Good Friends, Bad News - Affect and Virality in Twitter

DEFF Research Database (Denmark)

Hansen, Lars Kai; Arvidsson, Adam; Nielsen, Finn Årup

2011-01-01

The link between affect, defined as the capacity for sentimental arousal on the part of a message, and virality, defined as the probability that it be sent along, is of significant theoretical and practical importance, e.g. for viral marketing. The basic measure of virality in Twitter is the prob......The link between affect, defined as the capacity for sentimental arousal on the part of a message, and virality, defined as the probability that it be sent along, is of significant theoretical and practical importance, e.g. for viral marketing. The basic measure of virality in Twitter...

ViralORFeome: an integrated database to generate a versatile collection of viral ORFs.

Science.gov (United States)

Pellet, J; Tafforeau, L; Lucas-Hourani, M; Navratil, V; Meyniel, L; Achaz, G; Guironnet-Paquet, A; Aublin-Gex, A; Caignard, G; Cassonnet, P; Chaboud, A; Chantier, T; Deloire, A; Demeret, C; Le Breton, M; Neveu, G; Jacotot, L; Vaglio, P; Delmotte, S; Gautier, C; Combet, C; Deleage, G; Favre, M; Tangy, F; Jacob, Y; Andre, P; Lotteau, V; Rabourdin-Combe, C; Vidalain, P O

2010-01-01

Large collections of protein-encoding open reading frames (ORFs) established in a versatile recombination-based cloning system have been instrumental to study protein functions in high-throughput assays. Such 'ORFeome' resources have been developed for several organisms but in virology, plasmid collections covering a significant fraction of the virosphere are still needed. In this perspective, we present ViralORFeome 1.0 (http://www.viralorfeome.com), an open-access database and management system that provides an integrated set of bioinformatic tools to clone viral ORFs in the Gateway(R) system. ViralORFeome provides a convenient interface to navigate through virus genome sequences, to design ORF-specific cloning primers, to validate the sequence of generated constructs and to browse established collections of virus ORFs. Most importantly, ViralORFeome has been designed to manage all possible variants or mutants of a given ORF so that the cloning procedure can be applied to any emerging virus strain. A subset of plasmid constructs generated with ViralORFeome platform has been tested with success for heterologous protein expression in different expression systems at proteome scale. ViralORFeome should provide our community with a framework to establish a large collection of virus ORF clones, an instrumental resource to determine functions, activities and binding partners of viral proteins.

Anti-respiratory syncytial virus (RSV) G monoclonal antibodies reduce lung inflammation and viral lung titers when delivered therapeutically in a BALB/c mouse model.

Science.gov (United States)

Caidi, Hayat; Miao, Congrong; Thornburg, Natalie J; Tripp, Ralph A; Anderson, Larry J; Haynes, Lia M

2018-06-01

RSV continues to be a high priority for vaccine and antiviral drug development. Unfortunately, no safe and effective RSV vaccine is available and treatment options are limited. Over the past decade, several studies have focused on the role of RSV G protein on viral entry, viral neutralization, and RSV-mediated pathology. Anti-G murine monoclonal antibody (mAb) 131-2G treatment has been previously shown to reduce weight loss, bronchoalveolar lavage (BAL) cell number, airway reactivity, and Th2-type cytokine production in RSV-infected mice more rapidly than a commercial humanized monoclonal antibody (mAb) against RSV F protein (Palivizumab). In this study, we have tested two human anti-RSV G mAbs, 2B11 and 3D3, by both prophylactic and therapeutic treatment for RSV in the BALB/c mouse model. Both anti-G mAbs reduced viral load, leukocyte infiltration and IFN-γ and IL-4 expression in cell-free BAL supernatants emphasizing the potential of anti-G mAbs as anti-inflammatory and antiviral strategies. Published by Elsevier B.V.

A Reference Viral Database (RVDB) To Enhance Bioinformatics Analysis of High-Throughput Sequencing for Novel Virus Detection.

Science.gov (United States)

Goodacre, Norman; Aljanahi, Aisha; Nandakumar, Subhiksha; Mikailov, Mike; Khan, Arifa S

2018-01-01

Detection of distantly related viruses by high-throughput sequencing (HTS) is bioinformatically challenging because of the lack of a public database containing all viral sequences, without abundant nonviral sequences, which can extend runtime and obscure viral hits. Our reference viral database (RVDB) includes all viral, virus-related, and virus-like nucleotide sequences (excluding bacterial viruses), regardless of length, and with overall reduced cellular sequences. Semantic selection criteria (SEM-I) were used to select viral sequences from GenBank, resulting in a first-generation viral database (VDB). This database was manually and computationally reviewed, resulting in refined, semantic selection criteria (SEM-R), which were applied to a new download of updated GenBank sequences to create a second-generation VDB. Viral entries in the latter were clustered at 98% by CD-HIT-EST to reduce redundancy while retaining high viral sequence diversity. The viral identity of the clustered representative sequences (creps) was confirmed by BLAST searches in NCBI databases and HMMER searches in PFAM and DFAM databases. The resulting RVDB contained a broad representation of viral families, sequence diversity, and a reduced cellular content; it includes full-length and partial sequences and endogenous nonretroviral elements, endogenous retroviruses, and retrotransposons. Testing of RVDBv10.2, with an in-house HTS transcriptomic data set indicated a significantly faster run for virus detection than interrogating the entirety of the NCBI nonredundant nucleotide database, which contains all viral sequences but also nonviral sequences. RVDB is publically available for facilitating HTS analysis, particularly for novel virus detection. It is meant to be updated on a regular basis to include new viral sequences added to GenBank. IMPORTANCE To facilitate bioinformatics analysis of high-throughput sequencing (HTS) data for the detection of both known and novel viruses, we have

Sucralfate significantly reduces ciprofloxacin concentrations in serum.

OpenAIRE

Garrelts, J C; Godley, P J; Peterie, J D; Gerlach, E H; Yakshe, C C

1990-01-01

The effect of sucralfate on the bioavailability of ciprofloxacin was evaluated in eight healthy subjects utilizing a randomized, crossover design. The area under the concentration-time curve from 0 to 12 h was reduced from 8.8 to 1.1 micrograms.h/ml by sucralfate (P less than 0.005). Similarly, the maximum concentration of ciprofloxacin in serum was reduced from 2.0 to 0.2 micrograms/ml (P less than 0.005). We conclude that concurrent ingestion of sucralfate significantly reduces the concentr...

Clinical significance of detection of serum markers of several viral infections in hospitalized patients before blood exposure

International Nuclear Information System (INIS)

Hong Kai; Chen Linxing; Chen Yichang; Ding Yingshu

2005-01-01

Objective: To explore the desirability of setting a routine of test for detection of the serum markers of several viral infections hospitalized patients before anticipated blood exposure. Methods: Serum levels of five HBV markers, anti-HCV, anti-HIV (with ELISA) and ALT were determined in 214 hospitalized patients before forthcoming blood exposure as well as in 2468 controls. Results: The positive rate of each of the above-mentioned markers in the patients was: HBsAg 15.2% (397/2614), HBcAb- IgG 72.5% (1895/2614), anti-HCV 3.91% (102/2614), anti- HIV 0.08% (2/2614) and ALT level was above 40 u in 8.7% of the patients (227/2614). Each of the positive rate was significantly higher than that in the controls. Conclusion: There is a substantial portion of subjects harboring viral infections in the hospitalized patients. It is imperative to have these patients identified before blood exposure so that proper cautions can be taken and preventive measures implemented to minimize possible nosocomial as well as patients-to-staff infections. Moreover, any potential legal problems can also be appropriately dealt with. (authors)

Origins and challenges of viral dark matter.

Science.gov (United States)

Krishnamurthy, Siddharth R; Wang, David

2017-07-15

The accurate classification of viral dark matter - metagenomic sequences that originate from viruses but do not align to any reference virus sequences - is one of the major obstacles in comprehensively defining the virome. Depending on the sample, viral dark matter can make up from anywhere between 40 and 90% of sequences. This review focuses on the specific nature of dark matter as it relates to viral sequences. We identify three factors that contribute to the existence of viral dark matter: the divergence and length of virus sequences, the limitations of alignment based classification, and limited representation of viruses in reference sequence databases. We then discuss current methods that have been developed to at least partially circumvent these limitations and thereby reduce the extent of viral dark matter. Copyright © 2017 Elsevier B.V. All rights reserved.

A Herpesviral Immediate Early Protein Promotes Transcription Elongation of Viral Transcripts.

Science.gov (United States)

Fox, Hannah L; Dembowski, Jill A; DeLuca, Neal A

2017-06-13

Herpes simplex virus 1 (HSV-1) genes are transcribed by cellular RNA polymerase II (RNA Pol II). While four viral immediate early proteins (ICP4, ICP0, ICP27, and ICP22) function in some capacity in viral transcription, the mechanism by which ICP22 functions remains unclear. We observed that the FACT complex (comprised of SSRP1 and Spt16) was relocalized in infected cells as a function of ICP22. ICP22 was also required for the association of FACT and the transcription elongation factors SPT5 and SPT6 with viral genomes. We further demonstrated that the FACT complex interacts with ICP22 throughout infection. We therefore hypothesized that ICP22 recruits cellular transcription elongation factors to viral genomes for efficient transcription elongation of viral genes. We reevaluated the phenotype of an ICP22 mutant virus by determining the abundance of all viral mRNAs throughout infection by transcriptome sequencing (RNA-seq). The accumulation of almost all viral mRNAs late in infection was reduced compared to the wild type, regardless of kinetic class. Using chromatin immunoprecipitation sequencing (ChIP-seq), we mapped the location of RNA Pol II on viral genes and found that RNA Pol II levels on the bodies of viral genes were reduced in the ICP22 mutant compared to wild-type virus. In contrast, the association of RNA Pol II with transcription start sites in the mutant was not reduced. Taken together, our results indicate that ICP22 plays a role in recruiting elongation factors like the FACT complex to the HSV-1 genome to allow for efficient viral transcription elongation late in viral infection and ultimately infectious virion production. IMPORTANCE HSV-1 interacts with many cellular proteins throughout productive infection. Here, we demonstrate the interaction of a viral protein, ICP22, with a subset of cellular proteins known to be involved in transcription elongation. We determined that ICP22 is required to recruit the FACT complex and other transcription

A Herpesviral Immediate Early Protein Promotes Transcription Elongation of Viral Transcripts

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Hannah L. Fox

2017-06-01

Full Text Available Herpes simplex virus 1 (HSV-1 genes are transcribed by cellular RNA polymerase II (RNA Pol II. While four viral immediate early proteins (ICP4, ICP0, ICP27, and ICP22 function in some capacity in viral transcription, the mechanism by which ICP22 functions remains unclear. We observed that the FACT complex (comprised of SSRP1 and Spt16 was relocalized in infected cells as a function of ICP22. ICP22 was also required for the association of FACT and the transcription elongation factors SPT5 and SPT6 with viral genomes. We further demonstrated that the FACT complex interacts with ICP22 throughout infection. We therefore hypothesized that ICP22 recruits cellular transcription elongation factors to viral genomes for efficient transcription elongation of viral genes. We reevaluated the phenotype of an ICP22 mutant virus by determining the abundance of all viral mRNAs throughout infection by transcriptome sequencing (RNA-seq. The accumulation of almost all viral mRNAs late in infection was reduced compared to the wild type, regardless of kinetic class. Using chromatin immunoprecipitation sequencing (ChIP-seq, we mapped the location of RNA Pol II on viral genes and found that RNA Pol II levels on the bodies of viral genes were reduced in the ICP22 mutant compared to wild-type virus. In contrast, the association of RNA Pol II with transcription start sites in the mutant was not reduced. Taken together, our results indicate that ICP22 plays a role in recruiting elongation factors like the FACT complex to the HSV-1 genome to allow for efficient viral transcription elongation late in viral infection and ultimately infectious virion production.

Viral infections, prevalence and costs: A5-year, hospital based, retrospective observational study in shiraz, iran

International Nuclear Information System (INIS)

Sabayan, B.; Zamiri, N.; Chohedry, A.

2007-01-01

Many patients suffering from viral infections attend to health care centers. Data gathered from viral infections is limited to specific cases such as AIDS, viral hepatitis and Influenza. There is a significant lack of reliable documentation about other viral infections. In this study the prevalence and related costs of viral infections in hospitals of Shiraz University of Medical Sciences were reviewed. In this cross-sectional study the data were extracted from files of 1319 patients with viral infection admitted in two university hospitals during a five year period (1999-2004). The frequencies of different viral infections along with their demographic data were analyzed. The mean age of the patients was 29.24 with the range of 90 years. Hospitalization days were 8636 in 40 different wards in two hospitals. US$ 30.84 was the daily mean cost for each admitted patient. Viral meningitis was most frequent (14.2%) and 8.4% of patients died during hospitalization. This study confirms the necessity of expanding management programs for viral infections especially hepatitis B in youths in Iran. Unspecified viral infections cost much more than specified viral diseases. Viral infection costs can be reduced by finding more sensitive and specific diagnostic methods. (author)

Soluble rhesus lymphocryptovirus gp350 protects against infection and reduces viral loads in animals that become infected with virus after challenge.

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Junji Sashihara

2011-10-01

Full Text Available Epstein-Barr virus (EBV is a human lymphocryptovirus that is associated with several malignancies. Elevated EBV DNA in the blood is observed in transplant recipients prior to, and at the time of post-transplant lymphoproliferative disease; thus, a vaccine that either prevents EBV infection or lowers the viral load might reduce certain EBV malignancies. Two major approaches have been suggested for an EBV vaccine- immunization with either EBV glycoprotein 350 (gp350 or EBV latency proteins (e.g. EBV nuclear antigens [EBNAs]. No comparative trials, however, have been performed. Rhesus lymphocryptovirus (LCV encodes a homolog for each gene in EBV and infection of monkeys reproduces the clinical, immunologic, and virologic features of both acute and latent EBV infection. We vaccinated rhesus monkeys at 0, 4 and 12 weeks with (a soluble rhesus LCV gp350, (b virus-like replicon particles (VRPs expressing rhesus LCV gp350, (c VRPs expressing rhesus LCV gp350, EBNA-3A, and EBNA-3B, or (d PBS. Animals vaccinated with soluble gp350 produced higher levels of antibody to the glycoprotein than those vaccinated with VRPs expressing gp350. Animals vaccinated with VRPs expressing EBNA-3A and EBNA-3B developed LCV-specific CD4 and CD8 T cell immunity to these proteins, while VRPs expressing gp350 did not induce detectable T cell immunity to gp350. After challenge with rhesus LCV, animals vaccinated with soluble rhesus LCV gp350 had the best level of protection against infection based on seroconversion, viral DNA, and viral RNA in the blood after challenge. Surprisingly, animals vaccinated with gp350 that became infected had the lowest LCV DNA loads in the blood at 23 months after challenge. These studies indicate that gp350 is critical for both protection against infection with rhesus LCV and for reducing the viral load in animals that become infected after challenge. Our results suggest that additional trials with soluble EBV gp350 alone, or in combination with

Lymphocytes Negatively Regulate NK Cell Activity via Qa-1b following Viral Infection

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Haifeng C. Xu

2017-11-01

Full Text Available NK cells can reduce anti-viral T cell immunity during chronic viral infections, including infection with the lymphocytic choriomeningitis virus (LCMV. However, regulating factors that maintain the equilibrium between productive T cell and NK cell immunity are poorly understood. Here, we show that a large viral load resulted in inhibition of NK cell activation, which correlated with increased expression of Qa-1b, a ligand for inhibitory NK cell receptors. Qa-1b was predominantly upregulated on B cells following LCMV infection, and this upregulation was dependent on type I interferons. Absence of Qa-1b resulted in increased NK cell-mediated regulation of anti-viral T cells following viral infection. Consequently, anti-viral T cell immunity was reduced in Qa-1b- and NKG2A-deficient mice, resulting in increased viral replication and immunopathology. NK cell depletion restored anti-viral immunity and virus control in the absence of Qa-1b. Taken together, our findings indicate that lymphocytes limit NK cell activity during viral infection in order to promote anti-viral T cell immunity.

Dysplastic hepatocytes develop nuclear inclusions in a mouse model of viral hepatitis.

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Priyanka Thakur

Full Text Available Viral hepatitis resulting in chronic liver disease is an important clinical challenge and insight into the cellular processes that drive pathogenesis will be critical in order to develop new diagnostic and therapeutic options. Nuclear inclusions in viral and non-viral hepatitis are well documented and have diagnostic significance in some disease contexts. However, the origins and functional consequences of these nuclear inclusions remain elusive. To date the clinical observation of nuclear inclusions in viral and non-viral hepatitis has not been explored at depth in murine models of liver disease. Herein, we report that in a transgenic model of hepatitis B surface antigen mediated hepatitis, murine hepatocytes exhibit nuclear inclusions. Cells bearing nuclear inclusions were more likely to express markers of cell proliferation. We also established a correlation between these inclusions and oxidative stress. N-acetyl cysteine treatment effectively reduced oxidative stress levels, relieved endoplasmic reticulum (ER stress, and the number of nuclear inclusions we observed in the transgenic mice. Our results suggest that the presence of nuclear inclusions in hepatocytes correlates with oxidative stress and cellular proliferation in a model of antigen mediated hepatitis.

Beyond viral suppression of HIV

DEFF Research Database (Denmark)

Lazarus, Jeffrey V.; Safreed-Harmon, Kelly; Barton, Simon E

2016-01-01

BACKGROUND: In 2016, the World Health Organization (WHO) adopted a new Global Health Sector Strategy on HIV for 2016-2021. It establishes 15 ambitious targets, including the '90-90-90' target calling on health systems to reduce under-diagnosis of HIV, treat a greater number of those diagnosed......, and ensure that those being treated achieve viral suppression. DISCUSSION: The WHO strategy calls for person-centered chronic care for people living with HIV (PLHIV), implicitly acknowledging that viral suppression is not the ultimate goal of treatment. However, it stops short of providing an explicit target...... for health-related quality of life. It thus fails to take into account the needs of PLHIV who have achieved viral suppression but still must contend with other intense challenges such as serious non-communicable diseases, depression, anxiety, financial stress, and experiences of or apprehension about HIV...

Evolution of approaches to viral safety issues for biological products.

Science.gov (United States)

Lubiniecki, Anthony S

2011-01-01

CONFERENCE PROCEEDING Proceedings of the PDA/FDA Adventitious Viruses in Biologics: Detection and Mitigation Strategies Workshop in Bethesda, MD, USA; December 1-3, 2010 Guest Editors: Arifa Khan (Bethesda, MD), Patricia Hughes (Bethesda, MD) and Michael Wiebe (San Francisco, CA) Approaches to viral safety issues for biological products have evolved during the past 50+ years. The first cell culture products (viral vaccines) relied largely on the use of in vitro and in vivo virus screening assays that were based upon infectivity of adventitious viral agents. The use of Cohn fractionation and pasteurization by manufacturers of plasma derivatives introduced the concepts that purification and treatment with physical and chemical agents could greatly reduce the risk of viral contamination of human albumin and immunoglobulin products. But the limitations of such approaches became clear for thermolabile products that were removed early in fractionation such as antihemophilic factors, which transmitted hepatitis viruses and HIV-1 to some product recipients. These successes and limitations were taken into account by the early developers of recombinant DNA (rDNA)-derived cell culture products and by regulatory agencies, leading to the utilization of cloning technology to reduce/eliminate contamination due to human viruses and purification technologies to physically remove and inactivate adventitious and endogenous viruses, along with cell banking and cell bank characterization for adventitious and endogenous viruses, viral screening of biological raw materials, and testing of cell culture harvests, to ensure virus safety. Later development and incorporation of nanofiltration technology in the manufacturing process provided additional assurance of viral clearance for safety of biotechnology products. These measures have proven very effective at preventing iatrogenic infection of recipients of biotechnology products; however, viral contamination of production cell cultures has

Nucleocapsid-Independent Specific Viral RNA Packaging via Viral Envelope Protein and Viral RNA Signal

OpenAIRE

Narayanan, Krishna; Chen, Chun-Jen; Maeda, Junko; Makino, Shinji

2003-01-01

For any of the enveloped RNA viruses studied to date, recognition of a specific RNA packaging signal by the virus's nucleocapsid (N) protein is the first step described in the process of viral RNA packaging. In the murine coronavirus a selective interaction between the viral transmembrane envelope protein M and the viral ribonucleoprotein complex, composed of N protein and viral RNA containing a short cis-acting RNA element, the packaging signal, determines the selective RNA packaging into vi...

Contagious Content: Viral Video Ads Identification of Content Characteristics that Help Online Video Advertisements Go Viral

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Yentl Knossenburg

2016-12-01

Full Text Available Why do some online video advertisements go viral while others remain unnoticed? What kind of video content keeps the viewer interested and motivated to share? Many companies have realized the need to innovate their marketing strategies and have embraced the newest ways of using technology, as the Internet, to their advantage as in the example of virality. Yet few marketers actually understand how, and academic literature on this topic is still in development. This study investigated which content characteristics distinguish successful from non-successful online viral video advertisements by analyzing 641 cases using Structural Equation Modeling. Results show that Engagement and Surprise are two main content characteristics that significantly increase the chance of online video advertisements to go viral.  

Substance P Receptor Antagonism: A Potential Novel Treatment Option for Viral-Myocarditis

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Prema Robinson

2015-01-01

Full Text Available Viral-myocarditis is an important cause of heart failure for which no specific treatment is available. We previously showed the neuropeptide substance P (SP is associated with the pathogenesis of murine myocarditis caused by encephalomyocarditis virus (EMCV. The current studies determined if pharmacological inhibition of SP-signaling via its high affinity receptor, NK1R and downstream G-protein, Ras homolog gene family, member-A (RhoA, will be beneficial in viral-myocarditis. Aprepitant (1.2 mg/kg, a SP-receptor antagonist, or fasudil (10 mg/kg, a RhoA inhibitor, or saline control was administered daily to mice orally for 3 days, prior to, or 5 days following, intraperitoneal infection with and without 50 PFU of EMCV, following which disease assessment studies, including echocardiogram and cardiac Doppler were performed in day 14 after infection. Pretreatment and posttreatment with aprepitant significantly reduced mortality, heart and cardiomyocyte size, and cardiac viral RNA levels (P<0.05 all, ANOVA. Only aprepitant pretreatment improved heart functions; it significantly decreased end systolic diameter, improved fractional shortening, and increased peak aortic flow velocity (P<0.05 all, ANOVA. Pre- or posttreatment with fasudil did not significantly impact disease manifestations. These findings indicate that SP contributes to cardiac-remodeling and dysfunction following ECMV infection via its high affinity receptor, but not through the Rho-A pathway. These studies suggest that SP-receptor antagonism may be a novel therapeutic-option for patients with viral-myocarditis.

Viral Hepatitis

Science.gov (United States)

... Home A-Z Health Topics Viral hepatitis Viral hepatitis > A-Z Health Topics Viral hepatitis (PDF, 90 ... liver. Source: National Cancer Institute Learn more about hepatitis Watch a video. Learn who is at risk ...

Pharmacologic inhibition of COX-1 and COX-2 in influenza A viral infection in mice.

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Michelle A Carey

Full Text Available BACKGROUND: We previously demonstrated that cyclooxygenase (COX-1 deficiency results in greater morbidity and inflammation, whereas COX-2 deficiency leads to reduced morbidity, inflammation and mortality in influenza infected mice. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the effects of COX-1 and COX-2 inhibitors in influenza A viral infection. Mice were given a COX-1 inhibitor (SC-560, a COX-2 inhibitor (celecoxib or no inhibitor beginning 2 weeks prior to influenza A viral infection (200 PFU and throughout the course of the experiment. Body weight and temperature were measured daily as indicators of morbidity. Animals were sacrificed on days 1 and 4 post-infection and bronchoalveolar lavage (BAL fluid was collected or daily mortality was recorded up to 2 weeks post-infection. Treatment with SC-560 significantly increased mortality and was associated with profound hypothermia and greater weight loss compared to celecoxib or control groups. On day 4 of infection, BAL fluid cells were modestly elevated in celecoxib treated mice compared to SC-560 or control groups. Viral titres were similar between treatment groups. Levels of TNF-alpha and G-CSF were significantly attenuated in the SC-560 and celecoxib groups versus control and IL-6 levels were significantly lower in BAL fluid of celecoxib treated mice versus control and versus the SC-560 group. The chemokine KC was significantly lower in SC-560 group versus control. CONCLUSIONS/SIGNIFICANCE: Treatment with a COX-1 inhibitor during influenza A viral infection is detrimental to the host whereas inhibition of COX-2 does not significantly modulate disease severity. COX-1 plays a critical role in controlling the thermoregulatory response to influenza A viral infection in mice.

pUL34 binding near the human cytomegalovirus origin of lytic replication enhances DNA replication and viral growth.

Science.gov (United States)

Slayton, Mark; Hossain, Tanvir; Biegalke, Bonita J

2018-05-01

The human cytomegalovirus (HCMV) UL34 gene encodes sequence-specific DNA-binding proteins (pUL34) which are required for viral replication. Interactions of pUL34 with DNA binding sites represses transcription of two viral immune evasion genes, US3 and US9. 12 additional predicted pUL34-binding sites are present in the HCMV genome (strain AD169) with three binding sites concentrated near the HCMV origin of lytic replication (oriLyt). We used ChIP-seq analysis of pUL34-DNA interactions to confirm that pUL34 binds to the oriLyt region during infection. Mutagenesis of the UL34-binding sites in an oriLyt-containing plasmid significantly reduced viral-mediated oriLyt-dependent DNA replication. Mutagenesis of these sites in the HCMV genome reduced the replication efficiencies of the resulting viruses. Protein-protein interaction analyses demonstrated that pUL34 interacts with the viral proteins IE2, UL44, and UL84, that are essential for viral DNA replication, suggesting that pUL34-DNA interactions in the oriLyt region are involved in the DNA replication cascade. Copyright © 2018 Elsevier Inc. All rights reserved.

Viral replication in excised fin tissues (VREFT) corresponds with prior exposure of Pacific herring, Clupea pallasii (Valenciennes), to viral haemorrhagic septicaemia virus (VHSV)

Science.gov (United States)

Grady, C.A.; Gregg, J.L.; Wade, R.M.; Winton, J.R.; Hershberger, P.K.

2011-01-01

Procedures for a viral replication in excised fin tissue (VREFT) assay were adapted to Pacific herring, Clupea pallasii, and optimized both to reduce processing time and to provide the greatest resolution between na??ve herring and those previously exposed to viral haemorrhagic septicaemia virus (VHSV), Genogroup IVa. The optimized procedures included removal of the left pectoral fin from a euthanized fish, inoculation of the fin with >105 plaque-forming units (PFU) mL-1 VHSV for 1 h, rinsing the fin in fresh medium six times to remove unadsorbed virions, incubation of the fin in fresh medium for 4 days and enumeration of the viral titre in a sample of the incubation medium by plaque assay. The optimized VREFT assay was effective at identifying the prior exposure history of laboratory-reared Pacific herring to VHSV. The geometric mean VREFT value was significantly greater (P < 0.01) among na??ve herring (1.2 ?? 103 PFU mL-1) than among groups that survived exposure to VHSV (1.0-2.9 ?? 102 PFU mL-1); additionally, the proportion of cultures with no detectable virus was significantly greater (P = 0.0002) among fish that survived exposure to VHSV (39-47%) than among na??ve fish (3.3%). The optimized VREFT assay demonstrates promise for identifying VHSV exposure history and forecasting disease potential in populations of wild Pacific herring. ?? 2010 Blackwell Publishing Ltd.

Acute Pancreatitis in acute viral hepatitis

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S K.C.

2011-03-01

Full Text Available Introduction: The association of acute viral hepatitis and acute pancreatitis is well described. This study was conducted to find out the frequency of pancreatic involvement in acute viral hepatitis in the Nepalese population. Methods: Consecutive patients of acute viral hepatitis presenting with severe abdominal pain between January 2005 and April 2010 were studied. Patients with history of significant alcohol consumption and gall stones were excluded. Acute viral hepatitis was diagnosed by clinical examination, liver function test, ultrasound examination and confirmed by viral serology. Pancreatitis was diagnosed by clinical presentation, biochemistry, ultrasound examination and CT scan. Results: Severe abdominal pain was present in 38 of 382 serologically-confirmed acute viral hepatitis patients. Twenty five patients were diagnosed to have acute pancreatitis. The pancreatitis was mild in 14 and severe in 11 patients. The etiology of pancreatitis was hepatitis E virus in 18 and hepatitis A virus in 7 patients. Two patients died of complications secondary to shock. The remaining patients recovered from both pancreatitis and hepatitis on conservative treatment. Conclusions: Acute pancreatitis occurred in 6.5 % of patients with acute viral hepatitis. Cholelithiasis and gastric ulcers are the other causes of severe abdominal pain. The majority of the patients recover with conservative management. Keywords: acute viral hepatitis, acute pancreatitis, pain abdomen, hepatitis E, hepatitis A, endemic zone

Inhibition of Poliovirus-Induced Cleavage of Cellular Protein PCBP2 Reduces the Levels of Viral RNA Replication

Science.gov (United States)

Chase, Amanda J.; Daijogo, Sarah

2014-01-01

ABSTRACT Due to their small genome size, picornaviruses must utilize host proteins to mediate cap-independent translation and viral RNA replication. The host RNA-binding protein poly(rC) binding protein 2 (PCBP2) is involved in both processes in poliovirus infected cells. It has been shown that the viral proteinase 3CD cleaves PCBP2 and contributes to viral translation inhibition. However, cleaved PCBP2 remains active in viral RNA replication. This would suggest that both cleaved and intact forms of PCBP2 have a role in the viral RNA replication cycle. The picornavirus genome must act as a template for both translation and RNA replication. However, a template that is actively being translated cannot function as a template for RNA replication, suggesting that there is a switch in template usage from translation to RNA replication. We demonstrate that the cleavage of PCBP2 by the poliovirus 3CD proteinase is a necessary step for efficient viral RNA replication and, as such, may be important for mediating a switch in template usage from translation to RNA replication. IMPORTANCE Poliovirus, like all positive-strand RNA viruses that replicate in the cytoplasm of eukaryotic cells, uses its genomic RNA as a template for both viral protein synthesis and RNA replication. Given that these processes cannot occur simultaneously on the same template, poliovirus has evolved a mechanism(s) to facilitate the switch from using templates for translation to using them for RNA synthesis. This study explores one possible scenario for how the virus alters the functions of a host cell RNA binding protein to mediate, in part, this important transition. PMID:24371074

Molecular imaging of oncolytic viral therapy

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Dana Haddad

2014-01-01

Full Text Available Oncolytic viruses have made their mark on the cancer world as a potential therapeutic option, with the possible advantages of reduced side effects and strengthened treatment efficacy due to higher tumor selectivity. Results have been so promising, that oncolytic viral treatments have now been approved for clinical trials in several countries. However, clinical studies may benefit from the ability to noninvasively and serially identify sites of viral targeting via molecular imaging in order to provide safety, efficacy, and toxicity information. Furthermore, molecular imaging of oncolytic viral therapy may provide a more sensitive and specific diagnostic technique to detect tumor origin and, more importantly, presence of metastases. Several strategies have been investigated for molecular imaging of viral replication broadly categorized into optical and deep tissue imaging, utilizing several reporter genes encoding for fluorescence proteins, conditional enzymes, and membrane protein and transporters. Various imaging methods facilitate molecular imaging, including computer tomography, magnetic resonance imaging, positron emission tomography, single photon emission CT, gamma-scintigraphy, and photoacoustic imaging. In addition, several molecular probes are used for medical imaging, which act as targeting moieties or signaling agents. This review will explore the preclinical and clinical use of in vivo molecular imaging of replication-competent oncolytic viral therapy.

CRISPR/Cas9-mediated viral interference in plants

KAUST Repository

Ali, Zahir

2015-11-11

Background The CRISPR/Cas9 system provides bacteria and archaea with molecular immunity against invading phages and conjugative plasmids. Recently, CRISPR/Cas9 has been used for targeted genome editing in diverse eukaryotic species. Results In this study, we investigate whether the CRISPR/Cas9 system could be used in plants to confer molecular immunity against DNA viruses. We deliver sgRNAs specific for coding and non-coding sequences of tomato yellow leaf curl virus (TYLCV) into Nicotiana benthamiana plants stably overexpressing the Cas9 endonuclease, and subsequently challenge these plants with TYLCV. Our data demonstrate that the CRISPR/Cas9 system targeted TYLCV for degradation and introduced mutations at the target sequences. All tested sgRNAs exhibit interference activity, but those targeting the stem-loop sequence within the TYLCV origin of replication in the intergenic region (IR) are the most effective. N. benthamiana plants expressing CRISPR/Cas9 exhibit delayed or reduced accumulation of viral DNA, abolishing or significantly attenuating symptoms of infection. Moreover, this system could simultaneously target multiple DNA viruses. Conclusions These data establish the efficacy of the CRISPR/Cas9 system for viral interference in plants, thereby extending the utility of this technology and opening the possibility of producing plants resistant to multiple viral infections.

The effect of churn on "community viral load" in a well-defined regional population.

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Krentz, Hartmut B; Gill, M John

2013-10-01

The concept of community viral load (CVL) was introduced to quantify the pool of transmissible HIV within a community and to monitor the potential impact of highly active antiretroviral therapy (HAART) on reducing new infections. The implications of churn (patient movement in/out of care in a community) on CVL have not been studied. The annual CVL was determined in the entire geographic HIV population receiving care in southern Alberta from 2001 to 2010; the CVL for specific subpopulations was analyzed for 2009. CVL was determined for patients under continuous care, newly diagnosed, new to the region, moved away, returned, and lost to follow-up (LTFU). Viral loads (VLs) churn significantly limited CVL use as a measure for evaluating the impact of HAART in reducing HIV transmissions in our population.

Glycolytic control of vacuolar-type ATPase activity: A mechanism to regulate influenza viral infection

Energy Technology Data Exchange (ETDEWEB)

Kohio, Hinissan P.; Adamson, Amy L., E-mail: aladamso@uncg.edu

2013-09-15

As new influenza virus strains emerge, finding new mechanisms to control infection is imperative. In this study, we found that we could control influenza infection of mammalian cells by altering the level of glucose given to cells. Higher glucose concentrations induced a dose-specific increase in influenza infection. Linking influenza virus infection with glycolysis, we found that viral replication was significantly reduced after cells were treated with glycolytic inhibitors. Addition of extracellular ATP after glycolytic inhibition restored influenza infection. We also determined that higher levels of glucose promoted the assembly of the vacuolar-type ATPase within cells, and increased vacuolar-type ATPase proton-transport activity. The increase of viral infection via high glucose levels could be reversed by inhibition of the proton pump, linking glucose metabolism, vacuolar-type ATPase activity, and influenza viral infection. Taken together, we propose that altering glucose metabolism may be a potential new approach to inhibit influenza viral infection. - Highlights: • Increased glucose levels increase Influenza A viral infection of MDCK cells. • Inhibition of the glycolytic enzyme hexokinase inhibited Influenza A viral infection. • Inhibition of hexokinase induced disassembly the V-ATPase. • Disassembly of the V-ATPase and Influenza A infection was bypassed with ATP. • The state of V-ATPase assembly correlated with Influenza A infection of cells.

Glycolytic control of vacuolar-type ATPase activity: A mechanism to regulate influenza viral infection

International Nuclear Information System (INIS)

Kohio, Hinissan P.; Adamson, Amy L.

2013-01-01

As new influenza virus strains emerge, finding new mechanisms to control infection is imperative. In this study, we found that we could control influenza infection of mammalian cells by altering the level of glucose given to cells. Higher glucose concentrations induced a dose-specific increase in influenza infection. Linking influenza virus infection with glycolysis, we found that viral replication was significantly reduced after cells were treated with glycolytic inhibitors. Addition of extracellular ATP after glycolytic inhibition restored influenza infection. We also determined that higher levels of glucose promoted the assembly of the vacuolar-type ATPase within cells, and increased vacuolar-type ATPase proton-transport activity. The increase of viral infection via high glucose levels could be reversed by inhibition of the proton pump, linking glucose metabolism, vacuolar-type ATPase activity, and influenza viral infection. Taken together, we propose that altering glucose metabolism may be a potential new approach to inhibit influenza viral infection. - Highlights: • Increased glucose levels increase Influenza A viral infection of MDCK cells. • Inhibition of the glycolytic enzyme hexokinase inhibited Influenza A viral infection. • Inhibition of hexokinase induced disassembly the V-ATPase. • Disassembly of the V-ATPase and Influenza A infection was bypassed with ATP. • The state of V-ATPase assembly correlated with Influenza A infection of cells

Experimentally-induced immune activation in natural hosts of SIV induces significant increases in viral replication and CD4+ T cell depletion

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Ribeiro, Ruy M [Los Alamos National Laboratory

2008-01-01

Chronically SIVagm-infected African green monkeys (AGMs) have a remarkably stable non-pathogenic disease course, with levels of immune activation in chronic SIVagm infection similar to those observed in uninfected monkeys and stable viral loads (VLs) for long periods of time. In vivo administration of lipopolysaccharide (LPS) or an IL-2/diphtheria toxin fusion protein (Ontak) to chronically SIVagm-infected AGMs triggered increases in immune activation and subsequently of viral replication and depletion of intestinal CD4{sup +} T cells. Our study indicates that circulating microbial products can increase viral replication by inducing immune activation and increasing the number of viral target cells, thus demonstrating that immune activation and T cell prolifeation are key factors in AIDS pathogenesis.

101 . experience with hepatitis b viral load testing in nigeria

African Journals Online (AJOL)

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ABSTRACT. Background: Quantification of the viral burden is an important laboratory tool in the management of hepatitis B virus. (HBV)-infected patients. However, widespread use of assays is still hampered by the high cost. Treatment reduces viral load to undetectable levels. HBV infected patients tend to have high HBV ...

Proteasome inhibitors induce apoptosis and reduce viral replication in primary effusion lymphoma cells

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Saji, Chiaki [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812 (Japan); Higashi, Chizuka; Niinaka, Yasufumi [Faculty of Medicine, University of Yamanashi, Chuoh-shi 409-3898 (Japan); Yamada, Koji [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812 (Japan); Noguchi, Kohji [Faculty of Pharmacy, Keio University, 1-5-30 Shiba-koen, Minato-ku, Tokyo 105-8512 (Japan); Fujimuro, Masahiro, E-mail: fuji2@mb.kyoto-phu.ac.jp [Department of Cell Biology, Kyoto Pharmaceutical University, Misasagi-Shichonocho 1, Yamashinaku, Kyoto 607-8412 (Japan)

2011-12-02

Highlights: Black-Right-Pointing-Pointer Constitutive NF-{kappa}B signaling is essential for the survival and growth of PEL cells. Black-Right-Pointing-Pointer NF-{kappa}B signaling is upregulated by the proteasome-dependent degradation of I{kappa}B{alpha}. Black-Right-Pointing-Pointer Proteasome inhibitors suppress NF-{kappa}B signaling and induce apoptosis in PEL cells through stabilization of I{kappa}B{alpha}. Black-Right-Pointing-Pointer Proteasome inhibitors suppress viral replication in PEL cells during lytic KSHV infection. -- Abstract: Primary effusion lymphoma (PEL) is an aggressive neoplasm caused by Kaposi's sarcoma-associated herpesvirus (KSHV). This study provides evidence that proteasomal activity is required for both survival of PEL cells stably harboring the KSHV genome and viral replication of KSHV. We evaluated the cytotoxic effects of proteasome inhibitors on PEL cells. The proteasome inhibitors MG132, lactacystin, and proteasome inhibitor I dramatically inhibited cell proliferation and induced apoptosis of PEL cells through the accumulation of p21 and p27. Furthermore, proteasome inhibitors induced the stabilization of NF-{kappa}B inhibitory molecule (I{kappa}B{alpha}) and suppressed the transcriptional activity of NF-{kappa}B in PEL cells. The NF-{kappa}B specific inhibitor BAY11-7082 also induced apoptosis in PEL cells. The constitutive activation of NF-{kappa}B signaling is essential for the survival and growth of B cell lymphoma cells, including PEL cells. NF-{kappa}B signaling is upregulated by proteasome-dependent degradation of I{kappa}B{alpha}. The suppression of NF-{kappa}B signaling by proteasome inhibitors may contribute to the induction of apoptosis in PEL cells. In addition, proteasome activity is required for KSHV replication in KSHV latently infected PEL cells. MG132 reduced the production of progeny virus from PEL cells at low concentrations, which do not affect PEL cell growth. These findings suggest that proteasome

Experience with Hepatitis B viral load testing in Nigeria | Okwuraiwe ...

African Journals Online (AJOL)

Background: Quantification of the viral burden is an important laboratory tool in the management of hepatitis B virus (HBV)-infected patients. However, widespread use of assays is still hampered by the high cost. Treatment reduces viral load to undetectable levels. HBV infected patients tend to have high HBV DNA levels, ...

Potyviral VPg enhances viral RNA Translation and inhibits reporter mRNA translation in planta.

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Eskelin, Katri; Hafrén, Anders; Rantalainen, Kimmo I; Mäkinen, Kristiina

2011-09-01

Viral protein genome-linked (VPg) plays a central role in several stages of potyvirus infection. This study sought to answer questions about the role of Potato virus A (PVA; genus Potyvirus) VPg in viral and host RNA expression. When expressed in Nicotiana benthamiana leaves in trans, a dual role of VPg in translation is observed. It repressed the expression of monocistronic luciferase (luc) mRNA and simultaneously induced a significant upregulation in the expression of both replicating and nonreplicating PVA RNAs. This enhanced viral gene expression was due at least to the 5' untranslated region (UTR) of PVA RNA, eukaryotic initiation factors 4E and iso 4E [eIF4E/eIF(iso)4E], and the presence of a sufficient amount of VPg. Coexpression of VPg with viral RNA increased the viral RNA amount, which was not the case with the monocistronic mRNA. Both mutations at certain lysine residues in PVA VPg and eIF4E/eIF(iso)4E depletion reduced its ability to upregulate the viral RNA expression. These modifications were also involved in VPg-mediated downregulation of monocistronic luc expression. These results suggest that VPg can titrate eIF4Es from capped monocistronic RNAs. Because VPg-mediated enhancement of viral gene expression required eIF4Es, it is possible that VPg directs eIF4Es to promote viral RNA expression. From this study it is evident that VPg can serve as a specific regulator of PVA expression by boosting the viral RNA amounts as well as the accumulation of viral translation products. Such a mechanism could function to protect viral RNA from being degraded and to secure efficient production of coat protein (CP) for virion formation.

Potyviral VPg Enhances Viral RNA Translation and Inhibits Reporter mRNA Translation In Planta▿

Science.gov (United States)

Eskelin, Katri; Hafrén, Anders; Rantalainen, Kimmo I.; Mäkinen, Kristiina

2011-01-01

Viral protein genome-linked (VPg) plays a central role in several stages of potyvirus infection. This study sought to answer questions about the role of Potato virus A (PVA; genus Potyvirus) VPg in viral and host RNA expression. When expressed in Nicotiana benthamiana leaves in trans, a dual role of VPg in translation is observed. It repressed the expression of monocistronic luciferase (luc) mRNA and simultaneously induced a significant upregulation in the expression of both replicating and nonreplicating PVA RNAs. This enhanced viral gene expression was due at least to the 5′ untranslated region (UTR) of PVA RNA, eukaryotic initiation factors 4E and iso 4E [eIF4E/eIF(iso)4E], and the presence of a sufficient amount of VPg. Coexpression of VPg with viral RNA increased the viral RNA amount, which was not the case with the monocistronic mRNA. Both mutations at certain lysine residues in PVA VPg and eIF4E/eIF(iso)4E depletion reduced its ability to upregulate the viral RNA expression. These modifications were also involved in VPg-mediated downregulation of monocistronic luc expression. These results suggest that VPg can titrate eIF4Es from capped monocistronic RNAs. Because VPg-mediated enhancement of viral gene expression required eIF4Es, it is possible that VPg directs eIF4Es to promote viral RNA expression. From this study it is evident that VPg can serve as a specific regulator of PVA expression by boosting the viral RNA amounts as well as the accumulation of viral translation products. Such a mechanism could function to protect viral RNA from being degraded and to secure efficient production of coat protein (CP) for virion formation. PMID:21697470

PAR-1 contributes to the innate immune response during viral infection

Science.gov (United States)

Antoniak, Silvio; Owens, A. Phillip; Baunacke, Martin; Williams, Julie C.; Lee, Rebecca D.; Weithäuser, Alice; Sheridan, Patricia A.; Malz, Ronny; Luyendyk, James P.; Esserman, Denise A.; Trejo, JoAnn; Kirchhofer, Daniel; Blaxall, Burns C.; Pawlinski, Rafal; Beck, Melinda A.; Rauch, Ursula; Mackman, Nigel

2013-01-01

Coagulation is a host defense system that limits the spread of pathogens. Coagulation proteases, such as thrombin, also activate cells by cleaving PARs. In this study, we analyzed the role of PAR-1 in coxsackievirus B3–induced (CVB3-induced) myocarditis and influenza A infection. CVB3-infected Par1–/– mice expressed reduced levels of IFN-β and CXCL10 during the early phase of infection compared with Par1+/+ mice that resulted in higher viral loads and cardiac injury at day 8 after infection. Inhibition of either tissue factor or thrombin in WT mice also significantly increased CVB3 levels in the heart and cardiac injury compared with controls. BM transplantation experiments demonstrated that PAR-1 in nonhematopoietic cells protected mice from CVB3 infection. Transgenic mice overexpressing PAR-1 in cardiomyocytes had reduced CVB3-induced myocarditis. We found that cooperative signaling between PAR-1 and TLR3 in mouse cardiac fibroblasts enhanced activation of p38 and induction of IFN-β and CXCL10 expression. Par1–/– mice also had decreased CXCL10 expression and increased viral levels in the lung after influenza A infection compared with Par1+/+ mice. Our results indicate that the tissue factor/thrombin/PAR-1 pathway enhances IFN-β expression and contributes to the innate immune response during single-stranded RNA viral infection. PMID:23391721

Seroprevalence of viral and bacterial diseases among the bovines in Himachal Pradesh, India

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Shailja Katoch

2017-12-01

Full Text Available Aim: The study was designed to measure the seroprevalence of viral and bacterial diseases: Infectious bovine rhinotracheitis, bovine viral diarrhea, bovine leukemia, bovine parainfluenza, bovine respiratory syncytial disease, brucellosis, and paratuberculosis among bovine of Himachal Pradesh during the year 2013-2015. Materials and Methods: The serum samples were collected from seven districts of state, namely, Bilaspur, Kangra, Kinnaur, Lahul and Spiti, Mandi, Sirmour, and Solan. The samples were screened using indirect ELISA kits to measure the seroprevalence of viral and bacterial diseases. Results: The overall seroprevalence of infectious bovine rhinotracheitis was 24.24%, bovine viral diarrhea 1.52%, bovine leukemia 9.09%, bovine parainfluenza 57.58%, bovine respiratory syncytial disease 50%, brucellosis 19.69%, and paratuberculosis 9.09% in Himachal Pradesh. The seroprevalence of bovine rhinotracheitis, bovine leukemia, bovine parainfluenza, bovine respiratory syncytial disease, and paratuberculosis in the state varied significantly (p0.01. Multiple seropositivity has been observed in this study. Bovine parainfluenza virus 3 was observed commonly in mixed infection with almost all viruses and bacteria under study. Conclusion: The viral and bacterial diseases are prevalent in the seven districts of Himachal Pradesh investigated in the study. Therefore, appropriate management practices and routine vaccination programs should be adopted to reduce the prevalence of these diseases.

Recent Advances in Non-viral Vectors for Gene Delivery

Science.gov (United States)

Guo, Xia; Huang, Leaf

2011-01-01

CONSPECTUS Non-viral vectors, typically based on cationic lipids or polymers, are preferred due to safety concerns with viral vectors. So far, non-viral vectors can proficiently transfect cells in culture, but obtaining efficient nanomedicines is far from evident. To overcome the hurdles associated with non-viral vectors is significant for improving delivery efficiency and therapeutic effect of nucleic acid. The drawbacks include the strong interaction of cationic delivery vehicles with blood components, uptake by the reticuloendothelial system (RES), toxicity, targeting ability of the carriers to the cells of interest, and so on. PEGylation is the predominant method used to reduce the binding of plasma proteins with non-viral vectors and minimize the clearance by RES after intravenous administration. The nanoparticles that are not rapidly cleared from the circulation accumulate in the tumors due to the enhanced permeability and retention effect, and the targeting ligands attached to the distal end of the PEGylated components allow binding to the receptors on the target cell surface. Neutral or anionic liposomes have been also developed for systemic delivery of nucleic acids in experimental animal model. Designing and synthesizing novel cationic lipids and polymers, and binding nucleic acid with peptides, targeting ligands, polymers, or environmentally sensitive moieties also attract many attentions for resolving the problems encountered by non-viral vectors. The application of inorganic nanoparticles in nucleic acid delivery is an emerging field, too. Recently, different classes of non-viral vectors appear to be converging and the features of different classes of non-viral vectors could be combined in one strategy. More hurdles associated with efficient nucleic acid delivery therefore might be expected to be overcome. In this account, we will focus on these novel non-viral vectors, which are classified into multifunctional hybrid nucleic acid vectors, novel

Nordihydroguaiaretic acid (NDGA) inhibits replication and viral morphogenesis of dengue virus.

Science.gov (United States)

Soto-Acosta, Rubén; Bautista-Carbajal, Patricia; Syed, Gulam H; Siddiqui, Aleem; Del Angel, Rosa M

2014-09-01

Dengue is the most common mosquito borne viral disease in humans. The infection with any of the 4 dengue virus serotypes (DENV) can either be asymptomatic or manifest in two clinical forms, the mild dengue fever or the more severe dengue hemorrhagic fever that may progress into dengue shock syndrome. A DENV replicative cycle relies on host lipid metabolism; specifically, DENV infection modulates cholesterol and fatty acid synthesis, generating a lipid-enriched cellular environment necessary for viral replication. Thus, the aim of this work was to evaluate the anti-DENV effect of the Nordihydroguaiaretic acid (NDGA), a hypolipidemic agent with antioxidant and anti-inflammatory properties. A dose-dependent inhibition in viral yield and NS1 secretion was observed in supernatants of infected cells treated for 24 and 48 h with different concentrations of NDGA. To evaluate the effect of NDGA in DENV replication, a DENV4 replicon transfected Vero cells were treated with different concentrations of NDGA. NDGA treatment significantly reduced DENV replication, reiterating the importance of lipids in viral replication. NDGA treatment also led to reduction in number of lipid droplets (LDs), the neutral lipid storage organelles involved in DENV morphogenesis that are known to increase in number during DENV infection. Furthermore, NDGA treatment resulted in dissociation of the C protein from LDs. Overall our results suggest that NDGA inhibits DENV infection by targeting genome replication and viral assembly. Copyright © 2014 Elsevier B.V. All rights reserved.

The proteasomal Rpn11 metalloprotease suppresses tombusvirus RNA recombination and promotes viral replication via facilitating assembly of the viral replicase complex.

Science.gov (United States)

Prasanth, K Reddisiva; Barajas, Daniel; Nagy, Peter D

2015-03-01

RNA viruses co-opt a large number of cellular proteins that affect virus replication and, in some cases, viral genetic recombination. RNA recombination helps viruses in an evolutionary arms race with the host's antiviral responses and adaptation of viruses to new hosts. Tombusviruses and a yeast model host are used to identify cellular factors affecting RNA virus replication and RNA recombination. In this study, we have examined the role of the conserved Rpn11p metalloprotease subunit of the proteasome, which couples deubiquitination and degradation of proteasome substrates, in tombusvirus replication and recombination in Saccharomyces cerevisiae and plants. Depletion or mutations of Rpn11p lead to the rapid formation of viral RNA recombinants in combination with reduced levels of viral RNA replication in yeast or in vitro based on cell extracts. Rpn11p interacts with the viral replication proteins and is recruited to the viral replicase complex (VRC). Analysis of the multifunctional Rpn11p has revealed that the primary role of Rpn11p is to act as a "matchmaker" that brings the viral p92(pol) replication protein and the DDX3-like Ded1p/RH20 DEAD box helicases into VRCs. Overexpression of Ded1p can complement the defect observed in rpn11 mutant yeast by reducing TBSV recombination. This suggests that Rpn11p can suppress tombusvirus recombination via facilitating the recruitment of the cellular Ded1p helicase, which is a strong suppressor of viral recombination, into VRCs. Overall, this work demonstrates that the co-opted Rpn11p, which is involved in the assembly of the functional proteasome, also functions in the proper assembly of the tombusvirus VRCs. RNA viruses evolve rapidly due to genetic changes based on mutations and RNA recombination. Viral genetic recombination helps viruses in an evolutionary arms race with the host's antiviral responses and facilitates adaptation of viruses to new hosts. Cellular factors affect viral RNA recombination, although the role

[Viral hepatitis in travellers].

Science.gov (United States)

Abreu, Cândida

2007-01-01

Considering the geographical asymmetric distribution of viral hepatitis A, B and E, having a much higher prevalence in the less developed world, travellers from developed countries are exposed to a considerable and often underestimated risk of hepatitis infection. In fact a significant percentage of viral hepatitis occurring in developed countries is travel related. This results from globalization and increased mobility from tourism, international work, humanitarian and religious missions or other travel related activities. Several studies published in Europe and North America shown that more than 50% of reported cases of hepatitis A are travel related. On the other hand frequent outbreaks of hepatitis A and E in specific geographic areas raise the risk of infection in these restricted zones and that should be clearly identified. Selected aspects related with the distribution of hepatitis A, B and E are reviewed, particularly the situation in Portugal according to the published studies, as well as relevant clinical manifestations and differential diagnosis of viral hepatitis. Basic prevention rules considering enteric transmitted hepatitis (hepatitis A and hepatitis E) and parenteral transmitted (hepatitis B) are reviewed as well as hepatitis A and B immunoprophylaxis. Common clinical situations and daily practice "pre travel" advice issues are discussed according to WHO/CDC recommendations and the Portuguese National Vaccination Program. Implications from near future availability of a hepatitis E vaccine, a currently in phase 2 trial, are highlighted. Potential indications for travellers to endemic countries like India, Nepal and some regions of China, where up to 30% of sporadic cases of acute viral hepatitis are caused by hepatitis E virus, are considered. Continued epidemiological surveillance for viral hepatitis is essential to recognize and control possible outbreaks, but also to identify new viral hepatitis agents that may emerge as important global health

Heat shock protein-90-beta facilitates enterovirus 71 viral particles assembly

International Nuclear Information System (INIS)

Wang, Robert Y.L.; Kuo, Rei-Lin; Ma, Wei-Chieh; Huang, Hsing-I; Yu, Jau-Song; Yen, Sih-Min; Huang, Chi-Ruei; Shih, Shin-Ru

2013-01-01

Molecular chaperones are reported to be crucial for virus propagation, but are not yet addressed in Human Enterovirus 71 (EV71). Here we describe the specific association of heat shock protein-90-beta (Hsp90β), but not alpha form (Hsp90α), with EV71 viral particles by the co-purification with virions using sucrose density gradient ultracentrifugation, and by the colocalization with viral particles, as assessed by immunogold electron microscopy. The reduction of the Hsp90β protein using RNA interference decreased the correct assembly of viral particles, without affecting EV71 replication levels. Tracking ectopically expressed Hsp90β protein associated with EV71 virions revealed that Hsp90β protein was transmitted to new host cells through its direct association with infectious viral particles. Our findings suggest a new antiviral strategy in which extracellular Hsp90β protein is targeted to decrease the infectivity of EV71 and other enteroviruses, without affecting the broader functions of this constitutively expressed molecular chaperone. - Highlights: • Hsp90β is associated with EV71 virion and is secreted with the release virus. • Hsp90β effects on the correct assembly of viral particles. • Viral titer of cultured medium was reduced in the presence of geldanamycin. • Viral titer was also reduced when Hsp90β was suppressed by siRNA treatment. • The extracellular Hsp90β was also observed in other RNA viruses-infected cells

Heat shock protein-90-beta facilitates enterovirus 71 viral particles assembly

Energy Technology Data Exchange (ETDEWEB)

Wang, Robert Y.L., E-mail: yuwang@mail.cgu.edu.tw [Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan (China); Department of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333 Taiwan (China); Kuo, Rei-Lin [Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan (China); Department of Medical Biotechnology and Laboratory Science and Graduate Program of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan (China); Ma, Wei-Chieh [Department of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333 Taiwan (China); Huang, Hsing-I [Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan (China); Department of Medical Biotechnology and Laboratory Science and Graduate Program of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan (China); Yu, Jau-Song [Department of Cell and Molecular Biology, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan (China); Molecular Medicine Research Center, Chang Gung University, Tao-Yuan 333, Taiwan (China); Yen, Sih-Min [Department of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333 Taiwan (China); Huang, Chi-Ruei [Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan (China); Department of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333 Taiwan (China); Shih, Shin-Ru [Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan (China); Department of Medical Biotechnology and Laboratory Science and Graduate Program of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan (China)

2013-09-01

Molecular chaperones are reported to be crucial for virus propagation, but are not yet addressed in Human Enterovirus 71 (EV71). Here we describe the specific association of heat shock protein-90-beta (Hsp90β), but not alpha form (Hsp90α), with EV71 viral particles by the co-purification with virions using sucrose density gradient ultracentrifugation, and by the colocalization with viral particles, as assessed by immunogold electron microscopy. The reduction of the Hsp90β protein using RNA interference decreased the correct assembly of viral particles, without affecting EV71 replication levels. Tracking ectopically expressed Hsp90β protein associated with EV71 virions revealed that Hsp90β protein was transmitted to new host cells through its direct association with infectious viral particles. Our findings suggest a new antiviral strategy in which extracellular Hsp90β protein is targeted to decrease the infectivity of EV71 and other enteroviruses, without affecting the broader functions of this constitutively expressed molecular chaperone. - Highlights: • Hsp90β is associated with EV71 virion and is secreted with the release virus. • Hsp90β effects on the correct assembly of viral particles. • Viral titer of cultured medium was reduced in the presence of geldanamycin. • Viral titer was also reduced when Hsp90β was suppressed by siRNA treatment. • The extracellular Hsp90β was also observed in other RNA viruses-infected cells.

A Loop Region in the N-Terminal Domain of Ebola Virus VP40 Is Important in Viral Assembly, Budding, and Egress

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Emmanuel Adu-Gyamfi

2014-10-01

Full Text Available Ebola virus (EBOV causes viral hemorrhagic fever in humans and can have clinical fatality rates of ~60%. The EBOV genome consists of negative sense RNA that encodes seven proteins including viral protein 40 (VP40. VP40 is the major Ebola virus matrix protein and regulates assembly and egress of infectious Ebola virus particles. It is well established that VP40 assembles on the inner leaflet of the plasma membrane of human cells to regulate viral budding where VP40 can produce virus like particles (VLPs without other Ebola virus proteins present. The mechanistic details, however, of VP40 lipid-interactions and protein-protein interactions that are important for viral release remain to be elucidated. Here, we mutated a loop region in the N-terminal domain of VP40 (Lys127, Thr129, and Asn130 and find that mutations (K127A, T129A, and N130A in this loop region reduce plasma membrane localization of VP40. Additionally, using total internal reflection fluorescence microscopy and number and brightness analysis we demonstrate these mutations greatly reduce VP40 oligomerization. Lastly, VLP assays demonstrate these mutations significantly reduce VLP release from cells. Taken together, these studies identify an important loop region in VP40 that may be essential to viral egress.

Independent predictive factors for significant liver histological changes in patients with HBeAg-positive high-viral-load chronic HBV infection and a normal alanine aminotransferase level

Directory of Open Access Journals (Sweden)

LI Qiang

2016-07-01

Full Text Available Objective To investigate the independent predictive factors for significant liver histological changes (SLHCs in patients with HBeAg-positive high-viral-load chronic hepatitis B virus (HBV infection and a normal alanine aminotransferase (ALT level. MethodsA retrospective analysis was performed on the clinical data of 116 previously untreated patients with HBeAg-positive high-viral-load (HBV DNA≥105 copies/ml chronic HBV infection and a normal ALT level (＜50 U/L who were hospitalized in Shanghai Public Health Clinical Center Affiliated to Fudan University from June 2013 to August 2015. The definition of SLHCs was inflammation ≥G2 and/or fibrosis≥S2. The t-test or Mann-Whitney U rank sum test was used for comparison of continuous data between groups, and the chi-square test was used for comparison of categorical data between groups. Univariate and multivariate regression analyses were used to determine independent predictive factors for SLHCs. ResultsOf all the 116 patients, 47(40.5% had SLHCs. The multivariate analysis showed that age (OR=2.828, P＜0.05, ALT (OR=1.011, P＜0.05, and gamma-glutamyl transpeptidase (GGT (OR=1.089, P＜0.05 were independent predictors for SLHCs in patients with HBeAg-positive high-viral-load chronic HBV infection and a normal ALT level. The patients aged ≤30 years had a significantly lower incidence rate of SLHCs than those aged＞30 years (21.6% vs 49.4%, χ2=6.42, P=0.015, the patients with ALT ≤30 U/L had a significantly lower incidence rate of SLHCs than those with 30 U/L＜ALT≤50 U/L (17.6% vs 50.0%, χ2=19.86, P＜0.001, and the patients with GGT≤40 U/L had a significantly lower incidence rate of SLHCs than those with GGT＞40 U/L (28.8% vs 66.7%, χ2=28.63, P＜0.001. ConclusionIn patients with HBeAg-positive high-viral-load chronic HBV infection and a normal ALT level, those with an age of＞30 years, ALT＞30 U/L, and GGT＞40 U/L tend to develop SLHCs and need liver biopsy.

Pharyngitis - viral

Science.gov (United States)

... throat is due to a viral infection. The antibiotics will not help. Using them to treat viral infections helps bacteria become resistant to antibiotics. With some sore throats (such as those caused ...

Identification of a novel multiple kinase inhibitor with potent antiviral activity against influenza virus by reducing viral polymerase activity

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Yutaka; Kakisaka, Michinori; Chutiwitoonchai, Nopporn [Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Tajima, Shigeru [Department of Virology I, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku, Tokyo 162-8640 (Japan); Hikono, Hirokazu; Saito, Takehiko [Influenza and Prion Disease Research Center, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), 3-1-5 Kannondai, Tsukuba, Ibaraki 305-0856 (Japan); Aida, Yoko, E-mail: aida@riken.jp [Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

2014-07-18

Highlights: • Screening of 50,000 compounds and subsequent lead optimization identified WV970. • WV970 has antiviral effects against influenza A, B and highly pathogenic viral strains. • WV970 inhibits viral genome replication and transcription. • A target database search suggests that WV970 may bind to a number of kinases. • KINOMEscan screening revealed that WV970 has inhibitory effects on 15 kinases. - Abstract: Neuraminidase inhibitors are the only currently available influenza treatment, although resistant viruses to these drugs have already been reported. Thus, new antiviral drugs with novel mechanisms of action are urgently required. In this study, we identified a novel antiviral compound, WV970, through cell-based screening of a 50,000 compound library and subsequent lead optimization. This compound exhibited potent antiviral activity with nanomolar IC{sub 50} values against both influenza A and B viruses but not non-influenza RNA viruses. Time-of-addition and indirect immunofluorescence assays indicated that WV970 acted at an early stage of the influenza life cycle, but likely after nuclear entry of viral ribonucleoprotein (vRNP). Further analyses of viral RNA expression and viral polymerase activity indicated that WV970 inhibited vRNP-mediated viral genome replication and transcription. Finally, structure-based virtual screening and comprehensive human kinome screening were used to demonstrate that WV970 acts as a multiple kinase inhibitor, many of which are associated with influenza virus replication. Collectively, these results strongly suggest that WV970 is a promising anti-influenza drug candidate and that several kinases associated with viral replication are promising drug targets.

Identification of a novel multiple kinase inhibitor with potent antiviral activity against influenza virus by reducing viral polymerase activity

International Nuclear Information System (INIS)

Sasaki, Yutaka; Kakisaka, Michinori; Chutiwitoonchai, Nopporn; Tajima, Shigeru; Hikono, Hirokazu; Saito, Takehiko; Aida, Yoko

2014-01-01

Highlights: • Screening of 50,000 compounds and subsequent lead optimization identified WV970. • WV970 has antiviral effects against influenza A, B and highly pathogenic viral strains. • WV970 inhibits viral genome replication and transcription. • A target database search suggests that WV970 may bind to a number of kinases. • KINOMEscan screening revealed that WV970 has inhibitory effects on 15 kinases. - Abstract: Neuraminidase inhibitors are the only currently available influenza treatment, although resistant viruses to these drugs have already been reported. Thus, new antiviral drugs with novel mechanisms of action are urgently required. In this study, we identified a novel antiviral compound, WV970, through cell-based screening of a 50,000 compound library and subsequent lead optimization. This compound exhibited potent antiviral activity with nanomolar IC 50 values against both influenza A and B viruses but not non-influenza RNA viruses. Time-of-addition and indirect immunofluorescence assays indicated that WV970 acted at an early stage of the influenza life cycle, but likely after nuclear entry of viral ribonucleoprotein (vRNP). Further analyses of viral RNA expression and viral polymerase activity indicated that WV970 inhibited vRNP-mediated viral genome replication and transcription. Finally, structure-based virtual screening and comprehensive human kinome screening were used to demonstrate that WV970 acts as a multiple kinase inhibitor, many of which are associated with influenza virus replication. Collectively, these results strongly suggest that WV970 is a promising anti-influenza drug candidate and that several kinases associated with viral replication are promising drug targets

Mutations in matrix and SP1 repair the packaging specificity of a Human Immunodeficiency Virus Type 1 mutant by reducing the association of Gag with spliced viral RNA

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Ristic Natalia

2010-09-01

Full Text Available Abstract Background The viral genome of HIV-1 contains several secondary structures that are important for regulating viral replication. The stem-loop 1 (SL1 sequence in the 5' untranslated region directs HIV-1 genomic RNA dimerization and packaging into the virion. Without SL1, HIV-1 cannot replicate in human T cell lines. The replication restriction phenotype in the SL1 deletion mutant appears to be multifactorial, with defects in viral RNA dimerization and packaging in producer cells as well as in reverse transcription of the viral RNA in infected cells. In this study, we sought to characterize SL1 mutant replication restrictions and provide insights into the underlying mechanisms of compensation in revertants. Results HIV-1 lacking SL1 (NLΔSL1 did not replicate in PM-1 cells until two independent non-synonymous mutations emerged: G913A in the matrix domain (E42K on day 18 postinfection and C1907T in the SP1 domain (P10L on day 11 postinfection. NLΔSL1 revertants carrying either compensatory mutation showed enhanced infectivity in PM-1 cells. The SL1 revertants produced significantly more infectious particles per nanogram of p24 than did NLΔSL1. The SL1 deletion mutant packaged less HIV-1 genomic RNA and more cellular RNA, particularly signal recognition particle RNA, in the virion than the wild-type. NLΔSL1 also packaged 3- to 4-fold more spliced HIV mRNA into the virion, potentially interfering with infectious virus production. In contrast, both revertants encapsidated 2.5- to 5-fold less of these HIV-1 mRNA species. Quantitative RT-PCR analysis of RNA cross-linked with Gag in formaldehyde-fixed cells demonstrated that the compensatory mutations reduced the association between Gag and spliced HIV-1 RNA, thereby effectively preventing these RNAs from being packaged into the virion. The reduction of spliced viral RNA in the virion may have a major role in facilitating infectious virus production, thus restoring the infectivity of NLΔSL1

Pooled HIV-1 viral load testing using dried blood spots to reduce the cost of monitoring antiretroviral treatment in a resource-limited setting.

Science.gov (United States)

Pannus, Pieter; Fajardo, Emmanuel; Metcalf, Carol; Coulborn, Rebecca M; Durán, Laura T; Bygrave, Helen; Ellman, Tom; Garone, Daniela; Murowa, Michael; Mwenda, Reuben; Reid, Tony; Preiser, Wolfgang

2013-10-01

Rollout of routine HIV-1 viral load monitoring is hampered by high costs and logistical difficulties associated with sample collection and transport. New strategies are needed to overcome these constraints. Dried blood spots from finger pricks have been shown to be more practical than the use of plasma specimens, and pooling strategies using plasma specimens have been demonstrated to be an efficient method to reduce costs. This study found that combination of finger-prick dried blood spots and a pooling strategy is a feasible and efficient option to reduce costs, while maintaining accuracy in the context of a district hospital in Malawi.

Viral Meningitis

Science.gov (United States)

... better from treatment such as an antiviral medicine. Antibiotics do not help viral infections, so they are not useful in the treatment of viral meningitis. However, antibiotics do fight bacteria, so they are very important ...

Development and evaluation of a replicon particle vaccine expressing the E2 glycoprotein of bovine viral diarrhea virus (BVDV in cattle

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Loy John Dustin

2013-01-01

Full Text Available Abstract Background Bovine viral diarrhea virus is one of the most significant and costly viral pathogens of cattle worldwide. Alphavirus-derived replicon particles have been shown to be safe and highly effective vaccine vectors against a variety of human and veterinary pathogens. Replicon particles are non-propagating, DIVA compatible, and can induce both humoral and cell mediated immune responses. This is the first experiment to demonstrate that Alphavirus-based replicon particles can be utilized in a standard prime/boost vaccination strategy in calves against a commercially significant bovine pathogen. Findings Replicon particles that express bovine viral diarrhea virus sub-genotype 1b E2 glycoprotein were generated and expression was confirmed in vitro using polyclonal and monoclonal antibodies specific to E2. Vaccine made from particles was generated in Vero cells and administered to BVDV free calves in a prime/boost regimen at two dosage levels. Vaccination resulted in neutralizing antibody titers that cross-neutralized both type 1 and type 2 BVD genotypes following booster vaccination. Additionally, high dose vaccine administration demonstrated some protection from clinical disease and significantly reduced the degree of leukopenia caused by viral infection. Conclusions Replicon particle vaccines administered in a prime/boost regimen expressing BVDV E2 glycoprotein can induce cross-neutralizing titers, reduce leukopenia post challenge, and mitigate clinical disease in calves. This strategy holds promise for a safe and effective vaccine to BVDV.

Effect of oligonucleotide primers in determining viral variability within hosts

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Moya Andrés

2004-12-01

Full Text Available Abstract Background Genetic variability in viral populations is usually estimated by means of polymerase chain reaction (PCR based methods in which the relative abundance of each amplicon is assumed to be proportional to the frequency of the corresponding template in the initial sample. Although bias in template-to-product ratios has been described before, its relevance in describing viral genetic variability at the intrapatient level has not been fully assessed yet. Results To investigate the role of oligonucleotide design in estimating viral variability within hosts, genetic diversity in hepatitis C virus (HCV populations from eight infected patients was characterised by two parallel PCR amplifications performed with two slightly different sets of primers, followed by cloning and sequencing (mean = 89 cloned sequences per patient. Population genetics analyses of viral populations recovered by pairs of amplifications revealed that in seven patients statistically significant differences were detected between populations sampled with different set of primers. Conclusions Genetic variability analyses demonstrates that PCR selection due to the choice of primers, differing in their degeneracy degree at some nucleotide positions, can eclipse totally or partially viral variants, hence yielding significant different estimates of viral variability within a single patient and therefore eventually producing quite different qualitative and quantitative descriptions of viral populations within each host.

Effect of oligonucleotide primers in determining viral variability within hosts.

Science.gov (United States)

Bracho, Maria Alma; García-Robles, Inmaculada; Jiménez, Nuria; Torres-Puente, Manuela; Moya, Andrés; González-Candelas, Fernando

2004-12-09

Genetic variability in viral populations is usually estimated by means of polymerase chain reaction (PCR) based methods in which the relative abundance of each amplicon is assumed to be proportional to the frequency of the corresponding template in the initial sample. Although bias in template-to-product ratios has been described before, its relevance in describing viral genetic variability at the intrapatient level has not been fully assessed yet. To investigate the role of oligonucleotide design in estimating viral variability within hosts, genetic diversity in hepatitis C virus (HCV) populations from eight infected patients was characterised by two parallel PCR amplifications performed with two slightly different sets of primers, followed by cloning and sequencing (mean = 89 cloned sequences per patient). Population genetics analyses of viral populations recovered by pairs of amplifications revealed that in seven patients statistically significant differences were detected between populations sampled with different set of primers. Genetic variability analyses demonstrates that PCR selection due to the choice of primers, differing in their degeneracy degree at some nucleotide positions, can eclipse totally or partially viral variants, hence yielding significant different estimates of viral variability within a single patient and therefore eventually producing quite different qualitative and quantitative descriptions of viral populations within each host.

Translation of a nonpolyadenylated viral RNA is enhanced by binding of viral coat protein or polyadenylation of the RNA.

Science.gov (United States)

Neeleman, L; Olsthoorn, R C; Linthorst, H J; Bol, J F

2001-12-04

On entering a host cell, positive-strand RNA virus genomes have to serve as messenger for the translation of viral proteins. Efficient translation of cellular messengers requires interactions between initiation factors bound to the 5'-cap structure and the poly(A) binding protein bound to the 3'-poly(A) tail. Initiation of infection with the tripartite RNA genomes of alfalfa mosaic virus (AMV) and viruses from the genus Ilarvirus requires binding of a few molecules of coat protein (CP) to the 3' end of the nonpolyadenylated viral RNAs. Moreover, infection with the genomic RNAs can be initiated by addition of the subgenomic messenger for CP, RNA 4. We report here that extension of the AMV RNAs with a poly(A) tail of 40 to 80 A-residues permitted initiation of infection independently of CP or RNA 4 in the inoculum. Specifically, polyadenylation of RNA 1 relieved an apparent bottleneck in the translation of the viral RNAs. Translation of RNA 4 in plant protoplasts was autocatalytically stimulated by its encoded CP. Mutations that interfered with CP binding to the 3' end of viral RNAs reduced translation of RNA 4 to undetectable levels. Possibly, CP of AMV and ilarviruses stimulates translation of viral RNAs by acting as a functional analogue of poly(A) binding protein or other cellular proteins.

High Maternal HIV-1 Viral Load During Pregnancy Is Associated With Reduced Placental Transfer of Measles IgG Antibody

Science.gov (United States)

Farquhar, Carey; Nduati, Ruth; Haigwood, Nancy; Sutton, William; Mbori-Ngacha, Dorothy; Richardson, Barbra; John-Stewart, Grace

2012-01-01

Background Studies among HIV-1–infected women have demonstrated reduced placental transfer of IgG antibodies against measles and other pathogens. As a result, infants born to women with HIV-1 infection may not acquire adequate passive immunity in utero and this could contribute to high infant morbidity and mortality in this vulnerable population. Methods To determine factors associated with decreased placental transfer of measles IgG, 55 HIV-1–infected pregnant women who were enrolled in a Nairobi perinatal HIV-1 transmission study were followed. Maternal CD4 count, HIV-1 viral load, and HIV-1–specific gp41 antibody concentrations were measured antenatally and at delivery. Measles IgG concentrations were assayed in maternal blood and infant cord blood obtained during delivery to calculate placental antibody transfer. Results Among 40 women (73%) with positive measles titers, 30 (75%) were found to have abnormally low levels of maternofetal IgG transfer (<95%). High maternal HIV-1 viral load at 32 weeks’ gestation and at delivery was associated with reductions in placental transfer (P < 0.0001 and P = 0.0056, respectively) and infant measles IgG concentrations in cord blood (P < 0.0001 and P = 0.0073, respectively). High maternal HIV-1–specific gp41 antibody titer was also highly correlated with both decreased placental transfer (P = 0.0080) and decreased infant IgG (P < 0.0001). Conclusions This is the first study to evaluate the relationship between maternal HIV-1 viremia, maternal HIV-1 antibody concentrations, and passive immunity among HIV-1–exposed infants. These data support the hypothesis that high HIV-1 viral load during the last trimester may impair maternofetal transfer of IgG and increases risk of measles and other serious infections among HIV-1–exposed infants. PMID:16280707

Pediatric Viral Exanthema: A Review Article

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Mohammed Jafar Saffar

2017-04-01

Full Text Available Context Many diseases caused by viral agents are associated with fever and cutaneous manifestations. Viral exanthema is a widespread nonspecific skin rash, commonly characterized by generalized eruption of erythematous macules and papular lesions. Although these rashes are mostly benign and self-limited, some may be serious and life-threatening. Differentiation between severe and benign types is clinically important and life-saving. Evidence Acquisition In this narrative review, electronic databases, including Google Scholar, Science Direct, PubMed (including Medline, Web of Science, Scientific Information Database, and Scopus, were searched. We conducted a narrative review of papers published on pediatric viral exanthema during 2000 - 2016. The used keywords included “viral exanthema”, “fever”, and “skin rash”. Articles on skin rash, caused by drug reactions or nonviral exanthema, were excluded. Results Different viral agents can cause different types of skin reactions. Cutaneous manifestations and skin rashes can be categorized, based on the form of the rash (macular, papular, vesicular, blistery, petechial, and purpuric or the general term, which denotes illnesses such as measles-like morbilliform rash, rubella or rubelliform rash, and scarlatiniform rash, a scarlet-fever like infection. Conclusions Based on the findings, a systematic approach relying on accurate history-taking and analysis of epidemiological cues and rash characteristics is of great significance.

A novel mosquito ubiquitin targets viral envelope protein for degradation and reduces virion production during dengue virus infection.

Science.gov (United States)

Troupin, Andrea; Londono-Renteria, Berlin; Conway, Michael J; Cloherty, Erin; Jameson, Samuel; Higgs, Stephen; Vanlandingham, Dana L; Fikrig, Erol; Colpitts, Tonya M

2016-09-01

Dengue virus (DENV) is a mosquito-borne flavivirus that causes significant human disease and mortality in the tropics and subtropics. By examining the effects of virus infection on gene expression, and interactions between virus and vector, new targets for prevention of infection and novel treatments may be identified in mosquitoes. We previously performed a microarray analysis of the Aedes aegypti transcriptome during infection with DENV and found that mosquito ubiquitin protein Ub3881 (AAEL003881) was specifically and highly down-regulated. Ubiquitin proteins have multiple functions in insects, including marking proteins for proteasomal degradation, regulating apoptosis and mediating innate immune signaling. We used qRT-PCR to quantify gene expression and infection, and RNAi to reduce Ub3881 expression. Mosquitoes were infected with DENV through blood feeding. We transfected DENV protein expression constructs to examine the effect of Ub3881 on protein degradation. We used site-directed mutagenesis and transfection to determine what amino acids are involved in Ub3881-mediated protein degradation. Immunofluorescence, Co-immunoprecipitation and Western blotting were used to examine protein interactions and co-localization. The overexpression of Ub3881, but not related ubiquitin proteins, decreased DENV infection in mosquito cells and live Ae. aegypti. The Ub3881 protein was demonstrated to be involved in DENV envelope protein degradation and reduce the number of infectious virions released. We conclude that Ub3881 has several antiviral functions in the mosquito, including specific viral protein degradation. Our data highlights Ub3881 as a target for future DENV prevention strategies in the mosquito transmission vector. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Membrane Bioreactor-Based Wastewater Treatment Plant in Saudi Arabia: Reduction of Viral Diversity, Load, and Infectious Capacity

KAUST Repository

Jumat, Muhammad

2017-07-18

A membrane bioreactor (MBR)-based wastewater treatment plant in Saudi Arabia was assessed over a nine-month period for virus removal efficiency. Viral diversity was detected using omics-based approaches. Log reduction values (LRV) of Adenoviruses (AdV) and Enteroviruses (EV) were enumerated using digital polymerase chain reaction (dPCR) and assessed for infectivity using fluorescence-based infection assays. MBR treatment was successful in reducing viral diversity. Plant viruses remained abundant in the treated effluent. Human enteric viruses were present in lower abundance than plant viruses, and were reduced by MBR at varying LRV. AdV copy numbers were reduced by 3.7-log. Infectious AdV was not detected in the effluent. EV copy numbers were reduced by 1.7-log post MBR and infectious EV decreased by an average of 2.0-log. Infectious EV was detected in the chlorinated effluent, occasionally in concentrations that approximate to its 50% infectious dose. Overall, results indicated that a MBR-based wastewater treatment plant (WWTP) effectively reduces viral diversity, viral load, and infectious capacity by up to 4-logs. These findings suggest potential concerns associated with plant and human enteric viruses for reuse events in this country. Local guidelines for assessment of treated water quality should take into consideration both infectious viral concentration and LRV.

A comprehensive and quantitative exploration of thousands of viral genomes

Science.gov (United States)

Mahmoudabadi, Gita

2018-01-01

The complete assembly of viral genomes from metagenomic datasets (short genomic sequences gathered from environmental samples) has proven to be challenging, so there are significant blind spots when we view viral genomes through the lens of metagenomics. One approach to overcoming this problem is to leverage the thousands of complete viral genomes that are publicly available. Here we describe our efforts to assemble a comprehensive resource that provides a quantitative snapshot of viral genomic trends – such as gene density, noncoding percentage, and abundances of functional gene categories – across thousands of viral genomes. We have also developed a coarse-grained method for visualizing viral genome organization for hundreds of genomes at once, and have explored the extent of the overlap between bacterial and bacteriophage gene pools. Existing viral classification systems were developed prior to the sequencing era, so we present our analysis in a way that allows us to assess the utility of the different classification systems for capturing genomic trends. PMID:29624169

Hepatitis viral aguda

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Héctor Rubén Hernández Garcés

1998-10-01

Full Text Available Se realizó una revisión bibliográfica de las hepatitis virales agudas sobre aspectos vinculados a su etiología. Se tuvieron en cuenta además algunos datos epidemiológicos, las formas clínicas más importantes, los exámenes complementarios con especial énfasis en los marcadores virales y el diagnóstico positivoA bibliographical review of acute viral hepatitis was made taking into account those aspects connected with its etiology. Some epidemiological markers, the most important clinical forms, and the complementary examinations with special emphasis on the viral markers and the positive diagnosis were also considered

View and review on viral oncology research

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Parolin Cristina

2010-05-01

Full Text Available Abstract To date, almost one and a half million cases of cancer are diagnosed every year in the US and nearly 560,000 Americans are expected to die of cancer in the current year, more than 1,500 people a day (data from the American Cancer Society at http://www.cancer.org/. According to the World Health Organization (WHO, roughly 20% of all cancers worldwide results from chronic infections; in particular, up to 15% of human cancers is characterized by a viral aetiology with higher incidence in Developing Countries. The link between viruses and cancer was one of the pivotal discoveries in cancer research during the past Century. Indeed, the infectious nature of specific tumors has important implications in terms of their prevention, diagnosis, and therapy. In the 21st Century, the research on viral oncology field continues to be vigorous, with new significant and original studies on viral oncogenesis and translational research from basic virology to treatment of cancer. This review will cover different viral oncology aspects, starting from the history of viral oncology and moving to the peculiar features of oncogenic RNA and DNA viruses, with a special focus on human pathogens.

Virale commercials: de consument als marketeer. Onderzoek naar de redenen waarom consumenten virale commercials doorsturen: hun motieven, de inhoudskenmerken van viral commercials en de mediumcontext waarin virale commercials verschijnen

NARCIS (Netherlands)

Ketelaar, P.E.; Lucassen, P.; Kregting, G.H.J.

2010-01-01

Research into the reasons why consumers pass along viral commercials: their motives, the content characteristics of viral commercials and the medium context in which viral commercials appear. Based on the uses and gratifications perspective this study has determined which motives of consumers,

Viral Disease Networks?

Science.gov (United States)

Gulbahce, Natali; Yan, Han; Vidal, Marc; Barabasi, Albert-Laszlo

2010-03-01

Viral infections induce multiple perturbations that spread along the links of the biological networks of the host cells. Understanding the impact of these cascading perturbations requires an exhaustive knowledge of the cellular machinery as well as a systems biology approach that reveals how individual components of the cellular system function together. Here we describe an integrative method that provides a new approach to studying virus-human interactions and its correlations with diseases. Our method involves the combined utilization of protein - protein interactions, protein -- DNA interactions, metabolomics and gene - disease associations to build a ``viraldiseasome''. By solely using high-throughput data, we map well-known viral associated diseases and predict new candidate viral diseases. We use microarray data of virus-infected tissues and patient medical history data to further test the implications of the viral diseasome. We apply this method to Epstein-Barr virus and Human Papillomavirus and shed light into molecular development of viral diseases and disease pathways.

Supplementary Material for: CRISPR/Cas9-mediated viral interference in plants

KAUST Repository

Ali, Zahir; Abulfaraj, Aala A.; Idris, Ali; Ali, Shakila; Tashkandi, Manal; Mahfouz, Magdy

2015-01-01

Abstract Background The CRISPR/Cas9 system provides bacteria and archaea with molecular immunity against invading phages and conjugative plasmids. Recently, CRISPR/Cas9 has been used for targeted genome editing in diverse eukaryotic species. Results In this study, we investigate whether the CRISPR/Cas9 system could be used in plants to confer molecular immunity against DNA viruses. We deliver sgRNAs specific for coding and non-coding sequences of tomato yellow leaf curl virus (TYLCV) into Nicotiana benthamiana plants stably overexpressing the Cas9 endonuclease, and subsequently challenge these plants with TYLCV. Our data demonstrate that the CRISPR/Cas9 system targeted TYLCV for degradation and introduced mutations at the target sequences. All tested sgRNAs exhibit interference activity, but those targeting the stem-loop sequence within the TYLCV origin of replication in the intergenic region (IR) are the most effective. N. benthamiana plants expressing CRISPR/Cas9 exhibit delayed or reduced accumulation of viral DNA, abolishing or significantly attenuating symptoms of infection. Moreover, this system could simultaneously target multiple DNA viruses. Conclusions These data establish the efficacy of the CRISPR/Cas9 system for viral interference in plants, thereby extending the utility of this technology and opening the possibility of producing plants resistant to multiple viral infections.

Mucosal immunization with recombinant adenoviral vectors expressing murine gammaherpesvirus-68 genes M2 and M3 can reduce latent viral load

DEFF Research Database (Denmark)

Hoegh-Petersen, Mette; Thomsen, Allan R; Christensen, Jan P

2009-01-01

-68 (MHV-68) is a member of the Gammaherpesvirinae subfamily and represents a useful murine model for this category of infections, in which new vaccination strategies may initially be evaluated. Two attenuated variants of MHV-68 have successfully been used as vaccines, but the oncogenic potential...... of the gammaherpesvirinae speaks against using a similar approach in humans. DNA immunization with plasmids encoding the MHV-68 genes M2 or M3 caused a reduction in either acute or early latent viral load, respectively, but neither immunization had an effect at times later than 14 days post-infection. Adenovirus......-based vaccines are substantially more immunogenic than DNA vaccines and can be applied to induce mucosal immunity. Here we show that a significant reduction of the late viral load in the spleens, at 60 days post-infection, was achieved when immunizing mice both intranasally and subcutaneously with adenoviral...

Sensitive detection of viral transcripts in human tumor transcriptomes.

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Sven-Eric Schelhorn

Full Text Available In excess of 12% of human cancer incidents have a viral cofactor. Epidemiological studies of idiopathic human cancers indicate that additional tumor viruses remain to be discovered. Recent advances in sequencing technology have enabled systematic screenings of human tumor transcriptomes for viral transcripts. However, technical problems such as low abundances of viral transcripts in large volumes of sequencing data, viral sequence divergence, and homology between viral and human factors significantly confound identification of tumor viruses. We have developed a novel computational approach for detecting viral transcripts in human cancers that takes the aforementioned confounding factors into account and is applicable to a wide variety of viruses and tumors. We apply the approach to conducting the first systematic search for viruses in neuroblastoma, the most common cancer in infancy. The diverse clinical progression of this disease as well as related epidemiological and virological findings are highly suggestive of a pathogenic cofactor. However, a viral etiology of neuroblastoma is currently contested. We mapped 14 transcriptomes of neuroblastoma as well as positive and negative controls to the human and all known viral genomes in order to detect both known and unknown viruses. Analysis of controls, comparisons with related methods, and statistical estimates demonstrate the high sensitivity of our approach. Detailed investigation of putative viral transcripts within neuroblastoma samples did not provide evidence for the existence of any known human viruses. Likewise, de-novo assembly and analysis of chimeric transcripts did not result in expression signatures associated with novel human pathogens. While confounding factors such as sample dilution or viral clearance in progressed tumors may mask viral cofactors in the data, in principle, this is rendered less likely by the high sensitivity of our approach and the number of biological replicates

Plasma Viral miRNAs Indicate a High Prevalence of Occult Viral Infections

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Enrique Fuentes-Mattei

2017-06-01

Full Text Available Prevalence of Kaposi sarcoma-associated herpesvirus (KSHV/HHV-8 varies greatly in different populations. We hypothesized that the actual prevalence of KSHV/HHV8 infection in humans is underestimated by the currently available serological tests. We analyzed four independent patient cohorts with post-surgical or post-chemotherapy sepsis, chronic lymphocytic leukemia and post-surgical patients with abdominal surgical interventions. Levels of specific KSHV-encoded miRNAs were measured by reverse transcription-quantitative polymerase chain reaction (RT-qPCR, and KSHV/HHV-8 IgG were measured by immunoassay. We also measured specific miRNAs from Epstein Barr Virus (EBV, a virus closely related to KSHV/HHV-8, and determined the EBV serological status by ELISA for Epstein-Barr nuclear antigen 1 (EBNA-1 IgG. Finally, we identified the viral miRNAs by in situ hybridization (ISH in bone marrow cells. In training/validation settings using independent multi-institutional cohorts of 300 plasma samples, we identified in 78.50% of the samples detectable expression of at least one of the three tested KSHV-miRNAs by RT-qPCR, while only 27.57% of samples were found to be seropositive for KSHV/HHV-8 IgG (P < 0.001. The prevalence of KSHV infection based on miRNAs qPCR is significantly higher than the prevalence determined by seropositivity, and this is more obvious for immuno-depressed patients. Plasma viral miRNAs quantification proved that EBV infection is ubiquitous. Measurement of viral miRNAs by qPCR has the potential to become the “gold” standard method to detect certain viral infections in clinical practice.

Mobil Viral Pazarlama

OpenAIRE

Barutçu, Süleyman

2011-01-01

OBJECTIVE: Mobile Viral Marketing, with using mobile phones, is one of the most importantinnovations after Word of Mouth Marketing performed by face to face amongpeople and Viral Marketing performed in the İnternet. The main objective of thisstudy is to call marketing communicators’ and academicians’ attentions whowant to increase the recognition of companies’ products, services and brands tobecome a current issue in the marketplace using Mobile Viral Marketingapplications by reason of techno...

Eradication of viral haemorrhagic septicaemia in Danish aquaculture

DEFF Research Database (Denmark)

Olsen, N. J.; Skall, Helle Frank; Jensen, B. B.

2013-01-01

resources have been used to control and eradicate the disease. The control program included strict biosecurity and preventative measures, trade regulations, zoning and intensive inspections and laboratory testing. During the first decades of control and eradication programs the number of infected farms......Viral haemorrhagic septicaemia (VHS) virus was first isolated in Denmark in 1962, when more than half of the approximately 800 Danish fish farms were considered to be infected. Today, 50 years later, the country obtained status as EU approved VHS free zone. In the years in between very significant...... was significantly reduced while the curve flattened the last 20 years. It was only after a large and costly coordinated action in 2009-2013 including all affected areas that the country managed to free itself totally from VHS. Molecular tracing of the origin of VHSV isolates revealed that despite strict trade...

Understanding Image Virality

Science.gov (United States)

2015-06-07

Example non-viral images. Figure 1: Top: Images with high viral scores in our dataset depict internet “celebrity” memes ex. “Grumpy Cat”; Bottom: Images...of images that is most similar to ours is the concurrently introduced viral meme generator of Wang et al., that combines NLP and Computer Vision (low...doing any of our tasks. The test included questions about widely spread Reddit memes and jargon so that anyone familiar with Reddit can easily get a high

Progress in diagnosis of viral hepatitis A, B, C, D and E

International Nuclear Information System (INIS)

Kurstak, E.; Hossain, A.; Kurstak, C.

1996-01-01

The effective use of new molecular biological techniques towards the reliable diagnosis of HCV and other viral liver infections has been updated in this review. The applications PCR techniques with amplification of reverse transcribed cDNA seems to prove an effective means for assaying HCV infections. A very recent one-stage PCR assay of HCV RNA combined with either liquid hybridization or Southern blot analysis, equal in sensitivity to the nested PCR assay but with sharply reduced potential for contamination appears to be promising. Future further development of reliable and automated RT-PCR assay would be particularly interesting for diagnosis of HCV infections. PCR apparently remains the most useful test for the appraisal of HBV infection in sera-negative patients with liver disease. It has now made possible the confirmation of observations made with the spot blot or Southern blot test and provided access to the nucleotide sequence analysis of these viral mutant forms. The rapidity and simplicity of these viral forms. The rapidity and simplicity of the the newly developed latex agglutination method using ISTA also makes it a viable alternative for the determination of HBsAg. Cloning of HEV, sequencing of the viral genome and expression of recombinant HEV proteins has undoubtedly facilitated significant progress in the development of methods for identification of HEV infection in patients. Recently the availability of specific, more sensitive assays as recombinant-based EIAs has made the diagnosis of hepatitis E very much practicable. (author)

ANTI-VIRAL ACTIVITY OF GLYCIRRHETINIC AND GLYCIRRHIZIC ACIDS

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V. V. Zarubaev

2016-01-01

Full Text Available Influenza is a highly contagious human disease. In the course of use of antiviral drugs drug-resistant strains of the virus are formed, resulting in reduced efficiency of the chemotherapy. The review describes the biological activity of glycirrhetinic (GLA and glycirrhizic (GA acids in terms of their use as a therapeutic agent for viral infections. So, these compounds are against a broad spectrum of viruses, including herpes, corona-, alphaand flaviviruses, human immunodeficiency virus, vaccinia virus, poliovirus type I, vesicular stomatitis virus and influenza A virus. These data indicate that anti-viral effect of these compounds is due to several types of activity — direct antiviral effects, effects on cellular proand anti-viral and immunomodulating pathways, in particular by activation of innate immunity system. GA interferes with early steps of the viral reproductive cycle such as virus binding to its receptor, the absorption of the virus by endocytosis or virus decapsidation in the cytoplasm. This is due to the effect of GA-induced reduction of membrane fluidity. Thus, one mechanism for the antiviral activity of GA is that GA molecule increases the rigidity of cellular and viral membranes after incorporation in there. This results in increasing of energy threshold required for the formation of negative curvature at the fusion zones, as well as difficult lateral migration of the virus-receptor complexes. In addition, glycyrrhizin prevents interaction of viral nucleoprotein with cellular protein HMGB1, which is necessary for the viral life cycle. Glycyrrhizin also inhibits the induction of oxidative stress during influenza infection, exhibiting antioxidant properties, which leads to a reduction of virus-induced production of cytokines/chemokines, without affecting the replication of the virus. A wide spectrum of biological activity and effect on various aspects of the viral pathogenesis substantiate the effect of GA and GLA as a component

Synaptogyrin-2 Promotes Replication of a Novel Tick-borne Bunyavirus through Interacting with Viral Nonstructural Protein NSs*

Science.gov (United States)

Sun, Qiyu; Qi, Xian; Zhang, Yan; Wu, Xiaodong; Liang, Mifang; Li, Chuan; Li, Dexin; Cardona, Carol J.; Xing, Zheng

2016-01-01

Synaptogyrin-2 is a non-neuronal member of the synaptogyrin family involved in synaptic vesicle biogenesis and trafficking. Little is known about the function of synaptogyrin-2. Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease characterized by high fever, thrombocytopenia, and leukocytopenia with high mortality, caused by a novel tick-borne phlebovirus in the family Bunyaviridae. Our previous studies have shown that the viral nonstructural protein NSs forms inclusion bodies (IBs) that are involved in viral immune evasion, as well as viral RNA replication. In this study, we sought to elucidate the mechanism by which NSs formed the IBs, a lipid droplet-based structure confirmed by NSs co-localization with perilipin A and adipose differentiation-related protein (ADRP). Through a high throughput screening, we identified synaptogyrin-2 to be highly up-regulated in response to SFTS bunyavirus (SFTSV) infection and to be a promoter of viral replication. We demonstrated that synaptogyrin-2 interacted with NSs and was translocated into the IBs, which were reconstructed from lipid droplets into large structures in infection. Viral RNA replication decreased, and infectious virus titers were lowered significantly when synaptogyrin-2 was silenced in specific shRNA-expressing cells, which correlated with the reduced number of the large IBs restructured from regular lipid droplets. We hypothesize that synaptogyrin-2 is essential to promoting the formation of the IBs to become virus factories for viral RNA replication through its interaction with NSs. These findings unveil the function of synaptogyrin-2 as an enhancer in viral infection. PMID:27226560

Inhibition of viral replication reduces regulatory T cells and enhances the antiviral immune response in chronic hepatitis B

International Nuclear Information System (INIS)

Stoop, Jeroen N.; Molen, Renate G. van der; Kuipers, Ernst J.; Kusters, Johannes G.; Janssen, Harry L.A.

2007-01-01

Regulatory T cells (Treg) play a key role in the impaired immune response that is typical for a chronic Hepatitis B virus (HBV) infection. To gain more insight in the mechanism that is responsible for this impaired immune response, the effect of viral load reduction resulting from treatment with the nucleotide analogue adefovir dipivoxil on the percentages of Treg and HBV-specific T-cell responses was analyzed. Peripheral blood mononuclear cells (PBMC) of 12 patients were collected at baseline and during treatment. In parallel to the decline in viral load, we found a decline in circulating Treg, combined with an increase in HBV core antigen-specific IFN-γ production and proliferation. The production of IL10 did not decrease during therapy. In conclusion, adefovir induced viral load reduction results in a decline of circulating Treg together with a partial recovery of the immune response

Anti-metastatic effects of viral and non-viral mediated Nk4 delivery to tumours.

Science.gov (United States)

Buhles, Alexandra; Collins, Sara A; van Pijkeren, Jan P; Rajendran, Simon; Miles, Michelle; O'Sullivan, Gerald C; O'Hanlon, Deirdre M; Tangney, Mark

2009-03-09

The most common cause of death of cancer sufferers is through the occurrence of metastases. The metastatic behaviour of tumour cells is regulated by extracellular growth factors such as hepatocyte growth factor (HGF), a ligand for the c-Met receptor tyrosine kinase, and aberrant expression/activation of the c-Met receptor is closely associated with metastatic progression. Nk4 (also known as Interleukin (IL)32b) is a competitive antagonist of the HGF c-Met system and inhibits c-Met signalling and tumour metastasis. Nk4 has an additional anti-angiogenic activity independent of its HGF-antagonist function. Angiogenesis-inhibitory as well as cancer-specific apoptosis inducing effects make the Nk4 sequence an attractive candidate for gene therapy of cancer. This study investigates the inhibition of tumour metastasis by gene therapy mediated production of Nk4 by the primary tumour. Optimal delivery of anti-cancer genes is vital in order to achieve the highest therapeutic responses. Non-viral plasmid delivery methods have the advantage of safety and ease of production, providing immediate transgene expression, albeit short-lived in most tumours. Sustained presence of anti-angiogenic molecules is preferable with anti-angiogenic therapies, and the long-term expression mediated by Adeno-associated Virus (AAV) might represent a more appropriate delivery in this respect. However, the incubation time required by AAV vectors to reach appropriate gene expression levels hampers efficacy in many fast-growing murine tumour models. Here, we describe murine trials assessing the effects of Nk4 on the spontaneously metastatic Lewis Lung Carcinoma (LLC) model when delivered to primary tumour via plasmid lipofection or AAV2 vector. Intratumoural AAV-Nk4 administration produced the highest therapeutic response with significant reduction in both primary tumour growth and incidence of lung metastases. Plasmid-mediated therapy also significantly reduced metastatic growth, but with moderate

Bile acids for viral hepatitis

DEFF Research Database (Denmark)

Chen, Weikeng; Liu, J; Gluud, C

2003-01-01

The viral hepatitides are common causes of liver diseases globally. Trials have assessed bile acids for patients with viral hepatitis, but no consensus was reached regarding their usefulness.......The viral hepatitides are common causes of liver diseases globally. Trials have assessed bile acids for patients with viral hepatitis, but no consensus was reached regarding their usefulness....

Viral hemorrhagic septicemia

Science.gov (United States)

Batts, William N.; Winton, James R.

2012-01-01

Viral hemorrhagic septicemia (VHS) is one of the most important viral diseases of finfish worldwide. In the past, VHS was thought to affect mainly rainbow trout Oncorhynchus mykiss reared at freshwater facilities in Western Europe where it was known by various names including Egtved disease and infectious kidney swelling and liver degeneration (Wolf 1988). Today, VHS is known as an important source of mortality for cultured and wild fish in freshwater and marine environments in several regions of the northern hemisphere (Dixon 1999; Gagné et al. 2007; Kim and Faisal 2011; Lumsden et al. 2007; Marty et al. 1998, 2003; Meyers and Winton 1995; Skall et al. 2005b; Smail 1999; Takano et al. 2001). Viral hemorrhagic septicemia is caused by the fish rhabdovirus, viral hemorrhagic septicemia virus (VHSV), a member of the genus Novirhabdovirus of the family Rhabdoviridae

Improved osteogenic vector for non-viral gene therapy

Directory of Open Access Journals (Sweden)

ARA Hacobian

2016-03-01

Full Text Available Therapeutic compensation of deficient bone regeneration is a challenging task and a topic of on-going search for novel treatment strategies. One promising approach for improvement involves non-viral gene delivery using the bone morphogenetic protein-2 (BMP-2 gene to provide transient, local and sustained expression of the growth factor. However, since efficiency of non-viral gene delivery is low, this study focused on the improvement of a BMP-2 gene expression system, aiming for compensation of poor transfection efficiency. First, the native BMP-2 gene sequence was modified by codon optimisation and altered by inserting a highly truncated artificial intron (96 bp. Transfection of multiple cell lines and rat adipose-derived mesenchymal stem cells with plasmids harbouring the improved BMP-2 sequence led to a several fold increased expression rate and subsequent osteogenic differentiation. Additionally, comparing expression kinetics of elongation factor 1 alpha (EF1α promoter with a state of the art CMV promoter revealed significantly higher BMP-2 expression when under the influence of the EF1α promoter. Results obtained by quantification of bone markers as well as osteogenic assays showed reduced sensitivity to promoter silencing effects of the EF1α promoter in rat adipose-derived mesenchymal stem cells. Finally, screening of several protein secretion signals using either luciferase or BMP-2 as reporter protein revealed no superior candidates for potential replacement of the native BMP-2 secretion signal. Taken together, by enhancing the exogenous BMP-2 expression system, low transfection efficiencies in therapeutic applications can be compensated, making safe non-viral systems even more suitable for tissue regeneration approaches.

Differential impact of transplantation on peripheral and tissue-associated viral reservoirs: Implications for HIV gene therapy.

Science.gov (United States)

Peterson, Christopher W; Wang, Jianbin; Deleage, Claire; Reddy, Sowmya; Kaur, Jasbir; Polacino, Patricia; Reik, Andreas; Huang, Meei-Li; Jerome, Keith R; Hu, Shiu-Lok; Holmes, Michael C; Estes, Jacob D; Kiem, Hans-Peter

2018-04-01

Autologous transplantation and engraftment of HIV-resistant cells in sufficient numbers should recapitulate the functional cure of the Berlin Patient, with applicability to a greater number of infected individuals and with a superior safety profile. A robust preclinical model of suppressed HIV infection is critical in order to test such gene therapy-based cure strategies, both alone and in combination with other cure strategies. Here, we present a nonhuman primate (NHP) model of latent infection using simian/human immunodeficiency virus (SHIV) and combination antiretroviral therapy (cART) in pigtail macaques. We demonstrate that transplantation of CCR5 gene-edited hematopoietic stem/progenitor cells (HSPCs) persist in infected and suppressed animals, and that protected cells expand through virus-dependent positive selection. CCR5 gene-edited cells are readily detectable in tissues, namely those closely associated with viral reservoirs such as lymph nodes and gastrointestinal tract. Following autologous transplantation, tissue-associated SHIV DNA and RNA levels in suppressed animals are significantly reduced (p ≤ 0.05), relative to suppressed, untransplanted control animals. In contrast, the size of the peripheral reservoir, measured by QVOA, is variably impacted by transplantation. Our studies demonstrate that CCR5 gene editing is equally feasible in infected and uninfected animals, that edited cells persist, traffic to, and engraft in tissue reservoirs, and that this approach significantly reduces secondary lymphoid tissue viral reservoir size. Our robust NHP model of HIV gene therapy and viral persistence can be immediately applied to the investigation of combinatorial approaches that incorporate anti-HIV gene therapy, immune modulators, therapeutic vaccination, and latency reversing agents.

Differential impact of transplantation on peripheral and tissue-associated viral reservoirs: Implications for HIV gene therapy.

Directory of Open Access Journals (Sweden)

Christopher W Peterson

2018-04-01

Full Text Available Autologous transplantation and engraftment of HIV-resistant cells in sufficient numbers should recapitulate the functional cure of the Berlin Patient, with applicability to a greater number of infected individuals and with a superior safety profile. A robust preclinical model of suppressed HIV infection is critical in order to test such gene therapy-based cure strategies, both alone and in combination with other cure strategies. Here, we present a nonhuman primate (NHP model of latent infection using simian/human immunodeficiency virus (SHIV and combination antiretroviral therapy (cART in pigtail macaques. We demonstrate that transplantation of CCR5 gene-edited hematopoietic stem/progenitor cells (HSPCs persist in infected and suppressed animals, and that protected cells expand through virus-dependent positive selection. CCR5 gene-edited cells are readily detectable in tissues, namely those closely associated with viral reservoirs such as lymph nodes and gastrointestinal tract. Following autologous transplantation, tissue-associated SHIV DNA and RNA levels in suppressed animals are significantly reduced (p ≤ 0.05, relative to suppressed, untransplanted control animals. In contrast, the size of the peripheral reservoir, measured by QVOA, is variably impacted by transplantation. Our studies demonstrate that CCR5 gene editing is equally feasible in infected and uninfected animals, that edited cells persist, traffic to, and engraft in tissue reservoirs, and that this approach significantly reduces secondary lymphoid tissue viral reservoir size. Our robust NHP model of HIV gene therapy and viral persistence can be immediately applied to the investigation of combinatorial approaches that incorporate anti-HIV gene therapy, immune modulators, therapeutic vaccination, and latency reversing agents.

UGGT1 enhances enterovirus 71 pathogenicity by promoting viral RNA synthesis and viral replication.

Directory of Open Access Journals (Sweden)

Peng-Nien Huang

2017-05-01

Full Text Available Positive-strand RNA virus infections can induce the stress-related unfolded protein response (UPR in host cells. This study found that enterovirus A71 (EVA71 utilizes host UDP-glucose glycoprotein glucosyltransferase 1 (UGGT1, a key endoplasmic reticulum protein (ER involved in UPR, to enhance viral replication and virulence. EVA71 forms replication complexes (RCs on cellular membranes that contain a mix of host and viral proteins to facilitate viral replication, but the components and processes involved in the assembly and function of RCs are not fully understood. Using EVA71 as a model, this study found that host UGGT1 and viral 3D polymerase co-precipitate along with other factors on membranous replication complexes to enhance viral replication. Increased UGGT1 levels elevated viral growth rates, while viral pathogenicity was observed to be lower in heterozygous knockout mice (Uggt1 +/- mice. These findings provide important insight on the role of UPR and host UGGT1 in regulating RNA virus replication and pathogenicity.

Mechanism of action and application of virocids in health care-associated viral infections

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Babak Shahbaz

2016-03-01

Full Text Available Viruses are important causes of acute and chronic diseases in humans. Newer viruses are still being discovered. Apart from frequently causing infections in the general community, many types of viruses are significant nosocomial pathogens that with emerging viruses has become a real issue in medical field. There are specific treatments, vaccine and physical barrier to fight some of these infections. Health care-associated viral infections are an important source of patient’s morbidity and mortality. The method of sterilization or disinfection depends on the intended use of the medical devices (comprising critical, semicritical and noncritical items and failure to perform proper sterilization or disinfection of these items may leads to introduction of viruses, resulting in infection. Disinfection is an essential way in reducing or disruption of transmission of viruses by environmental surfaces, instruments and hands which achieves by chemical disinfectants and antiseptics, respectively. This review discusses about chemical agents with virocids properties (e.g. alcohols, chlorine compounds, formaldehyde, phenolic compounds, glutaraldehyde, ortho-phthaldehyde, hydrogen peroxide, peracetic acid, iodophor, ammonium compounds quaternary, bigunides and so on., mechanisms of action and their applications in health care-associated viral infection control. As well as, we described an overview for hierarchy of viruses in challenge with disinfantans, effective agents on viral inactivation, i.e.targect viruses, viral stability or survival duration time in enviromental surfaces and hands. We explained disinfection of surfaces, challenges in emerging viral pathogens inactivation, viral resistance to chemical disinfectants and antiseptics. Because, there are laboratory studies and clinical evidences for some viruses which viral resistance to biocide or failure to perform proper disinfection can lead to infection outbreaks. Also, we described virucidal

Human cytomegalovirus uracil DNA glycosylase associates with ppUL44 and accelerates the accumulation of viral DNA

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Dixon Melissa

2005-07-01

Full Text Available Abstract Background Human cytomegalovirus UL114 encodes a uracil-DNA glycosylase homolog that is highly conserved in all characterized herpesviruses that infect mammals. Previous studies demonstrated that the deletion of this nonessential gene delays significantly the onset of viral DNA synthesis and results in a prolonged replication cycle. The gene product, pUL114, also appears to be important in late phase DNA synthesis presumably by introducing single stranded breaks. Results A series of experiments was performed to formally assign the observed phenotype to pUL114 and to characterize the function of the protein in viral replication. A cell line expressing pUL114 complemented the observed phenotype of a UL114 deletion virus in trans, confirming that the observed defects were the result of a deficiency in this gene product. Stocks of recombinant viruses without elevated levels of uracil were produced in the complementing cells; however they retained the phenotype of poor growth in normal fibroblasts suggesting that poor replication was unrelated to uracil content of input genomes. Recombinant viruses expressing epitope tagged versions of this gene demonstrated that pUL114 was expressed at early times and that it localized to viral replication compartments. This protein also coprecipitated with the DNA polymerase processivity factor, ppUL44 suggesting that these proteins associate in infected cells. This apparent interaction did not appear to require other viral proteins since ppUL44 could recruit pUL114 to the nucleus in uninfected cells. An analysis of DNA replication kinetics revealed that the initial rate of DNA synthesis and the accumulation of progeny viral genomes were significantly reduced compared to the parent virus. Conclusion These data suggest that pUL114 associates with ppUL44 and that it functions as part of the viral DNA replication complex to increase the efficiency of both early and late phase viral DNA synthesis.

Viral Marketing

OpenAIRE

Sorina Raula Gîrboveanu; Silvia Puiu

2008-01-01

With consumers showing increasing resistance to traditional forms of advertising such as TV or newspaper ads, marketers have turned to alternate strategies, including viral marketing. Viral marketing exploits existing social networks by encouraging customers to share product information with their friends.In our study we are able to directly observe the effectiveness of person to person word of mouth advertising for hundreds of thousands of products for the first time

[Immunotherapy for refractory viral infections].

Science.gov (United States)

Morio, Tomohiro; Fujita, Yuriko; Takahashi, Satoshi

Various antiviral agents have been developed, which are sometimes associated with toxicity, development of virus-resistant strain, and high cost. Virus-specific T-cell (VST) therapy provides an alternative curative therapy that can be effective for a prolonged time without eliciting drug resistance. VSTs can be directly separated using several types of capture devices and can be obtained by stimulating peripheral blood mononuclear cells with viral antigens (virus, protein, or peptide) loaded on antigen-presenting cells (APC). APC can be transduced with virus-antigen coding plasmid or pulsed with overlapping peptides. VST therapy has been studied in drug non-responsive viral infections after hematopoietic cell transplantation (HCT). Several previous studies have demonstrated the efficacy of VST therapy without significant severe GVHD. In addition, VSTs from a third-party donor have been prepared and administered for post-HCT viral infection. Although target viruses of VSTs include herpes virus species and polyomavirus species, a wide variety of pathogens, such as papillomavirus, intracellular bacteria, and fungi, can be treated by pathogen-specific T-cells. Perhaps, these specific T-cells could be used for opportunistic infections in other immunocompromised hosts in the near future.

Complexities in Isolation and Purification of Multiple Viruses from Mixed Viral Infections: Viral Interference, Persistence and Exclusion.

Directory of Open Access Journals (Sweden)

Naveen Kumar

Full Text Available Successful purification of multiple viruses from mixed infections remains a challenge. In this study, we investigated peste des petits ruminants virus (PPRV and foot-and-mouth disease virus (FMDV mixed infection in goats. Rather than in a single cell type, cytopathic effect (CPE of the virus was observed in cocultured Vero/BHK-21 cells at 6th blind passage (BP. PPRV, but not FMDV could be purified from the virus mixture by plaque assay. Viral RNA (mixture transfection in BHK-21 cells produced FMDV but not PPRV virions, a strategy which we have successfully employed for the first time to eliminate the negative-stranded RNA virus from the virus mixture. FMDV phenotypes, such as replication competent but noncytolytic, cytolytic but defective in plaque formation and, cytolytic but defective in both plaque formation and standard FMDV genome were observed respectively, at passage level BP8, BP15 and BP19 and hence complicated virus isolation in the cell culture system. Mixed infection was not found to induce any significant antigenic and genetic diversity in both PPRV and FMDV. Further, we for the first time demonstrated the viral interference between PPRV and FMDV. Prior transfection of PPRV RNA, but not Newcastle disease virus (NDV and rotavirus RNA resulted in reduced FMDV replication in BHK-21 cells suggesting that the PPRV RNA-induced interference was specifically directed against FMDV. On long-term coinfection of some acute pathogenic viruses (all possible combinations of PPRV, FMDV, NDV and buffalopox virus in Vero cells, in most cases, one of the coinfecting viruses was excluded at passage level 5 suggesting that the long-term coinfection may modify viral persistence. To the best of our knowledge, this is the first documented evidence describing a natural mixed infection of FMDV and PPRV. The study not only provides simple and reliable methodologies for isolation and purification of two epidemiologically and economically important groups of

An acutely and latently expressed herpes simplex virus 2 viral microRNA inhibits expression of ICP34.5, a viral neurovirulence factor.

Science.gov (United States)

Tang, Shuang; Bertke, Andrea S; Patel, Amita; Wang, Kening; Cohen, Jeffrey I; Krause, Philip R

2008-08-05

Latency-associated transcript (LAT) sequences regulate herpes simplex virus (HSV) latency and reactivation from sensory neurons. We found a HSV-2 LAT-related microRNA (miRNA) designated miR-I in transfected and infected cells in vitro and in acutely and latently infected ganglia of guinea pigs in vivo. miR-I is also expressed in human sacral dorsal root ganglia latently infected with HSV-2. miR-I is expressed under the LAT promoter in vivo in infected sensory ganglia. We also predicted and identified a HSV-1 LAT exon-2 viral miRNA in a location similar to miR-I, implying a conserved mechanism in these closely related viruses. In transfected and infected cells, miR-I reduces expression of ICP34.5, a key viral neurovirulence factor. We hypothesize that miR-I may modulate the outcome of viral infection in the peripheral nervous system by functioning as a molecular switch for ICP34.5 expression.

An integrated approach to elucidate the intra-viral and viral-cellular protein interaction networks of a gamma-herpesvirus.

Directory of Open Access Journals (Sweden)

Shaoying Lee

2011-10-01

Full Text Available Genome-wide yeast two-hybrid (Y2H screens were conducted to elucidate the molecular functions of open reading frames (ORFs encoded by murine γ-herpesvirus 68 (MHV-68. A library of 84 MHV-68 genes and gene fragments was generated in a Gateway entry plasmid and transferred to Y2H vectors. All possible pair-wise interactions between viral proteins were tested in the Y2H assay, resulting in the identification of 23 intra-viral protein-protein interactions (PPIs. Seventy percent of the interactions between viral proteins were confirmed by co-immunoprecipitation experiments. To systematically investigate virus-cellular protein interactions, the MHV-68 Y2H constructs were screened against a cellular cDNA library, yielding 243 viral-cellular PPIs involving 197 distinct cellar proteins. Network analyses indicated that cellular proteins targeted by MHV-68 had more partners in the cellular PPI network and were located closer to each other than expected by chance. Taking advantage of this observation, we scored the cellular proteins based on their network distances from other MHV-68-interacting proteins and segregated them into high (Y2H-HP and low priority/not-scored (Y2H-LP/NS groups. Significantly more genes from Y2H-HP altered MHV-68 replication when their expression was inhibited with siRNAs (53% of genes from Y2H-HP, 21% of genes from Y2H-LP/NS, and 16% of genes randomly chosen from the human PPI network; p<0.05. Enriched Gene Ontology (GO terms in the Y2H-HP group included regulation of apoptosis, protein kinase cascade, post-translational protein modification, transcription from RNA polymerase II promoter, and IκB kinase/NFκB cascade. Functional validation assays indicated that PCBP1, which interacted with MHV-68 ORF34, may be involved in regulating late virus gene expression in a manner consistent with the effects of its viral interacting partner. Our study integrated Y2H screening with multiple functional validation approaches to create �

Physical non-viral gene delivery methods for tissue engineering.

Science.gov (United States)

Mellott, Adam J; Forrest, M Laird; Detamore, Michael S

2013-03-01

The integration of gene therapy into tissue engineering to control differentiation and direct tissue formation is not a new concept; however, successful delivery of nucleic acids into primary cells, progenitor cells, and stem cells has proven exceptionally challenging. Viral vectors are generally highly effective at delivering nucleic acids to a variety of cell populations, both dividing and non-dividing, yet these viral vectors are marred by significant safety concerns. Non-viral vectors are preferred for gene therapy, despite lower transfection efficiencies, and possess many customizable attributes that are desirable for tissue engineering applications. However, there is no single non-viral gene delivery strategy that "fits-all" cell types and tissues. Thus, there is a compelling opportunity to examine different non-viral vectors, especially physical vectors, and compare their relative degrees of success. This review examines the advantages and disadvantages of physical non-viral methods (i.e., microinjection, ballistic gene delivery, electroporation, sonoporation, laser irradiation, magnetofection, and electric field-induced molecular vibration), with particular attention given to electroporation because of its versatility, with further special emphasis on Nucleofection™. In addition, attributes of cellular character that can be used to improve differentiation strategies are examined for tissue engineering applications. Ultimately, electroporation exhibits a high transfection efficiency in many cell types, which is highly desirable for tissue engineering applications, but electroporation and other physical non-viral gene delivery methods are still limited by poor cell viability. Overcoming the challenge of poor cell viability in highly efficient physical non-viral techniques is the key to using gene delivery to enhance tissue engineering applications.

Physical non-viral gene delivery methods for tissue engineering

Science.gov (United States)

Mellott, Adam J.; Forrest, M. Laird; Detamore, Michael S.

2016-01-01

The integration of gene therapy into tissue engineering to control differentiation and direct tissue formation is not a new concept; however, successful delivery of nucleic acids into primary cells, progenitor cells, and stem cells has proven exceptionally challenging. Viral vectors are generally highly effective at delivering nucleic acids to a variety of cell populations, both dividing and non-dividing, yet these viral vectors are marred by significant safety concerns. Non-viral vectors are preferred for gene therapy, despite lower transfection efficiencies, and possess many customizable attributes that are desirable for tissue engineering applications. However, there is no single non-viral gene delivery strategy that “fits-all” cell types and tissues. Thus, there is a compelling opportunity to examine different non-viral vectors, especially physical vectors, and compare their relative degrees of success. This review examines the advantages and disadvantages of physical non-viral methods (i.e., microinjection, ballistic gene delivery, electroporation, sonoporation, laser irradiation, magnetofection, and electric field-induced molecular vibration), with particular attention given to electroporation because of its versatility, with further special emphasis on Nucleofection™. In addition, attributes of cellular character that can be used to improve differentiation strategies are examined for tissue engineering applications. Ultimately, electroporation exhibits a high transfection efficiency in many cell types, which is highly desirable for tissue engineering applications, but electroporation and other physical non-viral gene delivery methods are still limited by poor cell viability. Overcoming the challenge of poor cell viability in highly efficient physical non-viral techniques is the key to using gene delivery to enhance tissue engineering applications. PMID:23099792

Value of Sharing: Viral Advertisement

OpenAIRE

Duygu Aydın; Aşina Gülerarslan; Süleyman Karaçor; Tarık Doğan

2013-01-01

Sharing motivations of viral advertisements by consumers and the impacts of these advertisements on the perceptions for brand will be questioned in this study. Three fundamental questions are answered in the study. These are advertisement watching and sharing motivations of individuals, criteria of liking viral advertisement and the impact of individual attitudes for viral advertisement on brand perception respectively. This study will be carried out via a viral advertise...

Viral Marketing and Academic Institution

OpenAIRE

Koktová, Silvie

2010-01-01

This bachelor thesis examines modern and constantly developing kind of internet marketing -- the so called viral marketing. It deals with its origin, principle, process, advantages and disadvantages, types of viral marketing and presumptions of creating successful viral campaign. The aim of the theoretical part is especially the understanding of viral marketing as one of the effective instruments of contemporary marketing. In this theoretical part the thesis also elaborates a marketing school...

In vitro effects of pomegranate juice and pomegranate polyphenols on foodborne viral surrogates.

Science.gov (United States)

Su, Xiaowei; Sangster, Mark Y; D'Souza, Doris H

2010-12-01

Pomegranate juice (PJ) has gained popularity because of its associated antioxidant, antimicrobial, anticancer, and anti-inflammatory properties. However, its effects against epidemiologically significant foodborne viruses have not been investigated. In the absence of culturable human noroviruses, feline calicivirus (FCV-F9), murine norovirus (MNV-1), and MS2 (ssRNA) bacteriophage were used as foodborne viral surrogates. The aim of this research was to study the effects of PJ and pomegranate polyphenols (PP) on foodborne viral infectivity. Viruses at high (∼ 7 log(10) PFU/mL) or low (∼ 5 log(10) PFU/mL) titers were mixed with equal volumes of PJ, 8, 16, and 32 mg/mL of PP, or water (control) and incubated for 1 h at room temperature. Viral infectivity after treatments was evaluated using standardized plaque assays. PJ decreased the titer of FCV-F9, MNV-1, and MS2 by 2.56, 1.32, and 0.32 log(10) PFU/mL, respectively, for low titers and 1.20, 0.06, and 0.63 log(10) PFU/mL, respectively, for high titers. Interestingly, FCV-F9 was undetectable after exposure to the three tested PP solutions using both low and high titers. MNV-1 at low initial titers was reduced by 1.30, 2.11, and 3.61 log(10) PFU/mL and at high initial titers by 1.56, 1.48, and 1.54 log(10) PFU/mL with 4, 8, and 16 mg/mL of PP treatment, respectively. MS2 at low initial titers was reduced by 0.41, 0.45, and 0.93 log(10) PFU/mL and at high initial titers by 0.32, 0.41, and 0.72 log(10) PFU/mL after 4, 8, and 16 mg/mL of PP treatment, respectively. PJ and PP resulted in titer reductions of foodborne virus surrogates after 1 h exposure, showing promise for use in hurdle technologies and/or for therapeutic or preventive use. To suggest the use of PJ and PP as natural remedies for foodborne viral illness prevention, their mechanism of action against viral infectivity needs to be further investigated.

Bovine viral diarrhea virus (BVDV) genetic diversity in Spain: A review

International Nuclear Information System (INIS)

Diéguez, F.J.; Cerviño, M.; Yus, E.

2017-01-01

Bovine viral diarrhea virus (BVDV), a member of the genus Pestivirus of the family Flaviviridae, causes significant losses in cattle farming worldwide because of reduced milk production, increased mortality of young animals and reproductive, respiratory and intestinal problems. The virus is characterized by an important genetic, and consequently antigenic and pathogenic diversity. Knowing the variability of viral strains present in a population provides valuable information, particularly relevant for control programs development, vaccination recommendations and even identification of likely infection sources. Such information is therefore important at both local and regional levels. This review focuses on the genetic diversity of BVDV isolates infecting cattle in Spain over the last years. According to the published data, the most prevalent BVDV group in Spain was 1b, and to a lesser extent 1d, 1e and 1f. Besides, BVDV-2 has also been found in Spain with several ratified isolates. The studies carried out in Spain also showed increased genetic heterogeneity of BVDV strains, possibly due to a more intensive use of analytical tools available, presenting studies with increasingly greater sample sizes.

Bovine viral diarrhea virus (BVDV) genetic diversity in Spain: A review

Energy Technology Data Exchange (ETDEWEB)

Diéguez, F.J.; Cerviño, M.; Yus, E.

2017-07-01

Bovine viral diarrhea virus (BVDV), a member of the genus Pestivirus of the family Flaviviridae, causes significant losses in cattle farming worldwide because of reduced milk production, increased mortality of young animals and reproductive, respiratory and intestinal problems. The virus is characterized by an important genetic, and consequently antigenic and pathogenic diversity. Knowing the variability of viral strains present in a population provides valuable information, particularly relevant for control programs development, vaccination recommendations and even identification of likely infection sources. Such information is therefore important at both local and regional levels. This review focuses on the genetic diversity of BVDV isolates infecting cattle in Spain over the last years. According to the published data, the most prevalent BVDV group in Spain was 1b, and to a lesser extent 1d, 1e and 1f. Besides, BVDV-2 has also been found in Spain with several ratified isolates. The studies carried out in Spain also showed increased genetic heterogeneity of BVDV strains, possibly due to a more intensive use of analytical tools available, presenting studies with increasingly greater sample sizes.

Viral MicroRNAs Repress the Cholesterol Pathway, and 25-Hydroxycholesterol Inhibits Infection.

Science.gov (United States)

Serquiña, Anna K P; Kambach, Diane M; Sarker, Ontara; Ziegelbauer, Joseph M

2017-07-11

From various screens, we found that Kaposi's sarcoma-associated herpesvirus (KSHV) viral microRNAs (miRNAs) target several enzymes in the mevalonate/cholesterol pathway. 3-Hydroxy-3-methylglutaryl-coenzyme A (CoA) synthase 1 (HMGCS1), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR [a rate-limiting step in the mevalonate pathway]), and farnesyl-diphosphate farnesyltransferase 1 (FDFT1 [a committed step in the cholesterol branch]) are repressed by multiple KSHV miRNAs. Transfection of viral miRNA mimics in primary endothelial cells (human umbilical vein endothelial cells [HUVECs]) is sufficient to reduce intracellular cholesterol levels; however, small interfering RNAs (siRNAs) targeting only HMGCS1 did not reduce cholesterol levels. This suggests that multiple targets are needed to perturb this tightly regulated pathway. We also report here that cholesterol levels were decreased in de novo -infected HUVECs after 7 days. This reduction is at least partially due to viral miRNAs, since the mutant form of KSHV lacking 10 of the 12 miRNA genes had increased cholesterol compared to wild-type infections. We hypothesized that KSHV is downregulating cholesterol to suppress the antiviral response by a modified form of cholesterol, 25-hydroxycholesterol (25HC). We found that the cholesterol 25-hydroxylase (CH25H) gene, which is responsible for generating 25HC, had increased expression in de novo -infected HUVECs but was strongly suppressed in long-term latently infected cell lines. We found that 25HC inhibits KSHV infection when added exogenously prior to de novo infection. In conclusion, we found that multiple KSHV viral miRNAs target enzymes in the mevalonate pathway to modulate cholesterol in infected cells during latency. This repression of cholesterol levels could potentially be beneficial to viral infection by decreasing the levels of 25HC. IMPORTANCE A subset of viruses express unique microRNAs (miRNAs), which act like cellular miRNAs to generally repress host gene

Visualization of Content Release from Cell Surface-Attached Single HIV-1 Particles Carrying an Extra-Viral Fluorescent pH-Sensor.

Science.gov (United States)

Sood, Chetan; Marin, Mariana; Mason, Caleb S; Melikyan, Gregory B

2016-01-01

HIV-1 fusion leading to productive entry has long been thought to occur at the plasma membrane. However, our previous single virus imaging data imply that, after Env engagement of CD4 and coreceptors at the cell surface, the virus enters into and fuses with intracellular compartments. We were unable to reliably detect viral fusion at the plasma membrane. Here, we implement a novel virus labeling strategy that biases towards detection of virus fusion that occurs in a pH-neutral environment-at the plasma membrane or, possibly, in early pH-neutral vesicles. Virus particles are co-labeled with an intra-viral content marker, which is released upon fusion, and an extra-viral pH sensor consisting of ecliptic pHluorin fused to the transmembrane domain of ICAM-1. This sensor fully quenches upon virus trafficking to a mildly acidic compartment, thus precluding subsequent detection of viral content release. As an interesting secondary observation, the incorporation of the pH-sensor revealed that HIV-1 particles occasionally shuttle between neutral and acidic compartments in target cells expressing CD4, suggesting a small fraction of viral particles is recycled to the plasma membrane and re-internalized. By imaging viruses bound to living cells, we found that HIV-1 content release in neutral-pH environment was a rare event (~0.4% particles). Surprisingly, viral content release was not significantly reduced by fusion inhibitors, implying that content release was due to spontaneous formation of viral membrane defects occurring at the cell surface. We did not measure a significant occurrence of HIV-1 fusion at neutral pH above this defect-mediated background loss of content, suggesting that the pH sensor may destabilize the membrane of the HIV-1 pseudovirus and, thus, preclude reliable detection of single virus fusion events at neutral pH.

Visualization of Content Release from Cell Surface-Attached Single HIV-1 Particles Carrying an Extra-Viral Fluorescent pH-Sensor.

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Chetan Sood

Full Text Available HIV-1 fusion leading to productive entry has long been thought to occur at the plasma membrane. However, our previous single virus imaging data imply that, after Env engagement of CD4 and coreceptors at the cell surface, the virus enters into and fuses with intracellular compartments. We were unable to reliably detect viral fusion at the plasma membrane. Here, we implement a novel virus labeling strategy that biases towards detection of virus fusion that occurs in a pH-neutral environment-at the plasma membrane or, possibly, in early pH-neutral vesicles. Virus particles are co-labeled with an intra-viral content marker, which is released upon fusion, and an extra-viral pH sensor consisting of ecliptic pHluorin fused to the transmembrane domain of ICAM-1. This sensor fully quenches upon virus trafficking to a mildly acidic compartment, thus precluding subsequent detection of viral content release. As an interesting secondary observation, the incorporation of the pH-sensor revealed that HIV-1 particles occasionally shuttle between neutral and acidic compartments in target cells expressing CD4, suggesting a small fraction of viral particles is recycled to the plasma membrane and re-internalized. By imaging viruses bound to living cells, we found that HIV-1 content release in neutral-pH environment was a rare event (~0.4% particles. Surprisingly, viral content release was not significantly reduced by fusion inhibitors, implying that content release was due to spontaneous formation of viral membrane defects occurring at the cell surface. We did not measure a significant occurrence of HIV-1 fusion at neutral pH above this defect-mediated background loss of content, suggesting that the pH sensor may destabilize the membrane of the HIV-1 pseudovirus and, thus, preclude reliable detection of single virus fusion events at neutral pH.

[Emergent viral infections

NARCIS (Netherlands)

Galama, J.M.D.

2001-01-01

The emergence and re-emergence of viral infections is an ongoing process. Large-scale vaccination programmes led to the eradication or control of some viral infections in the last century, but new viruses are always emerging. Increased travel is leading to a rise in the importation of exotic

Synaptogyrin-2 Promotes Replication of a Novel Tick-borne Bunyavirus through Interacting with Viral Nonstructural Protein NSs.

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Sun, Qiyu; Qi, Xian; Zhang, Yan; Wu, Xiaodong; Liang, Mifang; Li, Chuan; Li, Dexin; Cardona, Carol J; Xing, Zheng

2016-07-29

Synaptogyrin-2 is a non-neuronal member of the synaptogyrin family involved in synaptic vesicle biogenesis and trafficking. Little is known about the function of synaptogyrin-2. Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease characterized by high fever, thrombocytopenia, and leukocytopenia with high mortality, caused by a novel tick-borne phlebovirus in the family Bunyaviridae. Our previous studies have shown that the viral nonstructural protein NSs forms inclusion bodies (IBs) that are involved in viral immune evasion, as well as viral RNA replication. In this study, we sought to elucidate the mechanism by which NSs formed the IBs, a lipid droplet-based structure confirmed by NSs co-localization with perilipin A and adipose differentiation-related protein (ADRP). Through a high throughput screening, we identified synaptogyrin-2 to be highly up-regulated in response to SFTS bunyavirus (SFTSV) infection and to be a promoter of viral replication. We demonstrated that synaptogyrin-2 interacted with NSs and was translocated into the IBs, which were reconstructed from lipid droplets into large structures in infection. Viral RNA replication decreased, and infectious virus titers were lowered significantly when synaptogyrin-2 was silenced in specific shRNA-expressing cells, which correlated with the reduced number of the large IBs restructured from regular lipid droplets. We hypothesize that synaptogyrin-2 is essential to promoting the formation of the IBs to become virus factories for viral RNA replication through its interaction with NSs. These findings unveil the function of synaptogyrin-2 as an enhancer in viral infection. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

THE ROLE OF INTERFERON ALPHA-2b IN REDUCING OF VIRAL LOAD IN HPV INFECTED WOMEN

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Кристина Владимировна Марочко

2017-05-01

Conclusion. Mono-infection was prevalent among HPV infected women HPV 16 is the most frequently detected hrHPV. The use of the drug interferon alfa-2b in the study group, contributed to viral load reduction.

Viral phenotype, antiretroviral resistance and clinical evolution in human immunodeficiency virus-infected children.

Science.gov (United States)

Mellado, M J; Cilleruelo, M J; Ortiz, M; Villota, J; García, M; Perez-Jurado, M L; Barreiro, G; Martín-Fontelos, P; Bernal, A

1997-11-01

The syncytium-inducing (SI) viral phenotype and the emergence of viral strains resistant to zidovudine have been described in persons infected with HIV, and in some cases they have been associated with poor prognosis. HIV isolates obtained from 37 HIV-infected children were analyzed to determine whether the SI viral phenotype and the mutation on the 215 position of the reverse transcriptase (M215) could be used as markers of disease progression. We performed peripheral blood coculture mononuclear cells, and we analyzed the induction of syncytia using the MT-2 cell line. The emergence of mutations on the 215 position was determined by PCR. We found a statistically significant association (P < 0.05) between SI viral phenotype and (1) recurrent serious bacterial infections, (2) absolute CD4+ cell counts <2 SD, (3) progression to AIDS and (4) death. Sixty percent of the children treated with zidovudine developed 215 mutant viral strains without statistically significant association with clinical or immunologic findings. The SI viral phenotype was statistically associated with the presence of the 215 mutation (P < 0.05). SI viral phenotype is a marker associated with a poor clinical and immunologic progression of the disease and it may facilitate the emergence of mutant strains in children treated with zidovudine.

NaVirCept - Nucleic Acid-Based Anti-Viral Project

International Nuclear Information System (INIS)

Stephen, E. R.; Wong, J.; Van Loon, D.

2007-01-01

Vaccines are generally considered to be the most effective countermeasures to bacterial and viral diseases, however, licensed vaccines against many disease agents are either not available or their efficacies have not been demonstrated. Vaccines are generally agent specific in terms of treatment spectrum and are subject to defeat through natural mutation or through directed efforts. With respect to viral therapeutics, one of the major limitations associated with antiviral drugs is acquired drug resistance caused by antigenic shift or drift. A number of next-generation prophylactic and/or therapeutic measures are on the horizon. Of these, nucleic acid-based drugs are showing great antiviral potential. These drugs elicit long-lasting, broad spectrum protective immune responses, especially to respiratory viral pathogens. The Nucleic Acid-Based Antiviral (NaVirCept) project provides the opportunity to demonstrate the effectiveness of novel medical countermeasures against military-significant endemic and other viral threat agents. This project expands existing DRDC drug delivery capability development, in the form of proprietary liposome intellectual property, by coupling it with leading-edge nucleic acid-based technology to deliver effective medical countermeasures that will protect deployed personnel and the warfighter against a spectrum of viral disease agents. The technology pathway will offer a means to combat emerging viral diseases or modified threat agents such as the bird flu or reconstructed Spanish flu without going down the laborious, time-consuming and expensive paths to develop countermeasures for each new and/or emerging viral disease organism.(author)

Biodegradable nanoparticle-entrapped vaccine induces cross-protective immune response against a virulent heterologous respiratory viral infection in pigs.

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Varun Dwivedi

Full Text Available Biodegradable nanoparticle-based vaccine development research is unexplored in large animals and humans. In this study, we illustrated the efficacy of nanoparticle-entrapped UV-killed virus vaccine against an economically important respiratory viral disease of pigs called porcine reproductive and respiratory syndrome virus (PRRSV. We entrapped PLGA [poly (lactide-co-glycolides] nanoparticles with killed PRRSV antigens (Nano-KAg and detected its phagocytosis by pig alveolar macrophages. Single doses of Nano-KAg vaccine administered intranasally to pigs upregulated innate and PRRSV specific adaptive responses. In a virulent heterologous PRRSV challenge study, Nano-KAg vaccine significantly reduced the lung pathology and viremia, and the viral load in the lungs. Immunologically, enhanced innate and adaptive immune cell population and associated cytokines with decreased secretion of immunosuppressive mediators were observed at both mucosal sites and blood. In summary, we demonstrated the benefits of intranasal delivery of nanoparticle-based viral vaccine in eliciting cross-protective immune response in pigs, a potential large animal model.

Viral Pneumonia in Patients with Hematologic Malignancy or Hematopoietic Stem Cell Transplantation.

Science.gov (United States)

Vakil, Erik; Evans, Scott E

2017-03-01

Viral pneumonias in patients with hematologic malignancies and recipients of hematopoietic stem cell transplantation cause significant morbidity and mortality. Advances in diagnostic techniques have enabled rapid identification of respiratory viral pathogens from upper and lower respiratory tract samples. Lymphopenia, myeloablative and T-cell depleting chemotherapy, graft-versus-host disease, and other factors increase the risk of developing life-threatening viral pneumonia. Chest imaging is often nonspecific but may aid in diagnoses. Bronchoscopy with bronchoalveolar lavage is recommended in those at high risk for viral pneumonia who have new infiltrates on chest imaging. Copyright © 2016 Elsevier Inc. All rights reserved.

Viral hepatitis A, B, and C: grown-up issues.

Science.gov (United States)

Sharapov, Umid M; Hu, Dale J

2010-08-01

Viral hepatitis is a major global health problem associated with significant morbidity and mortality. Although there are five major and distinct human hepatitis viruses characterized to date--referred to as hepatitis A, B, C, D, and E, respectively--only hepatitis A, B, and C are epidemiologically and clinically relevant for adolescents in North America. The clinical presentation of acute infection with each of these viruses is similar; thus, diagnosis depends on the use of specific serologic markers and viral nucleic acids. This review provides data on the epidemiology, clinical symptoms, diagnosis, treatment, and prevention of each of these three viral infections, along with points that are important or unique to adolescent patients.

Role of complement and antibodies in controlling infection with pathogenic simian immunodeficiency virus (SIV in macaques vaccinated with replication-deficient viral vectors

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Strasak Alexander

2009-06-01

Full Text Available Abstract Background We investigated the interplay between complement and antibodies upon priming with single-cycle replicating viral vectors (SCIV encoding SIV antigens combined with Adeno5-SIV or SCIV pseudotyped with murine leukemia virus envelope boosting strategies. The vaccine was applied via spray-immunization to the tonsils of rhesus macaques and compared with systemic regimens. Results Independent of the application regimen or route, viral loads were significantly reduced after challenge with SIVmac239 (p Conclusion The heterologous prime-boost strategy with replication-deficient viral vectors administered exclusively via the tonsils did not induce any neutralizing antibodies before challenge. However, after challenge, comparable SIV-specific humoral immune responses were observed in all vaccinated animals. Immunization with single cycle immunodeficiency viruses mounts humoral immune responses comparable to live-attenuated immunodeficiency virus vaccines.

A Functional Food Mixture “Protector” Reinforces the Protective Immune Parameters against Viral Flu Infection in Mice

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Kenza A. Mansoor

2018-06-01

Full Text Available Background: Viral influenza infection causes serious health issues especially when an outbreak occurs. Although influenza virus vaccines are available and each year manufactures modify the vaccine depending on the expected mutated strain, it is still far from satisfactory, mainly in young children and older adults. Therefore, a product that can support and shape the immune system to protect against viral flu infections is highly essential. Methods: A functional food water-soluble mixture of pomegranate, red grape, dates, olive fruit, figs, and ginger extracts, termed herein “Protector”, was prepared and tested in stimulating/modulating the production of specific cytokines, and hemagglutinin inhibition (HAI antibodies following viral flu vaccination in mice. Results: A single intraperitoneal or multiple oral administration for 1–7 days of “Protector” significantly increased the production of interferon (IFN-γ and interleukin (IL-12 in blood, spleen, and lungs of mice. When “Protector” was orally administered for one week following a single vaccine injection (primary immunization or for two weeks (one week apart following double vaccine injections (secondary immunization, mice significantly produced higher titers of HAI antibodies. This increase in HAI antibodies was associated with Pillow-inducing significant and different changes in vaccine-induced IFN-γ, IL-12, IL-6 and IL-22 following primary and secondary immunizations. Conclusions: “Protector” administration reinforces the protective immune parameters against viral flu infection. Therefore, after performing preclinical toxicology studies and ensuring its safety, “Protector” should be considered a potential product to be tested in clinical trials to conclude its efficacy in reducing the devastating effects of flu infection in humans and its outbreaks.

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

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...... opdrættet pighvar var patogene for pighvar. Helt (Coregonus lavaretus) er blevet mistænkt for at overføre VHSV til opdrættede fisk. For at undersøge dette blev 148 vilde helt fanget i Skjern Å i december, når helten svømmer opstrøms fra Ringkøbing Fjord for at gyde. Der blev ikke isoleret virus fra helt...

IL-4 and IL-13 mediated down-regulation of CD8 expression levels can dampen anti-viral CD8⁺ T cell avidity following HIV-1 recombinant pox viral vaccination.

Science.gov (United States)

Wijesundara, Danushka K; Jackson, Ronald J; Tscharke, David C; Ranasinghe, Charani

2013-09-23

We have shown that mucosal HIV-1 recombinant pox viral vaccination can induce high, avidity HIV-specific CD8(+) T cells with reduced interleukin (IL)-4 and IL-13 expression compared to, systemic vaccine delivery. In the current study how these cytokines act to regulate anti-viral CD8(+) T, cell avidity following HIV-1 recombinant pox viral prime-boost vaccination was investigated. Out of a panel of T cell avidity markers tested, only CD8 expression levels were found to be enhanced on, KdGag197-205 (HIV)-specific CD8(+) T cells obtained from IL-13(-/-), IL-4(-/-) and signal transducer and, activator of transcription of 6 (STAT6)(-/-) mice compared to wild-type (WT) controls following, vaccination. Elevated CD8 expression levels in this instance also correlated with polyfunctionality, (interferon (IFN)-γ, tumour necorsis factor (TNF)-α and IL-2 production) and the avidity of HIVspecific CD8(+) T cells. Furthermore, mucosal vaccination and vaccination with the novel adjuvanted IL-13 inhibitor (i.e. IL-13Rα2) vaccines significantly enhanced CD8 expression levels on HIV-specific CD8(+), T cells, which correlated with avidity. Using anti-CD8 antibodies that blocked CD8 availability on CD8(+), T cells, it was established that CD8 played an important role in increasing HIV-specific CD8(+) T cell avidity and polyfunctionality in IL-4(-/-), IL-13(-/-) and STAT6(-/-) mice compared to WT controls, following vaccination. Collectively, our data demonstrate that IL-4 and IL-13 dampen CD8 expression levels on anti-viral CD8(+) T cells, which can down-regulate anti-viral CD8(+) T cell avidity and, polyfunctionality following HIV-1 recombinant pox viral vaccination. These findings can be exploited to, design more efficacious vaccines not only against HIV-1, but many chronic infections where high, avidity CD8(+) T cells help protection. Copyright © 2013 Elsevier Ltd. All rights reserved.

Microneedle-mediated delivery of viral vectored vaccines.

Science.gov (United States)

Zaric, Marija; Ibarzo Yus, Bárbara; Kalcheva, Petya Petrova; Klavinskis, Linda Sylvia

2017-10-01

Microneedle array platforms are a promising technology for vaccine delivery, due to their ease of administration with no sharp waste generated, small size, possibility of targeted delivery to the specified skin depth and efficacious delivery of different vaccine formulations, including viral vectors. Areas covered: Attributes and challenges of the most promising viral vector candidates that have advanced to the clinic and that have been leveraged for skin delivery by microneedles; The importance of understanding the immunobiology of antigen-presenting cells in the skin, in particular dendritic cells, in order to generate further improved skin vaccination strategies; recent studies where viral vectors expressing various antigens have been coupled with microneedle technology to examine their potential for improved vaccination. Expert opinion: Simple, economic and efficacious vaccine delivery methods are needed to improve health outcomes and manage possible outbreaks of new emerging viruses. Understanding what innate/inflammatory signals are required to induce both immediate and long-term responses remains a major hurdle in the development of the effective vaccines. One approach to meet these needs is microneedle-mediated viral vector vaccination. In order for this technology to fulfil this potential the industry must invest significantly to further develop its design, production, biosafety, delivery and large-scale manufacturing.

DNA Damage Reduces the Quality, but Not the Quantity of Human Papillomavirus 16 E1 and E2 DNA Replication.

Science.gov (United States)

Bristol, Molly L; Wang, Xu; Smith, Nathan W; Son, Minkyeong P; Evans, Michael R; Morgan, Iain M

2016-06-22

Human papillomaviruses (HPVs) are causative agents in almost all cervical carcinomas. HPVs are also causative agents in head and neck cancer, the cases of which are increasing rapidly. Viral replication activates the DNA damage response (DDR) pathway; associated proteins are recruited to replication foci, and this pathway may serve to allow for viral genome amplification. Likewise, HPV genome double-strand breaks (DSBs) could be produced during replication and could lead to linearization and viral integration. Many studies have shown that viral integration into the host genome results in unregulated expression of the viral oncogenes, E6 and E7, promoting HPV-induced carcinogenesis. Previously, we have demonstrated that DNA-damaging agents, such as etoposide, or knocking down viral replication partner proteins, such as topoisomerase II β binding protein I (TopBP1), does not reduce the level of DNA replication. Here, we investigated whether these treatments alter the quality of DNA replication by HPV16 E1 and E2. We confirm that knockdown of TopBP1 or treatment with etoposide does not reduce total levels of E1/E2-mediated DNA replication; however, the quality of replication is significantly reduced. The results demonstrate that E1 and E2 continue to replicate under genomically-stressed conditions and that this replication is mutagenic. This mutagenesis would promote the formation of substrates for integration of the viral genome into that of the host, a hallmark of cervical cancer.

DNA Damage Reduces the Quality, but Not the Quantity of Human Papillomavirus 16 E1 and E2 DNA Replication

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Molly L. Bristol

2016-06-01

Full Text Available Human papillomaviruses (HPVs are causative agents in almost all cervical carcinomas. HPVs are also causative agents in head and neck cancer, the cases of which are increasing rapidly. Viral replication activates the DNA damage response (DDR pathway; associated proteins are recruited to replication foci, and this pathway may serve to allow for viral genome amplification. Likewise, HPV genome double-strand breaks (DSBs could be produced during replication and could lead to linearization and viral integration. Many studies have shown that viral integration into the host genome results in unregulated expression of the viral oncogenes, E6 and E7, promoting HPV-induced carcinogenesis. Previously, we have demonstrated that DNA-damaging agents, such as etoposide, or knocking down viral replication partner proteins, such as topoisomerase II β binding protein I (TopBP1, does not reduce the level of DNA replication. Here, we investigated whether these treatments alter the quality of DNA replication by HPV16 E1 and E2. We confirm that knockdown of TopBP1 or treatment with etoposide does not reduce total levels of E1/E2-mediated DNA replication; however, the quality of replication is significantly reduced. The results demonstrate that E1 and E2 continue to replicate under genomically-stressed conditions and that this replication is mutagenic. This mutagenesis would promote the formation of substrates for integration of the viral genome into that of the host, a hallmark of cervical cancer.

Laboratory procedures to generate viral metagenomes.

Science.gov (United States)

Thurber, Rebecca V; Haynes, Matthew; Breitbart, Mya; Wegley, Linda; Rohwer, Forest

2009-01-01

This collection of laboratory protocols describes the steps to collect viruses from various samples with the specific aim of generating viral metagenome sequence libraries (viromes). Viral metagenomics, the study of uncultured viral nucleic acid sequences from different biomes, relies on several concentration, purification, extraction, sequencing and heuristic bioinformatic methods. No single technique can provide an all-inclusive approach, and therefore the protocols presented here will be discussed in terms of hypothetical projects. However, care must be taken to individualize each step depending on the source and type of viral-particles. This protocol is a description of the processes we have successfully used to: (i) concentrate viral particles from various types of samples, (ii) eliminate contaminating cells and free nucleic acids and (iii) extract, amplify and purify viral nucleic acids. Overall, a sample can be processed to isolate viral nucleic acids suitable for high-throughput sequencing in approximately 1 week.

Hepatitis A through E (Viral Hepatitis)

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... Treatment Eating, Diet, & Nutrition Clinical Trials Wilson Disease Hepatitis (Viral) View or Print All Sections What is Viral Hepatitis? Viral hepatitis is an infection that causes liver inflammation ...

Importance of viral diseases in irradiated persons

International Nuclear Information System (INIS)

Blaha, M.; Jebavy, L.; Merka, V.; Horacek, J.

1988-01-01

A preliminary study was performed aimed at establishing the incidence of some viral diseases in radiation syndrome patients and the significance of the diseases for prognosis. In the study, 77 patients with syndromologically identical acute hematological forms of radiation sickness, mainly leukemic patients suffering from severe blood formation suppression and/or hematoblastosis were examined for concurrent herpes simplex virus and cytomegalovirus infections. Active viruses were isolated in almost 30% of the patients; nearly 90% of the patients were serologically positive, shedding antibodies. The findings thus confirmed the view that viral disease, especially in immunocompromised patients, has a critical effect on the survival of radiation sickness sufferers. (L.O.). 12 refs

Adsorption of viral particles from the blood plasma of patients with viral hepatitis on nanodiamonds.

Science.gov (United States)

Baron, A V; Osipov, N V; Yashchenko, S V; Kokotukha, Yu A; Baron, I J; Puzyr, A P; Olkhovskiy, I A; Bondar, V S

2016-07-01

Adsorption of viral particles from the blood plasma of patients with viral hepatitis B and C on modified nanodiamonds (MNDs) was shown in the in vitro experiments. PCR method showed the treatment of plasma with MNDs leads to a decrease in the viral load by 2-3 orders of magnitude or more in both cases studied. These results make it possible to predict the applicability of MNDs for the development of new technologies of hemodialysis and plasmapheresis for binding and removal of viral particles from the blood of infected patients.

Phosphorylation of human respiratory syncytial virus P protein at serine 54 regulates viral uncoating

International Nuclear Information System (INIS)

Asenjo, Ana; Gonzalez-Armas, Juan C.; Villanueva, Nieves

2008-01-01

The human respiratory syncytial virus (HRSV) structural P protein, phosphorylated at serine (S) and threonine (T) residues, is a co-factor of viral RNA polymerase. The phosphorylation of S54 is controlled by the coordinated action of two cellular enzymes: a lithium-sensitive kinase, probably glycogen synthetase kinase (GSK-3) β and protein phosphatase 2A (PP2A). Inhibition of lithium-sensitive kinase, soon after infection, blocks the viral growth cycle by inhibiting synthesis and/or accumulation of viral RNAs, proteins and extracellular particles. P protein phosphorylation at S54 is required to liberate viral ribonucleoproteins (RNPs) from M protein, during the uncoating process. Kinase inhibition, late in infection, produces a decrease in genomic RNA and infectious viral particles. LiCl, intranasally applied to mice infected with HRSV A2 strain, reduces the number of mice with virus in their lungs and the virus titre. Administration of LiCl to humans via aerosol should prevent HRSV infection, without secondary effects

Efficacy of VIFERON® in the combination therapy of viral encephalitis in infants

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N. V. Skripchenko

2015-01-01

Full Text Available The paper provides the clinical and ettological characteristics of viral encephalitis in 103 children aged 1 month to 3 years and the results of a comparative study of the efficiency of recombinant interferon-a 2b (VIFERON® as rectal suppositories incorporated into the combination therapy of the disease. The VIFERON® regimen and duration in the study were determined by the pattern of encephalitis. In the acute course of the latter, VIFERON® was given twice daily for 14 days; in its protracted or chronical course, the drug was used twice daily for 14 days, then thrice daily for 1 and 3 months, respectively. The administration of VIFERON® in viral encephalitis was established to accelerate sanogenetic processes and to reduce the time of progression and preservation of major extracerebral and cerebral symptoms and the length of sanitization of cerebrospinal fluid (CSF and viremia. The use of VIFERON® resulted in better disease outcomes, prevented deaths, decreased the rate of an autonomic state from 8 to 1,8%, increased recovery rates without defects from 22 to 51%, and reduced the rate of cystic and gliotic changes in the brain by 2,1 times. Slower CSF sanitization and longer viremia were ascertained in children with chronic and protracted viral encephalitis, which necessitated the longer administration of VIFERON®. Incorporation of recombinant interferon-a 2b into the therapy of viral encephalitis in infants ensures higher serum concentrations of interferon-a and helps keep compensatory capacities for its production, leading to the promptest recovery. The findings suggest that the incorporation of VIFERON® as rectal suppositories into the therapy of viral encephalitis is effective and safe in infants.

Faktor Risiko Non Viral Pada Karsinoma Nasofaring

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Sukri Rahman

2015-09-01

Full Text Available Abstrak           Latar belakang: Karsinoma nasofaring adalah tumor ganas epitel nasofaring yang sampai saat ini penyebabnya belum diketahui, infeksi virus Epstein Barr dilaporkan sebagai faktor dominan terjadinya karsinoma nasofaring tetapi faktor non viral juga berperan untuk timbulnya keganasan nasofaring. Tujuan: Untuk mengetahui faktor non viral  yang dapat meningkatkan kejadian karsinoma nasofaring sehingga dapat mencegah dan menghindari faktor-faktor non viral tersebut. Tinjauan Pustaka: Karsinoma nasofaring merupakan tumor ganas epitel nasofaring yang penyebabnya berhubungan dengan faktor viral dan non viral diantaranya asap rokok, ikan asin, formaldehid, genetik, asap kayu bakar , debu kayu, infeksi kronik telinga hidung tenggorok, alkohol dan obat tradisional. Kesimpulan: Pembuktian secara klinis dan ilmiah terhadap faktor non viral sebagai penyebab timbulnya karsinoma nasofaring masih belum dapat dijelaskan secara pasti. Faktor non viral merupakan salah satu faktor risiko yang dapat meningkatkan angka kejadian timbulnya keganasan nasofaring Kata kunci: karsinoma nasofaring, faktor risiko, non viral AbstractBackground: Nasopharyngeal carcinoma is a malignant epithelial nasopharyngeal tumor that until now the cause still unknown, Epstein barr virus infection had reported as predominant occurance of nasopharyngeal carcinoma but non viral factors may also contribute to the onset of the incidence of nasopharyngeal malignancy. Purpose: To find non viral factors that may increase the incidence of nasopharyngel carcinoma in order to prevent and avoid non-viral factors Literature: Nasopharyngeal carcinoma is a malignant tumor that causes nasopharyngeal epithelium associated with viral and non-viral factors such as cigarette smoke, salt fish, formaldehyde, genetic, wood smoke ,wood dust, ear nose throat chronic infections, alcohol, and traditional medicine. Conclusion: Clinically and scientifically proving the non-viral factors as

A viral metagenomic approach on a nonmetagenomic experiment

DEFF Research Database (Denmark)

Bovo, Samuele; Mazzoni, Gianluca; Ribani, Anisa

2017-01-01

Shot-gun next generation sequencing (NGS) on whole DNA extracted from specimens collected from mammals often produces reads that are not mapped (i.e. unmapped reads) on the host reference genome and that are usually discarded as by-products of the experiments. In this study, we mined Ion Torrent...... reads obtained by sequencing DNA isolated from archived blood samples collected from 100 performance tested Italian Large White pigs. Two reduced representation libraries were prepared from two DNA pools constructed each from 50 equimolar DNA samples. Bioinformatic analyses were carried out to mine...... unmapped reads on the reference pig genome that were obtained from the two NGS datasets. In silico analyses included read mapping and sequence assembly approaches for a viral metagenomic analysis using the NCBI Viral Genome Resource. Our approach identified sequences matching several viruses...

Metabolism goes viral.

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Miyake-Stoner, Shigeki J; O'Shea, Clodagh C

2014-04-01

Viral and cellular oncogenes converge in targeting critical protein interaction networks to reprogram the cellular DNA and protein replication machinery for pathological replication. In this issue, Thai et al. (2014) show that adenovirus E4ORF1 activates MYC glycolytic targets to induce a Warburg-like effect that converts glucose into nucleotides for viral replication. Copyright © 2014 Elsevier Inc. All rights reserved.

Viral tRNA Mimicry from a Biocommunicative Perspective

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Ascensión Ariza-Mateos

2017-12-01

Full Text Available RNA viruses have very small genomes which limits the functions they can encode. One of the strategies employed by these viruses is to mimic key factors of the host cell so they can take advantage of the interactions and activities these factors typically participate in. The viral RNA genome itself was first observed to mimic cellular tRNA over 40 years ago. Since then researchers have confirmed that distinct families of RNA viruses are accessible to a battery of cellular factors involved in tRNA-related activities. Recently, potential tRNA-like structures have been detected within the sequences of a 100 mRNAs taken from human cells, one of these being the host defense interferon-alpha mRNA; these are then additional to the examples found in bacterial and yeast mRNAs. The mimetic relationship between tRNA, cellular mRNA, and viral RNA is the central focus of two considerations described below. These are subsequently used as a preface for a final hypothesis drawing on concepts relating to mimicry from the social sciences and humanities, such as power relations and creativity. Firstly, the presence of tRNA-like structures in mRNAs indicates that the viral tRNA-like signal could be mimicking tRNA-like elements that are contextualized by the specific carrier mRNAs, rather than, or in addition to, the tRNA itself, which would significantly increase the number of potential semiotic relations mediated by the viral signals. Secondly, and in particular, mimicking a host defense mRNA could be considered a potential new viral strategy for survival. Finally, we propose that mRNA’s mimicry of tRNA could be indicative of an ancestral intracellular conflict in which species of mRNAs invaded the cell, but from within. As the meaning of the mimetic signal depends on the context, in this case, the conflict that arises when the viral signal enters the cell can change the meaning of the mRNAs’ internal tRNA-like signals, from their current significance to that

Viral findings in adult hematological patients with neutropenia.

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Lars Ohrmalm

Full Text Available BACKGROUND: Until recently, viral infections in patients with hematological malignancies were concerns primarily in allogeneic hematopoietic stem cell transplant (HSCT recipients. During the last years, changed treatment regimens for non-transplanted patients with hematological malignancies have had potential to increase the incidence of viral infections in this group. In this study, we have prospectively investigated the prevalence of a broad range of respiratory viruses in nasopharyngeal aspirate (NPA as well as viruses that commonly reactivate after allogeneic HSCT. METHODOLOGY/PRINCIPAL FINDINGS: Patients with hematological malignancies and therapy induced neutropenia (n = 159 were screened regarding a broad range of common respiratory viruses in the nasopharynx and for viruses commonly detected in severely immunosuppressed patients in peripheral blood. Quantitative PCR was used for detection of viruses. A viral pathogen was detected in 35% of the patients. The detection rate was rather similar in blood (22% and NPA (18% with polyoma BK virus and rhinovirus as dominating pathogens in blood and NPA, respectively. Patients with chronic lymphocytic leukemia (CLL (p<0.01 and patients with fever (p<0.001 were overrepresented in the virus-positive group. Furthermore, viral findings in NPA were associated with upper respiratory symptoms (URTS (p<0.0001. CONCLUSIONS/SIGNIFICANCE: Both respiratory viral infections and low titers of viruses in blood from patients with neutropenia were common. Patients with CLL and patients with fever were independently associated to these infections, and viral findings in NPA were associated to URTS indicating active infection. These findings motivate further studies on viruses' impact on this patient category and their potential role as causative agents of fever during neutropenia.

Dengue virus genomic variation associated with mosquito adaptation defines the pattern of viral non-coding RNAs and fitness in human cells.

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Claudia V Filomatori

2017-03-01

Full Text Available The Flavivirus genus includes a large number of medically relevant pathogens that cycle between humans and arthropods. This host alternation imposes a selective pressure on the viral population. Here, we found that dengue virus, the most important viral human pathogen transmitted by insects, evolved a mechanism to differentially regulate the production of viral non-coding RNAs in mosquitos and humans, with a significant impact on viral fitness in each host. Flavivirus infections accumulate non-coding RNAs derived from the viral 3'UTRs (known as sfRNAs, relevant in viral pathogenesis and immune evasion. We found that dengue virus host adaptation leads to the accumulation of different species of sfRNAs in vertebrate and invertebrate cells. This process does not depend on differences in the host machinery; but it was found to be dependent on the selection of specific mutations in the viral 3'UTR. Dissecting the viral population and studying phenotypes of cloned variants, the molecular determinants for the switch in the sfRNA pattern during host change were mapped to a single RNA structure. Point mutations selected in mosquito cells were sufficient to change the pattern of sfRNAs, induce higher type I interferon responses and reduce viral fitness in human cells, explaining the rapid clearance of certain viral variants after host change. In addition, using epidemic and pre-epidemic Zika viruses, similar patterns of sfRNAs were observed in mosquito and human infected cells, but they were different from those observed during dengue virus infections, indicating that distinct selective pressures act on the 3'UTR of these closely related viruses. In summary, we present a novel mechanism by which dengue virus evolved an RNA structure that is under strong selective pressure in the two hosts, as regulator of non-coding RNA accumulation and viral fitness. This work provides new ideas about the impact of host adaptation on the variability and evolution of

Zika Fetal Neuropathogenesis: Etiology of a Viral Syndrome.

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Zachary A Klase

2016-08-01

Full Text Available The ongoing Zika virus epidemic in the Americas and the observed association with both fetal abnormalities (primary microcephaly and adult autoimmune pathology (Guillain-Barré syndrome has brought attention to this neglected pathogen. While initial case studies generated significant interest in the Zika virus outbreak, larger prospective epidemiology and basic virology studies examining the mechanisms of Zika viral infection and associated pathophysiology are only now starting to be published. In this review, we analyze Zika fetal neuropathogenesis from a comparative pathology perspective, using the historic metaphor of "TORCH" viral pathogenesis to provide context. By drawing parallels to other viral infections of the fetus, we identify common themes and mechanisms that may illuminate the observed pathology. The existing data on the susceptibility of various cells to both Zika and other flavivirus infections are summarized. Finally, we highlight relevant aspects of the known molecular mechanisms of flavivirus replication.

Zika Fetal Neuropathogenesis: Etiology of a Viral Syndrome

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Klase, Zachary A.; Khakhina, Svetlana; Schneider, Adriano De Bernardi; Callahan, Michael V.; Glasspool-Malone, Jill

2016-01-01

The ongoing Zika virus epidemic in the Americas and the observed association with both fetal abnormalities (primary microcephaly) and adult autoimmune pathology (Guillain–Barré syndrome) has brought attention to this neglected pathogen. While initial case studies generated significant interest in the Zika virus outbreak, larger prospective epidemiology and basic virology studies examining the mechanisms of Zika viral infection and associated pathophysiology are only now starting to be published. In this review, we analyze Zika fetal neuropathogenesis from a comparative pathology perspective, using the historic metaphor of “TORCH” viral pathogenesis to provide context. By drawing parallels to other viral infections of the fetus, we identify common themes and mechanisms that may illuminate the observed pathology. The existing data on the susceptibility of various cells to both Zika and other flavivirus infections are summarized. Finally, we highlight relevant aspects of the known molecular mechanisms of flavivirus replication. PMID:27560129

Bovine viral diarrhea virus (BVDV genetic diversity in Spain: A review

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Francisco J. Diéguez

2017-07-01

Full Text Available Bovine viral diarrhea virus (BVDV, a member of the genus Pestivirus of the family Flaviviridae, causes significant losses in cattle farming worldwide because of reduced milk production, increased mortality of young animals and reproductive, respiratory and intestinal problems. The virus is characterized by an important genetic, and consequently antigenic and pathogenic diversity. Knowing the variability of viral strains present in a population provides valuable information, particularly relevant for control programs development, vaccination recommendations and even identification of likely infection sources. Such information is therefore important at both local and regional levels. This review focuses on the genetic diversity of BVDV isolates infecting cattle in Spain over the last years. According to the published data, the most prevalent BVDV group in Spain was 1b, and to a lesser extent 1d, 1e and 1f. Besides, BVDV-2 has also been found in Spain with several ratified isolates. The studies carried out in Spain also showed increased genetic heterogeneity of BVDV strains, possibly due to a more intensive use of analytical tools available, presenting studies with increasingly greater sample sizes.

Immunological and molecular epidemiological characteristics of acute and fulminant viral hepatitis A.

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Hussain, Zahid; Husain, Syed A; Almajhdi, Fahad N; Kar, Premashis

2011-05-23

Hepatitis A virus is an infection of liver; it is hyperendemic in vast areas of the world including India. In most cases it causes an acute self limited illness but rarely fulminant. There is growing concern about change in pattern from asymptomatic childhood infection to an increased incidence of symptomatic disease in the adult population. In-depth analysis of immunological, viral quantification and genotype of acute and fulminant hepatitis A virus. Serum samples obtained from 1009 cases of suspected acute viral hepatitis was employed for different biochemical and serological examination. RNA was extracted from blood serum, reverse transcribed into cDNA and amplified using nested PCR for viral quantification, sequencing and genotyping. Immunological cell count from freshly collected whole blood was carried out by fluorescence activated cell sorter. Fulminant hepatitis A was mostly detected with other hepatic viruses. CD8+ T cells count increases in fulminant hepatitis to a significantly high level (P = 0.005) compared to normal healthy control. The immunological helper/suppressor (CD4+/CD8+) ratio of fulminant hepatitis was significantly lower compared to acute cases. The serologically positive patients were confirmed by RT-PCR and total of 72 (69.2%) were quantified and sequenced. The average quantitative viral load of fulminant cases was significantly higher (P viral load defines the severity of the fulminant hepatitis A. Phylogenetic analysis of acute and fulminant hepatitis A confirmed genotypes IIIA as predominant against IA with no preference of disease severity.

The epidemiology of viral hepatitis in Qatar

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Bener Abdulbari

2009-01-01

Full Text Available Viral hepatitis is a major public health problem in many countries all over the world and especially in Middle East, Asia, East-Europe, and Africa. The aim of our study was to assess the incidence of viral hepatitis A, B and C in Qatar and compare it with other countries. This is a retrospective cohort study, which was conducted at Hamad General Hospital, State of Qatar from 2002-2006. Patients who were screened and diagnosed with viral hepatitis were included in this study. The diagnostic classification of definite viral hepatitis was made in accordance with criteria based on the International Classification of Disease tenth revision (ICD-10. A total of 527 cases of hepatitis C, 396 cases of hepatitis B, 162 cases of hepatitis A and 108 cases of unspecified were reported during the year 2006. Reported incidence rate per 10,000 populations during the year 2006 for hepatitis A was 1.9, hepatitis B 4.7, and Hepatitis C 6.3. The proportion of hepatitis B and C was significantly higher in male population than females across the years (2002-2006. Hepatitis A was more prevalent in children below 15 years (72.3%, hepatitis B in adults aged above 15 years, and hepatitis C in the population above 35 years of age. The incidence of hepatitis A has been declining in Qataris and increasing in expatriates. There was a significant relationship in gender and age group of the patients with hepatitis A, B and C. We conclude that hepatitis has become a national health issue in Qatar. The incidence rate of hepatitis in Qatar is comparable to its neighboring countries, United Arab Emirates and Saudi Arabia. There is a need for further research on hepatitis and the associated risk factors.

Exercise Improves Host Response to Influenza Viral Infection in Obese and Non-Obese Mice through Different Mechanisms

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Warren, Kristi J.; Olson, Molly M.; Thompson, Nicholas J.; Cahill, Mackenzie L.; Wyatt, Todd A.; Yoon, Kyoungjin J.; Loiacono, Christina M.; Kohut, Marian L.

2015-01-01

Obesity has been associated with greater severity of influenza virus infection and impaired host defense. Exercise may confer health benefits even when weight loss is not achieved, but it has not been determined if regular exercise improves immune defense against influenza A virus (IAV) in the obese condition. In this study, diet-induced obese mice and lean control mice exercised for eight weeks followed by influenza viral infection. Exercise reduced disease severity in both obese and non-obese mice, but the mechanisms differed. Exercise reversed the obesity-associated delay in bronchoalveolar-lavage (BAL) cell infiltration, restored BAL cytokine and chemokine production, and increased ciliary beat frequency and IFNα-related gene expression. In non-obese mice, exercise treatment reduced lung viral load, increased Type-I-IFN-related gene expression early during infection, but reduced BAL inflammatory cytokines and chemokines. In both obese and non-obese mice, exercise increased serum anti-influenza virus specific IgG2c antibody, increased CD8+ T cell percentage in BAL, and reduced TNFα by influenza viral NP-peptide-responding CD8+ T cells. Overall, the results suggest that exercise “restores” the immune response of obese mice to a phenotype similar to non-obese mice by improving the delay in immune activation. In contrast, in non-obese mice exercise treatment results in an early reduction in lung viral load and limited inflammatory response. PMID:26110868

Covariation of viral parameters with bacterial assemblage richness and diversity in the water column and sediments

Science.gov (United States)

Hewson, Ian; Fuhrman, Jed A.

2007-05-01

Viruses are hypothesized to maintain diversity in microbial assemblages by regulating the abundance of dominant competitors and thereby allowing less-dominant competitors to persist in assemblages; however, there have been few empirical data sets to support this idea. In this study, we examined the relationship between the ratio of viral abundance to bacterial abundance, viral production, and the relative richness and diversity of bacterial assemblage fingerprints, in samples taken from geographically widespread locations (North Pacific gyre, the Amazon River plume and adjacent North Atlantic gyre, Gulf of Mexico, Southern California Bight and Arafura—Coral Seas) which are oligo- to mesotrophic. Bacterial assemblage richness and diversity as measured by automated rRNA intergenic spacer (ARISA) fingerprinting were significantly and positively correlated with the ratio of virus abundance to bacteria abundance (VBR) and to the rate of virus production only in the oligotrophic North Pacific gyre. ARISA fingerprint richness/diversity were not significantly correlated to viral parameters when assessed across all samples in surface waters, suggesting there is not a singular global quantitative relationship between viral pressure and host diversity within well evolved host/virus systems in different geographic locations in plankton. In sediments off Southern California, viral parameters significantly and negatively correlated with ARISA diversity, suggesting strong viral interactions in this habitat. To examine covariation of viral parameters and the relative abundance and diversity of rarer bacterial taxa (i.e., less-dominant competitor), the richness and diversity of diazotroph communities was measured using terminal restriction fragment length polymorphism (TRFLP) of a portion ( nifH) of the nitrogenase gene. The richness and diversity of diazotrophic communities were significantly and negatively correlated with viral parameters across all locations. Since diazotrophs

Dynamics of HPV viral loads reflect the treatment effect of photodynamic therapy in genital warts.

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Hu, Zhili; Liu, Lishi; Zhang, Wenjing; Liu, Hui; Li, Junpeng; Jiang, Lifen; Zeng, Kang

2018-03-01

Photodynamic therapy (PDT) has demonstrated good clinical cure rates and low recurrence rates in the treatment of genital warts. Human papillomavirus (HPV) genotypes and viral load assays can reflect the status of persistent or latent infection and serve as a predictor of infection clearance. Specimens from 41 patients with HPV infection were obtained, and the HPV genotypes and viral load were analyzed using real-time polymerase chain reaction (PCR) assays. Traditional treatment, such as radiofrequency, microwave, or surgical therapy, was used to remove the visible lesions, and then PDT treatment was performed every week. HPV DNA testing was performed at every patient visit and the frequency of PDT treatment was determined by changes in HPV viral loads. HPV viral loads decreased significantly after PDT treatment. There were significant differences in HPV viral loads between pretherapy and three or six rounds of PDT treatment. Significant differences were also observed between single and multiple type HPV infection after six rounds of PDT treatment. Patients with single type HPV infection had significantly higher rates of negative HPV DNA test results, as compared with patients with multiple infections after six rounds of PDT treatment; however, there was no difference in recurrence rates between the two groups. Dynamic monitoring of HPV genotypes and viral loads can be used to guide PDT treatment and indicate PDT treatment efficacy in eliminating HPV. Copyright © 2017 Elsevier B.V. All rights reserved.

Viral kinetics of Enterovirus 71 in human abdomyosarcoma cells

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Lu, Jing; He, Ya-Qing; Yi, Li-Na; Zan, Hong; Kung, Hsiang-Fu; He, Ming-Liang

2011-01-01

AIM: To characterise the viral kinetics of enterovirus 71 (EV71). METHODS: In this study, human rhabdomyosarcoma (RD) cells were infected with EV71 at different multiplicity of infection (MOI). After infection, the cytopathic effect (CPE) was monitored and recorded using a phase contrast microscope associated with a CCD camera at different time points post viral infection (0, 6, 12, 24 h post infection). Cell growth and viability were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in both EV71 infected and mock infected cells at each time point. EV71 replication kinetics in RD cells was determined by measuring the total intracellular viral RNA with real-time reverse-transcription polymerase chain reaction (qRT-PCR). Also, the intracellular and extracellular virion RNA was isolated and quantified at different time points to analyze the viral package and secretion. The expression of viral protein was determined by analyze the levels of viral structure protein VP1 with Western blotting. RESULTS: EV71 infection induced a significant CPE as early as 6 h post infection (p.i.) in both RD cells infected with high ratio of virus (MOI 10) and low ratio of virus (MOI 1). In EV71 infected cells, the cell growth was inhibited and the number of viable cells was rapidly decreased in the later phase of infection. EV71 virions were uncoated immediately after entry. The intracellular viral RNA began to increase at as early as 3 h p.i. and the exponential increase was found between 3 h to 6 h p.i. in both infected groups. For viral structure protein synthesis, results from western-blot showed that intracellular viral protein VP1 could not be detected until 6 h p.i. in the cells infected at either MOI 1 or MOI 10; and reached the peak at 9 h p.i. in the cells infected with EV71 at both MOI 1 and MOI 10. Simultaneously, the viral package and secretion were also actively processed as the virus underwent rapid replication. The viral package kinetics

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....

Assembly of viral genomes from metagenomes

NARCIS (Netherlands)

S.L. Smits (Saskia); R. Bodewes (Rogier); A. Ruiz-Gonzalez (Aritz); V. Baumgärtner (Volkmar); M.P.G. Koopmans D.V.M. (Marion); A.D.M.E. Osterhaus (Albert); A. Schürch (Anita)

2014-01-01

textabstractViral infections remain a serious global health issue. Metagenomic approaches are increasingly used in the detection of novel viral pathogens but also to generate complete genomes of uncultivated viruses. In silico identification of complete viral genomes from sequence data would allow

Viral commercials: the consumer as marketeer

NARCIS (Netherlands)

Ketelaar, P.E.; Lucassen, P.; Kregting, G.H.J.

2010-01-01

Research into the reasons why consumers pass along viral commercials: their motives, the content characteristics of viral commercials and the medium context in which viral commercials appear. Based on the uses and gratifications perspective this study has determined which motives of consumers,

Viral Infection in Renal Transplant Recipients

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Jovana Cukuranovic

2012-01-01

Full Text Available Viruses are among the most common causes of opportunistic infection after transplantation. The risk for viral infection is a function of the specific virus encountered, the intensity of immune suppression used to prevent graft rejection, and other host factors governing susceptibility. Although cytomegalovirus is the most common opportunistic pathogen seen in transplant recipients, numerous other viruses have also affected outcomes. In some cases, preventive measures such as pretransplant screening, prophylactic antiviral therapy, or posttransplant viral monitoring may limit the impact of these infections. Recent advances in laboratory monitoring and antiviral therapy have improved outcomes. Studies of viral latency, reactivation, and the cellular effects of viral infection will provide clues for future strategies in prevention and treatment of viral infections. This paper will summarize the major viral infections seen following transplant and discuss strategies for prevention and management of these potential pathogens.

A method for quantifying mechanical properties of tissue following viral infection.

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Vy Lam

Full Text Available Viral infection and replication involves the reorganization of the actin network within the host cell. Actin plays a central role in the mechanical properties of cells. We have demonstrated a method to quantify changes in mechanical properties of fabricated model three-dimensional (3D connective tissue following viral infection. Using this method, we have characterized the impact of infection by the human herpesvirus, cytomegalovirus (HCMV. HCMV is a member of the herpesvirus family and infects a variety of cell types including fibroblasts. In the body, fibroblasts are necessary for maintaining connective tissue and function by creating mechanical force. Using this 3D connective tissue model, we observed that infection disrupted the cell's ability to generate force and reduced the cumulative contractile force of the tissue. The addition of HCMV viral particles in the absence of both viral gene expression and DNA replication was sufficient to disrupt tissue function. We observed that alterations of the mechanical properties are, in part, due to a disruption of the underlying complex actin microfilament network established by the embedded fibroblasts. Finally, we were able to prevent HCMV-mediated disruption of tissue function by the addition of human immune globulin against HCMV. This study demonstrates a method to quantify the impact of viral infection on mechanical properties which are not evident using conventional cell culture systems.

Viral Metagenomics: MetaView Software

Energy Technology Data Exchange (ETDEWEB)

Zhou, C; Smith, J

2007-10-22

The purpose of this report is to design and develop a tool for analysis of raw sequence read data from viral metagenomics experiments. The tool should compare read sequences of known viral nucleic acid sequence data and enable a user to attempt to determine, with some degree of confidence, what virus groups may be present in the sample. This project was conducted in two phases. In phase 1 we surveyed the literature and examined existing metagenomics tools to educate ourselves and to more precisely define the problem of analyzing raw read data from viral metagenomic experiments. In phase 2 we devised an approach and built a prototype code and database. This code takes viral metagenomic read data in fasta format as input and accesses all complete viral genomes from Kpath for sequence comparison. The system executes at the UNIX command line, producing output that is stored in an Oracle relational database. We provide here a description of the approach we came up with for handling un-assembled, short read data sets from viral metagenomics experiments. We include a discussion of the current MetaView code capabilities and additional functionality that we believe should be added, should additional funding be acquired to continue the work.

BRD4 is associated with raccoon polyomavirus genome and mediates viral gene transcription and maintenance of a stem cell state in neuroglial tumour cells.

Science.gov (United States)

Church, Molly E; Estrada, Marko; Leutenegger, Christian M; Dela Cruz, Florante N; Pesavento, Patricia A; Woolard, Kevin D

2016-11-01

Polyomavirus infection often results in persistence of the viral genome with little or no virion production. However, infection of certain cell types can result in high viral gene transcription and either cytolysis or neoplastic transformation. While infection by polyomavirus is common in humans and many animals, major questions regarding viral persistence of most polyomaviruses remain unanswered. Specifically, identification of target cells for viral infection and the mechanisms polyomaviruses employ to maintain viral genomes within cells are important not only in ascribing causality to polyomaviruses in disease, but in understanding specific mechanisms by which they cause disease. Here, we characterize the cell of origin in raccoon polyomavirus (RacPyV)-associated neuroglial brain tumours as a neural stem cell. Moreover, we identify an association between the viral genome and the host cell bromodomain protein, BRD4, which is involved in numerous cellular functions, including cell cycle progression, differentiation of stem cells, tethering of persistent DNA viruses, and regulation of viral and host-cell gene transcription. We demonstrate that inhibition of BRD4 by the small molecule inhibitors (+)-JQ1 and IBET-151 (GSK1210151A) results in reduced RacPyV genome within cells in vitro, as well as significant reduction of viral gene transcripts LT and VP1, highlighting its importance in both maintenance of the viral genome and in driving oncogenic transformation by RacPyV. This work implicates BRD4 as a central protein involved in RacPyV neuroglial tumour cell proliferation and in the maintenance of a stem cell state.

Konjungtivitis Viral: Diagnosis dan Terapi di Pelayanan Kesehatan Primer

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Ratna Sitompul

2017-04-01

, herpes zoster virus, poxvirus, myxovirus, paramyxovirus and arbovirus. It mostly occurs along or after respiratory tract infection as well as after contact with patients suffering from viral conjunctivitis. Clinical manifestations include redness, watery discharge, and pre auricular lymph enlargement. The manifestations are usually mild, self-limiting, and do not impair visual acuity thus viral conjunctivitis can be managed in primary health centers. However, there are cases which threaten visual acuity thus require referral to ophthalmologists or higher eye care services. Due to its high infectivity, patients should be educated to avoid of direct and indirect contact thus they would not spread the infection to environment. Although it is self-limiting, administration of artificial tears, topical antihistamine or cold compress, could reduce the manifestation. Antiviral agents are not required for conjunctivitis viral, unless for herpetic conjunctivitis. Kata kunci: epidemy, conjunctivitis, virus. Normal 0 false false false IN X-NONE X-NONE

Final Technical Report: Viral Infection of Subsurface Microorganisms and Metal/Radionuclide Transport

Energy Technology Data Exchange (ETDEWEB)

Weber, Karrie A.; Bender, Kelly S.; Li, Yusong

2013-09-28

Microbially mediated metabolisms have been identified as a significant factor either directly or indirectly impacting the fate and transport of heavy metal/radionuclide contaminants. To date microorganisms have been isolated from contaminated environments. Examination of annotated finished genome sequences of many of these subsurface isolates from DOE sites, revealed evidence of prior viral infection. To date the role that viruses play influencing microbial mortality and the resulting community structure which directly influences biogeochemical cycling in soils and sedimentary environments remains poorly understood. The objective of this exploratory study was to investigate the role of viral infection of subsurface bacteria and the formation of contaminant-bearing viral particles. This objective was approached by examining the following working hypotheses: (i) subsurface microorganisms are susceptible to viral infections by the indigenous subsurface viral community, and (ii) viral surfaces will adsorb heavy metals and radionuclides. Our results have addressed basic research needed to accomplish the BER Long Term Measure to provide sufficient scientific understanding such that DOE sites would be able to incorporate coupled physical, chemical and biological processes into decision making for environmental remediation or natural attenuation and long-term stewardship by establishing viral-microbial relationships on the subsequent fate and transport of heavy metals and radionuclides. Here we demonstrated that viruses play a significant role in microbial mortality and community structure in terrestrial subsurface sedimentary systems. The production of viral-like particles within subsurface sediments in response to biostimulation with dissolved organic carbon and a terminal electron acceptor resulted in the production of viral-like particles. Organic carbon alone did not result in significant viral production and required the addition of a terminal electron acceptor

Viral O-GalNAc peptide epitopes

DEFF Research Database (Denmark)

Olofsson, Sigvard; Blixt, Klas Ola; Bergström, Tomas

2016-01-01

Viral envelope glycoproteins are major targets for antibodies that bind to and inactivate viral particles. The capacity of a viral vaccine to induce virus-neutralizing antibodies is often used as a marker for vaccine efficacy. Yet the number of known neutralization target epitopes is restricted o...

Sub-optimal CD4 reconstitution despite viral suppression in an urban cohort on antiretroviral therapy (ART) in sub-Saharan Africa: frequency and clinical significance.

Science.gov (United States)

Nakanjako, Damalie; Kiragga, Agnes; Ibrahim, Fowzia; Castelnuovo, Barbara; Kamya, Moses R; Easterbrook, Philippa J

2008-10-28

A proportion of individuals who start antiretroviral therapy (ART) fail to achieve adequate CD4 cell reconstitution despite sustained viral suppression. We determined the frequency and clinical significance of suboptimal CD4 reconstitution despite viral suppression (SO-CD4) in an urban HIV research cohort in Kampala, Uganda. We analyzed data from a prospective research cohort of 559 patients initiating ART between 04/04-04/05. We described the patterns of SO-CD4 both in terms of:- I) magnitude of CD4 cell increase (a CD4 count increase ART) and II) failure to achieve a CD4 cell count above 200 cells/microl at 6,12 and 24 months of ART. Using criteria I) we used logistic regression to determine the predictors of SO-CD4. We compared the cumulative risk of clinical events (death and/or recurrent or new AIDS-defining illnesses) among patients with and without SO-CD4. Of 559 patients initiating ART, 386 (69%) were female. Median (IQR) age and baseline CD4 counts were 38 yrs (33-44) and 98 cells/microl (21-163) respectively; 414 (74%) started a d4T-based regimen (D4T+3TC+NVP) and 145 (26%) a ZDV-based regimen (ZDV+3TC+EFV). After 6, 12 and 24 months of ART, 380 (68%), 339 (61%) and 309 (55%) had attained and sustained HIV-RNA viral suppression. Of these, 78 (21%), 151 (45%) and 166 (54%) respectively had SO-CD4 based on criteria I), and 165(43%), 143(42%) and 58(19%) respectively based on criteria II). With both criteria combined, 56 (15%) and 129 (38%) had SO-CD4 at 6 and 12 months respectively. A high proportion (82% and 58%) of those that had SO-CD4 at 6 months (using criteria I) maintained SO-CD4 at 12 and 24 months respectively. There were no statistically significant differences in the incidence of clinical events among patients with [19/100PYO (12-29)] and without SO-CD4 [23/100PYO (19-28)]. Using criteria I), the frequency of SO-CD4 was 21% at 6 months. Majority of patients with SO-CD4 at 6 months maintained SO-CD4 up to 2 years. We recommend studies of CD4 T

The significance of reduced respiratory chain enzyme activities: clinical, biochemical and radiological associations.

Science.gov (United States)

Mordekar, S R; Guthrie, P; Bonham, J R; Olpin, S E; Hargreaves, I; Baxter, P S

2006-03-01

Mitochondrial diseases are an important group of neurometabolic disorders in children with varied clinical presentations and diagnosis that can be difficult to confirm. To report the significance of reduced respiratory chain enzyme (RCE) activity in muscle biopsy samples from children. Retrospective odds ratio was used to compare clinical and biochemical features, DNA studies, neuroimaging, and muscle biopsies in 18 children with and 48 without reduced RCE activity. Children with reduced RCE activity were significantly more likely to have consanguineous parents, to present with acute encephalopathy and lactic acidaemia and/or within the first year of life; to have an axonal neuropathy, CSF lactate >4 mmol/l; and/or to have signal change in the basal ganglia. There were positive associations with a maternal family history of possible mitochondrial cytopathy; a presentation with failure to thrive and lactic acidaemia, ragged red fibres, reduced fibroblast fatty acid oxidation and with an abnormal allopurinol loading test. There was no association with ophthalmic abnormalities, deafness, epilepsy or myopathy. The association of these clinical, biochemical and radiological features with reduced RCE activity suggests a possible causative link.

KSHV Rta promoter specification and viral reactivation

Directory of Open Access Journals (Sweden)

Jonathan eGuito

2012-02-01

Full Text Available Viruses are obligate intracellular pathogens whose biological success depends upon replication and packaging of viral genomes, and transmission of progeny viruses to new hosts. The biological success of herpesviruses is enhanced by their ability to reproduce their genomes without producing progeny viruses or killing the host cells, a process called latency. Latency permits a herpesvirus to remain undetected in its animal host for decades while maintaining the potential to reactivate, or switch, to a productive life cycle when host conditions are conducive to generating viral progeny. Direct interactions between many host and viral molecules are implicated in controlling herpesviral reactivation, suggesting complex biological networks that control the decision. One viral protein that is necessary and sufficient to switch latent KSHV into the lytic infection cycle is called K-Rta. Rta is a transcriptional activator that specifies promoters by binding direct DNA directly and interacting with cellular proteins. Among these cellular proteins, binding of K-Rta to RBP-Jk is essential for viral reactivation.. In contrast to the canonical model for Notch signaling, RBP-Jk is not uniformly and constitutively bound to the latent KSHV genome, but rather is recruited to DNA by interactions with K-Rta. Stimulation of RBP-Jk DNA binding requires high affinity binding of Rta to repetitive and palindromic CANT DNA repeats in promoters, and formation of ternary complexes with RBP-Jk. However, while K-Rta expression is necessary for initiating KSHV reactivation, K-Rta’s role as the switch is inefficient. Many factors modulate K-Rta’s function, suggesting that KSHV reactivation can be significantly regulated post-Rta expression and challenging the notion that herpesviral reactivation is bistable. This review analyzes rapidly evolving research on KSHV K-Rta to consider the role of K-Rta promoter specification in regulating the progression of KSHV reactivation.

Viral-bacterial associations in acute apical abscesses.

Science.gov (United States)

Ferreira, Dennis C; Rôças, Isabela N; Paiva, Simone S M; Carmo, Flávia L; Cavalcante, Fernanda S; Rosado, Alexandre S; Santos, Kátia R N; Siqueira, José F

2011-08-01

Viral-bacterial and bacterial synergism have been suggested to contribute to the pathogenesis of several human diseases. This study sought to investigate the possible associations between 9 candidate endodontic bacterial pathogens and 9 human viruses in samples from acute apical abscesses. DNA extracts from purulent exudate aspirates of 33 cases of acute apical abscess were surveyed for the presence of 9 selected bacterial species using a 16S ribosomal RNA gene-based nested polymerase chain reaction (PCR) approach. Single or nested PCR assays were used for detection of the human papillomavirus (HPV) and herpesviruses types 1 to 8. Two-thirds of the abscess samples were positive for at least one of the target viruses. Specifically, the most frequently detected viruses were HHV-8 (54.5%); HPV (9%); and varicella zoster virus (VZV), Epstein-Barr virus (EBV), and HHV-6 (6%). Bacterial DNA was present in all cases and the most prevalent bacterial species were Treponema denticola (70%), Tannerella forsythia (67%), Porphyromonas endodontalis (67%), Dialister invisus (61%), and Dialister pneumosintes (57.5%). HHV-8 was positively associated with 7 of the target bacterial species and HPV with 4, but all these associations were weak. Several bacterial pairs showed a moderate positive association. Viral coinfection was found in 6 abscess cases, but no significant viral association could be determined. Findings demonstrated that bacterial and viral DNA occurred concomitantly in two-thirds of the samples from endodontic abscesses. Although this may suggest a role for viruses in the etiology of apical abscesses, the possibility also exists that the presence of viruses in abscess samples is merely a consequence of the bacterially induced disease process. Further studies are necessary to clarify the role of these viral-bacterial interactions, if any, in the pathogenesis of acute apical abscesses. Copyright © 2011 Mosby, Inc. All rights reserved.

Latent viral reactivation is associated with changes in plasma antimicrobial protein concentrations during long-duration spaceflight

Science.gov (United States)

Spielmann, G.; Laughlin, M. S.; Kunz, H.; Crucian, B. E.; Quiriarte, H. D.; Mehta, S. K.; Pierson, D. L.; Simpson, R. J.

2018-05-01

Long duration spaceflights are associated with profound dysregulation of the immune system and latent viral reactivations. However, little is known on the impact of long duration spaceflight on innate immunity which raises concerns on crewmembers' ability to fight infections during a mission. The aim of this study was to determine the effects of spaceflight on plasma antimicrobial proteins (AMPs) and how these changes impact latent herpesvirus reactivations. Plasma, saliva and urine samples were obtained from 23 crewmembers before, during and after a 6-month mission on the International Space Station (ISS). Plasma AMP concentrations were determined by ELISA, and saliva Epstein-Barr virus (EBV) and varicella zoster virus (VZV) and urine cytomegalovirus (CMV) DNA levels were quantified by Real-Time PCR. There was a non-significant increase in plasma HNP1-3 and LL-37 during the early and middle stages of the missions, which was significantly associated with changes in viral DNA during and after spaceflight. Plasma HNP1-3 and Lysozyme increased at the late mission stages in astronauts who had exhibited EBV and VZV reactivations during the early flight stages. Following return to Earth and during recovery, HNP1-3 and lysozyme concentrations were associated with EBV and VZV viral DNA levels, reducing the magnitude of viral reactivation. Reductions in plasma LL-37 upon return were associated with greater CMV reactivation. This study shows that biomarkers of innate immunity appeared to be partially restored after 6-months in space and suggests that following adaptation to the space environment, plasma HNP1-3 and lysozyme facilitate the control of EBV and VZV reactivation rate and magnitude in space and upon return on earth. However, the landing-associated decline in plasma LL-37 may enhance the rate of CMV reactivation in astronauts following spaceflight, potentially compromising crewmember health after landing.

Viral infections in transplant recipients.

Science.gov (United States)

Razonable, R R; Eid, A J

2009-12-01

Solid organ and hematopoietic stem cell transplant recipients are uniquely predisposed to develop clinical illness, often with increased severity, due to a variety of common and opportunistic viruses. Patients may acquire viral infections from the donor (donor-derived infections), from reactivation of endogenous latent virus, or from the community. Herpes viruses, most notably cytomegalovirus and Epstein Barr virus, are the most common among opportunistic viral pathogens that cause infection after solid organ and hematopoietic stem cell transplantation. The polyoma BK virus causes opportunistic clinical syndromes predominantly in kidney and allogeneic hematopoietic stem cell transplant recipients. The agents of viral hepatitis B and C present unique challenges particularly among liver transplant recipients. Respiratory viral illnesses due to influenza, respiratory syncytial virus, and parainfluenza virus may affect all types of transplant recipients, although severe clinical disease is observed more commonly among lung and allogeneic hematopoietic stem cell transplant recipients. Less common viral infections affecting transplant recipients include those caused by adenoviruses, parvovirus B19, and West Nile virus. Treatment for viruses with proven effective antiviral drug therapies should be complemented by reduction in the degree of immunosuppression. For others with no proven antiviral drugs for therapy, reduction in the degree of immunosuppression remains as the sole effective strategy for management. Prevention of viral infections is therefore of utmost importance, and this may be accomplished through vaccination, antiviral strategies, and aggressive infection control measures.

L Particles Transmit Viral Proteins from Herpes Simplex Virus 1-Infected Mature Dendritic Cells to Uninfected Bystander Cells, Inducing CD83 Downmodulation.

Science.gov (United States)

Heilingloh, Christiane S; Kummer, Mirko; Mühl-Zürbes, Petra; Drassner, Christina; Daniel, Christoph; Klewer, Monika; Steinkasserer, Alexander

2015-11-01

Mature dendritic cells (mDCs) are known as the most potent antigen-presenting cells (APCs) since they are also able to prime/induce naive T cells. Thus, mDCs play a pivotal role during the induction of antiviral immune responses. Remarkably, the cell surface molecule CD83, which was shown to have costimulatory properties, is targeted by herpes simplex virus 1 (HSV-1) for viral immune escape. Infection of mDCs with HSV-1 results in downmodulation of CD83, resulting in reduced T cell stimulation. In this study, we report that not only infected mDCs but also uninfected bystander cells in an infected culture show a significant CD83 reduction. We demonstrate that this effect is independent of phagocytosis and transmissible from infected to uninfected mDCs. The presence of specific viral proteins found in these uninfected bystander cells led to the hypothesis that viral proteins are transferred from infected to uninfected cells via L particles. These L particles are generated during lytic replication in parallel with full virions, called H particles. L particles contain viral proteins but lack the viral capsid and DNA. Therefore, these particles are not infectious but are able to transfer several viral proteins. Incubation of mDCs with L particles indeed reduced CD83 expression on uninfected bystander DCs, providing for the first time evidence that functional viral proteins are transmitted via L particles from infected mDCs to uninfected bystander cells, thereby inducing CD83 downmodulation. HSV-1 has evolved a number of strategies to evade the host's immune system. Among others, HSV-1 infection of mDCs results in an inhibited T cell activation caused by degradation of CD83. Interestingly, CD83 is lost not only from HSV-1-infected mDCs but also from uninfected bystander cells. The release of so-called L particles, which contain several viral proteins but lack capsid and DNA, during infection is a common phenomenon observed among several viruses, such as human

Detection of serum leptin levels in patients with viral hepatitis and fatty liver

International Nuclear Information System (INIS)

Sun Shuhong; Sun Bingmei; Niu Airong; Lan Cuixia

2007-01-01

In order to find out the correlations between serum leptin levels and viral hepatitis, the serum leptin levels in 167 patients with viral chronic hepatitis, 87 patients with fatty liver, and 80 control subjects were determined by radioimmunoassay. The liver function (ALT, AST), glucose(Glu) and total cholesterol(TC) in these patients were also measured. Compared with controls and patients with fatty liver, the levels of serum leptin in patients with viral hepatitis were significantly increased (P 0.05). The increase of serum leptin levels in the patients with viral hepatitis was correlated positively with the severity of liver inflammation. Therefore, the leptin can be regarded as an indicator to reflect the severity of liver inflammation. (authors)

Assembly of viral genomes from metagenomes

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Saskia L Smits

2014-12-01

Full Text Available Viral infections remain a serious global health issue. Metagenomic approaches are increasingly used in the detection of novel viral pathogens but also to generate complete genomes of uncultivated viruses. In silico identification of complete viral genomes from sequence data would allow rapid phylogenetic characterization of these new viruses. Often, however, complete viral genomes are not recovered, but rather several distinct contigs derived from a single entity, some of which have no sequence homology to any known proteins. De novo assembly of single viruses from a metagenome is challenging, not only because of the lack of a reference genome, but also because of intrapopulation variation and uneven or insufficient coverage. Here we explored different assembly algorithms, remote homology searches, genome-specific sequence motifs, k-mer frequency ranking, and coverage profile binning to detect and obtain viral target genomes from metagenomes. All methods were tested on 454-generated sequencing datasets containing three recently described RNA viruses with a relatively large genome which were divergent to previously known viruses from the viral families Rhabdoviridae and Coronaviridae. Depending on specific characteristics of the target virus and the metagenomic community, different assembly and in silico gap closure strategies were successful in obtaining near complete viral genomes.

Viral marketing as epidemiological model

OpenAIRE

Rodrigues, Helena Sofia; Fonseca, Manuel

2015-01-01

In epidemiology, an epidemic is defined as the spread of an infectious disease to a large number of people in a given population within a short period of time. In the marketing context, a message is viral when it is broadly sent and received by the target market through person-to-person transmission. This specific marketing communication strategy is commonly referred as viral marketing. Due to this similarity between an epidemic and the viral marketing process and because the understanding of...

Ethical Considerations in Research Participation Virality.

Science.gov (United States)

Ellis-Barton, Carol

2016-07-01

This article seeks to commence and encourage discussion around the upcoming ethical challenges of virality in network structures. When the call for participation in a research project on lupus in Ireland went from an advertisement in a newsletter to a meme (unit of transmissible information) on a closed Facebook page, the ethical considerations of virality were raised. The article analyzes the Association of Internet Researchers guidelines, Facebook policies, and the context of privacy in relation to virality. Virality creates the leverage for methodological pluralism. The nature of the inquiry can determine the method rather than the other way around. Viral ethical considerations are evolving due to the cyber world becoming the primary meme of communication, with flexibility in the researcher's protocol providing opportunities for efficient, cost-effective, and diverse recruitment. © The Author(s) 2016.

The N-Terminal of Aquareovirus NS80 Is Required for Interacting with Viral Proteins and Viral Replication.

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Jie Zhang

Full Text Available Reovirus replication and assembly occurs within viral inclusion bodies that formed in specific intracellular compartments of cytoplasm in infected cells. Previous study indicated that aquareovirus NS80 is able to form inclusion bodies, and also can retain viral proteins within its inclusions. To better understand how NS80 performed in viral replication and assembly, the functional regions of NS80 associated with other viral proteins in aquareovirus replication were investigated in this study. Deletion mutational analysis and rotavirus NSP5-based protein association platform were used to detect association regions. Immunofluorescence images indicated that different N-terminal regions of NS80 could associate with viral proteins VP1, VP4, VP6 and NS38. Further co-immunoprecipitation analysis confirmed the interaction between VP1, VP4, VP6 or NS38 with different regions covering the N-terminal amino acid (aa, 1-471 of NS80, respectively. Moreover, removal of NS80 N-terminal sequences required for interaction with proteins VP1, VP4, VP6 or NS38 not only prevented the capacity of NS80 to support viral replication in NS80 shRNA-based replication complementation assays, but also inhibited the expression of aquareovirus proteins, suggesting that N-terminal regions of NS80 are necessary for viral replication. These results provided a foundational basis for further understanding the role of NS80 in viral replication and assembly during aquareovirus infection.

How Can Viral Dynamics Models Inform Endpoint Measures in Clinical Trials of Therapies for Acute Viral Infections?

Directory of Open Access Journals (Sweden)

Carolin Vegvari

Full Text Available Acute viral infections pose many practical challenges for the accurate assessment of the impact of novel therapies on viral growth and decay. Using the example of influenza A, we illustrate how the measurement of infection-related quantities that determine the dynamics of viral load within the human host, can inform investigators on the course and severity of infection and the efficacy of a novel treatment. We estimated the values of key infection-related quantities that determine the course of natural infection from viral load data, using Markov Chain Monte Carlo methods. The data were placebo group viral load measurements collected during volunteer challenge studies, conducted by Roche, as part of the oseltamivir trials. We calculated the values of the quantities for each patient and the correlations between the quantities, symptom severity and body temperature. The greatest variation among individuals occurred in the viral load peak and area under the viral load curve. Total symptom severity correlated positively with the basic reproductive number. The most sensitive endpoint for therapeutic trials with the goal to cure patients is the duration of infection. We suggest laboratory experiments to obtain more precise estimates of virological quantities that can supplement clinical endpoint measurements.

Four-phonon scattering significantly reduces intrinsic thermal conductivity of solids

Science.gov (United States)

Feng, Tianli; Lindsay, Lucas; Ruan, Xiulin

2017-10-01

For decades, the three-phonon scattering process has been considered to govern thermal transport in solids, while the role of higher-order four-phonon scattering has been persistently unclear and so ignored. However, recent quantitative calculations of three-phonon scattering have often shown a significant overestimation of thermal conductivity as compared to experimental values. In this Rapid Communication we show that four-phonon scattering is generally important in solids and can remedy such discrepancies. For silicon and diamond, the predicted thermal conductivity is reduced by 30% at 1000 K after including four-phonon scattering, bringing predictions in excellent agreement with measurements. For the projected ultrahigh-thermal conductivity material, zinc-blende BAs, a competitor of diamond as a heat sink material, four-phonon scattering is found to be strikingly strong as three-phonon processes have an extremely limited phase space for scattering. The four-phonon scattering reduces the predicted thermal conductivity from 2200 to 1400 W/m K at room temperature. The reduction at 1000 K is 60%. We also find that optical phonon scattering rates are largely affected, being important in applications such as phonon bottlenecks in equilibrating electronic excitations. Recognizing that four-phonon scattering is expensive to calculate, in the end we provide some guidelines on how to quickly assess the significance of four-phonon scattering, based on energy surface anharmonicity and the scattering phase space. Our work clears the decades-long fundamental question of the significance of higher-order scattering, and points out ways to improve thermoelectrics, thermal barrier coatings, nuclear materials, and radiative heat transfer.

Associations between national viral hepatitis policies/programmes and country-level socioeconomic factors: a sub-analysis of data from the 2013 WHO viral hepatitis policy report.

Science.gov (United States)

Lazarus, Jeffrey V; Sperle, Ida; Safreed-Harmon, Kelly; Gore, Charles; Cebolla, Beatriz; Spina, Alexander

2017-07-26

As more countries worldwide develop national viral hepatitis strategies, it is important to ask whether context-specific factors affect their decision-making. This study aimed to determine whether country-level socioeconomic factors are associated with viral hepatitis programmes and policy responses across WHO Member States (MS). WHO MS focal points completed a questionnaire on national viral hepatitis policies. This secondary analysis of data reported in the 2013 Global Policy Report on the Prevention and Control of Viral Hepatitis in WHO Member States used logistic regression to examine associations between four survey questions and four socioeconomic factors: country income level, Human Development Index (HDI), health expenditure and physician density. This analysis included 119 MS. MS were more likely to have routine viral hepatitis surveillance and to have a national strategy and/or policy/guidelines for preventing infection in healthcare settings if they were in the higher binary categories for income level, HDI, health expenditure and physician density. In multivariable analyses, the only significant finding was a positive association between having routine surveillance and being in the higher binary HDI category (adjusted odds ratio 26; 95% confidence interval 2.0-340). Countries with differing socioeconomic status indicators did not appear to differ greatly regarding the existence of key national policies and programmes. A more nuanced understanding of the multifaceted interactions of socioeconomic factors, health policy, service delivery and health outcomes is needed to support country-level efforts to eliminate viral hepatitis.

Staphylococcus aureus α-toxin modulates skin host response to viral infection.

Science.gov (United States)

Bin, Lianghua; Kim, Byung Eui; Brauweiler, Anne; Goleva, Elena; Streib, Joanne; Ji, Yinduo; Schlievert, Patrick M; Leung, Donald Y M

2012-09-01

Patients with atopic dermatitis (AD) with a history of eczema herpeticum have increased staphylococcal colonization and infections. However, whether Staphylococcus aureus alters the outcome of skin viral infection has not been determined. We investigated whether S aureus toxins modulated host response to herpes simplex virus (HSV) 1 and vaccinia virus (VV) infections in normal human keratinocytes (NHKs) and in murine infection models. NHKs were treated with S aureus toxins before incubation of viruses. BALB/c mice were inoculated with S aureus 2 days before VV scarification. Viral loads of HSV-1 and VV were evaluated by using real-time PCR, a viral plaque-forming assay, and immunofluorescence staining. Small interfering RNA duplexes were used to knockdown the gene expression of the cellular receptor of α-toxin, a disintegrin and metalloprotease 10 (ADAM10). ADAM10 protein and α-toxin heptamers were detected by using Western blot assays. We demonstrate that sublytic staphylococcal α-toxin increases viral loads of HSV-1 and VV in NHKs. Furthermore, we demonstrate in vivo that the VV load is significantly greater (P skin inoculated with an α-toxin-producing S aureus strain compared with murine skin inoculated with the isogenic α-toxin-deleted strain. The viral enhancing effect of α-toxin is mediated by ADAM10 and is associated with its pore-forming property. Moreover, we demonstrate that α-toxin promotes viral entry in NHKs. The current study introduces the novel concept that staphylococcal α-toxin promotes viral skin infection and provides a mechanism by which S aureus infection might predispose the host toward disseminated viral infections. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Evaluation of adults with acute viral hepatitis a and review of the literature.

Science.gov (United States)

Tekin, R; Yolbas, I; Dal, T; Demirpençe, Ö; Kaya, S; Bozkurt, F; Deveci, Ö; Çelen, M K; Tekin, A

2013-01-01

In developing countries HAV infection is very common in the first years of life and it is often asymptomatic. However especially in regions of intermediate endemicity, exposure to the virus may delay and outbreaks of hepatitis A may be encountered in adults. The aim of this study is to evaluate the clinical and laboratory findings and risk factors of adults with acute viral hepatitis A. In present study we evaluated 203 patient with acute viral hepatitis A, who were admitted to four different hospitals of three cities of Turkey between January 2000-December 2011, retrospectively. The diagnosis of acute viral hepatitis A was performed by laboratory findings and clinically. In a total of 203 patients, 120 (59.1%) patients were male and 83 (40.9%) were female. Mean age of cases with acute viral hepatitis A was 24.7 +11.8 years (ranged 15 to 82 years old). Acute viral hepatitis A were seen in patient who were 15-20 years and 21-30 years old, commonly. Jaundice (74%), fatigue (68%), nausea- vomiting (56%) and dark urine (48%) were the most common symptoms in cases. Prolonged cholestasis (6.8%) was the most common atypical manifestation. Prolonged jaundice was more frequent in the cases with positive HBsAg (P viral hepatitis A can cause atypical presentations such as prolonged cholestasis, acute kidney injury and fulminant hepatitis. Some precautions such as routine vaccination program, improvement of hygiene conditions and informing people about it, should be taken for reducing of acute viral hepatitis A infection incidence.

Constrained pattern of viral evolution in acute and early HCV infection limits viral plasticity.

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Katja Pfafferott

2011-02-01

Full Text Available Cellular immune responses during acute Hepatitis C virus (HCV and HIV infection are a known correlate of infection outcome. Viral adaptation to these responses via mutation(s within CD8+ T-cell epitopes allows these viruses to subvert host immune control. This study examined HCV evolution in 21 HCV genotype 1-infected subjects to characterise the level of viral adaptation during acute and early HCV infection. Of the total mutations observed 25% were within described CD8+ T-cell epitopes or at viral adaptation sites. Most mutations were maintained into the chronic phase of HCV infection (75%. The lack of reversion of adaptations and high proportion of silent substitutions suggests that HCV has structural and functional limitations that constrain evolution. These results were compared to the pattern of viral evolution observed in 98 subjects during a similar phase in HIV infection from a previous study. In contrast to HCV, evolution during acute HIV infection is marked by high levels of amino acid change relative to silent substitutions, including a higher proportion of adaptations, likely reflecting strong and continued CD8+ T-cell pressure combined with greater plasticity of the virus. Understanding viral escape dynamics for these two viruses is important for effective T cell vaccine design.

First insight into the viral community of the cnidarian model metaorganism Aiptasia using RNA-Seq data

KAUST Repository

Brüwer, Jan D.

2018-03-01

Current research posits that all multicellular organisms live in symbioses with associated microorganisms and form so-called metaorganisms or holobionts. Cnidarian metaorganisms are of specific interest given that stony corals provide the foundation of the globally threatened coral reef ecosystems. To gain first insight into viruses associated with the coral model system Aiptasia (sensu Exaiptasia pallida), we analyzed an existing RNA-Seq dataset of aposymbiotic, partially populated, and fully symbiotic Aiptasia CC7 anemones with Symbiodinium. Our approach included the selective removal of anemone host and algal endosymbiont sequences and subsequent microbial sequence annotation. Of a total of 297 million raw sequence reads, 8.6 million (∼3%) remained after host and endosymbiont sequence removal. Of these, 3,293 sequences could be assigned as of viral origin. Taxonomic annotation of these sequences suggests that Aiptasia is associated with a diverse viral community, comprising 116 viral taxa covering 40 families. The viral assemblage was dominated by viruses from the families Herpesviridae (12.00%), Partitiviridae (9.93%), and Picornaviridae (9.87%). Despite an overall stable viral assemblage, we found that some viral taxa exhibited significant changes in their relative abundance when Aiptasia engaged in a symbiotic relationship with Symbiodinium. Elucidation of viral taxa consistently present across all conditions revealed a core virome of 15 viral taxa from 11 viral families, encompassing many viruses previously reported as members of coral viromes. Despite the non-random selection of viral genetic material due to the nature of the sequencing data analyzed, our study provides a first insight into the viral community associated with Aiptasia. Similarities of the Aiptasia viral community with those of corals corroborate the application of Aiptasia as a model system to study coral holobionts. Further, the change in abundance of certain viral taxa across different

Translational Implication of Galectin-9 in the Pathogenesis and Treatment of Viral Infection

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Jenn-Haung Lai

2017-10-01

Full Text Available The interaction between galectin-9 and its receptor, Tim-3, triggers a series of signaling events that regulate immune responses. The expression of galectin-9 has been shown to be increased in a variety of target cells of many different viruses, such as hepatitis C virus (HCV, hepatitis B virus (HBV, herpes simplex virus (HSV, influenza virus, dengue virus (DENV, and human immunodeficiency virus (HIV. This enhanced expression of galectin-9 following viral infection promotes significant changes in the behaviors of the virus-infected cells, and the resulting events tightly correlate with the immunopathogenesis of the viral disease. Because the human immune response to different viral infections can vary, and the lack of appropriate treatment can have potentially fatal consequences, understanding the implications of galectin-9 is crucial for developing better methods for monitoring and treating viral infections. This review seeks to address how we can apply the current understanding of galectin-9 function to better understand the pathogenesis of viral infection and better treat viral diseases.

Bile acids for viral hepatitis

DEFF Research Database (Denmark)

Chen, Weikeng; Liu, J; Gluud, C

2007-01-01

Trials have assessed bile acids for patients with viral hepatitis, but no consensus has been reached regarding their usefulness.......Trials have assessed bile acids for patients with viral hepatitis, but no consensus has been reached regarding their usefulness....

Late presentation of chronic viral hepatitis for medical care

DEFF Research Database (Denmark)

Mauss, Stefan; Pol, Stanislas; Buti, Maria

2017-01-01

, and relevant stakeholders including patient advocacy groups, health policy-makers, international health organisations and surveillance experts, met in 2014 and 2015 to develop a draft consensus definition of late presentation with viral hepatitis for medical care. This was refined through subsequent...... consultations among the group. RESULTS: Two definitions were agreed upon. Presentation with advanced liver disease caused by chronic viral hepatitis for medical care is defined as a patient with chronic hepatitis B and C and significant fibrosis (≥ F3 assessed by either APRI score > 1.5, FIB-4 > 3.25, Fibrotest...

Viral Hepatitis: A through E and Beyond

Science.gov (United States)

... National Digestive Diseases Information Clearinghouse What is viral hepatitis? Viral hepatitis is inflammation of the liver caused by ... and serious. Drugs are available to treat chronic hepatitis. 4 Viral Hepatitis: A through E and Beyond What else ...

Alzheimer's associated β-amyloid protein inhibits influenza A virus and modulates viral interactions with phagocytes.

Directory of Open Access Journals (Sweden)

Mitchell R White

Full Text Available Accumulation of β-Amyloid (βA is a key pathogenetic factor in Alzheimer's disease; however, the normal function of βA is unknown. Recent studies have shown that βA can inhibit growth of bacteria and fungi. In this paper we show that βA also inhibits replication of seasonal and pandemic strains of H3N2 and H1N1 influenza A virus (IAV in vitro. The 42 amino acid fragment of βA (βA42 had greater activity than the 40 amino acid fragment. Direct incubation of the virus with βA42 was needed to achieve optimal inhibition. Using quantitative PCR assays βA42 was shown to reduce viral uptake by epithelial cells after 45 minutes and to reduce supernatant virus at 24 hours post infection. βA42 caused aggregation of IAV particles as detected by light transmission assays and electron and confocal microscopy. βA42 did not stimulate neutrophil H2O2 production or extracellular trap formation on its own, but it increased both responses stimulated by IAV. In addition, βA42 increased uptake of IAV by neutrophils. βA42 reduced viral protein synthesis in monocytes and reduced IAV-induced interleukin-6 production by these cells. Hence, we demonstrate for the first time that βA has antiviral activity and modulates viral interactions with phagocytes.

Role of RNase MRP in viral RNA degradation and RNA recombination.

Science.gov (United States)

Jaag, Hannah M; Lu, Qiasheng; Schmitt, Mark E; Nagy, Peter D

2011-01-01

RNA degradation, together with RNA synthesis, controls the steady-state level of viral RNAs in infected cells. The endoribonucleolytic cleavage of viral RNA is important not only for viral RNA degradation but for RNA recombination as well, due to the participation of some RNA degradation products in the RNA recombination process. To identify host endoribonucleases involved in degradation of Tomato bushy stunt virus (TBSV) in a Saccharomyces cerevisiae model host, we tested eight known endoribonucleases. Here we report that downregulation of SNM1, encoding a component of the RNase MRP, and a temperature-sensitive mutation in the NME1 gene, coding for the RNA component of RNase MRP, lead to reduced production of the endoribonucleolytically cleaved TBSV RNA in yeast. We also show that the highly purified yeast RNase MRP cleaves the TBSV RNA in vitro, resulting in TBSV RNA degradation products similar in size to those observed in yeast cells. Knocking down the NME1 homolog in Nicotiana benthamiana also led to decreased production of the cleaved TBSV RNA, suggesting that in plants, RNase MRP is involved in TBSV RNA degradation. Altogether, this work suggests a role for the host endoribonuclease RNase MRP in viral RNA degradation and recombination.

Viral Hepatitis: Information for Gay and Bisexual Men

Science.gov (United States)

VIRAL HEPATITIS Information for Gay and Bisexual Men What is viral hepatitis? Viral hepatitis is an infection of the liver caused by one of several ... each virus is spread in different ways. Are gay and bisexual men at risk for viral hepatitis? ...

Oxygen minimum zones harbour novel viral communities with low diversity.

Science.gov (United States)

Cassman, Noriko; Prieto-Davó, Alejandra; Walsh, Kevin; Silva, Genivaldo G Z; Angly, Florent; Akhter, Sajia; Barott, Katie; Busch, Julia; McDole, Tracey; Haggerty, J Matthew; Willner, Dana; Alarcón, Gadiel; Ulloa, Osvaldo; DeLong, Edward F; Dutilh, Bas E; Rohwer, Forest; Dinsdale, Elizabeth A

2012-11-01

Oxygen minimum zones (OMZs) are oceanographic features that affect ocean productivity and biodiversity, and contribute to ocean nitrogen loss and greenhouse gas emissions. Here we describe the viral communities associated with the Eastern Tropical South Pacific (ETSP) OMZ off Iquique, Chile for the first time through abundance estimates and viral metagenomic analysis. The viral-to-microbial ratio (VMR) in the ETSP OMZ fluctuated in the oxycline and declined in the anoxic core to below one on several occasions. The number of viral genotypes (unique genomes as defined by sequence assembly) ranged from 2040 at the surface to 98 in the oxycline, which is the lowest viral diversity recorded to date in the ocean. Within the ETSP OMZ viromes, only 4.95% of genotypes were shared between surface and anoxic core viromes using reciprocal BLASTn sequence comparison. ETSP virome comparison with surface marine viromes (Sargasso Sea, Gulf of Mexico, Kingman Reef, Chesapeake Bay) revealed a dissimilarity of ETSP OMZ viruses to those from other oceanic regions. From the 1.4 million non-redundant DNA sequences sampled within the altered oxygen conditions of the ETSP OMZ, more than 97.8% were novel. Of the average 3.2% of sequences that showed similarity to the SEED non-redundant database, phage sequences dominated the surface viromes, eukaryotic virus sequences dominated the oxycline viromes, and phage sequences dominated the anoxic core viromes. The viral community of the ETSP OMZ was characterized by fluctuations in abundance, taxa and diversity across the oxygen gradient. The ecological significance of these changes was difficult to predict; however, it appears that the reduction in oxygen coincides with an increased shedding of eukaryotic viruses in the oxycline, and a shift to unique viral genotypes in the anoxic core. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

Genetic associations with viral respiratory illnesses and asthma control in children

DEFF Research Database (Denmark)

Loisel, D A; Du, G; Ahluwalia, T S

2016-01-01

of asthma control phenotypes was performed in 2128 children in the Copenhagen Prospective Study on Asthma in Childhood (COPSAC). Significant associations in RhinoGen were further validated using virus-induced wheezing illness and asthma phenotypes in an independent sample of 122 children enrolled...... in the Childhood Origins of Asthma (COAST) birth cohort study. RESULTS: A significant excess of P values smaller than 0.05 was observed in the analysis of the 10 RhinoGen phenotypes. Polymorphisms in 12 genes were significantly associated with variation in the four phenotypes showing a significant enrichment...... differences in childhood viral respiratory illnesses and virus-induced exacerbations of asthma. Defining mechanisms of these associations may provide insight into the pathogenesis of viral respiratory infections and virus-induced exacerbations of asthma....

Acute mucosal pathogenesis of feline immunodeficiency virus is independent of viral dose in vaginally infected cats

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Egan Erin A

2010-01-01

Full Text Available Abstract Background The mucosal pathogenesis of HIV has been shown to be an important feature of infection and disease progression. HIV-1 infection causes depletion of intestinal lamina propria CD4+ T cells (LPL, therefore, intestinal CD4+ T cell preservation may be a useful correlate of protection in evaluating vaccine candidates. Vaccine studies employing the cat/FIV and macaque/SIV models frequently use high doses of parenterally administered challenge virus to ensure high plasma viremia in control animals. However, it is unclear if loss of mucosal T cells would occur regardless of initial viral inoculum dose. The objective of this study was to determine the acute effect of viral dose on mucosal leukocytes and associated innate and adaptive immune responses. Results Cats were vaginally inoculated with a high, middle or low dose of cell-associated and cell-free FIV. PBMC, serum and plasma were assessed every two weeks with tissues assessed eight weeks following infection. We found that irrespective of mucosally administered viral dose, FIV infection was induced in all cats. However, viremia was present in only half of the cats, and viral dose was unrelated to the development of viremia. Importantly, regardless of viral dose, all cats experienced significant losses of intestinal CD4+ LPL and CD8+ intraepithelial lymphocytes (IEL. Innate immune responses by CD56+CD3- NK cells correlated with aviremia and apparent occult infection but did not protect mucosal T cells. CD4+ and CD8+ T cells in viremic cats were more likely to produce cytokines in response to Gag stimulation, whereas aviremic cats T cells tended to produce cytokines in response to Env stimulation. However, while cell-mediated immune responses in aviremic cats may have helped reduce viral replication, they could not be correlated to the levels of viremia. Robust production of anti-FIV antibodies was positively correlated with the magnitude of viremia. Conclusions Our results indicate

Visual pathways involvement in children with acute viral encephalitis

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Voitenkov Vladislav Borisovich

2013-10-01

Full Text Available AIM: To investigate extent and nature of visual pathways involvement in children with acute viral encephalitis. METHODS: Thirty patients(age 5-12 yearswith acute viral encephalitis underwent visual evoked potentials(VEPinvestigation within 12 days from the appearance of the first signs of disease. Latency and amplitude of P100 peak were compared with normative data and between patients with varicella and tick-borne encephalitis. RESULTS: There were no significant differences between children with these two forms of encephalitis. In the whole group in 40% of the cases signs of the visual cortex dysfunction(P100 amplitude loweringand mild slowing of the conductivity along the visual pathways(P100 latency lengtheningwere seen. In 3% of the cases retrobulbar optic neuritis was diagnosed. CONCLUSION:The results indicate that visual pathway have good endurance to the viral encephalitis anatomically, but functionally visual cortex is quite vulnerable towards general disturbances caused by this kind of illness.

Clinical definition of respiratory viral infections in young children and potential bronchiolitis misclassification.

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Megalaa, Rosemary; Perez, Geovanny F; Kilaikode-Cheruveettara, Sasikumar; Kotwal, Nidhi; Rodriguez-Martinez, Carlos E; Nino, Gustavo

2018-01-01

Viral respiratory infections are often grouped as a single respiratory syndrome named 'viral bronchiolitis', independently of the viral etiology or individual risk factors. Clinical trials and guidelines have used a more stringent definition of viral bronchiolitis, including only the first episode of wheezing in children less than 12 months of age without concomitant respiratory comorbidities. There is increasing evidence suggesting that this definition is not being followed by pediatric care providers, but it is unclear to what extent viral respiratory infections are currently misclassified as viral bronchiolitis using standard definitions. We conducted a retrospective analysis of hospitalized young children (≤3 years) due to viral respiratory infections. Bronchiolitis was defined as the first wheezing episode less than 12 months of age. Demographic variables and comorbidities were obtained by electronic medical record review. The study comprised a total of 513 hospitalizations (n=453). Viral bronchiolitis was diagnosed in 144 admissions (28.1%). Notably, we identified that the majority of children diagnosed with bronchiolitis (63%) were misclassified as they had prior episodes of wheezing. Many children with bronchiolitis misclassification had significant comorbidities, including prematurity (51%), neuromuscular conditions (9.8%), and congenital heart disease (9.8%). Misclassification of bronchiolitis is a common problem that may lead to inappropriate management of viral respiratory infections in young children. A comprehensive approach that takes into consideration viral etiology and individual risk factors may lead to a more accurate clinical assessment of this condition and would potentially prevent bronchiolitis misclassification. © American Federation for Medical Research (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

HBsAg level and hepatitis B viral load correlation with focus on pregnancy

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Belopolskaya, Maria; Avrutin, Viktor; Firsov, Sergey; Yakovlev, Alexey

2015-01-01

Background Viral load measurement is necessary to estimate mother-to-child transmission risk for women with chronic hepatitis B (CHB), however, it is expensive. The present study aimed to investigate the relationship between HBsAg and hepatitis B virus (HBV) DNA levels, and to determine potential applications of HBsAg level monitoring for estimating viral load. Methods 85 patients with CHB (31 pregnant women, 26 non-pregnant women, 28 men) were included in the study. HBV DNA level was measured by real-time PCR, and HBsAg level by chemiluminescent immunoassay method. Dependency between viral load and HBsAg level was determined by Spearman correlation coefficient ρ. Results The correlation between HBsAg and HBV DNA levels was significant for all patients [ρ=0.3762 (P<0.0005; n=85)]. In the group of pregnant women, a low (unmeasurable) HBV DNA level led to a decrease in the Spearman coefficient ρ. In almost all cases a low level of the HBsAg corresponded to a low HBV DNA level. Only 2 patients had a low level of HBsAg and a relatively high viral load. By contrast, a high HBsAg level was observed in patients both with high and low viral load. Conclusions Correlation between HBsAg and HBV DNA levels is significant. In most cases, a low level of HBsAg indicates a low HBV DNA level, whereas a high HBsAg level does not always correspond to a high viral load. The measurement of HBV DNA level is necessary for pregnant women with a high HBsAg level. PMID:26127004

Associations between national viral hepatitis policies/programmes and country-level socioeconomic factors: a sub-analysis of data from the 2013 WHO viral hepatitis policy report

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Jeffrey V Lazarus

2017-07-01

Full Text Available Abstract Background As more countries worldwide develop national viral hepatitis strategies, it is important to ask whether context-specific factors affect their decision-making. This study aimed to determine whether country-level socioeconomic factors are associated with viral hepatitis programmes and policy responses across WHO Member States (MS. Methods WHO MS focal points completed a questionnaire on national viral hepatitis policies. This secondary analysis of data reported in the 2013 Global Policy Report on the Prevention and Control of Viral Hepatitis in WHO Member States used logistic regression to examine associations between four survey questions and four socioeconomic factors: country income level, Human Development Index (HDI, health expenditure and physician density. Results This analysis included 119 MS. MS were more likely to have routine viral hepatitis surveillance and to have a national strategy and/or policy/guidelines for preventing infection in healthcare settings if they were in the higher binary categories for income level, HDI, health expenditure and physician density. In multivariable analyses, the only significant finding was a positive association between having routine surveillance and being in the higher binary HDI category (adjusted odds ratio 26; 95% confidence interval 2.0–340. Conclusion Countries with differing socioeconomic status indicators did not appear to differ greatly regarding the existence of key national policies and programmes. A more nuanced understanding of the multifaceted interactions of socioeconomic factors, health policy, service delivery and health outcomes is needed to support country-level efforts to eliminate viral hepatitis.

Studies on some biochemical parameters in viral hepatitis patients

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El-Sherbiny, E.M.

2002-01-01

The present investigation deals with studying liver amino transferases (ALT. AST). Cholesterol and triglycerides. As well as testosterone and protection hormones in blood of Egyptian men infected with hepatitis C virus.hepatitis B virus and mixed B and C viruses. These biochemical parameters were evaluated to be used in diagnosis and prognosis of viral hepatitis. Which considered the most important health problem in Egypt and developing countries. Biochemical analysis were performed using spectrophotometric and radioimmunoassay techniques. All data will be subjected to statistical analysis in order to detect the most suitable biochemical analysis that can be used as specific tests for early diagnosis of viral hepatitis and to detect the parameters that show abnormalities among the different groups of infected patients. The data revealed that AST and ALT levels were increased in all patient groups. Concerning the level of triglycerides, it was increased only in the group of mixed viral hepatitis B and C, while cholesterol showed non-significant changes in all viral hepatitis groups. The sex hormone testosterone was decreased in all infected patients while the prolactin level was increased only in case of patients infected with mixed B and C viruses. However, these abnormal values in such sex hormones play a serious role in male sterility

Prevalence and evaluation strategies for viral contamination in food products: Risk to human health-a review.

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Shukla, Shruti; Cho, Hyunjeong; Kwon, O Jun; Chung, Soo Hyun; Kim, Myunghee

2018-02-11

Nowadays, viruses of foodborne origin such as norovirus and hepatitis A are considered major causes of foodborne gastrointestinal illness with widespread distribution worldwide. A number of foodborne outbreaks associated with food products of animal and non-animal origins, which often involve multiple cases of variety of food streams, have been reported. Although several viruses, including rotavirus, adenovirus, astrovirus, parvovirus, and other enteroviruses, significantly contribute to incidence of gastrointestinal diseases, systematic information on the role of food in transmitting such viruses is limited. Most of the outbreak cases caused by infected food handlers were the source of 53% of total outbreaks. Therefore, prevention and hygiene measures to reduce the frequency of foodborne virus outbreaks should focus on food workers and production site of food products. Pivotal strategies, such as proper investigation, surveillance, and reports on foodborne viral illnesses, are needed in order to develop more accurate measures to detect the presence and pathogenesis of viral infection with detailed descriptions. Moreover, molecular epidemiology and surveillance of food samples may help analysis of public health hazards associated with exposure to foodborne viruses. In this present review, we discuss different aspects of foodborne viral contamination and its impact on human health. This review also aims to improve understanding of foodborne viral infections as major causes of human illness as well as provide descriptions of their control and prevention strategies and rapid detection by advanced molecular techniques. Further, a brief description of methods available for the detection of viruses in food and related matrices is provided.

Kinetics of viral shedding provide insights into the epidemiology of viral hemorrhagic septicemia in Pacific herring

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Hershberger, Paul K.; Gregg, Jacob L.; Winton, James R.; Grady, Courtney; Collins, Rachael

2010-01-01

Losses from infectious diseases are an important component of natural mortality among marine fish species, but factors controlling the ecology of these diseases and their potential responses to anthropogenic changes are poorly understood. We used viral hemorrhagic septicemia virus (VHSV) and a laboratory stock of Pacific herring Clupea pallasii to investigate the kinetics of viral shedding and its effect on disease transmission and host mortality. Outbreaks of acute disease, accompanied by mortality and viral shedding, were initiated after waterborne exposure of herring to concentrations of VHSV as low as 101 plaque-forming units (pfu) ml–1. Shed virus in flow-through tanks was first detected 4 to 5 d post-exposure, peaked after 6 to 10 d, and was no longer detected after 16 d. Shedding rates, calculated from density, flow and waterborne virus titer reached 1.8 to 5.0 × 108 pfu fish–1 d–1. Onset of viral shedding was dose-dependent and preceded initial mortality by 2 d. At 21 d, cumulative mortality in treatment groups ranged from 81 to 100% and was dependent not on challenge dose, but on the kinetics and level of viral shedding by infected fish in the tank. Possible consequences of the viral shedding and disease kinetics are discussed in the context of epizootic initiation and perpetuation among populations of wild Pacific herring.

Ultrasonographic study of gallbladder wall thickness in acute viral hepatitis

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Lim, Jin Sook; Kim, Kyung Jung; Park, Yang Hee; Kang, Ik Won; Yoon, Jong Sup [Hanyang Sacred Heart Hospital, Hallym University Medical Center, Seoul (Korea, Republic of)

1984-09-15

Prospective study of gallbladder wall thickness by ultrasonography was performed in 38 patients of acute viral hepatitis and 50 normal subjects as a control group from June 1983 to April 1984. The results were as follows; 1. In normal population, the range of gallbladder wall thickness is from 1 mm to 3 mm with peak incidence in 2 mm (66%, 33 case). Mean thickness of gallbladder wall is about 1.9 {+-} 0.6 mm. 2. In acute viral hepatitis, the range of gallbladder wall thickness is from 2 mm to 8 mm with peak incidence in 3 mm (34%, 13 case), second peak in 4 mm (29%, 11 case). Mean thickness of gallbladder wall is about 3.6 {+-} 1.6 mm, which is thicker than normal with statistical significance. (p<0.005) 3. In acute viral hepatitis, the mean thickness of gallbladder wall is about 4.4 {+-} 1.8 mm in the group of SGOT/SGPT level above 400 IU, and 2.8 {+-} 0.8 mm in the group of SGOT/ SGPT level below 400 IU. This difference is significant statistically. (p<0.05)

Ultrasonographic study of gallbladder wall thickness in acute viral hepatitis

International Nuclear Information System (INIS)

Lim, Jin Sook; Kim, Kyung Jung; Park, Yang Hee; Kang, Ik Won; Yoon, Jong Sup

1984-01-01

Prospective study of gallbladder wall thickness by ultrasonography was performed in 38 patients of acute viral hepatitis and 50 normal subjects as a control group from June 1983 to April 1984. The results were as follows; 1. In normal population, the range of gallbladder wall thickness is from 1 mm to 3 mm with peak incidence in 2 mm (66%, 33 case). Mean thickness of gallbladder wall is about 1.9 ± 0.6 mm. 2. In acute viral hepatitis, the range of gallbladder wall thickness is from 2 mm to 8 mm with peak incidence in 3 mm (34%, 13 case), second peak in 4 mm (29%, 11 case). Mean thickness of gallbladder wall is about 3.6 ± 1.6 mm, which is thicker than normal with statistical significance. (p<0.005) 3. In acute viral hepatitis, the mean thickness of gallbladder wall is about 4.4 ± 1.8 mm in the group of SGOT/SGPT level above 400 IU, and 2.8 ± 0.8 mm in the group of SGOT/ SGPT level below 400 IU. This difference is significant statistically. (p<0.05)

Hepatitis A viral load in relation to severity of the infection.

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Fujiwara, Keiichi; Kojima, Hiroshige; Yasui, Shin; Okitsu, Koichiro; Yonemitsu, Yutaka; Omata, Masao; Yokosuka, Osamu

2011-02-01

A correlation between hepatitis A virus (HAV) genomes and the clinical severity of hepatitis A has not been established. The viral load in sera of hepatitis A patients was examined to determine the possible association between hepatitis A severity and HAV replication. One hundred sixty-four serum samples from 91 Japanese patients with sporadic hepatitis A, comprising 11 patients with fulminant hepatitis, 10 with severe acute hepatitis, and 70 with self-limited acute hepatitis, were tested for HAV RNA. The sera included 83 serial samples from 20 patients. Viral load was measured by real-time RT-PCR. The detection rates of HAV RNA from fulminant, severe acute, and acute hepatitis were 10/11 (91%), 10/10 (100%), and 55/70 (79%), respectively. Mean values of HAV RNA at admission were 3.48 ± 1.30 logcopies/ml in fulminant, 4.19 ± 1.03 in severe acute, and 2.65 ± 1.64 in acute hepatitis. Patients with severe infection such as fulminant hepatitis and severe acute hepatitis had higher initial viral load than patients with less severe infection (P hepatitis after clinical onset (P = 0.19). HAV RNA was detectable quantitatively in the majority of the sera of hepatitis A cases during the early convalescent phase by real-time PCR. Higher initial viral replication was found in severely infected patients. An excessive host immune response might follow, reducing the viral load rapidly as a result of the destruction of large numbers of HAV-infected hepatocytes, and in turn severe disease might be induced. 2010 Wiley-Liss, Inc.

Virus del dengue: estructura y ciclo viral Dengue virus: structure and viral cycle

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Myriam L Velandia

2011-03-01

Full Text Available El virus del dengue (DENV es el agente causal de la enfermedad conocida como dengue, que es la principal enfermedad viral transmitida por artrópodos en el mundo. El DENV es un flavivirus que ingresa por endocitosis y se replica en el citoplasma de la célula infectada, originando tres proteínas estructurales y siete proteínas no estructurales, sobre las cuales se conocen sólo algunas de sus funciones en la replicación viral o en la infección. El ciclo viral que ocurre en las células infectadas hasta ahora está comenzando a aclararse y su conocimiento permitirá en el futuro próximo diseñar racionalmente moléculas que lo intervengan y eviten la replicación del virus. Durante la infección, el individuo puede presentar fiebre indiferenciada o, en otros casos, puede presentar un proceso generalizado de activación de la respuesta inmunitaria innata y adquirida, lo cual provoca la liberación de factores inflamatorios solubles que alteran la fisiología de los tejidos, principalmente el endotelio, conllevando al desarrollo de manifestaciones clínicas graves. Aunque se ha identificado un gran número de factores del individuo asociados al desarrollo de la enfermedad por DENV, queda por identificar el papel de las diferentes proteínas virales en la patogenia de la enfermedad. En la presente revisión, se presenta una breve actualización sobre la estructura y biología del DENV, de su ciclo viral intracelular y, finalmente, se introducen algunos conceptos sobre la inmunopatogenia de la enfermedad producida por este agente.Dengue virus (DENV is responsible for the clinical entity known as dengue that is a great concern for economy and public health of tropical countries. This flavivirus is a single strand RNA virus that after their translation and replication in host cells produces three structural and seven non-structural proteins with specific function in replication or cell binding process that we will describe here. Intracellular

Phage and Nucleocytoplasmic Large Viral Sequences Dominate Coral Viromes from the Arabian Gulf.

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Mahmoud, Huda; Jose, Liny

2017-01-01

Corals that naturally thrive under extreme conditions are gaining increasing attention due to their importance as living models to understand the impact of global warming on world corals. Here, we present the first metagenomic study of viral communities in corals thriving in a thermally variable water body in which the temperature fluctuates between 11 and 39°C in different seasons. The viral assemblages of two of the most abundant massive ( Porites harrisoni ) and branching ( Acropora downingi ) corals in offshore and inshore reef systems in the northern Arabian Gulf were investigated. Samples were collected from five reef systems during summer, autumn and winter of 2011/2012. The two coral viromes contain 12 viral families, including 10 dsDNA viral families [Siphoviridae, Podoviridae, Myoviridae, Phycodnaviridae, Baculoviridae, Herpesviridae, Adenoviridae, Alloherpesviridae, Mimiviridae and one unclassified family], one-ssDNA viral family (Microviridae) and one RNA viral family (Retroviridae). Overall, sequences significantly similar to Podoviridae were the most abundant in the P. harrisoni and A. downingi viromes. Various morphological types of virus-like particles (VLPs) were confirmed in the healthy coral tissue by transmission electron microscopy, including large tailless VLPs and electron-dense core VLPs. Tailed bacteriophages were isolated from coral tissue using a plaque assay. Higher functional gene diversity was recorded in A. downingi than in P. harrisoni , and comparative metagenomics revealed that the Gulf viral assemblages are functionally distinct from Pacific Ocean coral viral communities.

Phage and Nucleocytoplasmic Large Viral Sequences Dominate Coral Viromes from the Arabian Gulf

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Huda Mahmoud

2017-10-01

Full Text Available Corals that naturally thrive under extreme conditions are gaining increasing attention due to their importance as living models to understand the impact of global warming on world corals. Here, we present the first metagenomic study of viral communities in corals thriving in a thermally variable water body in which the temperature fluctuates between 11 and 39°C in different seasons. The viral assemblages of two of the most abundant massive (Porites harrisoni and branching (Acropora downingi corals in offshore and inshore reef systems in the northern Arabian Gulf were investigated. Samples were collected from five reef systems during summer, autumn and winter of 2011/2012. The two coral viromes contain 12 viral families, including 10 dsDNA viral families [Siphoviridae, Podoviridae, Myoviridae, Phycodnaviridae, Baculoviridae, Herpesviridae, Adenoviridae, Alloherpesviridae, Mimiviridae and one unclassified family], one-ssDNA viral family (Microviridae and one RNA viral family (Retroviridae. Overall, sequences significantly similar to Podoviridae were the most abundant in the P. harrisoni and A. downingi viromes. Various morphological types of virus-like particles (VLPs were confirmed in the healthy coral tissue by transmission electron microscopy, including large tailless VLPs and electron-dense core VLPs. Tailed bacteriophages were isolated from coral tissue using a plaque assay. Higher functional gene diversity was recorded in A. downingi than in P. harrisoni, and comparative metagenomics revealed that the Gulf viral assemblages are functionally distinct from Pacific Ocean coral viral communities.

Immunological and molecular epidemiological characteristics of acute and fulminant viral hepatitis A

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2011-01-01

Background Hepatitis A virus is an infection of liver; it is hyperendemic in vast areas of the world including India. In most cases it causes an acute self limited illness but rarely fulminant. There is growing concern about change in pattern from asymptomatic childhood infection to an increased incidence of symptomatic disease in the adult population. Objective In-depth analysis of immunological, viral quantification and genotype of acute and fulminant hepatitis A virus. Methods Serum samples obtained from 1009 cases of suspected acute viral hepatitis was employed for different biochemical and serological examination. RNA was extracted from blood serum, reverse transcribed into cDNA and amplified using nested PCR for viral quantification, sequencing and genotyping. Immunological cell count from freshly collected whole blood was carried out by fluorescence activated cell sorter. Results Fulminant hepatitis A was mostly detected with other hepatic viruses. CD8+ T cells count increases in fulminant hepatitis to a significantly high level (P = 0.005) compared to normal healthy control. The immunological helper/suppressor (CD4+/CD8+) ratio of fulminant hepatitis was significantly lower compared to acute cases. The serologically positive patients were confirmed by RT-PCR and total of 72 (69.2%) were quantified and sequenced. The average quantitative viral load of fulminant cases was significantly higher (P hepatitis A. Phylogenetic analysis of acute and fulminant hepatitis A confirmed genotypes IIIA as predominant against IA with no preference of disease severity. PMID:21605420

Boronic acid-modified lipid nanocapsules: a novel platform for the highly efficient inhibition of hepatitis C viral entry

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Khanal, Manakamana; Barras, Alexandre; Vausselin, Thibaut; Fénéant, Lucie; Boukherroub, Rabah; Siriwardena, Aloysius; Dubuisson, Jean; Szunerits, Sabine

2015-01-01

The search for viral entry inhibitors that selectively target viral envelope glycoproteins has attracted increasing interest in recent years. Amongst the handful of molecules reported to show activity as hepatitis C virus (HCV) entry inhibitors are a variety of glycan-binding proteins including the lectins, cyanovirin-N (CV-N) and griffithsin. We recently demonstrated that boronic acid-modified nanoparticles are able to reduce HCV entry through a similar mechanism to that of lectins. A major obstacle to any further development of these nanostructures as viral entry inhibitors is their only moderate maximal inhibition potential. In the present study, we report that lipid nanocapsules (LNCs), surface-functionalized with amphiphilic boronic acid (BA) through their post-insertion into the semi-rigid shell of the LNCs, are indeed far superior as HCV entry inhibitors when compared with previously reported nanostructures. These 2nd generation particles (BA-LNCs) are shown to prevent HCV infection in the micromolar range (IC50 = 5.4 μM of BA moieties), whereas the corresponding BA monomers show no significant effects even at the highest analyzed concentration (20 μM). The new BA-LNCs are the most promising boronolectin-based HCV entry inhibitors reported to date and are thus observed to show great promise in the development of a pseudolectin-based therapeutic agent.The search for viral entry inhibitors that selectively target viral envelope glycoproteins has attracted increasing interest in recent years. Amongst the handful of molecules reported to show activity as hepatitis C virus (HCV) entry inhibitors are a variety of glycan-binding proteins including the lectins, cyanovirin-N (CV-N) and griffithsin. We recently demonstrated that boronic acid-modified nanoparticles are able to reduce HCV entry through a similar mechanism to that of lectins. A major obstacle to any further development of these nanostructures as viral entry inhibitors is their only moderate maximal

APOBEC3 Interference during Replication of Viral Genomes

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Luc Willems

2015-06-01

Full Text Available Co-evolution of viruses and their hosts has reached a fragile and dynamic equilibrium that allows viral persistence, replication and transmission. In response, infected hosts have developed strategies of defense that counteract the deleterious effects of viral infections. In particular, single-strand DNA editing by Apolipoprotein B Editing Catalytic subunits proteins 3 (APOBEC3s is a well-conserved mechanism of mammalian innate immunity that mutates and inactivates viral genomes. In this review, we describe the mechanisms of APOBEC3 editing during viral replication, the viral strategies that prevent APOBEC3 activity and the consequences of APOBEC3 modulation on viral fitness and host genome integrity. Understanding the mechanisms involved reveals new prospects for therapeutic intervention.

Which adherence measure - self-report, clinician recorded or pharmacy refill - is best able to predict detectable viral load in a public ART programme without routine plasma viral load monitoring?

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Mekuria, Legese A; Prins, Jan M; Yalew, Alemayehu W; Sprangers, Mirjam A G; Nieuwkerk, Pythia T

2016-07-01

Combination antiretroviral therapy (cART) suppresses viral replication to an undetectable level if a sufficiently high level of adherence is achieved. We investigated which adherence measurement best distinguishes between patients with and without detectable viral load in a public ART programme without routine plasma viral load monitoring. We randomly selected 870 patients who started cART between May 2009 and April 2012 in 10 healthcare facilities in Addis Ababa, Ethiopia. Six hundred and sixty-four (76.3%) patients who were retained in HIV care and were receiving cART for at least 6 months were included and 642 had their plasma HIV-1 RNA concentration measured. Patients' adherence to cART was assessed according to self-report, clinician recorded and pharmacy refill measures. Multivariate logistic regression model was fitted to identify the predictors of detectable viremia. Model accuracy was evaluated by computing the area under the receiver operating characteristic (ROC) curve. A total of 9.2% and 5.5% of the 642 patients had a detectable viral load of ≥40 and ≥400 RNA copies/ml, respectively. In the multivariate analyses, younger age, lower CD4 cell count at cART initiation, being illiterate and widowed, and each of the adherence measures were significantly and independently predictive of having ≥400 RNA copies/ml. The ROC curve showed that these variables altogether had a likelihood of more than 80% to distinguish patients with a plasma viral load of ≥400 RNA copies/ml from those without. Adherence to cART was remarkably high. Self-report, clinician recorded and pharmacy refill non-adherence were all significantly predictive of detectable viremia. The choice for one of these methods to detect non-adherence and predict a detectable viral load can therefore be based on what is most practical in a particular setting. © 2016 John Wiley & Sons Ltd.

Self-Perceived Viral Load and Sexual Risk Behavior Among Known HIV-Positive MSM in San Francisco, 2014.

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Guigayoma, John; Chen, Yea-Hung; Snowden, Jonathan M; Santos, Glenn-Milo; Hecht, Jennifer; Raymond, H Fisher

2017-07-01

Self-perceived viral suppression status among men who have sex with men (MSM) may impact HIV risk transmission behaviors. We conducted a 2014 cross-sectional survey of MSM in San Francisco and assessed differences in sexual risk behavior among known HIV-positive MSM based on viral suppression of HIV. We collected demographics, self-perceived viral load status, and sexual risk behavior and tested for viral load levels through laboratory assays. Men were categorized in a hierarchical schema of sexual risk behavior categories based on responses to questions regarding recent partners' HIV status, condom use, and sexual positioning. We used Fisher exact tests to assess for differences based on self-perceived viral load status. Out of a sample of 96 known HIV-positive men, 59 men self-reported an undetectable HIV viral load and 9 men self-reported a detectable viral load consented to confirmatory laboratory testing. The sample of self-reported undetectable men had gradually larger proportions of higher-risk sexual practices, whereas the sample of detectable men was evenly distributed across sexual practices. This association was not statistically significant (P = 0.91). Self-perceived viral suppression may influence sexual practices of known HIV-positive MSM, but small sample size, especially within the detectable category, hinders our ability to determine statistical significance. More research is necessary to assess how HIV-positive men account for viral load in sexual decision-making practices, and this research may inform resource allocation and clinical recommendations to maintain the health of MSM populations.

Use of profile hidden Markov models in viral discovery: current insights

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Reyes A

2017-07-01

Full Text Available Alejandro Reyes,1–3 João Marcelo P Alves,4 Alan Mitchell Durham,5 Arthur Gruber4 1Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia; 2Department of Pathology and Immunology, Center for Genome Sciences and Systems Biology, Washington University in Saint Louis, St Louis, MO, USA; 3Max Planck Tandem Group in Computational Biology, Universidad de los Andes, Bogotá, Colombia; 4Department of Parasitology, Institute of Biomedical Sciences, 5Department of Computer Science, Institute of Mathematics and Statistics, Universidade de São Paulo, São Paulo, Brazil Abstract: Sequence similarity searches are the bioinformatic cornerstone of molecular sequence analysis for all domains of life. However, large amounts of divergence between organisms, such as those seen among viruses, can significantly hamper analyses. Profile hidden Markov models (profile HMMs are among the most successful approaches for dealing with this problem, which represent an invaluable tool for viral identification efforts. Profile HMMs are statistical models that convert information from a multiple sequence alignment into a set of probability values that reflect position-specific variation levels in all members of evolutionarily related sequences. Since profile HMMs represent a wide spectrum of variation, these models show higher sensitivity than conventional similarity methods such as BLAST for the detection of remote homologs. In recent years, there has been an effort to compile viral sequences from different viral taxonomic groups into integrated databases, such as Prokaryotic Virus Orthlogous Groups (pVOGs and database of profile HMMs (vFam database, which provide functional annotation, multiple sequence alignments, and profile HMMs. Since these databases rely on viral sequences collected from GenBank and RefSeq, they suffer in variable extent from uneven taxonomic sampling, with low sequence representation of many viral groups, which affects the

The Pacific Ocean virome (POV: a marine viral metagenomic dataset and associated protein clusters for quantitative viral ecology.

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Bonnie L Hurwitz

Full Text Available Bacteria and their viruses (phage are fundamental drivers of many ecosystem processes including global biogeochemistry and horizontal gene transfer. While databases and resources for studying function in uncultured bacterial communities are relatively advanced, many fewer exist for their viral counterparts. The issue is largely technical in that the majority (often 90% of viral sequences are functionally 'unknown' making viruses a virtually untapped resource of functional and physiological information. Here, we provide a community resource that organizes this unknown sequence space into 27 K high confidence protein clusters using 32 viral metagenomes from four biogeographic regions in the Pacific Ocean that vary by season, depth, and proximity to land, and include some of the first deep pelagic ocean viral metagenomes. These protein clusters more than double currently available viral protein clusters, including those from environmental datasets. Further, a protein cluster guided analysis of functional diversity revealed that richness decreased (i from deep to surface waters, (ii from winter to summer, (iii and with distance from shore in surface waters only. These data provide a framework from which to draw on for future metadata-enabled functional inquiries of the vast viral unknown.

The Pacific Ocean virome (POV): a marine viral metagenomic dataset and associated protein clusters for quantitative viral ecology.

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Hurwitz, Bonnie L; Sullivan, Matthew B

2013-01-01

Bacteria and their viruses (phage) are fundamental drivers of many ecosystem processes including global biogeochemistry and horizontal gene transfer. While databases and resources for studying function in uncultured bacterial communities are relatively advanced, many fewer exist for their viral counterparts. The issue is largely technical in that the majority (often 90%) of viral sequences are functionally 'unknown' making viruses a virtually untapped resource of functional and physiological information. Here, we provide a community resource that organizes this unknown sequence space into 27 K high confidence protein clusters using 32 viral metagenomes from four biogeographic regions in the Pacific Ocean that vary by season, depth, and proximity to land, and include some of the first deep pelagic ocean viral metagenomes. These protein clusters more than double currently available viral protein clusters, including those from environmental datasets. Further, a protein cluster guided analysis of functional diversity revealed that richness decreased (i) from deep to surface waters, (ii) from winter to summer, (iii) and with distance from shore in surface waters only. These data provide a framework from which to draw on for future metadata-enabled functional inquiries of the vast viral unknown.

Viral-specific T-cell transfer from HSCT donor for the treatment of viral infections or diseases after HSCT.

Science.gov (United States)

Qian, C; Wang, Y; Reppel, L; D'aveni, M; Campidelli, A; Decot, V; Bensoussan, D

2018-02-01

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative option for treatment of some malignant and non-malignant hematological diseases. However, post-HSCT patients are severely immunocompromised and susceptible to viral infections, which are a major cause of morbidity and mortality. Although antiviral agents are now available for most types of viral infections, they are not devoid of side effects and their efficacy is limited when there is no concomitant antiviral immune reconstitution. In recent decades, adoptive transfer of viral-specific T cells (VSTs) became an alternative treatment for viral infection after HSCT. However, two major issues are concerned in VST transfer: the risk of GVHD and antiviral efficacy. We report an exhaustive review of the published studies that focus on prophylactic and/or curative therapy by donor VST transfer for post-HSCT common viral infections. A low incidence of GVHD and a good antiviral efficacy was observed after adoptive transfer of VSTs from HSCT donor. Viral-specific T-cell transfer is a promising approach for a broad clinical application. Nevertheless, a randomized controlled study in a large cohort of patients comparing antiviral treatment alone to antiviral treatment combined with VSTs is still needed to demonstrate efficacy and safety.

Viral membrane fusion

International Nuclear Information System (INIS)

Harrison, Stephen C.

2015-01-01

Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. - Highlights: • Viral fusion proteins overcome the high energy barrier to lipid bilayer merger. • Different molecular structures but the same catalytic mechanism. • Review describes properties of three known fusion-protein structural classes. • Single-virion fusion experiments elucidate mechanism

Viral membrane fusion

Energy Technology Data Exchange (ETDEWEB)

Harrison, Stephen C., E-mail: harrison@crystal.harvard.edu

2015-05-15

Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. - Highlights: • Viral fusion proteins overcome the high energy barrier to lipid bilayer merger. • Different molecular structures but the same catalytic mechanism. • Review describes properties of three known fusion-protein structural classes. • Single-virion fusion experiments elucidate mechanism.

Carbohydrate-Based Ice Recrystallization Inhibitors Increase Infectivity and Thermostability of Viral Vectors

Science.gov (United States)

Ghobadloo, Shahrokh M.; Balcerzak, Anna K.; Gargaun, Ana; Muharemagic, Darija; Mironov, Gleb G.; Capicciotti, Chantelle J.; Briard, Jennie G.; Ben, Robert N.; Berezovski, Maxim V.

2014-07-01

The inability of vaccines to retain sufficient thermostability has been an obstacle to global vaccination programs. To address this major limitation, we utilized carbohydrate-based ice recrystallization inhibitors (IRIs) to eliminate the cold chain and stabilize the potency of Vaccinia virus (VV), Vesicular Stomatitis virus (VSV) and Herpes virus-1 (HSV-1). The impact of these IRIs was tested on the potency of the viral vectors using a plaque forming unit assay following room temperature storage, cryopreservation with successive freeze-thaw cycles and lyophilization. Viral potency after storage with all three conditions demonstrated that N-octyl-gluconamide (NOGlc) recovered the infectivity of shelf stored VV, 5.6 Log10 PFU mL-1 during 40 days, and HSV-1, 2.7 Log10 PFU mL-1 during 9 days. Carbon-linked antifreeze glycoprotein analogue ornithine-glycine-glycine-galactose (OGG-Gal) increases the recovery of VV and VSV more than 1 Log10 PFU mL-1 after 10 freeze-thaw cycles. In VSV, cryostorage with OGG-Gal maintains high infectivity and reduces temperature-induced aggregation of viral particles by 2 times that of the control. In total, OGG-Gal and NOGlc preserve virus potency during cryostorage. Remarkably, NOGlc has potential to eliminate the cold chain and permit room temperature storage of viral vectors.

Viral Advertising on Facebook in Vietnam

OpenAIRE

Tran, Phuong

2014-01-01

The purpose of this thesis is to explore which factors affect the effectiveness of viral advertising on Facebook in Vietnam. The quantitative research method is applied in this research and the sample is Vietnamese Facebook users. After the data analysis stage using SPSS, it became clear that weak ties, perceptual affinity and emotions have an impact on the effectiveness of viral advertising. The results provide a pratical implication of how to make an Ad which can go viral on Facebook. Moreo...

Cardiac Function Remains Impaired Despite Reversible Cardiac Remodeling after Acute Experimental Viral Myocarditis

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Peter Moritz Becher

2017-01-01

Full Text Available Background. Infection with Coxsackievirus B3 induces myocarditis. We aimed to compare the acute and chronic phases of viral myocarditis to identify the immediate effects of cardiac inflammation as well as the long-term effects after resolved inflammation on cardiac fibrosis and consequently on cardiac function. Material and Methods. We infected C57BL/6J mice with Coxsackievirus B3 and determined the hemodynamic function 7 as well as 28 days after infection. Subsequently, we analyzed viral burden and viral replication in the cardiac tissue as well as the expression of cytokines and matrix proteins. Furthermore, cardiac fibroblasts were infected with virus to investigate if viral infection alone induces profibrotic signaling. Results. Severe cardiac inflammation was determined and cardiac fibrosis was consistently colocalized with inflammation during the acute phase of myocarditis. Declined cardiac inflammation but no significantly improved hemodynamic function was observed 28 days after infection. Interestingly, cardiac fibrosis declined to basal levels as well. Both cardiac inflammation and fibrosis were reversible, whereas the hemodynamic function remains impaired after healed viral myocarditis in C57BL/6J mice.

Viral etiology and clinical profiles of children with severe acute respiratory infections in China.

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Chen Zhang

Full Text Available No comprehensive analysis is available on the viral etiology and clinical characterization among children with severe acute respiratory infection (SARI in China during 2009 H1N1 pandemic and post-pandemic period.Cohort of 370 hospitalized children (1 to 72 months with SARI from May 2008 to March 2010 was enrolled in this study. Nasopharyngeal aspirate (NPA specimens were tested by a commercial assay for 18 respiratory viral targets. The viral distribution and its association with clinical character were statistically analyzed.Viral pathogen was detected in 350 (94.29% of children with SARI. Overall, the most popular viruses were: enterovirus/rhinovirus (EV/RV (54.05%, respiratory syncytial virus (RSV (51.08%, human bocavirus (BoCA (33.78%, human parainfluenzaviruse type 3 (PIV3 (15.41%, and adenovirus (ADV (12.97%. Pandemic H1N1 was the dominant influenza virus (IFV but was only detected in 20 (5.41% of children. Moreover, detection rate of RSV and human metapneumovirus (hMPV among suburb participants were significantly higher than that of urban area (P<0.05. Incidence of VSARI among suburb participants was also significant higher, especially among those of 24 to 59 months group (P<0.05.Piconaviruses (EV/RV and paramyxoviruses are the most popular viral pathogens among children with SARI in this study. RSV and hMPV significantly increase the risk of SARI, especially in children younger than 24 months. Higher incidence of VSARI and more susceptibilities to RSV and hMPV infections were found in suburban patients.

Significance of host cell kinases in herpes simplex virus type 1 egress and lamin-associated protein disassembly from the nuclear lamina

International Nuclear Information System (INIS)

Leach, Natalie R.; Roller, Richard J.

2010-01-01

The nuclear lamina is thought to be a steric barrier to the herpesvirus capsid. Disruption of the lamina accompanied by phosphorylation of lamina proteins is a conserved feature of herpesvirus infection. In HSV-1-infected cells, protein kinase C (PKC) alpha and delta isoforms are recruited to the nuclear membrane and PKC delta has been implicated in phosphorylation of emerin and lamin B. We tested two critical hypotheses about the mechanism and significance of lamina disruption. First, we show that chemical inhibition of all PKC isoforms reduced viral growth five-fold and inhibited capsid egress from the nucleus. However, specific inhibition of either conventional PKCs or PKC delta does not inhibit viral growth. Second, we show hyperphosphorylation of emerin by viral and cellular kinases is required for its disassociation from the lamina. These data support hypothesis that phosphorylation of lamina components mediates lamina disruption during HSV nuclear egress.

Diabetes mellitus and renal involvement in chronic viral liver disease.

Science.gov (United States)

Iovanescu, V F; Streba, C T; Ionescu, M; Constantinescu, A F; Vere, C C; Rogoveanu, I; Moța, E

2015-01-01

significant association between diabetes mellitus and chronic viral liver disease induced by hepatitis C virus. Glomerulonephritis was the most common type of renal disease in both hepatitis patients and in those with cirrhosis. Glomerular injury was strongly correlated with the presence of hepatitis C virus than with hepatitis B virus. A connection between diabetes mellitus and hepatocellular carcinoma could not be established.

Viral Inhibition of Bacterial Phagocytosis by Human Macrophages: Redundant Role of CD36.

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Grace E Cooper

Full Text Available Macrophages are essential to maintaining lung homoeostasis and recent work has demonstrated that influenza-infected lung macrophages downregulate their expression of the scavenger receptor CD36. This receptor has also been shown to be involved in phagocytosis of Streptococcus pneumoniae, a primary agent associated with pneumonia secondary to viral infection. The aim of this study was to investigate the role of CD36 in the effects of viral infection on macrophage phagocytic function. Human monocyte-derived macrophages (MDM were exposed to H3N2 X31 influenza virus, M37 respiratory syncytial virus (RSV or UV-irradiated virus. No infection of MDM was seen upon exposure to UV-irradiated virus but incubation with live X31 or M37 resulted in significant levels of viral detection by flow cytometry or RT-PCR respectively. Infection resulted in significantly diminished uptake of S. pneumoniae by MDM and significantly decreased expression of CD36 at both the cell surface and mRNA level. Concurrently, there was a significant increase in IFNβ gene expression in response to infection and we observed a significant decrease in bacterial phagocytosis (p = 0.031 and CD36 gene expression (p = 0.031 by MDM cultured for 24 h in 50IU/ml IFNβ. Knockdown of CD36 by siRNA resulted in decreased phagocytosis, but this was mimicked by transfection reagent alone. When MDM were incubated with CD36 blocking antibodies no effect on phagocytic ability was observed. These data indicate that autologous IFNβ production by virally-infected cells can inhibit bacterial phagocytosis, but that decreased CD36 expression by these cells does not play a major role in this functional deficiency.

HIV Viral Load: MedlinePlus Lab Test Information

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... this page: https://medlineplus.gov/labtests/hivviralload.html HIV Viral Load To use the sharing features on this page, please enable JavaScript. What is an HIV Viral Load? An HIV viral load is a ...

Analysis of the viral progeny during the indirect recombinogenesis of the lambda bacteriophage; Analisis de la progenie viral durante la recombinogenesis indirecta del bacteriofago lambda

Energy Technology Data Exchange (ETDEWEB)

Alcantara D, D [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

1993-12-15

In this work the effect of the UV irradiation on the number of cells that follow the lytic via of the phage is determined, as well as the production of total particles and recombinants in irradiated individual cells and not irradiated with light UV. The results show that the indirect recombinogenesis of lambda is caused by a so much increment in the number of recombinant phages for cells like in the number of cells in those that happen events of viral recombination, without any significant effect on the number of bacteria that follow the lytic via of viral development. (Author)

TLR3 signaling is either protective or pathogenic for the development of Theiler's virus-induced demyelinating disease depending on the time of viral infection

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Jin Young-Hee

2011-12-01

Full Text Available Abstract Background We have previously shown that toll-like receptor 3 (TLR3-mediated signaling plays an important role in the induction of innate cytokine responses to Theiler's murine encephalomyelitis virus (TMEV infection. In addition, cytokine levels produced after TMEV infection are significantly higher in the glial cells of susceptible SJL mice compared to those of resistant C57BL/6 mice. However, it is not known whether TLR3-mediated signaling plays a protective or pathogenic role in the development of demyelinating disease. Methods SJL/J and B6;129S-Tlr3tm1Flv/J (TLR3KO-B6 mice, and TLR3KO-SJL mice that TLR3KO-B6 mice were backcrossed to SJL/J mice for 6 generations were infected with Theiler's murine encephalomyelitis virus (2 × 105 PFU with or without treatment with 50 μg of poly IC. Cytokine production and immune responses in the CNS and periphery of infected mice were analyzed. Results We investigated the role of TLR3-mediated signaling in the protection and pathogenesis of TMEV-induced demyelinating disease. TLR3KO-B6 mice did not develop demyelinating disease although they displayed elevated viral loads in the CNS. However, TLR3KO-SJL mice displayed increased viral loads and cellular infiltration in the CNS, accompanied by exacerbated development of demyelinating disease, compared to the normal littermate mice. Late, but not early, anti-viral CD4+ and CD8+ T cell responses in the CNS were compromised in TLR3KO-SJL mice. However, activation of TLR3 with poly IC prior to viral infection also exacerbated disease development, whereas such activation after viral infection restrained disease development. Activation of TLR3 signaling prior to viral infection hindered the induction of protective IFN-γ-producing CD4+ and CD8+ T cell populations. In contrast, activation of these signals after viral infection improved the induction of IFN-γ-producing CD4+ and CD8+ T cells. In addition, poly IC-pretreated mice displayed elevated PDL-1 and

Expression of a humanized viral 2A-mediated lux operon efficiently generates autonomous bioluminescence in human cells.

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Tingting Xu

Full Text Available Expression of autonomous bioluminescence from human cells was previously reported to be impossible, suggesting that all bioluminescent-based mammalian reporter systems must therefore require application of a potentially influential chemical substrate. While this was disproven when the bacterial luciferase (lux cassette was demonstrated to function in a human cell, its expression required multiple genetic constructs, was functional in only a single cell type, and generated a significantly reduced signal compared to substrate-requiring systems. Here we investigate the use of a humanized, viral 2A-linked lux genetic architecture for the efficient introduction of an autobioluminescent phenotype across a variety of human cell lines.The lux cassette was codon optimized and assembled into a synthetic human expression operon using viral 2A elements as linker regions. Human kidney, breast cancer, and colorectal cancer cell lines were both transiently and stably transfected with the humanized operon and the resulting autobioluminescent phenotype was evaluated using common imaging instrumentation. Autobioluminescent cells were screened for cytotoxic effects resulting from lux expression and their utility as bioreporters was evaluated through the demonstration of repeated monitoring of single populations over a prolonged period using both a modified E-SCREEN assay for estrogen detection and a classical cytotoxic compound detection assay for the antibiotic Zeocin. Furthermore, the use of self-directed bioluminescent initiation in response to target detection was assessed to determine its amenability towards deployment as fully autonomous sensors. In all cases, bioluminescent measurements were supported with traditional genetic and transcriptomic evaluations.Our results demonstrate that the viral 2A-linked, humanized lux genetic architecture successfully produced autobioluminescent phenotypes in all cell lines tested without the induction of cytotoxicity

The double-stranded RNA-activated protein kinase mediates viral-induced encephalitis

International Nuclear Information System (INIS)

Scheuner, Donalyn; Gromeier, Matthias; Davies, Monique V.; Dorner, Andrew J.; Song Benbo; Patel, Rupali V.; Wimmer, Eckard J.; McLendon, Roger E.; Kaufman, Randal J.

2003-01-01

The double-stranded (ds) RNA-activated protein kinase (PKR) plays an important role in control of viral infections and cell growth. We have studied the role of PKR in viral infection in mice that are defective in the PKR signaling pathway. Transgenic mice were derived that constitutively express a trans-dominant-negative kinase-defective mutant PKR under control of the β-actin promoter. The trans-dominant-negative PKR mutant expressing transgenic mice do not have a detectable phenotype, similar to observations with PKR knock-out mice. The requirement for PKR in viral pathogenesis was studied by intracerebral infection of mice with a mouse-adapted poliovirus. Histopathological analysis revealed diffuse encephalomyelitis with severe inflammatory lesions throughout the central nervous system (CNS) in infected wild-type mice. In contrast, histopathological evaluation of virus-injected trans-dominant-negative PKR transgenic mice as well as PKR knock-out mice yielded no signs of tissue damage associated with inflammatory host responses. However, the virus did replicate in both models of PKR-deficient mice at a level equal to that observed in wild-type infected mice. Although the results indicate a clear difference in susceptibility to poliovirus-induced encephalitis, this difference manifests clinically as a slight delay in fatal neuropathy in trans-dominant-negative PKR transgenic and PKR knock-out animals. Our observations support the finding that viral-induced PKR activation may play a significant role in pathogenesis by mediating the host response to viral CNS infection. They support PKR to be an effective target to control tissue damage due to deleterious host responses to viral infection

IPNV with high and low virulence: host immune responses and viral mutations during infection

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Skjesol Astrid

2011-08-01

Full Text Available Abstract Background Infectious pancreatic necrosis virus (IPNV is an aquatic member of the Birnaviridae family that causes widespread disease in salmonids. IPNV is represented by multiple strains with markedly different virulence. Comparison of isolates reveals hyper variable regions (HVR, which are presumably associated with pathogenicity. However little is known about the rates and modes of sequence divergence and molecular mechanisms that determine virulence. Also how the host response may influence IPNV virulence is poorly described. Methods In this study we compared two field isolates of IPNV (NFH-Ar and NFH-El. The sequence changes, replication and mortality were assessed following experimental challenge of Atlantic salmon. Gene expression analyses with qPCR and microarray were applied to examine the immune responses in head kidney. Results Significant differences in mortality were observed between the two isolates, and viral load in the pancreas at 13 days post infection (d p.i. was more than 4 orders of magnitude greater for NFH-Ar in comparison with NFH-El. Sequence comparison of five viral genes from the IPNV isolates revealed different mutation rates and Ka/Ks ratios. A strong tendency towards non-synonymous mutations was found in the HRV of VP2 and in VP3. All mutations in VP5 produced precocious stop codons. Prior to the challenge, NFH-Ar and NFH-El possessed high and low virulence motifs in VP2, respectively. Nucleotide substitutions were noticed already during passage of viruses in CHSE-214 cells and their accumulation continued in the challenged fish. The sequence changes were notably directed towards low virulence. Co-ordinated activation of anti-viral genes with diverse functions (IFN-a1 and c, sensors - Rig-I, MDA-5, TLR8 and 9, signal transducers - Srk2, MyD88, effectors - Mx, galectin 9, galectin binding protein, antigen presentation - b2-microglobulin was observed at 13 d p.i. (NFH-Ar and 29 d p.i. (both isolates

[Prevalence and risk factors of respiratory viral infection in acute exacerbation of chronic obstructive pulmonary disease].

Science.gov (United States)

Du, X B; Ma, X; Gao, Y; Wen, L F; Li, J; Wang, Z Z; Liu, S

2017-04-12

Objective: To study the prevalence of respiratory viral infection in chronic obstructive pulmonary disease(COPD) exacerbations and to find the factors associated with susceptibility to viral infections. Methods: Eighty patients with exacerbations of COPD and 50 stable COPD patients were recruited. Nasopharyngeal swabs were tested for a range of 18 different respiratory viruses using PCR. Results: Among the COPD exacerbations, viral infection was detected in 18 episodes (22.5%) . The most common virus was rhinovirus (33.3%), followed by coronavirus(27.8%), parainfluenza(22.2%), metapneumovirus(11.1%) and influenza virus B(5.6%). The prevalence of viral infection was 8% in the stable COPD patients. In multivariate regression analysis fever was found to be significantly associated with viral infections in COPD exacerbations (Odds ratio 4.99, 95% CI 1.51-16.48, P =0.008). Conclusion: Viral respiratory pathogens were more often detected in respiratory specimens from hospitalized patients with AECOPD than those with stable COPD. Rhinovirus was the most common infecting agent identified. The symptom of fever was associated with viral detection.

Human Adenovirus Core Protein V Is Targeted by the Host SUMOylation Machinery To Limit Essential Viral Functions.

Science.gov (United States)

Freudenberger, Nora; Meyer, Tina; Groitl, Peter; Dobner, Thomas; Schreiner, Sabrina

2018-02-15

Human adenoviruses (HAdV) are nonenveloped viruses containing a linear, double-stranded DNA genome surrounded by an icosahedral capsid. To allow proper viral replication, the genome is imported through the nuclear pore complex associated with viral core proteins. Until now, the role of these incoming virion proteins during the early phase of infection was poorly understood. The core protein V is speculated to bridge the core and the surrounding capsid. It binds the genome in a sequence-independent manner and localizes in the nucleus of infected cells, accumulating at nucleoli. Here, we show that protein V contains conserved SUMO conjugation motifs (SCMs). Mutation of these consensus motifs resulted in reduced SUMOylation of the protein; thus, protein V represents a novel target of the host SUMOylation machinery. To understand the role of protein V SUMO posttranslational modification during productive HAdV infection, we generated a replication-competent HAdV with SCM mutations within the protein V coding sequence. Phenotypic analyses revealed that these SCM mutations are beneficial for adenoviral replication. Blocking protein V SUMOylation at specific sites shifts the onset of viral DNA replication to earlier time points during infection and promotes viral gene expression. Simultaneously, the altered kinetics within the viral life cycle are accompanied by more efficient proteasomal degradation of host determinants and increased virus progeny production than that observed during wild-type infection. Taken together, our studies show that protein V SUMOylation reduces virus growth; hence, protein V SUMOylation represents an important novel aspect of the host antiviral strategy to limit virus replication and thereby points to potential intervention strategies. IMPORTANCE Many decades of research have revealed that HAdV structural proteins promote viral entry and mainly physical stability of the viral genome in the capsid. Our work over the last years showed that this

Comparative analysis of measures of viral reservoirs in HIV-1 eradication studies.

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Susanne Eriksson

2013-02-01

Full Text Available HIV-1 reservoirs preclude virus eradication in patients receiving highly active antiretroviral therapy (HAART. The best characterized reservoir is a small, difficult-to-quantify pool of resting memory CD4(+ T cells carrying latent but replication-competent viral genomes. Because strategies targeting this latent reservoir are now being tested in clinical trials, well-validated high-throughput assays that quantify this reservoir are urgently needed. Here we compare eleven different approaches for quantitating persistent HIV-1 in 30 patients on HAART, using the original viral outgrowth assay for resting CD4(+ T cells carrying inducible, replication-competent viral genomes as a standard for comparison. PCR-based assays for cells containing HIV-1 DNA gave infected cell frequencies at least 2 logs higher than the viral outgrowth assay, even in subjects who started HAART during acute/early infection. This difference may reflect defective viral genomes. The ratio of infected cell frequencies determined by viral outgrowth and PCR-based assays varied dramatically between patients. Although strong correlations with the viral outgrowth assay could not be formally excluded for most assays, correlations achieved statistical significance only for integrated HIV-1 DNA in peripheral blood mononuclear cells and HIV-1 RNA/DNA ratio in rectal CD4(+ T cells. Residual viremia was below the limit of detection in many subjects and did not correlate with the viral outgrowth assays. The dramatic differences in infected cell frequencies and the lack of a precise correlation between culture and PCR-based assays raise the possibility that the successful clearance of latently infected cells may be masked by a larger and variable pool of cells with defective proviruses. These defective proviruses are detected by PCR but may not be affected by reactivation strategies and may not require eradication to accomplish an effective cure. A molecular understanding of the discrepancy

Exposure to electronic cigarettes impairs pulmonary anti-bacterial and anti-viral defenses in a mouse model.

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Thomas E Sussan

Full Text Available Electronic cigarettes (E-cigs have experienced sharp increases in popularity over the past five years due to many factors, including aggressive marketing, increased restrictions on conventional cigarettes, and a perception that E-cigs are healthy alternatives to cigarettes. Despite this perception, studies on health effects in humans are extremely limited and in vivo animal models have not been generated. Presently, we determined that E-cig vapor contains 7 x 10(11 free radicals per puff. To determine whether E-cig exposure impacts pulmonary responses in mice, we developed an inhalation chamber for E-cig exposure. Mice that were exposed to E-cig vapor contained serum cotinine concentrations that are comparable to human E-cig users. E-cig exposure for 2 weeks produced a significant increase in oxidative stress and moderate macrophage-mediated inflammation. Since, COPD patients are susceptible to bacterial and viral infections, we tested effects of E-cigs on immune response. Mice that were exposed to E-cig vapor showed significantly impaired pulmonary bacterial clearance, compared to air-exposed mice, following an intranasal infection with Streptococcus pneumonia. This defective bacterial clearance was partially due to reduced phagocytosis by alveolar macrophages from E-cig exposed mice. In response to Influenza A virus infection, E-cig exposed mice displayed increased lung viral titers and enhanced virus-induced illness and mortality. In summary, this study reports a murine model of E-cig exposure and demonstrates that E-cig exposure elicits impaired pulmonary anti-microbial defenses. Hence, E-cig exposure as an alternative to cigarette smoking must be rigorously tested in users for their effects on immune response and susceptibility to bacterial and viral infections.

Viral infections as potential triggers of type 1 diabetes

NARCIS (Netherlands)

van der Werf, Nienke; Kroese, Frans G. M.; Rozing, Jan; Hillebrands, Jan-Luuk

During the last decades, the incidence of type 1 diabetes (T1D) has increased significantly, reaching percentages of 3% annually worldwide. This increase suggests that besides genetical factors environmental perturbations (including viral infections) are also involved in the pathogenesis of T1D. T1D

Antiretroviral treatment, viral load of mothers & perinatal HIV transmission in Mumbai, India

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Swati P Ahir

2013-01-01

Full Text Available Background & objectives: Mother-to-child transmission (MTCT is the most significant route of HIV transmission in children below the age of 15 yr. In India, perinatal HIV transmission, even after treatment, accounts for 5.4 per cent of HIV cases. The present study was conducted to evaluate the efficacy of anti-retro viral therapy (ART or prophylactic treatment (PT to control maternal viral load in HIV positive women, and its effect on vertical HIV transmission to their infants. Methods: A total of 58 HIV positive women were enrolled at the time of delivery and their plasma samples were obtained within 24 h of delivery for estimation of viral load. Viral load analysis was completed in 38 women. Infants received single dose nevirapine within 2 h of birth and zidovudine for 6 wk. At the end of 18 month follow up, HIV positive or negative status was available in 28 infants. Results: Results revealed undetectable levels of viral load in 58.3 per cent of women with ART compared to 30.7 per cent of women with PT. No women on ART had viral load more than 10,000 copies/ml, whereas seven (26.9%, P=0.07 women receiving PT had this viral load. Median CD4 count of women on PT (483 cells/μl was high compared to the women on ART (289 cells/ μl. At the end of 18 months follow up, only two children were HIV positive, whose mothers were on PT. One had in utero transmission; infection detected within 48 h of delivery, while the other child was infected post partum as HIV was detected at six months follow up. Interpretation & conclusions: Women who received a single dose of nevirapine during delivery had higher levels of viral load than women on ART. Combination drug therapy for pregnant women is now a standard of care in most of the western countries; use of nevirapine monotherapy at the time of delivery in our settings is not effective in controlling viral load. This highlights initiation of ART in pregnant women to control their viral load and thus to inhibit

Endogenous viral elements in animal genomes.

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Aris Katzourakis

2010-11-01

Full Text Available Integration into the nuclear genome of germ line cells can lead to vertical inheritance of retroviral genes as host alleles. For other viruses, germ line integration has only rarely been documented. Nonetheless, we identified endogenous viral elements (EVEs derived from ten non-retroviral families by systematic in silico screening of animal genomes, including the first endogenous representatives of double-stranded RNA, reverse-transcribing DNA, and segmented RNA viruses, and the first endogenous DNA viruses in mammalian genomes. Phylogenetic and genomic analysis of EVEs across multiple host species revealed novel information about the origin and evolution of diverse virus groups. Furthermore, several of the elements identified here encode intact open reading frames or are expressed as mRNA. For one element in the primate lineage, we provide statistically robust evidence for exaptation. Our findings establish that genetic material derived from all known viral genome types and replication strategies can enter the animal germ line, greatly broadening the scope of paleovirological studies and indicating a more significant evolutionary role for gene flow from virus to animal genomes than has previously been recognized.

What makes a marketing campaing a viral success? : A descriptive model exploring the mechanisms of viral marketing

OpenAIRE

Stålnacke Larsson, Richard; Odén, Niklas

2011-01-01

What makes some marketing campaigns so immensely big and well known when they are marketed through social media or with a viral approach? How can a company reach out to customers through viral marketing and how can they make use of today’s social media to achieve it? In this article we will try to understand and further explore what a campaign have to accomplish in order to achieve a viral spread, using a descriptive model which uses a number of factors and terms necessary in order to properl...

Emerging Viral Diseases of Tomato Crops

NARCIS (Netherlands)

Hanssen, I.M.; Lapidot, M.; Thomma, B.P.H.J.

2010-01-01

Viral diseases are an important limiting factor in many crop production systems. Because antiviral products are not available, control strategies rely on genetic resistance or hygienic measures to prevent viral diseases, or on eradication of diseased crops to control such diseases. Increasing

Severe hindrance of viral infection propagation in spatially extended hosts.

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José A Capitán

Full Text Available The production of large progeny numbers affected by high mutation rates is a ubiquitous strategy of viruses, as it promotes quick adaptation and survival to changing environments. However, this situation often ushers in an arms race between the virus and the host cells. In this paper we investigate in depth a model for the dynamics of a phenotypically heterogeneous population of viruses whose propagation is limited to two-dimensional geometries, and where host cells are able to develop defenses against infection. Our analytical and numerical analyses are developed in close connection to directed percolation models. In fact, we show that making the space explicit in the model, which in turn amounts to reducing viral mobility and hindering the infective ability of the virus, connects our work with similar dynamical models that lie in the universality class of directed percolation. In addition, we use the fact that our model is a multicomponent generalization of the Domany-Kinzel probabilistic cellular automaton to employ several techniques developed in the past in that context, such as the two-site approximation to the extinction transition line. Our aim is to better understand propagation of viral infections with mobility restrictions, e.g., in crops or in plant leaves, in order to inspire new strategies for effective viral control.

Roles of the Picornaviral 3C Proteinase in the Viral Life Cycle and Host Cells

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Di Sun

2016-03-01

Full Text Available The Picornaviridae family comprises a large group of non-enveloped viruses that have a major impact on human and veterinary health. The viral genome contains one open reading frame encoding a single polyprotein that can be processed by viral proteinases. The crucial 3C proteinases (3Cpros of picornaviruses share similar spatial structures and it is becoming apparent that 3Cpro plays a significant role in the viral life cycle and virus host interaction. Importantly, the proteinase and RNA-binding activity of 3Cpro are involved in viral polyprotein processing and the initiation of viral RNA synthesis. In addition, 3Cpro can induce the cleavage of certain cellular factors required for transcription, translation and nucleocytoplasmic trafficking to modulate cell physiology for viral replication. Due to interactions between 3Cpro and these essential factors, 3Cpro is also involved in viral pathogenesis to support efficient infection. Furthermore, based on the structural conservation, the development of irreversible inhibitors and discovery of non-covalent inhibitors for 3Cpro are ongoing and a better understanding of the roles played by 3Cpro may provide insights into the development of potential antiviral treatments. In this review, the current knowledge regarding the structural features, multiple functions in the viral life cycle, pathogen host interaction, and development of antiviral compounds for 3Cpro is summarized.

Emerging infectious diseases with cutaneous manifestations: Viral and bacterial infections.

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Nawas, Zeena Y; Tong, Yun; Kollipara, Ramya; Peranteau, Andrew J; Woc-Colburn, Laila; Yan, Albert C; Lupi, Omar; Tyring, Stephen K

2016-07-01

Given increased international travel, immigration, and climate change, bacterial and viral infections that were once unrecognized or uncommon are being seen more frequently in the Western Hemisphere. A delay in diagnosis and treatment of these diseases can lead to significant patient morbidity and mortality. However, the diagnosis and management of these infections is fraught with a lack of consistency because there is a dearth of dermatology literature on the cutaneous manifestations of these infections. We review the epidemiology, cutaneous manifestations, diagnosis, and management of these emerging bacterial and viral diseases. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Selective expansion of viral variants following experimental transmission of a reconstituted feline immunodeficiency virus quasispecies.

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Brian J Willett

Full Text Available Following long-term infection with virus derived from the pathogenic GL8 molecular clone of feline immunodeficiency virus (FIV, a range of viral variants emerged with distinct modes of interaction with the viral receptors CD134 and CXCR4, and sensitivities to neutralizing antibodies. In order to assess whether this viral diversity would be maintained following subsequent transmission, a synthetic quasispecies was reconstituted comprising molecular clones bearing envs from six viral variants and its replicative capacity compared in vivo with a clonal preparation of the parent virus. Infection with either clonal (Group 1 or diverse (Group 2 challenge viruses, resulted in a reduction in CD4+ lymphocytes and an increase in CD8+ lymphocytes. Proviral loads were similar in both study groups, peaking by 10 weeks post-infection, a higher plateau (set-point being achieved and maintained in study Group 1. Marked differences in the ability of individual viral variants to replicate were noted in Group 2; those most similar to GL8 achieved higher viral loads while variants such as the chimaeras bearing the B14 and B28 Envs grew less well. The defective replication of these variants was not due to suppression by the humoral immune response as virus neutralising antibodies were not elicited within the study period. Similarly, although potent cellular immune responses were detected against determinants in Env, no qualitative differences were revealed between animals infected with either the clonal or the diverse inocula. However, in vitro studies indicated that the reduced replicative capacity of variants B14 and B28 in vivo was associated with altered interactions between the viruses and the viral receptor and co-receptor. The data suggest that viral variants with GL8-like characteristics have an early, replicative advantage and should provide the focus for future vaccine development.

Comparison of reproductive protection against bovine viral diarrhea virus provided by multivalent viral vaccines containing inactivated fractions of bovine viral diarrhea virus 1 and 2.

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Walz, Paul H; Riddell, Kay P; Newcomer, Benjamin W; Neill, John D; Falkenberg, Shollie M; Cortese, Victor S; Scruggs, Daniel W; Short, Thomas H

2018-04-23

Bovine viral diarrhea virus (BVDV) is an important viral cause of reproductive disease, immune suppression and clinical disease in cattle. The objective of this study was to compare reproductive protection in cattle against the impacts of bovine viral diarrhea virus (BVDV) provided by three different multivalent vaccines containing inactivated BVDV. BVDV negative beef heifers and cows (n = 122) were randomly assigned to one of four groups. Groups A-C (n = 34/group) received two pre-breeding doses of one of three commercially available multivalent vaccines containing inactivated fractions of BVDV 1 and BVDV 2, and Group D (n = 20) served as negative control and received two doses of saline prior to breeding. Animals were bred, and following pregnancy diagnosis, 110 cattle [Group A (n = 31); Group B (n = 32); Group C (n = 31); Group D (n = 16)] were subjected to a 28-day exposure to cattle persistently infected (PI) with BVDV (1a, 1b and 2a). Of the 110 pregnancies, 6 pregnancies resulted in fetal resorption with no material for testing. From the resultant 104 pregnancies, BVDV transplacental infections were demonstrated in 73 pregnancies. The BVDV fetal infection rate (FI) was calculated at 13/30 (43%) for Group A cows, 27/29 (93%) for Group B cows, 18/30 (60%) for Group C cows, and 15/15 (100%) for Group D cows. Statistical differences were observed between groups with respect to post-vaccination antibody titers, presence and duration of viremia in pregnant cattle, and fetal infection rates in offspring from BVDV-exposed cows. Group A vaccination resulted in significant protection against BVDV infection as compared to all other groups based upon outcome measurements, while Group B vaccination did not differ in protection against BVDV infection from control Group D. Ability of inactivated BVDV vaccines to provide protection against BVDV fetal infection varies significantly among commercially available products; however, in this challenge

Viral hemagglutinin is involved in promoting the internalisation of Staphylococcus aureus into human pneumocytes during influenza A H1N1 virus infection.

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Passariello, Claudio; Nencioni, Lucia; Sgarbanti, Rossella; Ranieri, Danilo; Torrisi, Maria Rosaria; Ripa, Sandro; Garaci, Enrico; Palamara, Anna Teresa

2011-02-01

Secondary pneumonia caused by Staphylococcus aureus is reemerging as a primary cause of excess mortality associated with infection by the influenza A virus. We have investigated in vitro the cellular and molecular mechanisms underlying this synergism. Experimental data show a significant increase in the efficiency of internalisation of S. aureus into cultured pneumocytes during the early phases of viral infection, while a relevant increase in the efficiency of adhesion is evident only later during viral infection, suggesting that the 2 effects are based on different molecular mechanisms. Data reported in this paper show that S. aureus cells can bind the viral hemagglutinin (HA) and that this binding promotes enhanced bacterial internalisation by 2 mechanisms: binding to HA exposed at the surface of infected cells and binding to free extracellular virions, enabling internalisation at high efficiency also in cells that are not infected by the virus. The affinity of binding that involves S. aureus and HA was shown to be enhanced by the reducing extracellular environment that the virus can generate. Copyright © 2010 Elsevier GmbH. All rights reserved.

Viral marketing: the use of surprise

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Lindgreen, A.; Vanhamme, J.; Clarke, I.; Flaherty, T.B.

2005-01-01

Viral marketing involves consumers passing along a company's marketing message to their friends, family, and colleagues. This chapter reviews viral marketing campaigns and argues that the emotion of surprise often is at work and that this mechanism resembles that of word-of-mouth marketing.

Viral evasion of intracellular DNA and RNA sensing

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Chan, Ying Kai; Gack, Michaela U.

2016-01-01

The co-evolution of viruses with their hosts has led to the emergence of viral pathogens that are adept at evading or actively suppressing host immunity. Pattern recognition receptors (PRRs) are key components of antiviral immunity that detect conserved molecular features of viral pathogens and initiate signalling that results in the expression of antiviral genes. In this Review, we discuss the strategies that viruses use to escape immune surveillance by key intracellular sensors of viral RNA or DNA, with a focus on RIG-I-like receptors (RLRs), cyclic GMP–AMP synthase (cGAS) and interferon-γ (IFNγ)-inducible protein 16 (IFI16). Such viral strategies include the sequestration or modification of viral nucleic acids, interference with specific post-translational modifications of PRRs or their adaptor proteins, the degradation or cleavage of PRRs or their adaptors, and the sequestration or relocalization of PRRs. An understanding of viral immune-evasion mechanisms at the molecular level may guide the development of vaccines and antivirals. PMID:27174148

Viral infection upregulates myostatin promoter activity in orange-spotted grouper (Epinephelus coioides).

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Chen, Yi-Tien; Lin, Chao-Fen; Chen, Young-Mao; Lo, Chih-En; Chen, Wan-Erh; Chen, Tzong-Yueh

2017-01-01

Myostatin is a negative regulator of myogenesis and has been suggested to be an important factor in the development of muscle wasting during viral infection. The objective of this study was to characterize the main regulatory element of the grouper myostatin promoter and to study changes in promoter activity due to viral stimulation. In vitro and in vivo experiments indicated that the E-box E6 is a positive cis-and trans-regulation motif, and an essential binding site for MyoD. In contrast, the E-box E5 is a dominant negative cis-regulatory. The characteristics of grouper myostatin promoter are similar in regulation of muscle growth to that of other species, but mainly through specific regulatory elements. According to these results, we conducted a study to investigate the effect of viral infection on myostatin promoter activity and its regulation. The nervous necrosis virus (NNV) treatment significantly induced myostatin promoter activity. The present study is the first report describing that specific myostatin motifs regulate promoter activity and response to viral infection.

Viral infection upregulates myostatin promoter activity in orange-spotted grouper (Epinephelus coioides.

Directory of Open Access Journals (Sweden)

Yi-Tien Chen

Full Text Available Myostatin is a negative regulator of myogenesis and has been suggested to be an important factor in the development of muscle wasting during viral infection. The objective of this study was to characterize the main regulatory element of the grouper myostatin promoter and to study changes in promoter activity due to viral stimulation. In vitro and in vivo experiments indicated that the E-box E6 is a positive cis-and trans-regulation motif, and an essential binding site for MyoD. In contrast, the E-box E5 is a dominant negative cis-regulatory. The characteristics of grouper myostatin promoter are similar in regulation of muscle growth to that of other species, but mainly through specific regulatory elements. According to these results, we conducted a study to investigate the effect of viral infection on myostatin promoter activity and its regulation. The nervous necrosis virus (NNV treatment significantly induced myostatin promoter activity. The present study is the first report describing that specific myostatin motifs regulate promoter activity and response to viral infection.

Male circumcision significantly reduces prevalence and load of genital anaerobic bacteria.

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Liu, Cindy M; Hungate, Bruce A; Tobian, Aaron A R; Serwadda, David; Ravel, Jacques; Lester, Richard; Kigozi, Godfrey; Aziz, Maliha; Galiwango, Ronald M; Nalugoda, Fred; Contente-Cuomo, Tania L; Wawer, Maria J; Keim, Paul; Gray, Ronald H; Price, Lance B

2013-04-16

Male circumcision reduces female-to-male HIV transmission. Hypothesized mechanisms for this protective effect include decreased HIV target cell recruitment and activation due to changes in the penis microbiome. We compared the coronal sulcus microbiota of men from a group of uncircumcised controls (n = 77) and from a circumcised intervention group (n = 79) at enrollment and year 1 follow-up in a randomized circumcision trial in Rakai, Uganda. We characterized microbiota using16S rRNA gene-based quantitative PCR (qPCR) and pyrosequencing, log response ratio (LRR), Bayesian classification, nonmetric multidimensional scaling (nMDS), and permutational multivariate analysis of variance (PerMANOVA). At baseline, men in both study arms had comparable coronal sulcus microbiota; however, by year 1, circumcision decreased the total bacterial load and reduced microbiota biodiversity. Specifically, the prevalence and absolute abundance of 12 anaerobic bacterial taxa decreased significantly in the circumcised men. While aerobic bacterial taxa also increased postcircumcision, these gains were minor. The reduction in anaerobes may partly account for the effects of circumcision on reduced HIV acquisition. The bacterial changes identified in this study may play an important role in the HIV risk reduction conferred by male circumcision. Decreasing the load of specific anaerobes could reduce HIV target cell recruitment to the foreskin. Understanding the mechanisms that underlie the benefits of male circumcision could help to identify new intervention strategies for decreasing HIV transmission, applicable to populations with high HIV prevalence where male circumcision is culturally less acceptable.

Oxygen tension level and human viral infections

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Morinet, Frédéric, E-mail: frederic.morinet@sls.aphp.fr [Centre des Innovations Thérapeutiques en Oncologie et Hématologie (CITOH), CHU Saint-Louis, Paris (France); Université Denis Diderot, Sorbonne Paris Cité Paris, Paris (France); Casetti, Luana [Institut Cochin INSERM U1016, Paris (France); François, Jean-Hugues; Capron, Claude [Institut Cochin INSERM U1016, Paris (France); Laboratoire d' Hématologie, Hôpital Ambroise Paré, Boulogne (France); Université de Versailles Saint-Quentin en Yvelynes, Versailles (France); Pillet, Sylvie [Laboratoire de Bactériologie-Virologie-Hygiène, CHU de Saint-Etienne, Saint-Etienne (France); Université de Lyon et Université de Saint-Etienne, Jean Monnet, GIMAP EA3064, F-42023 Saint-Etienne, Lyon (France)

2013-09-15

The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition. - Highlights: • Oxygen tension level regulates viral replication in vitro and possibly in vivo. • Hypoxia-inducible factor 1 (HIF-1α) is the principal factor involved in Oxygen tension level. • HIF-1α upregulates gene expression for example of HIV, JC and Kaposi sarcoma viruses. • In addition to classical chemotherapy inhibition of HIF-1α may constitute a new track to treat human viral infections.

Rituximab-related viral infections in lymphoma patients.

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Aksoy, Sercan; Harputluoglu, Hakan; Kilickap, Saadettin; Dede, Didem Sener; Dizdar, Omer; Altundag, Kadri; Barista, Ibrahim

2007-07-01

Recently, a human/mouse chimeric monoclonal antibody, rituximab, has been successfully used to treat cases of B-cell non-Hodgkin's lymphoma and some autoimmune diseases. However, several viral infections related to rituximab have been reported in the literature, but were not well characterized. To further investigate this topic, relevant English language studies were identified through Medline. There were 64 previously reported cases of serious viral infection after rituximab treatment. The median age of the cases was 61 years (range: 21 - 79). The median time period from the start of rituximab treatment to viral infection diagnosis was 5.0 months (range: 1 - 20). The most frequently experienced viral infections were hepatitis B virus (HBV) (39.1%, n = 25), cytomegalovirus infection (CMV) (23.4%, n = 15), varicella-zoster virus (VZV) (9.4%, n = 6), and others (28.1%, n = 18). Of the patients with HBV infections, 13 (52.0%) died due to hepatic failure. Among the 39 cases that had viral infections other than HBV, 13 died due to these specific infections. In this study, about 50% of the rituximab-related HBV infections resulted in death, whereas this was the case in only 33% of the cases with other infections. Close monitoring for viral infection, particularly HBV and CMV, in patients treated with rituximab should be recommended.

Viral vector-based influenza vaccines

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de Vries, Rory D.; Rimmelzwaan, Guus F.

2016-01-01

ABSTRACT Antigenic drift of seasonal influenza viruses and the occasional introduction of influenza viruses of novel subtypes into the human population complicate the timely production of effective vaccines that antigenically match the virus strains that cause epidemic or pandemic outbreaks. The development of game-changing vaccines that induce broadly protective immunity against a wide variety of influenza viruses is an unmet need, in which recombinant viral vectors may provide. Use of viral vectors allows the delivery of any influenza virus antigen, or derivative thereof, to the immune system, resulting in the optimal induction of virus-specific B- and T-cell responses against this antigen of choice. This systematic review discusses results obtained with vectored influenza virus vaccines and advantages and disadvantages of the currently available viral vectors. PMID:27455345

Murine Leukemia Virus Uses TREX Components for Efficient Nuclear Export of Unspliced Viral Transcripts

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Toshie Sakuma

2014-03-01

Full Text Available Previously we reported that nuclear export of both unspliced and spliced murine leukemia virus (MLV transcripts depends on the nuclear export factor (NXF1 pathway. Although the mRNA export complex TREX, which contains Aly/REF, UAP56, and the THO complex, is involved in the NXF1-mediated nuclear export of cellular mRNAs, its contribution to the export of MLV mRNA transcripts remains poorly understood. Here, we studied the involvement of TREX components in the export of MLV transcripts. Depletion of UAP56, but not Aly/REF, reduced the level of both unspliced and spliced viral transcripts in the cytoplasm. Interestingly, depletion of THO components, including THOC5 and THOC7, affected only unspliced viral transcripts in the cytoplasm. Moreover, the RNA immunoprecipitation assay showed that only the unspliced viral transcript interacted with THOC5. These results imply that MLV requires UAP56, THOC5 and THOC7, in addition to NXF1, for nuclear export of viral transcripts. Given that naturally intronless mRNAs, but not bulk mRNAs, require THOC5 for nuclear export, it is plausible that THOC5 plays a key role in the export of unspliced MLV transcripts.

Viral vectors for production of recombinant proteins in plants.

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Lico, Chiara; Chen, Qiang; Santi, Luca

2008-08-01

Global demand for recombinant proteins has steadily accelerated for the last 20 years. These recombinant proteins have a wide range of important applications, including vaccines and therapeutics for human and animal health, industrial enzymes, new materials and components of novel nano-particles for various applications. The majority of recombinant proteins are produced by traditional biological "factories," that is, predominantly mammalian and microbial cell cultures along with yeast and insect cells. However, these traditional technologies cannot satisfy the increasing market demand due to prohibitive capital investment requirements. During the last two decades, plants have been under intensive investigation to provide an alternative system for cost-effective, highly scalable, and safe production of recombinant proteins. Although the genetic engineering of plant viral vectors for heterologous gene expression can be dated back to the early 1980s, recent understanding of plant virology and technical progress in molecular biology have allowed for significant improvements and fine tuning of these vectors. These breakthroughs enable the flourishing of a variety of new viral-based expression systems and their wide application by academic and industry groups. In this review, we describe the principal plant viral-based production strategies and the latest plant viral expression systems, with a particular focus on the variety of proteins produced and their applications. We will summarize the recent progress in the downstream processing of plant materials for efficient extraction and purification of recombinant proteins. (c) 2008 Wiley-Liss, Inc.

CD4 T Cell Responses in Latent and Chronic Viral Infections

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Walton, Senta; Mandaric, Sanja; Oxenius, Annette

2013-01-01

The spectrum of tasks which is fulfilled by CD4 T cells in the setting of viral infections is large, ranging from support of CD8 T cells and humoral immunity to exertion of direct antiviral effector functions. While our knowledge about the differentiation pathways, plasticity, and memory of CD4 T cell responses upon acute infections or immunizations has significantly increased during the past years, much less is still known about CD4 T cell differentiation and their beneficial or pathological functions during persistent viral infections. In this review we summarize current knowledge about the differentiation, direct or indirect antiviral effector functions, and the regulation of virus-specific CD4 T cells in the setting of persistent latent or active chronic viral infections with a particular emphasis on herpes virus infections for the former and chronic lymphocytic choriomeningitis virus infection for the latter. PMID:23717308

Sequence elements correlating with circulating viral load in genotype 1b hepatitis C virus infection

International Nuclear Information System (INIS)

Watanabe, Hideki; Nagayama, Kazuyoshi; Enomoto, Nobuyuki; Itakura, Jun; Tanabe, Yoko; Hamano, Kosei; Izumi, Namiki; Sato, Chifumi; Watanabe, Mamoru

2003-01-01

The correlation between hepatitis C virus (HCV) genomic sequences and circulating HCV RNA levels was assessed to investigate the genetic elements affecting viral load. The interferon sensitivity-determining region (ISDR) sequence and the serum viral load were strongly correlated in 226 patients examined. Analysis of the entire HCV genome from six patients (three with a high and the others with a low viral load) with similar ISDR sequences identified several candidate residues associated with viral load. The amino acid (aa) sequences of these candidate residues and flanking regions in 67 additional patients revealed that only the residue at aa 962 varied significantly between the HCV patients with low and high serum loads (P 0.042). At this position, alanine was observed more frequently in the patients with a high viral load. In conclusion, our results strongly suggest that serum HCV RNA loads are inversely correlated with amino acid substitutions in the ISDR, and aa 962 was identified as a possible second determinant of serum HCV RNA load

De novo assembly of highly diverse viral populations

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Yang Xiao

2012-09-01

Full Text Available Abstract Background Extensive genetic diversity in viral populations within infected hosts and the divergence of variants from existing reference genomes impede the analysis of deep viral sequencing data. A de novo population consensus assembly is valuable both as a single linear representation of the population and as a backbone on which intra-host variants can be accurately mapped. The availability of consensus assemblies and robustly mapped variants are crucial to the genetic study of viral disease progression, transmission dynamics, and viral evolution. Existing de novo assembly techniques fail to robustly assemble ultra-deep sequence data from genetically heterogeneous populations such as viruses into full-length genomes due to the presence of extensive genetic variability, contaminants, and variable sequence coverage. Results We present VICUNA, a de novo assembly algorithm suitable for generating consensus assemblies from genetically heterogeneous populations. We demonstrate its effectiveness on Dengue, Human Immunodeficiency and West Nile viral populations, representing a range of intra-host diversity. Compared to state-of-the-art assemblers designed for haploid or diploid systems, VICUNA recovers full-length consensus and captures insertion/deletion polymorphisms in diverse samples. Final assemblies maintain a high base calling accuracy. VICUNA program is publicly available at: http://www.broadinstitute.org/scientific-community/science/projects/viral-genomics/ viral-genomics-analysis-software. Conclusions We developed VICUNA, a publicly available software tool, that enables consensus assembly of ultra-deep sequence derived from diverse viral populations. While VICUNA was developed for the analysis of viral populations, its application to other heterogeneous sequence data sets such as metagenomic or tumor cell population samples may prove beneficial in these fields of research.

Hemostatic System in Chronic Viral Hepatitis

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Natalia Borisova

2018-06-01

Full Text Available Hemostasis is balanced by pro- and anticoagulant and pro- and antifibrinolytic factors, most of these being synthesized by the liver. Advanced liver disease is associated with perturbations in the level of these factors due to secretory deficiencies. Thrombocytopenia, reduced levels of factor II-VII-X, and anti-fibrinolytic factors are all features of CHC infection, suggesting hypocoagulability. However, higher concentrations of VWF and factor VIII, as well as lower concentrations of anticoagulant factors including protein C and S, have also been reported in CHC infections, suggesting hypercoagulability. Thus, the hemostatic balance in the patient with liver disease is relatively unstable as evidenced by the occurrence of both bleeding and thrombotic complications in a significant proportion of patients with chronic viral hepatitis. In patients with chronic liver disease (CLD, in whom extremely complex alterations of hemostasis occur, one cannot rely on levels of individual coagulation factors, or on simplified tests of hemostasis such as the PT or APTT to predict the hemostatic status. To determine the hemostatic status in these patients, more complex tests and a more comprehensive overview of the hemostatic changes are required. In connection with the latest studies, a revision of the methods for correction of hemostatic system disorders in patients with acute and chronic liver diseases becomes urgent.

[Relationship between viral load of human bocavirus and clinical characteristics in children with acute lower respiratory tract infection].

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Ding, Xiao-Fang; Zhang, Bing; Zhong, Li-Li; Xie, Le-Yun; Xiao, Ni-Guang

2017-03-01

To investigate the prevalence of human bocavirus (HBoV) in children with acute lower respiratory tract infection and to explore the relationship between the viral load of HBoV and the clinical characteristics of acute lower respiratory tract infection in children. A total of 1 554 nasopharyngeal aspirates from children who were hospitalized due to acute lower respiratory tract infection between March 2011 and March 2014 were collected. Quantitative real-time PCR was used to detect 12 RNA and 2 DNA viruses, adenovirus (ADV) and HBoV, and to measure the viral load of HBoV in HBoV-positive children. A comprehensive analysis was performed with reference to clinical symptoms and indicators. In the 1 554 specimens, 1 212 (77.99%) were positive for viruses, and 275 (17.70%) were HBoV-positive. In HBoV-positive cases, 94.9% were aged infection, and 230 (83.64%) had mixed infection. There was no significant difference in viral load between children with single infection and mixed infection (P>0.05). The patients with fever had a significantly higher viral load than those without fever (Pacute lower respiratory tract infection (P>0.05). HBoV is one of the important pathogens of acute lower respiratory tract infection in children. Children with a higher viral load of HBoV are more likely to experience symptoms such as fever and wheezing. However, the severity of disease and mixed infection are not significantly related to viral load.

Raw Sewage Harbors Diverse Viral Populations

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Cantalupo, Paul G.; Calgua, Byron; Zhao, Guoyan; Hundesa, Ayalkibet; Wier, Adam D.; Katz, Josh P.; Grabe, Michael; Hendrix, Roger W.; Girones, Rosina; Wang, David; Pipas, James M.

2011-01-01

ABSTRACT At this time, about 3,000 different viruses are recognized, but metagenomic studies suggest that these viruses are a small fraction of the viruses that exist in nature. We have explored viral diversity by deep sequencing nucleic acids obtained from virion populations enriched from raw sewage. We identified 234 known viruses, including 17 that infect humans. Plant, insect, and algal viruses as well as bacteriophages were also present. These viruses represented 26 taxonomic families and included viruses with single-stranded DNA (ssDNA), double-stranded DNA (dsDNA), positive-sense ssRNA [ssRNA(+)], and dsRNA genomes. Novel viruses that could be placed in specific taxa represented 51 different families, making untreated wastewater the most diverse viral metagenome (genetic material recovered directly from environmental samples) examined thus far. However, the vast majority of sequence reads bore little or no sequence relation to known viruses and thus could not be placed into specific taxa. These results show that the vast majority of the viruses on Earth have not yet been characterized. Untreated wastewater provides a rich matrix for identifying novel viruses and for studying virus diversity. Importance At this time, virology is focused on the study of a relatively small number of viral species. Specific viruses are studied either because they are easily propagated in the laboratory or because they are associated with disease. The lack of knowledge of the size and characteristics of the viral universe and the diversity of viral genomes is a roadblock to understanding important issues, such as the origin of emerging pathogens and the extent of gene exchange among viruses. Untreated wastewater is an ideal system for assessing viral diversity because virion populations from large numbers of individuals are deposited and because raw sewage itself provides a rich environment for the growth of diverse host species and thus their viruses. These studies suggest that

Detection of serum leptin levels in patients with viral hepatitis C

International Nuclear Information System (INIS)

Sun Shuhong; Yu Hua; Niu Airong; Wu Yuqing

2006-01-01

To evaluate changes of serum leptin levels in patients with viral hepatitis C(HCV), serum leptin levels were determined by RIA in 65 patients with viral chronic hepatitis C and in 80 control subjects ,liver function (ALT, AST) , glucose (Glu) , and total cholesterol (TC) were evaluated too. Campared with controls, the levels of serum leptin were significantly increased in patients with HCV (P 0.05). The levels of serum leptin increased in patients with HCV, which correlates positively with the severity of liver inflammation, so that leptin can be regarded as an index which reflects the severity of liver inflammation. (authors)

Persistent viral infections and immune aging.

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Brunner, Stefan; Herndler-Brandstetter, Dietmar; Weinberger, Birgit; Grubeck-Loebenstein, Beatrix

2011-07-01

Immunosenescence comprises a set of dynamic changes occurring to both, the innate as well as the adaptive immune system that accompany human aging and result in complex manifestations of still poorly defined deficiencies in the elderly population. One of the most prominent alterations during aging is the continuous involution of the thymus gland which is almost complete by the age of 50. Consequently, the output of naïve T cells is greatly diminished in elderly individuals which puts pressure on homeostatic forces to maintain a steady T cell pool for most of adulthood. In a great proportion of the human population, this fragile balance is challenged by persistent viral infections, especially Cytomegalovirus (CMV), that oblige certain T cell clones to monoclonally expand repeatedly over a lifetime which then occupy space within the T cell pool. Eventually, these inflated memory T cell clones become exhausted and their extensive accumulation accelerates the age-dependent decline of the diversity of the T cell pool. As a consequence, infectious diseases are more frequent and severe in elderly persons and immunological protection following vaccination is reduced. This review therefore aims to shed light on how various types of persistent viral infections, especially CMV, influence the aging of the immune system and highlight potential measures to prevent the age-related decline in immune function. Copyright © 2010 Elsevier B.V. All rights reserved.

Viral gametocytic hypertrophy of Crassostrea gigas in France: from occasional records to disease emergence?

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Garcia, Céline; Robert, Maeva; Arzul, Isabelle; Chollet, Bruno; Joly, Jean-Pierre; Miossec, Laurence; Comtet, Thierry; Berthe, Franck

2006-06-23

Viral gametocytic hypertrophy was reported for the first time in 2001 in Pacific oyster Crassostrea gigas in France. Since this date, the number of reported cases and the distribution area have increased every year; however, the cases are not associated with macroscopic signs or increased mortality rates. Both male and female gametes were hypertrophied and basophilic inclusions were observed in gamete nuclei. Transmission electron microscopy revealed the presence of viral particles in these intranuclear basophilic inclusions. These particles had characteristics similar to those of the Papillomaviridae and Polyoma viridae families: they were small, non-enveloped, icosahedral, and 44 to 56 nm in diameter. The viral particles were found in male, female and hermaphrodite oysters and no significant difference in viral infection was observed between those groups. The frequency of detection and the intensity of infection were low and no host defence reaction was recognised, suggesting that the viral particles had a weak impact on C. gigas. The viral particles described in the present study seem to be similar to these described in C. virginica in the USA and Canada and in C. gigas in Korea, but further studies are required to confirm their identity. The issue of a possible emergence of this infection is discussed.

Wastewater viral community

Data.gov (United States)

U.S. Environmental Protection Agency — The dataset contains the information used to generate the figures in the manuscript. The data describes the viral loss measured at all steps of sample processing,...

Viral DNA Sensors IFI16 and Cyclic GMP-AMP Synthase Possess Distinct Functions in Regulating Viral Gene Expression, Immune Defenses, and Apoptotic Responses during Herpesvirus Infection

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Benjamin A. Diner

2016-11-01

Full Text Available The human interferon-inducible protein IFI16 is an important antiviral factor that binds nuclear viral DNA and promotes antiviral responses. Here, we define IFI16 dynamics in space and time and its distinct functions from the DNA sensor cyclic dinucleotide GMP-AMP synthase (cGAS. Live-cell imaging reveals a multiphasic IFI16 redistribution, first to viral entry sites at the nuclear periphery and then to nucleoplasmic puncta upon herpes simplex virus 1 (HSV-1 and human cytomegalovirus (HCMV infections. Optogenetics and live-cell microscopy establish the IFI16 pyrin domain as required for nuclear periphery localization and oligomerization. Furthermore, using proteomics, we define the signature protein interactions of the IFI16 pyrin and HIN200 domains and demonstrate the necessity of pyrin for IFI16 interactions with antiviral proteins PML and cGAS. We probe signaling pathways engaged by IFI16, cGAS, and PML using clustered regularly interspaced short palindromic repeat (CRISPR/Cas9-mediated knockouts in primary fibroblasts. While IFI16 induces cytokines, only cGAS activates STING/TBK-1/IRF3 and apoptotic responses upon HSV-1 and HCMV infections. cGAS-dependent apoptosis upon DNA stimulation requires both the enzymatic production of cyclic dinucleotides and STING. We show that IFI16, not cGAS or PML, represses HSV-1 gene expression, reducing virus titers. This indicates that regulation of viral gene expression may function as a greater barrier to viral replication than the induction of antiviral cytokines. Altogether, our findings establish coordinated and distinct antiviral functions for IFI16 and cGAS against herpesviruses.

Viral etiology of bronchiolitis among pediatric inpatients in northern Taiwan with emphasis on newly identified respiratory viruses.

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Chen, Yu-Wen; Huang, Yhu-Chering; Ho, Tai-Hua; Huang, Chung-Guei; Tsao, Kuo-Chien; Lin, Tzou-Yien

2014-04-01

Viral etiology of bronchiolitis in children in Taiwan has been fragmentary. We conducted a prospective study to figure out the viral epidemiology of bronchiolitis in Taiwan. From January 2009 to March 2011, a total of 113 children with bronchiolitis, aged culture, antigen test, and polymerase chain reaction. A total of 120 viruses were detected from 113 children. Positive viral etiology was identified in 86 (76%) children. Mixed viral pathogens were found in 28 cases (25%). Respiratory syncytial virus (RSV) was the most common pathogen and was identified in 43.4% of the cases. Human bocavirus (hBoV) was the second most common identified virus (in 19.5%), followed by human metapneumovirus (hMPV), rhinovirus, influenza viruses, and coronavirus OC43. In terms of clinical characteristics, no significant difference was found among the children with bronchiolitis either caused by different single or mixed viral infection. RSV was the most common etiologic agent for children with bronchiolitis in Taiwan. Newly identified viruses, including hMPV and hBoV, were also among the common causative agents. Clinical characteristics were not significantly different among the children with bronchiolitis caused by different viruses. Copyright © 2012. Published by Elsevier B.V.

Recycling Endosomes and Viral Infection.

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Vale-Costa, Sílvia; Amorim, Maria João

2016-03-08

Many viruses exploit specific arms of the endomembrane system. The unique composition of each arm prompts the development of remarkably specific interactions between viruses and sub-organelles. This review focuses on the viral-host interactions occurring on the endocytic recycling compartment (ERC), and mediated by its regulatory Ras-related in brain (Rab) GTPase Rab11. This protein regulates trafficking from the ERC and the trans-Golgi network to the plasma membrane. Such transport comprises intricate networks of proteins/lipids operating sequentially from the membrane of origin up to the cell surface. Rab11 is also emerging as a critical factor in an increasing number of infections by major animal viruses, including pathogens that provoke human disease. Understanding the interplay between the ERC and viruses is a milestone in human health. Rab11 has been associated with several steps of the viral lifecycles by unclear processes that use sophisticated diversified host machinery. For this reason, we first explore the state-of-the-art on processes regulating membrane composition and trafficking. Subsequently, this review outlines viral interactions with the ERC, highlighting current knowledge on viral-host binding partners. Finally, using examples from the few mechanistic studies available we emphasize how ERC functions are adjusted during infection to remodel cytoskeleton dynamics, innate immunity and membrane composition.

Current status and strategies for the control of viral hepatitis A in Korea.

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Yoon, Eileen L; Sinn, Dong Hyun; Lee, Hyun Woong; Kim, Ji Hoon

2017-09-01

Hepatitis A virus is one of the most frequent causes of foodborne infection, which is closely associated with sanitary conditions and hygienic practices. The clinical spectrum of acute hepatitis A is wide, ranging from mild case without any noticeable symptoms to severe case with acute liver failure leading to mortality. The severity and outcome are highly correlated with age at infection. In developing countries, most people are infected in early childhood without significant symptom. Ironically, in area where sanitary condition has improved rapidly, adults who do not have immunity for viral hepatitis A (VH-A) in early childhood is accumulating. Adults without immunity are exposed to risks of symptomatic disease and large outbreaks in society. In Korea, where hygiene has improved rapidly, acute hepatitis A is a significant health burden that needs to be managed with nationwide health policy. The incidence of symptomatic VH-A has increased since 2000 and peaked in 2009. Korea has designated hepatitis A as a group 1 nationally notifiable infectious disease in 2001. Since 2001, mandatory surveillance system has been established to detect every single case of acute hepatitis A. Universal, nationwide vaccination program for newborns was introduced in 2015. In this review, we will present the current epidemiologic status of viral hepatitis A, and evaluate the effectiveness of the current nationwide strategies for the control of viral hepatitis A in Korea. Furthermore, we presented some action proposals that can help eliminate viral hepatitis A, which is a significant health burden in Korea.

Improved detection of Bovine Viral Diarrhea Virus in Bovine lymphoid cell lines using PrimeFlow RNA assay

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Bovine viral diarrhea virus (BVDV) infections, whether as acute, persistent or contributing to co-infections, result in significant losses for cattle producers. BVDV can be identified by real-time PCR and ELISA, detection and quantification of viral infection at the single cell level is extremely di...

CSF lactate level: a useful diagnostic tool to differentiate acute bacterial and viral meningitis.

Science.gov (United States)

Abro, Ali Hassan; Abdou, Ahmed Saheh; Ustadi, Abdulla M; Saleh, Ahmed Alhaj; Younis, Nadeem Javeed; Doleh, Wafa F

2009-08-01

To evaluate the potential role of CSF lactate level in the diagnosis of acute bacterial meningitis and in the differentiation between viral and bacterial meningitis. This was a hospital based observational study, conducted at Infectious Diseases Unit, Rashid Hospital Dubai, United Arab Emirates, from July 2004 to June 2007. The patients with clinical diagnosis of acute bacterial meningitis and who had CSF Gram stain/culture positive, CSF analysis suggestive of bacterial meningitis with negative Gram stain and culture but blood culture positive for bacteria and patients with clinical diagnosis suggestive of viral meningitis supported by CSF chemical analysis with negative Gram stain and culture as well as negative blood culture for bacteria were included in the study. CT scan brain was done for all patients before lumber puncture and CSF and blood samples were collected immediately after admission. CSF chemical analysis including lactate level was done on first spinal tap. The CSF lactate level was tested by Enzymatic Colorimetric method. A total 95 adult patients of acute meningitis (53 bacterial and 42 viral) fulfilled the inclusion criteria. Among 53 bacterial meningitis patients, Neisseria meningitides were isolated in 29 (54.7%), Strept. Pneumoniae in 18 (33.96%), Staph. Aureus in 2 (3.77%), Klebsiell Pneumoniae in 2 (3.77%), Strept. Agalactiae in 1 (1.8%) and E. Coli in 1 (1.8%). All the patients with bacterial meningitis had CSF lactate > 3.8 mmol/l except one, whereas none of the patients with viral meningitis had lactate level > 3.8 mmol/l. The mean CSF lactate level in bacterial meningitis cases amounted to 16.51 +/- 6.14 mmol/l, whereas it was significantly lower in viral group 2.36 +/- 0.6 mmol/l, p < .0001. CSF lactate level was significantly high in bacterial than viral meningitis and it can provide pertinent, rapid and reliable diagnostic information. Furthermore, CSF lactate level can also differentiate bacterial meningitis from viral one in a quick

Differences in viral load among human respiratory syncytial virus genotypes in hospitalized children with severe acute respiratory infections in the Philippines.

Science.gov (United States)

Kadji, Francois Marie Ngako; Okamoto, Michiko; Furuse, Yuki; Tamaki, Raita; Suzuki, Akira; Lirio, Irene; Dapat, Clyde; Malasao, Rungnapa; Saito, Mariko; Pedrera-Rico, Gay Anne Granada; Tallo, Veronica; Lupisan, Socorro; Saito, Mayuko; Oshitani, Hitoshi

2016-06-27

Human respiratory syncytial virus (HRSV) is a leading viral etiologic agent of pediatric lower respiratory infections, including bronchiolitis and pneumonia. Two antigenic subgroups, HRSV-A and B, each contain several genotypes. While viral load may vary among HRSV genotypes and affect the clinical course of disease, data are scarce regarding the actual differences among genotypes. Therefore, this study estimated and compared viral load among NA1 and ON1 genotypes of HRSV-A and BA9 of HRSV-B. ON1 is a newly emerged genotype with a 72-nucleotide duplication in the G gene as observed previously with BA genotypes in HRSV-B. Children <5 years of age with an initial diagnosis of severe or very severe pneumonia at a hospital in the Philippines from September 2012 to December 2013 were enrolled. HRSV genotypes were determined and the viral load measured from nasopharyngeal swabs (NPS). The viral load of HRSV genotype NA1 were significantly higher than those of ON1 and BA9. Regression analysis showed that both genotype NA1 and younger age were significantly associated with high HRSV viral load. The viral load of NA1 was higher than that of ON1 and BA9 in NPS samples. HRSV genotypes may be associated with HRSV viral load. The reasons and clinical impacts of these differences in viral load among HRSV genotypes require further evaluation.

Microbiological diagnostics of viral hepatitis

OpenAIRE

HASDEMİR, Ufuk

2016-01-01

Viral hepatitis is an infection that primarily affects the liverbut may also have systemic clinical manifestations. The vastmajority of viral hepatitis are caused by one of five hepatotropicviruses: hepatitis A virus (HAV), hepatitis B virus (HBV),hepatitis C virus (HCV), hepatitis D (delta) virus (HDV), andhepatitis E virus (HEV) (Table I) [1]. HBV, HCV, and HDValso cause chronic hepatitis, whereas HAV does not. HEVcauses acute hepatitis in normal hosts but can cause protractedand chronic he...

Valuable Virality

NARCIS (Netherlands)

Akpinar, E.; Berger, Jonah

2017-01-01

Given recent interest in social media, many brands now create content that they hope consumers will view and share with peers. While some campaigns indeed go “viral,” their value to the brand is limited if they do not boost brand evaluation or increase purchase. Consequently, a key question is how

Quilting after mastectomy significantly reduces seroma formation

African Journals Online (AJOL)

reduce or prevent seroma formation among mastectomy patients ... of this prospective study is to evaluate the effect of surgical quilting ... Seroma was more common in smokers (p=0.003) and was not decreased by the .... explain its aetiology.

Autophagy pathway induced by a plant virus facilitates viral spread and transmission by its insect vector.

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Yong Chen

2017-11-01

Full Text Available Many viral pathogens are persistently transmitted by insect vectors and cause agricultural or health problems. Generally, an insect vector can use autophagy as an intrinsic antiviral defense mechanism against viral infection. Whether viruses can evolve to exploit autophagy to promote their transmission by insect vectors is still unknown. Here, we show that the autophagic process is triggered by the persistent replication of a plant reovirus, rice gall dwarf virus (RGDV in cultured leafhopper vector cells and in intact insects, as demonstrated by the appearance of obvious virus-containing double-membrane autophagosomes, conversion of ATG8-I to ATG8-II and increased level of autophagic flux. Such virus-containing autophagosomes seem able to mediate nonlytic viral release from cultured cells or facilitate viral spread in the leafhopper intestine. Applying the autophagy inhibitor 3-methyladenine or silencing the expression of Atg5 significantly decrease viral spread in vitro and in vivo, whereas applying the autophagy inducer rapamycin or silencing the expression of Torc1 facilitate such viral spread. Furthermore, we find that activation of autophagy facilitates efficient viral transmission, whereas inhibiting autophagy blocks viral transmission by its insect vector. Together, these results indicate a plant virus can induce the formation of autophagosomes for carrying virions, thus facilitating viral spread and transmission by its insect vector. We believe that such a role for virus-induced autophagy is common for vector-borne persistent viruses during their transmission by insect vectors.

Clinical characteristics and viral load of respiratory syncytial virus and human metapneumovirus in children hospitaled for acute lower respiratory tract infection.

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Yan, Xiao-Li; Li, Yu-Ning; Tang, Yi-Jie; Xie, Zhi-Ping; Gao, Han-Chun; Yang, Xue-Mei; Li, Yu-Mei; Liu, Li-Jun; Duan, Zhao-Jun

2017-04-01

Respiratory syncytial virus (RSV) and human metapneumovirus (HMPV) are two common viral pathogens in acute lower respiratory tract infections (ALRTI). However, the association of viral load with clinical characteristics is not well-defined in ALRTI. To explore the correlation between viral load and clinical characteristics of RSV and HMPV in children hospitalized for ALRTI in Lanzhou, China. Three hundred and eighty-seven children hospitalized for ALRTI were enrolled. Nasopharyngeal aspirates (NPAs) were sampled from each children. Real-time PCR was used to screen RSV, HMPV, and twelve additional respiratory viruses. Bronchiolitis was the leading diagnoses both in RSV and HMPV positive patients. A significantly greater frequency of wheezing (52% vs. 33.52%, P = 0.000) was noted in RSV positive and negative patients. The RSV viral load was significant higher in children aged infections (P = 0.000). No difference was found in the clinical features of HMPV positive and negative patients. The HMPV viral load had no correlation with any clinical characteristics. The incidences of severe disease were similar between single infection and coinfection for the two viruses (RSV, P = 0.221; HMPV, P = 0.764) and there has no statistical significance between severity and viral load (P = 0.166 and P = 0.721). Bronchiolitis is the most common disease caused by RSV and HMPV. High viral load or co-infection may be associated with some symptoms but neither has a significant impact on disease severity for the two viruses. J. Med. Virol. 89:589-597, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

PIWIs Go Viral: Arbovirus-Derived piRNAs in Vector Mosquitoes.

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Pascal Miesen

2016-12-01

Full Text Available Vector mosquitoes are responsible for transmission of the majority of arthropod-borne (arbo- viruses. Virus replication in these vectors needs to be sufficiently high to permit efficient virus transfer to vertebrate hosts. The mosquito immune response therefore is a key determinant for arbovirus transmission. Mosquito antiviral immunity is primarily mediated by the small interfering RNA pathway. Besides this well-established antiviral machinery, the PIWI-interacting RNA (piRNA pathway processes viral RNA into piRNAs. In recent years, significant progress has been made in characterizing the biogenesis and function of these viral piRNAs. In this review, we discuss these developments, identify knowledge gaps, and suggest directions for future research.

Geochemical Interactions and Viral-Prokaryote Relationships in Freshwater Environments

Science.gov (United States)

Kyle, J. E.; Ferris, G.

2009-05-01

contributor to prokaryotic abundance but given the elements strong multicollinearity with sulfate, iron was removed from the model (as sulfate acts more conservatively across the range of pH sampled, 2.5-9.0). Geochemical variables that have been reported to influence viral abundances under laboratory and field experiments (i.e. Ca2+, DOC, temperature) had minimal effect in the natural environment despite 2 to 3 orders of magnitude range in the data. However, log transformed viral abundance did revealed a significant relationship with pH (Pearson correlation coefficient of r = 0.70) when using principle component analysis. Prokaryotic abundance did not reveal significant correlations with geochemical parameters (all r < 0.38).

Rabies Virus Infection Induces the Formation of Stress Granules Closely Connected to the Viral Factories.

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Jovan Nikolic

2016-10-01

Full Text Available Stress granules (SGs are membrane-less dynamic structures consisting of mRNA and protein aggregates that form rapidly in response to a wide range of environmental cellular stresses and viral infections. They act as storage sites for translationally silenced mRNAs under stress conditions. During viral infection, SG formation results in the modulation of innate antiviral immune responses, and several viruses have the ability to either promote or prevent SG assembly. Here, we show that rabies virus (RABV induces SG formation in infected cells, as revealed by the detection of SG-marker proteins Ras GTPase-activating protein-binding protein 1 (G3BP1, T-cell intracellular antigen 1 (TIA-1 and poly(A-binding protein (PABP in the RNA granules formed during viral infection. As shown by live cell imaging, RABV-induced SGs are highly dynamic structures that increase in number, grow in size by fusion events, and undergo assembly/disassembly cycles. Some SGs localize in close proximity to cytoplasmic viral factories, known as Negri bodies (NBs. Three dimensional reconstructions reveal that both structures remain distinct even when they are in close contact. In addition, viral mRNAs synthesized in NBs accumulate in the SGs during viral infection, revealing material exchange between both compartments. Although RABV-induced SG formation is not affected in MEFs lacking TIA-1, TIA-1 depletion promotes viral translation which results in an increase of viral replication indicating that TIA-1 has an antiviral effect. Inhibition of PKR expression significantly prevents RABV-SG formation and favors viral replication by increasing viral translation. This is correlated with a drastic inhibition of IFN-B gene expression indicating that SGs likely mediate an antiviral response which is however not sufficient to fully counteract RABV infection.

Elite suppressor-derived HIV-1 envelope glycoproteins exhibit reduced entry efficiency and kinetics.

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Kara G Lassen

2009-04-01

Full Text Available Elite suppressors (ES are a rare subset of HIV-1-infected individuals who are able to maintain HIV-1 viral loads below the limit of detection by ultra-sensitive clinical assays in the absence of antiretroviral therapy. Mechanism(s responsible for this elite control are poorly understood but likely involve both host and viral factors. This study assesses ES plasma-derived envelope glycoprotein (env fitness as a function of entry efficiency as a possible contributor to viral suppression. Fitness of virus entry was first evaluated using a novel inducible cell line with controlled surface expression levels of CD4 (receptor and CCR5 (co-receptor. In the context of physiologic CCR5 and CD4 surface densities, ES envs exhibited significantly decreased entry efficiency relative to chronically infected viremic progressors. ES envs also demonstrated slow entry kinetics indicating the presence of virus with reduced entry fitness. Overall, ES env clones were less efficient at mediating entry than chronic progressor envs. Interestingly, acute infection envs exhibited an intermediate phenotypic pattern not distinctly different from ES or chronic progressor envs. These results imply that lower env fitness may be established early and may directly contribute to viral suppression in ES individuals.

Viral erythrocytic necrosis: Chapter 2.2.7

Science.gov (United States)

Winton, James R.; Hershberger, Paul K.

2014-01-01

Viral erythrocytic necrosis (VEN), originally termed piscine erythrocytic necrosis, is a condition that has been reported to affect the red blood cells (RBCs) of many species of marine and anadromous fishes in both the Atlantic and Pacific Oceans (Nicholson and Reno 1981; Smail 1982; Wolf 1988; Dannevig and Thorud 1999). Fish with VEN may develop a severe anemia that can reduce their stamina, predispose them to other infections or increase the impact of other stressors (MacMillan et al. 1980; Nicholson and Reno 1981; Meyers et al. 1986; Haney et al. 1992) resulting in population-scale impacts in susceptible species (Hershberger et al. 2009).

End-of-Treatment-Response in Patients Treated for Hepatitis C Virus with Standard Interferon and Ribavirin Based on Viral Load

International Nuclear Information System (INIS)

Rathore, M. A.; Hussain, A. B.; Ghani, E.

2015-01-01

Objective: To determine the End-of-Treatment-Response (ETR) to standard interferon and ribavirin based regimen in patients of chronic hepatitis C and to compare the ETR response in low and high viral load groups. Study Design: Descriptive study. Place and Duration of Study: Virology Department, Armed Forces Institute of Pathology (AFIP), Rawalpindi, from March 2012 to May 2013. Methodology: Patients with chronic hepatitis C virus infection were included in the study. Pre-treatment viral load was determined by RoboGene Quantification kit. Based on viral load, the 400 patients were divided into two equal groups of low viral load (< 800,000 IU/ml) and high viral load (> 800,000 IU/ml). The patients were treated with standard interferon alpha (3 million units subcutaneously thrice weekly) and ribavirin (10.6 mg/kg body weight) for 6 months. ETR was measured using Sacace Biotechnologies Qualitative kit. Chi-square test was used to compare the ETR in the two viral load groups. P-value < 0.05 was considered as significant. Results: Out of 400 patients, 206 (51.5%) were males and 194 (48.5%) were females. Two hundred seventy (67.5%) patients achieved ETR and 130 (35.5%) failed to do so. In low viral load group, 145 (72.5%) patients achieved and 55 (27.5%) patients did not achieve ETR. In high viral load group, 123 (61.5%) patients achieved and 77 (38.5%) did not achieve ETR. The difference in ETR between low and high viral load groups was statistically significant (p=0.019). Conclusion: End-of-treatment-response in patients treated for hepatitis C virus with standard interferon and ribavirin was greater in patients with low viral load as compared to patients with high viral load. (author)

Environmental survey to assess viral contamination of air and surfaces in hospital settings.

Science.gov (United States)

Carducci, A; Verani, M; Lombardi, R; Casini, B; Privitera, G

2011-03-01

The presence of pathogenic viruses in healthcare settings represents a serious risk for both staff and patients. Direct viral detection in the environment poses significant technical problems and the indirect indicators currently in use suffer from serious limitations. The aim of this study was to monitor surfaces and air in hospital settings to reveal the presence of hepatitis C virus, human adenovirus, norovirus, human rotavirus and torque teno virus by nucleic acid assays, in parallel with measurements of total bacterial count and haemoglobin presence. In total, 114 surface and 62 air samples were collected. Bacterial contamination was very low (air was 282 cfu/m(3). Overall, 19 (16.7%) surface samples tested positive for viral nucleic acids: one for norovirus, one for human adenovirus and 17 (14.9%) for torque teno virus (TTV). Only this latter virus was directly detected in 10 air samples (16.1%). Haemoglobin was found on two surfaces. No relationship was found between viral, biochemical or bacterial indicators. The data obtained confirm the difficulty of assessing viral contamination using bacterial indicators. The frequent detection of TTV suggests its possible use as an indicator for general viral contamination of the environment. Copyright © 2010 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.

Mast cells in viral infections

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Piotr Witczak

2012-04-01

Full Text Available  There are some premises suggesting that mast cells are involved in the mechanisms of anti-virus defense and in viral disease pathomechanisms. Mast cells are particularly numerous at the portals of infections and thus may have immediate and easy contact with the external environment and invading pathogens. These cells express receptors responsible for recognition of virus-derived PAMP molecules, mainly Toll-like receptors (TLR3, TLR7/8 and TLR9, but also RIG-I-like and NOD-like molecules. Furthermore, mast cells generate various mediators, cytokines and chemokines which modulate the intensity of inflammation and regulate the course of innate and adaptive anti-viral immunity. Indirect evidence for the role of mast cells in viral infections is also provided by clinical observations and results of animal studies. Currently, more and more data indicate that mast cells can be infected by some viruses (dengue virus, adenoviruses, hantaviruses, cytomegaloviruses, reoviruses, HIV-1 virus. It is also demonstrated that mast cells can release pre formed mediators as well as synthesize de novo eicosanoids in response to stimulation by viruses. Several data indicate that virus-stimulated mast cells secrete cytokines and chemokines, including interferons as well as chemokines with a key role in NK and Tc lymphocyte influx. Moreover, some information indicates that mast cell stimulation via TLR3, TLR7/8 and TLR9 can affect their adhesion to extracellular matrix proteins and chemotaxis, and influence expression of some membrane molecules. Critical analysis of current data leads to the conclusion that it is not yet possible to make definitive statements about the role of mast cells in innate and acquired defense mechanisms developing in the course of viral infection and/or pathomechanisms of viral diseases.

Hospital-based surveillance for viral hemorrhagic fevers and hepatitides in Ghana.

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Joseph Humphrey Kofi Bonney

Full Text Available BACKGROUND: Viral hemorrhagic fevers (VHF are acute diseases associated with bleeding, organ failure, and shock. VHF may hardly be distinguished clinically from other diseases in the African hospital, including viral hepatitis. This study was conducted to determine if VHF and viral hepatitis contribute to hospital morbidity in the Central and Northern parts of Ghana. METHODOLOGY/PRINCIPAL FINDINGS: From 2009 to 2011, blood samples of 258 patients with VHF symptoms were collected at 18 hospitals in Ashanti, Brong-Ahafo, Northern, Upper West, and Upper East regions. Patients were tested by PCR for Lassa, Rift Valley, Crimean-Congo, Ebola/Marburg, and yellow fever viruses; hepatitis A (HAV, B (HBV, C (HCV, and E (HEV viruses; and by ELISA for serological hepatitis markers. None of the patients tested positive for VHF. However, 21 (8.1% showed anti-HBc IgM plus HBV DNA and/or HBsAg; 37 (14% showed HBsAg and HBV DNA without anti-HBc IgM; 26 (10% showed anti-HAV IgM and/or HAV RNA; and 20 (7.8% were HCV RNA-positive. None was positive for HEV RNA or anti-HEV IgM plus IgG. Viral genotypes were determined as HAV-IB, HBV-A and E, and HCV-1, 2, and 4. CONCLUSIONS/SIGNIFICANCE: VHFs do not cause significant hospital morbidity in the study area. However, the incidence of acute hepatitis A and B, and hepatitis B and C with active virus replication is high. These infections may mimic VHF and need to be considered if VHF is suspected. The data may help decision makers to allocate resources and focus surveillance systems on the diseases of relevance in Ghana.

Surveillance for Viral Hepatitis - United States, 2014

Science.gov (United States)

... Resource Center Anonymous Feedback Viral Hepatitis Surveillance for Viral Hepatitis – United States, 2014 Recommend on Facebook Tweet Share ... Cases Hepatitis A Hepatitis B Hepatitis C Discussion Hepatitis A virus Index PAGE DESCRIPTION Table 2.1 Reported ...

A patented strain of Bacillus coagulans increased immune response to viral challenge.

Science.gov (United States)

Baron, Mira

2009-03-01

Viral respiratory tract infection is the most common illness among humans. Probiotics have been known to enhance the immune system and, therefore, may represent a significant therapeutic advancement for treating viral respiratory tract infections. A controlled study was conducted to evaluate the effects of the patented GanedenBC30 probiotic (Bacillus coagulans GBI-30, 6086, marketed as Sustenex [Ganeden Biotech, Inc., Mayfield Heights, OH]) on the immune system when exposed to adenovirus and influenza in otherwise healthy adults. Ten healthy men and women (average age, 44 years) were instructed to consume 1 capsule of GanedenBC30 with water once a day for 30 days. At baseline and after completion of the 30-day treatment, blood levels of cytokines were measured in vitro after T-cell exposure to adenovirus and influenza A. Each participant served as his/her own control with baseline blood draw. The use of GanedenBC30 significantly increased T-cell production of TNF-alpha in response to adenovirus exposure (P = 0.027) and influenza A (H3N2 Texas strain) exposure (P = 0.004), but it did not have a significant effect on the response to other strains of influenza. No serious adverse events were reported throughout the study. The patented GanedenBC30 probiotic may be a safe and effective therapeutic option for enhancing T-cell response to certain viral respiratory tract infections.

Tyrosine phosphorylation of AAV2 vectors and its consequences on viral intracellular trafficking and transgene expression

Science.gov (United States)

Zhong, Li; Li, Baozheng; Jayandharan, Giridhararao; Mah, Cathryn S.; Govindasamy, Lakshmanan; Agbandje-McKenna, Mavis; Herzog, Roland W.; Weigel-Van Aken, Kirsten A.; Hobbs, Jacqueline A.; Zolotukhin, Sergei; Muzyczka, Nicholas; Srivastava, Arun

2008-01-01

We have documented that epidermal growth factor receptor protein tyrosine kinase (EGFR-PTK) signaling negatively affects intracellular trafficking and transduction efficiency of recombinant adeno-associated virus 2 (AAV2) vectors. Specifically, inhibition of EGFR-PTK signaling leads to decreased ubiquitination of AAV2 capsid proteins, which in turn, facilitates viral nuclear transport by limiting proteasome-mediated degradation of AAV2 vectors. In the present studies, we observed that AAV capsids can indeed be phosphorylated at tyrosine residues by EGFR-PTK in in vitro phosphorylation assays and that phosphorylated AAV capsids retain their structural integrity. However, although phosphorylated AAV vectors enter cells as efficiently as their unphosphorylated counterparts, their transduction efficiency is significantly reduced. This reduction is not due to impaired viral second-strand DNA synthesis since transduction efficiency of both single-stranded AAV (ssAAV) and self-complementary AAV (scAAV) vectors is decreased by ~68% and ~74%, respectively. We also observed that intracellular trafficking of tyrosine-phosphorylated AAV vectors from cytoplasm to nucleus is significantly decreased, which leads to ubiquitination of AAV capsids followed by proteasome-mediated degradation, although downstream consequences of capsid ubiquitination may also be affected by tyrosine-phosphorylation. These studies provide new insights into the role of tyrosine-phosphorylation of AAV capsids in various steps in the virus life cycle, which has implications in the optimal use of recombinant AAV vectors in human gene therapy. PMID:18834608

Tyrosine-phosphorylation of AAV2 vectors and its consequences on viral intracellular trafficking and transgene expression

International Nuclear Information System (INIS)

Zhong Li; Li Baozheng; Jayandharan, Giridhararao; Mah, Cathryn S.; Govindasamy, Lakshmanan; Agbandje-McKenna, Mavis; Herzog, Roland W.

2008-01-01

We have documented that epidermal growth factor receptor protein tyrosine kinase (EGFR-PTK) signaling negatively affects intracellular trafficking and transduction efficiency of recombinant adeno-associated virus 2 (AAV2) vectors. Specifically, inhibition of EGFR-PTK signaling leads to decreased ubiquitination of AAV2 capsid proteins, which in turn, facilitates viral nuclear transport by limiting proteasome-mediated degradation of AAV2 vectors. In the present studies, we observed that AAV capsids can indeed be phosphorylated at tyrosine residues by EGFR-PTK in in vitro phosphorylation assays and that phosphorylated AAV capsids retain their structural integrity. However, although phosphorylated AAV vectors enter cells as efficiently as their unphosphorylated counterparts, their transduction efficiency is significantly reduced. This reduction is not due to impaired viral second-strand DNA synthesis since transduction efficiency of both single-stranded AAV (ssAAV) and self-complementary AAV (scAAV) vectors is decreased by ∼ 68% and ∼ 74%, respectively. We also observed that intracellular trafficking of tyrosine-phosphorylated AAV vectors from cytoplasm to nucleus is significantly decreased, which results from ubiquitination of AAV capsids followed by proteasome-mediated degradation, although downstream consequences of capsid ubiquitination may also be affected by tyrosine-phosphorylation. These studies provide new insights into the role of tyrosine-phosphorylation of AAV capsids in various steps in the virus life cycle, which has implications in the optimal use of recombinant AAV vectors in human gene therapy

Viral vaccines and their manufacturing cell substrates: New trends and designs in modern vaccinology.

Science.gov (United States)

Rodrigues, Ana F; Soares, Hugo R; Guerreiro, Miguel R; Alves, Paula M; Coroadinha, Ana S

2015-09-01

Vaccination is one of the most effective interventions in global health. The worldwide vaccination programs significantly reduced the number of deaths caused by infectious agents. A successful example was the eradication of smallpox in 1979 after two centuries of vaccination campaigns. Since the first variolation administrations until today, the knowledge on immunology has increased substantially. This knowledge combined with the introduction of cell culture and DNA recombinant technologies revolutionized vaccine design. This review will focus on vaccines against human viral pathogens, recent developments on vaccine design and cell substrates used for their manufacture. While the production of attenuated and inactivated vaccines requires the use of the respective permissible cell substrates, the production of recombinant antigens, virus-like particles, vectored vaccines and chimeric vaccines requires the use - and often the development - of specific cell lines. Indeed, the development of novel modern viral vaccine designs combined with, the stringent safety requirements for manufacture, and the better understanding on animal cell metabolism and physiology are increasing the awareness on the importance of cell line development and engineering areas. A new era of modern vaccinology is arriving, offering an extensive toolbox to materialize novel and creative ideas in vaccine design and its manufacture. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Targeting Herpes Simplex Virus-1 gD by a DNA Aptamer Can Be an Effective New Strategy to Curb Viral Infection

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Tejabhiram Yadavalli

2017-12-01

Full Text Available Herpes simplex virus type 1 (HSV-1 is an important factor for vision loss in developed countries. A challenging aspect of the ocular infection by HSV-1 is that common treatments, such as acyclovir, fail to provide effective topical remedies. Furthermore, it is not very clear whether the viral glycoproteins, required for HSV-1 entry into the host, can be targeted for an effective therapy against ocular herpes in vivo. Here, we demonstrate that HSV-1 envelope glycoprotein gD, which is essential for viral entry and spread, can be specifically targeted by topical applications of a small DNA aptamer to effectively control ocular infection by the virus. Our 45-nt-long DNA aptamer showed high affinity for HSV-1 gD (binding affinity constant [Kd] = 50 nM, which is strong enough to disrupt the binding of gD to its cognate host receptors. Our studies showed significant restriction of viral entry and replication in both in vitro and ex vivo studies. In vivo experiments in mice also resulted in loss of ocular infection under prophylactic treatment and statistically significant lower infection under therapeutic modality compared to random DNA controls. Thus, our studies validate the possibility that targeting HSV-1 entry glycoproteins, such as gD, can locally reduce the spread of infection and define a novel DNA aptamer-based approach to control HSV-1 infection of the eye.

Features of Intestinal Microbiocenosis in Viral Hepatitis and Possibilities of Its Correction

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I.B. Yershova

2014-04-01

Full Text Available The article deals with the correction of intestinal microbiocenosis in patients with viral hepatitis. There is presented a study on the state of the intestinal microflora in children who had hepatitis A virus (HAV, patients with chronic viral hepatitis B or C (HBV, HCV. Materials and Methods. The study involved 39 children: 12 persons who had HAV, 19 persons with chronic HCV, 8 persons with chronic HBV infection. All the children were randomized into two groups. The first group included 18 children who, along with basic therapy, received probiotic agent Subalin, the second group — 21 people who received only basic therapy. Results and Discussion. Inclusion in the complex treatment of probiotic agent Subalin allowed to stop such clinical symptoms as asthenovegetative syndrome, chronic intoxication syndrome, to reduce dyspeptic syndrome and hepatomegaly, as well as to restore intestinal microflora and to eliminate pathogenic and opportunistic microorganisms. We noted high tolerability of Subalin and no side effects. Conclusions. Application of Subalin in the complex therapy of children with viral hepatitis eliminates intoxication syndrome and contributes to the rapid regression of clinical symptoms, the recovery of the intestinal microflora, normalizes the immune status.

Health information technology interventions enhance care completion, engagement in HIV care and treatment, and viral suppression among HIV-infected patients in publicly funded settings.

Science.gov (United States)

Shade, Starley B; Steward, Wayne T; Koester, Kimberly A; Chakravarty, Deepalika; Myers, Janet J

2015-04-01

The National HIV/AIDS Strategy (NHAS) emphasizes the use of technology to facilitate coordination of comprehensive care for people with HIV. We examined the effect of six health information technology (HIT) interventions in a Ryan White-funded Special Projects of National Significance (SPNS) on care completion services, engagement in HIV care, and viral suppression. Interventions included use of surveillance data to identify out-of-care individuals, extending access to electronic health records to support service providers, use of electronic laboratory ordering and prescribing, and development of a patient portal. Data from a sample of electronic patient records from each site were analyzed to assess changes in utilization of comprehensive care (prevention screening, support service utilization), engagement in primary HIV medical care (receipt of services and use of antiretroviral therapy), and viral suppression. We used weighted generalized estimating equations to estimate outcomes while accounting for the unequal contribution of data and differences in the distribution of patient characteristics across sites and over time. We observed statistically significant changes in the desired direction in comprehensive care utilization and engagement in primary care outcomes targeted by each site. Five of six sites experienced statistically significant increases in viral suppression. These results provide additional support for the use of HIT as a valuable tool for achieving the NHAS goal of providing comprehensive care for all people living with HIV. HIT has the potential to increase utilization of services, improve health outcomes for people with HIV, and reduce community viral load and subsequent transmission of HIV. © The Author 2014. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com For affiliation see end of article.

Viral hepatitis screening in transgender patients undergoing gender identity hormonal therapy.

Science.gov (United States)

Mangla, Neeraj; Mamun, Rifat; Weisberg, Ilan S

2017-11-01

Viral hepatitis is a global health issue and can lead to cirrhosis, liver failure, and hepatocellular carcinoma. Guidelines for viral hepatitis screening in the transgender population do not exist. Transgender patients may be at higher risk for contracting viral hepatitis due to socioeconomic and behavioral factors. The aim of this study was to measure the quality of screening, prevalence, and susceptibility of viral hepatitis, and to identify barriers to screening in transgender patients undergoing gender identity hormonal therapy. LGBTQ-friendly clinic visits from transgender patients older than 18 years in New York City from 2012 to 2015 were reviewed. Approximately 13% of patients were screened for any viral hepatitis on initial consultation. Screening rates for hepatitis C virus (HCV), hepatitis B virus (HBV), and hepatitis A virus (HAV) at any point were 27, 22, and 20%. HAV screening was performed in 28% of the female to male (FtM) patients and 16% of male to female (MtF) (P0.05). Prevalence of HCV, HBV, and HIV in FtM was 0, 0, and 0.44% and that in MtF was 1.78, 0.89, and 1.78%, respectively. Percentage of patients immune to hepatitis A in FtM and MtF subgroups were 55 and 47% (P>0.05). Percentage of patients immune to HBV in FtM and MtF subgroups were 54 and 48% (P>0.05). This study indicates a significant lack of hepatitis screening in the transgender population and a concerning proportion of patients susceptible to disease.

HIV-1 viral escape in cerebrospinal fluid of subjects on suppressive antiretroviral treatment.

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Edén, Arvid; Fuchs, Dietmar; Hagberg, Lars; Nilsson, Staffan; Spudich, Serena; Svennerholm, Bo; Price, Richard W; Gisslén, Magnus

2010-12-15

Occasional cases of viral escape in cerebrospinal fluid (CSF) despite suppression of plasma human immunodeficiency virus type 1 (HIV-1) RNA have been reported. We investigated CSF viral escape in subjects treated with commonly used antiretroviral therapy regimens in relation to intrathecal immune activation and central nervous system penetration effectiveness (CPE) rank. Sixty-nine neurologically asymptomatic subjects treated with antiretroviral therapy >6 months and plasma HIV-1 RNA penetration effectiveness rank was not a significant predictor of detectable CSF virus or CSF neopterin levels. Viral escape in CSF is more common than previously reported, suggesting that low-grade central nervous system infection may continue in treated patients. Although these findings need extension in longitudinal studies, they suggest the utility of monitoring CSF responses, as new treatment combinations and strategies modify clinical practice.

Exploring and Prioritizing Factors Influencing Viral Marketing in the Context of Mobile Application

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Nastaran Hajiheidari

2017-06-01

Full Text Available Viral marketing, relying on word of mouth principle is an advertising or a way to publish it on the Internet or mobile networks. The main objective of this article is to explore and prioritize important factors affecting viral marketing in the context of mobile applications. Meta-synthesis technique was used to explore the important factors affecting viral marketing and then using Fuzzy Delphi to determine the significance of the factors. The population of this study in the quantitative section was experts working in the field of viral marketing in the mobile application industry who have been selected by snowball sampling method. In the meantime, 30 experts were selected. The results of meta-synthesis method showed 26 important factors. By using Fuzzy Delphi, 12 factors including speed of message, attractiveness of message, ability to communicate with the product, morality, reliability of the source or validity, personality of the recipient, motivations of people, emotions of people, culture, brand reputation, brand strength as well as brand image were the most important factors

Optimizing viral and non-viral gene transfer methods for genetic modification of porcine mesenchymal stem cells

DEFF Research Database (Denmark)

Stiehler, Maik; Duch, Mogens; Mygind, Tina

2006-01-01

INTRODUCTION: Mesenchymal stem cells (MSCs) provide an excellent source of pluripotent progenitor cells for tissue-engineering applications due to their proliferation capacity and differentiation potential. Genetic modification of MSCs with genes encoding tissue-specific growth factors...... viral and non-viral ex vivo gene delivery systems with respect to gene transfer efficiency, maintenance of transgene expression, and safety issues using primary porcine MSCs as target cells. MATERIALS AND METHODS: MSCs were purified from bone marrow aspirates from the proximal tibiae of four 3-month......-old Danish landrace pigs by Ficoll step gradient separation and polystyrene adherence technique. Vectors expressing enhanced green fluorescent protein (eGFP) and human bone morphogenetic protein-2 (BMP-2) were transferred to the cells by different non-viral methods and by use of recombinant adeno...

Possible Relevance of Receptor-Receptor Interactions between Viral- and Host-Coded Receptors for Viral-Induced Disease

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Luigi F. Agnati

2007-01-01

Full Text Available It has been demonstrated that some viruses, such as the cytomegalovirus, code for G-protein coupled receptors not only to elude the immune system, but also to redirect cellular signaling in the receptor networks of the host cells. In view of the existence of receptor-receptor interactions, the hypothesis is introduced that these viral-coded receptors not only operate as constitutively active monomers, but also can affect other receptor function by interacting with receptors of the host cell. Furthermore, it is suggested that viruses could also insert not single receptors (monomers, but clusters of receptors (receptor mosaics, altering the cell metabolism in a profound way. The prevention of viral receptor-induced changes in host receptor networks may give rise to novel antiviral drugs that counteract viral-induced disease.

Viral DNA Sensors IFI16 and Cyclic GMP-AMP Synthase Possess Distinct Functions in Regulating Viral Gene Expression, Immune Defenses, and Apoptotic Responses during Herpesvirus Infection.

Science.gov (United States)

Diner, Benjamin A; Lum, Krystal K; Toettcher, Jared E; Cristea, Ileana M

2016-11-15

The human interferon-inducible protein IFI16 is an important antiviral factor that binds nuclear viral DNA and promotes antiviral responses. Here, we define IFI16 dynamics in space and time and its distinct functions from the DNA sensor cyclic dinucleotide GMP-AMP synthase (cGAS). Live-cell imaging reveals a multiphasic IFI16 redistribution, first to viral entry sites at the nuclear periphery and then to nucleoplasmic puncta upon herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV) infections. Optogenetics and live-cell microscopy establish the IFI16 pyrin domain as required for nuclear periphery localization and oligomerization. Furthermore, using proteomics, we define the signature protein interactions of the IFI16 pyrin and HIN200 domains and demonstrate the necessity of pyrin for IFI16 interactions with antiviral proteins PML and cGAS. We probe signaling pathways engaged by IFI16, cGAS, and PML using clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9-mediated knockouts in primary fibroblasts. While IFI16 induces cytokines, only cGAS activates STING/TBK-1/IRF3 and apoptotic responses upon HSV-1 and HCMV infections. cGAS-dependent apoptosis upon DNA stimulation requires both the enzymatic production of cyclic dinucleotides and STING. We show that IFI16, not cGAS or PML, represses HSV-1 gene expression, reducing virus titers. This indicates that regulation of viral gene expression may function as a greater barrier to viral replication than the induction of antiviral cytokines. Altogether, our findings establish coordinated and distinct antiviral functions for IFI16 and cGAS against herpesviruses. How mammalian cells detect and respond to DNA viruses that replicate in the nucleus is poorly understood. Here, we decipher the distinct functions of two viral DNA sensors, IFI16 and cGAS, during active immune signaling upon infection with two herpesviruses, herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV). We show that IFI16

Immunity: Insect Immune Memory Goes Viral.

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Ligoxygakis, Petros

2017-11-20

Adaptive memory in insect immunity has been controversial. In this issue, Andino and co-workers propose that acquisition of viral sequences in the host genome gives rise to anti-sense, anti-viral piRNAs. Such sequences can be regarded as both a genomic archive of past infections and as an armour of potential heritable memory. Copyright © 2017 Elsevier Ltd. All rights reserved.

A highly intensified ART regimen induces long-term viral suppression and restriction of the viral reservoir in a simian AIDS model.

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Iart Luca Shytaj

Full Text Available Stably suppressed viremia during ART is essential for establishing reliable simian models for HIV/AIDS. We tested the efficacy of a multidrug ART (highly intensified ART in a wide range of viremic conditions (10³-10⁷ viral RNA copies/mL in SIVmac251-infected rhesus macaques, and its impact on the viral reservoir. Eleven macaques in the pre-AIDS stage of the disease were treated with a multidrug combination (highly intensified ART consisting of two nucleosidic/nucleotidic reverse transcriptase inhibitors (emtricitabine and tenofovir, an integrase inhibitor (raltegravir, a protease inhibitor (ritonavir-boosted darunavir and the CCR5 blocker maraviroc. All animals stably displayed viral loads below the limit of detection of the assay (i.e. <40 RNA copies/mL after starting highly intensified ART. By increasing the sensitivity of the assay to 3 RNA copies/mL, viral load was still below the limit of detection in all subjects tested. Importantly, viral DNA resulted below the assay detection limit (<2 copies of DNA/5*10⁵ cells in PBMCs and rectal biopsies of all animals at the end of the follow-up, and in lymph node biopsies from the majority of the study subjects. Moreover, highly intensified ART decreased central/transitional memory, effector memory and activated (HLA-DR⁺ effector memory CD4⁺ T-cells in vivo, in line with the role of these subsets as the main cell subpopulations harbouring the virus. Finally, treatment with highly intensified ART at viral load rebound following suspension of a previous anti-reservoir therapy eventually improved the spontaneous containment of viral load following suspension of the second therapeutic cycle, thus leading to a persistent suppression of viremia in the absence of ART. In conclusion, we show, for the first time, complete suppression of viral load by highly intensified ART and a likely associated restriction of the viral reservoir in the macaque AIDS model, making it a useful platform for testing

Integration, viral charge and E2 mRNA levels in the progresion of intraepitelial cervical lesions

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Esperanza Trujillo

2018-01-01

Full Text Available It is important to distinguish among squamous intraepithelial lesions (SIL those associated with increased risk cervical cancer. Our aim was to evaluate if the expression level of gen E2 in women with SIL and evidence of viral integration is associated to the grade of lesion. Cervical scrapes HPV16 positive from 19 women with normal histology, 45 women with low-grade SIL (LSIL and 45 women with high-grade SIL (HSIL were analyzed. Real-time PCR was used to quantify the mRNA of E2 and E2 and E6 genes to calculate viral load (E6 and the ratio E2/E6 to assess viral integration. Similar frequencies of E2 expression were found in LSIL and HSIL15/45 (33 %, the frequency in women without SIL was lower 3/19 (15.8 %, and all cases with E2 gene expression had mixed episomal and integrated viral DNA. The viral load increased significantly with the grade of SIL (p= 0.049, while E2/E6 ratio decreased (p=0.049. The ROC analysis showed low capacity of the three viral parameters analyzed to distinguish between low and high grade SIL. In conclusion although SIL with mixed and integrated viral DNA with E2 expression could be at lower risk of progression, and viral load and integration were associated with higher severity of the lesion, its clinical value as biomarkers of HSIL is limited.

Modern marketing approach: Concept of viral marketing

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Mihailović Lidija B.

2017-01-01

Full Text Available Today, viral marketing is one of the most effective forms of marketing and it can be used to raise awareness about the product/service of a specific company. This type of marketing thrives in a modern environment, where final users (buyers/clients dominate by spreading messages within themselves. Boosted by the advantages that modern technology brings, viral marketing is booming in the online world. For the first time, small brands have a chance to make their appearance in the global market ad challenge the dominating position of the historically top brands. All they need is content that draws attention and modern, digital culture will help spread their message. Viral marketing is the future. And with the growth of social media and other channels, marketing managers need to be careful, because it is a thin line between a good and a bad (backfired viral campaign.

Membrane Bioreactor-Based Wastewater Treatment Plant in Saudi Arabia: Reduction of Viral Diversity, Load, and Infectious Capacity

KAUST Repository

Jumat, Muhammad; Hasan, Nur; Subramanian, Poorani; Heberling, Colin; Colwell, Rita; Hong, Pei-Ying

2017-01-01

(AdV) and Enteroviruses (EV) were enumerated using digital polymerase chain reaction (dPCR) and assessed for infectivity using fluorescence-based infection assays. MBR treatment was successful in reducing viral diversity. Plant viruses remained

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.

The contribution of Ebola viral load at admission and other patient characteristics to mortality in a Médecins Sans Frontières (MSF) Ebola Case Management Centre (CMC), Kailahun, Sierra Leone, June -October, 2014.

LENUS (Irish Health Repository)

Fitzpatrick, Gabriel

2015-05-22

This paper describes patient characteristics, including Ebola viral load, associated with mortality in an MSF Ebola case management centre. Out of 780 admissions between June and October 2014, 525 (67%) were positive for Ebola with a known outcome. The crude mortality rate was 51% (270\\/525). Ebola viral load (whole blood sample) data was available on 76% (397\\/525) of patients. Univariate analysis indicated viral load at admission, age, symptom duration prior to admission and distance travelled to the CMC were associated with mortality (p value<0.05). The multivariable model predicted mortality in those with a viral load at admission greater than 10 million copies per millilitre (p value<0.05, Odds Ratio>10), aged 50 years or more (p value=0.08, Odds Ratio=2) and symptom duration prior to admission less than 5 days (p value=0.14). The presence of confusion, diarrhoea and conjunctivitis were significantly higher (p value<0.05) in Ebola patients who died. These findings highlight the importance viral load at admission has on mortality outcomes and could be used to cohort cases with viral loads greater than 10 million copies into dedicated wards with more intensive medical support to further reduce mortality.

Retargeting of rat parvovirus H-1PV to cancer cells through genetic engineering of the viral capsid.

Science.gov (United States)

Allaume, Xavier; El-Andaloussi, Nazim; Leuchs, Barbara; Bonifati, Serena; Kulkarni, Amit; Marttila, Tiina; Kaufmann, Johanna K; Nettelbeck, Dirk M; Kleinschmidt, Jürgen; Rommelaere, Jean; Marchini, Antonio

2012-04-01

The rat parvovirus H-1PV is a promising anticancer agent given its oncosuppressive properties and the absence of known side effects in humans. H-1PV replicates preferentially in transformed cells, but the virus can enter both normal and cancer cells. Uptake by normal cells sequesters a significant portion of the administered viral dose away from the tumor target. Hence, targeting H-1PV entry specifically to tumor cells is important to increase the efficacy of parvovirus-based treatments. In this study, we first found that sialic acid plays a key role in H-1PV entry. We then genetically engineered the H-1PV capsid to improve its affinity for human tumor cells. By analogy with the resolved crystal structure of the closely related parvovirus minute virus of mice, we developed an in silico three-dimensional (3D) model of the H-1PV wild-type capsid. Based on this model, we identified putative amino acids involved in cell membrane recognition and virus entry at the level of the 2-fold axis of symmetry of the capsid, within the so-called dimple region. In situ mutagenesis of these residues significantly reduced the binding and entry of H-1PV into permissive cells. We then engineered an entry-deficient viral capsid and inserted a cyclic RGD-4C peptide at the level of its 3-fold axis spike. This peptide binds α(v)β(3) and α(v)β(5) integrins, which are overexpressed in cancer cells and growing blood vessels. The insertion of the peptide rescued viral infectivity toward cells overexpressing α(v)β(5) integrins, resulting in the efficient killing of these cells by the reengineered virus. This work demonstrates that H-1PV can be genetically retargeted through the modification of its capsid, showing great promise for a more efficient use of this virus in cancer therapy.

ViralEpi v1.0: a high-throughput spectrum of viral epigenomic methylation profiles from diverse diseases.

Science.gov (United States)

Khan, Mohd Shoaib; Gupta, Amit Kumar; Kumar, Manoj

2016-01-01

To develop a computational resource for viral epigenomic methylation profiles from diverse diseases. Methylation patterns of Epstein-Barr virus and hepatitis B virus genomic regions are provided as web platform developed using open source Linux-Apache-MySQL-PHP (LAMP) bundle: programming and scripting languages, that is, HTML, JavaScript and PERL. A comprehensive and integrated web resource ViralEpi v1.0 is developed providing well-organized compendium of methylation events and statistical analysis associated with several diseases. Additionally, it also facilitates 'Viral EpiGenome Browser' for user-affable browsing experience using JavaScript-based JBrowse. This web resource would be helpful for research community engaged in studying epigenetic biomarkers for appropriate prognosis and diagnosis of diseases and its various stages.

Defibrillator charging before rhythm analysis significantly reduces hands-off time during resuscitation

DEFF Research Database (Denmark)

Hansen, L. K.; Folkestad, L.; Brabrand, M.

2013-01-01

BACKGROUND: Our objective was to reduce hands-off time during cardiopulmonary resuscitation as increased hands-off time leads to higher mortality. METHODS: The European Resuscitation Council (ERC) 2005 and ERC 2010 guidelines were compared with an alternative sequence (ALT). Pulseless ventricular...... physicians were included. All had prior experience in advanced life support. Chest compressions were shorter interrupted using ALT (mean, 6.7 vs 13.0 seconds). Analyzing data for ventricular tachycardia scenarios only, hands-off time was shorter using ALT (mean, 7.1 vs 18.2 seconds). In ERC 2010 vs ALT, 12...... physicians were included. Two physicians had not prior experience in advanced life support. Hands-off time was reduced using ALT (mean, 3.9 vs 5.6 seconds). Looking solely at ventricular tachycardia scenarios, hands-off time was shortened using ALT (mean, 4.5 vs 7.6 seconds). No significant reduction...

Effect of Lopinavir and Nevirapine Concentrations on Viral Outcomes in Protease Inhibitor-experienced HIV-infected Children.

Science.gov (United States)

Moholisa, Retsilisitsoe R; Schomaker, Michael; Kuhn, Louise; Castel, Sandra; Wiesner, Lubbe; Coovadia, Ashraf; Strehlau, Renate; Patel, Faeezah; Pinillos, Francoise; Abrams, Elaine J; Maartens, Gary; McIlleron, Helen

2016-12-01

Adequate exposure to antiretroviral drugs is necessary to achieve and sustain viral suppression. However, the target antiretroviral concentrations associated with long-term viral suppression have not been adequately defined in children. We assessed the relationship between plasma lopinavir or nevirapine concentrations and the risk of subsequent viremia in children initially suppressed on antiretroviral therapy. After an induction phase of antiretroviral treatment, 195 children with viral suppression (viral load ≤400 copies/mL) were randomized to continue a lopinavir/ritonavir-based regimen or to switch to a nevirapine-based regimen (together with lamivudine and stavudine). Viral load and lopinavir or nevirapine concentrations were measured at clinic visits 4, 8, 12, 16, 20, 24, 36, 52, 64 and 76 weeks post randomization. Cox multiple failure event models were used to estimate the effects of drug concentrations on the hazard of viremia (viral load >50 copies/mL) RESULTS:: At randomization, the median (interquartile range) age, CD4 T-Lymphocyte percentage, weight-for-age and weight-for-height z scores were 19 (16-24) months, 29% (23-37), -0.6 (-1.3 to 0.2) and -3.2 (-4.1 to -2.1), respectively. The proportion of children with viral load 51-400 copies/mL at randomization was 43%. The hazard of subsequent viremia during follow-up was increased for lopinavir concentrations <1 versus ≥1 mg/L [adjusted hazard ratio 0.62 (95% confidence interval, 0.40-0.94)] and for children with viral loads 51-400 copies/mL at randomization. Nevirapine concentrations were not significantly associated with subsequent viremia. Plasma lopinavir concentrations predicted viral outcomes in children receiving lopinavir-based antiretroviral therapy. Our findings support a minimum target concentration of ≥1 mg/L of lopinavir to ensure sustained viral suppression.

RUNX2 Mediates Plasmacytoid Dendritic Cell Egress from the Bone Marrow and Controls Viral Immunity

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Michaël Chopin

2016-04-01

Full Text Available Plasmacytoid dendritic cells (pDCs represent a unique immune cell type that responds to viral nucleic acids through the rapid production of type I interferons. Within the hematopoietic system, the transcription factor RUNX2 is exclusively expressed in pDCs and is required for their peripheral homeostasis. Here, we show that RUNX2 plays an essential role in promoting pDC localization and function. RUNX2 is required for the appropriate expression of the integrin-mediated adhesion machinery, as well as for the down-modulation of the chemokine receptor CXCR4, which allows pDC egress into the circulation. RUNX2 also facilitates the robust response to viral infection through the control of IRF7, the major regulator of type I interferon production. Mice lacking one copy of Runx2 have reduced numbers of peripheral pDCs and IFN-α expression, which might contribute to the reported difficulties of individuals with cleidocranial dysplasia, who are haploinsufficient for RUNX2, to clear viral infections.

P53-mediated rapid induction of apoptosis conveys resistance to viral infection in Drosophila melanogaster.

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Bo Liu

2013-02-01

Full Text Available Arthropod-borne pathogens account for millions of deaths each year. Understanding the genetic mechanisms controlling vector susceptibility to pathogens has profound implications for developing novel strategies for controlling insect-transmitted infectious diseases. The fact that many viruses carry genes that have anti-apoptotic activity has long led to the hypothesis that induction of apoptosis could be a fundamental innate immune response. However, the cellular mechanisms mediating the induction of apoptosis following viral infection remained enigmatic, which has prevented experimental verification of the functional significance of apoptosis in limiting viral infection in insects. In addition, studies with cultured insect cells have shown that there is sometimes a lack of apoptosis, or the pro-apoptotic response happens relatively late, thus casting doubt on the functional significance of apoptosis as an innate immunity. Using in vivo mosquito models and the native route of infection, we found that there is a rapid induction of reaper-like pro-apoptotic genes within a few hours following exposure to DNA or RNA viruses. Recapitulating a similar response in Drosophila, we found that this rapid induction of apoptosis requires the function of P53 and is mediated by a stress-responsive regulatory region upstream of reaper. More importantly, we showed that the rapid induction of apoptosis is responsible for preventing the expression of viral genes and blocking the infection. Genetic changes influencing this rapid induction of reaper-like pro-apoptotic genes led to significant differences in susceptibility to viral infection.

Herpesviruses viral loads and levels of proinflammatory cytokines in apical periodontitis.

Science.gov (United States)

Jakovljevic, A; Knezevic, A; Nikolic, N; Soldatovic, I; Jovanovic, T; Milasin, J; Andric, M

2018-07-01

This study aimed to analyse Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) viral loads in symptomatic and asymptomatic apical periodontitis lesions, to determine levels of TNF-α, IL-1β and IL-6 in these lesions and to investigate a possible correlation between herpesviral copy numbers and levels of proinflammatory cytokines. A total of 100 samples of apical periodontitis were subjected to HCMV and EBV copy numbers analysis by nested polymerase chain reaction (PCR) and TaqMan real-time PCR. The concentrations of TNF-α, IL-1β and IL-6 were determined by ELISA method. SPSS software was used for statistical analysis. There were no significant differences in the occurrence of EBV and HCMV between symptomatic and asymptomatic periapical lesions (p = .686, p = .879, respectively). Only 12 of 74 EBV (16.2%) and four of 54 HCMV (13.5%) nested PCR-positive samples showed increased viral copy numbers above the limit of 125 copies/ml. There was no significant correlation between the levels of analysed proinflammatory cytokines and herpesviral copy numbers in our sample. The observed low viral loads point to a relatively rare occurrence of active EBV and HCMV infection in our sample. Latent herpesviral infection does not enhance the production of investigated proinflammatory cytokines. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.

Treating respiratory viral diseases with chemically modified, second generation intranasal siRNAs.

Science.gov (United States)

Barik, Sailen

2009-01-01

Chemically synthesized short interfering RNA (siRNA) of pre-determined sequence has ushered a new era in the application of RNA interference (RNAi) against viral genes. We have paid particular attention to respiratory viruses that wreak heavy morbidity and mortality worldwide. The clinically significant ones include respiratory syncytial virus (RSV), parainfluenza virus (PIV) and influenza virus. As the infection by these viruses is clinically restricted to the respiratory tissues, mainly the lungs, the logical route for the application of the siRNA was also the same, i.e., via the nasal route. Following the initial success of intranasal siRNA against RSV, second-generation siRNAs were made against the viral polymerase large subunit (L) that were chemically modified and screened for improved stability, activity and pharmacokinetics. 2'-O-methyl (2'-O-Me) and 2'-deoxy-2'-fluoro (2'-F) substitutions in the ribose ring were incorporated in different positions of the sense and antisense strands and the resultant siRNAs were tested with various transfection reagents intranasally against RSV. Based on these results, we propose the following consensus for designing intranasal antiviral siRNAs: (i) modified 19-27 nt long double-stranded siRNAs are functional in the lung, (ii) excessive 2'-OMe and 2'-F modifications in either or both strands of these siRNAs reduce efficacy, and (iii) limited modifications in the sense strand are beneficial, although their precise efficacy may be position-dependent.

Viral haemorrhagic fever and vascular alterations.

Science.gov (United States)

Aleksandrowicz, P; Wolf, K; Falzarano, D; Feldmann, H; Seebach, J; Schnittler, H

2008-02-01

Pathogenesis of viral haemorrhagic fever (VHF) is closely associated with alterations of the vascular system. Among the virus families causing VHF, filoviruses (Marburg and Ebola) are the most fatal, and will be focused on here. After entering the body, Ebola primarily targets monocytes/macrophages and dendritic cells. Infected dendritic cells are largely impaired in their activation potency, likely contributing to the immune suppression that occurs during filovirus infection. Monocytes/macrophages, however, immediately activate after viral contact and release reasonable amounts of cytokines that target the vascular system, particularly the endothelial cells. Some underlying molecular mechanisms such as alteration of the vascular endothelial cadherin/catenin complex, tyrosine phosphorylation, expression of cell adhesion molecules, tissue factor and the effect of soluble viral proteins released from infected cells to the blood stream will be discussed.

Time to viral load suppression in antiretroviral-naive and -experienced HIV-infected pregnant women on highly active antiretroviral therapy: implications for pregnant women presenting late in gestation.

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Aziz, N; Sokoloff, A; Kornak, J; Leva, N V; Mendiola, M L; Levison, J; Feakins, C; Shannon, M; Cohan, D

2013-11-01

To compare time to achieve viral load HIV-infected antiretroviral (ARV) -naive versus ARV-experienced pregnant women on highly active antiretroviral therapy (HAART). Retrospective cohort study. Three university medical centers, USA. HIV-infected pregnant women initiated or restarted on HAART during pregnancy. We calculated time to viral load HIV-infected pregnant women on HAART who reported at least 50% adherence, stratifying based on previous ARV exposure history. Time to HIV viral load HIV-infected pregnant women, comprising 76 ARV-naive and 62 ARV-experienced. Ninety-three percent of ARV-naive women achieved a viral load HIV log10 viral load was associated with a later time of achieving viral load HIV log10 viral load was associated with a longer time of achieving viral load Pregnant women with ≥50% adherence, whether ARV-naive or ARV-experienced, on average achieve a viral load HIV log10 viral load were all statistically significant predictors of earlier time to achieve viral load <400 copies/ml and <1000 copies/ml. Increased CD4 count was statistically significant as a predictor of earlier time to achieve viral load <1000 copies/ml. © 2013 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2013 RCOG.

Early viral replication and induced or constitutive immunity in rainbow trout families with differential resistance to Infectious hematopoietic necrosis virus (IHNV)

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Purcell, M.K.; LaPatra, S.E.; Woodson, J.C.; Kurath, G.; Winton, J.R.

2010-01-01

The main objective of this study was to assess correlates of innate resistance in rainbow trout full-sibling families that differ in susceptibility to Infectious hematopoietic necrosis virus (IHNV). As part of a commercial breeding program, full-sibling families were challenged with IHNV by waterborne exposure at the 1 g size to determine susceptibility to IHNV. Progeny from select families (N = 7 families) that varied in susceptibility (ranging from 32 to 90% cumulative percent mortality (CPM)) were challenged again at the 10 g size by intra-peritoneal injection and overall mortality, early viral replication and immune responses were evaluated. Mortality challenges included 20–40 fish per family while viral replication and immune response studies included 6 fish per family at each time point (24, 48 and 72 h post-infection (hpi)). CPM at the 1 g size was significantly correlated with CPM at the 10 g size, indicating that inherent resistance was a stable trait irrespective of size. In the larger fish, viral load was measured by quantitative reverse-transcriptase PCR in the anterior kidney and was a significant predictor of family disease outcome at 48 hpi. Type I interferon (IFN) transcript levels were significantly correlated with an individual's viral load at 48 and 72 hpi, while type II IFN gene expression was significantly correlated with an individual's viral load at 24 and 48 hpi. Mean family type I but not type II IFN gene expression was weakly associated with susceptibility at 72 hpi. There was no association between mean family susceptibility and the constitutive expression of a range of innate immune genes (e.g. type I and II IFN pathway genes, cytokine and viral recognition receptor genes). The majority of survivors from the challenge had detectable serum neutralizing antibody titers but no trend was observed among families. This result suggests that even the most resistant families experienced sufficient levels of viral replication to trigger specific

Nasopharyngeal polymicrobial colonization during health, viral upper respiratory infection and upper respiratory bacterial infection.

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Xu, Qingfu; Wischmeyer, Jareth; Gonzalez, Eduardo; Pichichero, Michael E

2017-07-01

We sought to understand how polymicrobial colonization varies during health, viral upper respiratory infection (URI) and acute upper respiratory bacterial infection to understand differences in infection-prone vs. non-prone patients. Nasopharyngeal (NP) samples were collected from 74 acute otitis media (AOM) infection-prone and 754 non-prone children during 2094 healthy visits, 673 viral URI visits and 631 AOM visits. Three otopathogens Streptococcus pneumoniae (Spn), Nontypeable Haemophilus influenzae (NTHi), and Moraxella catarrhalis (Mcat) were identified by culture. NP colonization rates of multiple otopathogens during health were significantly lower than during viral URI, and during URI they were lower than at onset of upper respiratory bacterial infection in both AOM infection-prone and non-prone children. AOM infection-prone children had higher polymicrobial colonization rates than non-prone children during health, viral URI and AOM. Polymicrobial colonization rates of AOM infection-prone children during health were equivalent to that of non-prone children during viral URI, and during viral URI were equivalent to that of non-prone during AOM infection. Spn colonization was positively associated with NTHi and Mcat colonization during health, but negatively during AOM infection. The infection-prone patients more frequently have multiple potential bacterial pathogens in the NP than the non-prone patients. Polymicrobial interaction in the NP differs during health and at onset of infection. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

A novel host-proteome signature for distinguishing between acute bacterial and viral infections.

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Kfir Oved

, times from symptom onset, and pathogens (AUCs 0.87-1.0. The accurate differential diagnosis provided by this novel combination of viral- and bacterial-induced proteins has the potential to improve management of patients with acute infections and reduce antibiotic misuse.

Hepatitis B viral factors and treatment responses in chronic hepatitis B

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Chih-Lin Lin

2013-06-01

Full Text Available Baseline and on-treatment hepatitis B viral factors are reported to affect treatment responses. A lower baseline hepatitis B virus (HBV DNA level is a strong predictor of the response to antiviral therapy. HBV genotype A/B patients have better responses to interferon-based therapy than those with genotypes C/D. Regarding the association of HBV mutants with responses to antiviral therapy, current evidence is limited. On-treatment viral suppression is the most important predictor of response to nucleoside analogs. On-treatment hepatitis B surface antigen decline is significantly associated with response to pegylated interferon. In the future, individualized therapy should be based on treatment efficacy, adverse effects, baseline and on-treatment predictors of antiviral therapy.

Baicalin benefits the anti-HBV therapy via inhibiting HBV viral RNAs.

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Huang, Hai; Zhou, Wei; Zhu, Haiyan; Zhou, Pei; Shi, Xunlong

2017-05-15

Although current antiviral treatments (nucleoside analogs, NAs) for chronic hepatitis B virus (HBV) infection are effective in suppressing HBV-DNA replication, their clinical outcomes can be compromised by the increasing drug resistance and the inefficiency in promoting HBsAg/HBeAg seroconversion. In this study, we will explore possible effects and mechanism of a natural product baicalin (BA) with the anti-HBV efficacy of entecavir (ETV), a first-line anti-HBV drug, in HBV-DNA, HBsAg/HBeAg seroconversion and drug-resistance. The co-effects of BA and ETV were conducted in wild-type/NA-resistance mutant HBV cell lines and DHBV-infected duckling models. HBV-DNA/RNAs, HBsAg/HBeAg, host factors (hepatocyte nuclear factors) were explored for possible anti-HBV mechanism. BA could significantly enhance and reduced HBsAg and HBeAg in hepG2.2.15, a wild-type HBV cell line. Co-treatment of BA and ETV had a more dramatic effect in NA-resistant HBV rtM204V/rtLl80M transfected hepG2 cells. Our study further revealed that BA mainly inhibited the production of HBV RNAs (3.5, 2.4, 2.1kb), the templates for viral proteins and HBV-DNA synthesis. BA blocked HBV RNAs transcription possibly by down-regulating transcription and expression of HBV replication dependent hepatocyte nuclear factors (HNF1α and HNF4α). Thus, BA may benefit the anti-HBV therapy via inhibiting HBV viral RNAs. Copyright © 2017 Elsevier Inc. All rights reserved.

Topical herpes simplex virus 2 (HSV-2) vaccination with human papillomavirus vectors expressing gB/gD ectodomains induces genital-tissue-resident memory CD8+ T cells and reduces genital disease and viral shedding after HSV-2 challenge.

Science.gov (United States)

Çuburu, Nicolas; Wang, Kening; Goodman, Kyle N; Pang, Yuk Ying; Thompson, Cynthia D; Lowy, Douglas R; Cohen, Jeffrey I; Schiller, John T

2015-01-01

No herpes simplex virus 2 (HSV-2) vaccine has been licensed for use in humans. HSV-2 glycoproteins B (gB) and D (gD) are targets of neutralizing antibodies and T cells, but clinical trials involving intramuscular (i.m.) injection of HSV-2 gB and gD in adjuvants have not been effective. Here we evaluated intravaginal (ivag) genetic immunization of C57BL/6 mice with a replication-defective human papillomavirus pseudovirus (HPV PsV) expressing HSV-2 gB (HPV-gB) or gD (HPV-gD) constructs to target different subcellular compartments. HPV PsV expressing a secreted ectodomain of gB (gBsec) or gD (gDsec), but not PsV expressing a cytoplasmic or membrane-bound form, induced circulating and intravaginal-tissue-resident memory CD8(+) T cells that were able to secrete gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α) as well as moderate levels of serum HSV neutralizing antibodies. Combined immunization with HPV-gBsec and HPV-gDsec (HPV-gBsec/gDsec) vaccines conferred longer survival after vaginal challenge with HSV-2 than immunization with HPV-gBsec or HPV-gDsec alone. HPV-gBsec/gDsec ivag vaccination was associated with a reduced severity of genital lesions and lower levels of viral shedding in the genital tract after HSV-2 challenge. In contrast, intramuscular vaccination with a soluble truncated gD protein (gD2t) in alum and monophosphoryl lipid A (MPL) elicited high neutralizing antibody titers and improved survival but did not reduce genital lesions and viral shedding. Vaccination combining ivag HPV-gBsec/gDsec and i.m. gD2t-alum-MPL improved survival and reduced genital lesions and viral shedding. Finally, high levels of circulating HSV-2-specific CD8(+) T cells, but not serum antibodies, correlated with reduced viral shedding. Taken together, our data underscore the potential of HPV PsV as a platform for a topical mucosal vaccine to control local manifestations of primary HSV-2 infection. Genital herpes is a highly prevalent chronic disease caused by

Rapid and highly fieldable viral diagnostic

Energy Technology Data Exchange (ETDEWEB)

McKnight, Timothy E.

2016-12-20

The present invention relates to a rapid, highly fieldable, nearly reagentless diagnostic to identify active RNA viral replication in a live, infected cells, and more particularly in leukocytes and tissue samples (including biopsies and nasal swabs) using an array of a plurality of vertically-aligned nanostructures that impale the cells and introduce a DNA reporter construct that is expressed and amplified in the presence of active viral replication.

Influence of maintained hemodialysis on viral load in patients with end-stage renal disease with HBV infection

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ZHANG Huifang

2017-07-01

Full Text Available In the patients with end-stage renal disease (ESRD with hepatitis B virus (HBV infection who underwent hemodialysis, the viral load of HBV DNA is relatively low and stable. For this phenomenon, some studies suggest that hemodialysis can reduce the HBV DNA load. The mechanism, which remains unclear, may be as follows: when HBV DNA enters the dialysate through the dialysis membrane, it was adsorbed onto the dialysis membrane; some virus particles were destroyed, and antiviral substances were produced in the course of hemodialysis. At present, there is no consensus on the mechanism responsible for the influence of maintained hemodialysis on the viral load of HBV DNA. This article reviews the factors involved in the influence of maintained hemodialysis on the viral load in ESRD patients with HBV infection and the recent progress.

Viral Evasion of Natural Killer Cell Activation

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Yi Ma

2016-04-01

Full Text Available Natural killer (NK cells play a key role in antiviral innate defenses because of their abilities to kill infected cells and secrete regulatory cytokines. Additionally, NK cells exhibit adaptive memory-like antigen-specific responses, which represent a novel antiviral NK cell defense mechanism. Viruses have evolved various strategies to evade the recognition and destruction by NK cells through the downregulation of the NK cell activating receptors. Here, we review the recent findings on viral evasion of NK cells via the impairment of NK cell-activating receptors and ligands, which provide new insights on the relationship between NK cells and viral actions during persistent viral infections.

Viral Evasion of Natural Killer Cell Activation.

Science.gov (United States)

Ma, Yi; Li, Xiaojuan; Kuang, Ersheng

2016-04-12

Natural killer (NK) cells play a key role in antiviral innate defenses because of their abilities to kill infected cells and secrete regulatory cytokines. Additionally, NK cells exhibit adaptive memory-like antigen-specific responses, which represent a novel antiviral NK cell defense mechanism. Viruses have evolved various strategies to evade the recognition and destruction by NK cells through the downregulation of the NK cell activating receptors. Here, we review the recent findings on viral evasion of NK cells via the impairment of NK cell-activating receptors and ligands, which provide new insights on the relationship between NK cells and viral actions during persistent viral infections.

Viral infection of human lung macrophages increases PDL1 expression via IFNβ.

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Karl J Staples

Full Text Available Lung macrophages are an important defence against respiratory viral infection and recent work has demonstrated that influenza-induced macrophage PDL1 expression in the murine lung leads to rapid modulation of CD8+ T cell responses via the PD1 receptor. This PD1/PDL1 pathway may downregulate acute inflammatory responses to prevent tissue damage. The aim of this study was to investigate the mechanisms of PDL1 regulation by human macrophages in response to viral infection. Ex-vivo viral infection models using influenza and RSV were established in human lung explants, isolated lung macrophages and monocyte-derived macrophages (MDM and analysed by flow cytometry and RT-PCR. Incubation of lung explants, lung macrophages and MDM with X31 resulted in mean cellular infection rates of 18%, 18% and 29% respectively. Viral infection significantly increased cell surface expression of PDL1 on explant macrophages, lung macrophages and MDM but not explant epithelial cells. Infected MDM induced IFNγ release from autologous CD8+ T cells, an effect enhanced by PDL1 blockade. We observed increases in PDL1 mRNA and IFNβ mRNA and protein release by MDM in response to influenza infection. Knockdown of IFNβ by siRNA, resulted in a 37.5% reduction in IFNβ gene expression in response to infection, and a significant decrease in PDL1 mRNA. Furthermore, when MDM were incubated with IFNβ, this cytokine caused increased expression of PDL1 mRNA. These data indicate that human macrophage PDL1 expression modulates CD8+ cell IFNγ release in response to virus and that this expression is regulated by autologous IFNβ production.

Viral infection of the marine alga Emiliania huxleyi triggers lipidome remodeling and induces the production of highly saturated triacylglycerol.

Science.gov (United States)

Malitsky, Sergey; Ziv, Carmit; Rosenwasser, Shilo; Zheng, Shuning; Schatz, Daniella; Porat, Ziv; Ben-Dor, Shifra; Aharoni, Asaph; Vardi, Assaf

2016-04-01

Viruses that infect marine photosynthetic microorganisms are major ecological and evolutionary drivers of microbial food webs, estimated to turn over more than a quarter of the total photosynthetically fixed carbon. Viral infection of the bloom-forming microalga Emiliania huxleyi induces the rapid remodeling of host primary metabolism, targeted towards fatty acid metabolism. We applied a liquid chromatography-mass spectrometry (LC-MS)-based lipidomics approach combined with imaging flow cytometry and gene expression profiling to explore the impact of viral-induced metabolic reprogramming on lipid composition. Lytic viral infection led to remodeling of the cellular lipidome, by predominantly inducing the biosynthesis of highly saturated triacylglycerols (TAGs), coupled with a significant accumulation of neutral lipids within lipid droplets. Furthermore, TAGs were found to be a major component (77%) of the lipidome of isolated virions. Interestingly, viral-induced TAGs were significantly more saturated than TAGs produced under nitrogen starvation. This study highlights TAGs as major products of the viral-induced metabolic reprogramming during the host-virus interaction and indicates a selective mode of membrane recruitment during viral assembly, possibly by budding of the virus from specialized subcellular compartments. These findings provide novel insights into the role of viruses infecting microalgae in regulating metabolism and energy transfer in the marine environment and suggest their possible biotechnological application in biofuel production. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Passive immunization of Pacific herring against viral hemorrhagic septicemia.

Science.gov (United States)

Hershberger, P.K.; Gregg, J.L.; Grady, C.A.; LaPatra, S.E.; Winton, J.R.

2011-01-01

The plasma of Pacific herring Clupea pallasii that survived laboratory-induced viral hemorrhagic septicemia (VHS) epizootics contained humoral substances that, when injected into naive animals, conferred passive immunity against the disease. Among groups exposed to viral hemorrhagic septicemia virus (VHSV), injection of donor plasma from VHS survivors resulted in significantly greater survival (50%) and significantly lower tissue titers (1.5 x 10(5) plaque-forming units [PFU]/g) than the injection of plasma from VHSV-naive donors (6% survival; 3.7 x 10(6) PFU/g). Additionally, the magnitude of the protective immune response increased during the postexposure period; plasma that was collected from survivors at 123 d postexposure (931 degree-days) provided greater protection than plasma collected from survivors at 60 d postexposure (409 degree-days). These results provide proof of concept that the VHSV exposure history of Pacific herring populations can be determined post hoc; furthermore, the results can be used as the foundation for developing additional high-throughput diagnostic techniques that may be effective at quantifying herd immunity and forecasting the potential for future VHS epizootics in populations of wild Pacific herring.

HIV Viral Load

Science.gov (United States)

... PF4 Antibody Hepatitis A Testing Hepatitis B Testing Hepatitis C Testing HER2/neu Herpes Testing High-sensitivity C-reactive Protein (hs-CRP) Histamine Histone Antibody HIV Antibody and HIV Antigen (p24) HIV Antiretroviral Drug Resistance Testing, Genotypic HIV Viral Load HLA Testing HLA- ...

Crop-associated virus reduces the rooting depth of non-crop perennial native grass more than non-crop-associated virus with known viral suppressor of RNA silencing (VSR).

Science.gov (United States)

Malmstrom, Carolyn M; Bigelow, Patrick; Trębicki, Piotr; Busch, Anna K; Friel, Colleen; Cole, Ellen; Abdel-Azim, Heba; Phillippo, Colin; Alexander, Helen M

2017-09-15

stunted annual Avena sativa L. (oats). These findings suggest that some of the diversity in grass-infecting Luteoviridae reflects viral capacity to modulate defenses in different host types. Intriguingly, while all virus treatments also reduced root production in both host species, only crop-associated BYDV-PAV (or co-infection) reduced rooting depths. Such root effects may increase host susceptibility to drought, and indicate that BYDV-PAV pathogenicity is determined by something other than a P0 VSR. These findings contribute to growing evidence that pathogenic crop-associated viruses may harm native species as well as crops. Critical next questions include the extent to which crop-associated selection pressures drive viral pathogenesis. Copyright © 2017 Elsevier B.V. All rights reserved.

Cerebrospinal fluid lactate: a differential biomarker for bacterial and viral meningitis in children.

Science.gov (United States)

Nazir, Mudasir; Wani, Wasim Ahmad; Malik, Muzaffar Ahmad; Mir, Mohd Rafiq; Ashraf, Younis; Kawoosa, Khalid; Ali, Syed Wajid

To assess the performance of cerebrospinal fluid (CSF) lactate as a biomarker to differentiate bacterial meningitis from viral meningitis in children, and to define an optimal CSF lactate concentration that can be called significant for the differentiation. Children with clinical findings compatible with meningitis were studied. CSF lactate and other conventional CSF parameters were recorded. At a cut-off value of 3mmol/L, CSF lactate had a sensitivity of 0.90, specificity of 1.0, positive predictive value of 1.0, and negative predictive value of 0.963, with an accuracy of 0.972. The positive and negative likelihood ratios were 23.6 and 0.1, respectively. When comparing between bacterial and viral meningitis, the area under the curve for CSF lactate was 0.979. The authors concluded that CSF lactate has high sensitivity and specificity in differentiating bacterial from viral meningitis. While at a cut-off value of 3mmol/L, CSF lactate has high diagnostic accuracy for bacterial meningitis, mean levels in viral meningitis remain essentially below 2mmol/L. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Systems-Biology Approaches to Discover Anti-Viral Effectors of the Human Innate Immune Response

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Andreas F.R. Sommer

2011-07-01

Full Text Available Virus infections elicit an immediate innate response involving antiviral factors. The activities of some of these factors are, in turn, blocked by viral countermeasures. The ensuing battle between the host and the viruses is crucial for determining whether the virus establishes a foothold and/or induces adaptive immune responses. A comprehensive systems-level understanding of the repertoire of anti-viral effectors in the context of these immediate virus-host responses would provide significant advantages in devising novel strategies to interfere with the initial establishment of infections. Recent efforts to identify cellular factors in a comprehensive and unbiased manner, using genome-wide siRNA screens and other systems biology “omics” methodologies, have revealed several potential anti-viral effectors for viruses like Human immunodeficiency virus type 1 (HIV-1, Hepatitis C virus (HCV, West Nile virus (WNV, and influenza virus. This review describes the discovery of novel viral restriction factors and discusses how the integration of different methods in systems biology can be used to more comprehensively identify the intimate interactions of viruses and the cellular innate resistance.

Viral and cellular subnuclear structures in human cytomegalovirus-infected cells.

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Strang, Blair L

2015-02-01

In human cytomegalovirus (HCMV)-infected cells, a dramatic remodelling of the nuclear architecture is linked to the creation, utilization and manipulation of subnuclear structures. This review outlines the involvement of several viral and cellular subnuclear structures in areas of HCMV replication and virus-host interaction that include viral transcription, viral DNA synthesis and the production of DNA-filled viral capsids. The structures discussed include those that promote or impede HCMV replication (such as viral replication compartments and promyelocytic leukaemia nuclear bodies, respectively) and those whose role in the infected cell is unclear (for example, nucleoli and nuclear speckles). Viral and cellular proteins associated with subnuclear structures are also discussed. The data reviewed here highlight advances in our understanding of HCMV biology and emphasize the complexity of HCMV replication and virus-host interactions in the nucleus. © 2015 The Authors.

Sodium-Reduced Meat and Poultry Products Contain a Significant Amount of Potassium from Food Additives.

Science.gov (United States)

Parpia, Arti Sharma; Goldstein, Marc B; Arcand, JoAnne; Cho, France; L'Abbé, Mary R; Darling, Pauline B

2018-05-01

counterparts (mean difference [95% CI]: 486 [334-638]; Padditives appearing on the product label ingredient list, did not significantly differ between the two groups. Potassium additives are frequently added to sodium-reduced MPPs in amounts that significantly contribute to the potassium load for patients with impaired renal handling of potassium caused by chronic kidney disease and certain medications. Patients requiring potassium restriction should be counseled to be cautious regarding the potassium content of sodium-reduced MPPs and encouraged to make food choices accordingly. Copyright © 2018 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Expressions of renin, angiotensin II and aldosterone in patients with viral hepatitis or hepatic cirrhosis

International Nuclear Information System (INIS)

Huo Ying; Zhu Yalin; Liu Yun

2008-01-01

Objective: To explore the changes of renin, angiotensin and aldosterone system in patients with hepatic disorders. Methods: Plasma renin activity (PRA), AT-II and Ald levels were measured with RIA in 31 patients with viral hepatitis, 35 patients with hepatic cirrhosis and 38 controls. Results: The levels of PRA, AT-II and Ald in patients with viral hepatitis were slightly but non-significantly higher than those in controls (P>0.05). The levels of PRA, AT-II and Ald in patients with cirrhosis were significantly higher than those in controls (P<0.01). Conclusion: RAAS was activated during progression of hepatic disorders and participated in the development of hepatic fibrosis. (authors)

Two doses of bovine viral diarrhea virus DNA vaccine delivered by electroporation induce long-term protective immune responses.

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van Drunen Littel-van den Hurk, Sylvia; Lawman, Zoe; Snider, Marlene; Wilson, Don; van den Hurk, Jan V; Ellefsen, Barry; Hannaman, Drew

2013-02-01

Bovine viral diarrhea virus (BVDV) is a pathogen of major importance in cattle, so there is a need for new effective vaccines. DNA vaccines induce balanced immune responses and are relatively inexpensive and thus promising for both human and veterinary applications. In this study, newborn calves with maternal antibodies were vaccinated intramuscularly (i.m.) with a BVDV E2 DNA vaccine with the TriGrid Delivery System for i.m. delivery (TDS-IM). Two doses of this vaccine spaced 6 or 12 weeks apart were sufficient to induce significant virus-neutralizing antibody titers, numbers of activated T cells, and reduction in viral shedding and clinical presentations after BVDV-2 challenge. In contrast to the placebo-treated animals, the vaccinated calves did not lose any weight, which is an excellent indicator of the well-being of an animal and has a significant economic impact. Furthermore, the interval between the two vaccinations did not influence the magnitude of the immune responses or degree of clinical protection, and a third immunization was not necessary or beneficial. Since electroporation may enhance not only the magnitude but also the duration of immunity after DNA immunization, the interval between vaccination and challenge was extended in a second trial, which showed that two doses of this E2 DNA vaccine again significantly reduced clinical disease against BVDV for several months. These results are promising and support this technology for use against infectious diseases in cattle and large species, including humans, in general.

V-GAP: Viral genome assembly pipeline

KAUST Repository

Nakamura, Yoji

2015-10-22

Next-generation sequencing technologies have allowed the rapid determination of the complete genomes of many organisms. Although shotgun sequences from large genome organisms are still difficult to reconstruct perfect contigs each of which represents a full chromosome, those from small genomes have been assembled successfully into a very small number of contigs. In this study, we show that shotgun reads from phage genomes can be reconstructed into a single contig by controlling the number of read sequences used in de novo assembly. We have developed a pipeline to assemble small viral genomes with good reliability using a resampling method from shotgun data. This pipeline, named V-GAP (Viral Genome Assembly Pipeline), will contribute to the rapid genome typing of viruses, which are highly divergent, and thus will meet the increasing need for viral genome comparisons in metagenomic studies.

V-GAP: Viral genome assembly pipeline

KAUST Repository

Nakamura, Yoji; Yasuike, Motoshige; Nishiki, Issei; Iwasaki, Yuki; Fujiwara, Atushi; Kawato, Yasuhiko; Nakai, Toshihiro; Nagai, Satoshi; Kobayashi, Takanori; Gojobori, Takashi; Ototake, Mitsuru

2015-01-01

Next-generation sequencing technologies have allowed the rapid determination of the complete genomes of many organisms. Although shotgun sequences from large genome organisms are still difficult to reconstruct perfect contigs each of which represents a full chromosome, those from small genomes have been assembled successfully into a very small number of contigs. In this study, we show that shotgun reads from phage genomes can be reconstructed into a single contig by controlling the number of read sequences used in de novo assembly. We have developed a pipeline to assemble small viral genomes with good reliability using a resampling method from shotgun data. This pipeline, named V-GAP (Viral Genome Assembly Pipeline), will contribute to the rapid genome typing of viruses, which are highly divergent, and thus will meet the increasing need for viral genome comparisons in metagenomic studies.

The viral envelope is not sufficient to transfer the unique broad cell tropism of Bungowannah virus to a related pestivirus.

Science.gov (United States)

Richter, Maria; Reimann, Ilona; Schirrmeier, Horst; Kirkland, Peter D; Beer, Martin

2014-10-01

Bungowannah virus is the most divergent pestivirus, and both origin and reservoir host have not been identified so far. We therefore performed in vitro tropism studies, which showed that Bungowannah virus differs remarkably from other pestiviruses. Interestingly, cell lines of vervet monkey, mouse, human and even of bat origin were susceptible. This broad in vitro tropism was not observed for a chimeric bovine viral diarrhoea virus (BVDV) expressing all structural proteins of Bungowannah virus. The viral envelope was not sufficient to completely transfer the cell tropism of Bungowannah virus to another pestivirus, and viral RNA replication was either markedly reduced or not detectable in a number of different cell lines for the tested BVDV strain and the chimera. We therefore suggest that the replication machinery together with the viral envelope is responsible for the unique broad cell tropism of Bungowannah virus. © 2014 The Authors.

Eicosanoids and Respiratory Viral Infection: Coordinators of Inflammation and Potential Therapeutic Targets

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Mary K. McCarthy

2012-01-01

Full Text Available Viruses are frequent causes of respiratory infection, and viral respiratory infections are significant causes of hospitalization, morbidity, and sometimes mortality in a variety of patient populations. Lung inflammation induced by infection with common respiratory pathogens such as influenza and respiratory syncytial virus is accompanied by increased lung production of prostaglandins and leukotrienes, lipid mediators with a wide range of effects on host immune function. Deficiency or pharmacologic inhibition of prostaglandin and leukotriene production often results in a dampened inflammatory response to acute infection with a respiratory virus. These mediators may, therefore, serve as appealing therapeutic targets for disease caused by respiratory viral infection.

Viral pathogenesis in diagrams

National Research Council Canada - National Science Library

Tremblay, Michel; Berthiaume, Laurent; Ackermann, Hans-Wolfgang

2001-01-01

.... The 268 diagrams in Viral Pathogenesis in Diagrams were selected from over 800 diagrams of English and French virological literature, including one derived from a famous drawing by Leonardo da Vinci...

Plum Pox Virus 6K1 Protein Is Required for Viral Replication and Targets the Viral Replication Complex at the Early Stage of Infection.

Science.gov (United States)

Cui, Hongguang; Wang, Aiming

2016-05-15

The potyviral RNA genome encodes two polyproteins that are proteolytically processed by three viral protease domains into 11 mature proteins. Extensive molecular studies have identified functions for the majority of the viral proteins. For example, 6K2, one of the two smallest potyviral proteins, is an integral membrane protein and induces the endoplasmic reticulum (ER)-originated replication vesicles that target the chloroplast for robust viral replication. However, the functional role of 6K1, the other smallest protein, remains uncharacterized. In this study, we developed a series of recombinant full-length viral cDNA clones derived from a Canadian Plum pox virus (PPV) isolate. We found that deletion of any of the short motifs of 6K1 (each of which ranged from 5 to 13 amino acids), most of the 6K1 sequence (but with the conserved sequence of the cleavage sites being retained), or all of the 6K1 sequence in the PPV infectious clone abolished viral replication. The trans expression of 6K1 or the cis expression of a dislocated 6K1 failed to rescue the loss-of-replication phenotype, suggesting the temporal and spatial requirement of 6K1 for viral replication. Disruption of the N- or C-terminal cleavage site of 6K1, which prevented the release of 6K1 from the polyprotein, either partially or completely inhibited viral replication, suggesting the functional importance of the mature 6K1. We further found that green fluorescent protein-tagged 6K1 formed punctate inclusions at the viral early infection stage and colocalized with chloroplast-bound viral replicase elements 6K2 and NIb. Taken together, our results suggest that 6K1 is required for viral replication and is an important viral element of the viral replication complex at the early infection stage. Potyviruses account for more than 30% of known plant viruses and consist of many agriculturally important viruses. The genomes of potyviruses encode two polyproteins that are proteolytically processed into 11 mature

Viral infections stimulate the metabolism and shape prokaryotic assemblages in submarine mud volcanoes.

Science.gov (United States)

Corinaldesi, Cinzia; Dell'Anno, Antonio; Danovaro, Roberto

2012-06-01

Mud volcanoes are geological structures in the oceans that have key roles in the functioning of the global ecosystem. Information on the dynamics of benthic viruses and their interactions with prokaryotes in mud volcano ecosystems is still completely lacking. We investigated the impact of viral infection on the mortality and assemblage structure of benthic prokaryotes of five mud volcanoes in the Mediterranean Sea. Mud volcano sediments promote high rates of viral production (1.65-7.89 × 10(9) viruses g(-1) d(-1)), viral-induced prokaryotic mortality (VIPM) (33% cells killed per day) and heterotrophic prokaryotic production (3.0-8.3 μgC g(-1) d(-1)) when compared with sediments outside the mud volcano area. The viral shunt (that is, the microbial biomass converted into dissolved organic matter as a result of viral infection, and thus diverted away from higher trophic levels) provides 49 mgC m(-2) d(-1), thus fuelling the metabolism of uninfected prokaryotes and contributing to the total C budget. Bacteria are the dominant components of prokaryotic assemblages in surface sediments of mud volcanoes, whereas archaea dominate the subsurface sediment layers. Multivariate multiple regression analyses show that prokaryotic assemblage composition is not only dependant on the geochemical features and processes of mud volcano ecosystems but also on synergistic interactions between bottom-up (that is, trophic resources) and top-down (that is, VIPM) controlling factors. Overall, these findings highlight the significant role of the viral shunt in sustaining the metabolism of prokaryotes and shaping their assemblage structure in mud volcano sediments, and they provide new clues for our understanding of the functioning of cold-seep ecosystems.

CRISPR/Cas9-mediated viral interference in plants

KAUST Repository

Ali, Zahir; Abulfaraj, Aala A.; Idris, Ali; Ali, Shawkat; Tashkandi, Manal; Mahfouz, Magdy M.

2015-01-01

These data establish the efficacy of the CRISPR/Cas9 system for viral interference in plants, thereby extending the utility of this technology and opening the possibility of producing plants resistant to multiple viral infections.

Emerging zoonotic viral diseases.

Science.gov (United States)

Wang, L-F; Crameri, G

2014-08-01

Zoonotic diseases are infectious diseases that are naturally transmitted from vertebrate animals to humans and vice versa. They are caused by all types of pathogenic agents, including bacteria, parasites, fungi, viruses and prions. Although they have been recognised for many centuries, their impact on public health has increased in the last few decades due to a combination of the success in reducing the spread of human infectious diseases through vaccination and effective therapies and the emergence of novel zoonotic diseases. It is being increasingly recognised that a One Health approach at the human-animal-ecosystem interface is needed for effective investigation, prevention and control of any emerging zoonotic disease. Here, the authors will review the drivers for emergence, highlight some of the high-impact emerging zoonotic diseases of the last two decades and provide examples of novel One Health approaches for disease investigation, prevention and control. Although this review focuses on emerging zoonotic viral diseases, the authors consider that the discussions presented in this paper will be equally applicable to emerging zoonotic diseases of other pathogen types.

Contribution of herpesvirus specific CD8 T cells to anti-viral T cell response in humans.

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Elena Sandalova

Full Text Available Herpesviruses infect most humans. Their infections can be associated with pathological conditions and significant changes in T cell repertoire but evidences of symbiotic effects of herpesvirus latency have never been demonstrated. We tested the hypothesis that HCMV and EBV-specific CD8 T cells contribute to the heterologous anti-viral immune response. Volume of activated/proliferating virus-specific and total CD8 T cells was evaluated in 50 patients with acute viral infections: 20 with HBV, 12 with Dengue, 12 with Influenza, 3 with Adenovirus infection and 3 with fevers of unknown etiology. Virus-specific (EBV, HCMV, Influenza pentamer+ and total CD8 T cells were analyzed for activation (CD38/HLA-DR, proliferation (Ki-67/Bcl-2(low and cytokine production. We observed that all acute viral infections trigger an expansion of activated/proliferating CD8 T cells, which differs in size depending on the infection but is invariably inflated by CD8 T cells specific for persistent herpesviruses (HCMV/EBV. CD8 T cells specific for other non-related non persistent viral infection (i.e. Influenza were not activated. IL-15, which is produced during acute viral infections, is the likely contributing mechanism driving the selective activation of herpesvirus specific CD8 T cells. In addition we were able to show that herpesvirus specific CD8 T cells displayed an increased ability to produce the anti-viral cytokine interferon-gamma during the acute phase of heterologous viral infection. Taken together, these data demonstrated that activated herpesvirus specific CD8 T cells inflate the activated/proliferating CD8 T cells population present during acute viral infections in human and can contribute to the heterologous anti-viral T cell response.

Efficacy of Chistonos for Children in the Treatment and Prevention of Acute Respiratory Viral Infections in Preschool Children

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I.V. Dahaieva

2016-02-01

Full Text Available The complex of treatment of acute respiratory viral infection (ARVI, acute rhinitis in 43 preschool children was supplemented by endonasal irrigations of Chistonos for children, which is a dosing gel spray containing sea salt, β-carotene, aloe and calendula extracts. A marked local symptomatic relief was registered, as well as an acceleration of the regression of inflammatory changes in the nasal cavity and a significant decrease in the number of complications after acute respiratory disease. Prophylactic use of the product in the preseason allowed to decrease the ARVI (including influenza morbidity rate and to reduce the incidence of the severe form of the disease.

VirSorter: mining viral signal from microbial genomic data

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Simon Roux

2015-05-01

Full Text Available Viruses of microbes impact all ecosystems where microbes drive key energy and substrate transformations including the oceans, humans and industrial fermenters. However, despite this recognized importance, our understanding of viral diversity and impacts remains limited by too few model systems and reference genomes. One way to fill these gaps in our knowledge of viral diversity is through the detection of viral signal in microbial genomic data. While multiple approaches have been developed and applied for the detection of prophages (viral genomes integrated in a microbial genome, new types of microbial genomic data are emerging that are more fragmented and larger scale, such as Single-cell Amplified Genomes (SAGs of uncultivated organisms or genomic fragments assembled from metagenomic sequencing. Here, we present VirSorter, a tool designed to detect viral signal in these different types of microbial sequence data in both a reference-dependent and reference-independent manner, leveraging probabilistic models and extensive virome data to maximize detection of novel viruses. Performance testing shows that VirSorter’s prophage prediction capability compares to that of available prophage predictors for complete genomes, but is superior in predicting viral sequences outside of a host genome (i.e., from extrachromosomal prophages, lytic infections, or partially assembled prophages. Furthermore, VirSorter outperforms existing tools for fragmented genomic and metagenomic datasets, and can identify viral signal in assembled sequence (contigs as short as 3kb, while providing near-perfect identification (>95% Recall and 100% Precision on contigs of at least 10kb. Because VirSorter scales to large datasets, it can also be used in “reverse” to more confidently identify viral sequence in viral metagenomes by sorting away cellular DNA whether derived from gene transfer agents, generalized transduction or contamination. Finally, VirSorter is made

VirSorter: mining viral signal from microbial genomic data

Science.gov (United States)

Roux, Simon; Enault, Francois; Hurwitz, Bonnie L.

2015-01-01

Viruses of microbes impact all ecosystems where microbes drive key energy and substrate transformations including the oceans, humans and industrial fermenters. However, despite this recognized importance, our understanding of viral diversity and impacts remains limited by too few model systems and reference genomes. One way to fill these gaps in our knowledge of viral diversity is through the detection of viral signal in microbial genomic data. While multiple approaches have been developed and applied for the detection of prophages (viral genomes integrated in a microbial genome), new types of microbial genomic data are emerging that are more fragmented and larger scale, such as Single-cell Amplified Genomes (SAGs) of uncultivated organisms or genomic fragments assembled from metagenomic sequencing. Here, we present VirSorter, a tool designed to detect viral signal in these different types of microbial sequence data in both a reference-dependent and reference-independent manner, leveraging probabilistic models and extensive virome data to maximize detection of novel viruses. Performance testing shows that VirSorter’s prophage prediction capability compares to that of available prophage predictors for complete genomes, but is superior in predicting viral sequences outside of a host genome (i.e., from extrachromosomal prophages, lytic infections, or partially assembled prophages). Furthermore, VirSorter outperforms existing tools for fragmented genomic and metagenomic datasets, and can identify viral signal in assembled sequence (contigs) as short as 3kb, while providing near-perfect identification (>95% Recall and 100% Precision) on contigs of at least 10kb. Because VirSorter scales to large datasets, it can also be used in “reverse” to more confidently identify viral sequence in viral metagenomes by sorting away cellular DNA whether derived from gene transfer agents, generalized transduction or contamination. Finally, VirSorter is made available through the i

TMV-Cg Coat Protein stabilizes DELLA proteins and in turn negatively modulates salicylic acid-mediated defense pathway during Arabidopsis thaliana viral infection.

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Rodriguez, Maria Cecilia; Conti, Gabriela; Zavallo, Diego; Manacorda, Carlos Augusto; Asurmendi, Sebastian

2014-08-03

Plant viral infections disturb defense regulatory networks during tissue invasion. Emerging evidence demonstrates that a significant proportion of these alterations are mediated by hormone imbalances. Although the DELLA proteins have been reported to be central players in hormone cross-talk, their role in the modulation of hormone signaling during virus infections remains unknown. This work revealed that TMV-Cg coat protein (CgCP) suppresses the salicylic acid (SA) signaling pathway without altering defense hormone SA or jasmonic acid (JA) levels in Arabidopsis thaliana. Furthermore, it was observed that the expression of CgCP reduces plant growth and delays the timing of floral transition. Quantitative RT-qPCR analysis of DELLA target genes showed that CgCP alters relative expression of several target genes, indicating that the DELLA proteins mediate transcriptional changes produced by CgCP expression. Analyses by fluorescence confocal microscopy showed that CgCP stabilizes DELLA proteins accumulation in the presence of gibberellic acid (GA) and that the DELLA proteins are also stabilized during TMV-Cg virus infections. Moreover, DELLA proteins negatively modulated defense transcript profiles during TMV-Cg infection. As a result, TMV-Cg accumulation was significantly reduced in the quadruple-DELLA mutant Arabidopsis plants compared to wild type plants. Taken together, these results demonstrate that CgCP negatively regulates the salicylic acid-mediated defense pathway by stabilizing the DELLA proteins during Arabidopsis thaliana viral infection, suggesting that CgCP alters the stability of DELLAs as a mechanism of negative modulation of antiviral defense responses.

The Ins and Outs of Viral Infection: Keystone Meeting Review

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Sara W. Bird

2014-09-01

Full Text Available Newly observed mechanisms for viral entry, assembly, and exit are challenging our current understanding of the replication cycle of different viruses. To address and better understand these mechanisms, a Keystone Symposium was organized in the snowy mountains of Colorado (“The Ins and Outs of Viral Infection: Entry, Assembly, Exit, and Spread”; 30 March–4 April 2014, Beaver Run Resort, Breckenridge, Colorado, organized by Karla Kirkegaard, Mavis Agbandje-McKenna, and Eric O. Freed. The meeting served to bring together cell biologists, structural biologists, geneticists, and scientists expert in viral pathogenesis to discuss emerging mechanisms of viral ins and outs. The conference was organized around different phases of the viral replication cycle, including cell entry, viral assembly and post-assembly maturation, virus structure, cell exit, and virus spread. This review aims to highlight important topics and themes that emerged during the conference.

Altered oral viral ecology in association with periodontal disease.

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Ly, Melissa; Abeles, Shira R; Boehm, Tobias K; Robles-Sikisaka, Refugio; Naidu, Mayuri; Santiago-Rodriguez, Tasha; Pride, David T

2014-05-20

The human oral cavity is home to a large and diverse community of viruses that have yet to be characterized in patients with periodontal disease. We recruited and sampled saliva and oral biofilm from a cohort of humans either periodontally healthy or with mild or significant periodontal disease to discern whether there are differences in viral communities that reflect their oral health status. We found communities of viruses inhabiting saliva and the subgingival and supragingival biofilms of each subject that were composed largely of bacteriophage. While there were homologous viruses common to different subjects and biogeographic sites, for most of the subjects, virome compositions were significantly associated with the oral sites from which they were derived. The largest distinctions between virome compositions were found when comparing the subgingival and supragingival biofilms to those of planktonic saliva. Differences in virome composition were significantly associated with oral health status for both subgingival and supragingival biofilm viruses but not for salivary viruses. Among the differences identified in virome compositions was a significant expansion of myoviruses in subgingival biofilm, suggesting that periodontal disease favors lytic phage. We also characterized the bacterial communities in each subject at each biogeographic site by using the V3 hypervariable segment of the 16S rRNA and did not identify distinctions between oral health and disease similar to those found in viral communities. The significantly altered ecology of viruses of oral biofilm in subjects with periodontal disease compared to that of relatively periodontally healthy ones suggests that viruses may serve as useful indicators of oral health status. Little is known about the role or the constituents of viruses as members of the human microbiome. We investigated the composition of human oral viral communities in a group of relatively periodontally healthy subjects or significant

Interferon therapy of acute respiratory viral infections in children

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A.E. Abaturov

2017-04-01

Full Text Available The purpose of our study was to evaluate the efficacy and tolerability of nasal spray Laferobionum® (100,000 IU/ml in children with acute respiratory viral infections. Materials and methods. The study included 84 children aged 12 to 18 years. Children of the main group (42 persons received Laferobionum® spray in addition to the standard treatment for acute respiratory viral infections. The drug was administered to children of 12–14 years for 2 spray doses in each nasal passage 4–5 times a day at regular intervals (with the exception of sleep time, children aged 14–18 years received 3 spray-doses per each nasal passage 5–6 times a day at regular intervals (excluding sleep time. The course of treatment for all subjects was 5 days. Children of the control group received standard treatment for acute respiratory viral infections without Laferobionum®. Objective research included: auscultation of the heart and lungs, examination of the skin and mucous membranes, measurement of heart rate, blood pressure and body temperature. All patients underwent a general blood test, a general urinalysis, identification of the pathogen using the method of direct immunofluorescence (in smears taken from the nasal passages in the laboratory “Medical Diagnostic Center of Dnipropetrovsk Medical Academy”. Results. In the non-epidemic period, the respiratory syncytial virus and adenoviruses were the leading viral pathogens of acute respiratory viral infections. The main clinical manifestations of acute respiratory viral infection in the observed patients were signs of general inflammatory and catarrhal syndromes. All patients had not severe course of the disease. The data of the physical examination performed before the beginning of treatment indicated the absence of clinically significant deviations from the cardiovascular system in the children of the main and control groups. Arterial blood pressure and heart rate in the subjects of both groups were

Viral tropism and pathology associated with viral hemorrhagic septicemia in larval and juvenile Pacific herring

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Lovy, Jan; Lewis, N.L.; Hershberger, P.K.; Bennett, W.; Meyers, T.R.; Garver, K.A.

2012-01-01

Viral hemorrhagic septicemia virus (VHSV) genotype IVa causes mass mortality in wild Pacific herring, a species of economic value, in the Northeast Pacific Ocean. Young of the year herring are particularly susceptible and can be carriers of the virus. To understand its pathogenesis, tissue and cellular tropisms of VHSV in larval and juvenile Pacific herring were investigated with immunohistochemistry, transmission electron microscopy, and viral tissue titer. In larval herring, early viral tropism for epithelial tissues (6d post-exposure) was indicated by foci of epidermal thickening that contained heavy concentrations of virus. This was followed by a cellular tropism for fibroblasts within the fin bases and the dermis, but expanded to cells of the kidney, liver, pancreas, gastrointestinal tract and meninges in the brain. Among wild juvenile herring that underwent a VHS epizootic in the laboratory, the disease was characterized by acute and chronic phases of death. Fish that died during the acute phase had systemic infections in tissues including the submucosa of the gastrointestinal tract, spleen, kidney, liver, and meninges. The disease then transitioned into a chronic phase that was characterized by the appearance of neurological signs including erratic and corkscrew swimming and darkening of the dorsal skin. During the chronic phase viral persistence occurred in nervous tissues including meninges and brain parenchymal cells and in one case in peripheral nerves, while virus was mostly cleared from the other tissues. The results demonstrate the varying VHSV tropisms dependent on the timing of infection and the importance of neural tissues for the persistence and perpetuation of chronic infections in Pacific herring.

Analysis of the viral progeny during the indirect recombinogenesis of the lambda bacteriophage

International Nuclear Information System (INIS)

Alcantara D, D.

1993-12-01

In this work the effect of the UV irradiation on the number of cells that follow the lytic via of the phage is determined, as well as the production of total particles and recombinants in irradiated individual cells and not irradiated with light UV. The results show that the indirect recombinogenesis of lambda is caused by a so much increment in the number of recombinant phages for cells like in the number of cells in those that happen events of viral recombination, without any significant effect on the number of bacteria that follow the lytic via of viral development. (Author)

A viral microRNA functions as an ortholog of cellular miR-155

Science.gov (United States)

Gottwein, Eva; Mukherjee, Neelanjan; Sachse, Christoph; Frenzel, Corina; Majoros, William H.; Chi, Jen-Tsan A.; Braich, Ravi; Manoharan, Muthiah; Soutschek, Jürgen; Ohler, Uwe; Cullen, Bryan R.

2008-01-01

All metazoan eukaryotes express microRNAs (miRNAs), ∼22 nt regulatory RNAs that can repress the expression of mRNAs bearing complementary sequences1. Several DNA viruses also express miRNAs in infected cells, suggesting a role in viral replication and pathogenesis2. While specific viral miRNAs have been shown to autoregulate viral mRNAs3,4 or downregulate cellular mRNAs5,6, the function of the majority of viral miRNAs remains unknown. Here, we report that the miR-K12−11 miRNA encoded by Kaposi's Sarcoma Associated Herpesvirus (KSHV) shows significant homology to cellular miR-155, including the entire miRNA “seed” region7. Using a range of assays, we demonstrate that expression of physiological levels of miR-K12−11 or miR-155 results in the downregulation of an extensive set of common mRNA targets, including genes with known roles in cell growth regulation. Our findings indicate that viral miR-K12−11 functions as an ortholog of cellular miR-155 and has likely evolved to exploit a pre-existing gene regulatory pathway in B-cells. Moreover, the known etiological role of miR-155 in B-cell transformation8-10 suggests that miR-K12−11 may contribute to the induction of KSHV-positive B-cell tumors in infected patients. PMID:18075594

Viral infection and antiviral therapy in the neonatal intensive care unit.

Science.gov (United States)

Barford, Galina; Rentz, Alison C; Faix, Roger G

2004-01-01

Viral diseases are leading causes of mortality and morbidity among infants requiring care in the neonatal intensive care unit (NICU), with ongoing discoveries of new viral pathology likely to add to the burdens posed. Many viral diseases in NICU infants are undiagnosed or appreciated only late in the course because of subtle or asymptomatic presentation, confusion with bacterial disease, and failure to consider viral disease. We present an overview of viral disease in NICU infants, with emphasis on pharmacologic agents currently employed for prophylaxis and treatment of such diseases. Advances in molecular biology and popular demand to develop antiviral agents for viral diseases (eg, human immunodeficiency virus) offer great promise for the future.

A chimpanzee recognizes synthetic speech with significantly reduced acoustic cues to phonetic content.

Science.gov (United States)

Heimbauer, Lisa A; Beran, Michael J; Owren, Michael J

2011-07-26

A long-standing debate concerns whether humans are specialized for speech perception, which some researchers argue is demonstrated by the ability to understand synthetic speech with significantly reduced acoustic cues to phonetic content. We tested a chimpanzee (Pan troglodytes) that recognizes 128 spoken words, asking whether she could understand such speech. Three experiments presented 48 individual words, with the animal selecting a corresponding visuographic symbol from among four alternatives. Experiment 1 tested spectrally reduced, noise-vocoded (NV) synthesis, originally developed to simulate input received by human cochlear-implant users. Experiment 2 tested "impossibly unspeechlike" sine-wave (SW) synthesis, which reduces speech to just three moving tones. Although receiving only intermittent and noncontingent reward, the chimpanzee performed well above chance level, including when hearing synthetic versions for the first time. Recognition of SW words was least accurate but improved in experiment 3 when natural words in the same session were rewarded. The chimpanzee was more accurate with NV than SW versions, as were 32 human participants hearing these items. The chimpanzee's ability to spontaneously recognize acoustically reduced synthetic words suggests that experience rather than specialization is critical for speech-perception capabilities that some have suggested are uniquely human. Copyright © 2011 Elsevier Ltd. All rights reserved.

Novel viral genomes identified from six metagenomes reveal wide distribution of archaeal viruses and high viral diversity in terrestrial hot springs

DEFF Research Database (Denmark)

Islin, Sóley Ruth; Menzel, Peter; Krogh, Anders

2016-01-01

Limited by culture-dependent methods the number of viruses identified from thermophilic Archaea and Bacteria is still very small. In this study we retrieved viral sequences from six hot spring metagenomes isolated worldwide, revealing a wide distribution of four archaeal viral families....... Among the novel genomes, one belongs to a putative thermophilic virus infecting the bacterium Hydrogenobaculum, for which no virus has been reported in the literature. Moreover, a high viral diversity was observed in the metagenomes, especially among the Lipothrixviridae, as indicated by the large...

Improving laboratory efficiencies to scale-up HIV viral load testing.

Science.gov (United States)

Alemnji, George; Onyebujoh, Philip; Nkengasong, John N

2017-03-01

Viral load measurement is a key indicator that determines patients' response to treatment and risk for disease progression. Efforts are ongoing in different countries to scale-up access to viral load testing to meet the Joint United Nations Programme on HIV and AIDS target of achieving 90% viral suppression among HIV-infected patients receiving antiretroviral therapy. However, the impact of these initiatives may be challenged by increased inefficiencies along the viral load testing spectrum. This will translate to increased costs and ineffectiveness of scale-up approaches. This review describes different parameters that could be addressed across the viral load testing spectrum aimed at improving efficiencies and utilizing test results for patient management. Though progress is being made in some countries to scale-up viral load, many others still face numerous challenges that may affect scale-up efficiencies: weak demand creation, ineffective supply chain management systems; poor specimen referral systems; inadequate data and quality management systems; and weak laboratory-clinical interface leading to diminished uptake of test results. In scaling up access to viral load testing, there should be a renewed focus to address efficiencies across the entire spectrum, including factors related to access, uptake, and impact of test results.

Intensity-modulated radiotherapy significantly reduces xerostomia compared with conventional radiotherapy

International Nuclear Information System (INIS)

Braam, Petra M.; Terhaard, Chris H.J. M.D.; Roesink, Judith M.; Raaijmakers, Cornelis P.J.

2006-01-01

Purpose: Xerostomia is a severe complication after radiotherapy for oropharyngeal cancer, as the salivary glands are in close proximity with the primary tumor. Intensity-modulated radiotherapy (IMRT) offers theoretical advantages for normal tissue sparing. A Phase II study was conducted to determine the value of IMRT for salivary output preservation compared with conventional radiotherapy (CRT). Methods and Materials: A total of 56 patients with oropharyngeal cancer were prospectively evaluated. Of these, 30 patients were treated with IMRT and 26 with CRT. Stimulated parotid salivary flow was measured before, 6 weeks, and 6 months after treatment. A complication was defined as a stimulated parotid flow rate <25% of the preradiotherapy flow rate. Results: The mean dose to the parotid glands was 48.1 Gy (SD 14 Gy) for CRT and 33.7 Gy (SD 10 Gy) for IMRT (p < 0.005). The mean parotid flow ratio 6 weeks and 6 months after treatment was respectively 41% and 64% for IMRT and respectively 11% and 18% for CRT. As a result, 6 weeks after treatment, the number of parotid flow complications was significantly lower after IMRT (55%) than after CRT (87%) (p = 0.002). The number of complications 6 months after treatment was 56% for IMRT and 81% for CRT (p = 0.04). Conclusions: IMRT significantly reduces the number of parotid flow complications for patients with oropharyngeal cancer

FastStats: Viral Hepatitis

Science.gov (United States)

... Submit What's this? Submit Button NCHS Home Viral Hepatitis Recommend on Facebook Tweet Share Compartir Data are for the U.S. Morbidity Number of new hepatitis A cases: 1,239 (2014) Number of new ...

454-Pyrosequencing: A Molecular Battiscope for Freshwater Viral Ecology

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David J. Rooks

2010-07-01

Full Text Available Viruses, the most abundant biological entities on the planet, are capable of infecting organisms from all three branches of life, although the majority infect bacteria where the greatest degree of cellular diversity lies. However, the characterization and assessment of viral diversity in natural environments is only beginning to become a possibility. Through the development of a novel technique for the harvest of viral DNA and the application of 454 pyrosequencing, a snapshot of the diversity of the DNA viruses harvested from a standing pond on a cattle farm has been obtained. A high abundance of viral genotypes (785 were present within the virome. The absolute numbers of lambdoid and Shiga toxin (Stx encoding phages detected suggested that the depth of sequencing had enabled recovery of only ca. 8% of the total virus population, numbers that agreed within less than an order of magnitude with predictions made by rarefaction analysis. The most abundant viral genotypes in the pond were bacteriophages (93.7%. The predominant viral genotypes infecting higher life forms found in association with the farm were pathogens that cause disease in cattle and humans, e.g. members of the Herpesviridae. The techniques and analysis described here provide a fresh approach to the monitoring of viral populations in the aquatic environment, with the potential to become integral to the development of risk analysis tools for monitoring the dissemination of viral agents of animal, plant and human diseases.

Parallel epigenomic and transcriptomic responses to viral infection in honey bees (Apis mellifera).

Science.gov (United States)

Galbraith, David A; Yang, Xingyu; Niño, Elina Lastro; Yi, Soojin; Grozinger, Christina

2015-03-01

Populations of honey bees are declining throughout the world, with US beekeepers losing 30% of their colonies each winter. Though multiple factors are driving these colony losses, it is increasingly clear that viruses play a major role. However, information about the molecular mechanisms mediating antiviral immunity in honey bees is surprisingly limited. Here, we examined the transcriptional and epigenetic (DNA methylation) responses to viral infection in honey bee workers. One-day old worker honey bees were fed solutions containing Israeli Acute Paralysis Virus (IAPV), a virus which causes muscle paralysis and death and has previously been associated with colony loss. Uninfected control and infected, symptomatic bees were collected within 20-24 hours after infection. Worker fat bodies, the primary tissue involved in metabolism, detoxification and immune responses, were collected for analysis. We performed transcriptome- and bisulfite-sequencing of the worker fat bodies to identify genome-wide gene expression and DNA methylation patterns associated with viral infection. There were 753 differentially expressed genes (FDR<0.05) in infected versus control bees, including several genes involved in epigenetic and antiviral pathways. DNA methylation status of 156 genes (FDR<0.1) changed significantly as a result of the infection, including those involved in antiviral responses in humans. There was no significant overlap between the significantly differentially expressed and significantly differentially methylated genes, and indeed, the genomic characteristics of these sets of genes were quite distinct. Our results indicate that honey bees have two distinct molecular pathways, mediated by transcription and methylation, that modulate protein levels and/or function in response to viral infections.

Parallel epigenomic and transcriptomic responses to viral infection in honey bees (Apis mellifera.

Directory of Open Access Journals (Sweden)

David A Galbraith

2015-03-01

Full Text Available Populations of honey bees are declining throughout the world, with US beekeepers losing 30% of their colonies each winter. Though multiple factors are driving these colony losses, it is increasingly clear that viruses play a major role. However, information about the molecular mechanisms mediating antiviral immunity in honey bees is surprisingly limited. Here, we examined the transcriptional and epigenetic (DNA methylation responses to viral infection in honey bee workers. One-day old worker honey bees were fed solutions containing Israeli Acute Paralysis Virus (IAPV, a virus which causes muscle paralysis and death and has previously been associated with colony loss. Uninfected control and infected, symptomatic bees were collected within 20-24 hours after infection. Worker fat bodies, the primary tissue involved in metabolism, detoxification and immune responses, were collected for analysis. We performed transcriptome- and bisulfite-sequencing of the worker fat bodies to identify genome-wide gene expression and DNA methylation patterns associated with viral infection. There were 753 differentially expressed genes (FDR<0.05 in infected versus control bees, including several genes involved in epigenetic and antiviral pathways. DNA methylation status of 156 genes (FDR<0.1 changed significantly as a result of the infection, including those involved in antiviral responses in humans. There was no significant overlap between the significantly differentially expressed and significantly differentially methylated genes, and indeed, the genomic characteristics of these sets of genes were quite distinct. Our results indicate that honey bees have two distinct molecular pathways, mediated by transcription and methylation, that modulate protein levels and/or function in response to viral infections.

The stress granule component TIA-1 binds tick-borne encephalitis virus RNA and is recruited to perinuclear sites of viral replication to inhibit viral translation.

Science.gov (United States)

Albornoz, Amelina; Carletti, Tea; Corazza, Gianmarco; Marcello, Alessandro

2014-06-01

Flaviviruses are a major cause of disease in humans and animals worldwide. Tick-borne encephalitis virus (TBEV) is the most important arthropod-borne flavivirus endemic in Europe and is the etiological agent of tick-borne encephalitis, a potentially fatal infection of the central nervous system. However, the contributions of host proteins during TBEV infection are poorly understood. In this work, we investigate the cellular protein TIA-1 and its cognate factor TIAR, which are stress-induced RNA-binding proteins involved in the repression of initiation of translation of cellular mRNAs and in the formation of stress granules. We show that TIA-1 and TIAR interact with viral RNA in TBEV-infected cells. During TBEV infection, cytoplasmic TIA-1 and TIAR are recruited at sites of viral replication with concomitant depletion from stress granules. This effect is specific, since G3BP1, another component of these cytoplasmic structures, remains localized to stress granules. Moreover, heat shock induction of stress granules containing TIA-1, but not G3BP1, is inhibited in TBEV-infected cells. Infection of cells depleted of TIA-1 or TIAR by small interfering RNA (siRNA) or TIA-1(-/-) mouse fibroblasts, leads to a significant increase in TBEV extracellular infectivity. Interestingly, TIAR(-/-) fibroblasts show the opposite effect on TBEV infection, and this phenotype appears to be related to an excess of TIA-1 in these cells. Taking advantage of a TBE-luciferase replicon system, we also observed increased luciferase activity in TIA-1(-/-) mouse fibroblasts at early time points, consistent with TIA-1-mediated inhibition at the level of the first round of viral translation. These results indicate that, in response to TBEV infection, TIA-1 is recruited to sites of virus replication to bind TBEV RNA and modulate viral translation independently of stress granule (SG) formation. This study (i) extends previous work that showed TIA-1/TIAR recruitment at sites of flavivirus replication

Human T-cell leukemia virus type 2 post-transcriptional control protein p28 is required for viral infectivity and persistence in vivo.

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Yamamoto, Brenda; Li, Min; Kesic, Matthew; Younis, Ihab; Lairmore, Michael D; Green, Patrick L

2008-05-12

Human T-cell leukemia virus (HTLV) type 1 and type 2 are related but distinct pathogenic complex retroviruses. HTLV-1 is associated with adult T-cell leukemia and a variety of immune-mediated disorders including the chronic neurological disease termed HTLV-1-associated myelopathy/tropical spastic paraparesis. In contrast, HTLV-2 displays distinct biological differences and is much less pathogenic, with only a few reported cases of leukemia and neurological disease associated with infection. In addition to the structural and enzymatic proteins, HTLV encodes regulatory (Tax and Rex) and accessory proteins. Tax and Rex positively regulate virus production and are critical for efficient viral replication and pathogenesis. Using an over-expression system approach, we recently reported that the accessory gene product of the HTLV-1 and HTLV-2 open reading frame (ORF) II (p30 and p28, respectively) acts as a negative regulator of both Tax and Rex by binding to and retaining their mRNA in the nucleus, leading to reduced protein expression and virion production. Further characterization revealed that p28 was distinct from p30 in that it was devoid of major transcriptional modulating activity, suggesting potentially divergent functions that may be responsible for the distinct pathobiologies of HTLV-1 and HTLV-2. In this study, we investigated the functional significance of p28 in HTLV-2 infection, proliferation, and immortaliztion of primary T-cells in culture, and viral survival in an infectious rabbit animal model. An HTLV-2 p28 knockout virus (HTLV-2Deltap28) was generated and evaluated. Infectivity and immortalization capacity of HTLV-2Deltap28 in vitro was indistinguishable from wild type HTLV-2. In contrast, we showed that viral replication was severely attenuated in rabbits inoculated with HTLV-2Deltap28 and the mutant virus failed to establish persistent infection. We provide direct evidence that p28 is dispensable for viral replication and cellular immortalization of

Community-driven demand creation for the use of routine viral load testing: a model to scale up routine viral load testing.

Science.gov (United States)

Killingo, Bactrin M; Taro, Trisa B; Mosime, Wame N

2017-11-01

HIV treatment outcomes are dependent on the use of viral load measurement. Despite global and national guidelines recommending the use of routine viral load testing, these policies alone have not translated into widespread implementation or sufficiently increased access for people living with HIV (PLHIV). Civil society and communities of PLHIV recognize the need to close this gap and to enable the scale up of routine viral load testing. The International Treatment Preparedness Coalition (ITPC) developed an approach to community-led demand creation for the use of routine viral load testing. Using this Community Demand Creation Model, implementers follow a step-wise process to capacitate and empower communities to address their most pressing needs. This includes utlizing a specific toolkit that includes conducting a baseline assessment, developing a treatment education toolkit, organizing mobilization workshops for knowledge building, provision of small grants to support advocacy work and conducting benchmark evaluations. The Community Demand Creation Model to increase demand for routine viral load testing services by PLHIV has been delivered in diverse contexts including in the sub-Saharan African, Asian, Latin American and the Caribbean regions. Between December 2015 and December 2016, ITPC trained more than 240 PLHIV activists, and disbursed US$90,000 to network partners in support of their national advocacy work. The latter efforts informed a regional, community-driven campaign calling for domestic investment in the expeditious implementation of national viral load testing guidelines. HIV treatment education and community mobilization are critical components of demand creation for access to optimal HIV treatment, especially for the use of routine viral load testing. ITPC's Community Demand Creation Model offers a novel approach to achieving this goal. © 2017 The Authors. Journal of the International AIDS Society published by John Wiley & sons Ltd on behalf of

HPV integration hijacks and multimerizes a cellular enhancer to generate a viral-cellular super-enhancer that drives high viral oncogene expression

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Redmond, Catherine J.; Dooley, Katharine E.; Fu, Haiqing; Gillison, Maura L.; Akagi, Keiko; Symer, David E.; Aladjem, Mirit I.

2018-01-01

Integration of human papillomavirus (HPV) genomes into cellular chromatin is common in HPV-associated cancers. Integration is random, and each site is unique depending on how and where the virus integrates. We recently showed that tandemly integrated HPV16 could result in the formation of a super-enhancer-like element that drives transcription of the viral oncogenes. Here, we characterize the chromatin landscape and genomic architecture of this integration locus to elucidate the mechanisms that promoted de novo super-enhancer formation. Using next-generation sequencing and molecular combing/fiber-FISH, we show that ~26 copies of HPV16 are integrated into an intergenic region of chromosome 2p23.2, interspersed with 25 kb of amplified, flanking cellular DNA. This interspersed, co-amplified viral-host pattern is frequent in HPV-associated cancers and here we designate it as Type III integration. An abundant viral-cellular fusion transcript encoding the viral E6/E7 oncogenes is expressed from the integration locus and the chromatin encompassing both the viral enhancer and a region in the adjacent amplified cellular sequences is strongly enriched in the super-enhancer markers H3K27ac and Brd4. Notably, the peak in the amplified cellular sequence corresponds to an epithelial-cell-type specific enhancer. Thus, HPV16 integration generated a super-enhancer-like element composed of tandem interspersed copies of the viral upstream regulatory region and a cellular enhancer, to drive high levels of oncogene expression. PMID:29364907

Frequency of viral etiology in symptomatic adult upper respiratory tract infections

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Raquel Cirlene da Silva

2015-01-01

Conclusion: Results presented in this report suggest that respiratory viral infections are largely under diagnosed in immunocompetent adults. Although the majority of young adult infections are not life-threatening they may impose a significant burden, especially in developing countries since these individuals represent a large fraction of the working force.

Symptomatic and asymptomatic respiratory viral infections in the first year of life: association with acute otitis media development.

Science.gov (United States)

Chonmaitree, Tasnee; Alvarez-Fernandez, Pedro; Jennings, Kristofer; Trujillo, Rocio; Marom, Tal; Loeffelholz, Michael J; Miller, Aaron L; McCormick, David P; Patel, Janak A; Pyles, Richard B

2015-01-01

Sensitive diagnostic assays have increased the detection of viruses in asymptomatic individuals. The clinical significance of asymptomatic respiratory viral infection in infants is unknown. High-throughput, quantitative polymerase chain reaction assays were used to detect 13 common respiratory viruses from nasopharyngeal specimens collected during 2028 visits from 362 infants followed from near birth up to 12 months of age. Specimens were collected at monthly interval (months 1-6 and month 9) and during upper respiratory tract infection (URTI) episodes. Subjects were followed closely for acute otitis media (AOM) development. Viruses were detected in 76% of 394 URTI specimens and 27% of asymptomatic monthly specimens. Rhinovirus was detected most often; multiple viruses were detected in 29% of the specimens. Generalized mixed-model analyses associated symptoms with increasing age and female sex; detection of respiratory syncytial virus (RSV), influenza, rhinovirus, metapneumovirus, and adenovirus was highly associated with symptoms. Increasing age was also associated with multiple virus detection. Overall, 403 asymptomatic viral infections in 237 infants were identified. Viral load was significantly higher in URTI specimens than asymptomatic specimens but did not differentiate cases of URTI with and without AOM complication. The rate of AOM complicating URTI was 27%; no AOM occurred following asymptomatic viral infections. AOM development was associated with increasing age and infection with RSV, rhinovirus, enterovirus, adenovirus, and bocavirus. Compared to symptomatic infection, asymptomatic viral infection in infants is associated with young age, male sex, low viral load, specific viruses, and single virus detection. Asymptomatic viral infection did not result in AOM. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Junk DNA enhances pEI-based non-viral gene delivery

NARCIS (Netherlands)

Gaal, E.V.B. van; Oosting, R.S.; Hennink, W.E.; Crommelin, D.J.A.; Mastrobattista, E.

Gene therapy aims at delivering exogenous DNA into the nuclei of target cells to establish expression of a therapeutic protein. Non-viral gene delivery is examined as a safer alternative to viral approaches, but is presently characterized by a low efficiency. In the past years several non-viral

Influenza A Virus Hemagglutinin is Required for the Assembly of Viral Components Including Bundled vRNPs at the Lipid Raft

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Naoki Takizawa

2016-09-01

Full Text Available The influenza glycoproteins, hemagglutinin (HA and neuraminidase (NA, which are associated with the lipid raft, have the potential to initiate virion budding. However, the role of these viral proteins in infectious virion assembly is still unclear. In addition, it is not known how the viral ribonucleoprotein complex (vRNP is tethered to the budding site. Here, we show that HA is necessary for the efficient progeny virion production and vRNP packaging in the virion. We also found that the level of HA does not affect the bundling of the eight vRNP segments, despite reduced virion production. Detergent solubilization and a subsequent membrane flotation analysis indicated that the accumulation of nucleoprotein, viral polymerases, NA, and matrix protein 1 (M1 in the lipid raft fraction was delayed without HA. Based on our results, we inferred that HA plays a role in the accumulation of viral components, including bundled vRNPs, at the lipid raft.

Influenza A Virus Hemagglutinin is Required for the Assembly of Viral Components Including Bundled vRNPs at the Lipid Raft.

Science.gov (United States)

Takizawa, Naoki; Momose, Fumitaka; Morikawa, Yuko; Nomoto, Akio

2016-09-10

The influenza glycoproteins, hemagglutinin (HA) and neuraminidase (NA), which are associated with the lipid raft, have the potential to initiate virion budding. However, the role of these viral proteins in infectious virion assembly is still unclear. In addition, it is not known how the viral ribonucleoprotein complex (vRNP) is tethered to the budding site. Here, we show that HA is necessary for the efficient progeny virion production and vRNP packaging in the virion. We also found that the level of HA does not affect the bundling of the eight vRNP segments, despite reduced virion production. Detergent solubilization and a subsequent membrane flotation analysis indicated that the accumulation of nucleoprotein, viral polymerases, NA, and matrix protein 1 (M1) in the lipid raft fraction was delayed without HA. Based on our results, we inferred that HA plays a role in the accumulation of viral components, including bundled vRNPs, at the lipid raft.

The immunomodulator, ammonium trichloro[1,2-ethanediolato-O,O']-tellurate, suppresses the propagation of herpes simplex virus 2 by reducing the infectivity of the virus progeny.

Science.gov (United States)

Sheinboim, D; Hindiyeh, M; Mendelson, E; Albeck, M; Sredni, B; Dovrat, S

2015-07-01

Persistent investigations for the identification of novel anti-herpetic drugs are being conducted worldwide, as current treatment options are sometimes insufficient. The immunomodulator, ammonium trichloro[1,2‑ethanediolato‑O,O']‑tellurate (AS101), a non‑toxic tellurium (Ⅳ) compound, has been shown to exhibit anti‑viral activity against a variety of viruses in cell cultures and in animal models. In the present study, the anti‑viral activity of AS101 against herpes simplex virus (HSV)‑1 and 2 was investigated in vitro. The results demonstrated that AS101 significantly restricted HSV‑2-induced plaque formation and reduced the infectivity of the HSV‑2 yield, while HSV‑1 was affected to a lesser extent. The incubation of mature HSV‑1 and HSV‑2 viruses with AS101 had no effect on viral infectivity, indicating that the compound interrupts de novo viral synthesis. The addition of AS101 at up to 9 h post‑infection had almost the same effect as did the addition of the drug together with the virus (it maintained 80% of its total anti‑viral capacity). Quantitative PCR and immunofluoresence staining of viral structural proteins revealed that the viral DNA and protein synthesis stages were not interrupted by the administration of AS101. By contrast, in the presence of the compound, significantly fewer viable viruses (≥2 log reduction) were recovered from the AS10‑treated cell cultures. Of note, when we determined the viability of the intracellular virus, formed in the presence of the compound, a less severe (≤1 log) effect was observed. Taken together, these data strongly suggest that AS101 primarily interferes with late stages of viral replication, such as viral particle envelopment or egress, leading to the production of a defective virus progeny.

Targeting APOBEC3A to the viral nucleoprotein complex confers antiviral activity

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Strebel Klaus

2007-08-01

Full Text Available Abstract Background APOBEC3 (A3 proteins constitute a family of cytidine deaminases that provide intracellular resistance to retrovirus replication and to transposition of endogenous retroelements. A3A has significant homology to the C-terminus of A3G but has only a single cytidine deaminase active site (CDA, unlike A3G, which has a second N-terminal CDA previously found to be important for Vif sensitivity and virus encapsidation. A3A is packaged into HIV-1 virions but, unlike A3G, does not have antiviral properties. Here, we investigated the reason for the lack of A3A antiviral activity. Results Sequence alignment of A3G and A3A revealed significant homology of A3A to the C-terminal region of A3G. However, while A3G co-purified with detergent-resistant viral nucleoprotein complexes (NPC, virus-associated A3A was highly detergent-sensitive leading us to speculate that the ability to assemble into NPC may be a property conveyed by the A3G N-terminus. To test this model, we constructed an A3G-3A chimeric protein, in which the N-terminal half of A3G was fused to A3A. Interestingly, the A3G-3A chimera was packaged into HIV-1 particles and, unlike A3A, associated with the viral NPC. Furthermore, the A3G-3A chimera displayed strong antiviral activity against HIV-1 and was sensitive to inhibition by HIV-1 Vif. Conclusion Our results suggest that the A3G N-terminal domain carries determinants important for targeting the protein to viral NPCs. Transfer of this domain to A3A results in A3A targeting to viral NPCs and confers antiviral activity.

Nucleic Acid-Based Approaches for Detection of Viral Hepatitis

Science.gov (United States)

Behzadi, Payam; Ranjbar, Reza; Alavian, Seyed Moayed

2014-01-01

Context: To determining suitable nucleic acid diagnostics for individual viral hepatitis agent, an extensive search using related keywords was done in major medical library and data were collected, categorized, and summarized in different sections. Results: Various types of molecular biology tools can be used to detect and quantify viral genomic elements and analyze the sequences. These molecular assays are proper technologies for rapidly detecting viral agents with high accuracy, high sensitivity, and high specificity. Nonetheless, the application of each diagnostic method is completely dependent on viral agent. Conclusions: Despite rapidity, automation, accuracy, cost-effectiveness, high sensitivity, and high specificity of molecular techniques, each type of molecular technology has its own advantages and disadvantages. PMID:25789132

The full-length E1-circumflexE4 protein of human papillomavirus type 18 modulates differentiation-dependent viral DNA amplification and late gene expression

International Nuclear Information System (INIS)

Wilson, Regina; Ryan, Gordon B.; Knight, Gillian L.; Laimins, Laimonis A.; Roberts, Sally

2007-01-01

Activation of the productive phase of the human papillomavirus (HPV) life cycle in differentiated keratinocytes is coincident with high-level expression of E1-circumflexE4 protein. To determine the role of E1-circumflexE4 in the HPV replication cycle, we constructed HPV18 mutant genomes in which expression of the full-length E1-circumflexE4 protein was abrogated. Undifferentiated keratinocytes containing mutant genomes showed enhanced proliferation when compared to cells containing wildtype genomes, but there were no differences in maintenance of viral episomes. Following differentiation, cells with mutant genomes exhibited reduced levels of viral DNA amplification and late gene expression, compared to wildtype genome-containing cells. This indicates that HPV18 E1-circumflexE4 plays an important role in regulating HPV late functions, and it may also function in the early phase of the replication cycle. Our finding that full-length HPV18 E1-circumflexE4 protein plays a significant role in promoting viral genome amplification concurs with a similar report with HPV31, but is in contrast to an HPV11 study where viral DNA amplification was not dependent on full-length E1-circumflexE4 expression, and to HPV16 where only C-terminal truncations in E1-circumflexE4 abrogated vegetative genome replication. This suggests that type-specific differences exist between various E1-circumflexE4 proteins

Content Recommendation for Viral Social Influence

DEFF Research Database (Denmark)

Ivanov, Sergei; Theocharidis, Konstantinos; Terrovitis, Manolis

2017-01-01

How do we create content that will become viral in a whole network after we share it with friends or followers? Significant research activity has been dedicated to the problem of strategically selecting a seed set of initial adopters so as to maximize a meme’s spread in a network. This line of work...... assumes that the success of such a campaign depends solely on the choice of a tunable seed set of adopters, while the way users perceive the propagated meme is fixed. Yet, in many real-world settings, the opposite holds: a meme’s propagation depends on users’ perceptions of its tunable characteristics...

Interplay Among Constitutes of Ebola Virus: Nucleoprotein, Polymerase L, Viral Proteins

Science.gov (United States)

Zhang, Minchuan; He, Peiming; Su, Jing; Singh, Dadabhai T.; Su, Hailei; Su, Haibin

Ebola virus is a highly lethal filovirus, claimed thousands of people in its recent outbreak. Seven viral proteins constitute ebola viral structure, and four of them (nucleoprotein (NP), polymerase L, VP35 and VP30) participate majorly in viral replication and transcription. We have elucidated a conformation change of NP cleft by VP35 NP-binding protein domains through superimposing two experimental NP structure images and discussed the function of this conformation change in the replication and transcription with polymerase complex (L, VP35 and VP30). The important roles of VP30 in viral RNA synthesis have also been discussed. A “tapping” model has been proposed in this paper for a better understanding of the interplay among the four viral proteins (NP, polymerase L, VP35 and VP30). Moreover, we have pinpointed some key residue changes on NP (both NP N- and C-terminal) and L between Reston and Zaire by computational studies. Together, this paper provides a description of interactions among ebola viral proteins (NP, L, VP35, VP30 and VP40) in viral replication and transcription, and sheds light on the complex system of viral reproduction.

Perinatal Exposure to Environmental Tobacco Smoke (ETS Enhances Susceptibility to Viral and Secondary Bacterial Infections

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Jocelyn A. Claude

2012-10-01

Full Text Available Studies suggest childhood exposure to environmental tobacco smoke (ETS leads to increased incidence of infections of the lower respiratory tract. The objective of this study was to determine whether perinatal exposure to ETS increases the incidence, morbidity and severity of respiratory influenza infection and whether a secondary bacterial challenge at the peak of a pre-existing viral infection creates an enhanced host-pathogen susceptibility to an opportunistic infection. Timed-pregnant female Balb/c mice were exposed to either ETS for 6 h/day, 7 d/week beginning on gestation day 14 and continuing with the neonates to 6 weeks of age. Control animals were exposed to filtered air (FA. At the end of exposure, mice were intranasally inoculated with a murine-adapted influenza A. One week later, an intranasal inoculation of S. aureus bacteria was administered. The respective treatment groups were: bacteria only, virus only or virus+bacteria for both FA and ETS-exposed animals for a total of six treatment groups. Animal behavior and body weights were documented daily following infection. Mice were necropsied 1-day post-bacterial infection. Bronchoalveolar lavage fluid (BALF cell analysis demonstrated perinatal exposure to ETS, compared to FA, leads to delayed but enhanced clinical symptoms and enhanced total cell influx into the lungs associated with viral infection followed by bacterial challenge. Viral infection significantly increases the number of neutrophils entering the lungs following bacterial challenge with either FA or ETS exposure, while the influx of lymphocytes and monocytes is significantly enhanced only by perinatal ETS exposure. There is a significant increase in peribronchiolar inflammation following viral infection in pups exposed to ETS compared with pups exposed to FA, but no change is noted in the degree of lung injury between FA and ETS-exposed animals following bacterial challenge. The data suggests perinatal exposure to ETS

The ultrasonographic changes of gallbladder wall and the corresponding hepatic pathology in patients with chronic viral hepatitis

International Nuclear Information System (INIS)

Zhang Haiying; Meng Fankun; Ding Huiguo

2006-01-01

Objective: To investigate the relationship between the ultrasonographic changes of gallbladder wall and the hepatic inflammation grading as well as fibrostic staging using ultrasound examination in patients with chronic viral hepatitis, and to survey the diagnostic standard for viral related cholecystitis. Methods: Five hundreds and nineteen chronic viral hepatitis patients and 104 normal control subjects were enrolled in the study. Ultrasound guided liver biopsy was performed in all patients with chronic viral hepatitis, in which the hepatic fibrostic stages(S) were divided into SI (n=148), S2(n=170), S3-4(n 201 ); and hepatic inflammation grades (G) were divided into G1 (n=124 ), G2 (n=204), G3 (n=191). The ultrasound scan was performed within 7 days after liver biopsy. The relationship between ultrasonographic changes of gallbladder and the hepatic inflammation grades and fibrostic stages were analyzed using statistic soft ware SPSS 11.5 for windows. Results: The percentage of the thickened gallbladder wall were 55%, 87%, 96% in S1, S2, S3-4, respectively, and were 45%, 82%, 95% in G1, G2, G3-4, respectively. Significant difference was revealed between G1 and G2, as well as between G2 and G3-4, with P < 0.05. Conclusion: A significant, positive correlative relationship exists between the ultrasonographic changes of gall-bladder wall and the hepatic inflammation grading and fibrostic staging in patients with chronic viral hepatitis. (authors)

Reconstructing viral genomes from the environment using fosmid clones: the case of haloviruses.

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Inmaculada Garcia-Heredia

Full Text Available BACKGROUND: Metaviriomes, the viral genomes present in an environment, have been studied by direct sequencing of the viral DNA or by cloning in small insert libraries. The short reads generated by both approaches make it very difficult to assemble and annotate such flexible genomic entities. Many environmental viruses belong to unknown groups or prey on uncultured and little known cellular lineages, and hence might not be present in databases. METHODOLOGY AND PRINCIPAL FINDINGS: Here we have used a different approach, the cloning of viral DNA into fosmids before sequencing, to obtain natural contigs that are close to the size of a viral genome. We have studied a relatively low diversity extreme environment: saturated NaCl brines, which simplifies the analysis and interpretation of the data. Forty-two different viral genomes were retrieved, and some of these were almost complete, and could be tentatively identified as head-tail phages (Caudovirales. CONCLUSIONS AND SIGNIFICANCE: We found a cluster of phage genomes that most likely infect Haloquadratum walsbyi, the square archaeon and major component of the community in these hypersaline habitats. The identity of the prey could be confirmed by the presence of CRISPR spacer sequences shared by the virus and one of the available strain genomes. Other viral clusters detected appeared to prey on the Nanohaloarchaea and on the bacterium Salinibacter ruber, covering most of the diversity of microbes found in this type of environment. This approach appears then as a viable alternative to describe metaviriomes in a much more detailed and reliable way than by the more common approaches based on direct sequencing. An example of transfer of a CRISPR cluster including repeats and spacers was accidentally found supporting the dynamic nature and frequent transfer of this peculiar prokaryotic mechanism of cell protection.

Heterogeneous nuclear ribonuclear protein K interacts with Sindbis virus nonstructural proteins and viral subgenomic mRNA

International Nuclear Information System (INIS)

Burnham, Andrew J.; Gong, Lei; Hardy, Richard W.

2007-01-01

Alphaviruses are a group of arthropod-borne human and animal pathogens that can cause epidemics of significant public health and economic consequence. Alphavirus RNA synthesis requires four virally encoded nonstructural proteins and probably a number of cellular proteins. Using comparative two-dimensional electrophoresis we were able to identify proteins enriched in cytoplasmic membrane fractions containing viral RNA synthetic complexes following infection with Sindbis virus. Our studies demonstrated the following: (i) the host protein hnRNP K is enriched in cytoplasmic membrane fractions following Sindbis virus infection, (ii) viral nonstructural proteins co-immunoprecipitate with hnRNP K, (iii) nsP2 and hnRNP K co-localize in the cytoplasm of Sindbis virus infected cells, (iv) Sindbis virus subgenomic mRNA, but not genomic RNA co-immunoprecipitates with hnRNP K, (v) viral RNA does not appear to be required for the interaction of hnRNP K with the nonstructural proteins. Potential functions of hnRNP K during virus replication are discussed

Insect symbiotic bacteria harbour viral pathogens for transovarial transmission.

Science.gov (United States)

Jia, Dongsheng; Mao, Qianzhuo; Chen, Yong; Liu, Yuyan; Chen, Qian; Wu, Wei; Zhang, Xiaofeng; Chen, Hongyan; Li, Yi; Wei, Taiyun

2017-03-06

Many insects, including mosquitoes, planthoppers, aphids and leafhoppers, are the hosts of bacterial symbionts and the vectors for transmitting viral pathogens 1-3 . In general, symbiotic bacteria can indirectly affect viral transmission by enhancing immunity and resistance to viruses in insects 3-5 . Whether symbiotic bacteria can directly interact with the virus and mediate its transmission has been unknown. Here, we show that an insect symbiotic bacterium directly harbours a viral pathogen and mediates its transovarial transmission to offspring. We observe rice dwarf virus (a plant reovirus) binding to the envelopes of the bacterium Sulcia, a common obligate symbiont of leafhoppers 6-8 , allowing the virus to exploit the ancient oocyte entry path of Sulcia in rice leafhopper vectors. Such virus-bacterium binding is mediated by the specific interaction of the viral capsid protein and the Sulcia outer membrane protein. Treatment with antibiotics or antibodies against Sulcia outer membrane protein interferes with this interaction and strongly prevents viral transmission to insect offspring. This newly discovered virus-bacterium interaction represents the first evidence that a viral pathogen can directly exploit a symbiotic bacterium for its transmission. We believe that such a model of virus-bacterium communication is a common phenomenon in nature.

Construction of green fluorescent protein-tagged recombinant iridovirus to assess viral replication.

Science.gov (United States)

Huang, Youhua; Huang, Xiaohong; Cai, Jia; Ye, Fuzhou; Guan, Liya; Liu, Hong; Qin, Qiwei

2011-09-01

Green fluorescent protein-tagged recombinant virus has been successfully applied to observing the infective dynamics and evaluating viral replication. Here, we identified soft-shelled turtle iridovirus (STIV) ORF55 as an envelope protein (VP55), and developed a recombinant STIV expressing an enhanced green fluorescent protein (EGFP) fused to VP55 (EGFP-STIV). Recombinant EGFP-STIV shared similar single-step growth curves and ultrastructural morphology with wild type STIV (wt-STIV). The green fluorescence distribution during EGFP-STIV infection was consistent with the intracellular distribution of VP55 which was mostly co-localized with virus assembly sites. Furthermore, EGFP-STIV could be used to evaluate viral replication conveniently under drug treatment, and the result showed that STIV replication was significantly inhibited after the addition of antioxidant pyrrolidine dithiocarbamate (PDTC). Thus, the EGFP-tagged recombinant iridovirus will not only be useful for further investigations on the viral replicative dynamics, but also provide an alternative simple strategy to screen for antiviral substances. Copyright © 2011 Elsevier B.V. All rights reserved.

CT images of infantile viral encephalitis

International Nuclear Information System (INIS)

Sugimoto, Tateo; Okazaki, Hitoshi; Woo, Man

1985-01-01

Cranial CT scanning was undertaken in 40 patients with infantile viral encephalitis seen from 1977 to 1983. According to the pathogenic viruses, abnormal CT findings were detected most frequently in cases of herpes simplex encephalitis (HSE), followed by non-eruptive viral encephalitis, measles encephalitis, and rubella encephalitis in that order, which coincided well with neurological prognosis. Although CT findings lay within a normal range in cases of measles encephalitis, except a case in which cerebral ventricle was slightly dilated, the degree of consciousness disturbance was unfavorable and it persisted long. This revealed that there is no distinct correlation between the degree of consciousness disturbance and CT findings. Normal CT findings were detected in 13% of patients aged less than 5 years and 76.5% of patients aged 5 years or more. In many patients who had an attack of viral encephalitis at the age of 5 years or more, epileptic seizures occurred frequently, even though CT findings were normal. (Namekawa, K.)

Detection of viral hemorrhagic septicemia virus

Science.gov (United States)

Winton, James; Kurath, Gael; Batts, William

2007-01-01

Viral hemorrhagic septicemia virus (VHSV) is considered to be one of the most important viral pathogens of finfish and is listed as reportable by many nations and international organizations (Office International des Epizooties 2006). Prior to 1988, VHSV was thought to be limited to Europe (Wolf 1988; Smail 1999). Subsequently, it was shown that the virus is endemic among many marine and anadromous fish species in both the Pacific and Atlantic Oceans (Meyers and Winton 1995; Skall et al. 2005). Genetic analysis reveals that isolates of VHSV can be divided into four genotypes that generally correlate with geographic location with the North American isolates generally falling into VHSV Genotype IV (Snow et al. 2004). In 2005-2006, reports from the Great Lakes region indicated that wild fish had experienced disease or, in some cases, very large die-offs from VHSV (Elsayed et al. 2006, Lumsden et al. 2007). The new strain from the Great Lakes, now identified as VHSV Genotype IVb, appears most closely related to isolates of VHSV from mortalities that occurred during 2000-2004 in rivers and near-shore areas of New Brunswick and Nova Scotia, Canada (Gagne et al. 2007). The type IVb isolate found in the Great Lakes region is the only strain outside of Europe that has been associated with significant mortality in freshwater species.

Tissue viral load variability in chronic hepatitis C.

LENUS (Irish Health Repository)

Fanning, L

2012-02-03

OBJECTIVE: Liver biopsy is regarded as the gold standard for assessing disease activity in chronic hepatitis C, but sampling error is a potential limitation. Whether sampling variability applies equally to viral load assessment as it does to histology is uncertain. To examine this, we compared viral load between right- and left-lobe biopsy specimens from patients infected with hepatitis C virus (HCV). METHODS: Bilobe biopsies were taken from 16 patients who were serum positive for HCV RNA by reverse transcription-polymerase chain reaction. Genotype was identified by reverse line probe hybridization. There was an absence of competing risk factors for infectious and other liver diseases in this patient group. Histology and hepatic viral load were assessed blindly. None of the patients had received antiviral therapy at the time of study. RESULTS: Detection of HCV in right and left lobes was concordant with serum positivity in all cases. The viral load between lobes was highly correlated (p = 0.0003, r = 0.79). In contrast, the histological activity indices of inflammation and fibrosis\\/cirrhosis were poorly correlated between lobes (p = 0.038, r = 0.60, and p = 0.098, r = 0.50, respectively). CONCLUSION: Hepatic viral load variability does not suffer from the same degree of heterogeneity of sampling variability as does histology.

Leader protein of encephalomyocarditis virus binds zinc, is phosphorylated during viral infection, and affects the efficiency of genome translation.

Science.gov (United States)

Dvorak, C M; Hall, D J; Hill, M; Riddle, M; Pranter, A; Dillman, J; Deibel, M; Palmenberg, A C

2001-11-25

Encephalomyocarditis virus (EMCV) is the prototype member of the cardiovirus genus of picornaviruses. For cardioviruses and the related aphthoviruses, the first protein segment translated from the plus-strand RNA genome is the Leader protein. The aphthovirus Leader (173-201 amino acids) is an autocatalytic papain-like protease that cleaves translation factor eIF-4G to shut off cap-dependent host protein synthesis during infection. The less characterized cardioviral Leader is a shorter protein (67-76 amino acids) and does not contain recognizable proteolytic motifs. Instead, these Leaders have sequences consistent with N-terminal zinc-binding motifs, centrally located tyrosine kinase phosphorylation sites, and C-terminal, acid-rich domains. Deletion mutations, removing the zinc motif, the acid domain, or both domains, were engineered into EMCV cDNAs. In all cases, the mutations gave rise to viable viruses, but the plaque phenotypes in HeLa cells were significantly smaller than for wild-type virus. RNA transcripts containing the Leader deletions had reduced capacity to direct protein synthesis in cell-free extracts and the products with deletions in the acid-rich domains were less effective substrates at the L/P1 site, for viral proteinase 3Cpro. Recombinant EMCV Leader (rL) was expressed in bacteria and purified to homogeneity. This protein bound zinc stoichiometrically, whereas protein with a deletion in the zinc motif was inactive. Polyclonal mouse sera, raised against rL, immunoprecipitated Leader-containing precursors from infected HeLa cell extracts, but did not detect significant pools of the mature Leader. However, additional reactions with antiphosphotyrosine antibodies show that the mature Leader, but not its precursors, is phosphorylated during viral infection. The data suggest the natural Leader may play a role in regulation of viral genome translation, perhaps through a triggering phosphorylation event.

Inhibition of melanoma growth by subcutaneous administration of hTERTC27 viral cocktail in C57BL/6 mice.

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Longfei Huo

Full Text Available BACKGROUND: hTERTC27 is a 27 kDa C-terminal polypeptide of human telomerase reverse transcriptase that has previously been shown to reduce tumorigenicity of HeLa cells and suppress growth of xenografted glioblastoma in nude mice. Although ectopic expression of hTERTC27 upregulated genes that are involved in apoptosis, cell cycle, and immune response, the mechanism for hTERTC27-induced tumor suppression has not been completely elucidated. Since hTERT was identified as a universal tumor-associated antigen, we hypothesize that hTERTC27 inhibits tumor growth in vivo through activation of anti-tumor immune response. METHODOLOGY/PRINCIPAL FINDING: Immunocompetent C57BL/6 mice were used for mouse B16 melanoma model. Mice bearing B16 melanoma were administered rAAV-/rAdv viral cocktail expressing hTERTC27, and tumor growth was monitored after viral cocktail treatment. Blood and splenocytes were used to determine the level of cytokines and the activity of immune cells, respectively. B16 tumor growth was significantly inhibited by subcutaneous administration of a single dose of 1.5×10(11 vg rAAV-hTERTC27 and 2.5×10(9 pfu rAdv-hTERTC27 viral cocktail (rAAV-/rAdv-hTERTC27. The population and cytotoxicity of NK cells in the mice were significantly augmented by rAAV-/rAdv-hTERTC27 treatment, and selective depletion of the NK cell population in mice by intraperitoneal injection of anti-GM1 antibody abrogated the growth suppression of melanoma induced by rAAV-/rAdv-hTERTC27 administration. CONCLUSION: Activation of NK cells by administration of rAAV-/rAdv-hTERTC27 is critical for growth suppression of melanoma in mouse model.

Kallistatin Ameliorates Influenza Virus Pathogenesis by Inhibition of Kallikrein-Related Peptidase 1-Mediated Cleavage of Viral Hemagglutinin

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Leu, Chia-Hsing; Yang, Mei-Lin; Chung, Nai-Hui; Huang, Yen-Jang; Su, Yu-Chu; Chen, Yi-Cheng; Lin, Chia-Cheng; Shieh, Gia-Shing; Chang, Meng-Ya; Wang, Shainn-Wei; Chang, Yao; Chao, Julie; Chao, Lee

2015-01-01

Proteolytic cleavage of the hemagglutinin (HA) of influenza virus by host trypsin-like proteases is required for viral infectivity. Some serine proteases are capable of cleaving influenza virus HA, whereas some serine protease inhibitors (serpins) inhibit the HA cleavage in various cell types. Kallikrein-related peptidase 1 (KLK1, also known as tissue kallikrein) is a widely distributed serine protease. Kallistatin, a serpin synthesized mainly in the liver and rapidly secreted into the circulation, forms complexes with KLK1 and inhibits its activity. Here, we investigated the roles of KLK1 and kallistatin in influenza virus infection. We show that the levels of KLK1 increased, whereas those of kallistatin decreased, in the lungs of mice during influenza virus infection. KLK1 cleaved H1, H2, and H3 HA molecules and consequently enhanced viral production. In contrast, kallistatin inhibited KLK1-mediated HA cleavage and reduced viral production. Cells transduced with the kallistatin gene secreted kallistatin extracellularly, which rendered them more resistant to influenza virus infection. Furthermore, lentivirus-mediated kallistatin gene delivery protected mice against lethal influenza virus challenge by reducing the viral load, inflammation, and injury in the lung. Taking the data together, we determined that KLK1 and kallistatin contribute to the pathogenesis of influenza virus by affecting the cleavage of the HA peptide and inflammatory responses. This study provides a proof of principle for the potential therapeutic application of kallistatin or other KLK1 inhibitors for influenza. Since proteolytic activation also enhances the infectivity of some other viruses, kallistatin and other kallikrein inhibitors may be explored as antiviral agents against these viruses. PMID:26149981

Aspirin-triggered resolvin D1 reduces pneumococcal lung infection and inflammation in a viral and bacterial coinfection pneumonia model.

Science.gov (United States)

Wang, Hao; Anthony, Desiree; Yatmaz, Selcuk; Wijburg, Odilia; Satzke, Catherine; Levy, Bruce; Vlahos, Ross; Bozinovski, Steven

2017-09-15

Formyl peptide receptor 2/lipoxin A 4 (LXA 4 ) receptor (Fpr2/ALX) co-ordinates the transition from inflammation to resolution during acute infection by binding to distinct ligands including serum amyloid A (SAA) and Resolvin D1 (RvD1). Here, we evaluated the proresolving actions of aspirin-triggered RvD1 (AT-RvD1) in an acute coinfection pneumonia model. Coinfection with Streptococcus pneumoniae and influenza A virus (IAV) markedly increased pneumococcal lung load and neutrophilic inflammation during the resolution phase. Fpr2/ALX transcript levels were increased in the lungs of coinfected mice, and immunohistochemistry identified prominent Fpr2/ALX immunoreactivity in bronchial epithelial cells and macrophages. Levels of circulating and lung SAA were also highly increased in coinfected mice. Therapeutic treatment with exogenous AT-RvD1 during the acute phase of infection (day 4-6 post-pneumococcal inoculation) significantly reduced the pneumococcal load. AT-RvD1 also significantly reduced neutrophil elastase (NE) activity and restored total antimicrobial activity in bronchoalveolar lavage (BAL) fluid (BALF) of coinfected mice. Pneumonia severity, as measured by quantitating parenchymal inflammation or alveolitis was significantly reduced with AT-RvD1 treatment, which also reduced the number of infiltrating lung neutrophils and monocytes/macrophages as assessed by flow cytometry. The reduction in distal lung inflammation in AT-RvD1-treated mice was not associated with a significant reduction in inflammatory and chemokine mediators. In summary, we demonstrate that in the coinfection setting, SAA levels were persistently increased and exogenous AT-RvD1 facilitated more rapid clearance of pneumococci in the lungs, while concurrently reducing the severity of pneumonia by limiting excessive leukocyte chemotaxis from the infected bronchioles to distal areas of the lungs. © 2017 The Author(s).

Dengue viral infection monitoring from diagnostic to recovery using Raman spectroscopy

International Nuclear Information System (INIS)

Firdous, Shamaraz; Anwar, Shahzad

2015-01-01

Raman spectroscopy has been found useful for monitoring the dengue patient diagnostic and recovery after infection. In the present work, spectral changes that occurred in the blood sera of a dengue infected patient and their possible utilization for monitoring of infection and recovery were investigated using 532 nm wavelength of light. Raman spectrum peaks for normal and after recovery of dengue infection are observed at 1527, 1170, 1021 cm −1 attributed to guanine, adenine, TRP (protein) carbohydrates peak for solids, and skeletal C–C stretch of lipids acyl chains. Where in the dengue infected patient Raman peaks are at 1467, 1316, 1083, and 860 attributed to CH2/CH3 deformation of lipids and collagen, guanine (B, Z-marker), lipids and protein bands. Due to antibodies and antigen reactions the portions and lipids concentration totally changes in dengue viral infection compared to normal blood. These chemical changes in blood sera of dengue viral infection in human blood may be used as possible markers to indicate successful remission and suggest that Raman spectroscopy may provide a rapid optical method for continuous monitoring or evaluation of a protein bands and an antibodies population. Accumulate acquisition mode was used to reduce noise and thermal fluctuation and improve signal to noise ratio. This in vitro dengue infection monitoring methodology will lead in vivo noninvasive on-line monitoring and screening of viral infected patients and their recovery. (letter)

Protruding Features of Viral Capsids Are Clustered on Icosahedral Great Circles.

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David P Wilson

Full Text Available Spherical viruses are remarkably well characterized by the Triangulation (T number developed by Casper and Klug. The T-number specifies how many viral capsid proteins are required to cover the virus, as well as how they are further subdivided into pentamer and hexamer subunits. The T-number however does not constrain the orientations of these proteins within the subunits or dictate where the proteins should place their protruding features. These protrusions often take the form of loops, spires and helices, and are significant because they aid in stability of the capsid as well as recognition by the host organism. Until now there has be no overall understanding of the placement of protrusions for spherical viruses, other than they have icosahedral symmetry. We constructed a set of gauge points based upon the work affine extensions of Keef and Twarock, which have fixed relative angular locations with which to measure the locations of these features. This work adds a new element to our understanding of the geometric arrangement of spherical viral capsid proteins; chiefly that the locations of protruding features are not found stochastically distributed in an icosahedral manner across the viral surface, but instead these features are found only in specific locations along the 15 icosahedral great circles. We have found that this result holds true as the T number and viral capsids size increases, suggesting an underlying geometric constraint on their locations. This is in spite of the fact that the constraints on the pentamers and hexamer orientations change as a function of T-number, as you need to accommodate more hexamers in the same solid angle between pentamers. The existence of this angular constraint of viral capsids suggests that there is a fitness or energetic benefit to the virus placing its protrusions in this manner. This discovery may have profound impacts on identifying and eliminating viral pathogens, understanding evolutionary

The effect of cranberry juice and cranberry proanthocyanidins on the infectivity of human enteric viral surrogates.

Science.gov (United States)

Su, Xiaowei; Howell, Amy B; D'Souza, Doris H

2010-06-01

The effect of cranberry juice (CJ) and cranberry proanthocyanidins (PAC) on the infectivity of human enteric virus surrogates, murine norovirus (MNV-1), feline calicivirus (FCV-F9), MS2(ssRNA) bacteriophage, and phiX-174(ssDNA) bacteriophage was studied. Viruses at high (approximately 7 log(10) PFU/ml) or low (approximately 5 log(10) PFU/ml) titers were mixed with equal volumes of CJ, 0.30, 0.60, and 1.20 mg/ml final PAC concentration, or water and incubated for 1 h at room temperature. Viral infectivity after treatments was evaluated using standardized plaque assays. At low viral titers, FCV-F9 was undetectable after exposure to CJ or the three tested PAC solutions. MNV-1 was reduced by 2.06 log(10) PFU/ml with CJ, and 2.63, 2.75, and 2.95 log(10) PFU/ml with 0.15, 0.30, and 0.60 mg/ml PAC, respectively. MS2 titers were reduced by 1.14 log(10) PFU/ml with CJ, and 0.55, 0.80, and 0.96 log(10) PFU/ml with 0.15, 0.30, and 0.60 mg/ml PAC, respectively. phi-X174 titers were reduced by 1.79 log(10) PFU/ml with CJ, and 1.95, 3.67, and 4.98 log(10) PFU/ml with PAC at 0.15, 0.30, and 0.60 mg/ml, respectively. Experiments using high titers showed similar trends but with decreased effects. CJ and PAC show promise as natural antivirals that could potentially be exploited for foodborne viral illness treatment and prevention. 2010 Elsevier Ltd. All rights reserved.

Institute of Medicine's Report on Viral Hepatitis

Centers for Disease Control (CDC) Podcasts

2010-05-18

In this podcast, Dr. John Ward, Director of CDC’s Division of Viral Hepatitis, discusses the 2010 report, Hepatitis and Liver Cancer: A National Strategy for Prevention and Control of Hepatitis B and C, from the Institute of Medicine.  Created: 5/18/2010 by National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP).   Date Released: 5/18/2010.

Viral and cellular requirements for the budding of Feline Endogenous Retrovirus RD-114

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Fukuma Aiko

2011-12-01

Full Text Available Abstract Background RD-114 virus is a feline endogenous retrovirus and produced as infectious viruses in some feline cell lines. Recently, we reported the contamination of an infectious RD-114 virus in a proportion of live attenuated vaccines for dogs and cats. It is very difficult to completely knock out the RD-114 proviruses from cells, as endogenous retroviruses are usually integrated multiply into the host genome. However, it may be possible to reduce the risk of contamination of RD-114 virus by regulating the viral release from cells. Results In this study, to understand the molecular mechanism of RD-114 virus budding, we attempted to identify the viral and cellular requirements for RD-114 virus budding. Analyses of RD-114 L-domain mutants showed that the PPPY sequence in the pp15 region of Gag plays a critical role in RD-114 virus release as viral L-domain. Furthermore, we investigated the cellular factors required for RD-114 virus budding. We demonstrated that RD-114 virus release was inhibited by overexpression of dominant negative mutants of Vps4A, Vps4B, and WWP2. Conclusions These results strongly suggest that RD-114 budding utilizes the cellular multivesicular body sorting pathway similar to many other retroviruses.

Lymphocyte subset contents in cerebrospinal fluid of children with viral encephalitis

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An-Ran Xu

2016-06-01

Full Text Available Objective: To study the lymphocyte subset contents in cerebrospinal fluid of children with viral encephalitis and their correlation with disease. Methods: Children with viral encephalitis were selected as VE group, children excluded of central nervous system infection by lumbar puncture or children without central nervous system diseases but receiving surgery with spinal anesthesia were selected as control group, and then cerebrospinal fluid and serum were collected to detect lymphocyte subset contents, nerve injury molecule contents as well as inflammatory response indicators and oxidative stress response indicators. Results: CD3+, CD3+CD4+, CD4/CD8 and CD16+CD56+ in cerebrospinal fluid of VE group were lower than those of control group, and both CD3+CD8+ and CD19+ were higher than those of control group; CD3+, CD3+CD4+, CD4/CD8 and CD16+CD56+ in cerebrospinal fluid of children with abnormal MRI were lower than those of children with normal MRI, and both CD3+CD8+ and CD19+ were higher than those of children with normal MRI; NSE, MBP, S-100 and NPT contents in cerebrospinal fluid and serum of VE group were significantly higher than those of control group and had good correlation with lymphocyte subset contents; MMP9, TNF-α and IL-6 contents in cerebrospinal fluid of VE group were significantly higher than those of control group, and SOD and GSH-Px contents were significantly lower than those of control group and had good correlation with lymphocyte subset contents. Conclusions: CD4+/CD8+T lymphocyte ratio and NK cell content decrease, and B lymphocyte content increases in cerebrospinal fluid of children with viral encephalitis, and lymphocyte subset contents have inhibitory effect on MRI manifestation, degree of inflammatory response and oxidative stress response.

Anti-viral RNA silencing: do we look like plants ?

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Lecellier Charles-Henri

2006-01-01

Full Text Available Abstract The anti-viral function of RNA silencing was first discovered in plants as a natural manifestation of the artificial 'co-suppression', which refers to the extinction of endogenous gene induced by homologous transgene. Because silencing components are conserved among most, if not all, eukaryotes, the question rapidly arose as to determine whether this process fulfils anti-viral functions in animals, such as insects and mammals. It appears that, whereas the anti-viral process seems to be similarly conserved from plants to insects, even in worms, RNA silencing does influence the replication of mammalian viruses but in a particular mode: micro(miRNAs, endogenous small RNAs naturally implicated in translational control, rather than virus-derived small interfering (siRNAs like in other organisms, are involved. In fact, these recent studies even suggest that RNA silencing may be beneficial for viral replication. Accordingly, several large DNA mammalian viruses have been shown to encode their own miRNAs. Here, we summarize the seminal studies that have implicated RNA silencing in viral infection and compare the different eukaryotic responses.

Structural equation modelling of viral tropism reveals its impact on achieving viral suppression within 6 months in treatment-naive HIV-1-infected patients after combination antiretroviral therapy.

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Mengoli, Carlo; Andreis, Samantha; Scaggiante, Renzo; Cruciani, Mario; Bosco, Oliviero; Ferretto, Roberto; Leoni, Davide; Maffongelli, Gaetano; Basso, Monica; Torti, Carlo; Sarmati, Loredana; Andreoni, Massimo; Palù, Giorgio; Parisi, Saverio Giuseppe

2017-01-01

To evaluate the role of pre-treatment co-receptor tropism of plasma HIV on the achievement of viral suppression (plasma HIV RNA 1.69 log 10 copies/mL) at the sixth month of combination antiretroviral therapy (cART) in a cohort of naive patients using, for the first time in this context, a path analysis (PA) approach. Adult patients with chronic infection by subtype B HIV-1 were consecutively enrolled from the start of first-line cART (T0). Genotypic analysis of viral tropism was performed on plasma and interpreted using the bioinformatic tool Geno2pheno, with a false positive rate of 10%. A Bayesian network starting from the viro-immunological data at T0 and at the sixth month of treatment (T1) was set up and this model was evaluated using a PA approach. A total of 262 patients (22.1% bearing an X4 virus) were included; 178 subjects (67.9%) achieved viral suppression. A significant positive indirect effect of bearing X4 virus in plasma at T0 on log 10 HIV RNA at T1 was detected (P = 0.009), the magnitude of this effect was, however, over 10-fold lower than the direct effect of log 10 HIV RNA at T0 on log 10 HIV RNA at T1 (P = 0.000). Moreover, a significant positive indirect effect of bearing an X4 virus on log 10 HIV RNA at T0 (P = 0.003) was apparent. PA overcame the limitations implicit in common multiple regression analysis and showed the possible role of pre-treatment viral tropism at the recommended threshold on the outcome of plasma viraemia in naive patients after 6 months of therapy. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Non-Viral Deoxyribonucleoside Kinases

DEFF Research Database (Denmark)

Christiansen, Louise Slot; Munch-Petersen, Birgitte; Knecht, Wolfgang

2015-01-01

Deoxyribonucleoside kinases (dNKs) phosphorylate deoxyribonucleosides to their corresponding monophosphate compounds. dNks also phosphorylate deoxyribonucleoside analogues that are used in the treatment of cancer or viral infections. The study of the mammalian dNKs has therefore always been of gr...

The GAAS metagenomic tool and its estimations of viral and microbial average genome size in four major biomes.

Science.gov (United States)

Angly, Florent E; Willner, Dana; Prieto-Davó, Alejandra; Edwards, Robert A; Schmieder, Robert; Vega-Thurber, Rebecca; Antonopoulos, Dionysios A; Barott, Katie; Cottrell, Matthew T; Desnues, Christelle; Dinsdale, Elizabeth A; Furlan, Mike; Haynes, Matthew; Henn, Matthew R; Hu, Yongfei; Kirchman, David L; McDole, Tracey; McPherson, John D; Meyer, Folker; Miller, R Michael; Mundt, Egbert; Naviaux, Robert K; Rodriguez-Mueller, Beltran; Stevens, Rick; Wegley, Linda; Zhang, Lixin; Zhu, Baoli; Rohwer, Forest

2009-12-01

Metagenomic studies characterize both the composition and diversity of uncultured viral and microbial communities. BLAST-based comparisons have typically been used for such analyses; however, sampling biases, high percentages of unknown sequences, and the use of arbitrary thresholds to find significant similarities can decrease the accuracy and validity of estimates. Here, we present Genome relative Abundance and Average Size (GAAS), a complete software package that provides improved estimates of community composition and average genome length for metagenomes in both textual and graphical formats. GAAS implements a novel methodology to control for sampling bias via length normalization, to adjust for multiple BLAST similarities by similarity weighting, and to select significant similarities using relative alignment lengths. In benchmark tests, the GAAS method was robust to both high percentages of unknown sequences and to variations in metagenomic sequence read lengths. Re-analysis of the Sargasso Sea virome using GAAS indicated that standard methodologies for metagenomic analysis may dramatically underestimate the abundance and importance of organisms with small genomes in environmental systems. Using GAAS, we conducted a meta-analysis of microbial and viral average genome lengths in over 150 metagenomes from four biomes to determine whether genome lengths vary consistently between and within biomes, and between microbial and viral communities from the same environment. Significant differences between biomes and within aquatic sub-biomes (oceans, hypersaline systems, freshwater, and microbialites) suggested that average genome length is a fundamental property of environments driven by factors at the sub-biome level. The behavior of paired viral and microbial metagenomes from the same environment indicated that microbial and viral average genome sizes are independent of each other, but indicative of community responses to stressors and environmental conditions.

Host and Viral Factors in HIV-Mediated Bystander Apoptosis

Science.gov (United States)

Garg, Himanshu; Joshi, Anjali

2017-01-01

Human immunodeficiency virus (HIV) infections lead to a progressive loss of CD4 T cells primarily via the process of apoptosis. With a limited number of infected cells and vastly disproportionate apoptosis in HIV infected patients, it is believed that apoptosis of uninfected bystander cells plays a significant role in this process. Disease progression in HIV infected individuals is highly variable suggesting that both host and viral factors may influence HIV mediated apoptosis. Amongst the viral factors, the role of Envelope (Env) glycoprotein in bystander apoptosis is well documented. Recent evidence on the variability in apoptosis induction by primary patient derived Envs underscores the role of Env glycoprotein in HIV disease. Amongst the host factors, the role of C-C Chemokine Receptor type 5 (CCR5), a coreceptor for HIV Env, is also becoming increasingly evident. Polymorphisms in the CCR5 gene and promoter affect CCR5 cell surface expression and correlate with both apoptosis and CD4 loss. Finally, chronic immune activation in HIV infections induces multiple defects in the immune system and has recently been shown to accelerate HIV Env mediated CD4 apoptosis. Consequently, those factors that affect CCR5 expression and/or immune activation in turn indirectly regulate HIV mediated apoptosis making this phenomenon both complex and multifactorial. This review explores the complex role of various host and viral factors in determining HIV mediated bystander apoptosis. PMID:28829402

Hepatitis C Virus: Viral Quasispecies and Genotypes.

Science.gov (United States)

Tsukiyama-Kohara, Kyoko; Kohara, Michinori

2017-12-22

Hepatitis C virus (HCV) mainly replicates in the cytoplasm, where it easily establishes persistent infection, resulting in chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Due to its high rate of mutation, HCV forms viral quasispecies, categorized based on the highly variable regions in the envelope protein and nonstructural 5A protein. HCV possesses seven major genotypes, among which genotype 1 is the most prevalent globally. The distribution of HCV genotypes varies based on geography, and each genotype has a different sensitivity to interferon treatment. Recently-developed direct-acting antivirals (DAAs), which target viral proteases or polymerases, mediate drastically better antiviral effects than previous therapeutics. Although treatment with DAAs has led to the development of drug-resistant HCV mutants, the most recently approved DAAs show improved pan-genomic activity, with a higher barrier to viral resistance.

Treatment-associated polymorphisms in protease are significantly associated with higher viral load and lower CD4 count in newly diagnosed drug-naive HIV-1 infected patients

NARCIS (Netherlands)

K. Theys (Kristof); K. Deforche; J. Vercauteren (Jurgen); P. Libin (Pieter); D.A.M.C. van de Vijver (David); J. Albert (Jan); B. Åsjö (Birgitta); M. Bruckova (Marie); R.J. Camacho (Ricardo Jorge); B. Clotet (Bonaventura); Z. Grossman (Zehava); A. Horban (Andrzej); C. Kücherer (Claudia); D. Paraskevis (Dimitrios); E. Puchhammer-Stöckl (Elisabeth); C. Riva (Chiara); L. Ruiz (Lidia); J.-C. Schmit (Jean-Claude); R. Schuurman (Rob); A. Sonnerborg (Anders); D. Stanekova (Danica); D. Struck (Daniel); K. van Laethem (Kristel); A.M.J. Wensing (Annemarie); E. Puchhammer-Stockl E. (Elisabeth); M. Sarcletti (M.); B. Schmied (B.); M. Geit (M.); G. Balluch (G.); A.M. Vandamme (Anne Mieke); I. Derdelinck (Inge); A. Sasse (A.); M. Bogaert (M.); H. Ceunen (H.); A. de Roo (Annie); M. De Wit (Meike); F. Echahidi (F.); K. Fransen (K.); J.-C. Goffard (J.); P. Goubau (Patrick); E. Goudeseune (E.); J.-C. Yombi (J.); P. Lacor (Patrick); C. Liesnard (C.); M. Moutschen (M.); L.A. Pierard; R. Rens (R.); J. Schrooten; D. Vaira (D.); A. van den Heuvel (A.); B. van der Gucht (B.); M. van Ranst (Marc); E. van Wijngaerden (Eric); T. Vandercam; M. Vekemans (M.); C. Verhofstede; N. Clumeck (N.); K. van Laethem (K.); L.G. Kostrikis (Leondios); I. Demetriades (I.); I. Kousiappa (Ioanna); V.L. Demetriou (Victoria); J. Hezka (Johana); M. Linka (Marek); L. Machala (L.); L.B. Jrgensen (L.); J. Gerstoft (J.); L. Mathiesen (L.); C. Pedersen (Court); C. Nielsen (Claus); A. Laursen (A.); B. Kvinesdal (B.); K. Liitsola (Kirsi); M. Ristola (M.); J. Suni (J.); J. Sutinen (J.); K. Korn (Klaus); C. K̈ucherer (C.); P. Braun (P.); G. Poggensee (G.); M. Däumer (M.); D. Eberle (David); O. Hamouda (Osamah); H. Heiken (H.); R. Kaiser (Rolf); H. Knechten (H.); H. M̈uller (H.); S. Neifer (S.); H. Walter (Hauke); B. Gunsenheimer-Bartmeyer (B.); T. Harrer (T.); A. Hatzakis (Angelos); E. Hatzitheodorou (E.); C. Issaris (C.); C. Haida (C.); A. Zavitsanou (A.); G. Magiorkinis (Gkikas); M. Lazanas (M.); L. Chini; N. Magafas (N.); N. Tsogas (N.); V. Paparizos (V.); S. Kourkounti (S.); A. Antoniadou (A.); A. Papadopoulos (A.); P. Panagopoulos (P.); G. Poulakou (G.); V. Sakka (V.); G. Chryssos (G.); S. Drimis (S.); P. Gargalianos (P.); M. Lelekis (M.); G. Xilomenos (G.); M. Psichogiou (M.); G.L. Daikos (George); G. Panos (G.); G. Haratsis (G.); T. Kordossis (T.); A. Kontos (Angelos); G. Koratzanis (G.); M. Theodoridou (M.); G. Mostrou (G.); V. Spoulou (V.); W. Hall (W.); C. de Gascun (Cillian); C. Byrne (C.); M. Duffy (M.); P. Bergin; D. Reidy (D.); G. Farrell; J. Lambert (Julien); E. O'Connor (E.); A. Rochford (A.); J. Low (J.); P. Coakely (P.); S. Coughlan (Suzie); I. Levi (I.); D. Chemtob (D.); C. Balotta (Claudia); C. Mussini (C.); I. Caramma (I.); A. Capetti (A.); M.C. Colombo (M.); C. Rossi (Cesare); F. Prati (Francesco); F. Tramuto (F.); F. Vitale (F.); M. Ciccozzi (M.); G. Angarano (Guiseppe); G. Rezza (G.); R. Hemmer (R.); V. Arendt (V.); T. Staub (T.); F. Schneider (F.); F. Roman (Francois); C.A.B. Boucher (Charles); P.H.M. van Bentum (P. H M); K. Brinkman (Kees); E.L.M. Op de Coul (Eline); M.E. van der Ende (Marchina); I.M. Hoepelman (Ilja Mohandas); M.E.E. van Kasteren (Marjo); J. Juttmann (Job); M. Kuipers (M.); N. Langebeek (Nienke); C. Richter (C.); R.M.W.J. Santegoets (R. M W J); L. Schrijnders-Gudde (L.); R. Schuurman (Rob); B.J.M. van de Ven (B. J M); B. Asjö (Birgitta); V. Ormaasen (Vidar); P. Aavitsland (P.); J. Stanczak (J.); G.P. Stanczak (G.); E. Firlag-Burkacka (E.); A. Wiercinska-Drapalo (A.); E. Jablonowska (E.); E. Malolepsza (E.); M. Leszczyszyn-Pynka (M.); W. Szata (W.); A. de Palma (Andre); F. Borges (F.); T. Paix̃ao (T.); V. Duque (V.); F. Aráujo (F.); M. Stanojevic (Maja); D.J. Jevtovic (D.); D. Salemovic (D.); M. Habekova (M.); M. Mokras (M.); P. Truska (P.); M. Poljak (Mario); D.Z. Babic (Dunja); J. Tomazic (J.); S. Vidmar (Suzanna); P. Karner (P.); C. Gutíerrez (C.); C. deMendoza (C.); I. Erkicia (I.); P. Domingo (P.); X. Camino (X.); M.A. Galindo (Miguel Angel); J.L. Blanco (J.); M. Leal (M.); A. Masabeu (A.); A. Guelar (A.); J.M. Llibre (Josep M.); N. Margall (N.); C. Iribarren (Carlos); S. Gutierrez (S.); J.F. Baldov́i (J.); C.E. Pedreira (Carlos Eduardo); J.M. Gatell (J.); S. Moreno (S.); C. de Mendoza (Carmen); V. Soriano (Virtudes); A. Blaxhult (A.); A. Heidarian (A.); A. Karlsson (A.); K. Aperia-Peipke (K.); I.-M. Bergbrant (I.); M. Gissĺen (M.); M. Svennerholm (M.); P. Bj̈orkman (P.); G. Bratt (G.); M. Carlsson (M.); H. Ekvall (H.); M. Ericsson (M.); M. Ḧofer (M.); B. Johansson (Bert); N. Kuylenstierna (N.); K. Ljungberg (Karl); S. Mäkitalo (S.); A. Strand; K. Öberg (Kjell); T. Berg (Trine)

2012-01-01

textabstractBackground: The effect of drug resistance transmission on disease progression in the newly infected patient is not well understood. Major drug resistance mutations severely impair viral fitness in a drug free environment, and therefore are expected to revert quickly. Compensatory

Hepatitis A virus cellular receptor 2 (HAVCR2) is decreased with viral infection and regulates pro-labour mediators OA.

Science.gov (United States)

Liong, Stella; Lim, Ratana; Barker, Gillian; Lappas, Martha

2017-07-01

Intrauterine infection caused by viral infection has been implicated to contribute to preterm birth. Hepatitis A virus cellular receptor 2 (HAVCR2) regulates inflammation in non-gestational tissues in response to viral infection. The aims of this study were to determine the effect of: (i) viral dsRNA analogue polyinosinic:polycytidylic acid (poly(I:C)) on HAVCR2 expression; and (ii) HAVCR2 silencing by siRNA (siHAVCR2) in primary amnion and myometrial cells on poly(I:C)-induced inflammation. In human foetal membranes and myometrium, HAVCR2 mRNA and protein expression was decreased when exposed to poly(I:C). Treatment of primary amnion and myometrial cells with poly(I:C) significantly increased the expression and release of pro-inflammatory cytokines TNF, IL1A, IL1B and IL6; the expression of chemokines CXCL8 and CCL2; the expression and secretion of adhesion molecules ICAM1 and VCAM1; and PTGS2 and PTGFR mRNA expression and the release of prostaglandin PGF 2α . This increase was significantly augmented in cells transfected with siHAVCR2. Furthermore, mRNA expression of anti-inflammatory cytokines IL4 and IL10 was significantly decreased. Collectively, our data suggest that HAVCR2 regulates cytokines, chemokines, prostaglandins and cell adhesion molecules in the presence of viral infection. This suggests a potential for HAVCR2 activators as therapeutics for the management of preterm birth associated with viral infections. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Viral Infections in Pregnancy: A Focus on Ebola Virus.

Science.gov (United States)

Olgun, Nicole S

2018-01-30

During gestation, the immune response of the placenta to viruses and other pathogens plays an important role in determining a pregnant woman's vulnerability toward infectious diseases. Located at the maternal- fetal interface, trophoblast cells serve to minimize the spread of viruses between the host and developing fetus through an intricate system of innate antiviral immune signaling. Adverse pregnancy outcomes, ranging from learning disabilities to preterm birth and fetal death, are all documented results of a viral breach in the placental barrier. Viral infections during pregnancy can also be spread through blood and vaginal secretions, and during the post-natal period, via breast milk. Thus, even in the absence of vertical transmission of viral infection to the fetus, maternal health can still be compromised and threaten the pregnancy. The most common viral DNA isolates found in gestation are adenovirus, cytomegalovirus, and enterovirus. However, with the recent pandemic of Ebola virus, and the first documented case of a neonate to survive due to experimental therapies in 2017, it is becoming increasingly apparent that the changing roles and impacts of viral infection during pregnancy needs to be better understood, while strategies to minimize adverse pregnancy outcomes need to be identified. This review focuses on the adverse impacts of viral infection during gestation, with an emphasis on Ebola virus. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Nanotip analysis for dielectrophoretic concentration of nanosized viral particles.

Science.gov (United States)

Yeo, Woon-Hong; Lee, Hyun-Boo; Kim, Jong-Hoon; Lee, Kyong-Hoon; Chung, Jae-Hyun

2013-05-10

Rapid and sensitive detection of low-abundance viral particles is strongly demanded in health care, environmental control, military defense, and homeland security. Current detection methods, however, lack either assay speed or sensitivity, mainly due to the nanosized viral particles. In this paper, we compare a dendritic, multi-terminal nanotip ('dendritic nanotip') with a single terminal nanotip ('single nanotip') for dielectrophoretic (DEP) concentration of viral particles. The numerical computation studies the concentration efficiency of viral particles ranging from 25 to 100 nm in radius for both nanotips. With DEP and Brownian motion considered, when the particle radius decreases by two times, the concentration time for both nanotips increases by 4-5 times. In the computational study, a dendritic nanotip shows about 1.5 times faster concentration than a single nanotip for the viral particles because the dendritic structure increases the DEP-effective area to overcome the Brownian motion. For the qualitative support of the numerical results, the comparison experiment of a dendritic nanotip and a single nanotip is conducted. Under 1 min of concentration time, a dendritic nanotip shows a higher sensitivity than a single nanotip. When the concentration time is 5 min, the sensitivity of a dendritic nanotip for T7 phage is 10(4) particles ml(-1). The dendritic nanotip-based concentrator has the potential for rapid identification of viral particles.

Nanotip analysis for dielectrophoretic concentration of nanosized viral particles

International Nuclear Information System (INIS)

Yeo, Woon-Hong; Lee, Hyun-Boo; Kim, Jong-Hoon; Chung, Jae-Hyun; Lee, Kyong-Hoon

2013-01-01

Rapid and sensitive detection of low-abundance viral particles is strongly demanded in health care, environmental control, military defense, and homeland security. Current detection methods, however, lack either assay speed or sensitivity, mainly due to the nanosized viral particles. In this paper, we compare a dendritic, multi-terminal nanotip (‘dendritic nanotip’) with a single terminal nanotip (‘single nanotip’) for dielectrophoretic (DEP) concentration of viral particles. The numerical computation studies the concentration efficiency of viral particles ranging from 25 to 100 nm in radius for both nanotips. With DEP and Brownian motion considered, when the particle radius decreases by two times, the concentration time for both nanotips increases by 4–5 times. In the computational study, a dendritic nanotip shows about 1.5 times faster concentration than a single nanotip for the viral particles because the dendritic structure increases the DEP-effective area to overcome the Brownian motion. For the qualitative support of the numerical results, the comparison experiment of a dendritic nanotip and a single nanotip is conducted. Under 1 min of concentration time, a dendritic nanotip shows a higher sensitivity than a single nanotip. When the concentration time is 5 min, the sensitivity of a dendritic nanotip for T7 phage is 10 4 particles ml −1 . The dendritic nanotip-based concentrator has the potential for rapid identification of viral particles. (paper)

THE POPULATION IMPACT OF ELIMINATING HOMELESSNESS ON HIV VIRAL SUPPRESSION AMONG PEOPLE WHO USE DRUGS

Science.gov (United States)

Marshall, Brandon D.L.; Elston, Beth; Dobrer, Sabina; Parashar, Surita; Hogg, Robert S.; Montaner, Julio S.G.; Kerr, Thomas; Wood, Evan; Milloy, M-J

2015-01-01

Objective We sought to estimate the change in viral suppression prevalence if homelessness were eliminated from a population of HIV-infected people who use drugs (PWUD). Design Community-recruited prospective cohort of HIV-infected PWUD in Vancouver, Canada. Behavioral information was collected at baseline and linked to a province-wide HIV/AIDS treatment database. The primary outcome was viral suppression (<50 copies/mL) measured during subsequent routine clinical care. Methods We employed an imputation-based marginal modelling approach. First, we used modified Poisson regression to obtain effect estimates (adjusting for sociodemographics, substance use, addiction treatment, and other confounders). Then, we imputed an outcome probability for each individual while manipulating the exposure (homelessness). Population viral suppression prevalence under realized and “housed” scenarios were obtained by averaging these probabilities across the population. Bootstrapping was conducted to calculate 95% confidence limits. Results Of 706 individuals interviewed between January 2005 and December 2015, the majority was male (66.0%), of Caucasian race/ethnicity (55.1%), and had a history of injection (93.6%). At first study visit, 223 (31.6%) reported recent homelessness, and 37.8% were subsequently identified as virally suppressed. Adjusted marginal models estimated a 15.1% relative increase (95%CI: 9.0%, 21.7%) in viral suppression in the entire population—to 43.5% (95%CI: 39.4%, 48.2%)—if all homeless individuals were housed. Among those homeless, eliminating this exposure would increase viral suppression from 22.0% to 40.1% (95%CI: 35.1%, 46.1%), an 82.3% relative increase. Conclusions Interventions to house homeless, HIV-positive individuals who use drugs could significantly increase population viral suppression. Such interventions should be implemented as a part of renewed HIV/AIDS prevention and treatment efforts. PMID:26636924

Viral diseases in honey bee queens

DEFF Research Database (Denmark)

Francis, Roy Mathew

Honey bees are important insects for human welfare, due to pollination as well as honey production. Viral diseases strongly impact honey bee health, especially since the spread of varroa mites. This dissertation deals with the interactions between honey bees, viruses and varroa mites. A new tool...... was developed to diagnose three viruses in honey bees. Quantitative PCR was used to investigate the distribution of two popular viruses in five different tissues of 86 honey bee queens. Seasonal variation of viral infection in honey bee workers and varroa mites were determined by sampling 23 colonies under...

Viral infections as controlling factors for the deep biosphere? (Invited)

Science.gov (United States)

Engelen, B.; Engelhardt, T.; Sahlberg, M.; Cypionka, H.

2009-12-01

The marine deep biosphere represents the largest biotope on Earth. Throughout the last years, we have obtained interesting insights into its microbial community composition. However, one component that was completely overlooked so far is the viral inventory of deep-subsurface sediments. While viral infections were identified to have a major impact on the benthic microflora of deep-sea surface sediments (Danavaro et al. 2008), no studies were performed on deep-biosphere samples, so far. As grazers probably play only a minor role in anoxic and highly compressed deep sediments, viruses might be the main “predators” for indigenous microorganisms. Furthermore, the release of cell components, called “the viral shunt”, could have a major impact on the deep biosphere in providing labile organic compounds to non-infected microorganisms in these generally nutrient depleted sediments. However, direct counting of viruses in sediments is highly challenging due to the small size of viruses and the high background of small particles. Even molecular surveys using “universal” PCR primers that target phage-specific genes fail due to the vast phage diversity. One solution for this problem is the lysogenic viral life cycle as many bacteriophages integrate their DNA into the host genome. It is estimated that up to 70% of cultivated bacteria contain prophages within their genome. Therefore, culture collections (Batzke et al. 2007) represent an archive of the viral composition within the respective habitat. These prophages can be induced to become free phage particles in stimulation experiments in which the host cells are set under certain stress situations such as a treatment with UV exposure or DNA-damaging antibiotics. The study of the viral component within the deep biosphere offers to answer the following questions: To which extent are deep-biosphere populations controlled by viral infections? What is the inter- and intra-specific diversity and the host-specific viral

Flavonoids: promising natural compounds against viral infections.

Science.gov (United States)

Zakaryan, Hovakim; Arabyan, Erik; Oo, Adrian; Zandi, Keivan

2017-09-01

Flavonoids are widely distributed as secondary metabolites produced by plants and play important roles in plant physiology, having a variety of potential biological benefits such as antioxidant, anti-inflammatory, anticancer, antibacterial, antifungal and antiviral activity. Different flavonoids have been investigated for their potential antiviral activities and several of them exhibited significant antiviral properties in in vitro and even in vivo studies. This review summarizes the evidence for antiviral activity of different flavonoids, highlighting, where investigated, the cellular and molecular mechanisms of action on viruses. We also present future perspectives on therapeutic applications of flavonoids against viral infections.

Treating viral hemorrhagic fever.

NARCIS (Netherlands)

Mairuhu, A.T.; Brandjes, D.P.; Gorp, E. van

2003-01-01

Viral hemorrhagic fevers are illnesses associated with a number of geographically restricted, mostly tropical areas. Over recent decades a number of new hemorrhagic fever viruses have emerged. Advances in our understanding of the pathophysiology of these diseases have improved our initial supportive

Environmental drivers of viral community composition in Antarctic soils identified by viromics.

Science.gov (United States)

Adriaenssens, Evelien M; Kramer, Rolf; Van Goethem, Marc W; Makhalanyane, Thulani P; Hogg, Ian; Cowan, Don A

2017-07-19

The Antarctic continent is considered the coldest and driest place on earth with simple ecosystems, devoid of higher plants. Soils in the ice-free regions of Antarctica are known to harbor a wide range of microorganisms from primary producers to grazers, yet their ecology and particularly the role of viruses is poorly understood. In this study, we examined the virus community structures of 14 soil samples from the Mackay Glacier region. Viral communities were extracted from soil and the dsDNA was extracted, amplified using single-primer amplification, and sequenced using the Ion Torrent Proton platform. Metadata on soil physico-chemistry was collected from all sites. Both read and contig datasets were analyzed with reference-independent and reference-dependent methods to assess viral community structures and the influence of environmental parameters on their distribution. We observed a high heterogeneity in virus signatures, independent of geographical proximity. Tailed bacteriophages were dominant in all samples, but the incidences of the affiliated families Siphoviridae and Myoviridae were inversely correlated, suggesting direct competition for hosts. Viruses of the families Phycodnaviridae and Mimiviridae were present at significant levels in high-diversity soil samples and were found to co-occur, implying little competition between them. Combinations of soil factors, including pH, calcium content, and site altitude, were found to be the main drivers of viral community structure. The pattern of viral community structure with higher levels of diversity at lower altitude and pH, and co-occurring viral families, suggests that these cold desert soil viruses interact with each other, the host, and the environment in an intricate manner, playing a potentially crucial role in maintaining host diversity and functioning of the microbial ecosystem in the extreme environments of Antarctic soil.

Viral impacts on microbial carbon cycling in thawing permafrost soils

Science.gov (United States)

Trubl, G. G.; Roux, S.; Bolduc, B.; Jang, H. B.; Emerson, J. B.; Solonenko, N.; Li, F.; Solden, L. M.; Vik, D. R.; Wrighton, K. C.; Saleska, S. R.; Sullivan, M. B.; Rich, V. I.

2017-12-01

Permafrost contains 30-50% of global soil carbon (C) and is rapidly thawing. While the fate of this C is unknown, it will be shaped in part by microbes and their associated viruses, which modulate host activities via mortality and metabolic control. To date, viral research in soils has been outpaced by that in aquatic environments, due to the technical challenges of accessing viruses as well as the dramatic physicochemical heterogeneity in soils. Here, we describe advances in soil viromics from our research on permafrost-associated soils, and their implications for associated terrestrial C cycling. First, we optimized viral resuspension-DNA extraction methods for a range of soil types. Second, we applied cutting-edge viral-specific informatics methods to recover viral populations, define their gene content, connect them to potential hosts, and analyze their relationships to environmental parameters. A total of 781 viral populations were recovered from size-fractionated virus samples of three soils along a permafrost thaw gradient. Ecological analyses revealed endemism as recovered viral populations were largely unique to each habitat and unlike those in aquatic communities. Genome- and network-based classification assigned these viruses into 226 viral clusters (VCs; genus-level taxonomy), 55% of which were novel. This increases the number of VCs by a third and triples the number of soil viral populations in the RefSeq database (currently contains 256 VCs and 316 soil viral populations). Genomic analyses revealed 85% of the genes were functionally unknown, though 5% of the annotatable genes contained C-related auxiliary metabolic genes (AMGs; e.g. glycoside hydrolases). Using sequence-based features and microbial population genomes, we were able to in silico predict hosts for 30% of the viral populations. The identified hosts spanned 3 phyla and 6 genera but suggested these viruses have species-specific host ranges as >80% of hosts for a given virus were in the same

The Immunoproteasome and Viral Infection: A Complex Regulator of Inflammation

Directory of Open Access Journals (Sweden)

Mary Katherine McCarthy

2015-01-01

Full Text Available During viral infection, proper regulation of immune responses is necessary to ensure successful viral clearance with minimal host tissue damage. Proteasomes play a crucial role in the generation of antigenic peptides for presentation on MHC class I molecules, and thus activation of CD8 T cells, as well as activation of the NF-kB pathway. A specialized type of proteasome called the immunoproteasome is constitutively expressed in hematopoietic cells and induced in nonimmune cells during viral infection by interferon (IFN signaling. The immunoproteasome regulates CD8 T cell responses to many viral epitopes during infection. Accumulating evidence suggests that the immunoproteasome may also contribute to regulation of proinflammatory cytokine production, activation of the NF-kB pathway, and management of oxidative stress. Many viruses have mechanisms of interfering with immunoproteasome function, including prevention of transcriptional upregulation of immunoproteasome components as well as direct interaction of viral proteins with immunoproteasome subunits. A better understanding of the role of the immunoproteasome in different cell types, tissues, and hosts has the potential to improve vaccine design and facilitate the development of effective treatment strategies for viral infections.

Attitudinal Factors Affecting Viral Advertising Pass-On Behaviour of Online Consumers in Food Industry

Science.gov (United States)

Mohd Salleh, Nurhidayah; Ariff, Mohd Shoki Md; Zakuan, Norhayati; Sulaiman, Zuraidah; Zameri Mat Saman, Muhamad

2016-05-01

The increase number of active users of social media, especially Facebook, stimulates viral advertising behaviour among them, thus attracting e-marketers to focus on viral advertising in promoting their products. In global market, use of Facebook platform indicated that food services/restaurant of food industry is ranked number 11 with 18.8% users’ response rate within the platform. This development calls for e-marketers in Malaysia to use Facebook as their viral advertising channel. Attitudinal factors affecting the viral advertising pass-on behaviour (VAPB) especially among members of social media is of interest to many researchers. The typical attitudinal factors used were attitude toward social media (ATSM), attitude toward advertising in social media (AASM) and attitude toward advertising in general (AAIG). Attitude toward advertised brand (ATAB) is important in fast food industry because users of social media tend to share their experience about tastes and features of the food. However, ATAB is less emphasized in the conceptual model between attitudinal factors and VAPB. These four factors of consumer attitude served as independent variables in the conceptual model of this study and their effect on viral advertising pass-on behaviour among members of Domino's Pizza Malaysia Facebook page was examined. Online survey using a set of questionnaire which was sent to the members of this group via private message was employed. A total of 254 sets of usable questionnaires were collected from the respondents. All the attitudinal factors, except for AASM, were found to have positive and significant effect on VAPB. AAIG exerted the strongest effect on VAPB. Therefore, e-marketers should emphasize on developing a favourable attitude toward advertising in general among members of a social media to get them involve in viral advertising. In addition, instilling a favourable attitude towards advertised brand is also vital as it influences the members to viral the brand

Sonographic changes of liver and gallbladder in acute viral hepatitis

Directory of Open Access Journals (Sweden)

Ebrahimi Daryani N

2001-07-01

Full Text Available Hepatomegaly, decrease in the liver paranchymal echo and increase in the gallbladder wall thickness has been shown in acute viral hepatitis. The present study was done to determine sonographic changes in acute viral hepatitis. We performed liver and bile ducts sonography and specific tests on 42 patients (mean age: 31.5 and 61% male with acute viral hepatitis. Gallbladder wall thickness was seen in 45.2% and hepatomegaly in 33.3% of patients and liver paranchymal echo was decreased in 19.3%. Age, sex, type of hepatitis, cholecystitis like symptoms, aspartate aminotransfrase, alanine aminotransfrase, alkaline phosphatase and bilirubin did not significantly corralate with these changes. Only raised prothrombin time was strongly correlated to the thickening of the gallbladder and decrease in the liver paranchymal echo and cholesistic like symptoms we can postulate that thickening of the gallbladder and decrease in the liver paranchymal echo is not dependent on the severity and speed of the paranchymal necrosis (as considered with ALT and AST but they depend on the liver function disturbance (as considered with PT because the thickening of the gall bladder is present in 45% of the patients and 10% of the normal population have gallbladder stones, one should not perform the diagnosis of acute cholecystitis, only on the basis of sonographic report without attention to the clinical and laboratory data.

Disparities in HIV/AIDS, Viral Hepatitis, STDs, and TB

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... Search The CDC Health Disparities in HIV/AIDS, Viral Hepatitis, STDs, and TB Note: Javascript is disabled or ... Other Pacific Islanders MMWR Publications HIV and AIDS Viral Hepatitis STDs Tuberculosis Training and Networking Resources Call for ...

Intracellular Crosslinking of Filoviral Nucleoproteins with Xintrabodies Restricts Viral Packaging

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Tamarand Lee Darling

2017-09-01

Full Text Available Viruses assemble large macromolecular repeat structures that become part of the infectious particles or virions. Ribonucleocapsids (RNCs of negative strand RNA viruses are a prime example where repetition of nucleoprotein (NP along the genome creates a core polymeric helical scaffold that accommodates other nucleocapsid proteins including viral polymerase. The RNCs are transported through the cytosol for packaging into virions through association with viral matrix proteins at cell membranes. We hypothesized that RNC would be ideal targets for crosslinkers engineered to promote aberrant protein–protein interactions, thereby blocking their orderly transport and packaging. Previously, we had generated single-domain antibodies (sdAbs against Filoviruses that have all targeted highly conserved C-terminal regions of NP known to be repetitively exposed along the length of the RNCs of Marburgvirus (MARV and Ebolavirus (EBOV. Our crosslinker design consisted of dimeric sdAb expressed intracellularly, which we call Xintrabodies (X- for crosslinking. Electron microscopy of purified NP polymers incubated with purified sdAb constructs showed NP aggregation occurred in a genus-specific manner with dimeric and not monomeric sdAb. A virus-like particle (VLP assay was used for initial evaluation where we found that dimeric sdAb inhibited NP incorporation into VP40-based VLPs whereas monomeric sdAb did not. Inhibition of NP packaging was genus specific. Confocal microscopy revealed dimeric sdAb was diffuse when expressed alone but focused on pools of NP when the two were coexpressed, while monomeric sdAb showed ambivalent partition. Infection of stable Vero cell lines expressing dimeric sdAb specific for either MARV or EBOV NP resulted in smaller plaques and reduced progeny of cognate virus relative to wild-type Vero cells. Though the impact was marginal at later time-points, the collective data suggest that viral replication can be reduced by crosslinking

[History of viral hepatitis].

Science.gov (United States)

Fonseca, José Carlos Ferraz da

2010-01-01

The history of viral hepatitis goes back thousands of years and is a fascinating one. When humans were first infected by such agents, a natural repetitive cycle began, with the capacity to infect billions of humans, thus decimating the population and causing sequelae in thousands of lives. This article reviews the available scientific information on the history of viral hepatitis. All the information was obtained through extensive bibliographic review, including original and review articles and consultations on the internet. There are reports on outbreaks of jaundice epidemics in China 5,000 years ago and in Babylon more than 2,500 years ago. The catastrophic history of great jaundice epidemics and pandemics is well known and generally associated with major wars. In the American Civil War, 40,000 cases occurred among Union troops. In 1885, an outbreak of catarrhal jaundice affected 191 workers at the Bremen shipyard (Germany) after vaccination against smallpox. In 1942, 28,585 soldiers became infected with hepatitis after inoculation with the yellow fever vaccine. The number of cases of hepatitis during the Second World War was estimated to be 16 million. Only in the twentieth century were the main agents causing viral hepatitis identified. The hepatitis B virus was the first to be discovered. In this paper, through reviewing the history of major epidemics caused by hepatitis viruses and the history of discovery of these agents, singular peculiarities were revealed. Examples of this include the accidental or chance discovery of the hepatitis B and D viruses.

Serum hepatitis B surface antigen and hepatitis B e antigen titers: disease phase influences correlation with viral load and intrahepatic hepatitis B virus markers.

Science.gov (United States)

Thompson, Alexander J V; Nguyen, Tin; Iser, David; Ayres, Anna; Jackson, Kathy; Littlejohn, Margaret; Slavin, John; Bowden, Scott; Gane, Edward J; Abbott, William; Lau, George K K; Lewin, Sharon R; Visvanathan, Kumar; Desmond, Paul V; Locarnini, Stephen A

2010-06-01

Although threshold levels for hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) titers have recently been proposed to guide therapy for chronic hepatitis B (CHB), their relationship to circulating hepatitis B virus (HBV) DNA and intrahepatic HBV replicative intermediates, and the significance of emerging viral variants, remains unclear. We therefore tested the hypothesis that HBsAg and HBeAg titers may vary independently of viral replication in vivo. In all, 149 treatment-naïve CHB patients were recruited (HBeAg-positive, n = 71; HBeAg-negative, n = 78). Quantification of HBeAg and HBsAg was performed by enzyme immunoassay. Virological characterization included serum HBV DNA load, HBV genotype, basal core promoter (BCP)/precore (PC) sequence, and, in a subset (n = 44), measurement of intrahepatic covalently closed circular DNA (cccDNA) and total HBV DNA, as well as quantitative immunohistochemical (IHC) staining for HBsAg. In HBeAg-positive CHB, HBsAg was positively correlated with serum HBV DNA and intrahepatic cccDNA and total HBV DNA (r = 0.69, 0.71, 0.76, P < 0.01). HBeAg correlated with serum HBV DNA (r = 0.60, P < 0.0001), although emerging BCP/PC variants reduced HBeAg titer independent of viral replication. In HBeAg-negative CHB, HBsAg correlated poorly with serum HBV DNA (r = 0.28, P = 0.01) and did not correlate with intrahepatic cccDNA nor total HBV DNA. Quantitative IHC for hepatocyte HBsAg confirmed a relationship with viral replication only in HBeAg-positive patients. The correlation between quantitative HBsAg titer and serum and intrahepatic markers of HBV replication differs between patients with HBeAg-positive and HBeAg-negative CHB. HBeAg titers may fall independent of viral replication as HBeAg-defective variants emerge prior to HBeAg seroconversion. These findings provide new insights into viral pathogenesis and have practical implications for the use of quantitative serology as a clinical biomarker.

Hepatitis C Virus: Viral Quasispecies and Genotypes

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Kyoko Tsukiyama-Kohara

2017-12-01

Full Text Available Hepatitis C virus (HCV mainly replicates in the cytoplasm, where it easily establishes persistent infection, resulting in chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Due to its high rate of mutation, HCV forms viral quasispecies, categorized based on the highly variable regions in the envelope protein and nonstructural 5A protein. HCV possesses seven major genotypes, among which genotype 1 is the most prevalent globally. The distribution of HCV genotypes varies based on geography, and each genotype has a different sensitivity to interferon treatment. Recently-developed direct-acting antivirals (DAAs, which target viral proteases or polymerases, mediate drastically better antiviral effects than previous therapeutics. Although treatment with DAAs has led to the development of drug-resistant HCV mutants, the most recently approved DAAs show improved pan-genomic activity, with a higher barrier to viral resistance.

Biological species in the viral world.

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Bobay, Louis-Marie; Ochman, Howard

2018-06-05

Due to their dependence on cellular organisms for metabolism and replication, viruses are typically named and assigned to species according to their genome structure and the original host that they infect. But because viruses often infect multiple hosts and the numbers of distinct lineages within a host can be vast, their delineation into species is often dictated by arbitrary sequence thresholds, which are highly inconsistent across lineages. Here we apply an approach to determine the boundaries of viral species based on the detection of gene flow within populations, thereby defining viral species according to the biological species concept (BSC). Despite the potential for gene transfer between highly divergent genomes, viruses, like the cellular organisms they infect, assort into reproductively isolated groups and can be organized into biological species. This approach revealed that BSC-defined viral species are often congruent with the taxonomic partitioning based on shared gene contents and host tropism, and that bacteriophages can similarly be classified in biological species. These results open the possibility to use a single, universal definition of species that is applicable across cellular and acellular lifeforms.

[Viral respiratory co-infections in pediatric patients admitted for acute respiratory infection and their impact on clinical severity].

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Martínez, Pamela; Cordero, Jaime; Valverde, Cristián; Unanue, Nancy; Dalmazzo, Roberto; Piemonte, Paula; Vergara, Ivonne; Torres, Juan P

2012-04-01

Respiratory viruses are the leading cause of acute respiratory tract infection (ARI) in children. It has been reported that viral respiratory co-infection could be associated with severe clinical course. To describe the frequency of viral co-infection in children admitted for AlRI and evaluate whether this co-infection was associated with more severe clinical course. Prospective, descriptive study in pediatric patients who were hospitalized for ARI, with molecular detection of at least 1 respiratory virus in nasopharyngeal sample studied by PCR-Microarray for 17 respiratory viruses. 110 out of 147 patients with detection of > 1 respiratory virus were included. Viral co-infection was detected in 41/110 (37%). 22/110 children (20%) were classified as moderate to severe clinical course and 88/110 (80%) were classified as mild clinical course. In the group of moderate to severe clinical course, viral respiratory co-infection was detected in 6/22 (27.3%), compared to 35/88 (39.8 %) in the mild clinical course group. No statistically significant difference was found regarding the presence of co-infection between groups (p = 0.33). We detected high rates of viral co-infection in children with ARI. It was not possible to demonstrate that viral co-infections were related with severe clinical course in hospitalized children.

Dengue viral RNA levels in peripheral blood mononuclear cells are associated with disease severity and preexisting dengue immune status.

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Anon Srikiatkhachorn

Full Text Available Infection with dengue viruses (DENV causes a wide range of manifestations from asymptomatic infection to a febrile illness called dengue fever (DF, to dengue hemorrhagic fever (DHF. The in vivo targets of DENV and the relation between the viral burden in these cells and disease severity are not known.The levels of positive and negative strand viral RNA in peripheral blood monocytes, T/NK cells, and B cells and in plasma of DF and DHF cases were measured by quantitative RT-PCR.Positive strand viral RNA was detected in monocytes, T/NK cells and B cells with the highest amounts found in B cells. Viral RNA levels in CD14+ cells and plasma were significantly higher in DHF compared to DF, and in cases with a secondary infection compared to those undergoing a primary infection. The distribution of viral RNA among cell subpopulations was similar in DF and DHF cases. Small amounts of negative strand RNA were found in a few cases only. The severity of plasma leakage correlated with viral RNA levels in plasma and in CD14+ cells.B cells were the principal cells containing DENV RNA in peripheral blood, but overall there was little active DENV RNA replication detectable in peripheral blood mononuclear cells (PBMC. Secondary infection and DHF were associated with higher viral burden in PBMC populations, especially CD14+ monocytes, suggesting that viral infection of these cells may be involved in disease pathogenesis.

Human Parvovirus B19 Utilizes Cellular DNA Replication Machinery for Viral DNA Replication.

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Zou, Wei; Wang, Zekun; Xiong, Min; Chen, Aaron Yun; Xu, Peng; Ganaie, Safder S; Badawi, Yomna; Kleiboeker, Steve; Nishimune, Hiroshi; Ye, Shui Qing; Qiu, Jianming

2018-03-01

Human parvovirus B19 (B19V) infection of human erythroid progenitor cells (EPCs) induces a DNA damage response and cell cycle arrest at late S phase, which facilitates viral DNA replication. However, it is not clear exactly which cellular factors are employed by this single-stranded DNA virus. Here, we used microarrays to systematically analyze the dynamic transcriptome of EPCs infected with B19V. We found that DNA metabolism, DNA replication, DNA repair, DNA damage response, cell cycle, and cell cycle arrest pathways were significantly regulated after B19V infection. Confocal microscopy analyses revealed that most cellular DNA replication proteins were recruited to the centers of viral DNA replication, but not the DNA repair DNA polymerases. Our results suggest that DNA replication polymerase δ and polymerase α are responsible for B19V DNA replication by knocking down its expression in EPCs. We further showed that although RPA32 is essential for B19V DNA replication and the phosphorylated forms of RPA32 colocalized with the replicating viral genomes, RPA32 phosphorylation was not necessary for B19V DNA replication. Thus, this report provides evidence that B19V uses the cellular DNA replication machinery for viral DNA replication. IMPORTANCE Human parvovirus B19 (B19V) infection can cause transient aplastic crisis, persistent viremia, and pure red cell aplasia. In fetuses, B19V infection can result in nonimmune hydrops fetalis and fetal death. These clinical manifestations of B19V infection are a direct outcome of the death of human erythroid progenitors that host B19V replication. B19V infection induces a DNA damage response that is important for cell cycle arrest at late S phase. Here, we analyzed dynamic changes in cellular gene expression and found that DNA metabolic processes are tightly regulated during B19V infection. Although genes involved in cellular DNA replication were downregulated overall, the cellular DNA replication machinery was tightly

Porcine semen as a vector for transmission of viral pathogens.

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Maes, Dominiek; Van Soom, Ann; Appeltant, Ruth; Arsenakis, Ioannis; Nauwynck, Hans

2016-01-01

Different viruses have been detected in porcine semen. Some of them are on the list of the World Organization for Animal Health (OIE), and consequently, these pathogens are of socioeconomic and/or public health importance and are of major importance in the international trade of animals and animal products. Artificial insemination (AI) is one of the most commonly used assisted reproductive technologies in pig production worldwide. This extensive use has enabled pig producers to benefit from superior genetics at a lower cost compared to natural breeding. However, the broad distribution of processed semen doses for field AI has increased the risk of widespread transmission of swine viral pathogens. Contamination of semen can be due to infections of the boar or can occur during semen collection, processing, and storage. It can result in reduced semen quality, embryonic mortality, endometritis, and systemic infection and/or disease in the recipient female. The presence of viral pathogens in semen can be assessed by demonstration of viable virus, nucleic acid of virus, or indirectly by measuring serum antibodies in the boar. The best way to prevent disease transmission via the semen is to assure that the boars in AI centers are free from the disease, to enforce very strict biosecurity protocols, and to perform routine health monitoring of boars. Prevention of viral semen contamination should be the primary focus because it is easier to prevent contamination than to eliminate viruses once present in semen. Nevertheless, research and development of novel semen processing treatments such as single-layer centrifugation is ongoing and may allow in the future to decontaminate semen. Copyright © 2016 Elsevier Inc. All rights reserved.

Viral Immunotherapy to Eradicate Subclinical Brain Metastases

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2014-05-01

flash frozen brain tissue. Hoechst and CFSE labeled cells are readily visualized in fresh CSF. The brightest staining is achieved with Hoechst and is...viral infection in the meninges is in part due to reduction of the effects of suppressor macrophages. The work is complicated by the fact that...therapeutic effect of viral infection in the meninges is in part due to reduction of the effects of suppressor macrophages. • We found that mice cured

Multivalent display of proteins on viral nanoparticles using molecular recognition and chemical ligation strategies

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Venter, P. Arno; Dirksen, Anouk; Thomas, Diane; Manchester, Marianne; Dawson, Philip E.; Schneemann, Anette

2011-01-01

Multivalent display of heterologous proteins on viral nanoparticles forms a basis for numerous applications in nanotechnology, including vaccine development, targeted therapeutic delivery and tissue-specific bio-imaging. In many instances, precise placement of proteins is required for optimal functioning of the supramolecular assemblies, but orientation- and site-specific coupling of proteins to viral scaffolds remains a significant technical challenge. We have developed two strategies that allow for controlled attachment of a variety of proteins on viral particles using covalent and noncovalent principles. In one strategy, an interaction between domain 4 of anthrax protective antigen and its receptor was used to display multiple copies of a target protein on virus-like particles. In the other, expressed protein ligation and aniline-catalyzed oximation was used to covalently display a model protein. The latter strategy, in particular, yielded nanoparticles that induced potent immune responses to the coupled protein, suggesting potential applications in vaccine development. PMID:21545187

Antibody maturation and viral diversification in HIV-infected women.

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Maria M James

Full Text Available The Post-exposure Prophylaxis in Infants (PEPI-Malawi trial evaluated infant antiretroviral regimens for prevention of post-natal HIV transmission. A multi-assay algorithm (MAA that includes the BED capture immunoassay, an avidity assay, CD4 cell count, and viral load was used to identify women who were vs. were not recently infected at the time of enrollment (MAA recent, N = 73; MAA non-recent, N = 2,488; a subset of the women in the MAA non-recent group known to have been HIV infected for at least 2 years before enrollment (known non-recent, N = 54. Antibody maturation and viral diversification were examined in these women.Samples collected at enrollment (N = 2,561 and 12-24 months later (N = 1,306 were available for serologic analysis using the BED and avidity assays. A subset of those samples was used for analysis of viral diversity, which was performed using a high resolution melting (HRM diversity assay. Viral diversity analysis was performed using all available samples from women in the MAA recent group (61 enrollment samples, 38 follow-up samples and the known non-recent group (43 enrollment samples, 22 follow-up samples. Diversity data from PEPI-Malawi were also compared to similar data from 169 adults in the United States (US with known recent infection (N = 102 and known non-recent infection (N = 67.In PEPI-Malawi, results from the BED and avidity assays increased over time in the MAA recent group, but did not change significantly in the MAA non-recent group. At enrollment, HIV diversity was lower in the MAA recent group than in the known non-recent group. HRM diversity assay results from women in PEPI-Malawi were similar to those from adults in the US with known duration of HIV infection.Antibody maturation and HIV diversification patterns in African women provide additional support for use of the MAA to identify populations with recent HIV infection.

Information Overload and Viral Marketing: Countermeasures and Strategies

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Cheng, Jiesi; Sun, Aaron; Zeng, Daniel

Studying information diffusion through social networks has become an active research topic with important implications in viral marketing applications. One of the fundamental algorithmic problems related to viral marketing is the Influence Maximization (IM) problem: given an social network, which set of nodes should be considered by the viral marketer as the initial targets, in order to maximize the influence of the advertising message. In this work, we study the IM problem in an information-overloaded online social network. Information overload occurs when individuals receive more information than they can process, which can cause negative impacts on the overall marketing effectiveness. Many practical countermeasures have been proposed for alleviating the load of information on recipients. However, how these approaches can benefit viral marketers is not well understood. In our work, we have adapted the classic Information Cascade Model to incorporate information overload and study its countermeasures. Our results suggest that effective control of information overload has the potential to improve marketing effectiveness, but the targeting strategy should be re-designed in response to these countermeasures.

Aptamers in Diagnostics and Treatment of Viral Infections

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Tomasz Wandtke

2015-02-01

Full Text Available Aptamers are in vitro selected DNA or RNA molecules that are capable of binding a wide range of nucleic and non-nucleic acid molecules with high affinity and specificity. They have been conducted through the process known as SELEX (Systematic Evolution of Ligands by Exponential Enrichment. It serves to reach specificity and considerable affinity to target molecules, including those of viral origin, both proteins and nucleic acids. Properties of aptamers allow detecting virus infected cells or viruses themselves and make them competitive to monoclonal antibodies. Specific aptamers can be used to interfere in each stage of the viral replication cycle and also inhibit its penetration into cells. Many current studies have reported possible application of aptamers as a treatment or diagnostic tool in viral infections, e.g., HIV (Human Immunodeficiency Virus, HBV (Hepatitis B Virus, HCV (Hepatitis C Virus, SARS (Severe Acute Respiratory Syndrome, H5N1 avian influenza and recently spread Ebola. This review presents current developments of using aptamers in the diagnostics and treatment of viral diseases.

Viral Warts-A Clinico-Epidemiological Study

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Laxmisha Chandrashekar

2003-01-01

Full Text Available Although clinical criteria, laboratory diagnosis and treatment are well established, scanty attention has been paid to prevalence and pattern of viral warts in India. HIV is widely prevalent and its influence on the number and morphology of viral warts has not yet been studied in our setup. Hence, this study was undertaken. One hindered and forty four cases of viral warts were studied between September 2000 and June 2002 at the department of Dermatology and STD, JIPMER, Pondicherry. These included 81childeren and 63 adults. In Children, viral warts were most commonly seen in the age group of 10to14 years (41.9%, whereas in adults, the most commonly seen in the age 14to20 years (46.03%. The average age at presentation was 11.5 years. The male to female ratio was 2.2 to 1 in children and 1.8 to 1 in adults. Family history of warts was observed in 27.7% of the cases. In children, multiple site involvement (62.9% was more common than single site involvement. The most commonly involved site was hand in children as also in adults. In adults, single site involvement (66.6%was more common than multiple site involvement. The most common type of wart seen in both children and adults was the common wart. Twenty percent of the cases showed koebnerization. Four cases were found to be seropositive for HIV infection, who were adult with genital warts, but florid manifestations were not seen.

Bacterial–viral load and the immune response in stable and exacerbated COPD: significance and therapeutic prospects

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D’Anna SE

2016-03-01

Full Text Available Silvestro Ennio D’Anna,1 Bruno Balbi,2 Francesco Cappello,3,4 Mauro Carone,2 Antonino Di Stefano21Department of Rehabilitation, Cardiorespiratory Unit, Fondazione Istituto G. Giglio di Cefalù, 2Pneumology Unit and Laboratory of Cytoimmunopathology of Heart and Lung, Fondazione Salvatore Maugeri, IRCCS, Veruno (NO and Cassano delle Murge (BA, 3Human Anatomy Section, Department of Experimental Biomedicine and Clinical Neuroscience, University of Palermo, Palermo, Italy; 4Euro-Mediterranean Institute of Science and Technology, Palermo, ItalyAbstract: Chronic obstructive pulmonary disease (COPD is characterized by persistent airflow limitation and an abnormal inflammatory response of the lung. Bacteria and viruses are a major cause of COPD exacerbations and may contribute to COPD progression by perpetuating the inflammatory response in the airways. Bacterial variety diminishes with increasing COPD severity. Respiratory viruses can colonize the lower respiratory tract in stable COPD, altering the respiratory microbiome and facilitating secondary bacterial infections. In this review, we present the most updated information about the role of bacteria and viruses in stable and exacerbated COPD. In our opinion, to optimize therapeutic strategies, the dynamic events involving bacterial–viral infections and related immune response in COPD phenotypes need to be better clarified. Our paper would address these points that we consider of great importance for the clinical management of COPD.Keywords: COPD phenotype, biomarkers, exacerbations, severity of COPD, microbiome

HPV-16 viral load in oropharyngeal squamous cell carcinoma using digital PCR.

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Antonsson, Annika; Knight, Lani; Panizza, Benedict J; Porceddu, Sandro V; Emmett, Sarah; Whiteman, David C

2018-05-09

We did not identify any strong associations between HPV-16 viral load and any of the clinical or lifestyle factors. The epidemiology of oropharyngeal SCC is changing, with an increasing proportion of HPV-positive cases seen in the last decade. It is known that a high viral load is linked to the development of cervical cancer, the relation between viral load and oropharyngeal SCC is less clear. We sought to determine HPV-16 viral load in HPV-positive oropharyngeal SCCs using highly sensitive digital PCR and to identify clinical and lifestyle factors associated with viral load. We analysed 45 HPV-16 positive oropharyngeal SCCs diagnosed between 2013 and 2015. All patients completed a lifestyle questionnaire and clinical data were extracted from medical charts. Viral load was determined using digital PCR assays for HPV-L1 and RNAseP. We found large variations in HPV-16 viral load from 1 to 930 copies per cell (median 34 copies per cell).

The human adenovirus type 5 E1B 55 kDa protein obstructs inhibition of viral replication by type I interferon in normal human cells.