Publications

characterization of the mesenteronal infection with western equine encephalomyelitis virus in an incompetent strain of culex tarsalis.	interactions of western equine encephalomyelitis (wee) virus are compared with mesenterons of 2 genetically selected susceptible (ws) and refractory (wr) lines of culex tarsalis. both ws and wr females had similar susceptibility when parenterally inoculated with virus, thus it was initially thought that resistance in wr cx. tarsalis was associated with a mesenteronal infection barrier. present data on viral growth in mesenterons dissected from females fed on virus-soaked pledgets suggest that vi ...	1989	2774065
dengue virus, a flavivirus, propagates in human bone marrow progenitors and hematopoietic cell lines.	dengue and other arbovirus diseases are frequently associated with bone marrow failure. we show that dengue type 4 (den4) propagates in colonies derived from immature human bone marrow progenitors. den4 was propagated in bfu-e-derived colonies and replication was dependent on erythropoietin. den4 was not cytotoxic. in inoculated cultures, diffuse bursts with many clusters contained large amounts of den4 rna. in contrast to dengue infection of macrophages, virus propagation in semisolid culture w ...	1989	2765663
[arbovirus transmission cycles in madagascar].	some arboviruses are highly pathogenic for men or animals, arboviruses epidemiological patterns in madagascar were determined by entomological, serological, and virological surveys. we listed potentials arboviruses vectors in madagascar. entomological results generated by us during five years, as well as prior to, are shown. we caught more than 150,000 hematophagous arthropods, belonging to 107 species at least. 3 of these species were new. 4183 inoculation pools were done. we studied serologica ...	1989	2751393
cell-associated west nile flavivirus is covered with e+pre-m protein heterodimers which are destroyed and reorganized by proteolytic cleavage during virus release.	flaviviruses are enveloped viruses which accumulate in cellular vacuoles prior to release. the membrane of cell-associated virus contains the proteins pre-m and e. during release of virus the pre-m protein is cleaved, and only its carboxy-terminal segment remains associated with the virus as m protein. studies of the association of membrane proteins of intracellular and extracellular particles of west nile virus show that in cell-associated virus the pre-m and e proteins are present as e+pre-m h ...	1989	2724410
analyses of the terminal sequences of west nile virus structural proteins and of the in vitro translation of these proteins allow the proposal of a complete scheme of the proteolytic cleavages involved in their synthesis.	the proteolytic processes involved in the synthesis of the structural proteins of the west nile (wn) flavivirus were analyzed: the carboxy-terminal sequences of the structural proteins were determined and the proteins translated in vitro in the presence of membranes from a mrna coding for the structural polyprotein were analyzed. the results obtained indicate that the following proteolytic activities are involved in the synthesis and assembly of wn virus structural proteins: the growing peptide ...	1989	2705302
[mac-elisa for the detection of igm antibodies to dengue type i virus (rapid diagnosis of dengue type i virus infection)].	the commercial rapid diagnostic reagents for dengue virus infection is still not available at present. an abc mac-elisa (avidin biotin complex igm antibody capture enzyme linked immunosorbent assay) for the detection of dengue type i virus infection has been described. igg purified from high titer (hi = 2560) human anti-flavivirus serum is labelled with biotin for the rapid diagnosis of dengue type i virus infection. 389 serum specimens of suspected dengue fever patients including 226 hi(+) pair ...	1989	2700156
characterization of japanese encephalitis virus envelope protein expressed by recombinant baculoviruses.	recombinant baculoviruses containing the coding sequences of the viral structural proteins, i.e., the capsid (c) protein, the precursor to premembrane (prem) protein, and the envelope (e) protein, as well as a nonstructural protein, ns1, of japanese encephalitis virus (jev) were constructed. infection of spodoptera frugiperda cells with these recombinant viruses produced prem and e proteins. the e proteins synthesized by the recombinants were shown to be glycosylated and similar in size to the a ...	1989	2688300
detection of viral infection by immunofluorescence in formalin-fixed tissues, pretreated with trypsin.	the presence of viral antigen in sections from formalin-fixed and paraffin-embedded human tissues was demonstrated by trypsin digestion followed by direct or indirect immunofluorescence. the specimens may be used for retrospective diagnosis. the immunofluorescence technique has to be adapted to the suspected virus infection on the basis of previous histopathologic study. variations of trypsin concentration time and temperature of incubation, expose different viral antigens and have to be previou ...	1988	2687623
[significance of igm titration by an immunoenzyme technic for the serodiagnosis and epidemiological surveillance of dengue in french polynesia].	the usefulness of igm antibody capture enzyme-linked immunosorbent assay (elisa-igm) for the diagnosis of dengue was studied using several groups of sera. an attempt was made to detect igm against each dengue serotype. of 76 paired sera from patients with dengue type 4 infection, the diagnosis was confirmed by elisa-igm in 74: in 47 out of 49 primary dengue infections and in all 27 secondary dengue infections. it was possible to detect igm in 15 of the acute sera of primary infections and in 16 ...	1989	2667066
clinical, clinicopathologic, and hematologic features of kyasanur forest disease.	in 1957, a fatal disease occurred among monkeys in a forested area of shimoga district, karnataka state, india. concurrently, there was an outbreak of febrile, occasionally fatal illness among people living in the vicinity. the disease was caused by a new tick-borne flavivirus belonging to the russian spring-summer encephalitis complex of viruses. the early clinical description of the disease included severe cases with hemorrhagic manifestations, including intermittent epistaxis, hematemesis, me ...	1989	2665018
epitopic analysis of antigenic determinants on the surface of dengue-2 virions using monoclonal antibodies.	the relative binding sites of dengue serotype-specific, dengue subcomplex-specific, dengue complex-specific, flavivirus subgroup-reactive, and flavivirus group-reactive monoclonal antibody preparations were identified by using competitive antibody binding assays. a dengue complex-specific epitope, capable of mediating infection enhancement, was identified on a 20,000 dalton protein found on intracellular virions. the other epitopes were assigned relative positions on the e glycoprotein by compet ...	1985	2578750
replication strategy of kunjin virus: evidence for recycling role of replicative form rna as template in semiconservative and asymmetric replication.	only three forms of kunjin virus-specified rna were isolated from cytoplasm early after the latent period (about 15 hr) viz., 44 s genomic-sized single-stranded rna, 20 s double-stranded "replicative form" (rf), and 20-28 s partially ribonuclease-resistant (about 70%) "replicative intermediate" (ri). the rf and ri were resolved by electrophoresis in aqueous-agarose gel only following licl fractionation. the ri did not enter urea-polyacrylamide gels. after denaturation of untreated or rnase-treat ...	1985	2578239
[transmission cycles of arboviruses in madagascar].	some arboviruses are highly pathogenic for men or animals. arboviruses epidemiological patterns in madagascar were determined by entomological, serological, and virological surveys. we listed potentials arboviruses vectors in madagascar. entomological results generated by us during five years, as well as prior to, are shown. we caught more than 150,000 hematophagous arthropods, belonging to 107 species at least. 3 of these species were new. 4183 inoculation pools were done. we studied serollogic ...	1989	2576622
enzyme immunoassay for the detection of dengue igg and igm antibodies using infected mosquito cells as antigen.	the detection of immunoglobulin (ig)g and igm antibodies to dengue 1 virus was studied by a simple enzyme immunoassay, in which infected cultured cells infected with dengue virus were used as antigen (eia-icc). detection of anti-dengue 1 igg by eia-icc was correlated with haemagglutination assays. eia-icc anti-dengue 1 igm detection was less sensitive than igm capture enzyme-linked immunosorbent assay. igg and igm responses in dengue 1 infection were studied by eia-icc, using sera collected at d ...	1989	2575811
japanese encephalitis after a two-week holiday in bali.	japanese encephalitis is described in a 10-year-old girl after a short holiday in bali. four days after returning to australia the patient presented with a high fever, stupor and rapidly-developing focal neurological signs. recovery occurred gradually over a period of three months and she has returned to school. japanese encephalitis viral infection was confirmed by a marked rise in specific haemagglutination-inhibition antibodies and the presence of immunoglobulin m antibodies to the flavivirus ...	1989	2566108
wesselsbron virus infection in west african dwarf goats (fouta djallon): virological and immunological studies.	west african dwarf goats were experimentally infected with nigerian strain of wesselsbron virus. viraemia was detected in infected goats 2 days after infection and lasted for one day. a 100% mortality was observed among the infected animals; the virus was reisolated in mice from almost every tissue obtained from the bodies of infected goats. in addition, the infected goats developed complement-fixing and haemagglutination inhibiting antibodies to wesselsbron virus.	1989	2565679
a rapid method for detection of flavivirus antigens: staphylococcal co-agglutination test using monoclonal antibodies to japanese encephalitis virus.	staphylococcus aureus rich in protein a when coated with monoclonal antibodies (moab) to japanese encephalitis virus (jev) gave a highly specific reaction with flavivirus antigens. the bacteria coated with jev species-specific moab gave a strong co-agglutination with fifty-six jev isolates from various parts of china, but no co-agglutination with murray valley encephalitis (mve) and kunjin (kun) virus antigens. the flavivirus- and subgroup-specific moabs were reactive with mve and kun, as well a ...	1989	2565671
flavivirus entry into cultured mosquito cells and human peripheral blood monocytes.	the entry modes of japanese encephalitis (je) and dengue-2 (den-2) viruses into c6/36 mosquito cells and of den-2 virus into human peripheral blood monocytes in vitro were studied. inoculation of either je or den-2 virions into c6/36 cells resulted in direct penetration of the virions into the cytoplasm at the cell surface in 3 stages. at stage 1, virions attached to the plasma membrane of host cells by their envelope spikes; at stage 2, the virion envelopes approximated to and eventually overla ...	1989	2564270
maintaining mosquito cell lines at high temperatures: effects on the replication of flaviviruses.	the upper thermal limit for maintenance of eleven mosquito cell lines was studied. although most cell lines could be grown at 32 degrees c to 34 degrees c, anopheles stephensi cell line could be maintained at 37 degrees c. at higher temperatures initial growth rate was higher, but yield of cells after about a week of incubation was lower than at the standard temperature (28 degrees c). replication of several flaviviruses in aedes albopictus cell cultures adapted to 34.5 degrees c was faster, and ...	1989	2563994
rearing temperature influences flavivirus vector competence of mosquitoes.	culex annulirostris skuse mosquitoes (brisbane strain) were reared at 20 degrees c or 27 degrees c and the adult females were experimentally infected by feeding murray valley encephalitis virus (mve). they were then maintained (a) in the insectary at 20 degrees c, after rearing at either 20 degrees c or 27 degrees c; (b) at ambient outdoor temperatures, range 12.2-28.9 degrees c, mean 19.6 degrees c; or (c) at 27 degrees c after rearing at 27 degrees c. there was no significant difference in rat ...	1989	2562419
the vector competence of culex annulirostris, aedes sagax and aedes alboannulatus for murray valley encephalitis virus at different temperatures.	culex annulirostris skuse, colonized from brisbane, queensland, and mildura, victoria, australia, were effective vectors of murray valley encephalitis virus at 20, 27 and 32-35 degrees c with full extrinsic incubation periods of 15, 10 and 4 days respectively. at 20 degrees c, 7-11 days post-infection, transmission by the mildura colony (0-20%) was less efficient than the brisbane colony (30-70%) but both were capable of 75-100% transmission after longer extrinsic incubation periods. discriminan ...	1989	2562418
results of arbovirological examination of birds of the family hirundinidae in czechoslovakia.	migratory birds (swallow, hirundo rustica; sand martin, riparia riparia; house martin, delichon urbica) caught in southern moravia (czechoslovakia) in 1984-87 were examined for arbovirus infections. isolation experiments were carried out using blood samples of 183 birds (52 swallows, 107 sand martins, and 24 house martins). the results were negative. serological examinations of 136 birds (36 swallows, 86 sand martins, and 14 house martins) were made by haemagglutination-inhibition test (hit) usi ...	1989	2562171
[serologic study of arbovirus in 2 localities of the juventud island].	a serologic study is made in two population groups in the isle of youth. a total 268 blood samples in blotting paper are subjected to the hemagglutination inhibition technique, using the eastern equine encephalomyelitis, western equine encephalomyelitis, saint louis encephalitis, and dengue 2 viruses; 16% positivity to flavivirus was found. a second serum sample was taken in people positive by the hemagglutination inhibition technique in order to carry out the techniques of complement fixation a ...	1989	2561798
[a seroepidemiologic and virological study of the presence of arboviruses in moldavia in 1961-1982].	in romania, st. drăgănescu et al., miszkolczy et al., based on clinical and epidemiological observations, affirmed the possible presence of "tick-borne encephalitis (tbe)". however, critical retrospective evaluation of certain others' papers published through 1958-1971 reveal some uncommon features. by way of example: a very high incidence of cf- and hi-antibodies in acute and chronic cns illnesses as well as in general population; replication in nucleus and maturation in mitochondria of a strai ...	1989	2561524
[morphological study of omsk hemorrhagic fever (ohf) virus with the electron microscope].	morphological characterization of ohf virus was studied by means of thin section electron microscopy in the brains of mice infected with omsk hemorrhagic fever virus. the crystals, microvesicles, vacuoles and as beehive structures were observed in the virus-infected cells. the possible relationship between the characteristic structures and virus morphogenesis is discussed. it is indicated that these characteristic structures may be important to morphological characterization of ohf virus.	1989	2561476
[the possibility of preparing a live vaccine against tick-borne encephalitis from malay langat virus tp-21].		1989	2560847
arbovirus infections and viral haemorrhagic fevers in uganda: a serological survey in karamoja district, 1984.	sera collected in may 1984 from 132 adult residents of karamoja district, uganda, were examined by haemagglutination inhibition tests for antibodies against selected arboviruses, namely chikungunya and semliki forest alphaviruses (togaviridae); dengue type 2, wesselsbron, west nile, yellow fever and zika flaviviruses (flaviviridae); bunyamwera, ilesha and tahyna bunyaviruses (bunyaviridae); and sicilian sandfly fever phlebovirus (bunyaviridae); and by immunofluorescence tests against certain hae ...	1989	2559514
susceptibility of laboratory and domestic animals to experimental infection with potiskum virus.	the biological characteristics of potiskum virus, a hitherto undescribed virus isolated in nigeria from the liver of a giant rat (cricetomys gambianus), were studied by experimental infections of laboratory and domestic animals. the laboratory animal hosts used included mice, rats, rabbits and chicks. suckling and weaning mice succumbed to fatal infection when infected with potiskum virus by intracerebral or intraperitoneal routes. infected mice had high titres of virus and mild histopathologica ...	1989	2558278
[the effect of antigen-specific suppression induced by flaviviruses on the formation of an antigen-specific immunologic defect].	the effect of experimental flavivirus infection on the formation of antigen-induced immunosuppression in mice was studied. for this purpose, balb/c mice with asymptomatic infection caused by langat or west nile virus were inoculated with supraoptimal doses of sheep erythrocytes and then checked for the capacity to respond again with production of hemolysin-synthesizing cells to the challenge with the optimal dose of the same antigen. the effect of the antigen-induced immunosuppression was found ...	1989	2555964
homologous potyvirus and flavivirus proteins belonging to a superfamily of helicase-like proteins.	comparison of the nucleoside triphosphate-binding motif(ntbm)-containing proteins of two groups of apparently distantly related positive-strand rna viruses (potyvirus and flavivirus), revealed significant sequence similarity. in addition, these two groups of viral proteins show amino acid motifs in common with those conserved in a group of five ntbm-containing proteins from prokaryotic and eukaryotic cells, some of which have been experimentally related to helicase activity. here we propose that ...	1989	2555266
genome sequence of tick-borne encephalitis virus (western subtype) and comparative analysis of nonstructural proteins with other flaviviruses.	the genome sequence of tick-borne encephalitis (tbe) virus (western subtype vaccine strain neudoerfl) was determined. this extends the previously published sequence of the structural proteins to the nonstructural protein region and noncoding sequences at the 5'- and 3'-termini. the amino-termini of the individual proteins were assigned by comparison with other flavivirus sequences. amino acid homology calculations between tbe virus and mosquito-borne flaviviruses were performed for all nonstruct ...	1989	2554575
[recent occurrence of human infection by rocio arbovirus in the valley of ribeira region].	the presence of igm antibodies to rocio in sera of two children from rural area of ribeira valley, brazil, was detected by mac-elisa. this new arbovirus of the flaviviridae family was responsible for an extensive encephalitis epidemic that occurred in the region in 1975-1977. since 1980 no human disease caused by this virus has been diagnosed. an improvement on surveillance of rocio infections and on the researches for virus identification in suspected vectors and reservoirs is necessary.	1989	2554477
seroepidemiological study of japanese encephalitis in dimapur, nagaland.	a seroepidemiological study of japanese encephalitis (je) in dimapur, nagaland was carried out following an outbreak of the disease between july, 1985 and february, 1986. altogether 50 persons were affected with 30 (60 per cent) deaths. the attack and death rates per 1000 were more in nagas viz. 0.55 and 0.34 than non-nagas viz. 0.33 and 0.20 respectively. all ages and both sexes were affected. of the nine mosquito species encountered culex vishnui showed the highest density (44.5/mh). culture o ...	1989	2553798
the 3'terminus of lactate dehydrogenase-elevating virus genome rna does not contain togavirus or flavivirus conserved sequences.	lactate dehydrogenase-elevating virus (ldv) is currently considered to be an unclassified togavirus. the 3' terminus of the genome rna of the c-strain of ldv was cloned and sequenced. a synthetic dna oligomer complementary to the 3' portion of this cloned sequence was then used to prime dideoxy sequencing from the ldv-c genome rna as well as from the genome rnas of three additional ldv isolates. a high degree of sequence conservation was observed in the 3' terminal region among the four ldv isol ...	1989	2552663
morphogenesis of flaviviruses.		1989	2552624
larval diet and the vector competence of culex annulirostris (diptera: culicidae) for murray valley encephalitis virus.	culex annulirostris skuse larvae were reared on two different amounts of powdered dog chow and yeast, low intake (2.8 micrograms/larva) and high intake (8.4 micrograms/larva), to produce adults with mean wing lengths of 3.25 and 3.7 mm, respectively. the resulting adults were fed different dosages of murray valley encephalitis virus and after 10 d extrinsic incubation at 28 degrees c, the infection rate, transmission rate, salivary gland, and body titers were determined. there were no significan ...	1989	2552121
kunjin virus isolates of australia are genetically homogeneous.	the genomes of 22 isolates of kunjin virus (kun) from australia were characterized and compared using rnase t1 oligonucleotide fingerprinting. the results show that all isolates belonged to one topotype, the distribution of which covered the entire australian continent. this finding is similar to that of murray valley encephalitis virus, but in contrast to the results reported for some other flaviviruses such as saint louis encephalitis virus.	1989	2552010
carboxy-terminal analysis of nine proteins specified by the flavivirus kunjin: evidence that only the intracellular core protein is truncated.	nine proteins specified by kunjin virus were labelled with [3h]lysine and digested with carboxypeptidase b which specifically cleaves carboxy-terminal lys or arg. the theoretical amount of [3h]lysine was released from the non-structural (ns) proteins ns2a, ns2b, ns3 and ns4b, which have a common carboxy terminus lys-arg deduced from cleavage sites established in the viral polyprotein by previous n-terminal amino acid analyses. this is a flavivirus consensus site, always followed by gly, ala or s ...	1989	2549188
flavivirus infection: essential ultrastructural changes and association of kunjin virus ns3 protein with microtubules.	virus-induced vesicles evolved early in the kunjin virus replication cycle around 9 to 10 h p.i. just before the end of the latent period in infected vero cells. about 2 h following the appearance of the vesicles, microtubule paracrystals were also formed. these two virus-induced structures seemed interlinked and have essential roles in kunjin virus replication. a viral protein ns3 was found to be associated with the microtubule component of the cells. when vinblastine sulphate was added to the ...	1989	2548454
detection of a trypsin-like serine protease domain in flaviviruses and pestiviruses.	we propose through a sequence and structural-pattern analysis that a protein domain of undefined function encoded by the enveloped rna flavi- and pestivruses is a ser active-center enzyme related to the cellular trypsin family. a further homology is emphasized with the group of (cys active-center) viral proteases encoded by nonenveloped rna viruses of the picorna-, como-, nepo-, and potyvirus classes. structural modeling of the putative flaviviral protease domain suggests amino acids that are cr ...	1989	2548336
prospects for treatment of viral hemorrhagic fevers with ribavirin, a broad-spectrum antiviral drug.	ribavirin, a broad-spectrum antiviral drug, is active against hemorrhagic fever viruses (with the exception of ebola virus) in cell culture systems. in model infections with arenaviruses in guinea pigs and monkeys, ribavirin has demonstrated both prophylactic and therapeutic efficacy. in therapeutic studies it has not prevented late-onset neurologic disease. in human cases of lassa fever, it significantly reduces mortality when administered before day 7 of illness to persons at high risk. in rod ...	1989	2546248
epidemiology of hemorrhagic fever viruses.	twelve distinct viruses associated with hemorrhagic fever in humans are classified among four families: arenaviridae, which includes lassa, junin, and machupo viruses; bunyaviridae, which includes rift valley fever, crimean-congo hemorrhagic fever, and hantaan viruses; filoviridae, which includes marburg and ebola viruses; and flaviviridae, which includes yellow fever, dengue, kyasanur forest disease, and omsk viruses. most hemorrhagic fever viruses are zoonoses, with the possible exception of t ...	1989	2546247
the in vivo antiviral effect of cl246,738 is mediated by the independent induction of interferon-alpha and interferon-beta.	an interferon (ifn) inducer and immunomodulator, cl246,738 [3,6-bis(2-piperidinoethoxy)acridine trihydrochloride], protected mice from lethal infection with semliki forest (sfv) and banzi (bzv) viruses. a single oral dose of cl246,738 (5-150 mg/kg) administered 24 h before intraperitoneal challenge with sfv or bzv fully protected mice from lethal infection. dose-dependent levels of circulating ifn peaked at 24 h in the serum and peritoneal fluid of cl246,738-treated mice. the circulating ifn of ...	1989	2545791
[a survey of antibodies to arboviruses in residents in south-western part of yunnan province].	in order to provide serological evidence for arbovirus infection in yunnan province, 760 samples of human sera collected from nine counties in south-western part of yunnan province were examined for hi antibodies to 11 arboviral antigens. the viruses used in this experiment included 3 alphaviruses (may, vee and chik) and 8 flaviviruses (je, mve, kun, den3, den4, kfd, lgt and pow). 275 samples were found positive for hi antibodies to alphaviruses (36.2%) and 189 of them (68.7%) reacted with may v ...	1989	2544277
n-terminal domains of putative helicases of flavi- and pestiviruses may be serine proteases.	recently we tentatively identified, by sequence comparison, central domains of the ns3 proteins of flaviviruses and the respective portion of the pestivirus polyprotein as rna helicases (a.e.g. et al., submitted). alignment of the n-proximal domains of the same proteins revealed conservation of short sequence stretches resembling those around the catalytic ser, his and asp residues of chymotrypsin-like proteases. a statistically significant similarity has been detected between the sequences of t ...	1989	2543956
antigenic relationships between flaviviruses as determined by cross-neutralization tests with polyclonal antisera.	the recently established virus family flaviviridae contains at least 68 recognized members. sixty-six of these viruses were tested by cross-neutralization in cell cultures. flaviviruses were separated into eight complexes [tick-borne encephalitis (12 viruses), rio bravo (six), japanese encephalitis (10), tyuleniy (three), ntaya (five), uganda s (four), dengue (four) and modoc (five)] containing 49 viruses; 17 other viruses were not sufficiently related to warrant inclusion in any of these comple ...	1989	2543738
flaviviruses can mediate fusion from without in aedes albopictus mosquito cell cultures.	flavivirus-induced polykaryocytes were detected in monolayers of aedes albopictus (clone c6/36) mosquito cells as early as 20 min after adsorbing virus to these cells. a high multiplicity of infection with dengue (den)-1, 2, 3, 4, japanese encephalitis, and yellow fever viruses was required to demonstrate fusion from without (ffwo) with these flaviviruses. optimal conditions for ffwo included exposure of adsorbed virus to ph 6.0 and an incubation temperature of 39 degrees c. den-2 monoclonal ant ...	1989	2543161
the prevalence of antibodies against viruses causing kumlinge and pogosta diseases on the islands of iniö on the southwest coast of finland.	the prevalence of antibodies against viruses causing kumlinge (tick-borne encephalitis) and pogosta disease in the population of iniö, a small island community in southwest finland was measured. antibodies against kumlinge disease were found in 28% of the population, and increased from 10% in the 0-19 year age group to 42% in the 60-79 year age group. the prevalence varied markedly between different islands, being highest in the outer, bushy islands. antibodies against pogosta disease were detec ...	1989	2543059
positive identification of ns4a, the last of the hypothetical nonstructural proteins of flaviviruses.	a radiolabeled protein migrating in sds-polyacrylamide gels near the core protein c of kunjin virus-infected cells was isolated and subjected to n-terminal amino acid sequencing. comparisons with the translation sequence deduced from the known nucleotide sequence identified a hydrophobic protein of 149 amino acids located in the polyprotein sequence between ns3 and ns4b, thus establishing its identity as ns4a with a calculated mr 16,100. the cleavage sites identified at the n- and c-termini are ...	1989	2541547
[results of infecting experimental animals and monkeys with karshi virus].	the paper presents the results of a comparative experimental study of pathoginicity of the karshi virus (flaviviridae) isolated from ornithodoros papillipes ticks collected in uzbekistan, for white mice, syrian hamsters and green monkeys using various administration routes. localization and types of lesions (brain, lungs, liver, spleen, kidneys) as well as the presence of viruses in blood and body organs are described basing on histological and virusological studies. specific antibodies are foun ...	1989	2540406
isolation of murray valley encephalitis and ross river viruses from aedes normanensis (diptera: culicidae) in western australia.	of eight viruses isolated from 28,909 female (643 pools) aedes normanensis collected from the north of western australia, two were identified as murray valley encephalitis virus and six as ross river virus. the two isolates of murray valley encephalitis virus represent the first confirmed isolations of this virus from an aedes species. the possible implications of these findings with regard to virus survival mechanisms during the dry season are discussed.	1989	2540334
two-dimensional gel electrophoresis of rnase t1 resistant oligonucleotides of flavivirus rna using ultrathin gels.	a convenient method employing a commercially available apparatus for two-dimensional gel electrophoresis of rnase t1 resistant oligonucleotides using ultrathin gels has been developed. the methodology overcomes problems commonly associated with the establishment of good, bubble-free, fusion of the first and second dimension gels. the use of ultrathin gels results in autoradiograms with well resolved oligonucleotide spots.	1989	2536383
transcription of infectious yellow fever rna from full-length cdna templates produced by in vitro ligation.	yellow fever (yf) virus is the prototype member of the flavivirus family, a diverse group of human and animal pathogens. a live-attenuated strain of yf virus, called 17d, has been used successfully for human vaccination for more than 50 years. in this report we describe the construction of full-length yf 17d cdna templates that can be transcribed in vitro to yield infectious yf virus rna. because of the instability of full-length yf cdna clones and their toxic effects on escherichia coli, we dev ...	1989	2487295
complement fixing antibodies against arboviruses in horses at lagos, nigeria.	sixty-two sera horse collected from two stables at lagos, nigeria, were tested for complement fixing antibody to 8 arbovirus antigens; chikungunya, igbo-ora, yellow fever, wesselsbron, west nile, potiskum, uganda s and rift valley fever. ten per cent of the horse sera examined contained cf antibody to one or more of the test antigens and indicated considerable arbovirus activity in the two stables. reactions with flavivirus antigens were most common and the highest antibody titres were obtained ...	1989	2485538
epitope analysis of strains of japanese encephalitis virus by monoclonal antibodies.	twenty one strains of japanese encephalitis (je) virus, including 16 from india, were compared antigenically on the basis of their reactivity in immunofluorescence (if), haemagglutination inhibition (hi), elisa with captured antigen (eca), and neutralization (n) tests with je monoclonal antibodies (mabs). these mabs represented three domains of distinct epitopes on the envelope protein, designated as hs-1 to 4 (je specific in hi), hx-1 to 5 (flavivirus cross reactive in hi) and nhs-1 to 2 (non-h ...	1989	2482831
delaying virus maturation for a higher yield of cell associated virus antigens.	negligible amounts of virus were released when infected cells were maintained in low ionic strength medium. the cells accumulated a high titre of virus and its specific antigenic proteins, detected by complement-fixation test. the procedure has potential for production of virus subunit vaccines.	1989	2481802
[antigen signature analysis of dengue-2 viruses strains in hainan china].	in this paper, we try to define the extent of antigenic variation between dengue-2 viruses from hainan province, which had been isolated over a period of 3 years (1985-1987). the dengue-2 viruses were compared with the prototype new guinea b strain and were subjected to antigen signature analysis. eight strains of dengue-2 virus were analyzed by three monoclonal antibodies: flavivirus group, subcomplex dengue-2 type-specific reactive epitopes, over a range of antigen concentration. five out of e ...	1989	2479176
identification of continuous epitopes of the envelope glycoprotein of dengue type 2 virus.	we reacted 490 hexapeptides homologous to the amino acid sequence of the dengue 2 (den-2) virus envelope glycoprotein with antisera from 7 patients with primary den-2 virus infections to identify the continuous epitopes recognized by human igg. there were 124 peptides in 25 clusters (domains) that bound 2 or more antisera. twenty-two peptides in 7 domains bound all 7 convalescent den-2 virus antisera tested, and thus appeared to represent immunodominant epitopes. the evidence that these domains ...	1989	2472749
synthetic peptides derived from the deduced amino acid sequence of the e-glycoprotein of murray valley encephalitis virus elicit antiviral antibody.	we used computer analysis to study hydrophilicity, homology, surface accessibility, molecular flexibility, and secondary structure of the deduced amino acid sequence of the flavivirus envelope (e)-glycoprotein. using the results, we modified the e-glycoprotein antigenic structure proposed by nowak and wengler (1987, virology, 156, 127-137). our model predicts considerable overlaps in the previously defined domains. we have prepared 11 synthetic peptides from the deduced amino acid sequence of th ...	1989	2472704
an analysis of the antibody response against west nile virus e protein purified by sds-page indicates that this protein does not contain sequential epitopes for efficient induction of neutralizing antibodies.	the large envelope (e) protein of flaviruses is the viral surface protein that contains neutralizing epitopes. we have analysed the e protein of the west nile (wn) flavivirus for neutralizing epitopes generated from linear segments of the protein; if effective, these might allow the synthesis of peptides suitable for vaccination. for this study we used the e protein and defined fragments thereof as antigens in rabbits. the sera thus obtained, containing antibodies to e protein as shown by wester ...	1989	2471801
flavivirus infection up-regulates the expression of class i and class ii major histocompatibility antigens on and enhances t cell recognition of astrocytes in vitro.	west nile virus (wnv) infection of astrocytes can up-regulate their expression of both class i and class ii major histocompatibility complex (mhc) antigens as determined by flow cytometry with monoclonal antibodies specific for class i and class ii mhc antigens. the up-regulation of class i mhc antigen expression could be partly caused by interferon secreted after wnv infection because the synthetic interferon inducer polyinosinic-polycytidylic acid (poly i:c) has similar effects. in contrast th ...	1989	2463998
antigenic structure of the flavivirus envelope protein e at the molecular level, using tick-borne encephalitis virus as a model.	a model of the tick-borne encephalitis virus envelope protein e is presented that contains information on the structural organization of this flavivirus protein and correlates epitopes and antigenic domains to defined sequence elements. it thus reveals details of the structural and functional characteristics of the corresponding protein domains. the localization of three antigenic domains (composed of 16 distinct epitopes) within the primary structure was performed by (i) amino-terminal sequenci ...	1989	2463377
epitope mapping of japanese encephalitis virus envelope protein using monoclonal antibodies against an indian strain.	a panel of monoclonal antibodies (mabs) raised against an indian strain of japanese encephalitis (je) virus was used to map topographically the epitopes on the envelope protein. two separate clusters of epitopes were revealed. on the basis of reactivity in haemagglutination inhibition (hi), neutralization (nt), passive protection and antibody-dependent plaque enhancement (adpe) assays with the mabs, five functional domains (a, b, c, d and e) were delineated. the flavivirus cross-reactive domain ...	1988	2460583
protection of mice against japanese encephalitis virus by passive administration with monoclonal antibodies.	we have identified and characterized nine antigenic epitopes on the e envelope of japanese encephalitis virus (jev) by using mab. passive administration of most of the anti-jev mab protected mice from i.v. challenge with 1.5 x 10(3) plaque-forming units of jev, jagar-01 strain. some mab, which possess high neutralization activity in vitro, showed high protection, and jev-specific n mab 503 was found the most protective. even an injection of 2.5 micrograms/mouse of mab 503 protected all mice from ...	1988	2460542
antigenic structure of the murray valley encephalitis virus e glycoprotein.	to complement our battery of st louis encephalitis (sle) virus monoclonal antibodies (mabs), we isolated and characterized mabs reactive with another member of the sle virus serocomplex, murray valley encephalitis (mve) virus. from 40 fusion products, we isolated 10 stable hybridomas. the combination of sle and mve virus mabs defined eight epitopes on the mve envelope (e) glycoprotein. six of these epitopes (e-1a, e-1c, e-1d, e-3, e-4a, e-4b) were identical to those previously demonstrated on sl ...	1988	2453607
type-specific monoclonal antibodies produced to proteins of murray valley encephalitis virus.	two monoclonal antibodies have been produced to the flavivirus, murray valley encephalitis (mve). immunofluorescent antibody and elisa tests revealed that one antibody was specific for mve while the other cross-reacted weakly with alfuy and kunjin viruses. these antibodies have neither haemagglutination inhibition nor neutralising activity. one of the monoclonal antibodies reacted with the envelope glycoprotein (e) and a 45,000 mw protein, while the other reacted with a protein of 23,000 daltons ...	1988	2453454
from the world health organization. current approaches to the development of dengue vaccines and related aspects of the molecular biology of flaviviruses.		1988	2452218
location of a neutralization determinant in the e protein of yellow fever virus (17d vaccine strain).	the location of a major antigenic determinant involved in the neutralization of a flavivirus, yellow fever virus (yf), has been defined in terms of its position in the amino acid sequence of the e protein. neutralization escape variants of the 17d vaccine strain of yf were selected with two neutralizing monoclonal antibodies. nucleotide sequencing of the envelope protein genes (e and m) of the variants showed that in each variant there was a single nucleotide change in the e gene leading to a no ...	1987	2446422
detection of flavivirus antibodies in human serum by epitope-blocking immunoassay.	human flavivirus group-reactive, dengue complex-reactive, and encephalitis virus complex-reactive antibodies were detected using epitope-blocking immunoassays in which the binding of selected mouse monoclonal antibodies to flavivirus antigens was blocked by human serum. when late (greater than 6 months after illness) convalescent sera were tested, the epitope-blocking immunoassays were superior to the hemagglutination inhibition test and comparable to the plaque reduction neutralization for iden ...	1987	2445910
antigenicity of japanese encephalitis virus envelope glycoprotein v3 (e) and its cyanogen bromide cleaved fragments examined by monoclonal antibodies and western blotting.	purified japanese encephalitis (je) virus was solubilized under reducing condition by using 2-merceptoethanol (2 me) or nonreducing condition without 2 me and its structural proteins were separated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (sds-page), followed by the western blotting using polyclonal and monoclonal antibodies against je. the mobilities and reactivities against polyclonal antiserum of v3 (e) and v2 (c) were reduced when virion was disrupted u ...	1987	2441683
studies on the glycosylation of flavivirus e proteins and the role of carbohydrate in antigenic structure.	the glycosylation pattern of several flavivirus e proteins as well as the role of carbohydrate in biological functions and the antigenic structure of tick-borne encephalitis (tbe) virus were investigated by the use of specific endoglycosidases. endoglycosidase f digestion revealed the presence of a single asparagine-linked oligosaccharide side chain in tbe virus (western and far eastern subtype), louping iii virus, murray valley encephalitis virus, and rocio virus. consistent with published sequ ...	1987	2441520
antigenic comparison of envelope protein e between japanese encephalitis virus and some other flaviviruses using monoclonal antibodies.	the antigenic relationships between japanese encephalitis (je) virus and several other flaviviruses have been investigated using anti-je virus monoclonal antibodies (mabs). seventeen mabs directed against envelope protein e of je virus were characterized and divided into eight mab groups based on reactivity patterns in haemagglutination inhibition test, neutralization (n) test, elisa and competitive binding assay with je virus. the results suggest the existence of at least eight epitopes on the ...	1986	2432163
geographic classification of dengue-2 virus strains by antigen signature analysis.	dengue-2 virus strains from different locations were compared by t1-rnase-resistant oligonucleotide fingerprinting and antigen signature analysis. the latter technique involved construction of radioimmunoassays using monoclonal antibodies that recognize nine distinct dengue-2 type-specific and flavivirus cross-reactive epitopes over a range of antigen concentrations. a statistical method was used to align unknown dengue antigen concentrations in different strain preparations, allowing comparison ...	1986	2429440
epitope mapping of flavivirus glycoproteins.		1986	2428213
the cap structure of simian hemorrhagic fever virion rna.	the molecular weight of simian hemorrhagic fever virus rna is 4.19 +/- 0.53 x 10(6) as determined by electron microscopy. its base composition is 19.5 +/- 0.3 a, 33.3 +/- 0.3 u, 26.7 +/- 0.9 g, and 19.7 +/- 0.3 c per 100 nucleotides. the rna of simian hemorrhagic fever virus contains a single type i cap per molecule, in the form m7g(5')ppp(5')am.	1986	2421482
multisite monoclonal immunoassay for dengue viruses: detection of viraemic human sera and interference by heterologous antibody.	a monoclonal radioimmunoassay (ria) was developed for detection of dengue virus in infected cell culture fluids and blood samples from dengue patients. antibodies used to construct the ria were selected on the basis of high binding avidity, the demonstration of synergism in competitive binding assays and empirical trials with different antibody combinations. optimal binding of all four dengue virus serotypes was achieved by use of a flavivirus group-reactive and a dengue virus complex-reactive a ...	1986	2420923
studies on the antigenic structure of japanese encephalitis virus using monoclonal antibodies.	the antigenic relationships among 11 strains of japanese encephalitis (je) virus were analyzed by using monoclonal antibodies (narma) against the nakayama-rfvl strain in hemagglutination-inhibition (hi) and neutralization (nt) tests. of the 14 je virus-specific hi antibodies, all except narma 5 showed nt reactivity with the homologous strain. the hi and nt titers of these antibodies were not parallel. the 14 antibodies included the following characteristic antibodies: narma 3 is a species-specif ...	1985	2419739
temperature-sensitive mutants of japanese encephalitis virus.	ten stable temperature-sensitive mutants of japanese encephalitis virus were isolated after mutagenesis by growth of cloned wild-type virus in the presence of the nucleic acid precursor analogs 5-fluorouracil and 5-azacytidine. mutants were selected which grew at least 100-fold better at 33 degrees c than at 41 degrees c. the 5-fluorouracil was found to be more effective at inducing temperature-sensitive mutations than was 5-azacytidine. analysis of the virus-specific rna and proteins synthesize ...	1985	2410633
examination of the immunological relationships between flaviviruses using yellow fever virus monoclonal antibodies.	monoclonal antibodies prepared against vaccine strains of yellow fever (yf) virus were initially characterized by fluorescence microscopy of vero cells infected with yf virus strain 17d. when similarly tested against representatives of all flavivirus subgroups, the antibodies produced a wide spectrum of reactions ranging from the monospecific to the broadly cross-reactive; at least five antigenic domains in the yf virus envelope glycoprotein were identified. monoclonal antibodies differentiated ...	1985	2410549
a single amino acid substitution in envelope protein e of tick-borne encephalitis virus leads to attenuation in the mouse model.	we have determined the virulence characteristics of seven monoclonal antibody escape mutants of tick-borne encephalitis virus in the mouse model. one of the mutants with an amino acid substitution from tyrosine to histidine at residue 384 revealed strongly reduced pathogenicity after peripheral inoculation of adult mice but retained its capacity to replicate in the mice and to induce a high-titered antibody response. infection with the attenuated mutant resulted in resistance to challenge with v ...	1990	2398538
preparation of an attenuated dengue 4 (341750 carib) virus vaccine. ii. safety and immunogenicity in humans.	to determine safety and immunogenicity, a single 0.5 ml dose of a monovalent live-attenuated dengue (den) 4 (341750 carib) vaccine was given sc to 3 groups of flavivirus nonimmune volunteers in increasing concentrations. two recipients received 10(3) plaque forming units (pfu)/dose (1:100 dilution of stock vaccine). one remained asymptomatic, but became viremic between days 12 and 15, experienced a mild elevation of temperature (37.4 degrees c), and developed den-4 specific antibody. neither rec ...	1990	2389825
antibodies to dengue 2 virus e-glycoprotein synthetic peptides identify antigenic conformation.	eighteen synthetic peptides have now been prepared from dengue (den) 2 virus, representing 80% of the extra-membranal domain of the den envelope (e)-glycoprotein. these peptides were selected based upon our previous results with murray valley encephalitis (mve) virus, computer analysis of the den virus sequence, and the predicted e-glycoprotein secondary structure. six of these peptides were "structural" peptides derived from either nonlinear amino acid sequences or predicted disulfide bridge-st ...	1990	2371772
prophylactic ribavirin treatment of dengue type 1 infection in rhesus monkeys.	the prophylactic efficacy of the broad-spectrum antiviral nucleoside analog ribavirin against flavivirus infection in non-human primates was investigated in a blinded, placebo-controlled study of rhesus monkeys infected with dengue virus. both placebo- and ribavirin-treated monkeys developed viremia, as measured by direct plaque assay on aedes albopictus c6/36 cells. peak viremia occurred between days 3 and 9 after infection. no significant differences in time of onset, duration, or level of vir ...	1990	2353804
production of yellow fever virus proteins in infected cells: identification of discrete polyprotein species and analysis of cleavage kinetics using region-specific polyclonal antisera.	flavivirus proteins are produced by translation of a single long open reading frame and a complex series of cotranslational and post-translational proteolytic cleavages. to study these processing events in yellow fever virus (yf)-infected cells, polyclonal antisera recognizing c, prm, e, ns1, ns2b, ns3, ns4b, and ns5 were generated using peptide and fusion protein immunogens. evidence suggests that production of the structural protein precursors involves rapid cotranslational processing consiste ...	1990	2353452
measurement of antibody-dependent infection enhancement of four dengue virus serotypes by monoclonal and polyclonal antibodies.	although its underlying mechanisms are poorly understood, data comparing each of the four dengue virus serotypes suggest that in vitro antibody-dependent infection enhancement is a reproducible and measurable phenomenon related to other serological measures of antibody-virus binding. information characterizing infection enhancement may provide clues to disease pathogenesis for dengue and other viruses that exhibit antibody-enhanced infection. we propose criteria for the detection and quantificat ...	1990	2273390
expression of the structural proteins of dengue 2 virus and yellow fever virus by recombinant vaccinia viruses.	vaccinia virus recombinants were constructed which contained cdna sequences encoding the structural region of dengue 2 virus (pr159/s1 strain) or yellow fever virus (17d strain). the flavivirus cdna sequences were expressed under the control of the vaccinia 7.5k early/late promotor. cultured cells infected with these recombinants expressed immunologically reactive flavivirus structural proteins, precursor prm and e. these proteins appeared to be cleaved and glycosylated properly since they comig ...	1990	2260923
yellow fever haemagglutination-inhibiting, neutralising and igm antibodies in vaccinated and unvaccinated residents of ibadan, nigeria.	a survey for yellow fever virus haemagglutination inhibiting (hi) and neutralising (n) and igm antibodies was carried out in unvaccinated people in ibadan and in those immunised with the yellow fever 17-d vaccine. a total of 207 people were tested for hi antibody to yellow fever and two other flaviviruses namely: wesselsbron and uganda s. viruses. prevalence of hi antibody to each flavivirus antigen was as follows: yellow fever 26%, wesselsbron 18% and uganda s 33%. of the 207 people, 37 (18%) h ...	1990	2208973
vertical maintenance of dengue-1 virus in sequential generations of aedes albopictus.	vertical transmission of dengue-1 virus was demonstrated over 3 consecutive generations of aedes albopictus by tracing descendants of individual, vertically infected females. this study is the first to examine efficiency of vertical transmission of a flavivirus by vertically infected mosquitoes. vertically infected ae. albopictus females were more efficient vertical transmitters than females infected by inoculation (i.e., horizontally). three of 4 vertically infected females examined transmitted ...	1990	2196337
[hepatitis c virus. identification and structural organization].		1990	2177592
[non-a, non-b hepatitis: hepatitis c].	non-a, non-b hepatitis (nanb), whether following the transfusion of blood products or occurring sporadically without percutaneous exposure, is complicated in approximately 50% of cases by the development of chronic hepatitis. emerging as a consistent observation is the insidious progression of such cases of chronic nanb hepatitis to cirrhosis. among patients with chronic nanb hepatitis followed for up to 10 years, cirrhosis is demonstrable in 20%. in may, 1988, the identification of the agent of ...	1990	2177314
primer extension dideoxy chain termination nucleotide sequencing of partially purified rna virus genomes: a technique for investigating low titre viruses with extensive genome secondary structure.	a modified version of the primer extension dideoxy chain termination nucleotide sequencing technique (sanger et al., 1977) is described. this method has advantages over existing molecular cloning and primer extension techniques in that it allows the genome of rna viruses to be directly sequenced from partially purified rna preparations. thus, viruses growing at unacceptably low titres in tissue culture can now be partially purified from infected mouse brain and sequenced. the technique also inco ...	1990	2176663
outbreak of encephalitis in bellary district of karnataka & adjoining areas of andhra pradesh.	an outbreak of encephalitis in bellary district of karnataka state and adjoining areas of andhra pradesh which occurred during october 1986 to january, 1987, has been investigated. out of the 219 patients reported, 110 were from bellary district and the remaining 109 were from anantapur and kurnool districts of andhra pradesh; 131 (59.8%) were males and 88 (40.2%) females, while 192 (87.7%) patients were aged 10 yr and below. sixty one patients died giving a case fatality rate of 27.9 per cent. ...	1990	2176645
flavivirus genome organization, expression, and replication.		1990	2174669
[mechanism of flavivirus rna replication].		1990	2173731
successful competition in translation by the flavivirus kunjin with poliovirus during co-infections in vero cells.	infection with poliovirus effectively inhibited the translation of vero cell messengers (carrying type 1 or type 2 caps at the 5' end) and of influenza virus messengers (type 1 caps) in co-infections. in contrast, kunjin virus rna (type 1 caps) and semliki forest virus rna (a togavirus, with type 0 caps) continued to be translated in the presence of co-infecting poliovirus. translation of kunjin virus rna was also unaffected during co-infections with either influenza virus or semliki forest viru ...	1990	2171465
low ph-induced cell fusion in flavivirus-infected aedes albopictus cell cultures.	cell-to-cell fusion of aedes albopictus (mosquito) cells infected with dengue and st louis encephalitis (sle) flaviviruses was induced by exposure to low ph. the parameters of this low ph-induced fusion were examined. syncytium formation was maximal in cultures 36 to 48 h post-infection and occurred when cultures were maintained at the acid ph for 15 min at 35 degrees c. the optimal ph range for fusion was 5.0 to 6.5 for dengue virus-infected cells and 5.0 to 5.5 for sle virus-infected cells. sy ...	1990	2167941
diel changes in adult mosquito microhabitat temperatures and their relationship to the extrinsic incubation of arboviruses in mosquitoes in kern county, california.	microhabitat temperatures experienced by nocturnally active culex tarsalis coquillett mosquitoes were measured in the southern san joaquin valley of california. temperatures of the diurnal resting shelter and nocturnal activity air space were measured by digital recorder at three cx. tarsalis habitats in kern county. temperatures measured by digital recorders agreed well with temperatures recorded concurrently at nearby california irrigation management and inspection system weather stations. mon ...	1990	2167374
synthesis and broad-spectrum antiviral activity of 7,8-dihydro-7-methyl-8-thioxoguanosine.	2,6,8-trichloro-7-methylpurine (3) was converted to 2-chloro-8,9-dihydro-7-methyl-8-thioxopurin-6(1h)-one (5) by utilizing the difference in reactivity of the 2-, 6-, and 8-positions in the trichloropurine ring system to nucleophilic displacement. compound 5 was subsequently glycosylated with 1-o-acetyl-2,3,5-tri-o-benzoyl-d-ribofuranose according to the vorbrüggen procedure to yield 2-chloro-8,9-dihydro-7-methyl-9-(2,3,5-tri-o-benzoyl-beta-d-ribofuranosy l)-8- thioxopurin-6(1h)-one (6). removal ...	1990	2165160
host cell selection of murray valley encephalitis virus variants altered at an rgd sequence in the envelope protein and in mouse virulence.	we have passaged the prototype strain of murray valley encephalitis virus in sw13 (human) cells, sequenced the e and m genes, and examined the virulence of the passaged virus for 21-day-old mice following intracranial and intraperitoneal inoculation. six independent passage series were carried out: four in the presence of mouse hyperimmune ascitic fluid and two without antibody. changes were observed in the e protein deduced amino acid sequence for each of the six 10th passage stocks sequenced. ...	1990	2161151
flaviviruses and bone marrow failure.		1990	2160551