Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin (dc-sign)-mediated enhancement of dengue virus infection is independent of dc-sign internalization signals. | dengue virus (dv) is a mosquito-borne flavivirus that causes hemorrhagic fever in humans. in the natural infection, dv is introduced into human skin by an infected mosquito vector where it is believed to target immature dendritic cells (dcs) and langerhans cells (lcs). we found that dv productively infects dcs but not lcs. we show here that the interactions between dv e protein, the sole mannosylated glycoprotein present on dv particles, and the c-type lectin dendritic cell-specific intercellula ... | 2005 | 15855154 |
| generic rt-nested-pcr for detection of flaviviruses using degenerated primers and internal control followed by sequencing for specific identification. | flaviviruses are a widespread and numerous group of arboviruses that can cause serious illness in humans. the continuous and slow spread of certain flaviviruses, such as dengue viruses, and the recent entry and spread of west nile virus to the american continent, point to the need to control these infections. this control requires the use of suitable techniques for diagnostic and surveillance programmes. a generic rt-nested-pcr that is, theoretically, able to detect each member of the group has ... | 2005 | 15847925 |
| stereophysicochemical variability plots highlight conserved antigenic areas in flaviviruses. | flaviviruses, which include dengue (dv) and west nile (wn), mutate in response to immune system pressure. identifying escape mutants, variant progeny that replicate in the presence of neutralizing antibodies, is a common way to identify functionally important residues of viral proteins. however, the mutations typically occur at variable positions on the viral surface that are not essential for viral replication. methods are needed to determine the true targets of the neutralizing antibodies. | 2005 | 15845145 |
| review on flavivirus vaccine development. proceedings of a meeting jointly organised by the world health organization and the thai ministry of public health, 26-27 april 2004, bangkok, thailand. | in light of the continuous spread of human pathogenic flaviviruses, in particular the mosquito-transmitted species, vaccine development remains a high priority on the public health agenda. on 26-27 april 2004, a conference was held in bangkok, thailand, to review current status of flavivirus vaccine development and related issues, focussing on dengue (den) and japanese encephalitis (je). this event, co-sponsored by the world health organization (who) and the thai ministry of public health, revie ... | 2005 | 15841565 |
| yellow fever virus ns2b-ns3 protease: characterization of charged-to-alanine mutant and revertant viruses and analysis of polyprotein-cleavage activities. | a series of 46 charged-to-alanine mutations in the yellow fever virus ns2b-ns3 protease, previously characterized in cell-free and transient cellular expression systems, was tested for their effects on virus recovery. four distinct plaque phenotypes were observed in cell culture: parental plaque-size (13 mutants), reduced plaque-size (17 mutants), small plaque-size (8 mutants) and no plaque-formation (8 mutants). no mutants displayed any temperature sensitivity based on recovery of virus after r ... | 2005 | 15831952 |
| competitive inhibition of the dengue virus ns3 serine protease by synthetic peptides representing polyprotein cleavage sites. | the ns3 serine protease of dengue virus is required for the maturation of the viral polyprotein and consequently represents a promising target for the development of antiviral inhibitors. however, the substrate specificity of this enzyme has been characterized only to a limited extent. in this study, we have investigated product inhibition of the ns3 protease by synthetic peptides derived from the p6-p1 and the p1'-p5' regions of the natural polyprotein substrate. n-terminal cleavage site peptid ... | 2005 | 15823576 |
| alkhumra haemorrhagic fever: case report and infection control details. | 2005 | 15816213 | |
| [west nile virus (wnv): generalities and implications for blood transfusion]. | west nile virus (wnv) is an arbovirus (genus flavivirus, family flaviviridae, transmitted to humans by mosquito bite. in most cases (80%), human infection remains asymptomatic. severe central nervous system complications (encephalitis and meningoencephalitis) are rare. in the old world, the virus circulation has been demonstrated in asia, australia, africa, middle east and europe. several outbreaks in humans have been described. following its introduction into north america in 1999, wn virus has ... | 2005 | 15814286 |
| role of the n-linked glycans of the prm and e envelope proteins in tick-borne encephalitis virus particle secretion. | the tick-borne encephalitis (tbe) virus has two membrane glycoproteins (prm and e), which each has one n-linked glycan. constructs that express prm and e proteins of tbe virus have been shown to produce virus-like particles (vlps), which have surface properties that are similar to those of infectious viruses. to reveal the function of glycosylation of the tbe virus prm and e proteins in the secretion of vlps, we expressed glycosylation-mutated prm and e proteins and compared the secretion levels ... | 2005 | 15811651 |
| recombination and flavivirus vaccines: a commentary. | 2005 | 15811640 | |
| characterization of west nile viral replication and maturation in peripheral neurons in culture. | the north american west nile virus (wnv), new york 1999 strain, appears to be highly neurotropic, and its neuroinvasiveness is an important aspect of human disease. the authors have developed an in vitro model to study wnv replication and protein processing in neurons. they compared wnv infection of the dorsal root ganglion (drg) neurons (sensory neurons) and pc-12 cells (sympathetic neurons) to wnv infection of the mosquito cell line, c6/36, and vero cells. wnv infection of both neuronal cell t ... | 2005 | 15804955 |
| hepatitis g virus rna positivity among the voluntary blood donors: a summary. | hepatitis virus infection is an increasing problem. millions of humans all over the world are infected. viral hepatitis is accepted as a significant public health problem with several life altering complications. recently, new viruses have been identified for their association with hepatitis. hepatitis g virus (hgv) is a single stranded rna virus which represents a newly discovered virus belonging to the flavivirus family. epidemiological data indicate that the virus is transmitted via blood/blo ... | 2005 | 15798660 |
| inhibition of flavivirus infections by antisense oligomers specifically suppressing viral translation and rna replication. | rna elements within flavivirus genomes are potential targets for antiviral therapy. a panel of phosphorodiamidate morpholino oligomers (pmos), whose sequences are complementary to rna elements located in the 5'- and 3'-termini of the west nile (wn) virus genome, were designed to anneal to important cis-acting elements and potentially to inhibit wn infection. a novel arg-rich peptide was conjugated to each pmo for efficient cellular delivery. these pmos exhibited various degrees of antiviral acti ... | 2005 | 15795246 |
| heterologous gene expression by infectious and replicon vectors derived from tick-borne encephalitis virus and direct comparison of this flavivirus system with an alphavirus replicon. | the flavivirus tick-borne encephaltis virus (tbev) was established as a vector system for heterologous gene expression. the variable region of the genomic 3' non-coding region was replaced by an expression cassette consisting of the reporter gene enhanced green fluorescent protein (egfp) under the translational control of an internal ribosomal entry site element, both in the context of an infectious virus genome and of a replicon lacking the genes of the surface proteins prm/m and e. the express ... | 2005 | 15784898 |
| quantitative trait loci that control dengue-2 virus dissemination in the mosquito aedes aegypti. | the mosquito aedes aegypti is the most important vector of yellow fever and dengue fever flaviviruses. ae. aegypti eradication campaigns have not been sustainable and there are no effective vaccines for dengue viruses. alternative control strategies may depend upon identification of mosquito genes that condition flavivirus susceptibility and may ultimately provide clues for interrupting transmission. quantitative trait loci affecting the ability of ae. aegypti to develop a dengue-2 infection in ... | 2005 | 15781707 |
| flaviviruses in motor neuron disease. | sporadic motor neuron disease (mnd) causes a progressive loss of motor neurons. west nile virus can attack motor neurons, so we examined whether flavivirus infection could be detected in mnd cases. spinal cord sections from 22 mnd cases were stained immunohistochemically with a flavivirus-specific antibody. no staining for flavivirus was seen in any case. sporadic mnd does not appear to arise from a recent infection with a flavivirus. | 2005 | 15779013 |
| class i and class ii viral fusion protein structures reveal similar principles in membrane fusion. | recent crystal structures of flavivirus and alphavirus fusion proteins (class ii) confirm two major principles of protein machineries that mediate the merger of two opposing lipid bilayers. first, the fusion protein can bridge both membranes tethered by two membrane anchors. second, refolding or domain rearrangement steps lead to the positioning of both anchors into close proximity at the same end of an elongated structure. although these two steps are in principle sufficient to pull two opposin ... | 2004 | 15764366 |
| development of immunoglobulin m capture enzyme-linked immunosorbent assay to differentiate human flavivirus infections occurring in australia. | we report the development of a flavivirus immunoglobulin m (igm) capture enzyme-linked immunosorbent assay (mac-elisa) which improves the determination of an infecting flavivirus serotype over that by current serological methods. a panel of 165 igm-positive sera from flavivirus patients with specific diagnostic results was tested by the flavivirus mac-elisa using a panel of 10 antigens. for 134 of these sera (81.2%), the highest reactivity was demonstrated against the infecting virus, which was ... | 2005 | 15753249 |
| in vitro host-cell susceptibility to usutu virus. | we investigated the susceptibility to usutu virus (flavivirus) of 13 permanent cell lines, 3 primary cell cultures, and chicken embryos. vero, pk-15, and goose embryo fibroblast cells developed cytopathic effects; however, viral multiplication was detected in all mammalian cell types by immunohistochemical tests. chicken embryo fibroblast cells and chicken embryos were resistant. | 2005 | 15752450 |
| novel flavivirus or new lineage of west nile virus, central europe. | a flavivirus (strain 97-103) was isolated from culex pipens mosquitoes in 1997 following floods in south moravia, czech republic. the strain exhibited close antigenic relationship to west nile virus (wnv) prototype strain eg-101 in a cross-neutralization test. in this study, mouse pathogenicity characteristics and the complete nucleotide and putative amino acid sequences of isolate 97-103, named rabensburg virus (rabv) after a nearby austrian city, were determined. rabv shares only 75%-77% nucle ... | 2005 | 15752439 |
| an infectious west nile virus that expresses a gfp reporter gene. | west nile virus is a mosquito-borne, neurotropic flavivirus that causes encephalitis in humans and animals. since being introduced into the western hemisphere in 1999, wnv has spread rapidly across north america, identifying this virus as an important emerging pathogen. in this study, we developed a dna-launched infectious molecular clone of wnv that encodes a gfp reporter gene. transfection of cells with the plasmid encoding this recombinant virus (pwnii-gfp) resulted in the production of infec ... | 2005 | 15749120 |
| [residual neurovirulence of the chimera of langat and denge-4 flaviviruses in intracerebral infection of monkeys]. | the residual neurovirulence of the previously obtained chimeric virus tp21/den4, containing the rna region encoding the pre m and e structural enzymes, strain tp21, virus langat, and the remaining part of the genome from the denge 4 virus, was studied in experiments with monkeys cercopithecus aethiops involving the intracerebral administration of the virus. the tick-borne encephalitis virus, strain absettarov, was used as positive control. a comparative analysis of the experimental and published ... | 2005 | 15747868 |
| isolation of bovine viral diarrhea virus 1, a pestivirus from autopsied lamb specimen from tamil nadu, india. | an epizootic of febrile illness among the madras red breed of sheep had occurred in 1994 in verrapuram, chennai, india. the epizootic was suspected as rift valley fever (rvf)-like sickness based on clinical features. however, its etiological agent could neither be isolated nor implicated conclusively. during the post-epizootic period a male lamb died of similar clinical features and the spleen was immediately collected. inoculation of spleen suspension in infant mouse brain yielded a virus that ... | 2004 | 15745045 |
| secretion of noninfectious dengue virus-like particles and identification of amino acids in the stem region involved in intracellular retention of envelope protein. | dna plasmids that express flavivirus premembrane/membrane (prm/m) and envelope (e) proteins in the form of virus-like particles (vlps) have an excellent potential as dna vaccine candidates against virus infection. the plasmid-expressed vlps are also useful as safe, noninfectious antigens in serodiagnostic assays. we have constructed plasmids containing the prm/m and e gene regions for denv-1, -3, and -4 that express and secrete vlps when electroporated into chinese hamster ovary cells. construct ... | 2005 | 15721358 |
| japanese encephalitis in a u.s. traveler returning from thailand, 2004. | japanese encephalitis (je) virus is a mosquito-borne flavivirus that is closely related to the west nile and st. louis encephalitis viruses endemic to north america. je virus is a leading cause of viral encephalitis in asia but is rarely reported among travelers to countries where je is endemic. this report describes a case of an unvaccinated washington resident who had je after traveling to northern thailand. the advisory committee on immunization practices (acip) recommends je vaccine for trav ... | 2005 | 15703694 |
| [the prevalence of hepatitis g virus in patients with hepatitis b and c virus infections]. | gb virus c/hepatitis g virus (gbv-c/hgv) is a recently identified flavivirus, which has been frequently detected in patients with chronic hepatitis b virus (hbv) and hepatitis c virus (hcv) infections. in this study, the prevalence of hgv-rna and antibodies to e2 envelope antigen (anti-e2) which is a marker of past infection, have been investigated in the samples of patients with hcv and hbv infections, and the prevalence rates were compared with the control group. the study group consisted of 5 ... | 2004 | 15700668 |
| duplex reverse transcription-pcr followed by nested pcr assays for detection and identification of brazilian alphaviruses and flaviviruses. | a new approach was developed for the rapid detection and identification of brazilian alphaviruses and flaviviruses. the methodology involves the genus-specific detection of alphavirus and flavivirus by a duplex reverse transcription-pcr (d-rt-pcr), followed by multiplex nested pcr (m-n-pcr) or nested pcr (n-pcr) assays for species-specific identification. by this protocol, 25 arboviruses were specifically detected and identified. detection levels between 10(1.3) and 10(3.5) 50% tissue culture in ... | 2005 | 15695666 |
| sampling phylogenetic tree space with the generalized gibbs sampler. | the generalized gibbs sampler (ggs) is a recently developed markov chain monte carlo (mcmc) technique that enables gibbs-like sampling of state spaces that lack a convenient representation in terms of a fixed coordinate system. this paper describes a new sampler, called the tree sampler, which uses the ggs to sample from a state space consisting of phylogenetic trees. the tree sampler is useful for a wide range of phylogenetic applications, including bayesian, maximum likelihood, and maximum par ... | 2005 | 15683921 |
| the topology of bulges in the long stem of the flavivirus 3' stem-loop is a major determinant of rna replication competence. | all flavivirus genomes contain a 3'terminal stem-loop secondary structure (3'sl) formed by the most downstream approximately 100 nucleotides (nt) of the viral rna. the 3'sl is required for virus replication and has been shown to bind both virus-coded and cellular proteins. results of the present study using an infectious dna for wn virus strain 956 initially demonstrated that the dengue virus serotype 2 (den2) 3'sl nucleotide sequence could not substitute for that of the wn 3'sl to support wn ge ... | 2005 | 15681432 |
| a novel mouse chr5 locus diht controls dopamine-induced hypothermia. | mice of the strain c3h.pri-flv(r), carrying genetically determined resistance to flaviviruses, have been shown to be more sensitive to the hypothermic effect of dopamine than congenic flavivirus-susceptible c3h/hejarc mice. in the current study, the greater sensitivity to dopamine-induced hypothermia observed in flavivirus-resistant mice was shown to be dose-dependent, with strain differences being the most prominent at a moderate dose of apomorphine (1 mg/kg). in addition, hypothermic responses ... | 2004 | 15672594 |
| trends in dengue diagnosis. | the conventional diagnosis of dengue virus infections includes the detection of the virus in serum or tissue samples, both by isolation in culture or through detection of specific viral molecules (genome rna or dengue antigens) and detection of specific anti-dengue antibodies (serology). isolation of dengue virus provides the most direct and conclusive approach to diagnosis, despite the demand for high-level equipment, technical skills and manpower. however, it is useless in early diagnosis beca ... | 2005 | 15672450 |
| flavivirus immunization with capsid-deletion mutants: basics, benefits, and barriers. | the flaviviruses comprise a number of arthropod-transmitted human disease agents that cause significant and increasing health threats in major parts of the world. the development of new vaccines is of vital importance, but the stringent need for safety, efficacy and cost-effectiveness together with the problems associated with the specific immune pathogenesis of some flavivirus infections impose significant challenges to innovative vaccine research. using tick-borne encephalitis virus (tbev) as ... | 2004 | 15671744 |
| molecular models of ns3 protease variants of the hepatitis c virus. | hepatitis c virus (hcv) currently infects approximately three percent of the world population. in view of the lack of vaccines against hcv, there is an urgent need for an efficient treatment of the disease by an effective antiviral drug. rational drug design has not been the primary way for discovering major therapeutics. nevertheless, there are reports of success in the development of inhibitor using a structure-based approach. one of the possible targets for drug development against hcv is the ... | 2005 | 15663787 |
| genetic characterization of yokose virus, a flavivirus isolated from the bat in japan. | yokose virus (strain oita-36) was isolated from the bat in japan in 1971. in the present study, we determined complete nucleotide sequences of yokose virus using rt-pcr and race techniques. yokose virus genome consists of 10,857 nucleotides in length (accession no. ab114858), containing a single open reading frame (3425 amino acids) encoding 11 viral proteins. we deduced the boundaries of each protein in the polyprotein sequence according to the protein cleavage sites of other flaviviruses. the ... | 2005 | 15661139 |
| neuroblastoma cell-adapted yellow fever virus: mutagenesis of the e protein locus involved in persistent infection and its effects on virus penetration and spread. | persistent infection of mouse neuroblastoma nb41a3 cells with yellow fever 17d virus generates viral variants which exhibit defective cell penetration, poor cell-to-cell spread, small plaque size and reduced growth efficiency, caused by substitution of glycine for aspartic acid or glutamic acid at positions 360 and 362 in the envelope protein. these positions occur within a charge cluster, asp360-asp361-glu362, located in domain iii, near its interface with domain i. to characterize further the ... | 2005 | 15659761 |
| inhibition of west nile virus entry by using a recombinant domain iii from the envelope glycoprotein. | the envelope glycoprotein located at the outermost surface of the flavivirus particle mediates entry of virus into host cells. in this study, the involvement of domain iii of west nile virus (wnv-diii) envelope protein in binding to host cell surface was investigated. wnv-diii was first expressed as a recombinant protein and purified after a solubilization and refolding procedure. the refolded wnv-diii protein displays a content of beta-sheets consistent with known homologous structures of other ... | 2005 | 15659760 |
| broadening the horizons for yellow fever: new uses for an old vaccine. | the vaccine against yellow fever is one of the safest and most effective ever developed. with an outstanding record in humans, has this live attenuated vaccine been overlooked as a promising vector for the development of vaccines against pathogens outside its own genus? recent studies, including a report by tao et al. on page 201 of this issue, have sparked renewed interest. | 2005 | 15657285 |
| differential induction of antiviral effects against west nile virus in primary mouse macrophages derived from flavivirus-susceptible and congenic resistant mice by alpha/beta interferon and poly(i-c). | a cell model of primary macrophages isolated from the peritoneal cavity of flavivirus-susceptible and congenic resistant mice has been used to study the extent and kinetics of antiviral effects against west nile virus upon priming with alpha/beta interferon (ifn-alpha/beta) or poly(i-c) (pic). the pattern of flavivirus resistance expressed after priming of cells in this model was in good agreement with the pattern of flavivirus resistance described in the brains of the corresponding mouse strain ... | 2005 | 15650200 |
| adaptation of west nile virus replicons to cells in culture and use of replicon-bearing cells to probe antiviral action. | flaviviruses are emerging threats to public health worldwide. recently, one flavivirus, west nile virus (wnv), has caused the largest epidemic of viral encephalitis in us history. like other flaviviruses, wnv is thought to cause a persistent infection in insect cells, but an acute cytopathic infection of mammalian cells. to study adaptation of wnv to persistently replicate in cell culture and generate a system capable of detecting antiviral compounds in the absence of live virus, we generated su ... | 2005 | 15629788 |
| the flavivirus-conserved penta-nucleotide in the 3' stem-loop of the west nile virus genome requires a specific sequence and structure for rna synthesis, but not for viral translation. | a reporting replicon of west nile virus (wn) was used to distinguish between the function of the 3' untranslated region (utr) in viral translation and rna replication. deletions of various regions of the 3' utr of the replicon did not significantly affect viral translation, but abolished rna replication. a systematic mutagenesis showed that the flavivirus-conserved penta-nucleotide (5'-cacag-3' located at the top of the 3' stem-loop of the genome) requires a specific sequence and structure for w ... | 2005 | 15629780 |
| construction and applications of yellow fever virus replicons. | subgenomic replicons of yellow fever virus (yfv) were constructed to allow expression of heterologous reporter genes in a replication-dependent manner. expression of the antibiotic resistance gene neomycin phosphotransferase ii (neo) from one of these yfv replicons allowed selection of a stable population of cells (bhk-rep cells) in which the yfv replicon persistently replicated. bhk-rep cells were successfully used to trans-complement replication-defective yfv replicons harboring large internal ... | 2005 | 15629769 |
| the majority of the nucleotides in the top loop of the genomic 3' terminal stem loop structure are cis-acting in a west nile virus infectious clone. | the flavivirus genome rna terminates with a conserved 3' stem loop (sl) structure that was shown to be essential for virus replication. a stretch of conserved nts is located in the top loop (tl) of this structure. mutation of the tl nts (5' acagugc 3') in a wnv infectious clone indicated that 3 of the 7 tl nts (5' acagugc 3') are critical for virus replication. mutation of 3 of the other nts reduced the efficiency of virus replication. the four 5' tl nts are conserved in both mosquito- and tick- ... | 2005 | 15629768 |
| infection of human dendritic cells by dengue virus activates and primes t cells towards th0-like phenotype producing both th1 and th2 cytokines. | dengue viruses (dv) infection is an important public health issue all over the world. although the pathogenesis remains unclear, the overwhelmingly triggered immune responses have been consistently observed. recently, we and other researchers demonstrated that the natural hosts for dv are dendritic cells (dc), the primary sentinels of immune system. in light of the significance of t cells in dengue virus pathogenesis, here, we examine the possible consequences of dc-t cell interaction that is su ... | 2004 | 15624700 |
| [tick borne flavivirus encephalitis]. | 2004 | 15624474 | |
| [the cloning and sequence analysis of cdna of the partial e genomic region of dengue type 4 virus from a chinese patient]. | the partial envelope (e) protein gene of dengue virus type 4 (dv4), derived from the serum of a patient with dengue fever in an epidemic during october 1993 in guangdong province of china, was cloned and sequenced. dv rna was converted to cdna by reverse transcription with random primers before the polymerase chain reaction using dv4 specific primers was performed. the amplified product of 421bp was subsequently filled in 3' recessed ends, isolated, purified and inserted into puc18 and puc19 pla ... | 1997 | 15619909 |
| [detection of flaviviruses by reverse-transcription polymerase chain reaction with universal primer set]. | for the purpose of early and rapid diagnosis of flavivirus infection, the universal primer set was selected on the ns1 gene. another five different internal primers were selected on the ns1 genes of den1, 2, 3, 4 and jev. with the universal primer set designed, the ns1 fragment about the size of 413 bp and with the five internal primers, the ns1 fragments about the sizes of 262 bp (den1), 189 bp (den2), 392 bp (den3), 97 bp (den4) and 323 bp (jev) were amplified respectively. the reverse transcr ... | 1997 | 15617345 |
| [west nile virus, an emerging arbovirus]. | the west nile virus (family flaviviridae, genus flavivirus), first isolated in 1937 in africa, is an arthropod-borne virus transmitted through culex mosquitoes bite. its natural cycle includes a vector (culex mosquitoes), a reservoir (birds of various species) and humans and large mammals are epidemiological dead-ends. progressive dissemination: this virus recently drew attention after several epidemics and epizooties were identified in france, russia, romania, and israel. however, the most stri ... | 2004 | 15614177 |
| viral rna replication in association with cellular membranes. | all plus-strand rna viruses replicate in association with cytoplasmic membranes of infected cells. the rna replication complex of many virus families is associated with the endoplasmic reticulum membranes, for example, picorna-, flavi-, arteri-, and bromoviruses. however, endosomes and lysosomes (togaviruses), peroxisomes and chloroplasts (tombusviruses), and mitochondria (nodaviruses) are also used as sites for rna replication. studies of individual nonstructural proteins, the virus-specific co ... | 2005 | 15609503 |
| live measles vaccine expressing the secreted form of the west nile virus envelope glycoprotein protects against west nile virus encephalitis. | the schwarz strain of measles virus (mv), a live attenuated rna virus, is one of the safest and most effective human vaccines available. immunization with mv vaccine expressing heterologous antigen is an attractive strategy to prevent emerging viral diseases. west nile virus (wnv), which recently emerged in north america, is an important mosquito-borne flavivirus that causes numerous cases of human encephalitis, thus urging the development of a vaccine. to evaluate the efficacy of recombinant mv ... | 2004 | 15609230 |
| a structural perspective of the flavivirus life cycle. | dengue, japanese encephalitis, west nile and yellow fever belong to the flavivirus genus, which is a member of the flaviviridae family. they are human pathogens that cause large epidemics and tens of thousands of deaths annually in many parts of the world. the structural organization of these viruses and their associated structural proteins has provided insight into the molecular transitions that occur during the viral life cycle, such as assembly, budding, maturation and fusion. this review foc ... | 2005 | 15608696 |
| bovine viral diarrhoea virus is internalized by clathrin-dependent receptor-mediated endocytosis. | bovine viral diarrhoea virus (bvdv) is a pestivirus within the family flaviviridae. in contrast to the members of the genus flavivirus, nothing is known about the viral entry route for pestiviruses. in this study, the process of bvdv infection following attachment to the cell surface was examined. bvdv clearly co-localizes with clathrin, with early endosome antigen-1 (eea-1), an early endosome marker, and also with lysosomal-associated membrane protein-2 (lamp-2), a lysosomal marker. bvdv intern ... | 2004 | 15606865 |
| tick-borne virus diseases of human interest in europe. | several human diseases in europe are caused by viruses transmitted by tick bite. these viruses belong to the genus flavivirus, and include tick-borne encephalitis virus, omsk haemorrhagic fever virus, louping ill virus, powassan virus, nairovirus (crimean-congo haemorrhagic fever virus) and coltivirus (eyach virus). all of these viruses cause more or less severe neurological diseases, and some are also responsible for haemorrhagic fever. the epidemiology, clinical picture and methods for diagnos ... | 2004 | 15606630 |
| identification of new flaviviruses in the kokobera virus complex. | novel flavivirus isolates from mosquitoes collected in northern australia were analysed by partial genomic sequencing, monoclonal antibody-binding assays and polyclonal cross-neutralization tests. two isolates were found to be antigenically distinct from, but related to, viruses of the kokobera virus complex, which currently contains kokobera (kokv) and stratford (strv) viruses. nucleotide sequence comparison of two separate regions of the genome revealed that an isolate from saibai island in th ... | 2005 | 15604438 |
| [immunity to flavivirus in amerindian population of the sierra de perijá, zulia state, venezuela]. | little information is available about flavivirus infection in amerindian populations in western venezuela. on this account the activity and seroprevalence of these viruses were determined and the hypothesis concerning the existence of a sylvatic cycle, conditioning the infection transmission of these viruses in indigenous populations, was studied. for this, blood samples from yukpas (n=144) and barí (n=110) communities were collected, 35 (yukpas=25 and barí=10) of which were processed for viral ... | 2004 | 15602900 |
| [comparative analysis of virulence of the siberian and far-east subtypes of the tick-born encephalitis virus]. | the siberian subtype of the tick-borne encephalitis virus (tev) is different from the far-east subtype by a moderate virulence observed in siberian hamsters and by a low infection development rate (100 strains were compared). no differences were found in neuro-invasiveness. clinical findings and experiments with monkeys denote the ability of the siberian subtype to provoke severe forms of tick-borne encephalitis (tbe). the inflammation-and-degenerative changes were localized in the brain cortex, ... | 2004 | 15597957 |
| an animal model for the tickborne flavivirus--omsk hemorrhagic fever virus. | the tickborne encephalitis (tbe) serocomplex of flaviviruses consists primarily of viruses that cause neurologic disease; these viruses include omsk hemorrhagic fever virus (ohfv), a virus that is genetically related to other tbe serocomplex viruses but that circulates in an ecologically distinct niche and causes markedly different human disease. the objective of this study was to examine a potential small-animal model for ohfv and to compare the pathology of infection with that of the neurotrop ... | 2004 | 15593010 |
| identification and characterization of nonsubstrate based inhibitors of the essential dengue and west nile virus proteases. | the 72 known members of the flavivirus genus include lethal human pathogens such as yellow fever, west nile, and dengue viruses. there is at present no known chemotherapy for any flavivirus and no effective vaccines for most. a common genomic organization and molecular mechanisms of replication in hosts are shared by flaviviruses with a viral serine protease playing a pivotal role in processing the viral polyprotein into component polypeptides, an obligatory step in viral replication. using the ... | 2005 | 15582469 |
| emerging flaviviruses: the spread and resurgence of japanese encephalitis, west nile and dengue viruses. | mosquito-borne flaviviruses provide some of the most important examples of emerging and resurging diseases of global significance. here, we describe three of them: the resurgence of dengue in tropical and subtropical areas of the world, and the spread and establishment of japanese encephalitis and west nile viruses in new habitats and environments. these three examples also illustrate the complexity of the various factors that contribute to their emergence, resurgence and spread. whereas some of ... | 2004 | 15577938 |
| identification and enzymatic characterization of ns2b-ns3 protease of alkhurma virus, a class-4 flavivirus. | alkhurma virus (alkv) is a recently discovered class-4 flavivirus that was responsible for several cases of severe haemorrhagic fever in humans in saudi arabia. it has been shown for other flaviviruses that processing of the viral polyprotein is partly due to the virus-encoded ns2b/ns3 trypsin-like serine protease. as the viral proteinase plays a critical role in the virus replication cycle, it represents one of the main targets for antiviral therapy against members of the flavivirus genus. we r ... | 2005 | 15567034 |
| identification of tick-borne encephalitis virus ribonucleic acid in tick suspensions and in clinical specimens by a reverse transcription-nested polymerase chain reaction assay. | tick-borne encephalitis virus (tbev) is a major human pathogenic flavivirus. sensitive assays for the detection of viral rna may be valuable both for the identification of virus in ticks as well as for diagnostic purposes. | 1995 | 15566853 |
| localization and characterization of flavivirus envelope glycoprotein cross-reactive epitopes. | the flavivirus e glycoprotein, the primary antigen that induces protective immunity, is essential for membrane fusion and mediates binding to cellular receptors. human flavivirus infections stimulate virus species-specific as well as flavivirus cross-reactive immune responses. flavivirus cross-reactive antibodies in human sera create a serious problem for serodiagnosis, especially for secondary flavivirus infections, due to the difficulty of differentiating primary from secondary cross-reactive ... | 2004 | 15564505 |
| identification of residues in the dengue virus type 2 ns2b cofactor that are critical for ns3 protease activation. | proteolytic processing of the dengue virus polyprotein is mediated by host cell proteases and the virus-encoded ns2b-ns3 two-component protease. the ns3 protease represents an attractive target for the development of antiviral inhibitors. the three-dimensional structure of the ns3 protease domain has been determined, but the structural determinants necessary for activation of the enzyme by the ns2b cofactor have been characterized only to a limited extent. to test a possible functional role of t ... | 2004 | 15564480 |
| a conserved histidine in the ij loop of the semliki forest virus e1 protein plays an important role in membrane fusion. | the enveloped alphavirus semliki forest virus (sfv) infects cells via a low ph-triggered membrane fusion reaction mediated by the e1 protein. e1 is a class ii fusion protein that contains the hydrophobic fusion peptide loop and converts to a stable homotrimer during the fusion reaction. intriguingly, the fusion loop is closely associated with a loop connecting the i and j beta-strands. this ij loop plays a role in the cholesterol dependence of membrane fusion and is specifically susceptible to p ... | 2004 | 15564465 |
| rapid detection of west nile virus in birds using the vectest wnv antigen assay. | to determine if the vectest west nile virus antigen assay (for testing mosquitoes) could be adapted to detect west nile virus (wnv) rapidly and accurately in birds for screening purposes. | 2004 | 15559727 |
| toll-like receptor 3 mediates west nile virus entry into the brain causing lethal encephalitis. | west nile virus (wnv), a mosquito-borne single-stranded (ss)rna flavivirus, causes human disease of variable severity. we investigated the involvement of toll-like receptor (tlr) 3, which recognizes viral double-stranded (ds)rna, on wnv infection. tlr3-deficient (tlr3(-/-)) mice were more resistant to lethal wnv infection and had impaired cytokine production and enhanced viral load in the periphery, whereas in the brain, viral load, inflammatory responses and neuropathology were reduced compared ... | 2004 | 15558055 |
| viral envelope protein glycosylation is a molecular determinant of the neuroinvasiveness of the new york strain of west nile virus. | two new york (ny) strains of the west nile (wn) virus were plaque-purified and four variants that had different amino acid sequences at the n-linked glycosylation site in the envelope (e) protein sequence were isolated. the e protein was glycosylated in only two of these strain variants. to determine the relationship between e protein glycosylation and pathogenicity of the wn virus, 6-week-old mice were infected subcutaneously with these variants. mice infected with viruses that carried the glyc ... | 2004 | 15557236 |
| histidine 39 in the dengue virus type 2 m protein has an important role in virus assembly. | the mature flavivirus particle comprises a nucleocapsid core surrounded by a lipid bilayer containing the membrane (m) (derived from the precursor prm) and envelope (e) proteins. the formation of intracellular prm/e heterodimers occurs rapidly after translation and is believed to be important for the assembly and secretion of immature virus particles. in this study, the role of the his residue at position 39 in the m protein (m39) of dengue virus type 2 (denv-2) in the virus life cycle was inves ... | 2004 | 15557235 |
| epitope determinants of a chimpanzee fab antibody that efficiently cross-neutralizes dengue type 1 and type 2 viruses map to inside and in close proximity to fusion loop of the dengue type 2 virus envelope glycoprotein. | the epitope determinants of chimpanzee fab antibody 1a5, which have been shown to be broadly reactive to flaviviruses and efficient for cross-neutralization of dengue virus type 1 and type 2 (denv-1 and denv-2), were studied by analysis of denv-2 antigenic variants. sequence analysis showed that one antigenic variant contained a gly-to-val substitution at position 106 within the flavivirus-conserved fusion peptide loop of the envelope protein (e), and another variant contained a his-to-gln subst ... | 2004 | 15542644 |
| chimpanzee fab fragments and a derived humanized immunoglobulin g1 antibody that efficiently cross-neutralize dengue type 1 and type 2 viruses. | passive immunization with monoclonal antibodies from humans or nonhuman primates represents an attractive alternative to vaccines for prevention of illness caused by dengue viruses (denv) and other flaviviruses, including the west nile virus. in a previous study, repertoire cloning to recover fab fragments from bone marrow mrna of chimpanzees infected with all four denv serotypes (dengue virus serotype 1 [denv-1] to denv-4) was described. in that study, a humanized immunoglobulin g1 (igg1) antib ... | 2004 | 15542643 |
| evaluation of a diagnostic algorithm using immunoglobulin m enzyme-linked immunosorbent assay to differentiate human west nile virus and st. louis encephalitis virus infections during the 2002 west nile virus epidemic in the united states. | a diagnostic algorithm was developed to differentiate between human infections of west nile virus (wnv) and st. louis encephalitis virus (slev) using positive-to-negative (p/n) ratios derived from the immunoglobulin m capture enzyme-linked immunosorbent assay (mac-elisa). to validate this algorithm, we tested 1,418 serum and cerebrospinal fluid (csf) samples from confirmed wnv and slev infections collected during the wnv epidemic of 2002 in the united states. wnv p/n-to-slev p/n ratios (w/s rati ... | 2004 | 15539517 |
| experimental transmission of karshi and langat (tick-borne encephalitis virus complex) viruses by ornithodoros ticks (acari: argasidae). | selected species of mosquitoes and ornithodoros ticks were evaluated for their potential to transmit karshi and langat (tick-borne encephalitis virus complex) viruses in the laboratory. although there was no evidence of replication of karshi virus in either of the two mosquito species tested [ochlerotatus taeniorhynchus (wiedemann) or culex pipiens (l.)], karshi virus replicated in and was transmitted by all three species of ornithodoros ticks tested (ornithodoros parkeri cooley, ornithodoros so ... | 2004 | 15535630 |
| structure and dynamics of a predicted ferredoxin-like selenoprotein in japanese encephalitis virus. | homologues of the selenoprotein glutathione peroxidase (gpx) have been previously identified in poxviruses and in rna viruses including hiv-1 and hepatitis c virus (hcv). sequence analysis of the ns4 region of japanese encephalitis virus (jev) suggests it may encode a structurally related but functionally distinct selenoprotein gene, more closely related to the iron-binding protein ferredoxin than to gpx, with three highly conserved uga codons that align with essential cys residues of ferredoxin ... | 2004 | 15530818 |
| development and evaluation of an enzyme-linked immunosorbent assay for quantifying antibodies to japanese encephalitis virus nonstructural 1 protein to detect subclinical infections in vaccinated horses. | antibodies to japanese encephalitis virus (jev) nonstructural 1 (ns1) protein constitute a marker of natural jev infection among populations vaccinated with inactivated je vaccine. in japan, with few recent human je cases, the natural infection rate is critical to evaluate the necessity of continuing je vaccination. a sensitive immunochemical staining method for detecting ns1 antibodies in individuals naturally and subclinically infected with jev was previously established. here, an enzyme-linke ... | 2004 | 15528700 |
| the role of tumor necrosis factor in modulating responses of murine embryo fibroblasts by flavivirus, west nile. | murine embryo fibroblasts (mef) transcribe tumor necrosis factor (tnf) mrna and secrete soluble tnf in response to infection by west nile virus (wnv) and tnf was demonstrated to be protective against wnv infection in vitro. tnf is not required for the wnv-induced upregulation of mhc-i expression on mef, as tnf deficiency did not affect the upregulation of major histocompatibility complex class i (mhc-i) by wnv. furthermore, nf-kappab was activated by wnv in tnf-deficient mef, demonstrating that ... | 2004 | 15518815 |
| the transmembrane domains of the prm and e proteins of yellow fever virus are endoplasmic reticulum localization signals. | the immature flavivirus particle contains two envelope proteins, prm and e, that are associated as a heterodimer. virion morphogenesis of the flaviviruses occurs in association with endoplasmic reticulum (er) membranes, suggesting that there should be accumulation of the virion components in this compartment. this also implies that er localization signals must be present in the flavivirus envelope proteins. in this work, we looked for potential subcellular localization signals in the yellow feve ... | 2004 | 15507646 |
| chimerivax-west nile virus live-attenuated vaccine: preclinical evaluation of safety, immunogenicity, and efficacy. | the availability of chimerivax vaccine technology for delivery of flavivirus protective antigens at the time west nile (wn) virus was first detected in north america in 1999 contributed to the rapid development of the vaccine candidate against wn virus described here. chimerivax-japanese encephalitis (je), the first live- attenuated vaccine developed with this technology has successfully undergone phase i and ii clinical trials. the chimerivax technology utilizes yellow fever virus (yf) 17d vacc ... | 2004 | 15507637 |
| analysis of adaptive mutations in kunjin virus replicon rna reveals a novel role for the flavivirus nonstructural protein ns2a in inhibition of beta interferon promoter-driven transcription. | the establishment of persistent noncytopathic replication by replicon rnas of a number of positive-strand rna viruses usually leads to generation of adaptive mutations in nonstructural genes. some of these adaptive mutations (e.g., in hepatitis c virus) increase the ability of rna replication to resist the antiviral action of alpha/beta interferon (ifn-alpha/beta); others (e.g., in sindbis virus) may also lead to more efficient ifn production. using puromycin-selectable kunjin virus (kun) replic ... | 2004 | 15507609 |
| flavivirus encephalitis. | 2004 | 15496637 | |
| site-directed mutagenesis and kinetic studies of the west nile virus ns3 protease identify key enzyme-substrate interactions. | the flavivirus west nile virus (wnv) has spread rapidly throughout the world in recent years causing fever, meningitis, encephalitis, and fatalities. because the viral protease ns2b/ns3 is essential for replication, it is attracting attention as a potential therapeutic target, although there are currently no antiviral inhibitors for any flavivirus. this paper focuses on elucidating interactions between a hexapeptide substrate (ac-kpglkr-p-nitroanilide) and residues at s1 and s2 in the active sit ... | 2005 | 15494419 |
| characterization of tick-borne encephalitis virus from estonia. | tick-borne encephalitis virus (tbev) is a severe problem in estonia. in the present article the first genetic analysis of estonian tbev strains is described. in total, seven tbev strains were isolated from ticks (ixodes ricinus and i. persulcaus), rodents (apodemus agrarius and cletrionomys glareolus), and serum from a tick-borne encephalitis (tbe) patient. the nucleic acid sequences of the viral genome encoding almost the complete e protein (nt 41-1250) and the 3'-ncr-termini of the estonian tb ... | 2004 | 15484275 |
| proinflammatory cytokines and chemokines in humans with japanese encephalitis. | japanese encephalitis virus (jev), the mosquito-borne flavivirus, annually causes an estimated 35,000-50,000 encephalitis cases and 10,000-15,000 deaths in asia, and there is no antiviral treatment. the role played by the immune response in determining the outcome of human infection with jev is poorly understood, although, in animal models of flavivirus encephalitis, unregulated proinflammatory cytokine responses can be detrimental. | 2004 | 15478067 |
| enhancement of dengue virus translation: role of the 3' untranslated region and the terminal 3' stem-loop domain. | an essential step for a productive infection by the dengue flavivirus (den) is translation of the m(7)g-capped, nonpolyadenylated positive-sense rna genome. we have recently identified sequences within the den 3' untranslated region (utr) that modulate viral translation. here, we show that the den type 2 (den2) 3'utr stimulated translation of m(7)g-capped den2 5'utr-containing reporter mrnas in baby hamster kidney (bhk) cells compared to a 3' vector sequence. analogous to the 3' poly(a) tail, th ... | 2004 | 15476880 |
| the ns3 protein of hepatitis c virus induces caspase-8-mediated apoptosis independent of its protease or helicase activities. | apoptosis has been implicated in the pathogenesis of hepatitis c virus (hcv)-related disease. here, we show that expression of hcv ns3, or the ns2/ns3 precursor protein, in mammalian cells results in induction of apoptosis and activation of caspases. hcv ns3-induced apoptosis was blocked by a caspase-8, but not a caspase-9-specific inhibitor. hcv ns3 coimmunoprecipitated with caspase-8, but not with other caspases or with fadd. coexpression of hcv ns3 and caspase-8 resulted in aggregation of the ... | 2004 | 15476874 |
| interaction of west nile virus with alpha v beta 3 integrin mediates virus entry into cells. | the functional receptor for the flavivirus west nile (wnv) infection has been characterized in this study with a combination of biochemical and molecular approaches. a 105-kda protease-sensitive glycoprotein that binds wnv was isolated from the plasma membrane of cells permissive to wnv infection. the protein was subjected to peptide sequencing, and this glycoprotein was identified as a member of the integrin superfamily. infection of wnv was shown to be markedly inhibited in vero cells pretreat ... | 2004 | 15475343 |
| noninfectious recombinant antigen for detection of st. louis encephalitis virus-specific antibodies in serum by enzyme-linked immunosorbent assay. | proper surveillance of virus activity and a timely response to viral outbreaks depend upon the rapid diagnosis of viral infections. the immunoglobulin m (igm) antibody-capture enzyme-linked immunosorbent assay (mac-elisa) is a fast, sensitive test routinely used for the diagnosis of the medically important west nile and st. louis encephalitis flaviviruses. however, the suckling mouse brain-derived (smb) antigen used in this assay is tedious to prepare and has a risk of exposing personnel to live ... | 2004 | 15472331 |
| performance of immunoglobulin g (igg) and igm enzyme-linked immunosorbent assays using a west nile virus recombinant antigen (prem/e) for detection of west nile virus- and other flavivirus-specific antibodies. | focus technologies developed an indirect immunoglobulin g (igg) enzyme-linked immunosorbent assay (elisa) and a mu-capture igm elisa for the detection of west nile virus (wnv)-specific antibodies based on a wnv prem/e protein recombinant antigen. normal and disease state serum panels were used to assess the performance characteristics of the two wnv elisa kits. totals of 807 and 1,423 sera were used to assess the igg elisa and igm elisa kits, respectively. the focus technologies igg elisa had a ... | 2004 | 15472323 |
| complete genome analysis and molecular characterization of usutu virus that emerged in austria in 2001: comparison with the south african strain saar-1776 and other flaviviruses. | here we describe the complete genome sequences of two strains of usutu virus (usuv), a mosquito-borne member of the genus flavivirus in the japanese encephalitis virus (jev) serogroup. usuv was detected in austria in 2001 causing a high mortality rate in blackbirds; the reference strain (saar-1776) was isolated in 1958 from mosquitoes in south africa and has never been associated with avian mortality. the austrian and south african isolates exhibited 97% nucleotide and 99% amino acid identity. p ... | 2004 | 15464850 |
| epidemic west nile virus encephalitis in tunisia. | west nile fever (wnf) is a mosquito-borne flavivirus infection. it is epidemic in africa and asia. in autumn 1997, a wnf epidemic occurred in the sfax area (southeastern tunisia). fifty-seven patients were hospitalized with aseptic meningitis and/or encephalitis. search for specific anti-west nile virus (wnv) antibodies in serum and cerebrospinal fluid (csf) was performed using an elisa test. reverse transcriptase-polymerase chain reaction (rt-pcr) was used to detect the wnv genome in csf and br ... | 2005 | 15459502 |
| single point mutation in tick-borne encephalitis virus prm protein induces a reduction of virus particle secretion. | flaviviruses are assembled to bud into the lumen of the endoplasmic reticulum (er) and are secreted through the vesicle transport pathway. virus envelope proteins play important roles in this process. in this study, the effect of mutations in the envelope proteins of tick-borne encephalitis (tbe) virus on secretion of virus-like particles (vlps), using a recombinant plasmid expression system was analysed. it was found that a single point mutation at position 63 in prm induces a reduction in secr ... | 2004 | 15448368 |
| dengue-specific cd8+ t cells have both protective and pathogenic roles in dengue virus infection. | to analyze roles of memory t cells in the pathogenesis of dengue (den) virus infection, a den virus-specific cd8+ cell clone (2d42 cell) was employed to investigate its in vivo function after den virus infection using an animal model. hepg2 grafted severe combined immunodeficient (hepg2-grafted scid) mice were divided into three groups--group a: hepg2-grafted scid mice were inoculated intraperitoneally (ip) with 2d42 cells and then ip-infected with den virus type 2 (den-2); group b: hepg2-grafte ... | 2004 | 15388257 |
| transmission cycles, host range, evolution and emergence of arboviral disease. | many pandemics have been attributed to the ability of some rna viruses to change their host range to include humans. here, we review the mechanisms of disease emergence that are related to the host-range specificity of selected mosquito-borne alphaviruses and flaviviruses. we discuss viruses of medical importance, including venezuelan equine and japanese encephalitis viruses, dengue viruses and west nile viruses. | 2004 | 15378043 |
| specific interaction between the classical swine fever virus ns5b protein and the viral genome. | the ns5b protein of the classical swine fever virus (csfv) is the rna-dependent rna polymerase of the virus and is able to catalyze the viral genome replication. the 3' untranslated region is most likely involved in regulation of the pestivirus genome replication. however, little is known about the interaction between the csfv ns5b protein and the viral genome. we used different rna templates derived from the plus-strand viral genome, or the minus-strand viral genome and the csfv ns5b protein ob ... | 2004 | 15373834 |
| experimental usutu virus infection of suckling mice causes neuronal and glial cell apoptosis and demyelination. | usutu virus (usuv), a mosquito-borne flavivirus of the japanese encephalitis virus group has been responsible for avian mortality in austria since 2001. in the present study, the neuropathogenicity and neuroinvasiveness of usuv for 1-week-old suckling mice was investigated. after intraperitoneal inoculation, clinical signs like depression, disorientation, paraplegia, paralysis and coma were observed between 6 and 11 days post infection. histologically, there was widespread neuronal apoptosis esp ... | 2004 | 15372281 |
| in vivo monitoring of acute flavivirus (modoc) encephalitis with regional and whole-brain quantitative diffusion magnetic resonance imaging. | in vivo imaging of structural changes in the brain of patients with encephalitis has become an important aid in diagnostic and therapeutic procedures. diffusion-weighted magnetic resonance imaging (dwi) was employed to quantitate regional and whole-brain diffusion-weighted mri changes in a hamster model for acute flavivirus encephalitis. the regional apparent diffusion coefficient (adc) was determined in hyperintense regions seen on t2-weighted images (i.e., the thalamic area and the temporal lo ... | 2004 | 15371156 |
| cytopathological changes induced by selected brazilian flaviviruses in mouse macrophages. | scanning and transmission electron microscopy were used to analyse the ultrastructure of peritoneal mouse macrophage cells infected with brazilian flavivirus (yellow fever, rocio, bussuquara and saint louis encephalitis viruses). macrophage cells collected 3 days after viral infection had a flattened shape, with an increased number of large spikes of cytoplasm prolongations, giving an appearance of hairy cells. cytopathological changes to the macrophage cells were similar regardless of the infec ... | 2004 | 15369478 |
| different chemokine expression in lethal and non-lethal murine west nile virus infection. | west nile (wn) virus is a mosquito-borne flavivirus that can cause lethal encephalitis in humans and horses. the wn virus endemic in new york city (ny) in 1999 caused large-scale mortality of wild birds that was not evident in endemic areas in other parts of the world, and the pathogenesis of the wn virus strain isolated in ny (ny strain) appears to differ from that of previously isolated strains. however, the pathogenesis of ny strain infection remains unclear. this study examined cc (rantes/cc ... | 2004 | 15368509 |
| infectious entry of west nile virus occurs through a clathrin-mediated endocytic pathway. | the pathway of west nile flavivirus early internalization events was mapped in detail in this study. overexpression of dominant-negative mutants of eps15 strongly inhibits west nile virus (wnv) internalization, and pharmacological drugs that blocks clathrin also caused a marked reduction in virus entry but not caveola-dependent endocytosis inhibitory agent, filipin. using immunocryoelectron microscopy, wnv particles were seen within clathrin-coated pits after 2 min postinfection. double-labeling ... | 2004 | 15367621 |
| n- t-boc-amino acid esters of isomannide. potential inhibitors of serine proteases. | hepatitis c, dengue and west nile virus are some of the most important flaviviruses, that share one important serine protease enzyme. serine proteases are the most studied class of proteolytic enzyme and, in these cases, a primary target for drug discovery. in this paper, we describe the synthesis and preliminary molecular modeling studies of a novel class of n- t-boc amino acid esters derived of isomannide as potential serine proteases inhibitors. | 2004 | 15365909 |
| use of recombinant e protein domain iii-based enzyme-linked immunosorbent assays for differentiation of tick-borne encephalitis serocomplex flaviviruses from mosquito-borne flaviviruses. | the serological diagnosis of infection by flaviviruses is complicated by the presence of flavivirus cross-reactive antibodies that produce false-positive results for flavivirus infections, especially in regions where more than one virus is endemic. current diagnostic reagents for tick-borne flavivirus infection have been found to cross-react with yellow fever- or dengue virus-positive sera. this study utilized recombinant flavivirus e protein domain 3 (re-d3) as a diagnostic reagent to different ... | 2004 | 15364996 |
| can we really learn from model pathogens? | cytolytic t (tc) lymphocytes are the first order response of the adaptive immune system in the recovery from primary viral infections. these effector cells execute their function either by direct cytotoxicity through the fas or perforin pathway and/or by the release of cytokines that either directly or indirectly exert antiviral activity. mice respond to infection by closely related viruses with a vigorous tc response, which is characterized by extensive crossreactivity on target cells infected ... | 2004 | 15364054 |