Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| preliminary crystallographic characterization of an rna helicase from kunjin virus. | kunjin virus is a member of the flavivirus genus and is an australian variant of west nile virus. the c-terminal domain of the kunjin virus ns3 protein displays helicase activity. the protein is thought to separate daughter and template rna strands, assisting the initiation of replication by unwinding rna secondary structure in the 3' nontranslated region. expression, purification and preliminary crystallographic characterization of the ns3 helicase domain are reported. it is shown that kunjin v ... | 2006 | 16946468 |
| detection of seroconversion to west nile virus, usutu virus and sindbis virus in uk sentinel chickens. | we previously reported evidence of west nile virus (wnv) circulation in uk birds, probably introduced by migratory birds from overseas. we now demonstrate wnv-specific seroconversion in sentinel chickens raised on an english farm. maternal neutralizing antibodies to wnv in hatchlings declined within three weeks. during the following months, healthy chickens developed wnv neutralizing antibodies that were confirmed by immunoblotting and indirect immunofluorescence tests using wnv antigens. the pr ... | 2006 | 16952307 |
| recombination and selection in the evolution of picornaviruses and other mammalian positive-stranded rna viruses. | picornaviridae are a large virus family causing widespread, often pathogenic infections in humans and other mammals. picornaviruses are genetically and antigenically highly diverse, with evidence for complex evolutionary histories in which recombination plays a major part. to investigate the nature of recombination and selection processes underlying the evolution of serotypes within different picornavirus genera, large-scale analysis of recombination frequencies and sites, segregation by serotyp ... | 2006 | 16956935 |
| greyhound meningoencephalitis: pcr-based detection methods highlight an absence of the most likely primary inducing agents. | greyhound meningoencephalitis is currently classified as a breed-associated idiopathic central nervous system inflammatory disorder. the non-suppurative inflammatory response can be distinguished from the other breed-associated disorders based on histopathology and lesion topography, however the nature of the response primarily suggests a viral infection. in the present study pcr and rt-pcr technologies were employed on frozen cerebral tissue from confirmed cases of meningoencephalitis to target ... | 2006 | 16962261 |
| flavivirus membrane fusion. | flavivirus membrane fusion is mediated by a class ii viral fusion protein, the major envelope protein e, and the fusion process is extremely fast and efficient. understanding of the underlying mechanisms has been advanced significantly by the determination of e protein structures in their pre- and post-fusion conformations and by the elucidation of the quarternary organization of e proteins in the viral envelope. in this review, these structural data are discussed in the context of functional an ... | 2006 | 16963734 |
| role of the yellow fever virus structural protein genes in viral dissemination from the aedes aegypti mosquito midgut. | live-attenuated virus vaccines are key components in controlling arboviral diseases, but they must not disseminate in or be transmitted by mosquito vectors. although the cycles in which many mosquito-borne viruses are transmitted are well understood, the role of viral genetics in these processes has not been fully elucidated. yellow fever virus (yfv) is an important arbovirus and the prototype member of the family flaviviridae. here, yfv was used in aedes aegypti mosquitoes as a model to investi ... | 2006 | 16963758 |
| inflammatory response in human tick-borne encephalitis: analysis of postmortem brain tissue. | in central european tick-borne encephalitis (tbe) mechanisms of tissue destruction are poorly understood. to evaluate the contribution of immunological mechanisms to tissue injury, the authors immunohistochemically analyzed paraffin-embedded autoptic brain tissue of 26 human tbe cases. in the parenchymal compartment, there was a predominance of macrophages/microglia and cytotoxic t cells. in addition, it was found that granzyme b-expressing lymphocytes were in close contact with tbe-expressing n ... | 2006 | 16966222 |
| [the risk of yellow fever in travellers]. | yellow fever is a tropical virus disease characterised by high fever, jaundice, heart and kidney failure, and haemorrhagic diathesis. the causative flavivirus is endemic in parts of tropical africa and south america and is transmitted among humans and primates by mosquitoes. the chance that an unvaccinated traveller to west africa will die of yellow fever is estimated at 1:650 to 1:5000 visitors per month of stay, depending on whether an epidemic occurs. vaccination with the attenuated yellow fe ... | 2006 | 16967591 |
| clinical features of 62 imported cases of dengue fever in japan. | to describe the clinical features of dengue cases in japan, a retrospective study was conducted on 62 laboratory-confirmed japanese dengue cases presented to tokyo metropolitan komagome hospital between 1985 and 2000. age distribution was from 18 to 62 years old (mean, 31.5 years). all cases were imported from abroad and diagnosed as dengue fever. clinical manifestations included fever (100%), headache (90%), and skin rash (82%). laboratory examinations revealed leukocytopenia (71%), thrombocyto ... | 2006 | 16968923 |
| translation of the flavivirus kunjin ns3 gene in cis but not its rna sequence or secondary structure is essential for efficient rna packaging. | our previous studies using trans-complementation analysis of kunjin virus (kun) full-length cdna clones harboring in-frame deletions in the ns3 gene demonstrated the inability of these defective complemented rnas to be packaged into virus particles (w. j. liu, p. l. sedlak, n. kondratieva, and a. a. khromykh, j. virol. 76:10766-10775). in this study we aimed to establish whether this requirement for ns3 in rna packaging is determined by the secondary rna structure of the ns3 gene or by the essen ... | 2006 | 16971441 |
| homology modeling and molecular dynamics study of west nile virus ns3 protease: a molecular basis for the catalytic activity increased by the ns2b cofactor. | the west nile virus (wnv) ns3 serine protease, which plays an important role in assembly of infective virion, is an attractive target for anti-wnv drug development. cofactors ns2b and ns4a increase the catalytic activity of ns3 in dengue virus and hepatitis c virus, respectively. recent studies on the wnv-ns3 characterize the catalytically active form of ns3 by tethering the 40-residue cofactor ns2b. it is suggested that ns2b is essential for the ns3 activity in wnv, while there is no informatio ... | 2006 | 16972281 |
| cryptic properties of a cluster of dominant flavivirus cross-reactive antigenic sites. | a number of flaviviruses are important human pathogens, including yellow fever, dengue, west nile, japanese encephalitis, and tick-borne encephalitis (tbe) viruses. infection with or immunization against any of these viruses induces a subset of antibodies that are broadly flavivirus cross-reactive but do not exhibit significant cross-neutralization. nevertheless, these antibodies can efficiently bind to the major envelope protein (e), which is the main target of neutralizing and protective antib ... | 2006 | 16973559 |
| site-directed antibodies against the stem region reveal low ph-induced conformational changes of the semliki forest virus fusion protein. | the e1 envelope protein of the alphavirus semliki forest virus (sfv) is a class ii fusion protein that mediates low ph-triggered membrane fusion during virus infection. like other class i and class ii fusion proteins, during fusion e1 inserts into the target membrane and rearranges to form a trimeric hairpin structure. the postfusion structures of the alphavirus and flavivirus fusion proteins suggest that the "stem" region connecting the fusion protein domain iii to the transmembrane domain inte ... | 2006 | 16973563 |
| flavivirus infection activates the xbp1 pathway of the unfolded protein response to cope with endoplasmic reticulum stress. | the unfolded protein response (upr) is a coordinated change in gene expression triggered by perturbations in functions of the endoplasmic reticulum (er). xbp1, a key transcription factor of the upr, is activated by an ire1-mediated splicing event, which results in a frameshift and encodes a protein with transcriptional activity. here, we report that xbp1 was activated during flaviviral infection, as evidenced by xbp1 mrna splicing and protein expression, as well as induction of the downstream ge ... | 2006 | 16987981 |
| crystal structure of the west nile virus envelope glycoprotein. | the envelope glycoprotein (e) of west nile virus (wnv) undergoes a conformational rearrangement triggered by low ph that results in a class ii fusion event required for viral entry. herein we present the 3.0-a crystal structure of the ectodomain of wnv e, which reveals insights into the flavivirus life cycle. we found that wnv e adopts a three-domain architecture that is shared by the e proteins from dengue and tick-borne encephalitis viruses and forms a rod-shaped configuration similar to that ... | 2006 | 16987985 |
| polymorphisms of the gene coding for copper/zinc superoxide dismutase (sod1) in patients with japanese encephalitis. | japanese encephalitis is the commonest form of encephalitis globally. most cases develop characteristic encephalitis but some also present with flaccid paralysis. the paralysis is secondary to damage at the alpha motor neurone, the site that is also damaged in amyotrophic lateral sclerosis (als). the gene coding for superoxide dismutase 1 (sod1) is thought to be involved in als and may also be linked to susceptibility to japanese encephalitis. to investigate this possibility, polymorphisms in th ... | 2006 | 16989689 |
| molecular biology of flaviviruses. | flaviviruses are enveloped viruses with a single-stranded, 10.7kb positive-sense rna genome. the genomic rna, which has a 5' cap but no poly(a) tail, is translated as a single polyprotein that is then cleaved into three structural proteins and seven non-structural (ns) proteins by both viral and host proteases. the ns proteins include an rna-dependent rna polymerase (ns5), a helicase/protease (ns3), and other proteins that form part of the viral replication complex. sequences and structures in t ... | 2006 | 17319152 |
| development of novel antivirals against flaviviruses. | dengue virus is responsible for a significant amount of human disease in predominantly tropical areas of the world. much effort has focused on the development of vaccines against the four serotypes of dengue, and within the next few years a vaccine is anticipated. less progress has been made at developing antivirals that might reduce disease severity. recent advances in the structural biology of dengue virus and other flaviviruses have opened new possibilities for the rational design of small mo ... | 2006 | 17319153 |
| entry functions and antigenic structure of flavivirus envelope proteins. | the envelope proteins (e) of flaviviruses form an icosahedral cage-like structure of homodimers that cover completely the surface of mature virions and are responsible for receptor-binding and membrane fusion. fusion is triggered by the acidic ph in endosomes which induces dramatic conformational changes of e that drive the merger of the membranes. we have identified an alternative trigger that induces the first phase of the fusion process only, but then leads to an arrest at an intermediate sta ... | 2006 | 17319154 |
| multiple enzyme activities of flavivirus proteins. | dengue viruses (denv) have 5'-capped rna genomes of (+) polarity and encode a single polyprotein precursor that is processed into mature viral proteins. ns2b, ns3 and ns5 proteins catalyse/activate enzyme activities that are required for key processes in the virus life cycle. the heterodimeric ns2b/ns3 is a serine protease required for processing. using a high-throughput protease assay, we screened a small molecule chemical library and identified -200 compounds having > or = 50% inhibition. more ... | 2006 | 17319155 |
| towards the design of flavivirus helicase/ntpase inhibitors: crystallographic and mutagenesis studies of the dengue virus ns3 helicase catalytic domain. | infectious diseases caused by flaviviruses are important emerging public health concerns and new vaccines and therapeutics are urgently needed. the ns3 protein from flavivirus is a multifunctional protein with protease, helicase and nucleoside 5' triphosphatase activities (ntpase). thus, ns3 plays a crucial role in viral replication and represents an interesting target for the development of specific antiviral inhibitors. we have solved the structure of an enzymatically active fragment of the de ... | 2006 | 17319156 |
| finding new medicines for flaviviral targets. | with the incidence of dengue fever increasing all over the world, there is an urgent need for therapies. while drug discovery for any disease is a long and difficult process with uncertain success, dengue fever poses an additional complication in that most of the target patient population is young and lives in developing countries with very limited health care budgets. recent progress in drug discovery for dengue and an analysis of approaches toward hepatitis c virus (hcv) therapeutics suggest t ... | 2006 | 17319157 |
| organization of flaviviral replicase proteins in virus-induced membranes: a role for ns1' in japanese encephalitis virus rna synthesis. | the organization of flaviviral replicase proteins within the membrane-bound replication complexes of west nile (wnv), dengue (denv) and japanese encephalitis viruses (jev) was probed by investigating the combined effect of detergents and trypsin on both viral replicase activity and profile of metabolically labelled viral proteins. while trypsin treatment of virus-induced membrane fractions degraded the vast majority of replicase proteins, viral rna-dependent rna polymerase (rdrp) activity remain ... | 2006 | 17319159 |
| crm1-dependent nuclear export of dengue virus type 2 ns5. | the dengue virus multidomain rna polymerase ns5 has been observed in the nucleus in mammalian infected cell systems. we previously showed that ns5 nuclear localization is mediated by two nuclear targeting signals within the ns5 interdomain region that are recognized by distinct members of the importin superfamily of intracellular transporters. intriguingly, we have recently found that ns5 also possesses the ability to be exported from the nucleus by the importin family member crm1 (exportin 1) b ... | 2006 | 17319160 |
| developing vaccines against flavivirus diseases: past success, present hopes and future challenges. | vaccination still remains the most cost-effective way of protecting large populations against infectious disease. safe and effective vaccines are available against most pathogenic flaviviruses and in recent years substantial progress has been made in developing vaccines against dengue. dengue vaccines based on conventional and recombinant dna technologies are being assessed and initial results are encouraging. many other experimental vaccines have been developed, but despite the intensity of eff ... | 2006 | 17319163 |
| mouse and hamster models for the study of therapy against flavivirus infections. | small animal models that are reminiscent of flaviviral disease in human will be instrumental in identifying therapeutic strategies against flavivirus infections. here we review models in mice and hamsters for the most clinically important flaviviruses: dengue virus, yellow fever virus, west nile virus, japanese encephalitis virus and tick-borne encephalitis virus. in addition, models are discussed that employ no known vector viruses such as the modoc virus. these viruses can be manipulated in bs ... | 2006 | 17319165 |
| secretion of flaviviral non-structural protein ns1: from diagnosis to pathogenesis. | flaviviruses are major arthropod-borne human pathogens responsible for life-threatening encephalitis, hepatitis and haemorrhagic fevers. these enveloped, single-stranded, positive-sense rna viruses encode a polyprotein precursor of about 3400 amino acids, processed into three structural and seven non-structural proteins. the non-structural glycoprotein ns1 is essential for flavivirus viability. during host-cell infection in vitro, ns1 is found associated with intracellular organelles as a requis ... | 2006 | 17319166 |
| surveillance of viral haemorrhagic fevers in ghana: entomological assessment of the risk of transmission in the northern regions. | summary | 2006 | 17496987 |
| west nile virus activity in latin america and the caribbean. | west nile virus (flavivirus: flaviviridae; wnv) has spread rapidly throughout the caribbean basin since its initial detection there in 2001. this report summarizes our current knowledge of wnv transmission in tropical america. | 2006 | 16551385 |
| differential dengue cross-reactive and neutralizing antibody responses in balb/c and swiss albino mice induced by immunization with flaviviral vaccines and by infection with homotypic dengue-2 virus strains. | we investigated whether cross-reactive and/or cross-protective antibodies against dengue virus could be generated in 6-week-old balb/c mice by immunization with currently approved flaviviral vaccines, i.e., japanese encephalitis (je) biken and yellow fever (yf) 17d. cross-reactivity with dengue antigens was apparent in at least one-third each of je-vaccinated mouse sera and of je/yf-vaccinated mouse sera by dengue enzyme immunoassay, but was not detected in sera of mice immunized with yf vaccine ... | 2006 | 16553548 |
| unexpected similarity between the cytosolic west nile virus ns3 and the secretory furin-like serine proteinases. | many viral proteins undergo proteolytic processing events that are required for virus infection and virion assembly. in this issue of biochemical journal, strongin and co-workers report that the ns3 protease from west nile virus unexpectedly cleaves certain substrates at pairs of basic residues, a specificity that resembles that of the furin-like pcs (proprotein convertases). this led to the demonstration that furin/pc inhibitors containing poly(d-arginine) are also potent inhibitors of ns3, and ... | 2006 | 16371006 |
| probing the substrate specificity of the dengue virus type 2 ns3 serine protease by using internally quenched fluorescent peptides. | the ns3 (dengue virus non-structural protein 3) serine protease of dengue virus is an essential component for virus maturation, thus representing an attractive target for the development of antiviral drugs directed at the inhibition of polyprotein processing. in the present study, we have investigated determinants of substrate specificity of the dengue virus ns3 protease by using internally quenched fluorogenic peptides containing abz (o-aminobenzoic acid; synonymous to anthranilic acid) and 3-n ... | 2006 | 16489931 |
| analysis of the endocytic pathway mediating the infectious entry of mosquito-borne flavivirus west nile into aedes albopictus mosquito (c6/36) cells. | the initial interaction between mosquito-borne flavivirus west nile and mosquito cells is poorly characterized. this study analyzed the endocytic and the associated signaling pathway that mediate the infectious entry of west nile virus (wnv) into mosquito cell line (c6/36). pretreatment of c6/36 cells with pharmacological drugs that blocks clathrin-mediated endocytosis significantly inhibited virus entry. furthermore, the transfection of functional blocking antibody against clathrin molecules an ... | 2006 | 16490225 |
| prevalence and clinical significance of hgv/gbv-c infection in patients with chronic hepatitis b or c. | hepatitis g virus/gb virus-c (hgv/gbv-c) is a newly identified flavivirus. its clinical significance in chronic hepatitis b and c remains controversial. infection with hgv/gbv-c was surveyed in 500 blood donors, 130 patients with chronic hepatitis b and 173 with hepatitis c, with chronic liver disease, cirrhosis, and/or hepatocellular carcinoma (hcc). hgv/gbv-c rna was detected by reverse transcription-polymerase chain reaction. an antibody to hgv/gbv-c's second envelope protein (anti-e2 ab) was ... | 2006 | 16495630 |
| rnase l plays a role in the antiviral response to west nile virus. | alleles at the flv locus determine disease outcome after a flavivirus infection in mice. although comparable numbers of congenic resistant and susceptible mouse embryo fibroblasts (mefs) are infected by the flavivirus west nile virus (wnv), resistant mefs produce approximately 100- to 150-fold lower titers than susceptible ones and flavivirus titers in the brains of resistant and susceptible animals can differ by >10,000-fold. the flv locus was previously identified as the 2'-5' oligoadenylate s ... | 2006 | 16501108 |
| functional characterization of the ns2b/ns3 protease complex from seven viruses belonging to different groups inside the genus flavivirus. | the genus flavivirus, family flaviviridae, comprises more than 70 viruses. many of them cause severe, potentially fatal, human diseases. human vaccines are available for only three viruses and no effective antiviral drug is available. in order to limit the consequences of infections with flaviviruses, a promising approach consists in developing specific compounds that target the virus-encoded ns2b/ns3 protease complex, which is crucial for the viral polyprotein processing. in order to develop su ... | 2006 | 16504332 |
| bird-baited traps for surveillance of west nile mosquito vectors: effect of bird species, trap height, and mosquito escape rates. | host-seeking mosquitoes were sampled in bird-baited traps at four sites in new york state in 2003-2004. trap placement and efficacy of chickens, gallus gallus domesticus l., as bait compared with house sparrows, passer domesticus l., an important reservoir of west nile virus (family flaviviridae, genus flavivirus, wnv), was evaluated. each site had a chicken-baited trap near ground level (approximately 1.5 m) and in the tree canopy (approximately 9 m), and a house sparrow-baited trap at ground l ... | 2006 | 16506452 |
| quantitation of flaviviruses by fluorescent focus assay. | an indirect immunofluorescence assay for quantitation of flaviviruses was developed as an alternative to the standard plaque assay. the assay was validated with west nile virus (wnv), st. louis encephalitis virus (slev), and dengue virus (denv) types 1-4. vero cells were plated in 8-well chamber slides, and infected with 10-fold serial dilutions of virus. about 1-3 days after infection, cells were fixed, incubated with specific monoclonal antibody, and stained with a secondary antibody labeled w ... | 2006 | 16510196 |
| isolation of a new strain of the flavivirus cell fusing agent virus in a natural mosquito population from puerto rico. | the genus flavivirus contains approximately 70 single-stranded, positive-sense rna viruses that are mosquito-borne, tick-borne or have no known vector. two discoveries support previous suggestions of the existence of a large number of unsampled flaviviruses: (i) a new flavivirus, kamiti river virus, was recently isolated from kenyan mosquitoes, and (ii) sequences with high similarity to those of flaviviruses have been found integrated into the genome of aedes mosquitoes, suggesting a past infect ... | 2006 | 16528021 |
| molecular evolution of dengue 2 virus in puerto rico: positive selection in the viral envelope accompanies clade reintroduction. | dengue virus is a circumtropical, mosquito-borne flavivirus that infects 50-100 million people each year and is expanding in both range and prevalence. of the four co-circulating viral serotypes (denv-1 to denv-4) that cause mild to severe febrile disease, denv-2 has been implicated in the onset of dengue haemorrhagic fever (dhf) in the americas in the early 1980s. to identify patterns of genetic change since denv-2's reintroduction into the region, molecular evolution in denv-2 from puerto rico ... | 2006 | 16528038 |
| genome analysis and phylogenetic relationships between east, central and west african isolates of yellow fever virus. | yellow fever virus (yfv), a reemerging disease agent in africa and south america, is the prototype member of the genus flavivirus. based on examination of the prm/m, e and 3' non-coding regions of the yfv genome, previous studies have identified seven genotypes of yfv, including the angolan, east/central african and east african genotypes, which are highly divergent from the prototype strain asibi. in this study, full genome analysis was used to expand upon these genetic relationships as well as ... | 2006 | 16528039 |
| structural basis for the activation of flaviviral ns3 proteases from dengue and west nile virus. | the replication of flaviviruses requires the correct processing of their polyprotein by the viral ns3 protease (ns3pro). essential for the activation of ns3pro is a 47-residue region of ns2b. here we report the crystal structures of a dengue ns2b-ns3pro complex and a west nile virus ns2b-ns3pro complex with a substrate-based inhibitor. these structures identify key residues for ns3pro substrate recognition and clarify the mechanism of ns3pro activation. | 2006 | 16532006 |
| development of an enzyme-linked immunosorbent assay for serological diagnosis of tick-borne encephalitis using subviral particles. | the similarity of symptoms produced by tick-borne encephalitis (tbe) and japanese encephalitis (je) and the high degree of cross-reactivity between tbe and je viruses by serological tests make the development of a differential diagnostic test a priority. in this study, recombinant prm/e proteins of tbe virus strain oshima 5-10 expressed in mammalian cells resulted in the release of subviral particles (sps) into the culture medium. using the sps as antigens, enzyme-linked immunosorbent assay (eli ... | 2006 | 16540179 |
| rna secondary structure in the coding region of dengue virus type 2 directs translation start codon selection and is required for viral replication. | dengue virus is a positive-strand rna virus and a member of the genus flavivirus, which includes west nile, yellow fever, and tick-borne encephalitis viruses. flavivirus genomes are translated as a single polyprotein that is subsequently cleaved into 10 proteins, the first of which is the viral capsid (c) protein. dengue virus type 2 (denv2) and other mosquito-borne flaviviruses initiate translation of c from a start codon in a suboptimal context and have multiple in-frame augs downstream. here, ... | 2006 | 16474125 |
| a single amino acid substitution in the west nile virus nonstructural protein ns2a disables its ability to inhibit alpha/beta interferon induction and attenuates virus virulence in mice. | alpha/beta interferons (ifn-alpha/beta) are key mediators of the innate immune response against viral infection. the ability of viruses to circumvent ifn-alpha/beta responses plays a crucial role in determining the outcome of infection. in a previous study using subgenomic replicons of the kunjin subtype of west nile virus (wnv(kun)), we demonstrated that the nonstructural protein ns2a is a major inhibitor of ifn-beta promoter-driven transcription and that a single amino acid substitution in ns2 ... | 2006 | 16474146 |
| humoral immunity and correlation between elisa, hemagglutination inhibition, and neutralization tests after vaccination against tick-borne encephalitis virus in children. | vaccination against tick-borne encephalitis (tbe) virus is the measure of choice for disease control in endemic areas, as no treatment is available. in italy, the province of belluno is one of the most active tbe virus infection foci. in this study sera were examined from vaccinated children living in areas around belluno in order to monitor the immune response after anti-tbe vaccination. for the assessment of neutralizing antibodies, a plaque reduction neutralization test (prnt) was optimized a ... | 2006 | 16458368 |
| natural infection with japanese encephalitis virus among inhabitants of japan: a nationwide survey of antibodies against nonstructural 1 protein. | in japan, only a few cases of japanese encephalitis presently occur annually, raising arguments about the necessity of vaccination. here, using a novel immunoassay, we obtained natural infection rates for 2001 of 0.2-3.4% in eight selected prefectures across japan. our results provide direct evidence of the risk of reemergence. | 2006 | 16460843 |
| the anti-yellow fever virus activity of ribavirin is independent of error-prone replication. | the precise mechanism by which the broad-spectrum anti-rna virus agent ribavirin elicits its in vitro antiviral effect has remained a matter of debate. we have demonstrated that inhibition of cellular inosine monophosphate dehydrogenase (impdh) activity, and thus depletion of intracellular gtp pools, is the predominant mechanism by which ribavirin inhibits the replication of four flavi- and two paramyxoviruses (j virol 79:1943-1947, 2005). as a consequence, induction of error catastrophe, which ... | 2006 | 16421290 |
| immunoglobulin g avidity in differentiation between early and late antibody responses to west nile virus. | in 1999 west nile virus (wnv) surfaced in the united states in the city of new york and spread over successive summers to most of the continental united states, canada, and mexico. because wnv immunoglobulin m (igm) antibodies have been shown to persist for up to 1 year, residents in areas of endemicity can have persistent wnv igm antibodies that are unrelated to a current illness with which they present. we present data on the use of igg avidity testing for the resolution of conflicting data ar ... | 2006 | 16425997 |
| biological, antigenic and phylogenetic characterization of the flavivirus alfuy. | alfuy virus (alfv) is classified as a subtype of the flavivirus murray valley encephalitis virus (mvev); however, despite preliminary reports of antigenic and ecological similarities with mvev, alfv has not been associated with human disease. here, it was shown that alfv is at least 10(4)-fold less neuroinvasive than mvev after peripheral inoculation of 3-week-old swiss outbred mice, but alfv demonstrates similar neurovirulence. in addition, it was shown that alfv is partially attenuated in mice ... | 2006 | 16432019 |
| kunjin virus replicons: an rna-based, non-cytopathic viral vector system for protein production, vaccine and gene therapy applications. | the application of viral vectors for gene expression and delivery is rapidly evolving, with several entering clinical trials. however, a number of issues, including safety, gene expression levels, cell selectivity and antivector immunity, are driving the search for new vector systems. a number of replicon-based vectors derived from positive-strand rna viruses have recently been developed, and this paper reviews the current knowledge on the first flavivirus replicon system, which is based on the ... | 2006 | 16436039 |
| evolutionary influences in arboviral disease. | arthropod-borne viruses (arboviruses) generally require horizontal transmission by arthropod vectors among vertebrate hosts for their natural maintenance. this requirement for alternate replication in disparate hosts places unusual evolutionary constraints on these viruses, which have probably limited the evolution of arboviruses to only a few families of rna viruses (togaviridae, flaviviridae, bunyaviridae, rhabdoviridae, reoviridae, and orthomyxoviridae) and a single dna virus. phylogenetic st ... | 2006 | 16568903 |
| triaryl pyrazoline compound inhibits flavivirus rna replication. | triaryl pyrazoline {[5-(4-chloro-phenyl)-3-thiophen-2-yl-4,5-dihydro-pyrazol-1-yl]-phenyl-methanone} inhibits flavivirus infection in cell culture. the inhibitor was identified through high-throughput screening of a compound library using a luciferase-expressing west nile (wn) virus infection assay. the compound inhibited an epidemic strain of wn virus without detectable cytotoxicity (a 50% effective concentration of 28 microm and a compound concentration of >or=300 microm required to reduce 50% ... | 2006 | 16569847 |
| functional analysis of the tick-borne encephalitis virus cyclization elements indicates major differences between mosquito-borne and tick-borne flaviviruses. | the linear, positive-stranded rna genome of flaviviruses is thought to adopt a circularized conformation via interactions of short complementary sequence elements located within its terminal regions. this process of rna cyclization is a crucial precondition for rna replication. in the case of mosquito-borne flaviviruses, highly conserved cyclization sequences (cs) have been identified, and their functionality has been experimentally confirmed. here, we provide an experimental identification of c ... | 2006 | 16571826 |
| japanese encephalitis: development of new candidate vaccines. | japanese encephalitis (je) is the most common form of viral encephalitis that appears in the form of frequent epidemics of brain fever throughout southeast asia, china and india. the disease is caused by a flavivirus named japanese encephalitis virus that is spread to humans by mosquitoes. an internationally approved mouse brain-derived inactivated vaccine has been available that is relatively expensive, gives immunity of uncertain duration and is not completely safe. cell culture-derived inacti ... | 2006 | 16597211 |
| understanding helicases as a means of virus control. | helicases are promising antiviral drug targets because their enzymatic activities are essential for viral genome replication, transcription, and translation. numerous potent inhibitors of helicases encoded by herpes simplex virus, severe acute respiratory syndrome coronavirus, hepatitis c virus, japanese encephalitis virus, west nile virus, and human papillomavirus have been recently reported in the scientific literature. some inhibitors have also been shown to decrease viral replication in cell ... | 2006 | 16611118 |
| regulated cleavages at the west nile virus ns4a-2k-ns4b junctions play a major role in rearranging cytoplasmic membranes and golgi trafficking of the ns4a protein. | a common feature associated with the replication of most rna viruses is the formation of a unique membrane environment encapsulating the viral replication complex. for their part, flaviviruses are no exception, whereupon infection causes a dramatic rearrangement and induction of unique membrane structures within the cytoplasm of infected cells. these virus-induced membranes, termed paracrystalline arrays, convoluted membranes, and vesicle packets, all appear to have specific functions during rep ... | 2006 | 16611922 |
| [west nile virus fever]. | west nile virus (wnv) is a member of the flaviviridae family, genus flavivirus. its reservoir hosts are wild birds. infection is transmitted to humans by infected mosquitoes of the genus culex. in most cases, it is either asymptomatic or manifests itself as mild fever. typically, wnv illnesshas a sudden onset with fever above 39 degrees c and accompanying symptoms such as chills, headache, arthralgia, myalgia, back ache, cough and sore throat. gastrointestinal symptoms are frequently reported. g ... | 2006 | 16617842 |
| impact of trap elevation on estimates of abundance, parity rates, and body size of culex pipiens and culex restuans (diptera: culicidae). | trapping success, abundance, parity rate, and body size indices of culex pipiens (l.) and culex restuans theobald, important vectors of west nile virus (family flaviviridae, genus flavivirus, wnv), were determined for specimens captured from both ground level (approximately 1-m) and elevated (approximately 6- to 7-m) co2-baited cdc miniature light traps. mosquitoes were collected from six study sites in albany county, new york, from mid-may to mid-october 2004. there was no significant differenc ... | 2006 | 16619596 |
| laboratory transmission of japanese encephalitis and west nile viruses by molestus form of culex pipiens (diptera: culicidae) collected in uzbekistan in 2004. | we evaluated the molestus form of culex pipiens pipiens (l.) (hereafter referred to as "molestus") captured near tashkent, uzbekistan, for their ability to transmit japanese encephalitis (family flaviviridae, genus flavivirus, jev) and west nile (family flaviviridae, genus flavivirus, wnv) viruses under laboratory conditions. these molestus were highly competent laboratory vectors of wnv, with infection and dissemination rates of 96 and 81%, respectively. approximately 75% of female molestus tha ... | 2006 | 16619614 |
| effects of temperature on the transmission of west nile virus by culex tarsalis (diptera: culicidae). | culex tarsalis coquillett females were infected with the ny99 strain of west nile virus (family flaviviridae, genus flavivirus, wnv) and then incubated under constant temperatures of 10-30 degrees c. at selected time intervals, transmission was attempted using an in vitro capillary tube assay. the median time from imbibing an infectious bloodmeal until infected females transmitted wnv (median extrinsic incubation period, eip50) was estimated by probit analysis. by regressing the eip rate (invers ... | 2006 | 16619616 |
| overwintering of west nile virus in southern california. | west nile virus (family flaviviridae, genus flavivirus, wnv) invaded southern california during 2003, successfully overwintered, amplified to epidemic levels, and then dispersed to every county in the state. although surveillance programs successfully tracked and measured these events, mechanisms that allowed the efficient overwintering and subsequent amplification of wnv have not been elucidated. our current research provided evidence for three mechanisms whereby wnv may have persisted in south ... | 2006 | 16619621 |
| a single amino acid substitution in the central portion of the west nile virus ns4b protein confers a highly attenuated phenotype in mice. | west nile virus (wnv) ns4b is a small hydrophobic nonstructural protein that is hypothesized to participate both in viral replication and evasion of host innate immune defenses. the protein has four cysteine residues (residues 102, 120, 227, and 237). since cysteines are often critical for the function of proteins, each of the four cysteine residues found in wnv ns4b was mutated to serine by site-directed mutagenesis. while three of these substitutions had little effect on replication or mouse v ... | 2006 | 16624366 |
| limited pathogenicity of usutu virus for the domestic goose (anser anser f. domestica) following experimental inoculation. | usutu virus (usuv) is a mosquito-borne flavivirus of the japanese encephalitis virus group, which has been associated with avian mortality in austria since 2001. the affected birds are predominantly eurasian blackbirds (turdus merula). in the present study, the pathogenicity of usuv for domestic geese (anser anser f. domestica) was investigated. eleven 2-week-old geese were inoculated intramuscularly with 5 x 10(4) 50% tissue culture infectious dose of usuv strain vienna-2001 blackbird. no clini ... | 2006 | 16629984 |
| comparative mechanistic studies of de novo rna synthesis by flavivirus rna-dependent rna polymerases. | flavivirus protein ns5 harbors the rna-dependent rna polymerase (rdrp) activity. in contrast to the rdrps of hepaci- and pestiviruses, which belong to the same family of flaviviridae, ns5 carries two activities, a methyltransferase (mtase) and a rdrp. rdrp domains of dengue virus (dv) and west nile virus (wnv) ns5 were purified in high yield relative to full-length ns5 and showed full rdrp activity. steady-state enzymatic parameters were determined on homopolymeric template poly(rc). the presenc ... | 2006 | 16631221 |
| innate and adaptive cellular immunity in flavivirus-naïve human recipients of a live-attenuated dengue serotype 3 vaccine produced in vero cells (vdv3). | vdv3, a clonal derivative of the mahidol live-attenuated dengue 3 vaccine was prepared in vero cells. despite satisfactory preclinical evaluation, vdv3 was reactogenic in humans. we explored whether immunological mechanisms contributed to this outcome by monitoring innate and adaptive cellular immune responses for 28 days after vaccination. while no variations were seen in serum il12 or tnfalpha levels, a high ifngamma secretion was detected from day 8, concomitant to ifnalpha, followed by il10. ... | 2006 | 16632108 |
| molecular characterization and clinical evaluation of dengue outbreak in 2002 in bangladesh. | during the febrile illness epidemic in bangladesh in 2002, 58 people died out of the 6,132 affected. two hundred hospitalized patients were analyzed clinically, serologically and virologically to determine the features of this dengue infection. among the 10- to 70-year-old age group of the 200 clinically suspected dengue patients, 100 (50%) were confirmed as dengue cases by virus isolation and dengue igm-capture elisa. of the 100 dengue-confirmed cases, the mean age was 29.0 (+/-12.4). the possi ... | 2006 | 16632907 |
| [epitope mapping of antigenic determinants of hepatitis c virus proteins by phage display]. | study of individual hepatitis c (hcv) proteins could help to find a molecular structure and conformation, localization of antigenic and immunogenic determinants, to reveal of protective epitopes. it is necessary for practical medicine - development of diagnostic test-systems, vaccines and therapeutics. linear and conformation dependent epitopes of hcv proteins was localized in this work and immunogenic properties of phage displayed peptides screened on monoclonal antibodies to hcv proteins have ... | 2006 | 16637277 |
| [isolation and identification of japanese encephalitis virus in liaoning province]. | to study arboviruses carried by mosquitoes in liaoning province in 2002. | 2006 | 16642222 |
| comparative attractiveness of two chicken breeds to mosquitoes in southern california. | each transmission season (april-october), mosquito control districts deploy more than 2,000 white leghorn hens as sentinels in california's arbovirus surveillance program. in 2002, rhode island red hybrids were used instead, because of insufficient availability of leghorns. although arboviral seroconversions occurred in both breeds, their attractiveness to host-seeking mosquitoes was not compared. during august and september 2004, florida medical entomology laboratory traps, each containing 1 he ... | 2006 | 16646319 |
| tick-borne disease systems: mapping geographic and phylogenetic space. | evidence is presented that the evolution of the tick-borne flaviviruses is driven by biotic factors, principally the exploitation of new hosts as transmission routes. because vector-borne diseases are limited by climatic conditions, however, abiotic factors have the potential to direct and constrain the evolutionary pathways. this idea is explored by testing the hypothesis that closely related viruses occupy more similar eco-climatic spaces than do more distantly related viruses. a statistical c ... | 2006 | 16647973 |
| a single tube rt-pcr assay for the detection of mosquito-borne flaviviruses. | mosquito-borne flaviviruses include several important agents of human disease and have provided striking examples of emerging infections. in this study we present the design and validation of a single tube rt-pcr assay using a pair of consensus primers for the detection of mosquito-borne flaviviruses. sequencing of the amplicons permits the species identification. the assay was validated using rna from the yellow fever virus vaccine strain and from representative strains of dengue viruses 1, 2, ... | 2006 | 16650488 |
| fatal hemorrhagic fever caused by west nile virus in the united states. | most west nile virus (wnv) infections in humans are asymptomatic; severe disease occurs in relatively few patients and typically manifests as encephalitis, meningitis, or acute flaccid paralysis. a few cases of life-threatening disease with diffuse hemorrhagic manifestations have been reported in africa; however, this clinical presentation has not been documented for any of the >16,700 cases of wnv disease reported in the united states during 1999-2004. we describe a case of fulminant wnv infect ... | 2006 | 16652309 |
| expression of foreign protein epitopes at the surface of recombinant yellow fever 17d viruses based on three-dimensional modeling of its envelope protein. | the yellow fever (yf) 17d vaccine is a live attenuated virus, and its genetic manipulation constitutes a new platform for vaccine development. in this article, we review one of the possible approaches to enable this development, which is the insertion of foreign protein epitopes into different locations of the genome. we describe the three-dimensional (3d) modeling of the yf 17d virus e protein structure based on tick-borne encephalitis (tbe) and the identification of a potential insertion site ... | 2006 | 16679518 |
| serological evidence for japanese encephalitis and west nile viruses in domestic animals of nepal. | a regional survey was conducted in nepal for antibody to japanese encephalitis virus (jev) in domestic animals. sera from pigs, and limited numbers of ducks and horses were collected from 16 districts in 2002-2003 and subjected to three serological tests. of 270 porcine sera tested by c-elisa, 55% were found positive for the presence of antibodies against japanese encephalitis virus. additional testing for igm antibody to jev revealed less than 2% of c-elisa positive sera had evidence of recent ... | 2006 | 16697904 |
| nuclear localization of flavivirus rna synthesis in infected cells. | flaviviral replication is believed to be exclusively cytoplasmic, occurring within virus-induced membrane-bound replication complexes in the host cytoplasm. here we show that a significant proportion (20%) of the total rna-dependent rna polymerase (rdrp) activity from cells infected with west nile virus, japanese encephalitis virus (jev), and dengue virus is resident within the nucleus. consistent with this, the major replicase proteins ns3 and ns5 of jev also localized within the nucleus. ns5 w ... | 2006 | 16699025 |
| genetic characterization of st. louis encephalitis virus isolated from human in são paulo, brazil. | the molecular characterization of sph253157, a new strain of st. louis encephalitis virus (slev), isolated in 2004 from the first case of human infection recognized in the state of são paulo, brazil, is reported. the patient, presenting a febrile illness without neurological involvement, was hospitalized as a probable case of dengue fever. genomic rna was isolated from the supernatant of c6/36 cells infected with acute phase-serum specimen of the patient and the envelope gene was amplified by re ... | 2006 | 16699711 |
| production and characterization of vaccines based on flaviviruses defective in replication. | to develop new vaccine candidates for flavivirus infections, we have engineered two flaviviruses, yellow fever virus (yfv) and west nile virus (wnv), that are deficient in replication. these defective pseudoinfectious viruses (pivs) lack a functional copy of the capsid (c) gene in their genomes and are incapable of causing spreading infection upon infection of cells both in vivo and in vitro. however, they produce extracellular e protein in form of secreted subviral particles (svps) that are kno ... | 2006 | 16712897 |
| re: natural infection with japanese encephalitis virus among inhabitants of japan: a nationwide survey of antibodies against nonstructural 1 protein. | investigations to assess episodes of any natural japanese encephalitis (je) infection following prior immunizations with je inactivated vaccine in japan are commendable. employing differential production of nonstructural 1 protein ns1, during a natural infection and not by inactivated je vaccine [konishi e, shoda m, yamamoto s, arai s, tanaka-taya k, okabe n. natural infection with japanese encephalitis virus among inhabitants of japan: a nationwide survey of antibodies against nonstructural 1 p ... | 2006 | 16713036 |
| [tick-borne encephalitis (tbe) with special emphasis on infection in horses]. | the tick-borne encephalitis (tbe), also known as early summer meningo-encephalitis, is a geographically limited virus infection transmitted mainly by ticks. the importance of tbe is largely underestimated. the causative agent tbe-virus (tbev) is grouped into the genus flavivirus of the virus family flaviviridae. clinical disease including fatal outcomes has been described for men and dogs. with regard to horses only a limited number of case reports is available. in a study performed at the insti ... | 2006 | 16716050 |
| the 3' untranslated region of tick-borne flaviviruses originated by the duplication of long repeat sequences within the open reading frame. | comparative alignment of the 3'untranslated regions (3'utrs) of tick-borne flaviviruses has previously revealed short direct repeat sequences about 25-70 nucleotides long [gritsun, t.s., venugopal, k., zanotto, p.m., mikhailov, m.v., sall, a.a., holmes, e.c., polkinghorne, i., frolova, t.v., pogodina, v.v., lashkevich, v.a., gould, e.a., 1997. complete sequence of two tick-borne flaviviruses isolated from siberia and the uk: analysis and significance of the 5' and 3'-utrs. virus res. 49 (1) 27-3 ... | 2006 | 16730048 |
| blocking of interferon-induced jak-stat signaling by japanese encephalitis virus ns5 through a protein tyrosine phosphatase-mediated mechanism. | japanese encephalitis virus (jev), a mosquito-borne flavivirus that causes severe human disease, has been shown to block the interferon (ifn)-induced janus kinase signal transducer and activation of transcription (jak-stat) signaling cascade by preventing tyk2 tyrosine phosphorylation and stat activation. in this study, we demonstrate that expression of the jev nonstructural protein ns5 readily blocked ifn-stimulated jak-stat signaling events such as stat1 nuclear translocation and tyrosine phos ... | 2006 | 16731929 |
| nmr solution structure and backbone dynamics of domain iii of the e protein of tick-borne langat flavivirus suggests a potential site for molecular recognition. | flaviviruses cause many human diseases, including dengue fever, yellow fever, west nile viral encephalitis, and hemorrhagic fevers, and are transmitted to their vertebrate hosts by infected mosquitoes and ticks. domain iii of the envelope protein (e-d3) is considered to be the primary viral determinant involved in the virus-host-cell receptor interaction, and thus represents an excellent target for antiviral drug development. langat (lgt) virus is a naturally attenuated bsl-2 tbe virus and is a ... | 2006 | 16731969 |
| evaluation of potential west nile virus vectors in volgograd region, russia, 2003 (diptera: culicidae): species composition, bloodmeal host utilization, and virus infection rates of mosquitoes. | potential west nile virus (family flaviviridae, genus flavivirus, wnv) vectors were assessed during 2003 at indoor and outdoor collection sites in urban volgograd, russia, and in three nearby towns and surrounding rural areas. in total, 9,182 female mosquitoes comprising 13 species in six genera were collected. relative abundance and bloodmeal host utilization differed temporarily and spatially. during june and july in volgograd, aedes vexans (meigen) (85.4%) and culex p. pipiens l. (7.6%) were ... | 2006 | 16739415 |
| survey of aedes triseriatus (diptera: culicidae) for lacrosse encephalitis virus and west nile virus in lorain county, ohio. | from june through september 2003, we conducted a survey of female aedes triseriatus (say) for infection with la crosse encephalitis virus (family bunyaviridae, genus orthobunyavirus, lacv) and west nile virus (family flaviviridae, genus flavivirus, wnv) at three locations in lorain county, ohio. to determine infection rate and seasonal variation of both viruses in the ae. triseriatus population, ae. triseriatus were collected weekly by using gravid traps and co2-baited cdc light traps and tested ... | 2006 | 16739420 |
| emergence of west nile virus in mosquito (diptera: culicidae) communities of the new mexico rio grande valley. | the first appearances of west nile virus (family flaviviridae, genus flavivirus, wnv) in new mexico were reported in late summer to early fall 2002. several dead birds tested positive for wnv, and 78 equine cases were confirmed. all mosquito pools tested (n = 268) were negative. a statewide surveillance program was launched in may 2003 to study the emergence and spread of this new arbovirus in mosquitoes from the rio grande valley. mosquitoes were trapped at 32 sites along a 750-km stretch of th ... | 2006 | 16739421 |
| the acre project: the epidemiology of malaria and arthropod-borne virus infections in a rural amazonian population. | the authors describe the baseline malaria prevalence and arbovirus seroprevalence among 467 subjects in an ongoing cohort study in rural amazonia. most subjects (72.2%) reported one or more previous episodes of malaria, and 15.6% had been hospitalized for malaria, but only 3.6% of individuals five years or older had malaria parasites detected by microscopy (10 with plasmodium vivax and 4 with p. falciparum). antibodies to alphavirus, orthobunyavirus, and/or flavivirus were detected by hemaggluti ... | 2006 | 16751971 |
| [infections caused by west nile virus]. | west nile virus (wnv) is a flavivirus related to tick-borne encephalitis virus endemic in northeast of poland. wnv circulates among wild birds, transmitted by wide range of haematophagous arthropods. several mosquito species, especially culex spp., can transmit wnv to humans. wnv is responsible for a broad range of clinical symptoms, from asymptomatic infection to severe encephalitis and polio-like myelitis. elderly persons are at especially high risk of death and severe neurological complicatio ... | 2006 | 16758745 |
| novel approach to analyzing rna aptamer-protein interactions: toward further applications of aptamers. | surface plasmon-resonance analysis using a biacore biosensor is a powerful tool for the detailed study of biomolecular interactions. the authors examined the methods of immobilizing proteins on the surface of nta, sa, and cm5 sensor chips to study rna aptamer-protein interactions. rna aptamers and their deletion variants were loaded onto a protein-immobilized sensor chip, and their binding affinities were analyzed. immobilizing the protein on a cm5 sensor chip via an anti-his-tag antibody was th ... | 2006 | 16760364 |
| impact of education on knowledge, agricultural practices, and community actions for mosquito control and mosquito-borne disease prevention in rice ecosystems in sri lanka. | mosquito-borne diseases are a major public health threat in sri lanka. a 20-week pilot education program to improve community knowledge and mosquito control with participatory and non-chemical approaches was developed, implemented, and evaluated using pre-educational and post-educational surveys in two intervention and two comparison villages. correlates of baseline knowledge were sex, number of family members, ratio of family members with malaria history, school education level, and availabilit ... | 2006 | 16760516 |
| seroprevalence and distribution of flaviviridae, togaviridae, and bunyaviridae arboviral infections in rural cameroonian adults. | arboviruses from the families flaviviridae, togaviridae, and bunyaviridae are suspected to cause widespread morbidity in sub-saharan african populations, but little research been done to document the burden and distribution of these pathogens. we tested serum samples from 256 cameroonian adults from nine rural villages for the presence of dengue-2 (den-2), west nile (wn), yellow fever (yf), chikungunya (chik), o'nyong-nyong (onn), sindbis (sin), and tahyna (tah) infection using standard plaque-r ... | 2006 | 16760524 |
| cleavage targets and the d-arginine-based inhibitors of the west nile virus ns3 processing proteinase. | mosquito-borne wnv (west nile virus) is an emerging global threat. the ns3 proteinase, which is essential for the proteolytic processing of the viral polyprotein precursor, is a promising drug target. we have isolated and biochemically characterized the recombinant, highly active ns3 proteinase. we have determined that the ns3 proteinase functions in a manner that is distantly similar to furin in cleaving the peptide and protein substrates. we determined that aprotinin and d-arginine-based 9-12- ... | 2006 | 16229682 |
| alkhurma hemorrhagic fever virus is an emerging tick-borne flavivirus. | 2006 | 16216331 | |
| a multigene analysis of the phylogenetic relationships among the flaviviruses (family: flaviviridae) and the evolution of vector transmission. | the genus flavivirus (family flaviviridae) presently comprises around 70 single-strand positive-sense rna viruses. these replicate in a range of vertebrate and invertebrate cells and may be mosquito-borne, tick-borne or have no-known-vector. since transmission mode correlates strongly with phylogeny, the flaviviruses constitute a valuable model for the evolution of vector-borne disease. attempts to resolve the higher-level taxonomic relationships of the flaviviruses through molecular phylogeneti ... | 2006 | 16172840 |
| immunogenicity of combination dna vaccines for rift valley fever virus, tick-borne encephalitis virus, hantaan virus, and crimean congo hemorrhagic fever virus. | dna vaccines for rift valley fever virus (rvfv), crimean congo hemorrhagic fever virus (cchfv), tick-borne encephalitis virus (tbev), and hantaan virus (htnv), were tested in mice alone or in various combinations. the bunyavirus vaccines (rvfv, cchfv, and htnv) expressed gn and gc genes, and the flavivirus vaccine (tbev) expressed the prem and e genes. all vaccines were delivered by gene gun. the tbev dna vaccine and the rvfv dna vaccine elicited similar levels of antibodies and protected mice f ... | 2006 | 16174542 |
| antigenicity of chimeric and cyclic synthetic peptides based on nonstructural proteins of gbv-c/hgv. | in this work, new putative epitopes located in nonstructural proteins of gbv-c/hgv were synthesized using solid-phase chemistry for their use in immunoassays. the antigens were obtained in linear, chimeric and cyclic forms with the main aim of improving the sensitivity of the enzyme immunoassays. our results showed, on one hand, that the combination of different antigens seems to be necessary to ensure good sensitivity and more specificity and, on the other hand, that cyclic compounds show highe ... | 2006 | 16180243 |
| flavivirus induces interferon-beta gene expression through a pathway involving rig-i-dependent irf-3 and pi3k-dependent nf-kappab activation. | in this study, we found that infection with flaviviruses, such as japanese encephalitis virus (jev) and dengue virus serotype 2 (den-2), leads to interferon-beta (ifn-beta) gene expression in a virus-replication- and de novo protein-synthesis-dependent manner. nf-kappab activation is essential for ifn-beta induction in jev- and den-2-infected cells. however, these two viruses seem to preferentially target different members of the interferon regulatory factor (irf) family. the activation of const ... | 2006 | 16182584 |
| japanese encephalitis virus ns2b-ns3 protease binding to phage-displayed human brain proteins with the domain of trypsin inhibitor and basic region leucine zipper. | flavivirus ns2b-ns3 proteases are associated with neurovirulence, becoming an important target for insight into the virus-induced pathogenesis. in this study, a phage-displayed human brain cdna library was used to detect possible interaction between brain proteins and the japanese encephalitis virus (jev) ns2b-ns3 protease. after six rounds of biopanning, eight high-affinity ns2b-ns3 protease-interacting phages were identified. identified ns2b-ns3 protease-interacting brain proteins contained se ... | 2006 | 16289409 |
| revisiting the liver in human yellow fever: virus-induced apoptosis in hepatocytes associated with tgf-beta, tnf-alpha and nk cells activity. | flavivirus infection as dengue and yellow fever persists as a terrible menace to pandemics, due to aedes prevalence in the americas. yellow fever is characterized by hepatocyte damage, with steatosis, apoptosis and necrosis, mainly in the midzonal region of the liver, but the injury mechanism has not been studied at the light of recent knowledge, such as the advances in cell death mechanisms, inflammatory response and cytokine cell expression tools. we studied 53 human liver paraffin embedded bl ... | 2006 | 16278000 |
| a case of post-japanese encephalitis with partial hypothalamic dysfunction showing repetitive hyperthermia in summertime. | japanese encephalitis (je) virus is a mosquito-borne virus belonging to the flavivirus family, including the west nile and st louis encephalitis viruses endemic to north america. je virus is prevalent in east asian countries and can cause acute lethal encephalitis. although vaccination programs have decreased the incidence of je in japan, the cases that do occur are often fatal or associated with considerable clinical sequelae. we report, for the first time to our knowledge, a patient who had re ... | 2006 | 16253337 |