Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| broad cross-reactivity with marked fine specificity in the cytotoxic t cell response to flaviviruses. | cytotoxic t (tc) cells were generated in mice of five h-2 haplotypes against the flaviviruses kunjin and west nile (wnv). a panel of recombinant vaccinia viruses which between them expressed cdna of the entire kunjin virus genome were used to infect targets. anti-kunjin virus responses to determinants derived from non-structural proteins, especially ns3, ns4a and ns4b, were dominant in most mouse strains; usually only one class i major histocompatibility complex (mhc) restriction element was inv ... | 1992 | 1375278 |
| heterologous resistance to superinfection by louping ill virus persistently infected cell cultures. | louping ill virus, a tick-borne arbovirus readily established a persistent infection in porcine kidney (ps) cells after initially inducing minor cytopathic changes. nucleotide sequence analysis of the envelope glycoprotein of the viral rna recovered from the persistently infected cells showed no changes as compared with the virus used to establish persistent infections. more than 80 per cent of the cells contained virus specific antigen when analysed by indirect immunofluorescence microscopy. th ... | 1992 | 1322654 |
| expression and identification of hepatitis c virus polyprotein cleavage products. | hepatitis c virus (hcv) is the major cause of transfusion-acquired non-a, non-b hepatitis. hcv is an enveloped positive-sense rna virus which has been classified as a new genus in the flavivirus family. like the other two genera in this family, the flaviviruses and the pestiviruses, hcv polypeptides appear to be produced by translation of a long open reading frame and subsequent proteolytic processing of this polyprotein. in this study, a cdna clone encompassing the long open reading frame of th ... | 1993 | 7679746 |
| definition of an hla-dpw2-restricted epitope on ns3, recognized by a dengue virus serotype-cross-reactive human cd4+ cd8- cytotoxic t-cell clone. | we previously reported that the clone jk34 was cross-reactive for dengue virus types 1, 2, 3, and 4 and recognized ns3 (i. kurane, m. a. brinton, a. l. samson, and f. a. ennis, j. virol. 65:1823-1828, 1991). in the present experiments, we defined the epitope at the amino acid level, with 93 15-mer overlapping peptides which cover the entire ns3. a peptide 4 which contains amino acids 251 to 265 of ns3 sensitized the autologous b lymphoblastoid cell line (lcl) to the lysis by jk34. the smallest p ... | 1993 | 7690424 |
| the langat model for tick-borne encephalitis virus. specific detection by rt-pcr. | we have developed a reverse-transcriptase polymerase chain reaction assay for rapid detection of langat (lgt) virus, a flavivirus that is closely related to the highly pathogenic tick-borne encephalitis (tbe) viruses. unlike tbe viruses, lgt virus exhibits a significantly lower virulence for man. the assay serves as a safe alternative for the development and optimization of specific assays for the highly pathogenic subtypes of tbe viruses that are endemic throughout much of europe, the former so ... | 1993 | 7505284 |
| epitope analysis of tick-borne encephalitis (tbe) complex viruses using monoclonal antibodies to envelope glycoprotein of tbe virus (persulcatus subtype). | the arrangement of envelope protein epitopes of tick-borne encephalitis viruses (tbev) (persulcatus or eastern subtype, sofjin strain and ricinus or western subtype, minsk-256 strain) and kyasanur forest disease virus (kfdv) was investigated using competitive binding of monoclonal antibodies against the sofjin e protein. the e protein of tbev sofjin strain forms three antigenic domains: e1, e2 and e3, represented by 12, 9 and 2 epitopes respectively; two additional epitopes stand alone. domains ... | 1993 | 7505512 |
| [structural proteins of hepatitis c virus]. | 1993 | 7510088 | |
| analysis of computer-predicted antibody inducing epitope on japanese encephalitis virus. | theoretical methods to delineate antibody inducing epitopes have been employed to predict antigenic determinants on envelope glycoprotein (gpe) of japanese encephalitis (je), west nile (wn) and dengue (den) i-iv viruses. a predicted region on je virus gpe 74cpttgeahnekrad87 was synthesized, conjugated to klh (klh-peptide) and used in immunization of mice. a mouse monoclonal antibody (moab ivb4) reactive to the peptide was also found to react with native je virus gpe. characterization of the idio ... | 1993 | 7516621 |
| el niño-southern oscillation and vector-borne disease. | 1993 | 7901589 | |
| immunofluorescence studies on the replication of some arboviruses in nucleated and enucleated cells. | porcine stable kidney (ps) or vero cells infected with either flavi-(japanese encephalitis--je, west nile--wn, and dengue--den-2) or alphaviruses (chikungunya--chik and sindbis--sin) were stained in indirect fluorescent antibody (fa) assay with anti-je virus monoclonal (moab) hx-3 (flavivirus cross-reactive) and polyclonal (immune pf) antibodies. by 48 hr post infection (p.i.), 15 to 20% of the three flaviviruses and chik virus infected cells, which revealed positive cytoplasmic immunofluorescen ... | 1993 | 8105654 |
| brefeldin a affects west nile virus replication in vero cells but not c6/36 cells. | a fungal metabolite brefeldin a (bfa) was used to study virus-host interaction in glycoprotein processing in west nile virus-infected vero and c6/36 cells. the results indicated that as little as 1 microgram/ml of bfa resulted in complete breakdown in the golgi organelle in infected vero cells. this led to modifications of the glycoproteins which could not be efficiently used in infectious virion formation. in contrast, as much as 10 micrograms/ml of bfa in culture medium did not affect either g ... | 1993 | 7903673 |
| cytokine concentrations in cerebrospinal fluid in flavivirus infections. | 1993 | 7939960 | |
| dengue haemorrhagic fever (dhf) outbreak in calcutta--1990. | an outbreak of dengue haemorrhagic fever (dhf) occurred in calcutta between september and december, 1990. children and young adults were the major victims. haemorrhagic manifestations and shocks were the main features in most of the hospitalised cases. five mouse pathogenic agents were isolated from 105 acute cases and all were identified as den-3. hi and cf test with 55 paired sera revealed evidence of dengue infection in 33 (60 per cent) and flavivirus group reaction including dengue in 17 (30 ... | 1993 | 8014433 |
| complete genomic sequence of powassan virus: evaluation of genetic elements in tick-borne versus mosquito-borne flaviviruses. | the complete nucleotide sequence of the positive-stranded rna genome of the tick-borne flavivirus powassan (10,839 nucleotides) was elucidated and the amino acid sequence of all viral proteins was derived. based on this sequence as well as serological data, powassan virus represents the most divergent member of the tick-borne serocomplex within the genus flaviviruses, family flaviviridae. the primary nucleotide sequence and potential rna secondary structures of the powassan virus genome as well ... | 1993 | 8097605 |
| insect-transmitted vertebrate viruses: flaviviridae. | the flaviviridae include almost 70 viruses, nearly half of which have been associated with human disease. these viruses are among the most important arthropod-borne viruses worldwide and include dengue, yellow fever, and japanese encephalitis viruses. morbidity and mortality caused by these viruses vary, but collectively they account for millions of encephalitis, hemorrhagic fever, arthralgia, rash, and fever cases per year. most of the members of this family are transmitted between vertebrate h ... | 1993 | 8100566 |
| [presence of antibodies against venezuelan equine encephalitis virus subtype vi in patients with acute febrile illness]. | in argentina, there is no record of human cases produced by dengue virus (flavivirus), but paraguay and brasil (neighbouring countries) have notified human outbreaks of dengue haemorrhagic fever. in this report, we inform the serological results of a limited human outbreak of a dengue-like acute illness that occurred in general belgrano island, formosa, argentina in april 1989. this island is 35 km far from clorinda city of paraguay river, with a human population of 150 inhabitants. the weather ... | 1993 | 8153352 |
| [flavivirus meningitis after tick bite: a new case in an urban area]. | 1993 | 8115337 | |
| [health economics of early summer meningoencephalitis in austria. effects of a vaccination campaign 1981 to 1990]. | tick-borne encephalitis (tbe) was until the early 1980s among the most frequent causes of viral induced central-nervous infectious diseases in austria. since 1981 the vaccination was forced by intensive media campaigns. aim of this study was to investigate the effects of the media campaigns and to evaluate them under health economic criteria. the number of hospitalized tbe-cases declines from 1981 to 1990, the linear trend shows a reduction from 427 to 109. if the linear trend from 1971 to 1980 ... | 1993 | 8147001 |
| iguape: a newly recognized flavivirus from são paulo state, brazil. | a new virus, sp an 71686, was isolated from sentinel mice exposed in a forest area in iguape county, são paulo state, brazil, in 1979. the results suggest [hemagglutination inhibition (hi), complement fixation, neutralization, and elisa] that sp an 71686 virus is a new arbovirus and that it demonstrates some cross-reactivity with other members of the family flaviviridae, but can be differentiated from them. although there is an intensive circulation of several arboviruses in the area, the only d ... | 1993 | 8150595 |
| rapid identification of flavivirus using the polymerase chain reaction. | a rapid and accurate detection and identification system was developed for flaviviruses that makes use of reverse transcription-polymerase chain reaction (rt-pcr). a primer pair (yf-1 and yf-3), which corresponds to the highly conserved sequence at 3' noncoding region among flaviviruses, was useful for identification of mosquito-borne flaviviruses. nine sets of species specific primer pairs were also selected to identify and distinguish species, i.e., yellow fever, west nile, murray valley encep ... | 1993 | 8097200 |
| characterization of the hepatitis c virus-encoded serine proteinase: determination of proteinase-dependent polyprotein cleavage sites. | processing of the hepatitis c virus (hcv) h strain polyprotein yields at least nine distinct cleavage products: nh2-c-e1-e2-ns2-ns3-ns4a-ns4b-ns5a-ns5b-co oh. as described in this report, site-directed mutagenesis and transient expression analyses were used to study the role of a putative serine proteinase domain, located in the n-terminal one-third of the ns3 protein, in proteolytic processing of hcv polyproteins. all four cleavages which occur c terminal to the proteinase domain (3/4a, 4a/4b, ... | 1993 | 8386278 |
| use of ns3 consensus primers for the polymerase chain reaction amplification and sequencing of dengue viruses and other flaviviruses. | consensus primers for the polymerase chain reaction were designed based on conserved motifs within the serine protease and rna helicase domains encoded by the ns 3 genes of dengue and other flaviviruses. target fragments of 470 bp were amplified on cdna templates synthesized from rnas of dengue types 1, 2, 3, and 4, japanese encephalitis, kunjin, and yellow fever viruses using random or specific downstream primers. pcr of oligo(dt)-primed cdnas from japanese encephalitis and kunjin viral rnas di ... | 1993 | 8240006 |
| australian encephalitis in western australia, 1978-1991. | to review the various clinical manifestations of murray valley encephalitis (mve) or kunjin virus encephalitis in patients in western australia. | 1993 | 8386796 |
| st louis encephalitis virus establishes a productive, cytopathic and persistent infection of sf9 cells. | the sf9 cell line, commonly used for gene expression by recombinant baculovirus, has been productively infected by st louis encephalitis (sle) virus, a flavivirus. sle viral infection produced a c.p.e. in the sf9 cells characterized by giant cells and the presence of 10-fold fewer cells in the infected cultures after the first week of infection compared with uninoculated control cultures. infected sf9 cells expressed sle viral antigens, and intracellular virus particles were observed by electron ... | 1993 | 8345362 |
| classification of a new member of the tbe flavivirus subgroup by its immunological, pathogenetic and molecular characteristics: identification of subgroup-specific pentapeptides. | the antigenic, pathogenic and molecular characteristics of turkish sheep encephalitis (tse) virus, strain tte80, were compared with other members of the tick-borne encephalitis (tbe) virus complex. monoclonal antibodies with defined specificity for the flavivirus envelope glycoprotein distinguished tse virus from louping ill (li), western or far eastern tbe, langat and powassan virus in indirect immunofluorescence, haemagglutination-inhibition and neutralization tests. on the other hand, tse vir ... | 1993 | 8249442 |
| molecular approaches for the treatment of hemorrhagic fever virus infections. | viruses causing hemorrhagic fevers in man belong to the following virus groups: togavirus (chikungunya), flavivirus (dengue, yellow fever, kyasanur forest disease, omsk hemorrhagic fever), arenavirus (argentinian hemorrhagic fever, bolivian hemorrhagic fever, lassa fever), filovirus (ebola, marburg), phlebovirus (rift valley fever), nairovirus (crimian-congo hemorrhagic fever) and hantavirus (hemorrhagic fever with renal syndrome, nephropathic epidemia). hemorrhagic fever virus infections can be ... | 1993 | 8250543 |
| [virologic detection of arboviruses in greater cormorants]. | cormorants (phalacrocorax carbo, pelecaniformes) caught in southern moravia (czech republic) in 1989-1990 were examined for arbovirus infections. isolation experiments were carried out using blood samples of 56 birds. the results were negative. serological examinations of 31 birds were performed by haemagglutination-inhibition test (hit) using 5 arboviral antigens of the genera alphavirus (sindbis--sin) and flavivirus (tick-borne encephalitis--tbe, west nile--wn) and of the family bunyaviridae ( ... | 1993 | 8346623 |
| nucleotide sequence of the envelope protein gene of the tick-borne flavivirus, kumlinge a52. | the envelope protein gene of the tick-borne flavivirus, kumlinge a52, the proto-type finnish strain, has been amplified and sequenced.* the nucleotide and deduced amino acid sequence has been analyzed and compared with the closely related tick-borne encephalitis (tbe) virus, western subtype, strain neudoerfl, isolated in austria. although these two virus strains were isolated 12 years apart from different hosts and in different countries, the envelope proteins only differed by a single amino aci ... | 1993 | 8367941 |
| rapid identification of flaviviruses based on conserved ns5 gene sequences. | two conserved regions in the sequence of the ns5 gene of flaviviruses were identified. primers were designed from the consensus sequence of these regions and were used in a reverse transcription/polymerase chain reaction (rt/pcr) to amplify a region of the central european tick-borne encephalitis virus kumlinge ns5 gene. the authenticity of the amplified fragment was confirmed by nucleotide sequencing. a band of the expected size was also obtained when this rt/pcr was applied to 13 other flavivi ... | 1993 | 8263114 |
| assessment of the antigenic structure of tick-borne encephalitis virus by the use of synthetic peptides. | the feasibility of using synthetic peptides for the identification of individual monoclonal antibody (mab)-defined epitopes was assessed on the basis of a structural model of the tick-borne encephalitis (tbe) virus envelope glycoprotein e. for this purpose a series of 19 synthetic peptides was prepared, covering most of the e protein sequence. each of the peptides was tested by elisa for reactivity with 19 protein e-specific mabs raised against tbe virus strain neudoerfl. specific reactivity was ... | 1993 | 8376978 |
| the molecular biology of tick-borne encephalitis virus. review article. | tick-borne encephalitis (tbe) virus is a member of the flavivirus genus and the family flaviviridae. like other flaviviruses such as yellow fever, japanese encephalitis or the dengue viruses, it is an important human pathogen, endemic in many european countries, russia and china. the disease can be effectively prevented by vaccination with a formalin-inactivated whole virus vaccine. in recent years major advances have been made in the understanding of the molecular biology of tbe virus, includin ... | 1993 | 8267950 |
| rapid detection of viruses of the tick-borne encephalitis virus complex by rt-pcr of viral rna. | studies were performed to identify a pair of primers, specific for the tick-borne encephalitis (tbe) virus complex of the flaviviridae, with which to develop a rapid and specific identification system based on reverse transcription and the polymerase chain reaction (rt-pcr). the specificity of a putative primer pair was examined by rt-pcr of representative viruses from other antigenic complexes of the flaviviridae and by computer sequence homology checks. all viruses of the tbe complex tested, w ... | 1993 | 8270650 |
| rapid dengue diagnosis and interpretation. | 1993 | 8277797 | |
| localization and functions of japanese encephalitis virus nonstructural proteins ns3 and ns5 for viral rna synthesis in the infected cells. | recently it has been reported that japanese encephalitis virus (jev)-specific rnas can be synthesized in vitro in the subcellular fraction including outer-nuclear membrane (takegami and hotta, 1989). the results of western blot analysis and indirect immunofluorescence test using two kinds of monospecific antisera against jev nonstructural proteins ns3 and ns5 showed that ns3 and ns5 were membrane-associated proteins and formed the complex at the perinuclear site in the infected cells. both antis ... | 1993 | 8321152 |
| genetic studies of flavivirus resistance in inbred strains derived from wild mice: evidence for a new resistance allele at the flavivirus resistance locus (flv). | studies of genetic resistance to flavivirus infection in laboratory mice have led to the development of a single model in which resistance is conferred by an autosomal dominant gene designated flvr. because of evidence suggesting that wild mice carry virus resistance genes which are not present in laboratory mice, we compared flavivirus resistance in the inbred strains casa/rk, cast/ei, and mold/rk, which are derived directly from wild mice, and the congenic strains c3h/rv (flvr/flvr) and c3h/he ... | 1993 | 8380081 |
| the ns 3 nonstructural protein of flaviviruses contains an rna triphosphatase activity. | the genome of flaviviruses consists of an infectious single-stranded rna molecule which contains a type 1 cap structure at the 5'-terminus. the cap is synthesized by rna triphosphatase, guanylyltransferase and methyltransferase. since flaviviruses replicate in the cytoplasm, it can be assumed that these functions are performed by virus-coded proteins. we previously showed that subtilisin treatment of membranes isolated from cells infected with the west nile flavivirus results in release of a 50 ... | 1993 | 8212562 |
| ir1 genes, peripheral cross-tolerance and immunodominance in mhc class i-restricted t-cell responses: an old quagmire revisited. | previous studies have shown that peripheral tolerance of one mhc molecule may influence the ability of an animal to respond to a particular antigenic determinant in the context of another mhc molecule (cross-tolerance). we describe here an investigation of the extent to which the presence of mhc molecules other than the one involved in tc cell recognition affected whether or not a particular "antigen" (mhc/peptide) was recognized during the response of mice to infection with the flavivirus, west ... | 1993 | 8225372 |
| seroepidemiology of dengue and other arboviruses in a natural population of toque macaques (macaca sinica) at polonnaruwa, sri lanka. | a seroepidemiological study of arboviruses infecting 115 wild toque macaques (macaca sinica) at polonnaruwa, sri lanka showed a high prevalence of antibodies to dengue and lumbo viruses. there was low seroprevalence of chandipura (2/115) and batai (1/115) virus antibodies, but no seropositivity to chikungunya or sindbis. there was no serological evidence of infection by japanese encephalitis (je) virus in spite of large human epidemics in the study area, indicating that toque macaques are unlike ... | 1993 | 8230174 |
| [flavivirus infections in tropical areas]. | 1993 | 8236844 | |
| possible clinical infection with edge hill virus. | 1993 | 8249078 | |
| site-directed mutagenesis of the tick-borne encephalitis virus ns3 gene reveals the putative serine protease domain of the ns3 protein. | several mutations were introduced into the putative serine protease domain of the tick-borne encephalitis virus ns3 protein and into a possible internal cleavage site within the protein. the influence of these mutations on proteolytic activity of ns3 protein and ns3' protein formation was tested in vitro. it was found that ns3' formation was not dependent on the activity of the ns3 n-terminal serine protease. mutations affecting the ser-138 residue of the ns3 protein prohibited cleavage between ... | 1993 | 8344415 |
| rna-stimulated ntpase activity associated with yellow fever virus ns3 protein expressed in bacteria. | the nonstructural protein ns3 of the prototypic flavivirus, yellow fever virus, was investigated for possession of an ntpase activity. the entire ns3 protein coding sequence and an amino-terminal truncated version thereof were engineered into escherichia coli expression plasmids. bacteria harboring these plasmids produced the expected polypeptides, which upon cell disruption were found in an insoluble aggregated material considerably enriched for the ns3-related polypeptides. solubilization and ... | 1993 | 8380474 |
| nucleotide and deduced amino acid sequence of the envelope glycoprotein of omsk haemorrhagic fever virus; comparison with other flaviviruses. | the gene encoding the envelope glycoprotein of omsk haemorrhagic fever (ohf) virus was cloned and sequenced. a freeze-dried preparation of infected suckling mouse brain suspension was used as the source material for viral rna. the derived cdna was amplified using the polymerase chain reaction and the cloned dna sequenced by dideoxynucleotide sequencing. alignment of the ohf virus sequence with those of other known tick-borne flaviviruses showed that they shared n-glycosylation sites, cysteine re ... | 1993 | 8381470 |
| deletion analysis of dengue virus type 4 nonstructural protein ns2b: identification of a domain required for ns2b-ns3 protease activity. | most proteolytic cleavages in the nonstructural protein (ns) region of the flavivirus polyprotein are effected by a virus-encoded protease composed of two viral proteins, ns2b and ns3. the n-terminal 180-amino-acid-region of ns3 includes sequences with homology to the active sites of serine proteases, and there is evidence that this portion of ns3 can mediate proteolytic cleavages. in contrast, nothing is known about required sequences in ns2b. we constructed a series of deletion mutations in th ... | 1993 | 8383225 |
| viruses as teratogens. | the ability of certain viruses to affect prenatal development in domestic animals is well documented. however, differentiating a viral-induced malformation from those caused by genetic or other environmental causes is a diagnostic dilemma. understanding how viruses interact with their embryo-fetal hosts and the potential consequences on prenatal development requires refining and dispelling some old concepts and injecting new insights into this diagnostic challenge. this article discusses several ... | 1993 | 8384522 |
| nucleotide and deduced amino acid sequence of the envelope gene of the vasilchenko strain of tbe virus; comparison with other flaviviruses. | a strain of tick-borne encephalitis virus known as vasilchenko (vs) exhibits relatively low virulence characteristics in monkeys, syrian hamsters and humans. the gene encoding the envelope glycoprotein of this virus was cloned and sequenced. alignment of the sequence with those of other known tick-borne flaviviruses and identification of the recognised amino acid genetic marker ehlpta confirmed its identity as a member of the tbe complex. however, vs virus was distinguishable from eastern and we ... | 1993 | 8384766 |
| computer-assisted identification of a putative methyltransferase domain in ns5 protein of flaviviruses and lambda 2 protein of reovirus. | a sequence motif that is conserved in a number of s-adenosylmethionine (sam)-utilizing methyltransferases and is implicated in sam binding was identified in the n-terminal portion of ns5 proteins of flaviviruses and in lambda 2 protein of reovirus. an additional conserved motif was shared by these viral proteins and two distinct groups of methyltransferases including as the prototypes rhodobacter capsulatus hydroxyneurosporene methylase (crtf gene product) and yeast 3,4-dihydroxy-5-hexaprenylben ... | 1993 | 8385698 |
| virological and immunological studies of wesselsbron virus in experimentally infected red sokoto (maradi) goats. | red sokoto goats aged four to five months were experimentally infected with the nigerian strain of wesselsbron virus. viraemia commenced 24-72 hours after infection and lasted for 3-4 days. a febrile reaction which was mostly biphasic coincided with viraemia. a 50% mortality rate was observed among infected animals. the virus was re-isolated in mice from almost every tissue (liver, spleen, lungs, brain, kidney, adrenal, lymph node and heart) obtained from dead goats. complement fixing antigens w ... | 1993 | 8389498 |
| invertebrate tissue culture as a tool to study insect-transmitted viruses: a brief introduction. | 1993 | 8391527 | |
| flavivirus premembrane protein cleavage and spike heterodimer secretion require the function of the viral proteinase ns3. | flavivirus protein biosynthesis involves the proteolytic processing of a single polyprotein precursor by host- and virus-encoded proteinases. in this study, the requirement for the proteolytic function of the viral proteinase ns3 for correct processing of a polyprotein segment encompassing the murray valley encephalitis virus structural proteins is shown. the ns3-mediated cleavage in the structural polyprotein region presumably releases the capsid protein from its membrane anchor and triggers th ... | 1993 | 8392191 |
| arbovirus infections of humans in high-risk areas of south-eastern australia: a continuing study. | to determine the current immune status of high-risk populations of new south wales and victoria to the arboviral pathogens, murray valley encephalitis (mve) and kunjin (kun) viruses, which are associated with australian encephalitis (ae), and ross river (rr) and kokobera (kok) viruses which are associated with polyarthritis. further, to estimate seroconversion rates to these viruses in high-risk populations over the 10-year period 1981-1991. | 1993 | 8393128 |
| evaluation of vero cell lysate antigen for the elisa of flaviviruses. | the vero cell lysate antigen for the enzyme-linked immunosorbent assay (elisa) of flaviviruses was evaluated for sensitivity, specificity including cross-reactions, and background by comparing with the standard elisa. human sera, in serial dilutions, were taken from subjects 14, 35, and 210 days postvaccination with 17d antigen. early after injection, high sensitivity (82.9%) was shown by the cell lysate antigen method. late after infection, high sensitivity was achieved by the standard method ( ... | 1993 | 8395596 |
| hepatitis c virus ns3 protein polynucleotide-stimulated nucleoside triphosphatase and comparison with the related pestivirus and flavivirus enzymes. | sequence motifs within the nonstructural protein ns3 of members of the flaviviridae family suggest that this protein possesses nucleoside triphosphatase (ntpase) and rna helicase activity. the rna-stimulated ntpase activity of this protein from prototypic members of the pestivirus and flavivirus genera has recently been established and enzymologically characterized. here, we experimentally demonstrate that the ns3 protein from a member of the third genus of flaviviridae, human hepatitis c virus ... | 1993 | 8396675 |
| a novel recombinant adenovirus vector expressing a flavivirus non-structural protein protects against lethal flavivirus challenge. | 1993 | 8403779 | |
| mutagenesis of the yellow fever virus ns2b protein: effects on proteolytic processing, ns2b-ns3 complex formation, and viral replication. | to study the role of specific regions of the yellow fever virus ns2b protein in proteolytic processing and association with the ns3 proteinase domain, a series of mutations were created in the hydrophobic regions and in a central conserved hydrophilic region proposed as a domain important for ns2b function. the effects of these mutations on cis cleavage at the 2b/3 cleavage site and on processing at other consensus cleavage sites for the ns3 proteinase in the nonstructural region were then chara ... | 1993 | 8411382 |
| synthesis of dengue virus rna in vitro: initiation and the involvement of proteins ns3 and ns5. | an assay for flavivirus rna-dependent rna polymerase activity in vitro was established using extracts of vero cells infected with dengue virus type 2 (den-2) or kunjin virus (kun). rna synthesis was initiated on a template of viral replicative form (rf) and rf was converted to the replicative intermediate (ri). the rna-dependent rna polymerase complex of den-2 utilised either den-2 or kun rf as template, and similarly the kun polymerase complex utilised either den-2 or kun rf template. in additi ... | 1993 | 8418788 |
| mutagenesis of conserved residues at the yellow fever virus 3/4a and 4b/5 dibasic cleavage sites: effects on cleavage efficiency and polyprotein processing. | flavivirus proteins are produced by co- and post-translational proteolytic processing of a large polyprotein using both host- and virus-encoded enzymes. the flavivirus serine proteinase, which consists of ns2b and ns3, is responsible for cleavages of at least four dibasic sites in the nonstructural region. in this study, a number of substitutions for the conserved amino acids flanking the 3/4a and 4b/5 dibasic cleavage sites [arg(p2)-arg(p1) decreases gly(p1')] were examined for their effects on ... | 1993 | 8421901 |
| processing of the dengue virus type 2 proteins prm and c-prm. | a glycoprotein c-prm of 35,000 m(r) was immuno-precipitated from lysates of aedes albopictus cells infected with dengue virus type 2 (den-2) using antisera directed against the c protein or an amino-terminal fragment of the prm glycoprotein. c-prm was not detected in infected vero cells. the prm glycoprotein synthesized in infected a. albopictus and vero cells was cleaved to produce the membrane-associated virion protein (m) and the non-m fragment (pr) immediately preceding or occurring simultan ... | 1993 | 8429301 |
| proper maturation of the japanese encephalitis virus envelope glycoprotein requires cosynthesis with the premembrane protein. | the role of the japanese encephalitis virus (jev) premembrane (prm) protein in maturation of the envelope (e) glycoprotein was evaluated by using recombinant vaccinia viruses encoding e in the presence (vp829) or absence (vp658) of prm. immunofluorescence analyses showed that e appeared to be localized in the endoplasmic reticulum of cells infected with jev, vp829, or vp658. however, reactivity with monoclonal antibodies and behavior in triton x-114 indicated that e produced in the absence of pr ... | 1993 | 8437237 |
| cleavage at a novel site in the ns4a region by the yellow fever virus ns2b-3 proteinase is a prerequisite for processing at the downstream 4a/4b signalase site. | flavivirus proteins are produced by co- and posttranslational proteolytic processing of a large polyprotein by both host- and virus-encoded proteinases. the viral serine proteinase, which consists of ns2b and ns3, is responsible for cleavage of at least four dibasic sites (2a/2b, 2b/3, 3/4a, and 4b/5) in the nonstructural region. since the amino acid sequence preceding ns4b shares characteristics with signal peptides used for translocation of nascent polypeptides into the lumen of the endoplasmi ... | 1993 | 8445732 |
| dengue 2 virus ns2b and ns3 form a stable complex that can cleave ns3 within the helicase domain. | flavivirus genomic rna is translated into a large polyprotein that is processed into structural and nonstructural proteins. the n-termini of several nonstructural proteins are produced by cleavage at dibasic sites by a two-component viral proteinase consisting of ns2b and ns3. ns3 contains a trypsin-like serine proteinase domain at its n-terminus, whereas the function of ns2b in proteolysis is yet to be determined. we have used an ns3-specific antiserum, under nondenaturing conditions, to demons ... | 1993 | 8460492 |
| detection of west nile virus by the polymerase chain reaction and analysis of nucleotide sequence variation. | a polymerase chain reaction (pcr) assay was developed to rapidly detect and identify west nile (wn) virus. the rna from seven isolates of wn virus from six countries and four other flaviviruses (kunjin, japanese encephalitis, st. louis encephalitis, and yellow fever viruses) was reverse-transcribed (rt) and amplified by pcr. the nucleotide sequences of the amplified products were determined by a rapid, automated dna sequencing method. the wn virus rt/pcr assay detected the target gene segment of ... | 1993 | 8470779 |
| [in vitro suppression of translation of tick-borne encephalitis virus rna using antisense nucleotides]. | effect of antisense oligodeoxyribonucleotides on in vitro translation of rnas corresponding to fragments of the tick-borne encephalitis virus genome has been investigated. sequences optimal for oligonucleotide binding and translation arrest have been identified. the most efficient oligonucleotide (17-mer) at a concentration of 2.5 microm completely arrests translation of the rna coding for the ns3 protein. | 1993 | 8487765 |
| nucleotide sequence of the envelope protein of a turkish isolate of tick-borne encephalitis (tbe) virus is distinct from other viruses of the tbe virus complex. | turkish tick-borne encephalitis (tte) virus causes an acute form of meningoencephalomyelitis in sheep in the north-western region of turkey. the clinical syndrome resembles louping ill (li) and the viruses responsible for both li and tte are members of the tick-borne encephalitis (tbe) complex of the flaviviridae. the envelope protein gene of tte virus was reverse-transcribed, amplified, cloned and sequenced. alignment of the resultant sequence with those from other viruses of the tbe complex re ... | 1993 | 8492100 |
| the fc portion of antibody to yellow fever virus ns1 is a determinant of protection against yf encephalitis in mice. | the mechanism by which antibodies to the flavivirus nonvirion protein ns1 protect mice against encephalitis is unknown but their binding to cell surface ns1 raises the possibility of involvement of an fc piece-directed immune function. to investigate this, we prepared the f(ab')2 moiety of a protective igg2a monoclonal antibody (mab) against yellow fever virus (yf) ns1 and isolated igg2a- and igg2b-secreting isotype switch variants from a hybridoma that secretes a nonprotective igg1 anti-yf ns1 ... | 1993 | 8517015 |
| regulation of the late events in flavivirus protein processing and maturation. | in order to determine the requirements for secretion of flavivirus structural proteins, we analyzed the expression of several west nile flavivirus gene cassettes of different lengths in vaccinia virus expression systems. expression of the longest cassette coding for the 5'-nontranslated region, proteins c through ns2b, and the protease domain of ns3, resulted in secretion of prm-e complexes and cleavage of prm. the presence and proper processing of the ns2a-ns2b-ns3 region appeared to be necessa ... | 1993 | 8517028 |
| west nile virus (flaviviridae:flavivirus) in experimentally infected argas ticks (acari:argasidae). | to better define the possible role of argasid ticks in the epidemiology of west nile virus, adult argas arboreus, a. persicus, and a. hermanni were fed through a membrane on fetal bovine serum containing 10(5.5) 50% tissue culture infective doses (tcid50)/ml of west nile virus. the virus was detected for three and four days after feeding in a. persicus and a. hermanni, respectively. the virus titers then decreased to undetectable levels in both species. when the infective dose was increased to 1 ... | 1993 | 8517492 |
| phylogenetic relationships of dengue-2 viruses. | rna oligonucleotide fingerprinting studies on a large number of virus isolates previously demonstrated considerable genetic variation in isolates of dengue (den)-2 serotype. we report the entire envelope (e) glycoprotein gene and deduced amino acid sequences of 16 den-2 viruses and the phylogenetic relationships of these, plus 17 additional published den e gene sequences. comparison of den-2 e glycoprotein gene sequences revealed base substitutions scattered throughout the entire gene with as mu ... | 1993 | 8212556 |
| wesselsbron virus haemagglutination: studies with erythrocytes of various animal species at different ph and temperatures. | the haemagglutinating (ha) properties of the nigerian strain of wesselsbron virus have been investigated using erythrocytes from a wide range of animals. the results showed that wesselsbron virus possesses ha activity when extracted using the sucrose and acetone method. the erythrocytes of goose, horse, donkey, pig, cattle, sheep, goat, monkey, man, rabbit, rat, guinea pig and chicken were agglutinated by wesselsbron virus at different ph values (5.75-7.0) and temperatures of 4 degrees c, room ( ... | 1993 | 8380321 |
| presence of viral replicative intermediates in the liver and serum of patients infected with hepatitis c virus. | hepatitis c virus (hcv) is a positive-polarity, single-stranded rna virus, distantly related to the pestivirus and flavivirus genera. these viruses replicate through the formation of a minus-strand rna intermediate, which encodes the positive-strand genome, which is subsequently encapsidated, enveloped, and released from infected cells. minus-strand rna is not found in the mature, circulating virions of flaviviruses. in an attempt to study the relative amounts of viral plus and minus strand in t ... | 1993 | 8387574 |
| completion of kunjin virus rna sequence and recovery of an infectious rna transcribed from stably cloned full-length cdna. | completion of the kunjin virus (kun) rna sequence showed that it is the longest flavivirus sequence reported (11,022 bases), commencing with a 5' noncoding region of 96 bases. the 3' noncoding sequence of 624 nucleotides included a unique insertion sequence of 46 bases adjacent to the stop codon, but otherwise it had properties similar to those of rnas of closely related flaviviruses. a full-length kun cdna clone which could be stably propagated in escherichia coli dh5 alpha was constructed; sp6 ... | 1994 | 8207832 |
| mapping the flv locus controlling resistance to flaviviruses on mouse chromosome 5. | genetically determined resistance to flaviviruses in mice is a dominant trait conferred by alleles at a single autosomal locus designated flv, but no gene products have been associated with this locus and the mechanism of resistance is not well understood. to further characterize this model of genetic resistance, we conducted mapping studies to determine the chromosomal location of flv. because of evidence suggesting that the flv locus is on chromosome 5, three-point backcross linkage analyses w ... | 1994 | 8254755 |
| structural changes and functional control of the tick-borne encephalitis virus glycoprotein e by the heterodimeric association with protein prm. | we have used tick-borne encephalitis virus to study the involvement of acidic compartments during the entry and release phases of flavivirus infection and to elucidate the role of protein prm in immature virions. elevation of the ph in acidic intracellular compartments by either bafilyomycin a1, a specific inhibitor of the vacuolar type h(+)-atpase or by nh4cl had a strong inhibitory effect during virus penetration and also prevented the cleavage of prm when added in the late phase of the viral ... | 1994 | 8259646 |
| analysis of the structural protein gene sequence shows kyasanur forest disease virus as a distinct member in the tick-borne encephalitis virus serocomplex. | kyasanur forest disease (kfd) virus is a highly pathogenic member of the family flaviviridae producing a haemorrhagic disease in infected human beings. despite this high pathogenicity and potential epidemiological importance, there have been relatively few detailed antigenic or molecular studies on kfd virus. the nucleotide sequences of the genes encoding the structural proteins of the virus have now been determined. from these data we conclude that kfd virus is a distinct member in the tick-bor ... | 1994 | 8113732 |
| geographic distribution and evolution of yellow fever viruses based on direct sequencing of genomic cdna fragments. | we have compared the nucleotide sequence of an envelope protein gene fragment encoding amino acids 291 to 406 of 22 yellow fever (yf) virus strains of diverse geographic and host origins isolated over a 63 year time span. the nucleotide fragment of viral rna was examined by direct sequencing of a pcr product derived from complementary dna. alignment with the prototype asibi strain sequence showed divergence of 0 to 21.5% corresponding to a maximum of 5.2% divergence in the amino acid sequence. t ... | 1994 | 8113765 |
| medically important arboviruses of the united states and canada. | of more than 500 arboviruses recognized worldwide, 5 were first isolated in canada and 58 were first isolated in the united states. six of these viruses are human pathogens: western equine encephalitis (wee) and eastern equine encephalitis (eee) viruses (family togaviridae, genus alphavirus), st. louis encephalitis (sle) and powassan (pow) viruses (flaviviridae, flavivirus), lacrosse (lac) virus (bunyaviridae, bunyavirus), and colorado tick fever (ctf) virus (reoviridae, coltivirus). their scien ... | 1994 | 8118792 |
| recombinant vaccinia viruses co-expressing dengue-1 glycoproteins prm and e induce neutralizing antibodies in mice. | four recombinant vaccinia viruses expressing different portions of the dengue type 1 virus (den-1) genome (c-prm-e-ns1-ns2a-ns2b; prm-e; prm-e-ns1-ns2a-ns2b; or ns1-ns2a) were constructed in order to establish the most immunogenic configuration of den-1 proteins. both recombinants producing prm and e in the absence of c induced the synthesis of extracellular forms of e in vitro. mice inoculated with these two recombinants produced den-1 neutralizing (neut) and haemagglutination inhibiting (hai) ... | 1994 | 8165861 |
| both ns3 and ns4a are required for proteolytic processing of hepatitis c virus nonstructural proteins. | the proteolytic cleavages at the ns3-ns4a, ns4a-ns4b, ns4b-ns5a, and ns5a-ns5b junctions of hepatitis c virus (hcv) polyprotein are effected by the virus-encoded serine protease contained within ns3. using transient expression in hela cells of cdna fragments that code for regions of the hcv polyprotein, we studied whether viral functions other than ns3 are required for proteolytic processing at these sites. we found that, in addition to ns3, a c-terminal 33-amino-acid sequence of the ns4a protei ... | 1994 | 8189513 |
| first isolations of arboviruses from phlebotomine sand flies in west africa. | for the first time in west africa, arboviruses were isolated from phlebotomine sand fly pools. one strain of chandipura virus (a vesiculovirus), four strains of saboya virus (a flavivirus), and one strain of a not yet identified virus were isolated. three hundred twenty-two pools were established from a population of 33,917 sand flies caught in co2 light traps in the ferlo sahelian region of senegal from november 1991 to december 1992. this is the first isolation of chandipura virus from any art ... | 1994 | 8203705 |
| ns2b-3 proteinase-mediated processing in the yellow fever virus structural region: in vitro and in vivo studies. | several of the cleavages required to generate the mature nonstructural proteins from the flaviviral polyprotein are known to be mediated by a complex consisting of ns2b and a serine proteinase domain located in the n-terminal one-third of ns3. these cleavages typically occur after two basic residues followed by a short side chain residue. cleavage at a similar dibasic site in the structural region is believed to produce the c terminus of the virion capsid protein. to study this cleavage, we deve ... | 1994 | 8189517 |
| [what is the status of immune prevention of "tick bite diseases"?]. | 1994 | 8147025 | |
| [tick-borne encephalitis in central europe: a rare cause of autochthonous meningo-encephalo-myelitis]. | 1994 | 8140082 | |
| expression of cloned envelope protein genes from the flavivirus tick-borne encephalitis virus in mammalian cells and random mutagenesis by pcr. | the structural membrane proteins prm and e of the flavivirus tick-borne encephalitis (tbe) virus were expressed in mammalian cells for the purpose of probing the structure and molecular interactions of these proteins. advantage was taken of the natural error frequency of the taq polymerase used in the pcr amplification to generate a randomly mutated population of genes that were then cloned directly into plasmid expression vectors under the control of an sv40 promoter. analysis of the mutation f ... | 1994 | 7975266 |
| a case of japanese encephalitis. | we report a case of japanese encephalitis that occurred in a woman who had spent only a few days in an area where she could have been exposed to the virus. the risks and protective efficacy of vaccination against japanese encephalitis virus for travellers who visit endemic areas for only a short period are discussed. | 1994 | 8034997 |
| kinetic and structural analyses of hepatitis c virus polyprotein processing. | recombinant vaccinia viruses were used to study the processing of hepatitis c virus (hcv) nonstructural polyprotein precursor. hcv-specific proteins and cleavage products were identified by size and by immunoprecipitation with region-specific antisera. a polyprotein beginning with 20 amino acids derived from the carboxy terminus of ns2 and ending with the ns5b stop codon (amino acids 1007 to 3011) was cleaved at the ns3/4a, ns4a/4b, ns4b/5a, and ns5a/5b sites, whereas a polyprotein in which the ... | 1994 | 8035505 |
| use of a flavivirus rna-dependent rna polymerase assay to investigate the antiviral activity of selected compounds. | we have developed an assay using flavivirus rna-dependent rna polymerase to test the inhibitory activity of potential antiviral agents. the effects of antiviral agents on rna synthesis were examined in this assay using extracts of vero cells infected with dengue virus type 2 or kunjin virus. several different classes of known polymerase inhibitors were tested. the synthesis of double-stranded replicative form rna was inhibited in a dose-dependent fashion in the presence of the polyoxometalate hp ... | 1994 | 7993077 |
| [flavivirus encephalitis in an urban area]. | 1994 | 8029200 | |
| arboviruses causing human disease in the australasian zoogeographic region. | over 65 arboviruses have been reported from countries in the australasian zoogeographic region, but only a few have been implicated in human disease. these include the flaviviruses murray valley encephalitis (mve), kunjin (kun), kokobera (kok), and dengue, particularly types 1 and 2; the alphaviruses ross river (rr), barmah forest (bf), and sindbis (sin); and the bunyaviruses, gan gan and trubanaman. in this paper recent epidemiological and clinical results pertaining to these viruses are review ... | 1994 | 8031248 |
| processing of dengue type 4 and other flavivirus nonstructural proteins. | dengue type 4 (den4) and other flaviviruses employ host and viral proteases for polyprotein processing. most proteolytic cleavages in the den4 nonstructural protein (ns) region are mediated by the viral ns2b-ns3 protease. the n-terminal third of ns3, containing sequences homologous to serine protease active sites, is the protease domain. to determine required sequences in ns2b, deletions were introduced into den4 ns2b-30% ns3 cdna and the expressed polyproteins assayed for self-cleavage. a 40 am ... | 1994 | 8032267 |
| processing of the intracellular form of the west nile virus capsid protein by the viral ns2b-ns3 protease: an in vitro study. | according to the existing model of flavivirus polyprotein processing, one of the cleavages in the amino-terminal part of the flavivirus polyprotein by host cell signalases results in formation of prm (precursor to one of the structural proteins, m) and the membrane-bound intracellular form of the viral capsid protein (cint) retaining the prm signal sequence at its carboxy terminus. this hydrophobic anchor is subsequently removed by the viral protease, resulting in formation of the mature viral c ... | 1994 | 8057458 |
| [a serological survey regarding flaviviridae infections on the island of réunion (1971-1989)]. | serological prevalence of flaviviridae was studied on reunion island by testing 2,507 human sera from a randomised sample. each serum was tested against 5 viruses (yellow fever, dengue type 1 and 2, west nile and wesselsbron) using haemagglutination inhibition test: 42.68% of human sera were found positive. the multivalent reactions represent practically three fourths of the positive ones. a severe dengue type 2 outbreak on the island in 1977-1978 and the possible circulation of a flavivirus may ... | 1994 | 8061530 |
| postvaccinal plexus neuropathy following vaccination against tick-borne encephalitis and tetanus in a competitive athlete. | 1994 | 8086776 | |
| processing of flavivirus structural glycoproteins: stable membrane insertion of premembrane requires the envelope signal peptide. | the flavivirus structural proteins capsid (c), premembrane (prm), and envelope (e) are cleaved in that order from the n-terminus of the polyprotein by the er intralumenal enzyme signal peptidase. the prm-e and e-ns1 junctions contain hydrophobic domains with both transmembrane and signal function. these domains reside at the c-termini of prm and e, respectively, after cleavage. we studied the functions of the 37-amino-acid c-terminus of the dengue virus type 4 (den4) prm (amino acids 243-279 of ... | 1994 | 7941319 |
| flavivirus west nile (sarafend) egress at the plasma membrane. | west nile (sarafend) virus was distinctly observed to bud from the plasma membrane rather than mature intracellularly. this has been observed with transmission electron microscopy. using conventional scanning electron microscopy, budding at the plasma membrane especially at the filopodia was clearly illustrated. immunogold labelling against the virus envelope protein was also performed to confirm this mode of exit. the gold particles were observed to be located at the sites where virus budding w ... | 1994 | 7944952 |
| [differences in susceptibility to peripheral infection with japanese encephalitis virus among inbred strains of mouse]. | we compared susceptibility of inbred mouse strains against intracerebral as well as peripheral challenge of a flavivirus, japanese encephalitis (je) virus, and the results were summarized as follows: (1) seven inbred mouse strains (c3h/he, c57bl/6, balb/c, akr/n, nc, nzb, dba/2) could be classified into following 3 groups by their mortality and infection rate when they were subcutaneously challenged with a wild je virus strain isolated from field-caught mosquitoes at a single passage in mouse (b ... | 1994 | 7900284 |
| generation of long flavivirus expression cassettes by in vivo recombination and transient dominant selection. | assembly of expression cassettes coding for large segments of viral polyproteins is often complicated or impossible due to the instability of the resulting recombinant (re-) plasmids during propagation in escherichia coli. using the transient dominant selection approach described for the construction of vaccinia virus recombinants (re-vv), we have constructed several intermediate vectors and developed a procedure which enables direct assembly of long expression cassettes in the vv genome by in v ... | 1994 | 7958993 |
| dengue fever virus and japanese encephalitis virus synthetic peptides, with motifs to fit hla class i haplotypes prevalent in human populations in endemic regions, can be used for application to skin langerhans cells to prime antiviral cd8+ cytotoxic t cells (ctls)--a novel approach to the protection of humans. | flaviviruses were reported to induce cd8+ cytotoxic t cells in infected individuals, indicating that nonapeptides, proteolytic cleavage products of the viral precursor protein, enter the endoplasmic reticulum in infected cells and interact with hla class i molecules. the assembled hla class i molecules are transported to the plasma membrane and prime cd8+ t cells. current knowledge of the interaction of viral peptides with hla molecules is reviewed. based on this review, an idea is presented to ... | 1994 | 7871759 |
| the interactions of the flavivirus envelope proteins: implications for virus entry and release. | viral membrane proteins play an important role in the assembly and disassembly of enveloped viruses. oligomerization and proteolytic cleavage events are involved in controlling the functions of these proteins during virus entry and release. using tick-borne encephalitis virus as a model we have studied the role of the flavivirus envelope proteins e and prm/m in these processes. experiments with acidotropic agents provide evidence that the virus is taken up by receptor-mediated endocytosis and th ... | 1994 | 7913359 |
| detection of transfusion-associated hepatitis caused by non-a, non-b, non-c flavivirus. | sera of patients suffering from acute hepatitis, and different forms of chronic hepatitis were found to be reactive to reagents prepared from the yellow fever virus (yf) vaccine strain. serum samples of 1974 patients were tested, and 133 of them were positive. hepatitis c virus specific antibodies were absent from the majority of them. the frequency of antibodies to other flaviviruses (tick-borne encephalitis, west nile) and hepatitis b virus markers was similar to that measured among the popula ... | 1994 | 7921854 |
| kinetics and cross-reactivity of the virus-specific antibody-forming cells in mice during primary and secondary infection with japanese encephalitis virus and related flaviviruses. | a modified antibody-forming cell assay was used to enumerate splenocytes secreting antibodies to japanese encephalitis (je) virus and four other flaviviruses in infected cells as the target antigens. the optimal viral antigen expression for the assay was standardized in the infected cells for each virus and the incubation time varied depending of the cell line and the virus. the kinetics of response of je virus-infected mice readily showed igg isotype switching. antibody-forming splenocytes of m ... | 1994 | 7962258 |