the Brest military Hospital. Zika virus is mainly transmitted by Aedes mosquitoes. If they settle in Metropolitan France, Zika virus might also spread there.

  3. Personal computer viruses

    Energy Technology Data Exchange (ETDEWEB)

    Cremonesi, C.; Martella, G. (Milan Univ. (Italy). Dipt. di Scienza dell' Informazione)

    1991-01-01

    This article reveals the origin and nature of what is known as the 'computer virus'. For illustrative purposes, the most common types of computer viruses are described and classified; the relative contagion and damage mechanisms are analyzed. Then techniques are presented to assist wary users in detecting and removing viruses, as well as, in protecting their computer systems from becoming contaminated.

  4. Electron microscopy of viruses.

    Science.gov (United States)

    Laue, Michael

    2010-01-01

    Electron microscopy is widely used in virology because viruses are generally too small for a direct inspection by light microscopy. Analysis of virus morphology is necessary in many circumstances, e.g., for the diagnosis of a virus in particular clinical situations or the analysis of virus entry and assembly. Moreover, quality control of virus particle integrity is required if a virus is propagated in cell culture, particularly if the virus genome has changed. In most cases already the basic methodology for transmission electron microscopy, i.e., negative staining and ultrathin sectioning, is sufficient to give relevant information on virus ultrastructure. This chapter gives detailed information on the principles of these basic methodologies and provides simple but reliable protocols for a quick start. Moreover, the description of standard protocols for negative staining and ultrathin sectioning are supplemented by protocols on immuno-negative staining and rapid ultrathin sectioning. Finally, principles of methods for an extended ultrastructural research using more elaborate techniques, such as cryotechniques or methods to reveal the three-dimensional virus architecture, are briefly reviewed. Copyright © 2010 Elsevier Inc. All rights reserved.

  5. Viruses infecting marine molluscs.

    Science.gov (United States)

    Arzul, Isabelle; Corbeil, Serge; Morga, Benjamin; Renault, Tristan

    2017-07-01

    Although a wide range of viruses have been reported in marine molluscs, most of these reports rely on ultrastructural examination and few of these viruses have been fully characterized. The lack of marine mollusc cell lines restricts virus isolation capacities and subsequent characterization works. Our current knowledge is mostly restricted to viruses affecting farmed species such as oysters Crassostrea gigas, abalone Haliotis diversicolor supertexta or the scallop Chlamys farreri. Molecular approaches which are needed to identify virus affiliation have been carried out for a small number of viruses, most of them belonging to the Herpesviridae and birnaviridae families. These last years, the use of New Generation Sequencing approach has allowed increasing the number of sequenced viral genomes and has improved our capacity to investigate the diversity of viruses infecting marine molluscs. This new information has in turn allowed designing more efficient diagnostic tools. Moreover, the development of experimental infection protocols has answered some questions regarding the pathogenesis of these viruses and their interactions with their hosts. Control and management of viral diseases in molluscs mostly involve active surveillance, implementation of effective bio security measures and development of breeding programs. However factors triggering pathogen development and the life cycle and status of the viruses outside their mollusc hosts still need further investigations. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Yeast for virus research

    Science.gov (United States)

    Zhao, Richard Yuqi

    2017-01-01

    Budding yeast (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe) are two popular model organisms for virus research. They are natural hosts for viruses as they carry their own indigenous viruses. Both yeasts have been used for studies of plant, animal and human viruses. Many positive sense (+) RNA viruses and some DNA viruses replicate with various levels in yeasts, thus allowing study of those viral activities during viral life cycle. Yeasts are single cell eukaryotic organisms. Hence, many of the fundamental cellular functions such as cell cycle regulation or programed cell death are highly conserved from yeasts to higher eukaryotes. Therefore, they are particularly suited to study the impact of those viral activities on related cellular activities during virus-host interactions. Yeasts present many unique advantages in virus research over high eukaryotes. Yeast cells are easy to maintain in the laboratory with relative short doubling time. They are non-biohazardous, genetically amendable with small genomes that permit genome-wide analysis of virologic and cellular functions. In this review, similarities and differences of these two yeasts are described. Studies of virologic activities such as viral translation, viral replication and genome-wide study of virus-cell interactions in yeasts are highlighted. Impacts of viral proteins on basic cellular functions such as cell cycle regulation and programed cell death are discussed. Potential applications of using yeasts as hosts to carry out functional analysis of small viral genome and to develop high throughput drug screening platform for the discovery of antiviral drugs are presented. PMID:29082230

  7. Polyomavirus-Specific Cellular Immunity: From BK-Virus-Specific Cellular Immunity to BK-Virus-Associated Nephropathy?

    OpenAIRE

    manon edekeyser; helene efrancois; severine ebeaudreuil; Antoine eDurrbach

    2015-01-01

    In renal transplantation, BK-virus-associated nephropathy has emerged as a major complication, with a prevalence of 5–10% and graft loss in >50% of cases. BK-virus is a member of the Polyomavirus family and rarely induces apparent clinical disease in the general population. However, replication of polyomaviruses, associated with significant organ disease, is observed in patients with acquired immunosuppression, which suggests a critical role for virus-specific cellular immunity to control vir...

  8. Guillain-Barre syndrome presenting with sensory disturbance following a herpes virus infection: a case report

    Directory of Open Access Journals (Sweden)

    Ntziora Fotinie

    2011-12-01

    negative for cytomegalovirus immunoglobulin M, Epstein-Barr virus immunoglobulin M and varicella zoster virus immunoglobulin M. Conclusions The clinical manifestation of Guillain-Barre syndrome in our patient followed a combined herpes virus infection. The cross-reactivity between these human herpes viruses may have a pathogenic as well as evolutionary significance. Our patient showed seroconversion at an early stage of Epstein-Barr virus immunoglobulin M to immunoglobulin G antibodies, suggesting that Epstein-Barr virus might have been the cause of this syndrome. Even if this case is not the first of its kind to be reported, it may contribute to a better understanding of the disease and the cross-reaction mechanisms of herpes virus infections. This case report may have a broader clinical impact across more than one area of medicine, suggesting that cooperation between different specialties is always in the patient's best interest.

  9. Viruses in pulp and periapical inflammation: a review.

    Science.gov (United States)

    Hernández Vigueras, Scarlette; Donoso Zúñiga, Manuel; Jané-Salas, Enric; Salazar Navarrete, Luis; Segura-Egea, Juan José; Velasco-Ortega, Eugenio; López-López, José

    2016-05-01

    The presence of viruses in endodontic disease has been studied in the last decade. Their presence is associated with periapical radiolucency and with clinical findings, such as pain. The aim of this review is to analyze the scientific evidence currently published about viruses in pulp and periapical inflammation, and its possible clinical implications. A literature review was carried out using the Medline/Pubmed database. The search was performed, in English and Spanish, using the following keyword combinations: virus AND endodontic; virus AND periapical; virus AND pulpitis; herpesvirus AND periapical; papillomavirus AND periapical. We subsequently selected the most relevant studies, which complied with the search criterion. A total of 21 articles were included, of which 18 detected the present of viruses in the samples. In 3 of the studies, viral presence was not found in the samples studied. The Epstein-Barr virus was found in about 41 % of cases compared to controls, in which it was present in about 2 %. The main association between viruses and endodontic pathosis is between Cytomegalovirus and Epstein-Barr virus; these are found in 114 of the 406 samples of different endodontic pathosis. Some evidence supports that the Epstein-Barr virus is present in a significant number of endodontic diseases, without exact knowledge of their action in these diseases.

  10. Viral Aggregation: Impact on Virus Behavior in the Environment.

    Science.gov (United States)

    Gerba, Charles P; Betancourt, Walter Q

    2017-07-05

    Aggregates of viruses can have a significant impact on quantification and behavior of viruses in the environment. Viral aggregates may be formed in numerous ways. Viruses may form crystal like structures and aggregates in the host cell during replication or may form due to changes in environmental conditions after virus particles are released from the host cells. Aggregates tend to form near the isoelectric point of the virus, under the influence of certain salts and salt concentrations in solution, cationic polymers, and suspended organic matter. The given conditions under which aggregates form in the environment are highly dependent on the type of virus, type of salts in solution (cation, anion. monovalent, divalent) and pH. However, virus type greatly influences the conditions when aggregation/disaggregation will occur, making predictions difficult under any given set of water quality conditions. Most studies have shown that viral aggregates increase the survival of viruses in the environment and resistance to disinfectants, especially with more reactive disinfectants. The presence of viral aggregates may also result in overestimation of removal by filtration processes. Virus aggregation-disaggregation is a complex process and predicting the behavior of any individual virus is difficult under a given set of environmental circumstances without actual experimental data.

  11. Significant scales in community structure.

    Science.gov (United States)

    Traag, V A; Krings, G; Van Dooren, P

    2013-10-14

    Many complex networks show signs of modular structure, uncovered by community detection. Although many methods succeed in revealing various partitions, it remains difficult to detect at what scale some partition is significant. This problem shows foremost in multi-resolution methods. We here introduce an efficient method for scanning for resolutions in one such method. Additionally, we introduce the notion of "significance" of a partition, based on subgraph probabilities. Significance is independent of the exact method used, so could also be applied in other methods, and can be interpreted as the gain in encoding a graph by making use of a partition. Using significance, we can determine "good" resolution parameters, which we demonstrate on benchmark networks. Moreover, optimizing significance itself also shows excellent performance. We demonstrate our method on voting data from the European Parliament. Our analysis suggests the European Parliament has become increasingly ideologically divided and that nationality plays no role.

  12. Deliberate attenuation of chikungunya virus by adaptation to heparan sulfate-dependent infectivity: a model for rational arboviral vaccine design.

    Directory of Open Access Journals (Sweden)

    Christina L Gardner

    2014-02-01

    Full Text Available Mosquito-borne chikungunya virus (CHIKV is a positive-sense, single-stranded RNA virus from the genus Alphavirus, family Togaviridae, which causes fever, rash and severe persistent polyarthralgia in humans. Since there are currently no FDA licensed vaccines or antiviral therapies for CHIKV, the development of vaccine candidates is of critical importance. Historically, live-attenuated vaccines (LAVs for protection against arthropod-borne viruses have been created by blind cell culture passage leading to attenuation of disease, while maintaining immunogenicity. Attenuation may occur via multiple mechanisms. However, all examined arbovirus LAVs have in common the acquisition of positively charged amino acid substitutions in cell-surface attachment proteins that render virus infection partially dependent upon heparan sulfate (HS, a ubiquitously expressed sulfated polysaccharide, and appear to attenuate by retarding dissemination of virus particles in vivo. We previously reported that, like other wild-type Old World alphaviruses, CHIKV strain, La Réunion, (CHIKV-LR, does not depend upon HS for infectivity. To deliberately identify CHIKV attachment protein mutations that could be combined with other attenuating processes in a LAV candidate, we passaged CHIKV-LR on evolutionarily divergent cell-types. A panel of single amino acid substitutions was identified in the E2 glycoprotein of passaged virus populations that were predicted to increase electrostatic potential. Each of these substitutions was made in the CHIKV-LR cDNA clone and comparisons of the mutant viruses revealed surface exposure of the mutated residue on the spike and sensitivity to competition with the HS analog, heparin, to be primary correlates of attenuation in vivo. Furthermore, we have identified a mutation at E2 position 79 as a promising candidate for inclusion in a CHIKV LAV.

  13. Sequence and Structure Analysis of Distantly-Related Viruses Reveals Extensive Gene Transfer between Viruses and Hosts and among Viruses

    Science.gov (United States)

    Caprari, Silvia; Metzler, Saskia; Lengauer, Thomas; Kalinina, Olga V.

    2015-01-01

    The origin and evolution of viruses is a subject of ongoing debate. In this study, we provide a full account of the evolutionary relationships between proteins of significant sequence and structural similarity found in viruses that belong to different classes according to the Baltimore classification. We show that such proteins can be found in viruses from all Baltimore classes. For protein families that include these proteins, we observe two patterns of the taxonomic spread. In the first pattern, they can be found in a large number of viruses from all implicated Baltimore classes. In the other pattern, the instances of the corresponding protein in species from each Baltimore class are restricted to a few compact clades. Proteins with the first pattern of distribution are products of so-called viral hallmark genes reported previously. Additionally, this pattern is displayed by the envelope glycoproteins from Flaviviridae and Bunyaviridae and helicases of superfamilies 1 and 2 that have homologs in cellular organisms. The second pattern can often be explained by horizontal gene transfer from the host or between viruses, an example being Orthomyxoviridae and Coronaviridae hemagglutinin esterases. Another facet of horizontal gene transfer comprises multiple independent introduction events of genes from cellular organisms into otherwise unrelated viruses. PMID:26492264

  14. Determination of Cultural Conditions of Infectious Bovine Rhinotracheitis Virus Strain “BM”

    Directory of Open Access Journals (Sweden)

    Myroslava Hulyanych

    2016-09-01

    Full Text Available The purpose of our research was to determine cultural properties and cultural conditions of the infectious bovine rhinotracheitis virus of “BM” strain. Sensitivity of different cell lines to IBR virus was studied. The most effective system for cultivation of IBR virus turned MDBK cell line. Optimum multiplicity of infection was 0.01 TCD50/cell in which infectious virus replication activity is the highest. The research work proved that influence of maintenance medium and the presence of serum had no effect on the virus productivity. It was also proved that the method of infection significantly effects on intensity of accumulation of the virus.

  15. Global analysis of population structure, spatial and temporal dynamics of genetic diversity, and evolutionary lineages of Iris yellow spot virus (Tospovirus: Bunyaviridae).

    Science.gov (United States)

    Iftikhar, Romana; Ramesh, Shunmugiah V; Bag, Sudeep; Ashfaq, Muhammad; Pappu, Hanu R

    2014-08-15

    Thrips-transmitted Iris yellow spot virus is an economically important viral pathogen of Allium crops worldwide. A global analysis of known IYSV nucleocapsid gene (N gene) sequences was carried out to determine the comparative population structure, spatial and temporal dynamics with reference to its genetic diversity and evolution. A total of 98 complete N gene sequences (including 8 sequences reported in this study) available in GenBank and reported from 23 countries were characterized by in-silico RFLP analysis. Based on RFLP, 94% of the isolates could be grouped into NL or BR types while the rest belonged to neither group. The relative proportion of NL and BR types was 46% and 48%, respectively. A temporal shift in the IYSV genotypes with a greater incremental incidence of IYSVBR was found over IYSVNL before 2005 compared to after 2005. The virus population had at least one evolutionarily significant recombination event, involving IYSVBR and IYSVNL. Codon substitution studies did not identify any significant differences among the genotypes of IYSV. However, N gene codons were minimally positively selected, moderately negatively selected denoting the action of purifying selection, thus rejecting the theory of neutral mutation in IYSV population. However, one codon position (139) was found to be positively selected in all the genotypes. Population selection statistics in the IYSVBR, IYSVNL genotypes and in the population as a whole also revealed the action of purifying selection or population expansion, whereas IYSVother displayed a decrease in population size. Genetic differentiation studies showed inherent differentiation and infrequent gene flow between IYSVBR and IYSVNL genotypes corroborating the geographical confinement of these genotypes. Taken together the study suggests that the observed diversity in IYSV population and temporal shift in IYSVBR genotype is attributable to genetic recombination, abundance of purifying selection, insignificant positive

  16. Exceptionally diverse morphotypes and genomes of crenarchaeal hyperthermophilic viruses

    DEFF Research Database (Denmark)

    Prangishvili, D; Garrett, R A

    2004-01-01

    The remarkable diversity of the morphologies of viruses found in terrestrial hydrothermal environments with temperatures >80 degrees C is unprecedented for aquatic ecosystems. The best-studied viruses from these habitats have been assigned to novel viral families: Fuselloviridae, Lipothrixviridae...... no significant matches to sequences in public databases. This suggests that these hyperthermophilic viruses have exceptional biochemical solutions for biological functions. Specific features of genome organization, as well as strategies for DNA replication, suggest that phylogenetic relationships exist between...... crenarchaeal rudiviruses and the large eukaryal DNA viruses: poxviruses, the African swine fever virus and Chlorella viruses. Sequence patterns at the ends of the linear genome of the lipothrixvirus AFV1 are reminiscent of the telomeric ends of linear eukaryal chromosomes and suggest that a primitive telomeric...

  17. A compartmental model for computer virus propagation with kill signals

    Science.gov (United States)

    Ren, Jianguo; Xu, Yonghong

    2017-11-01

    Research in the area of kill signals for prevention of computer virus is of significant importance for computer users. The kill signals allow computer users to take precautions beforehand. In this paper, a computer virus propagation model based on the kill signals, called SEIR-KS model, is formulated and full dynamics of the proposed model are theoretically analyzed. An epidemic threshold is obtained and the existence and uniqueness of the virus equilibrium are investigated. It is proved that the virus-free equilibrium and virus equilibrium are locally and globally asymptotically stable by applying Routh-Hurwitz criterion and Lyapunov functional approach. The results of numerical simulations are provided that verifies the theoretical results. The availability of the proposed model has been validated with following observations: (1) the density of infected nodes in the proposed model drops to approximately 75% compared to the model in related literature; and (2) a higher density of KS is conductive to inhibition of virus diffusion.

  18. Functional analysis of replication determinantsin classical swine fever virus

    DEFF Research Database (Denmark)

    Hadsbjerg, Johanne

    boar with great socio-economic importance for countries, like Denmark, that have a significant trade in agricultural production. CSFV has, like other RNA viruses, a high mutation rate allowing the virus to adapt to changes in selection pressure. Hence obtaining a more thorough knowledge of sequence...... in the coding regions for NS2 and NS5B that restored the coding sequence to that of the parental field strain. When rescued viruses, containing mutant IRES elements, were introduced into pigs no induction of clinical disease could be observed and only limited levels of viral RNA were detected. In contrast......, inoculation with the parental virus caused similar clinical symptoms as that observed with the parental field strain. Analysing the adaptation of the viruses throughout the entire viralgenome during virus replication allowed a more comprehensive understanding of the virusproperties beyond what can...

  19. Survival of influenza A virus on contaminated student clothing.

    Science.gov (United States)

    Ikeda, Keiko; Tsujimoto, Kazuko; Suzuki, Yukiko; Koyama, Augustine Hajime

    2015-04-01

    The role of contaminated clothing in the transmission of influenza A virus during an epidemic period was investigated by examining the recovery of infectious influenza virus from experimentally virus-contaminated clothing, which had been subejected to routine wearing and washing for several months or years. The amount of infectious virus recovered from the nine types of clothing decreased with time and was shown to differ widely between clothing samples, when the contaminated clothing samples were maintained in uncovered glass Petri dishes in a safety cabinet under air blowing. These results indicate a dependence of virus transmissibility on the nature of the contaminated clothes. The difference in recovery was shown to have no significant correlation with the thickness or the materials of the clothing; however, a correlation was observed with the residual amount of water in the deposited virus preparation on the test clothing.

  20. Blue Tongue Virus

    African Journals Online (AJOL)

    Anupama

    bluetongue virus (BTV) infection cycle is initiated when the virus core is delivered into the cytoplasm of ... products available for the consumer market; therefore, .... BTV life cycle. BTV interacts with the target cell surface via VP2 timers which is then internalized in endosomes via a clathrin- dependent endocytosis pathway ...

  1. Viral Haemorrhagic Septicaemia Virus

    DEFF Research Database (Denmark)

    Olesen, Niels Jørgen; Skall, Helle Frank

    2013-01-01

    This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus.......This chapter covers the genetics (genotypes and serotypes), clinical signs, host species, transmission, prevalence, diagnosis, control and prevention of viral haemorrhagic septicaemia virus....

  2. Schmallenberg virus infection

    NARCIS (Netherlands)

    Wernike, K.; Elbers, A.R.W.; Beer, M.

    2015-01-01

    Since Schmallenberg virus, an orthobunyavirus of the Simbu serogroup, was identified near the German-Dutch border for the first time in late 2011 it has spread extremely quickly and caused a large epidemic in European livestock. The virus, which is transmitted by Culicoides biting midges, infects

  3. Avian influenza virus

    Science.gov (United States)

    Avian influenza virus (AIV) is type A influenza that is adapted to avian host species. Although the virus can be isolated from numerous avian species, the natural host reservoir species are dabbling ducks, shorebirds and gulls. Domestic poultry species (poultry being defined as birds that are rais...

  4. Surveillance of respiratory viruses.

    African Journals Online (AJOL)

    Respiratory virus isolates made at the National Institute for. Virology from 1982 to 1991 were studied. An active virus surveillance programme, 'viral watch', which recruits throat swab specimens from a network of monitoring centres - mainly in the Witwatersrand and Vereeniging area with one centre in Middelburg - that ...

  5. Viruses in reptiles.

    Science.gov (United States)

    Ariel, Ellen

    2011-09-21

    The etiology of reptilian viral diseases can be attributed to a wide range of viruses occurring across different genera and families. Thirty to forty years ago, studies of viruses in reptiles focused mainly on the zoonotic potential of arboviruses in reptiles and much effort went into surveys and challenge trials of a range of reptiles with eastern and western equine encephalitis as well as Japanese encephalitis viruses. In the past decade, outbreaks of infection with West Nile virus in human populations and in farmed alligators in the USA has seen the research emphasis placed on the issue of reptiles, particularly crocodiles and alligators, being susceptible to, and reservoirs for, this serious zoonotic disease. Although there are many recognised reptilian viruses, the evidence for those being primary pathogens is relatively limited. Transmission studies establishing pathogenicity and cofactors are likewise scarce, possibly due to the relatively low commercial importance of reptiles, difficulties with the availability of animals and permits for statistically sound experiments, difficulties with housing of reptiles in an experimental setting or the inability to propagate some viruses in cell culture to sufficient titres for transmission studies. Viruses as causes of direct loss of threatened species, such as the chelonid fibropapilloma associated herpesvirus and ranaviruses in farmed and wild tortoises and turtles, have re-focused attention back to the characterisation of the viruses as well as diagnosis and pathogenesis in the host itself.

  6. Hepatitis viruses overview

    African Journals Online (AJOL)

    Hepatitis is major cause of morbidity or mortality worldwide, particularly in the developing world. The major causes of infective hepatitis are hepatitis viruses. A, B, C, D or E. In the acute phase, there are no clinical features that can reliably differentiate between these viruses. Infection may be asymptomatic or can present as.

  7. Viruses and cancer

    NARCIS (Netherlands)

    Krul MRL; van Kranen HJ; van Kreijl CF; Steerenberg PA; van Loon AM

    1992-01-01

    The aim of this report is to review the relationship between viruses and the development of human cancer. It is currently known at least four viruses are directly implicated in the aetiology of human cancers and are involved in the induction of 15 to 20% of the worldwide tumor burden. Infection

  8. VIRUS IN COWPEA

    African Journals Online (AJOL)

    Cowpea breeding lines were infected with cucumber mosaic virus (CMV) by mechanical inoculation to investigate seed transmission rates for this virus. Transmission rates ranging from 0% to 6% were scored by symptom assessment. However, when cowpeas grown from seeds of infected mother plants were tested by.

  9. Virus separation using membranes.

    Science.gov (United States)

    Grein, Tanja A; Michalsky, Ronald; Czermak, Peter

    2014-01-01

    Industrial manufacturing of cell culture-derived viruses or virus-like particles for gene therapy or vaccine production are complex multistep processes. In addition to the bioreactor, such processes require a multitude of downstream unit operations for product separation, concentration, or purification. Similarly, before a biopharmaceutical product can enter the market, removal or inactivation of potential viral contamination has to be demonstrated. Given the complexity of biological solutions and the high standards on composition and purity of biopharmaceuticals, downstream processing is the bottleneck in many biotechnological production trains. Membrane-based filtration can be an economically attractive and efficient technology for virus separation. Viral clearance, for instance, of up to seven orders of magnitude has been reported for state of the art polymeric membranes under best conditions.This chapter summarizes the fundamentals of virus ultrafiltration, diafiltration, or purification with adsorptive membranes. In lieu of an impractical universally applicable protocol for virus filtration, application of these principles is demonstrated with two examples. The chapter provides detailed methods for production, concentration, purification, and removal of a rod-shaped baculovirus (Autographa californica M nucleopolyhedrovirus, about 40 × 300 nm in size, a potential vector for gene therapy, and an industrially important protein expression system) or a spherical parvovirus (minute virus of mice, 22-26 nm in size, a model virus for virus clearance validation studies).

  10. Blue Tongue Virus

    African Journals Online (AJOL)

    Anupama

    African Journal of Environmental Science and Technology Vol. 7(3), pp. 68-80, March ..... However, the disadvantages of attenuated BTV vaccines (Schultz ..... Sciences vol. 13, Nature Publishing Group, pp. 533–547. Mertens PPC, Diprose J (2004). The bluetongue virus core: a nano- scale transcription machine. Virus Res.

  11. Hepatitis E Virus

    African Journals Online (AJOL)

    Abstract. Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis in the developing world. It is a waterborne virus that can cause epidemics in the face of overcrowding and poor sanitation. Although the hepatitis illness is usually self-limiting, it has a high mortality in pregnant women and can become a ...

  12. Virus Dynamics and Evolution: Bridging Scales and Disciplines

    Directory of Open Access Journals (Sweden)

    Mary Poss

    2011-08-01

    Full Text Available Viruses have attracted the interest of researchers from multiple disciplines and have nucleated many productive and innovative collaborations. In part, this is because viruses so intimately associate with their hosts that decoupling host and virus biology is difficult, and virus-host interactions occur at multiple scales, from within cells to populations, each of which is intrinsically complex. As a consequence, ecologists, population biologists, evolutionary biologists, and researchers from quantitative fields, including mathematics, statistics, physics and computer science, make significant contributions to the field of virology. Our understanding of virus dynamics and evolution has substantially benefited from these multidisciplinary efforts. It is now common to see advanced phylogenetic reconstruction methods used to determine the origins of emergent viruses, to estimate the effect of natural selection on virus populations, and to assess virus population dynamics. Mathematical and statistical models that elucidate complex virus and host interactions in time and space at the molecular and population level are appearing more regularly in virology and biomedical journals. Massive quantities of data now available due to technological innovation in imaging, increased disease surveillance efforts, and novel approaches to determine social contact structure are changing approaches to study the dynamics and evolution of viral infections in heterogeneous environments. The next decade presents exciting new opportunities and challenges for the expanding field of researchers investigating dynamics of viral infections that will lead to innovation and new insight on virus interactions in both individual hosts and in populations. The compilation of articles in this Special Issue on “Virus Dynamics and Evolution” is comprised of reviews and primary research, summarized below, that provide new perspectives on virus interactions with host organisms through

  13. GB virus C: the good boy virus?

    Science.gov (United States)

    Bhattarai, Nirjal; Stapleton, Jack T.

    2012-01-01

    GB virus C (GBV-C) is a lymphotropic human virus discovered in 1995 that is related to hepatitis C virus (HCV). GBV-C infection has not been convincingly associated with any disease; however, several studies found an association between persistent GBV-C infection and improved survival in HIV-positive individuals. GBV-C infection modestly alters T cell homeostasis in vivo through various mechanisms, including modulation of chemokine and cytokine release and receptor expression, and by diminution of T cell activation, proliferation and apoptosis, all of which may contribute to improved HIV clinical outcomes. In vitro studies confirm these clinical observations and demonstrate an anti-HIV replication effect of GBV-C. This review summarizes existing data on potential mechanisms by which GBV-C interferes with HIV, and the research needed to capitalize on this epidemiological observation. PMID:22325031

  14. Structural significance of mechanical damage.

    Science.gov (United States)

    2012-05-01

    The letter transmits the Final Report for work completed under US DOT PHMSA Other Transaction Agreement (OTA) DTPH56-08-T-000011, Structural Significance of Mechanical Damage. The project was implemented to develop a detailed experimental database on...

  15. Significant New Alternatives Policy (SNAP)

    Science.gov (United States)

    These webpages provide information on EPA’s Significant New Alternatives Policy (SNAP) program which evaluates substitutes for ozone-depleting substances in major industrial use sectors. The SNAP program promotes a smooth transition to safer alternatives.

  16. Historical Significant Volcanic Eruption Locations

    Data.gov (United States)

    Department of Homeland Security — A significant eruption is classified as one that meets at least one of the following criteriacaused fatalities, caused moderate damage (approximately $1 million or...

  17. Astronomical Significance of Ancient Monuments

    Science.gov (United States)

    Simonia, I.

    2011-06-01

    Astronomical significance of Gokhnari megalithic monument (eastern Georgia) is considered. Possible connection of Amirani ancient legend with Gokhnari monument is discussed. Concepts of starry practicality and solar stations are proposed.

  18. Statistical Significance vs. Practical Significance: An Exploration through Health Education

    Science.gov (United States)

    Rosen, Brittany L.; DeMaria, Andrea L.

    2012-01-01

    The purpose of this paper is to examine the differences between statistical and practical significance, including strengths and criticisms of both methods, as well as provide information surrounding the application of various effect sizes and confidence intervals within health education research. Provided are recommendations, explanations and…

  19. Viruses of the Archaea

    DEFF Research Database (Denmark)

    Prangishvili,, David; Basta, Tamara; Garrett, Roger Antony

    2016-01-01

    Viruses infecting members of Archaea, the third domain of life, constitute an integral, yet unique part of the virosphere. Many of these viruses, specifically the species that infect hyperthermophilic hosts, display morphotypes – for example, bottle shaped, spindle shaped, droplet shaped, coil...... shaped, bacilliform – not known to be associated with the other two cellular domains, Bacteria and Eukarya. The distinctiveness of the hyperthermophilic archaeal viruses extends to their genome sequences: a large majority of the predicted genes yield no sequence matches in public databases and encode...... proteins with exceptional structures and unknown functions. Moreover, the ways in which these viruses interact with their hosts are also unique, as indicated by a unique virion egress mechanism, which involves formation of pyramidal portals on the cell surface. Some viruses that infect extremely halophilic...

  20. BS-virus-finder

    DEFF Research Database (Denmark)

    Gao, Shengjie; Hu, Xuesong; Xu, Fengping

    2018-01-01

    Background: DNA methylation plays a key role in the regulation of gene expression and carcinogenesis. Bisulfite sequencing studies mainly focus on calling SNP, DMR, and ASM. Until now, only a few software tools focus on virus integration using bisulfite sequencing data. Findings: We have developed...... a new and easy-to-use software tool, named BS-virus-finder (BSVF, RRID:SCR_015727), to detect viral integration breakpoints in whole human genomes. The tool is hosted at https://github.com/BGI-SZ/BSVF. Conclusions: BS-virus-finder demonstrates high sensitivity and specificity. It is useful in epigenetic...... studies and to reveal the relationship between viral integration and DNA methylation. BS-virus-finder is the first software tool to detect virus integration loci by using bisulfite sequencing data....

  1. Mayaro virus proteins

    Directory of Open Access Journals (Sweden)

    J. M. S. Mezencio

    1993-06-01

    Full Text Available Mayaro virus was grown in BHK-21 cells and purified by centrifugation in a potassium-tartrate gradient (5-50%. The electron microscopy analyses of the purified virus showed an homogeneous population of enveloped particles with 69 ñ 2.3 nm in diameter. Three structural virus proteins were identified and designated pl, p2 and p3. Their average molecular weight were p1, 54 KDa; p2, 50 KDa and p3, 34 KDa. In Mayaro virus infected. Aedes albopictus cells and in BHK-21 infected cells we detected six viral proteins, in wich three of them are the structural virus proteins and the other three were products from processing of precursors of viral proteins, whose molecular weights are 62 KDa, 64 KDa and 110 KDa. The 34 KDa protein was the first viral protein sinthesized at 5 hours post-infection in both cell lines studied.

  2. Collection of Viable Aerosolized Influenza Virus and Other Respiratory Viruses in a Student Health Care Center through Water-Based Condensation Growth.

    Science.gov (United States)

    Pan, Maohua; Bonny, Tania S; Loeb, Julia; Jiang, Xiao; Lednicky, John A; Eiguren-Fernandez, Arantzazu; Hering, Susanne; Fan, Z Hugh; Wu, Chang-Yu

    2017-01-01

    The dynamics and significance of aerosol transmission of respiratory viruses are still controversial, for the major reasons that virus aerosols are inefficiently collected by commonly used air samplers and that the collected viruses are inactivated by the collection method. Without knowledge of virus viability, infection risk analyses lack accuracy. This pilot study was performed to (i) determine whether infectious (viable) respiratory viruses in aerosols could be collected from air in a real world environment by the viable virus aerosol sampler (VIVAS), (ii) compare and contrast the efficacy of the standard bioaerosol sampler, the BioSampler, with that of the VIVAS for the collection of airborne viruses in a real world environment, and (iii) gain insights for the use of the VIVAS for respiratory virus sampling. The VIVAS operates via a water vapor condensation process to enlarge aerosolized virus particles to facilitate their capture. A variety of viable human respiratory viruses, including influenza A H1N1 and H3N2 viruses and influenza B viruses, were collected by the VIVAS located at least 2 m from seated patients, during a late-onset 2016 influenza virus outbreak. Whereas the BioSampler when operated following our optimized parameters also collected virus aerosols, it was nevertheless overall less successful based on a lower frequency of virus isolation in most cases. This side-by-side comparison highlights some limitations of past studies based on impingement-based sampling, which may have generated false-negative results due to either poor collection efficiency and/or virus inactivation due to the collection process. IMPORTANCE The significance of virus aerosols in the natural transmission of respiratory diseases has been a contentious issue, primarily because it is difficult to collect or sample virus aerosols using currently available air sampling devices. We tested a new air sampler based on water vapor condensation for efficient sampling of viable

  3. Phylogenetic relationships of closely related potyviruses infecting sweet potato determined by genomic characterization of Sweet potato virus G and Sweet potato virus 2.

    Science.gov (United States)

    Li, Fan; Xu, Donglin; Abad, Jorge; Li, Ruhui

    2012-08-01

    Complete nucleotide sequences of Sweet potato virus G (SPVG) and Sweet potato virus 2 (SPV2) were determined to be 10,800 and 10,731 nucleotides, respectively, excluding the 3'-poly(A) tail. Their genomic organizations are typical of potyviruses, encoding a polyprotein which is likely cleaved into 10 mature proteins by three viral proteinases. Conserved motifs of orthologous proteins of viruses in the genus Potyvirus are found in corresponding positions of both viruses. Pairwise comparisons of individual protein sequences of the two viruses with those of 78 other potyviruses show that P1 protein and coat protein (CP) of both viruses are significantly large, with the SPVG CP as the largest among the all the known species of the genus Potyvirus. The extended N-terminal region of the P1 protein is conserved in the potyviruses and ipomovirus infecting sweet potato. A novel ORF, PISPO, is identified within the P1 region of SPVG, SPV2, Sweet potato feathery mottle virus (SPFMV), and Sweet potato virus C (SPVC). The C-terminal half of CP is highly conserved among SPFMV, SPVC, SPVG, SPV2, and Sweet potato virus-Zimbabwe. Phylogenetic analysis based on the deduced CP amino acid sequences supports the view that these five viruses are grouped together in a SPFMV lineage. The analysis also reveals that Sweet potato virus Y and Ipomoea vein mosaic virus are grouped with SPV2 as one species, and these two viruses should be consolidated with SPV2.

  4. Serological profiles of Herpes simplex virus type 2 among HIV ...

    African Journals Online (AJOL)

    Herpes simplex virus type-2 (HSV-2) is the major cause of genital ulcer diseases (GUD) consequently a significant factor for the acquisition and transmission of human immunodeficiency virus (HIV). Despite its importance there is paucity of data regarding the magnitude of HSV-2 in non-HIV infected population in ...

  5. Variability or conservation of hepatitis C virus hypervariable region 1 ...

    Indian Academy of Sciences (India)

    Unknown

    The hypervariable region 1 (HVR1) of the E2 protein of hepatitis C virus (HCV) is highly heterogeneous in its primary sequence and is responsible for significant inter- and intra-individual variation of the infecting virus, which may represent an important pathogenetic mechanism leading to immune escape and persistent ...

  6. Virus - vector relationships in the transmission of tospoviruses

    NARCIS (Netherlands)

    Wijkamp, I.

    1995-01-01

    Tomato spotted wilt virus (TSWV), member of the genus Tospovirus within the family Bunyaviridae, ranks among the top ten of economically most important plant viruses. Tospoviruses cause significant yield losses in agricultural crops such as tomato,

  7. Serological Evidence Of Rabies Virus Infection Of Slaughter Camels ...

    African Journals Online (AJOL)

    A survey of antibodies against rabies virus was carried out in camels imported for slaughter at Maiduguri municipal abattoir in Borno State, Nigeria. Out of the 256 camel sera tested, 18 (7%) had complement-fixing antibody against rabies virus antigen. Significant difference (P<0.05) in antibody prevalence was observed ...

  8. the viruses and virus diseases of cassava in Africa

    African Journals Online (AJOL)

    Crops that are propagated vegetatively are viruses or putative viruses have been isolated particularly prone to virus ... eight viruses known to infect are selected and used for repeated cycles of crop cassava in Africa and on the diseases they cause. ... vein mosaic pararetrovirus. Cassava Colombian symptomless potexvirus.

  9. Metagenomic analysis of RNA viruses in a fresh water lake.

    Directory of Open Access Journals (Sweden)

    Appolinaire Djikeng

    Full Text Available Freshwater lakes and ponds present an ecological interface between humans and a variety of host organisms. They are a habitat for the larval stage of many insects and may serve as a medium for intraspecies and interspecies transmission of viruses such as avian influenza A virus. Furthermore, freshwater bodies are already known repositories for disease-causing viruses such as Norwalk Virus, Coxsackievirus, Echovirus, and Adenovirus. While RNA virus populations have been studied in marine environments, to this date there has been very limited analysis of the viral community in freshwater. Here we present a survey of RNA viruses in Lake Needwood, a freshwater lake in Maryland, USA. Our results indicate that just as in studies of other aquatic environments, the majority of nucleic acid sequences recovered did not show any significant similarity to known sequences. The remaining sequences are mainly from viral types with significant similarity to approximately 30 viral families. We speculate that these novel viruses may infect a variety of hosts including plants, insects, fish, domestic animals and humans. Among these viruses we have discovered a previously unknown dsRNA virus closely related to Banna Virus which is responsible for a febrile illness and is endemic to Southeast Asia. Moreover we found multiple viral sequences distantly related to Israeli Acute Paralysis virus which has been implicated in honeybee colony collapse disorder. Our data suggests that due to their direct contact with humans, domestic and wild animals, freshwater ecosystems might serve as repositories of a wide range of viruses (both pathogenic and non-pathogenic and possibly be involved in the spread of emerging and pandemic diseases.

  10. Metagenomic analysis of RNA viruses in a fresh water lake.

    Science.gov (United States)

    Djikeng, Appolinaire; Kuzmickas, Ryan; Anderson, Norman G; Spiro, David J

    2009-09-29

    Freshwater lakes and ponds present an ecological interface between humans and a variety of host organisms. They are a habitat for the larval stage of many insects and may serve as a medium for intraspecies and interspecies transmission of viruses such as avian influenza A virus. Furthermore, freshwater bodies are already known repositories for disease-causing viruses such as Norwalk Virus, Coxsackievirus, Echovirus, and Adenovirus. While RNA virus populations have been studied in marine environments, to this date there has been very limited analysis of the viral community in freshwater. Here we present a survey of RNA viruses in Lake Needwood, a freshwater lake in Maryland, USA. Our results indicate that just as in studies of other aquatic environments, the majority of nucleic acid sequences recovered did not show any significant similarity to known sequences. The remaining sequences are mainly from viral types with significant similarity to approximately 30 viral families. We speculate that these novel viruses may infect a variety of hosts including plants, insects, fish, domestic animals and humans. Among these viruses we have discovered a previously unknown dsRNA virus closely related to Banna Virus which is responsible for a febrile illness and is endemic to Southeast Asia. Moreover we found multiple viral sequences distantly related to Israeli Acute Paralysis virus which has been implicated in honeybee colony collapse disorder. Our data suggests that due to their direct contact with humans, domestic and wild animals, freshwater ecosystems might serve as repositories of a wide range of viruses (both pathogenic and non-pathogenic) and possibly be involved in the spread of emerging and pandemic diseases.

  11. Significance analysis of prognostic signatures.

    Directory of Open Access Journals (Sweden)

    Andrew H Beck

    Full Text Available A major goal in translational cancer research is to identify biological signatures driving cancer progression and metastasis. A common technique applied in genomics research is to cluster patients using gene expression data from a candidate prognostic gene set, and if the resulting clusters show statistically significant outcome stratification, to associate the gene set with prognosis, suggesting its biological and clinical importance. Recent work has questioned the validity of this approach by showing in several breast cancer data sets that "random" gene sets tend to cluster patients into prognostically variable subgroups. This work suggests that new rigorous statistical methods are needed to identify biologically informative prognostic gene sets. To address this problem, we developed Significance Analysis of Prognostic Signatures (SAPS which integrates standard prognostic tests with a new prognostic significance test based on stratifying patients into prognostic subtypes with random gene sets. SAPS ensures that a significant gene set is not only able to stratify patients into prognostically variable groups, but is also enriched for genes showing strong univariate associations with patient prognosis, and performs significantly better than random gene sets. We use SAPS to perform a large meta-analysis (the largest completed to date of prognostic pathways in breast and ovarian cancer and their molecular subtypes. Our analyses show that only a small subset of the gene sets found statistically significant using standard measures achieve significance by SAPS. We identify new prognostic signatures in breast and ovarian cancer and their corresponding molecular subtypes, and we show that prognostic signatures in ER negative breast cancer are more similar to prognostic signatures in ovarian cancer than to prognostic signatures in ER positive breast cancer. SAPS is a powerful new method for deriving robust prognostic biological signatures from clinically

  12. Cryptoporus volvatus extract inhibits influenza virus replication in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Li Gao

    Full Text Available Influenza virus is the cause of significant morbidity and mortality, posing a serious health threat worldwide. Here, we evaluated the antiviral activities of Cryptoporus volvatus extract on influenza virus infection. Our results demonstrated that the Cryptoporus volvatus extract inhibited different influenza virus strain replication in MDCK cells. Time course analysis indicated that the extract exerted its inhibition at earlier and late stages in the replication cycle of influenza virus. Subsequently, we confirmed that the extract suppressed virus internalization into and released from cells. Moreover, the extract significantly reduced H1N1/09 influenza virus load in lungs and dramatically decreased lung lesions in mice. And most importantly, the extract protected mice from lethal challenge with H1N1/09 influenza virus. Our results suggest that the Cryptoporus volvatus extract could be a potential candidate for the development of a new anti-influenza virus therapy.

  13. Cryptoporus volvatus Extract Inhibits Influenza Virus Replication In Vitro and In Vivo

    Science.gov (United States)

    Si, Jianyong; Liu, Jinhua; Sun, Guibo; Sun, Xiaobo; Cao, Li

    2014-01-01

    Influenza virus is the cause of significant morbidity and mortality, posing a serious health threat worldwide. Here, we evaluated the antiviral activities of Cryptoporus volvatus extract on influenza virus infection. Our results demonstrated that the Cryptoporus volvatus extract inhibited different influenza virus strain replication in MDCK cells. Time course analysis indicated that the extract exerted its inhibition at earlier and late stages in the replication cycle of influenza virus. Subsequently, we confirmed that the extract suppressed virus internalization into and released from cells. Moreover, the extract significantly reduced H1N1/09 influenza virus load in lungs and dramatically decreased lung lesions in mice. And most importantly, the extract protected mice from lethal challenge with H1N1/09 influenza virus. Our results suggest that the Cryptoporus volvatus extract could be a potential candidate for the development of a new anti-influenza virus therapy. PMID:25437846

  14. The evolution of down-scale virus filtration equipment for virus clearance studies.

    Science.gov (United States)

    Wieser, Andreas; Berting, Andreas; Medek, Christian; Poelsler, Gerhard; Kreil, Thomas R

    2015-03-01

    The role of virus filtration in assuring the safety of biopharmaceutical products has gained importance in recent years. This is due to the fundamental advantages of virus filtration, which conceptually can remove all pathogens as long as their size is larger than the biomolecule of commercial interest, while at the same time being neutral to the biological activity of biopharmaceutical compound(s). Major progress has been made in the development of adequate filtration membranes that can remove even smaller viruses, or possibly even all. Establishing down-scaled models for virus clearance studies that are fully equivalent with respect to operating parameters at manufacturing scale is a continuing challenge. This is especially true for virus filtration procedures where virus clearance studies at small-scale determine the operating parameters, which can be used at manufacturing scale. This has limited volume-to-filter-area-ratios, with significant impact on process economics. An advanced small-scale model of virus filtration, which allows the investigation of the full complexity of these processes, is described here. It includes the automated monitoring and control of all process parameters, as well as an electronic data acquisition system, which is fully compliant with current regulatory requirements for electronic records in a pharmaceutical environment. © 2014 Wiley Periodicals, Inc.

  15. Impact of aphid alarm pheromone release on virus transmission efficiency: When pest control strategy could induce higher virus dispersion.

    Science.gov (United States)

    Lin, Fang-Jing; Bosquée, Emilie; Liu, Ying-Jie; Chen, Ju-Lian; Yong, Liu; Francis, Frédéric

    2016-09-01

    Aphids cause serious damages to crops not only by tacking sap but also by transmitting numerous viruses. To develop biological control, the aphid alarm pheromone, namely E-β-farnesene (EβF), has been demonstrated to be efficient to repel aphids and as attract beneficials, making it a potential tool to control aphid pests. Considering aphids also as virus vectors, changes of their behavior could also interfere with the virus acquisition and transmission process. Here, a combination of two aphid species and two potato virus models were selected to test the influence of EβF release on aphid and virus dispersion under laboratory conditions. EβF release was found to significantly decrease the population of Myzus persicae and Macrosiphum euphorbiae around the infochemical releaser but simultaneously also increasing the dispersal of Potato Virus Y (PVY). At the opposite, no significant difference for Potato Leaf Roll Virus (PLRV) transmission efficiency was observed with similar aphid alarm pheromone releases for none of the aphid species. These results provide some support to carefully consider infochemical releasers not only for push-pull strategy and pest control but also to include viral disease in a the plant protection to aphids as they are also efficient virus vectors. Impact of aphid kinds and transmission mechanisms will be discussed according to the large variation found between persistent and non persistent potato viruses and interactions with aphids and related infochemicals. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Metagenomic analyses of novel viruses and plasmids from a cultured environmental sample of hyperthermophilic neutrophiles

    DEFF Research Database (Denmark)

    Garrett, Roger Antony; Prangishvili, David; Shah, Shiraz Ali

    2010-01-01

    ), and derive apparently from archaeal viruses HAV1 and HAV2. Genomic DNA was obtained from samples enriched in filamentous and tadpole-shaped virus-like particles respectively. They yielded few significant matches in public sequence databases reinforcing, further, the wide diversity of archaeal viruses...

  17. A Tomato necrotic dwarf virus isolate from Datura with poor transmissibility by the whitefly, Bemisia tabaci

    Science.gov (United States)

    Tomato necrotic dwarf virus (ToNDV); genus Torradovirus, is a whitefly-transmitted virus that caused significant losses for tomato production in the Imperial Valley of California during the 1980s. The virus causes severe stunting, dwarfing of leaves, foliar and fruit necrosis, and greatly reduced f...

  18. Significance evaluation in factor graphs

    DEFF Research Database (Denmark)

    Madsen, Tobias; Hobolth, Asger; Jensen, Jens Ledet

    2017-01-01

    Background Factor graphs provide a flexible and general framework for specifying probability distributions. They can capture a range of popular and recent models for analysis of both genomics data as well as data from other scientific fields. Owing to the ever larger data sets encountered...... in genomics and the multiple-testing issues accompanying them, accurate significance evaluation is of great importance. We here address the problem of evaluating statistical significance of observations from factor graph models. Results Two novel numerical approximations for evaluation of statistical...... significance are presented. First a method using importance sampling. Second a saddlepoint approximation based method. We develop algorithms to efficiently compute the approximations and compare them to naive sampling and the normal approximation. The individual merits of the methods are analysed both from...

  19. Detection of varicella-zoster virus and herpes simplex virus by the polymerase chain reaction with degenerate primers

    NARCIS (Netherlands)

    Jacobs, J.J.L.; Folkers, E.; Vreeswijk, J.

    1999-01-01

    Varicella-zoster virus (VZV) and herpes simplex virus (HSV) are human pathogens of significance involved in multiple diseases with either typical or atypical clinical features. In neonates and immunocompromised patients these alphaherpesviruses may cause life-threatening diseases such as

  20. Intramuscular immunization of mice with live influenza virus is more immunogenic and offers greater protection than immunization with inactivated virus

    Directory of Open Access Journals (Sweden)

    Eichelberger Maryna C

    2011-05-01

    Full Text Available Abstract Background Influenza virus continues to cause significant hospitalization rates in infants and young children. A 2-dose regime of trivalent inactivated vaccine is required to generate protective levels of hemagglutination inhibiting (HAI antibodies. A vaccine preparation with enhanced immunogenicity is therefore desirable. Methods Mice were inoculated intramuscularly (IM with live and inactivated preparations of A/Wisconsin/67/2005 (H3N2. Serum cytokine levels, hemagglutinin (HA-specific antibody responses and nucleoprotein (NP-specific CD8+ T cell responses were compared between vaccinated groups, as well as to responses measured after intranasal infection. The protective efficacy of each vaccine type was compared by measuring virus titers in the lungs and weight loss of mice challenged intranasally with a heterosubtypic virus, A/PR/8/34 (H1N1. Results Intramuscular administration of live virus resulted in greater amounts of IFN-α, IL-12 and IFN-γ, HA-specific antibodies, and virus-specific CD8+ T cells, than IM immunization with inactivated virus. These increases corresponded with the live virus vaccinated group having significantly less weight loss and less virus in the lungs on day 7 following challenge with a sublethal dose of a heterosubtypic virus. Conclusions Inflammatory cytokines, antibody titers to HA and CD8+ T cell responses were greater to live than inactivated virus delivered IM. These increased responses correlated with greater protection against heterosubtypic virus challenge, suggesting that intramuscular immunization with live influenza virus may be a practical means to increase vaccine immunogenicity and to broaden protection in pediatric populations.

  1. HCV Virus and Lymphoid Neoplasms

    Directory of Open Access Journals (Sweden)

    Yutaka Tsutsumi

    2011-01-01

    Full Text Available Hepatitis C virus (HCV is one of the viruses known to cause hepatic cancer. HCV is also believed to be involved in malignant lymphoma. In this paper, we investigated characteristics of malignant lymphoma cases that were anti-HCV antibody (HCV-Ab positive. We were able to perform pathological examinations on 13 out of 14 HCV-positive cases. Of these, lymphoid tissues of 10 stained positive for HCV-Ab. There was no significant correlation between the degree of HCV staining and the rate of recurrence or resistance to treatment. However, there did appear to be a consistent decrease in the amount of HCV-RNA between pre- and posttreatment among HCV-Ab-positive cases; that is, treatment-resistant cases that exhibited resistance from the first treatment and recurrent cases more frequently had a higher HCV level at treatment termination compared to the pretreatment level. This suggests that the HCV virus either accelerates oncogenesis by direct interaction with B cells or indirectly affects lymphoma prognosis.

  2. Computer Viruses: Pathology and Detection.

    Science.gov (United States)

    Maxwell, John R.; Lamon, William E.

    1992-01-01

    Explains how computer viruses were originally created, how a computer can become infected by a virus, how viruses operate, symptoms that indicate a computer is infected, how to detect and remove viruses, and how to prevent a reinfection. A sidebar lists eight antivirus resources. (four references) (LRW)

  3. Molecular characterization of Lelystad virus

    NARCIS (Netherlands)

    Meulenberg, J.J.M.; Petersen-den Besten, A.; Kluyver, de E.; Nieuwstadt, van A.; Wensvoort, G.; Moormann, R.J.M.

    1997-01-01

    Lelystad virus (LV), the prototype of porcine reproductive respiratory syndrome virus, is a small enveloped virus, containing a positive strand RNA genome of 15 kb. LV is tentatively classified in the family Arteriviridae, which consists of lactate dehydrogenase-elevating virus (LDV), equine

  4. The historical significance of oak

    Science.gov (United States)

    J. V. Thirgood

    1971-01-01

    A brief history of the importance of oak in Europe, contrasting the methods used in France and Britain to propagate the species and manage the forests for continued productivity. The significance of oak as a strategic resource during the sailing-ship era is stressed, and mention is made of the early development of oak management in North America. The international...

  5. Synthesis of Nucleoside Analogues with Potential Antiviral Activity against Negative Strand RNA Virus Targets

    Science.gov (United States)

    1989-11-01

    ye Paramyxovirus Human parainfluenza , mumps Morbillivirus Measles, Rinderpest (cattle) 9 canine distemper viruses Pneumovirus Respiratory syncytial...significant effect on man include Rabies virus1 0 and Vesicular Stomatitus virus (VSV) in the Americas and Bovine Ephemeral Fever virus in Australasia. Of the...structurally related to neplanocin A, namely 9-(trans-2’,trans-3’-dihydroxycyclo- pent-4’-enyl) derivatives, 4 and 5, are potent inhibitors of bovine liver

  6. Characterization of Influenza Virus-Induced Leukocyte Adherence to Human Umbilical Vein Endothelial Cell Monolayers

    Science.gov (United States)

    1993-07-01

    with other viruses. HL-60 cell adherence to endothelial cell virus type A, which did not infect human venous or bovine monolayers was modulated by...LEUCOCYTE ADHERENC:E TO [NDOTIIELIL (FS1% A. B reawsd on parainfluenza virus-infected airway epithelial Poiy-iiysine Codled IPLC) Wells PLC.Wells cells...an antibody against ICAN1- I has no significant effect PLC Wells Virus on parainfluenza -induced neutrophil adherence (58). In 25 *HSV-intected HUVEC

  7. Probiotics in respiratory virus infections.

    Science.gov (United States)

    Lehtoranta, L; Pitkäranta, A; Korpela, R

    2014-08-01

    Viral respiratory infections are the most common diseases in humans. A large range of etiologic agents challenge the development of efficient therapies. Research suggests that probiotics are able to decrease the risk or duration of respiratory infection symptoms. However, the antiviral mechanisms of probiotics are unclear. The purpose of this paper is to review the current knowledge on the effects of probiotics on respiratory virus infections and to provide insights on the possible antiviral mechanisms of probiotics. A PubMed and Scopus database search was performed up to January 2014 using appropriate search terms on probiotic and respiratory virus infections in cell models, in animal models, and in humans, and reviewed for their relevance. Altogether, thirty-three clinical trials were reviewed. The studies varied highly in study design, outcome measures, probiotics, dose, and matrices used. Twenty-eight trials reported that probiotics had beneficial effects in the outcome of respiratory tract infections (RTIs) and five showed no clear benefit. Only eight studies reported investigating viral etiology from the respiratory tract, and one of these reported a significant decrease in viral load. Based on experimental studies, probiotics may exert antiviral effects directly in probiotic-virus interaction or via stimulation of the immune system. Although probiotics seem to be beneficial in respiratory illnesses, the role of probiotics on specific viruses has not been investigated sufficiently. Due to the lack of confirmatory studies and varied data available, more randomized, double-blind, and placebo-controlled trials in different age populations investigating probiotic dose response, comparing probiotic strains/genera, and elucidating the antiviral effect mechanisms are necessary.

  8. Phylogenetic analysis of Melon chlorotic leaf curl virus from Guatemala: Another emergent species in the Squash leaf curl virus clade

    KAUST Repository

    Brown, J.K.

    2011-06-01

    The genome of a new bipartite begomovirus Melon chlorotic leaf curl virus from Guatemala (MCLCuV-GT) was cloned and the genome sequence was determined. The virus causes distinct symptoms on melons that were not previously observed in melon crops in Guatemala or elsewhere. Phylogenetic analysis of MCLCuV-GT and begomoviruses infecting cucurbits and other host plant species indicated that its closest relative was MCLCuV from Costa Rica (MCLCuV-CR). The DNA-A components of two isolates shared 88.8% nucleotide identity, making them strains of the same species. Further, both MCLCuV-GT and MCLCuV-CR grouped with other Western Hemisphere cucurbit-infecting species in the SLCV-clade making them the most southerly cucurbit-infecting members of the clade to date. Although the common region of the cognate components of MCLCuV-GT and MCLCuV-CR, shared similar to 96.3% nucleotide identity. While DNA-A and DNA-B components of MCLCuV-GT were less than 86% nucleotide identity with the respective DNAA and DNA-B common regions of MCLCuV-CR. The late viral genes of the two strains shared the least nt identity (<88%) while their early genes shared the highest nt identity (>90%). The collective evidence suggests that these two strains of MCLCuV are evolutionarily divergent owing in part to recombination, but also due to the accumulation of a substantial number of mutations. In addition they are differentially host-adapted, as has been documented for other cucurbit-infecting, bean-adapted, species in the SLCV clade. (C) 2011 Elsevier B.V. All rights reserved.

  9. Influenza virus isolation.

    Science.gov (United States)

    Krauss, Scott; Walker, David; Webster, Robert G

    2012-01-01

    The isolation of influenza viruses is important for the diagnosis of respiratory diseases in lower animals and humans, for the detection of the infecting agent in surveillance programs, and is an essential element in the development and production of vaccine. Since influenza is caused by a zoonotic virus it is necessary to do surveillance in the reservoir species (aquatic waterfowls), intermediate hosts (quails, pigs), and in affected mammals including humans. Two of the hemagglutinin (HA) subtypes of influenza A viruses (H5 and H7) can evolve into highly pathogenic (HP) strains for gallinaceous poultry; some HP H5 and H7 strains cause lethal infection of humans. In waterfowls, low pathogenic avian influenza (LPAI) isolates are obtained primarily from the cloaca (or feces); in domestic poultry, the virus is more often recovered from the respiratory tract than from cloacal samples; in mammals, the virus is most often isolated from the respiratory tract, and in cases of high pathogenic avian influenza (HPAI) from the blood and internal organs of infected birds. Virus isolation procedures are performed by inoculation of clinical specimens into embryonated eggs (primarily chicken eggs) or onto a variety of primary or continuous tissue culture systems. Successful isolation of influenza virus depends on the quality of the sample and matching the appropriate culture method to the sample type.

  10. Ocular tropism of respiratory viruses.

    Science.gov (United States)

    Belser, Jessica A; Rota, Paul A; Tumpey, Terrence M

    2013-03-01

    Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism.

  11. Oncolytic viruses in cancer therapy.

    Science.gov (United States)

    Vähä-Koskela, Markus J V; Heikkilä, Jari E; Hinkkanen, Ari E

    2007-09-08

    Oncolytic virotherapy is a promising form of gene therapy for cancer, employing nature's own agents to find and destroy malignant cells. The purpose of this review is to provide an introduction to this very topical field of research and to point out some of the current observations, insights and ideas circulating in the literature. We have strived to acknowledge as many different oncolytic viruses as possible to give a broader picture of targeting cancer using viruses. Some of the newest additions to the panel of oncolytic viruses include the avian adenovirus, foamy virus, myxoma virus, yaba-like disease virus, echovirus type 1, bovine herpesvirus 4, Saimiri virus, feline panleukopenia virus, Sendai virus and the non-human coronaviruses. Although promising, virotherapy still faces many obstacles that need to be addressed, including the emergence of virus-resistant tumor cells.

  12. Enhanced light microscopy visualization of virus particles from Zika virus to filamentous ebolaviruses.

    Directory of Open Access Journals (Sweden)

    George G Daaboul

    Full Text Available Light microscopy is a powerful tool in the detection and analysis of parasites, fungi, and prokaryotes, but has been challenging to use for the detection of individual virus particles. Unlabeled virus particles are too small to be visualized using standard visible light microscopy. Characterization of virus particles is typically performed using higher resolution approaches such as electron microscopy or atomic force microscopy. These approaches require purification of virions away from their normal millieu, requiring significant levels of expertise, and can only enumerate small numbers of particles per field of view. Here, we utilize a visible light imaging approach called Single Particle Interferometric Reflectance Imaging Sensor (SP-IRIS that allows automated counting and sizing of thousands of individual virions. Virions are captured directly from complex solutions onto a silicon chip and then detected using a reflectance interference imaging modality. We show that the use of different imaging wavelengths allows the visualization of a multitude of virus particles. Using Violet/UV illumination, the SP-IRIS technique is able to detect individual flavivirus particles (~40 nm, while green light illumination is capable of identifying and discriminating between vesicular stomatitis virus and vaccinia virus (~360 nm. Strikingly, the technology allows the clear identification of filamentous infectious ebolavirus particles and virus-like particles. The ability to differentiate and quantify unlabeled virus particles extends the usefulness of traditional light microscopy and can be embodied in a straightforward benchtop approach allowing widespread applications ranging from rapid detection in biological fluids to analysis of virus-like particles for vaccine development and production.

  13. Cowpea viruses: Effect of single and mixed infections on symptomatology and virus concentration

    Directory of Open Access Journals (Sweden)

    Nsa Imade Y

    2007-09-01

    Full Text Available Abstract Natural multiple viral infections of cultivated cowpeas have been reported in Nigeria. In this study, three Nigerian commercial cowpea cultivars ("Olo 11", "Oloyin" and "White" and two lines from the IITA (IT86D- 719 and TVU 76 were mechanically inoculated with Cowpea aphid-borne mosaic virus (CABMV, Bean southern mosaic virus (SBMV and Cowpea mottle virus (CMeV singly, as well as in all possible combinations at 10, 20 and 30 days after planting (DAP. Samples of leaves or stems were collected at 10, 20 and 30 days after inoculation (DAI and analyzed for relative virus concentration by Enzyme-Linked Immunosrbent Assay. All the cultivars and lines {CVS/L} were susceptible to the viruses but the commercial CVS showed more severe symptoms and had relatively higher viral concentration. In single virus infections, CABMV which induced the most severe symptoms had absorbance values (at 405 nm of 0.11 to 0.46 while SBMV and CMeV which induced moderate symptoms had virus titre of 0.74 to 1.99 and 0.11 to 0.90 respectively. Plants inoculated 10 DAP had significantly higher virus concentration than those inoculated 30 DAP. In mixed infections involving CABMV (10 DAP apical necrosis and death were observed in commercial cultivars "Olo 11" and "White". Enhancement of CMeV titers were observed in plants infected with CMeV + CABMV. Multiple viral infections of cowpeas may result in complete yield loss, hence, the availability of seeds of cultivars with a high level of multiple virus resistance is recommended as a means of control.

  14. Significance evaluation in factor graphs

    DEFF Research Database (Denmark)

    Madsen, Tobias; Hobolth, Asger; Jensen, Jens Ledet

    2017-01-01

    in genomics and the multiple-testing issues accompanying them, accurate significance evaluation is of great importance. We here address the problem of evaluating statistical significance of observations from factor graph models. Results Two novel numerical approximations for evaluation of statistical......Background Factor graphs provide a flexible and general framework for specifying probability distributions. They can capture a range of popular and recent models for analysis of both genomics data as well as data from other scientific fields. Owing to the ever larger data sets encountered...... a theoretical viewpoint and with simulations. A guideline for choosing between the normal approximation, saddle-point approximation and importance sampling is also provided. Finally, the applicability of the methods is demonstrated with examples from cancer genomics, motif-analysis and phylogenetics...

  15. Viruses in reptiles

    Directory of Open Access Journals (Sweden)

    Ariel Ellen

    2011-09-01

    Full Text Available Abstract The etiology of reptilian viral diseases can be attributed to a wide range of viruses occurring across different genera and families. Thirty to forty years ago, studies of viruses in reptiles focused mainly on the zoonotic potential of arboviruses in reptiles and much effort went into surveys and challenge trials of a range of reptiles with eastern and western equine encephalitis as well as Japanese encephalitis viruses. In the past decade, outbreaks of infection with West Nile virus in human populations and in farmed alligators in the USA has seen the research emphasis placed on the issue of reptiles, particularly crocodiles and alligators, being susceptible to, and reservoirs for, this serious zoonotic disease. Although there are many recognised reptilian viruses, the evidence for those being primary pathogens is relatively limited. Transmission studies establishing pathogenicity and cofactors are likewise scarce, possibly due to the relatively low commercial importance of reptiles, difficulties with the availability of animals and permits for statistically sound experiments, difficulties with housing of reptiles in an experimental setting or the inability to propagate some viruses in cell culture to sufficient titres for transmission studies. Viruses as causes of direct loss of threatened species, such as the chelonid fibropapilloma associated herpesvirus and ranaviruses in farmed and wild tortoises and turtles, have re-focused attention back to the characterisation of the viruses as well as diagnosis and pathogenesis in the host itself. 1. Introduction 2. Methods for working with reptilian viruses 3. Reptilian viruses described by virus families 3.1. Herpesviridae 3.2. Iridoviridae 3.2.1 Ranavirus 3.2.2 Erythrocytic virus 3.2.3 Iridovirus 3.3. Poxviridae 3.4. Adenoviridae 3.5. Papillomaviridae 3.6. Parvoviridae 3.7. Reoviridae 3.8. Retroviridae and inclusion body disease of Boid snakes 3.9. Arboviruses 3.9.1. Flaviviridae 3

  16. Zika virus in Asia

    Directory of Open Access Journals (Sweden)

    Veasna Duong

    2017-01-01

    Full Text Available Zika virus (ZIKV is an emerging mosquito-borne virus that was first isolated from a sentinel rhesus monkey in the Zika Forest in Uganda in 1947. In Asia, the virus was isolated in Malaysia from Aedes aegypti mosquitoes in 1966, and the first human infections were reported in 1977 in Central Java, Indonesia. In this review, all reported cases of ZIKV infection in Asia as of September 1, 2016 are summarized and some of the hypotheses that could currently explain the apparently low incidence of Zika cases in Asia are explored.

  17. [Ebola virus disease].

    Science.gov (United States)

    Nazimek, Katarzyna; Bociaga-Jasik, Monika; Bryniarski, Krzysztof; Gałas, Aleksander; Garlicki, Aleksander; Gawda, Anna; Gawlik, Grzegorz; Gil, Krzysztof; Kosz-Vnenchak, Magdalena; Mrozek-Budzyn, Dorota; Olszanecki, Rafał; Piatek, Anna; Zawilińska, Barbara; Marcinkiewicz, Janusz

    2014-01-01

    Ebola is one of the most virulent zoonotic RNA viruses causing in humans haemorrhagic fever with fatality ratio reaching 90%. During the outbreak of 2014 the number of deaths exceeded 8.000. The "imported" cases reported in Western Europe and USA highlighted the extreme risk of Ebola virus spreading outside the African countries. Thus, haemorrhagic fever outbreak is an international epidemiological problem, also due to the lack of approved prevention and therapeutic strategies. The editorial review article briefly summarizes current knowledge on Ebola virus disease epidemiology, etiology, pathogenesis, clinical presentation, diagnosis as well as possible prevention and treatment.

  18. Zika virus in Asia.

    Science.gov (United States)

    Duong, Veasna; Dussart, Philippe; Buchy, Philippe

    2017-01-01

    Zika virus (ZIKV) is an emerging mosquito-borne virus that was first isolated from a sentinel rhesus monkey in the Zika Forest in Uganda in 1947. In Asia, the virus was isolated in Malaysia from Aedes aegypti mosquitoes in 1966, and the first human infections were reported in 1977 in Central Java, Indonesia. In this review, all reported cases of ZIKV infection in Asia as of September 1, 2016 are summarized and some of the hypotheses that could currently explain the apparently low incidence of Zika cases in Asia are explored. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  19. Viruses in reptiles

    Science.gov (United States)

    2011-01-01

    The etiology of reptilian viral diseases can be attributed to a wide range of viruses occurring across different genera and families. Thirty to forty years ago, studies of viruses in reptiles focused mainly on the zoonotic potential of arboviruses in reptiles and much effort went into surveys and challenge trials of a range of reptiles with eastern and western equine encephalitis as well as Japanese encephalitis viruses. In the past decade, outbreaks of infection with West Nile virus in human populations and in farmed alligators in the USA has seen the research emphasis placed on the issue of reptiles, particularly crocodiles and alligators, being susceptible to, and reservoirs for, this serious zoonotic disease. Although there are many recognised reptilian viruses, the evidence for those being primary pathogens is relatively limited. Transmission studies establishing pathogenicity and cofactors are likewise scarce, possibly due to the relatively low commercial importance of reptiles, difficulties with the availability of animals and permits for statistically sound experiments, difficulties with housing of reptiles in an experimental setting or the inability to propagate some viruses in cell culture to sufficient titres for transmission studies. Viruses as causes of direct loss of threatened species, such as the chelonid fibropapilloma associated herpesvirus and ranaviruses in farmed and wild tortoises and turtles, have re-focused attention back to the characterisation of the viruses as well as diagnosis and pathogenesis in the host itself. 1. Introduction 2. Methods for working with reptilian viruses 3. Reptilian viruses described by virus families 3.1. Herpesviridae 3.2. Iridoviridae 3.2.1 Ranavirus 3.2.2 Erythrocytic virus 3.2.3 Iridovirus 3.3. Poxviridae 3.4. Adenoviridae 3.5. Papillomaviridae 3.6. Parvoviridae 3.7. Reoviridae 3.8. Retroviridae and inclusion body disease of Boid snakes 3.9. Arboviruses 3.9.1. Flaviviridae 3.9.2. Togaviridae 3.10. Caliciviridae

  20. Strategy as a Virus

    DEFF Research Database (Denmark)

    Obed Madsen, Søren

    and organizations. In this paper, the virus theory is used to analyze a strategy process in an organization as an example of a technology. It shows how the strategy over time creates a memory loss, where the managers who are exposed to the virus forget their critique of the new strategy concept. The article also...... shows how resistant can be understood as being immune to a virus, since the strategy concepts bears resemblance to a former strategy concept. The article also argues that there should be more focus on the negative impacts of management tool and especially how organizations and managers are dealing...

  1. Significance evaluation in factor graphs.

    Science.gov (United States)

    Madsen, Tobias; Hobolth, Asger; Jensen, Jens Ledet; Pedersen, Jakob Skou

    2017-03-31

    Factor graphs provide a flexible and general framework for specifying probability distributions. They can capture a range of popular and recent models for analysis of both genomics data as well as data from other scientific fields. Owing to the ever larger data sets encountered in genomics and the multiple-testing issues accompanying them, accurate significance evaluation is of great importance. We here address the problem of evaluating statistical significance of observations from factor graph models. Two novel numerical approximations for evaluation of statistical significance are presented. First a method using importance sampling. Second a saddlepoint approximation based method. We develop algorithms to efficiently compute the approximations and compare them to naive sampling and the normal approximation. The individual merits of the methods are analysed both from a theoretical viewpoint and with simulations. A guideline for choosing between the normal approximation, saddle-point approximation and importance sampling is also provided. Finally, the applicability of the methods is demonstrated with examples from cancer genomics, motif-analysis and phylogenetics. The applicability of saddlepoint approximation and importance sampling is demonstrated on known models in the factor graph framework. Using the two methods we can substantially improve computational cost without compromising accuracy. This contribution allows analyses of large datasets in the general factor graph framework.

  2. Plant virus replication and movement

    OpenAIRE

    Heinlein, Manfred

    2015-01-01

    © 2015 Elsevier Inc. Replication and intercellular spread of viruses depend on host mechanisms supporting the formation transport and turnover of functional complexes between viral genomes virus encoded products and cellular factors. To enhance these processes viruses assemble and replicate in membrane associated complexes that may develop into "virus factories" or "viroplasms" in which viral components and host factors required for replication are concentrated. Many plant viruses replicate i...

  3. Virioplankton: Viruses in Aquatic Ecosystems†

    OpenAIRE

    Wommack, K. Eric; Colwell, Rita R.

    2000-01-01

    The discovery that viruses may be the most abundant organisms in natural waters, surpassing the number of bacteria by an order of magnitude, has inspired a resurgence of interest in viruses in the aquatic environment. Surprisingly little was known of the interaction of viruses and their hosts in nature. In the decade since the reports of extraordinarily large virus populations were published, enumeration of viruses in aquatic environments has demonstrated that the virioplankton are dynamic co...

  4. Engineering resistance to virus transmission

    OpenAIRE

    Carr, John Peter; Groen, SC; Wamonje, Francis; Murphy, Alexandra Marie

    2017-01-01

    Engineering plants for resistance to virus transmission by invertebrate vectors has lagged behind other forms of plant protection. Vectors typically transmit more than one virus. Thus, vector resistance could provide a wider range of protection than defenses directed solely against one virus or virus group. We discuss current knowledge of vector-host-virus interactions, the roles of viral gene products in host and vector manipulation, and the effects of semiochemicals on host-vector interact...

  5. Recombinant mumps virus as a cancer therapeutic agent

    Directory of Open Access Journals (Sweden)

    Arun Ammayappan

    2016-01-01

    Full Text Available Mumps virus belongs to the family of Paramyxoviridae and has the potential to be an oncolytic agent. Mumps virus Urabe strain had been tested in the clinical setting as a treatment for human cancer four decades ago in Japan. These clinical studies demonstrated that mumps virus could be a promising cancer therapeutic agent that showed significant antitumor activity against various types of cancers. Since oncolytic virotherapy was not in the limelight until the beginning of the 21st century, the interest to pursue mumps virus for cancer treatment slowly faded away. Recent success stories of oncolytic clinical trials prompted us to resurrect the mumps virus and to explore its potential for cancer treatment. We have obtained the Urabe strain of mumps virus from Osaka University, Japan, which was used in the earlier human clinical trials. In this report we describe the development of a reverse genetics system from a major isolate of this Urabe strain mumps virus stock, and the construction and characterization of several recombinant mumps viruses with additional transgenes. We present initial data demonstrating these recombinant mumps viruses have oncolytic activity against tumor cell lines in vitro and some efficacy in preliminary pilot animal tumor models.

  6. Recombinant mumps virus as a cancer therapeutic agent.

    Science.gov (United States)

    Ammayappan, Arun; Russell, Stephen J; Federspiel, Mark J

    2016-01-01

    Mumps virus belongs to the family of Paramyxoviridae and has the potential to be an oncolytic agent. Mumps virus Urabe strain had been tested in the clinical setting as a treatment for human cancer four decades ago in Japan. These clinical studies demonstrated that mumps virus could be a promising cancer therapeutic agent that showed significant antitumor activity against various types of cancers. Since oncolytic virotherapy was not in the limelight until the beginning of the 21(st) century, the interest to pursue mumps virus for cancer treatment slowly faded away. Recent success stories of oncolytic clinical trials prompted us to resurrect the mumps virus and to explore its potential for cancer treatment. We have obtained the Urabe strain of mumps virus from Osaka University, Japan, which was used in the earlier human clinical trials. In this report we describe the development of a reverse genetics system from a major isolate of this Urabe strain mumps virus stock, and the construction and characterization of several recombinant mumps viruses with additional transgenes. We present initial data demonstrating these recombinant mumps viruses have oncolytic activity against tumor cell lines in vitro and some efficacy in preliminary pilot animal tumor models.

  7. Immunology of Bats and Their Viruses: Challenges and Opportunities

    Directory of Open Access Journals (Sweden)

    Tony Schountz

    2014-12-01

    Full Text Available Bats are reservoir hosts of several high-impact viruses that cause significant human diseases, including Nipah virus, Marburg virus and rabies virus. They also harbor many other viruses that are thought to have caused disease in humans after spillover into intermediate hosts, including SARS and MERS coronaviruses. As is usual with reservoir hosts, these viruses apparently cause little or no pathology in bats. Despite the importance of bats as reservoir hosts of zoonotic and potentially zoonotic agents, virtually nothing is known about the host/virus relationships; principally because few colonies of bats are available for experimental infections, a lack of reagents, methods and expertise for studying bat antiviral responses and immunology, and the difficulty of conducting meaningful field work. These challenges can be addressed, in part, with new technologies that are species-independent that can provide insight into the interactions of bats and viruses, which should clarify how the viruses persist in nature, and what risk factors might facilitate transmission to humans and livestock.

  8. The Regulation of Autophagy by Influenza A Virus

    Directory of Open Access Journals (Sweden)

    Rong Zhang

    2014-01-01

    Full Text Available Influenza A virus is a dreadful pathogen of animals and humans, causing widespread infection and severe morbidity and mortality. It is essential to characterize the influenza A virus-host interaction and develop efficient counter measures against the viral infection. Autophagy is known as a catabolic process for the recycling of the cytoplasmic macromolecules. Recently, it has been shown that autophagy is a critical mechanism underlying the interaction between influenza A virus and its host. Autophagy can be induced by the infection with influenza A virus, which is considered as a necessary process for the viral proliferation, including the accumulation of viral elements during the replication of influenza A virus. On the other hand, influenza A virus can inhibit the autophagic formation via interaction with the autophagy-related genes (Atg and signaling pathways. In addition, autophagy is involved in the influenza virus-regulated cell deaths, leading to significant changes in host apoptosis. Interestingly, the high pathogenic strains of influenza A virus, such as H5N1, stimulate autophagic cell death and appear to interplay with the autophagy in distinct ways as compared with low pathogenic strains. This review discusses the regulation of autophagy, an influenza A virus driven process.

  9. Human muscle satellite cells as targets of Chikungunya virus infection.

    Directory of Open Access Journals (Sweden)

    Simona Ozden

    Full Text Available BACKGROUND: Chikungunya (CHIK virus is a mosquito-transmitted alphavirus that causes in humans an acute infection characterised by fever, polyarthralgia, head-ache, and myalgia. Since 2005, the emergence of CHIK virus was associated with an unprecedented magnitude outbreak of CHIK disease in the Indian Ocean. Clinically, this outbreak was characterized by invalidating poly-arthralgia, with myalgia being reported in 97.7% of cases. Since the cellular targets of CHIK virus in humans are unknown, we studied the pathogenic events and targets of CHIK infection in skeletal muscle. METHODOLOGY/PRINCIPAL FINDINGS: Immunohistology on muscle biopsies from two CHIK virus-infected patients with myositic syndrome showed that viral antigens were found exclusively inside skeletal muscle progenitor cells (designed as satelllite cells, and not in muscle fibers. To evaluate the ability of CHIK virus to replicate in human satellite cells, we assessed virus infection on primary human muscle cells; viral growth was observed in CHIK virus-infected satellite cells with a cytopathic effect, whereas myotubes were essentially refractory to infection. CONCLUSIONS/SIGNIFICANCE: This report provides new insights into CHIK virus pathogenesis, since it is the first to identify a cellular target of CHIK virus in humans and to report a selective infection of muscle satellite cells by a viral agent in humans.

  10. Aptamer-facilitated Protection of Oncolytic Virus from Neutralizing Antibodies.

    Science.gov (United States)

    Muharemagic, Darija; Zamay, Anna; Ghobadloo, Shahrokh M; Evgin, Laura; Savitskaya, Anna; Bell, John C; Berezovski, Maxim V

    2014-06-03

    Oncolytic viruses promise to significantly improve current cancer treatments through their tumor-selective replication and multimodal attack against cancer cells. However, one of the biggest setbacks for oncolytic virus therapy is the intravenous delivery of the virus, as it can be cleared from the bloodstream by neutralizing antibodies before it reaches the tumor cells. We have selected DNA aptamers against an oncolytic virus, vesicular stomatitis virus, using a competitive binding approach, as well as against the antigen binding fragment (Fab) of antivesicular stomatitis virus polyclonal antibodies, in order to shield the virus from nAbs and enhance its in vivo survival. We used flow cytometry to identify these aptamers and evaluated their efficiency to shield vesicular stomatitis virus in a cell-based plaque forming assay. These oligonucleotides were then modified to obtain multivalent binders, which led to a decrease of viral aggregation, an increase in its infectivity and an increase in its stability in serum. The aptamers were also incubated in nondiluted serum, showing their effectiveness under conditions mimicking those in vivo. With this approach, we were able to increase viral infectivity by more than 70% in the presence of neutralizing antibodies. Thus, this method has the potential to enhance the delivery of vesicular stomatitis virus through the bloodstream without compromising the patient's immune system.

  11. Comparative Study of Non-Enveloped Icosahedral Viruses Size.

    Directory of Open Access Journals (Sweden)

    Nikolai Nikitin

    Full Text Available Now, as before, transmission electron microscopy (TEM is a widely used technique for the determination of virions size. In some studies, dynamic light scattering (DLS has also been applied for this purpose. Data obtained by different authors and using different methods could vary significantly. The process of TEM sample preparation involves drying on the substrate, which can cause virions to undergo morphology changes. Therefore, other techniques should be used for measurements of virions size in liquid, (i.e. under conditions closer to native. DLS and nanoparticle tracking analysis (NTA provide supplementary data about the virions hydrodynamic diameter and aggregation state in liquid. In contrast to DLS, NTA data have a higher resolution and also are less sensitive to minor admixtures. In the present work, the size of non-enveloped icosahedral viruses of different nature was analyzed by TEM, DLS and NTA: the viruses used were the encephalomyocarditis virus (animal virus, and cauliflower mosaic virus, brome mosaic virus and bean mild mosaic virus (plant viruses. The same, freshly purified, samples of each virus were used for analysis using the different techniques. The results were compared with earlier published data and description databases. DLS data about the hydrodynamic diameter of bean mild mosaic virus, and NTA data for all examined viruses, were obtained for the first time. For all virus samples, the values of size obtained by TEM were less than virions sizes determined by DLS and NTA. The contribution of the electrical double layer (EDL in virions hydrodynamic diameter was evaluated. DLS and NTA data adjusted for EDL thickness were in better agreement with TEM results.

  12. Sequence and phylogenetic analysis of chicken anaemia virus obtained from backyard and commercial chickens in Nigeria : research communication

    Directory of Open Access Journals (Sweden)

    D.O. Oluwayelu

    2008-09-01

    Full Text Available This work reports the first molecular analysis study of chicken anaemia virus (CAV in backyard chickens in Africa using molecular cloning and sequence analysis to characterize CAV strains obtained from commercial chickens and Nigerian backyard chickens. Partial VP1 gene sequences were determined for three CAVs from commercial chickens and for six CAV variants present in samples from a backyard chicken. Multiple alignment analysis revealed that the 6 % and 4 % nucleotide diversity obtained respectively for the commercial and backyard chicken strains translated to only 2 % amino acid diversity for each breed. Overall, the amino acid composition of Nigerian CAVs was found to be highly conserved. Since the partial VP1 gene sequence of two backyard chicken cloned CAV strains (NGR/Cl-8 and NGR/Cl-9 were almost identical and evolutionarily closely related to the commercial chicken strains NGR-1, and NGR-4 and NGR-5, respectively, we concluded that CAV infections had crossed the farm boundary.

  13. Rota virus infections: prevalence, diagnosis and prevention

    National Research Council Canada - National Science Library

    Vidya, Padmanabhan; Ponnambalam, Arun; Gunasekeran, Palani; Arunagiri, Kavitha; Sambasivam, Mohana; Krishnasami, Kaveri

    2015-01-01

    ...: Molecular typing methods for viruses should aim to provide clinically and biologically useful information about field viruses, particularly with regard to virulence, viral epidemiology, and virus...

  14. Lassa Virus Reverse Genetics.

    Science.gov (United States)

    Martínez-Sobrido, Luis; Paessler, Slobodan; de la Torre, Juan Carlos

    2017-01-01

    The Old World (OW) arenavirus Lassa (LASV ) is estimated to infect several hundred thousand people yearly in West Africa, resulting in high numbers of Lassa fever (LF), a viral hemorrhagic fever (HF) disease associated with high morbidity and mortality. To date, no licensed vaccines are available to LASV infections, and anti-LASV drug therapy is limited to an off-label use of ribavirin (Rib) that is only partially effective. The development of reverse genetics has provided investigators with a novel and powerful approach for the investigation of the molecular, cell biology, and pathogenesis of LASV. The use of cell-based LASV minigenome (MG) systems has allowed examining the cis- and trans-acting factors involved in genome replication and gene transcription and the identification of novel drugable LASV targets. Likewise, it is now feasible to rescue infectious recombinant (r)LASV entirely from cloned cDNAs containing predetermined mutations in their genomes to investigate virus-host interactions and mechanisms of pathogenesis, as well as to facilitate screens to identify antiviral drugs against LASV and the implementation of novel strategies to develop live-attenuated vaccines (LAV). In this chapter we will summarize the state-of-the-art experimental procedures for implementation of LASV reverse genetics. In addition, we will briefly discuss some significant translational research developments that have been made possible upon the development of LASV reverse genetics.

  15. Recombinant measles viruses expressing respiratory syncytial virus proteins induced virus-specific CTL responses in cotton rats.

    Science.gov (United States)

    Yamaji, Yoshiaki; Nakayama, Tetsuo

    2014-07-31

    Respiratory syncytial virus (RSV) is a common cause of serious lower respiratory tract illnesses in infants. Natural infections with RSV provide limited protection against reinfection because of inefficient immunological responses that do not induce long-term memory. RSV natural infection has been shown to induce unbalanced immune response. The effective clearance of RSV is known to require the induction of a balanced Th1/Th2 immune response, which involves the induction of cytotoxic T lymphocytes (CTL). In our previous study, recombinant AIK-C measles vaccine strains MVAIK/RSV/F and MVAIK/RSV/G were developed, which expressed the RSV fusion (F) protein or glycoprotein (G). These recombinant viruses elicited antibody responses against RSV in cotton rats, and no infectious virus was recovered, but small amounts of infiltration of inflammatory cells were observed in the lungs following RSV challenge. In the present study, recombinant AIK-C measles vaccine strains MVAIK/RSV/M2-1 and MVAIK/RSV/NP were developed, expressing RSV M2-1 or Nucleoprotein (NP), respectively. These viruses exhibited temperature-sensitivity (ts), which was derived from AIK-C, and expressed respective RSV antigens. The intramuscular inoculation of cotton rats with the recombinant measles virus led to the induction of CD8(+) IFN-γ(+) cells. No infectious virus was recovered from a lung homogenate following the challenge. A Histological examination of the lungs revealed a significant reduction in inflammatory reactions without alveolar damage. These results support the recombinant measles viruses being effective vaccine candidates against RSV that induce RSV-specific CTL responses with or without the development of an antibody response. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Clinical significance of neonatal menstruation.

    Science.gov (United States)

    Brosens, Ivo; Benagiano, Giuseppe

    2016-01-01

    Past studies have clearly shown the existence of a spectrum of endometrial progesterone responses in neonatal endometrium, varying from proliferation to full decidualization with menstrual-like shedding. The bleedings represent, similar to what occurs in adult menstruation, a progesterone withdrawal bleeding. Today, the bleeding is completely neglected and considered an uneventful episode of no clinical significance. Yet clinical studies have linked the risk of bleeding to a series of events indicating fetal distress. The potential link between the progesterone response and major adolescent disorders requires to be investigated by prospective studies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. Moral significance of phenomenal consciousness.

    Science.gov (United States)

    Levy, Neil; Savulescu, Julian

    2009-01-01

    Recent work in neuroimaging suggests that some patients diagnosed as being in the persistent vegetative state are actually conscious. In this paper, we critically examine this new evidence. We argue that though it remains open to alternative interpretations, it strongly suggests the presence of consciousness in some patients. However, we argue that its ethical significance is less than many people seem to think. There are several different kinds of consciousness, and though all kinds of consciousness have some ethical significance, different kinds underwrite different kinds of moral value. Demonstrating that patients have phenomenal consciousness--conscious states with some kind of qualitative feel to them--shows that they are moral patients, whose welfare must be taken into consideration. But only if they are subjects of a sophisticated kind of access consciousness--where access consciousness entails global availability of information to cognitive systems--are they persons, in the technical sense of the word employed by philosophers. In this sense, being a person is having the full moral status of ordinary human beings. We call for further research which might settle whether patients who manifest signs of consciousness possess the sophisticated kind of access consciousness required for personhood.

  18. Significances of Multimedia Technologies Training

    Science.gov (United States)

    Zhang, Fulei

    The use of multimedia technologies in education has enabled teachers to simulate final outcomes and assist s-tudents in applying knowledge learned from textbooks, thereby compensating for the deficiency of traditional teach- ing methods. It is important to examine how effective these technologies are in practical use. This study developed online learning-teaching resource platforms using Flash multimedia, providing interactive and integrated features in an easy-to-use user interface, in order to discuss Computer-Aided Drawing (CAD). The study utilized a teaching experiment with a non-equivalent pretest-posttest control group design to test and discuss students' professional cognition, operating skill cognition, and level of learning satisfaction during the learning process. No significant differences emerged between the groups in regards to professional cognition or operation skills cognition. However, a significant difference in learning satisfaction was noted, indicating that the coursework with multimedia Flash produced greater satisfaction than with traditional learning methods. Results are explained in detail and recommendations for further research provided.

  19. Monoclonal gammopathies of renal significance.

    Science.gov (United States)

    Caravaca-Fontán, Fernando; Gutiérrez, Eduardo; Delgado Lillo, Ramón; Praga, Manuel

    The term monoclonal gammopathy of renal significance (MGRS) comprises a group of diseases pathogenetically characterised by proliferation of a B-cell or plasma cell clone that synthesises and secretes a monoclonal immunoglobulin or its components (light and/or heavy chains), that may deposit and cause glomerular, tubular, interstitial and/or vascular damage. The importance of differentiating the term MGRS from other monoclonal gammopathies lies in the fact that diagnostic and therapeutic procedures aimed at controlling monoclonal protein synthesis and secretion can be indicated, irrespective of the classic criteria based on malignant tumour expansion. Renal pathology associated with MGRS is highly heterogeneous, and therefore renal biopsy should be considered a key diagnostic tool. A precise diagnostic approach, however, must also identify the monoclonal protein in plasma and/or in urine, together with a complete haematological study in order to determine the nature and extension of cell clones. Recent advances in the understanding of these entities have resulted in significant improvements in clinical course and survival in several forms of MGRS, although more studies and clinical experience are needed in order to delineate more effective therapeutic strategies. In this review, we summarise the main clinical and pathological features of MGRS, highlighting the most appropriate diagnostic approach and current therapeutic options. Copyright © 2017 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  20. Development of high-yield influenza B virus vaccine viruses.

    Science.gov (United States)

    Ping, Jihui; Lopes, Tiago J S; Neumann, Gabriele; Kawaoka, Yoshihiro

    2016-12-20

    The burden of human infections with influenza A and B viruses is substantial, and the impact of influenza B virus infections can exceed that of influenza A virus infections in some seasons. Over the past few decades, viruses of two influenza B virus lineages (Victoria and Yamagata) have circulated in humans, and both lineages are now represented in influenza vaccines, as recommended by the World Health Organization. Influenza B virus vaccines for humans have been available for more than half a century, yet no systematic efforts have been undertaken to develop high-yield candidates. Therefore, we screened virus libraries possessing random mutations in the six "internal" influenza B viral RNA segments [i.e., those not encoding the major viral antigens, hemagglutinin (HA) and neuraminidase NA)] for mutants that confer efficient replication. Candidate viruses that supported high yield in cell culture were tested with the HA and NA genes of eight different viruses of the Victoria and Yamagata lineages. We identified combinations of mutations that increased the titers of candidate vaccine viruses in mammalian cells used for human influenza vaccine virus propagation and in embryonated chicken eggs, the most common propagation system for influenza viruses. These influenza B virus vaccine backbones can be used for improved vaccine virus production.

  1. Molecular Mechanism for LAMP1 Recognition by Lassa Virus.

    Science.gov (United States)

    Cohen-Dvashi, Hadas; Cohen, Nadav; Israeli, Hadar; Diskin, Ron

    2015-08-01

    Lassa virus is a notorious human pathogen that infects many thousands of people each year in West Africa, causing severe viral hemorrhagic fevers and significant mortality. The surface glycoprotein of Lassa virus mediates receptor recognition through its GP1 subunit. Here we report the crystal structure of GP1 from Lassa virus, which is the first representative GP1 structure for Old World arenaviruses. We identify a unique triad of histidines that forms a binding site for LAMP1, a known lysosomal protein recently discovered to be a critical receptor for internalized Lassa virus at acidic pH. We demonstrate that mutation of this histidine triad, which is highly conserved among Old World arenaviruses, impairs LAMP1 recognition. Our biochemical and structural data further suggest that GP1 from Lassa virus may undergo irreversible conformational changes that could serve as an immunological decoy mechanism. Together with a variable region that we identify on the surface of GP1, those could be two distinct mechanisms that Lassa virus utilizes to avoid antibody-based immune response. Structural data at atomic resolution for viral proteins is key for understanding their function at the molecular level and can facilitate novel avenues for combating viral infections. Here we used X-ray protein crystallography to decipher the crystal structure of the receptor-binding domain (GP1) from Lassa virus. This is a pathogenic virus that causes significant illness and mortality in West Africa. This structure reveals the overall architecture of GP1 domains from the group of viruses known as the Old World arenaviruses. Using this structural information, we elucidated the mechanisms for pH switch and binding of Lassa virus to LAMP1, a recently identified host receptor that is critical for successful infection. Lastly, our structural analysis suggests two novel immune evasion mechanisms that Lassa virus may utilize to escape antibody-based immune response. Copyright © 2015, American

  2. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Connection Home Clinical Guidance & Publications Practice Management Education & Events Advocacy For Patients About ACOG Zika Virus and ... Practice Patient Safety & Quality Payment Reform (MACRA) Education & Events Annual Meeting CME Overview CREOG Meetings Calendar Congressional ...

  3. West Nile Virus

    Science.gov (United States)

    ... of Whether Lower Respiratory Tract Infections Improve with Antibacterial Treatment , February 13, 2018 NIH Scientists Adapt New ... ecological patterns in the United States, and insecticide resistance. Read more about West Nile virus biology, genetics ...

  4. Hepatitis B virus (image)

    Science.gov (United States)

    Hepatitis B is also known as serum hepatitis and is spread through blood and sexual contact. It is ... population. This photograph is an electronmicroscopic image of hepatitis B virus particles. (Image courtesy of the Centers for ...

  5. The virus of management

    DEFF Research Database (Denmark)

    Kjær, Peter; Frankel, Christian

    2003-01-01

    The virus metaphor may be used in studies of management knowledge not only as a way ofdescribing diffusion processes but also as a way of thinking about viral elements of knowledgeproduction. In the present article, organizational viruses are viewed as ensembles of basicdistinctions...... that are constitutive of concrete bodies of knowledge and which form mutable enginesof organizational self-descriptions. Organizational viruses, we contend, are both characterized bystability in terms of their basic productive configuration, while at the same time allowing for a highdegree of variation in terms...... of concrete management knowledge and practice. The article isstructured as follows. After the introduction, we first develop the notion of organizational virus asinto an analytical approach. Second, we discern in the work of Frederick Taylor on scientificmanagement and Max Weber on bureaucracy, two quite...

  6. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Career Connection Home Clinical Guidance & Publications Practice Management Education & Events Advocacy For Patients About ACOG Zika Virus ... and Pregnancy Page Navigation ▼ ACOG Pregnancy Book Patient Education FAQs Patient Education Pamphlets - Spanish Share: PEV002, September ...

  7. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Departments Donate Shop Career Connection Home Clinical Guidance & Publications Practice Management Education & Events Advocacy For Patients About ... pregnant. Related: Zika Virus and Pregnancy ... Committee Opinions Practice Bulletins Patient Education Green Journal ...

  8. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Pregnancy Book Patient Education FAQs Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy ... Council on Patient Safety For Patients Patient FAQs Spanish Pamphlets Teen Health About ACOG About Us Leadership & ...

  9. Zika Virus and Pregnancy

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    Full Text Available ... Zika Virus and Pregnancy Page Navigation ▼ ACOG Pregnancy Book Patient Education FAQs Patient Education Pamphlets - Spanish Share: ... Us Contact Us Copyright Information Privacy Statement RSS Advertising Opportunities Careers at ACOG Sitemap Website Feedback American ...

  10. Influenza (Flu) Viruses

    Science.gov (United States)

    ... Virus Testing Clinical Signs & Symptoms of Influenza Symptoms & Laboratory Diagnosis Information for Clinicians on Rapid Diagnostic Testing for ... Help: How do I view different file formats (PDF, DOC, PPT, MPEG) on this site? Adobe PDF ...

  11. Zika Virus and Pregnancy

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    Full Text Available ... Departments Donate Shop Career Connection Home Clinical Guidance & Publications Practice Management Education & Events Advocacy For Patients About ... pregnant. Related: Zika Virus and Pregnancy Infographic Resources & Publications Committee Opinions Practice Bulletins Patient Education Green Journal ...

  12. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... My ACOG Join Pay Dues Follow us: Women's Health Care Physicians Contact Us My ACOG ACOG Departments Donate Shop Career Connection Home Clinical Guidance & Publications Practice Management Education & Events Advocacy For Patients About ACOG Zika Virus ...

  13. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Shop Career Connection Home Resources & Publications Practice Management Education & Events Advocacy For Patients About ACOG Zika Virus ... and Pregnancy Page Navigation ▼ ACOG Pregnancy Book Patient Education FAQs Patient Education Pamphlets - Spanish Share: PEV002, September ...

  14. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Zika Virus and Pregnancy Page Navigation ▼ ACOG Pregnancy Book Patient Education FAQs Patient Education Pamphlets - Spanish ACOG Pregnancy Book Patient Ed. ACOG Pregnancy Book Patient Ed. 2 ...

  15. Ebola Virus Disease

    Science.gov (United States)

    ... patients at home. Reducing the risk of possible sexual transmission, based on further analysis of ongoing research and consideration by the WHO Advisory Group on the Ebola Virus Disease Response, WHO recommends that male survivors of Ebola ...

  16. Respiratory Syncytial Virus

    Science.gov (United States)

    ... When to Call the Doctor en español Virus respiratorio sincitial About RSV Respiratory syncytial (sin-SISH-ul) ... diseases that affect the lungs, heart, or immune system , RSV infections can lead to other more serious ...

  17. Ebola Virus Disease

    National Research Council Canada - National Science Library

    PV Bhargavan; PV Shiji; Jare Jagannath Udhavrao; Nagaraj Desai

    2015-01-01

    Ebola virus is named after the river in the former Zaire where a haemorrhagic fever initially identified in 1976 involved human to human transmission, as well as spread by contaminated injection equipments...

  18. Zika Virus and Pregnancy

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    Full Text Available ... Donate Shop Career Connection Home Resources & Publications Practice Management Education & Events Advocacy For Patients About ACOG Zika Virus and ... Bulletins Patient Education Green Journal Clinical Updates ... Annual Meeting CME Overview CREOG Meetings Calendar Congressional ...

  19. Zika Virus and Pregnancy

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    Full Text Available ... Donate Shop Career Connection Home Resources & Publications Practice Management Education & Events Advocacy For Patients About ACOG Zika Virus ... Infographic Resources & Publications Committee Opinions Practice ... Coding Health Info Technology Professional Liability Managing Your ...

  20. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... are pregnant. Related: Zika Virus and Pregnancy Infographic Resources & Publications Committee Opinions Practice Bulletins Patient Education Green Journal Clinical Updates Practice Management Coding Health Info Technology Professional Liability Managing Your ...

  1. Virus-neutralizing antibody response of mice to consecutive infection with human and avian influenza A viruses.

    Science.gov (United States)

    Janulíková, J; Stropkovská, A; Bobišová, Z; Košík, I; Mucha, V; Kostolanský, F; Varečková, E

    2015-06-01

    In this work we simulated in a mouse model a naturally occurring situation of humans, who overcame an infection with epidemic strains of influenza A, and were subsequently exposed to avian influenza A viruses (IAV). The antibody response to avian IAV in mice previously infected with human IAV was analyzed. We used two avian IAV (A/Duck/Czechoslovakia/1956 (H4N6) and the attenuated virus rA/Viet Nam/1203-2004 (H5N1)) as well as two human IAV isolates (virus A/Mississippi/1/1985 (H3N2) of medium virulence and A/Puerto Rico/8/1934 (H1N1) of high virulence). Two repeated doses of IAV of H4 or of H5 virus elicited virus-specific neutralizing antibodies in mice. Exposure of animals previously infected with human IAV (of H3 or H1 subtype) to IAV of H4 subtype led to the production of antibodies neutralizing H4 virus in a level comparable with the level of antibodies against the human IAV used for primary infection. In contrast, no measurable levels of virus-neutralizing (VN) antibodies specific to H5 virus were detected in mice infected with H5 virus following a previous infection with human IAV. In both cases the secondary infection with avian IAV led to a significant increase of the titer of VN antibodies specific to the corresponding human virus used for primary infection. Moreover, cross-reactive HA2-specific antibodies were also induced by sequential infection. By virtue of these results we suggest that the differences in the ability of avian IAV to induce specific antibodies inhibiting virus replication after previous infection of mice with human viruses can have an impact on the interspecies transmission and spread of avian IAV in the human population.

  2. Cloned defective interfering influenza virus protects ferrets from pandemic 2009 influenza A virus and allows protective immunity to be established.

    Directory of Open Access Journals (Sweden)

    Nigel J Dimmock

    Full Text Available Influenza A viruses are a major cause of morbidity and mortality in the human population, causing epidemics in the winter, and occasional worldwide pandemics. In addition there are periodic outbreaks in domestic poultry, horses, pigs, dogs, and cats. Infections of domestic birds can be fatal for the birds and their human contacts. Control in man operates through vaccines and antivirals, but both have their limitations. In the search for an alternative treatment we have focussed on defective interfering (DI influenza A virus. Such a DI virus is superficially indistinguishable from a normal virus but has a large deletion in one of the eight RNAs that make up the viral genome. Antiviral activity resides in the deleted RNA. We have cloned one such highly active DI RNA derived from segment 1 (244 DI virus and shown earlier that intranasal administration protects mice from lethal disease caused by a number of different influenza A viruses. A more cogent model of human influenza is the ferret. Here we found that intranasal treatment with a single dose of 2 or 0.2 µg 244 RNA delivered as A/PR/8/34 virus particles protected ferrets from disease caused by pandemic virus A/California/04/09 (A/Cal; H1N1. Specifically, 244 DI virus significantly reduced fever, weight loss, respiratory symptoms, and infectious load. 244 DI RNA, the active principle, was amplified in nasal washes following infection with A/Cal, consistent with its amelioration of clinical disease. Animals that were treated with 244 DI RNA cleared infectious and DI viruses without delay. Despite the attenuation of infection and disease by DI virus, ferrets formed high levels of A/Cal-specific serum haemagglutination-inhibiting antibodies and were solidly immune to rechallenge with A/Cal. Together with earlier data from mouse studies, we conclude that 244 DI virus is a highly effective antiviral with activity potentially against all influenza A subtypes.

  3. Neonatal Herpes Simplex Virus Infection.

    Science.gov (United States)

    James, Scott H; Kimberlin, David W

    2015-09-01

    Herpes simplex virus (HSV) 1 and HSV-2 infections are highly prevalent worldwide and are characterized by establishing lifelong infection with periods of latency interspersed with periodic episodes of reactivation. Acquisition of HSV by an infant during the peripartum or postpartum period results in neonatal HSV disease, a rare but significant infection that can be associated with severe morbidity and mortality, especially if there is dissemination or central nervous system involvement. Diagnostic and therapeutic advances have led to improvements in mortality and, to a lesser extent, neurodevelopmental outcomes, but room exists for further improvement. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Respiratory Syncytial Virus (RSV)

    Centers for Disease Control (CDC) Podcasts

    2013-02-04

    Respiratory Syncytial Virus, or RSV, causes cold-like symptoms but can be serious for infants and older adults. In this podcast, CDC’s Dr. Eileen Schneider discusses this common virus and offers tips to prevent its spread.  Created: 2/4/2013 by National Center for Immunization and Respiratory Diseases (NCIRD), Division of Viral Diseases (DVD).   Date Released: 2/13/2013.

  5. Zika Virus Outside Africa

    OpenAIRE

    Hayes, Edward B.

    2009-01-01

    Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic ...

  6. Hepatitis E Virus

    Directory of Open Access Journals (Sweden)

    Christina Levick

    2014-05-01

    Full Text Available Hepatitis E virus (HEV is the most common cause of acute viral hepatitis in the developing world. It is a waterborne virus that can cause epidemics in the face of overcrowding and poor sanitation. Although the hepatitis illness is usually self-limiting, it has a high mortality in pregnant women and can become a chronic infection in the immunosuppressed. Treatment is mostly supportive and prevention is by good water hygiene.

  7. Clinical significance of precipitous labor.

    Science.gov (United States)

    Suzuki, Shunji

    2015-03-01

    Precipitous labor is defined as expulsion of the fetus within less than 3 hours of commencement of regular contractions. We retrospectively examined our cases of precipitous labor to identify the clinical significance and perinatal outcomes following precipitous labor in singleton vertex deliveries. A retrospective population-based study was conducted comparing women with singleton precipitous labor and those with labor of normal duration. We examined the clinical characteristics and outcomes by comparing patients with precipitous labor and those with labor of normal duration in 0 and two-parous singleton pregnant women. Using a multivariate analysis, precipitous labor in nulliparous women was independently associated with teenagers (adjusted OR: 1.71, 95% CI: 0.99 - 2.95, P = 0.049), preterm delivery (adjusted OR: 1.77, 95% CI: 1.16 - 2.70, P precipitous labor was associated with hypertensive disorders in singleton vertex deliveries, it was not associated with maternal or neonatal outcomes.

  8. The significance of small streams

    Science.gov (United States)

    Wohl, Ellen

    2017-09-01

    Headwaters, defined here as first- and secondorder streams, make up 70%‒80% of the total channel length of river networks. These small streams exert a critical influence on downstream portions of the river network by: retaining or transmitting sediment and nutrients; providing habitat and refuge for diverse aquatic and riparian organisms; creating migration corridors; and governing connectivity at the watershed-scale. The upstream-most extent of the channel network and the longitudinal continuity and lateral extent of headwaters can be difficult to delineate, however, and people are less likely to recognize the importance of headwaters relative to other portions of a river network. Consequently, headwaters commonly lack the legal protections accorded to other portions of a river network and are more likely to be significantly altered or completely obliterated by land use.

  9. The significance of constitutional values

    Directory of Open Access Journals (Sweden)

    HN Nisihara

    2001-12-01

    Full Text Available This article addresses the question of the meaning and legal significance of constitutional values in contemporary times. The article attends also to related questions namely, what constitute “constitutional values” and what are the limitations of the meaning afforded to this notion. Attention is paid in the particular, to freedom, equality and democracy as value-neutral criteria of fairness and government neutrality with reference to the South African and German contexts as well as to value-neutrality as a culturally conditioned value. The author concludes with a cosmopolitan view of freedom and the right to peace with reference to the constitutional texts of Japan and the United States.

  10. The energetic significance of cooking.

    Science.gov (United States)

    Carmody, Rachel N; Wrangham, Richard W

    2009-10-01

    While cooking has long been argued to improve the diet, the nature of the improvement has not been well defined. As a result, the evolutionary significance of cooking has variously been proposed as being substantial or relatively trivial. In this paper, we evaluate the hypothesis that an important and consistent effect of cooking food is a rise in its net energy value. The pathways by which cooking influences net energy value differ for starch, protein, and lipid, and we therefore consider plant and animal foods separately. Evidence of compromised physiological performance among individuals on raw diets supports the hypothesis that cooked diets tend to provide energy. Mechanisms contributing to energy being gained from cooking include increased digestibility of starch and protein, reduced costs of digestion for cooked versus raw meat, and reduced energetic costs of detoxification and defence against pathogens. If cooking consistently improves the energetic value of foods through such mechanisms, its evolutionary impact depends partly on the relative energetic benefits of non-thermal processing methods used prior to cooking. We suggest that if non-thermal processing methods such as pounding were used by Lower Palaeolithic Homo, they likely provided an important increase in energy gain over unprocessed raw diets. However, cooking has critical effects not easily achievable by non-thermal processing, including the relatively complete gelatinisation of starch, efficient denaturing of proteins, and killing of food borne pathogens. This means that however sophisticated the non-thermal processing methods were, cooking would have conferred incremental energetic benefits. While much remains to be discovered, we conclude that the adoption of cooking would have led to an important rise in energy availability. For this reason, we predict that cooking had substantial evolutionary significance.

  11. The Genomes of Sheeppox and Goatpox Viruses

    Science.gov (United States)

    Tulman, E. R.; Afonso, C. L.; Lu, Z.; Zsak, L.; Sur, J.-H.; Sandybaev, N. T.; Kerembekova, U. Z.; Zaitsev, V. L.; Kutish, G. F.; Rock, D. L.

    2002-01-01

    Sheeppox virus (SPPV) and goatpox virus (GTPV), members of the Capripoxvirus genus of the Poxviridae, are etiologic agents of important diseases of sheep and goats in northern and central Africa, southwest and central Asia, and the Indian subcontinent. Here we report the genomic sequence and comparative analysis of five SPPV and GTPV isolates, including three pathogenic field isolates and two attenuated vaccine viruses. SPPV and GTPV genomes are approximately 150 kbp and are strikingly similar to each other, exhibiting 96% nucleotide identity over their entire length. Wild-type genomes share at least 147 putative genes, including conserved poxvirus replicative and structural genes and genes likely involved in virulence and host range. SPPV and GTPV genomes are very similar to that of lumpy skin disease virus (LSDV), sharing 97% nucleotide identity. All SPPV and GTPV genes are present in LSDV. Notably in both SPPV and GTPV genomes, nine LSDV genes with likely virulence and host range functions are disrupted, including a gene unique to LSDV (LSDV132) and genes similar to those coding for interleukin-1 receptor, myxoma virus M003.2 and M004.1 genes (two copies each), and vaccinia virus F11L, N2L, and K7L genes. The absence of these genes in SPPV and GTPV suggests a significant role for them in the bovine host range. SPPV and GTPV genomes contain specific nucleotide differences, suggesting they are phylogenetically distinct. Relatively few genomic changes in SPPV and GTPV vaccine viruses account for viral attenuation, because they contain 71 and 7 genomic changes compared to their respective field strains. Notable genetic changes include mutation or disruption of genes with predicted functions involving virulence and host range, including two ankyrin repeat proteins in SPPV and three kelch-like proteins in GTPV. These comparative genomic data indicate the close genetic relationship among capripoxviruses, and they suggest that SPPV and GTPV are distinct and likely

  12. Chimeric Hemagglutinin Constructs Induce Broad Protection against Influenza B Virus Challenge in the Mouse Model.

    Science.gov (United States)

    Ermler, Megan E; Kirkpatrick, Ericka; Sun, Weina; Hai, Rong; Amanat, Fatima; Chromikova, Veronika; Palese, Peter; Krammer, Florian

    2017-06-15

    Seasonal influenza virus epidemics represent a significant public health burden. Approximately 25% of all influenza virus infections are caused by type B viruses, and these infections can be severe, especially in children. Current influenza virus vaccines are an effective prophylaxis against infection but are impacted by rapid antigenic drift, which can lead to mismatches between vaccine strains and circulating strains. Here, we describe a broadly protective vaccine candidate based on chimeric hemagglutinins, consisting of globular head domains from exotic influenza A viruses and stalk domains from influenza B viruses. Sequential vaccination with these constructs in mice leads to the induction of broadly reactive antibodies that bind to the conserved stalk domain of influenza B virus hemagglutinin. Vaccinated mice are protected from lethal challenge with diverse influenza B viruses. Results from serum transfer experiments and antibody-dependent cell-mediated cytotoxicity (ADCC) assays indicate that this protection is antibody mediated and based on Fc effector functions. The present data suggest that chimeric hemagglutinin-based vaccination is a viable strategy to broadly protect against influenza B virus infection.IMPORTANCE While current influenza virus vaccines are effective, they are affected by mismatches between vaccine strains and circulating strains. Furthermore, the antiviral drug oseltamivir is less effective for treating influenza B virus infections than for treating influenza A virus infections. A vaccine that induces broad and long-lasting protection against influenza B viruses is therefore urgently needed. Copyright © 2017 American Society for Microbiology.

  13. [Study in the killing effect of Myxoma virus to C6 glioma cell in vitro].

    Science.gov (United States)

    Zang, Meng; Zhang, Qiu-Sheng; Liang, Shi-Jie; Ji, Tao; Lin, Heng-Zhou; Li, Wei-Ping

    2012-02-01

    To evaluate the susceptibility of C6 glioma cells to Myxoma virus and the killing effect of Myxoma virus to the C6 glioma cells in vitro. C6 glioma cells were infected with myxoma virus, used death virus as the negative control, 5-FU as the positive control, DEMD as blank control. The number of living cells were counted every 24 h, and Western-Blot method, inverted microscope and MTT assay were applicated to observe the cell morphology and survival rate in each group. The cell number were decreased rapidly in virus effected group and 5-FU group, with significant differences to the negative and blank control groups. And cells in virus effected group appeared cytopathic effect. C6 glioma cells were susceptible to myxoma virus and myxoma virus had killing effect to C6 glioma cells in vitro.

  14. Virus-derived transgenes expressing hairpin RNA give immunity to Tobacco mosaic virus and Cucumber mosaic virus

    Directory of Open Access Journals (Sweden)

    Liu Yong

    2011-01-01

    Full Text Available Abstract Background An effective method for obtaining resistant transgenic plants is to induce RNA silencing by expressing virus-derived dsRNA in plants and this method has been successfully implemented for the generation of different plant lines resistant to many plant viruses. Results Inverted repeats of the partial Tobacco mosaic virus (TMV movement protein (MP gene and the partial Cucumber mosaic virus (CMV replication protein (Rep gene were introduced into the plant expression vector and the recombinant plasmids were transformed into Agrobacterium tumefaciens. Agrobacterium-mediated transformation was carried out and three transgenic tobacco lines (MP16-17-3, MP16-17-29 and MP16-17-58 immune to TMV infection and three transgenic tobacco lines (Rep15-1-1, Rep15-1-7 and Rep15-1-32 immune to CMV infection were obtained. Virus inoculation assays showed that the resistance of these transgenic plants could inherit and keep stable in T4 progeny. The low temperature (15℃ did not influence the resistance of transgenic plants. There was no significant correlation between the resistance and the copy number of the transgene. CMV infection could not break the resistance to TMV in the transgenic tobacco plants expressing TMV hairpin MP RNA. Conclusions We have demonstrated that transgenic tobacco plants expressed partial TMV movement gene and partial CMV replicase gene in the form of an intermolecular intron-hairpin RNA exhibited complete resistance to TMV or CMV infection.

  15. Inactivation of rabies virus.

    Science.gov (United States)

    Wu, Guanghui; Selden, David; Fooks, Anthony R; Banyard, Ashley

    2017-05-01

    Rabies virus is a notifiable pathogen that must be handled in high containment facilities where national and international guidelines apply. For the effective inactivation of rabies virus, a number of reagents were tested. Virkon S (1%) solution caused more than 4log reduction of rabies virus in culture medium supplemented with 10% foetal calf serum within 1min. Isopropyl alcohol (70%) treatment resulted in >3log reduction of rabies virus within 20s when applied at a ratio of 19:1, making it a suitable agent for surface decontamination whereas 70% ethanol was ineffective. Rabies virus (from 102.33 to 103ffu/ml) was also inactivated when cell cultures were fixed with 3% or 4% paraformaldehyde for 30min. Regardless of inactivation procedure, when taking inactivated virus preparations out of a biological containment envelope, proof of inocuity must be demonstrated to cover any possible error/deviation from procedure. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  16. Lujo virus: current concepts

    Directory of Open Access Journals (Sweden)

    Sewlall NH

    2017-12-01

    Full Text Available Nivesh H Sewlall,1,2 Janusz T Paweska2,3 1Department of Medicine, Morningside MediClinic, Johannesburg, South Africa; 2Department of Medicine, University of the Witwatersrand, Johannesburg, South Africa; 3Department of Medicine, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa Abstract: Lujo virus (LUJV, a novel Old World arenavirus, was found to cause a fulminant viral hemorrhagic fever syndrome in an outbreak in 2008. The primary patient was from Lusaka, Zambia, and subsequent nosocomial transmission occurred to four other patients in Johannesburg, South Africa, hence the name Lujo virus. Like all arenaviruses, LUJV is a segmented, single-stranded, negative-sense RNA virus. Genomic sequencing confirmed that LUJV G1 glycoprotein was novel, diverse and genetically equidistant from other arenaviruses. A clinical syndrome resembling severe, fulminant Lassa virus infection was responsible for a high case fatality rate of 80% (4/5 cases. This review describes briefly the clinical course of the disease, laboratory findings and diagnosis. Recent studies address the current aspects of epidemiology, pathophysiology and treatments, specifically comparing with Lassa virus. Keywords: Lujo virus, viral hemorrhagic fever, outbreak, epidemiology, pathophysiology, treatment

  17. Clinical characteristics of Human Immunodeficiency Virus (HIV ...

    African Journals Online (AJOL)

    Renal failure is a common finding in human immunodeficiency virus infected patients, and it contributes significantly to their morbidity and mortality. Most dialysis centres in Nigeria currently do not accept HIV positive patients for dialysis therapy for many reasons. The prevailing high level of stigmatization of HIV positive ...

  18. Transmission of Influenza A Viruses

    Science.gov (United States)

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to ‘novel’ viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

  19. Smaller Fleas: Viruses of Microorganisms

    Science.gov (United States)

    Hyman, Paul; Abedon, Stephen T.

    2012-01-01

    Life forms can be roughly differentiated into those that are microscopic versus those that are not as well as those that are multicellular and those that, instead, are unicellular. Cellular organisms seem generally able to host viruses, and this propensity carries over to those that are both microscopic and less than truly multicellular. These viruses of microorganisms, or VoMs, in fact exist as the world's most abundant somewhat autonomous genetic entities and include the viruses of domain Bacteria (bacteriophages), the viruses of domain Archaea (archaeal viruses), the viruses of protists, the viruses of microscopic fungi such as yeasts (mycoviruses), and even the viruses of other viruses (satellite viruses). In this paper we provide an introduction to the concept of viruses of microorganisms, a.k.a., viruses of microbes. We provide broad discussion particularly of VoM diversity. VoM diversity currently spans, in total, at least three-dozen virus families. This is roughly ten families per category—bacterial, archaeal, fungal, and protist—with some virus families infecting more than one of these microorganism major taxa. Such estimations, however, will vary with further discovery and taxon assignment and also are dependent upon what forms of life one includes among microorganisms. PMID:24278736

  20. Smaller Fleas: Viruses of Microorganisms

    Directory of Open Access Journals (Sweden)

    Paul Hyman

    2012-01-01

    Full Text Available Life forms can be roughly differentiated into those that are microscopic versus those that are not as well as those that are multicellular and those that, instead, are unicellular. Cellular organisms seem generally able to host viruses, and this propensity carries over to those that are both microscopic and less than truly multicellular. These viruses of microorganisms, or VoMs, in fact exist as the world’s most abundant somewhat autonomous genetic entities and include the viruses of domain Bacteria (bacteriophages, the viruses of domain Archaea (archaeal viruses, the viruses of protists, the viruses of microscopic fungi such as yeasts (mycoviruses, and even the viruses of other viruses (satellite viruses. In this paper we provide an introduction to the concept of viruses of microorganisms, a.k.a., viruses of microbes. We provide broad discussion particularly of VoM diversity. VoM diversity currently spans, in total, at least three-dozen virus families. This is roughly ten families per category—bacterial, archaeal, fungal, and protist—with some virus families infecting more than one of these microorganism major taxa. Such estimations, however, will vary with further discovery and taxon assignment and also are dependent upon what forms of life one includes among microorganisms.

  1. In vitro inhibition of monkeypox virus production and spread by Interferon-β

    Directory of Open Access Journals (Sweden)

    Johnston Sara C

    2012-01-01

    Full Text Available Abstract Background The Orthopoxvirus genus contains numerous virus species that are capable of causing disease in humans, including variola virus (the etiological agent of smallpox, monkeypox virus, cowpox virus, and vaccinia virus (the prototypical member of the genus. Monkeypox is a zoonotic disease that is endemic in the Democratic Republic of the Congo and is characterized by systemic lesion development and prominent lymphadenopathy. Like variola virus, monkeypox virus is a high priority pathogen for therapeutic development due to its potential to cause serious disease with significant health impacts after zoonotic, accidental, or deliberate introduction into a naïve population. Results The purpose of this study was to investigate the prophylactic and therapeutic potential of interferon-β (IFN-β for use against monkeypox virus. We found that treatment with human IFN-β results in a significant decrease in monkeypox virus production and spread in vitro. IFN-β substantially inhibited monkeypox virus when introduced 6-8 h post infection, revealing its potential for use as a therapeutic. IFN-β induced the expression of the antiviral protein MxA in infected cells, and constitutive expression of MxA was shown to inhibit monkeypox virus infection. Conclusions Our results demonstrate the successful inhibition of monkeypox virus using human IFN-β and suggest that IFN-β could potentially serve as a novel safe therapeutic for human monkeypox disease.

  2. Statistically significant relational data mining :

    Energy Technology Data Exchange (ETDEWEB)

    Berry, Jonathan W.; Leung, Vitus Joseph; Phillips, Cynthia Ann; Pinar, Ali; Robinson, David Gerald; Berger-Wolf, Tanya; Bhowmick, Sanjukta; Casleton, Emily; Kaiser, Mark; Nordman, Daniel J.; Wilson, Alyson G.

    2014-02-01

    This report summarizes the work performed under the project (3z(BStatitically significant relational data mining.(3y (BThe goal of the project was to add more statistical rigor to the fairly ad hoc area of data mining on graphs. Our goal was to develop better algorithms and better ways to evaluate algorithm quality. We concetrated on algorithms for community detection, approximate pattern matching, and graph similarity measures. Approximate pattern matching involves finding an instance of a relatively small pattern, expressed with tolerance, in a large graph of data observed with uncertainty. This report gathers the abstracts and references for the eight refereed publications that have appeared as part of this work. We then archive three pieces of research that have not yet been published. The first is theoretical and experimental evidence that a popular statistical measure for comparison of community assignments favors over-resolved communities over approximations to a ground truth. The second are statistically motivated methods for measuring the quality of an approximate match of a small pattern in a large graph. The third is a new probabilistic random graph model. Statisticians favor these models for graph analysis. The new local structure graph model overcomes some of the issues with popular models such as exponential random graph models and latent variable models.

  3. Determining Semantically Related Significant Genes.

    Science.gov (United States)

    Taha, Kamal

    2014-01-01

    GO relation embodies some aspects of existence dependency. If GO term xis existence-dependent on GO term y, the presence of y implies the presence of x. Therefore, the genes annotated with the function of the GO term y are usually functionally and semantically related to the genes annotated with the function of the GO term x. A large number of gene set enrichment analysis methods have been developed in recent years for analyzing gene sets enrichment. However, most of these methods overlook the structural dependencies between GO terms in GO graph by not considering the concept of existence dependency. We propose in this paper a biological search engine called RSGSearch that identifies enriched sets of genes annotated with different functions using the concept of existence dependency. We observe that GO term xcannot be existence-dependent on GO term y, if x- and y- have the same specificity (biological characteristics). After encoding into a numeric format the contributions of GO terms annotating target genes to the semantics of their lowest common ancestors (LCAs), RSGSearch uses microarray experiment to identify the most significant LCA that annotates the result genes. We evaluated RSGSearch experimentally and compared it with five gene set enrichment systems. Results showed marked improvement.

  4. Significant improvements in children's health.

    Science.gov (United States)

    Tam, L

    1994-01-01

    The field report from PLAN field offices in Sucre and Altiplano in Bolivia, Santo Domingo in the Dominican Republic, and Amatitlan in Guatemala provides a summary of survey results pertaining to diarrheal disease control, immunizations, and nutrition. The PLAN sites are rural with the exception of the periurban slum surrounding Santo Domingo, which has better access to health services. Interviews were conducted among mothers with children aged 0-23 months in project areas, with the exception of Altiplano and Santo Domingo which included nonproject areas for comparative purposes. The results for diarrhea disease control are that an estimated 90% of episodes can be successfully treated at home. Evaluation is made of the timeliness and coverage of immunizations, the degree of management of diarrhea at home and at the health facility, and the extent of exclusive breast feeding in the first 4 months, and total breast feeding with food supplementation in the first year of life. The conclusion is that the four field offices make a significant and positive impact on children aged 0-23 months.

  5. Statistical significance for hierarchical clustering.

    Science.gov (United States)

    Kimes, Patrick K; Liu, Yufeng; Neil Hayes, David; Marron, James Stephen

    2017-09-01

    Cluster analysis has proved to be an invaluable tool for the exploratory and unsupervised analysis of high-dimensional datasets. Among methods for clustering, hierarchical approaches have enjoyed substantial popularity in genomics and other fields for their ability to simultaneously uncover multiple layers of clustering structure. A critical and challenging question in cluster analysis is whether the identified clusters represent important underlying structure or are artifacts of natural sampling variation. Few approaches have been proposed for addressing this problem in the context of hierarchical clustering, for which the problem is further complicated by the natural tree structure of the partition, and the multiplicity of tests required to parse the layers of nested clusters. In this article, we propose a Monte Carlo based approach for testing statistical significance in hierarchical clustering which addresses these issues. The approach is implemented as a sequential testing procedure guaranteeing control of the family-wise error rate. Theoretical justification is provided for our approach, and its power to detect true clustering structure is illustrated through several simulation studies and applications to two cancer gene expression datasets. © 2017, The International Biometric Society.

  6. Biology, etiology, and control of virus diseases of banana and plantain.

    Science.gov (United States)

    Kumar, P Lava; Selvarajan, Ramasamy; Iskra-Caruana, Marie-Line; Chabannes, Matthieu; Hanna, Rachid

    2015-01-01

    Banana and plantain (Musa spp.), produced in 10.3 million ha in the tropics, are among the world's top 10 food crops. They are vegetatively propagated using suckers or tissue culture plants and grown almost as perennial plantations. These are prone to the accumulation of pests and pathogens, especially viruses which contribute to yield reduction and are also barriers to the international exchange of germplasm. The most economically important viruses of banana and plantain are Banana bunchy top virus (BBTV), a complex of banana streak viruses (BSVs) and Banana bract mosaic virus (BBrMV). BBTV is known to cause the most serious economic losses in the "Old World," contributing to a yield reduction of up to 100% and responsible for a dramatic reduction in cropping area. The BSVs exist as episomal and endogenous forms are known to be worldwide in distribution. In India and the Philippines, BBrMV is known to be economically important but recently the virus was discovered in Colombia and Costa Rica, thus signaling its spread into the "New World." Banana and plantain are also known to be susceptible to five other viruses of minor significance, such as Abaca mosaic virus, Abaca bunchy top virus, Banana mild mosaic virus, Banana virus X, and Cucumber mosaic virus. Studies over the past 100 years have contributed to important knowledge on disease biology, distribution, and spread. Research during the last 25 years have led to a better understanding of the virus-vector-host interactions, virus diversity, disease etiology, and epidemiology. In addition, new diagnostic tools were developed which were used for surveillance and the certification of planting material. Due to a lack of durable host resistance in the Musa spp., phytosanitary measures and the use of virus-free planting material are the major methods of virus control. The state of knowledge on BBTV, BBrMV, and BSVs, and other minor viruses, disease spread, and control are summarized in this review. © 2015 Elsevier Inc

  7. Statistical significance of quantitative PCR

    Directory of Open Access Journals (Sweden)

    Mazza Christian

    2007-04-01

    Full Text Available Abstract Background PCR has the potential to detect and precisely quantify specific DNA sequences, but it is not yet often used as a fully quantitative method. A number of data collection and processing strategies have been described for the implementation of quantitative PCR. However, they can be experimentally cumbersome, their relative performances have not been evaluated systematically, and they often remain poorly validated statistically and/or experimentally. In this study, we evaluated the performance of known methods, and compared them with newly developed data processing strategies in terms of resolution, precision and robustness. Results Our results indicate that simple methods that do not rely on the estimation of the efficiency of the PCR amplification may provide reproducible and sensitive data, but that they do not quantify DNA with precision. Other evaluated methods based on sigmoidal or exponential curve fitting were generally of both poor resolution and precision. A statistical analysis of the parameters that influence efficiency indicated that it depends mostly on the selected amplicon and to a lesser extent on the particular biological sample analyzed. Thus, we devised various strategies based on individual or averaged efficiency values, which were used to assess the regulated expression of several genes in response to a growth factor. Conclusion Overall, qPCR data analysis methods differ significantly in their performance, and this analysis identifies methods that provide DNA quantification estimates of high precision, robustness and reliability. These methods allow reliable estimations of relative expression ratio of two-fold or higher, and our analysis provides an estimation of the number of biological samples that have to be analyzed to achieve a given precision.

  8. Avian Influenza A Virus Infections in Humans

    Science.gov (United States)

    ... Pandemic Other Avian Influenza A Virus Infections in Humans Language: English (US) Español Recommend on Facebook Tweet ... A Viruses Avian Influenza A Virus Infections in Humans Although avian influenza A viruses usually do not ...

  9. [Zika virus infection during pregnancy].

    Science.gov (United States)

    Picone, O; Vauloup-Fellous, C; D'Ortenzio, E; Huissoud, C; Carles, G; Benachi, A; Faye, A; Luton, D; Paty, M-C; Ayoubi, J-M; Yazdanpanah, Y; Mandelbrot, L; Matheron, S

    2016-05-01

    A Zika virus epidemic is currently ongoing in the Americas. This virus is linked to congenital infections with potential severe neurodevelopmental dysfunction. However, incidence of fetal infection and whether this virus is responsible of other fetal complications are still unknown. National and international public health authorities recommend caution and several prevention measures. Declaration of Zika virus infection is now mandatory in France. Given the available knowledge on Zika virus, we suggest here a review of the current recommendations for management of pregnancy in case of suspicious or infection by Zika virus in a pregnant woman. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. Biogenesis, Function and Applications of Virus-Derived Small RNAs in Plants

    Directory of Open Access Journals (Sweden)

    Chao eZhang

    2015-11-01

    Full Text Available RNA silencing, an evolutionarily conserved and sequence-specific gene-inactivation system, has a pivotal role in antiviral defense in most eukaryotic organisms. In plants, a class of exogenous small RNAs (sRNAs originating from the infecting virus called virus-derived small interfering RNAs (vsiRNAs are predominantly responsible for RNA silencing-mediated antiviral immunity. Nowadays, the process of vsiRNA formation and the role of vsiRNAs in plant viral defense have been revealed through deep sequencing of sRNAs and diverse genetic analysis. The biogenesis of vsiRNAs is analogous to that of endogenous sRNAs, which require diverse essential components including DICER-LIKE (DCL, ARGONAUTE (AGO, and RNA-dependent RNA polymerase (RDR proteins. vsiRNAs trigger antiviral defense through post-transcriptional gene silencing (PTGS or transcriptional gene silencing (TGS of viral RNA, and they hijack the host RNA silencing system to target complementary host transcripts. Additionally, several applications that take advantage of the current knowledge of vsiRNAs research are being used, such as breeding antiviral plants through genetic engineering technology, reconstructing of viral genomes, and surveying viral ecology and populations. Here, we will provide an overview of vsiRNA pathways, with a primary focus on the advances in vsiRNA biogenesis and function, and discuss their potential applications as well as the future challenges in vsiRNAs research.

  11. GB virus C/hepatitis G virus (GBV-C/HGV): still looking for a disease.

    Science.gov (United States)

    Sathar, M; Soni, P; York, D

    2000-10-01

    GB Virus C and Hepatitis G Virus (GBV-C/HGV) are positive, single-stranded flaviviruses. GBV-C and HGV are independent isolates of the same virus. Transmission via the blood-borne route is the commonest mode, although vertical and sexual transmission is well documented. GBV-C/HGV is distributed globally; its prevalence in the general population is 10 fold higher in African countries than in non-African countries. High prevalences of GBV-C/HGV have been found in subjects with frequent parenteral exposure and in groups at high risk of exposure to blood and blood products. The clinical significance of human infection with GBV-C/HGV is currently unclear. The virus can establish both acute and chronic infection and appears to be sensitive to interferon. Only some 12-15% of chronic Non-A, B, C hepatitis cases are infected with GBV-C/HGV. A direct association with liver pathology is still lacking and it is not yet clear as to whether GBV-C/HGV is indeed a hepatotropic virus. Current evidence suggests that the spectrum of association of GBV-C/HGV infection with extrahepatic diseases ranges from haematalogical diseases, aplastic anaemia, human immunodeficiency virus (HIV)-positive idiopathic thrombocytopenia and thalassemia, through to common variable immune deficiency and cryoglobunemia.

  12. Caveolin-1 interacts with the Gag precursor of murine leukaemia virus and modulates virus production

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    Koester Mario

    2006-09-01

    Full Text Available Abstract Background Retroviral Gag determines virus assembly at the plasma membrane and the formation of virus-like particles in intracellular multivesicular bodies. Thereby, retroviruses exploit by interaction with cellular partners the cellular machineries for vesicular transport in various ways. Results The retroviral Gag precursor protein drives assembly of murine leukaemia viruses (MLV at the plasma membrane (PM and the formation of virus like particles in multivesicular bodies (MVBs. In our study we show that caveolin-1 (Cav-1, a multifunctional membrane-associated protein, co-localizes with Gag in a punctate pattern at the PM of infected NIH 3T3 cells. We provide evidence that Cav-1 interacts with the matrix protein (MA of the Gag precursor. This interaction is mediated by a Cav-1 binding domain (CBD within the N-terminus of MA. Interestingly, the CBD motif identified within MA is highly conserved among most other γ-retroviruses. Furthermore, Cav-1 is incorporated into MLV released from NIH 3T3 cells. Overexpression of a GFP fusion protein containing the putative CBD of the retroviral MA resulted in a considerable decrease in production of infectious retrovirus. Moreover, expression of a dominant-negative Cav-1 mutant affected retroviral titres significantly. Conclusion This study demonstrates that Cav-1 interacts with MLV Gag, co-localizes with Gag at the PM and affects the production of infectious virus. The results strongly suggest a role for Cav-1 in the process of virus assembly.

  13. Japanese encephalitis virus vaccine candidates generated by chimerization with dengue virus type 4.

    Science.gov (United States)

    Gromowski, Gregory D; Firestone, Cai-Yen; Hanson, Christopher T; Whitehead, Stephen S

    2014-05-23

    Japanese encephalitis virus (JEV) is a leading cause of viral encephalitis worldwide and vaccination is one of the most effective ways to prevent disease. A suitable live-attenuated JEV vaccine could be formulated with a live-attenuated tetravalent dengue vaccine for the control of these viruses in endemic areas. Toward this goal, we generated chimeric virus vaccine candidates by replacing the precursor membrane (prM) and envelope (E) protein structural genes of recombinant dengue virus type 4 (rDEN4) or attenuated vaccine candidate rDEN4Δ30 with those of wild-type JEV strain India/78. Mutations were engineered in E, NS3 and NS4B protein genes to improve replication in Vero cells. The chimeric viruses were attenuated in mice and some elicited modest but protective levels of immunity after a single dose. One particular chimeric virus, bearing E protein mutation Q264H, replicated to higher titer in tissue culture and was significantly more immunogenic in mice. The results are compared with live-attenuated JEV vaccine strain SA14-14-2. Published by Elsevier Ltd.

  14. Mulches reduce aphid-borne viruses and whiteflies in cantaloupe

    OpenAIRE

    Summers, Charles G.; Mitchell, Jeffrey P.; Stapleton, James J.

    2005-01-01

    We compared reflective plastic and wheat straw mulches with conventional bare soil for managing aphid-borne virus diseases and silverleaf whitefly in cantaloupe. The occurrence of aphid-borne virus diseases was significantly reduced with both mulches as opposed to bare soil, and reflective plastic performed better than wheat straw. Silverleaf whitefly numbers, both adults and nymphs, were reduced equally by plastic mulch and wheat straw, and were significantly lower than with bare soil. Refle...

  15. Comparison of immune responses to attenuated rabies virus and street virus in mouse brain.

    Science.gov (United States)

    Miao, Fa-Ming; Zhang, Shou-Feng; Wang, Shu-Chao; Liu, Ye; Zhang, Fei; Hu, Rong-Liang

    2017-01-01

    Rabies is a lethal neurological disease caused by the neurotropic rabies virus (RABV). To investigate the innate immune response in the brain during rabies infection, key gene transcripts indicative of innate immunity in a mouse model system were measured using real-time RT-PCR. Mice were infected via the intracerebral or intramuscular route with either attenuated rabies virus (SRV9) or pathogenic rabies virus (BD06). Infection with SRV9 resulted in the early detection of viral replication and the rapid induction of innate immune response gene expression in the brain. BD06 infection elicited innate immune response gene expression during only the late stage of infection. We measured Na-fluorescein uptake to assess blood-brain barrier (BBB) permeability, which was enhanced during the early stage of SRV9 infection and significantly enhanced during the late stage of BD06 infection. Furthermore, early SRV9 replication increased the maturation and differentiation of dendritic cells (DCs) and B cells in the inguinal lymph nodes and initiated the generation of virus-neutralizing antibodies (VNAs), which cooperate with the innate immune response to eliminate virus from the CNS. However, BD06 infection did not stimulate VNA production; thus, the virus was able to evade the host immune response and cause encephalitis. The rabies virus phosphoprotein has been reported to counteract IFN activation. In an in vitro study of the relationship between IFN antagonism and RABV pathogenicity, we demonstrated that SRV9 more strongly antagonized IFN activity than did BD06. Therefore, there is no positive relationship between the IFN antagonist activity of the virus and its pathogenicity.

  16. Programmed ribosomal frameshift alters expression of west nile virus genes and facilitates virus replication in birds and mosquitoes.

    Directory of Open Access Journals (Sweden)

    Ezequiel Balmori Melian

    2014-11-01

    Full Text Available West Nile virus (WNV is a human pathogen of significant medical importance with close to 40,000 cases of encephalitis and more than 1,600 deaths reported in the US alone since its first emergence in New York in 1999. Previous studies identified a motif in the beginning of non-structural gene NS2A of encephalitic flaviviruses including WNV which induces programmed -1 ribosomal frameshift (PRF resulting in production of an additional NS protein NS1'. We have previously demonstrated that mutant WNV with abolished PRF was attenuated in mice. Here we have extended our previous observations by showing that PRF does not appear to have a significant role in virus replication, virion formation, and viral spread in several cell lines in vitro. However, we have also shown that PRF induces an over production of structural proteins over non-structural proteins in virus-infected cells and that mutation abolishing PRF is present in ∼11% of the wild type virus population. In vivo experiments in house sparrows using wild type and PRF mutant of New York 99 strain of WNV viruses showed some attenuation for the PRF mutant virus. Moreover, PRF mutant of Kunjin strain of WNV showed significant decrease compared to wild type virus infection in dissemination of the virus from the midgut through the haemocoel, and ultimately the capacity of infected mosquitoes to transmit virus. Thus our results demonstrate an important role for PRF in regulating expression of viral genes and consequently virus replication in avian and mosquito hosts.

  17. Viruses, definitions and reality

    Directory of Open Access Journals (Sweden)

    Libia Herrero-Uribe

    2011-09-01

    Full Text Available Viruses are known to be abundant, ubiquitous, and to play a very important role in the health and evolution of life organisms. However, most biologists have considered them as entities separate from the realm of life and acting merely as mechanical artifacts that can exchange genes between different organisms. This article reviews some definitions of life organisms to determine if viruses adjust to them, and additionally, considers new discoveries to challenge the present definition of viruses. Definitions of life organisms have been revised in order to validate how viruses fit into them. Viral factories are discussed since these mini-organelles are a good example of the complexity of viral infection, not as a mechanical usurpation of cell structures, but as a driving force leading to the reorganization and modification of cell structures by viral and cell enzymes. New discoveries such as the Mimivirus, its virophage and viruses that produce filamentous tails when outside of their host cell, have stimulated the scientific community to analyze the current definition of viruses. One way to be free for innovation is to learn from life, without rigid mental structures or tied to the past, in order to understand in an integrated view the new discoveries that will be unfolded in future research. Life processes must be looked from the complexity and trans-disciplinarity perspective that includes and accepts the temporality of the active processes of life organisms, their interdependency and interrelation among them and their environment. New insights must be found to redefine life organisms, especially viruses, which still are defined using the same concepts and knowledge of the fifties. Rev. Biol. Trop. 59 (3: 993-998. Epub 2011 September 01.

  18. Viruses, definitions and reality.

    Science.gov (United States)

    Herrero-Uribe, Libia

    2011-09-01

    Viruses are known to be abundant, ubiquitous, and to play a very important role in the health and evolution of life organisms. However, most biologists have considered them as entities separate from the realm of life and acting merely as mechanical artifacts that can exchange genes between different organisms. This article reviews some definitions of life organisms to determine if viruses adjust to them, and additionally, considers new discoveries to challenge the present definition of viruses. Definitions of life organisms have been revised in order to validate how viruses fit into them. Viral factories are discussed since these mini-organelles are a good example of the complexity of viral infection, not as a mechanical usurpation of cell structures, but as a driving force leading to the reorganization and modification of cell structures by viral and cell enzymes. New discoveries such as the Mimivirus, its virophage and viruses that produce filamentous tails when outside of their host cell, have stimulated the scientific community to analyze the current definition of viruses. One way to be free for innovation is to learn from life, without rigid mental structures or tied to the past, in order to understand in an integrated view the new discoveries that will be unfolded in future research. Life processes must be looked from the complexity and trans-disciplinarity perspective that includes and accepts the temporality of the active processes of life organisms, their interdependency and interrelation among them and their environment. New insights must be found to redefine life organisms, especially viruses, which still are defined using the same concepts and knowledge of the fifties.

  19. Genetic variation and significance of hepatitis B surface antigen

    Directory of Open Access Journals (Sweden)

    ZHANG Zhenhua

    2013-11-01

    Full Text Available Hepatitis B virus (HBV is prone to genetic variation because there is reverse transcription in the process of HBV replication. The gene mutation of hepatitis B surface antigen may affect clinical diagnosis of HBV infection, viral replication, and vaccine effect. The current research and existing problems are discussed from the following aspects: the mechanism and biological and clinical significance of S gene mutation. Most previous studies focused on S gene alone, so S gene should be considered as part of HBV DNA in the future research on S gene mutation.

  20. Embryo transfer from cattle infected with bluetongue virus.

    Science.gov (United States)

    Bowen, R A; Howard, T H; Elsden, R P; Seidel, G E

    1983-09-01

    Embryos recovered nonsurgically from donor cattle during the peak of bluetongue viremia were surgically transferred to seronegative recipients 7 to 8 or 10 to 11 days after the onset of donor estrus. Virus was isolated from the uterine flushing medium recovered from 11 of the 20 donors. Bluetongue virus was not isolated from the blood of any of 39 recipients, nor did any recipient seroconvert to the virus following transfer. The number of recipients that became pregnant after transfer of embryos from infected donors (21 of 39) was not significantly different from contemporary controls. Virus antigen was not detected by immunofluorescence in any of 63 embryos and oocytes recovered from viremic donors. These results indicate that under standard embryo transfer conditions, transmission of bluetongue virus from infected donors to uninfected recipients is unlikely to occur.