nucleotide sequence of the 5'-terminal untranslated part of the genome of the flavivirus west nile virus.we have determined the nucleotide sequence of the 5'-terminal untranslated region of the 42 s genome rna of the flavivirus west nile virus by primer extension. these analyses make our primary structure determination of this genome, which comprises a total number of 10,960 nucleotides, complete. some implications of our data concerning the structure of flavivirus-specific nucleic acids and the initiation of translation of wn virus-specific rna are discussed.19873813889
comparison of dengue virus plaque reduction neutralization by macro and "semi-micro' methods in llc-mk2 cells.a simplified "semi-micro' plaque reduction neutralization test (prnt) for dengue antibody in llc-mk2 cells in disposable tissue culture plates is described. the assay compares favorably with the standard prnt in glass prescription bottles, with relative sensitivity and specificity both 100% at a 1:40 screening dilution by 70% plaque reduction criteria. the assay is easy to perform, economical of time, expense, and storage space, and is suitable for study of sera available in small volumes, such ...19853831719
serotyping of dengue viruses by an enzyme-linked immunosorbent assay.we have developed a sandwich enzyme-linked immunosorbent assay for serotyping dengue viruses. in this assay, we used antibody from dengue hemorrhagic fever patients for detection of flavivirus common antigens to confirm virus isolation in c6/36 cells and that from hyperimmune mouse ascitic fluids for serotyping. the anti-dengue antibody was immobilized on microplate wells for capturing of dengue antigens, which were then sandwiched with the same biotinylated antibody. then the biotin in the soli ...19853834210
sequence analysis of the membrane protein v3 of the flavivirus west nile virus and of its gene.flaviviruses contain a large membrane-associated protein v3, having a mol mass of about 50 kda which is responsible for hemagglutination. we have isolated the v3 protein from the west nile (wn) flavivirus and determined its amino-terminal amino acid sequence and amino acid sequences of fragments derived from this protein. we have also transcribed parts of the wn virus genome rna into cdna and cloned and sequenced this cdna. the results of these analyses have allowed us to identify the region of ...19853855247
lethal 17d yellow fever encephalitis in mice. i. passive protection by monoclonal antibodies to the envelope proteins of 17d yellow fever and dengue 2 viruses.monoclonal antibodies to the envelope proteins (e) of the 17d vaccine strain of yellow fever virus (17d yf) and to dengue 2 virus were examined for their ability to confer passive protection against lethal 17d yf encephalitis in mice. all 13 igg anti-17d yf antibodies, regardless of neutralizing capacity, conferred solid protection when given in a relatively high dose prior to intracerebral inoculation of virus. three antibodies with high in vitro neutralizing titres were all protective at a low ...19863944585
[dengue in burkina faso (ex-upper volta): seasonal epidemics in the urban area of ouagadougou].during the rainy season of 1982 30 patients (29 european and 1 voltaic) presented with an intense dengue-like syndrome in ouagadougou city. 73.3% of these cases possessed anti-flavivirus fluorescent antibodies while 30%, were positive for specific anti-dengue igm antibodies. vero type e 6 cell cultures were used to isolate six strains of dengue 2 virus; monoclonal antibodies were used for viral identification. these strains constitute the first isolates of human dengue virus in upper volta. auth ...19853886182
use of the biotin-streptavidin interaction to improve flavivirus detection by immunofluorescence and elisa tests.the specificity and sensitivity of immunofluorescence microscopy and elisa tests were compared both with and without the use of biotinylated anti-species antibody and streptavidin, conjugated with either fluorescein isothiocyanate or horse radish peroxidase. in the biotin-streptavidin system monoclonal and polyclonal antibodies against yellow fever virus had titres between ten- and fifty-fold higher and background readings, particularly in elisa tests, were noticeably reduced. plaque variants of ...19853891767
ph-dependent fusion between the flavivirus west nile and liposomal model membranes.fusion between purified [3h]uridine-labelled west nile virus (wnv) particles and liposomes containing rnase, was assayed by degradation of the viral rna to trichloroacetic acid-soluble material. fusion of virus with liposomes containing phosphatidylcholine, phosphatidylethanolamine, sphingomyelin and cholesterol (at a molar ratio of 1:1:1:1.5) was found to be dependent on ph with maximum fusion occurring at ph 6.7 and below. at ph 6.6 fusion was rapid and was essentially complete within 2 min at ...19863944582
nucleotide sequence of yellow fever virus: implications for flavivirus gene expression and evolution.the sequence of the entire rna genome of the type flavivirus, yellow fever virus, has been obtained. inspection of this sequence reveals a single long open reading frame of 10,233 nucleotides, which could encode a polypeptide of 3411 amino acids. the structural proteins are found within the amino-terminal 780 residues of this polyprotein; the remainder of the open reading frame consists of nonstructural viral polypeptides. this genome organization implies that mature viral proteins are produced ...19854023707
identification of dengue type 2 virus-specific high molecular weight proteins in virus-infected bhk cells.evidence is presented for the production in dengue type 2 virus (den-2)-infected bhk cells of large virus-specific proteins with molecular weights up to 250 000. these proteins were most prominent in lysates of cells which had been labelled with [35s]methionine for 7 to 15 min. during pulse-chase experiments, these high mol. wt. proteins appeared to be converted into smaller, more stable, proteins with mol. wt. between 10 000 and 98 000. finally, inhibition of proteolysis prevented the chasing o ...19854067585
protection against 17d yellow fever encephalitis in mice by passive transfer of monoclonal antibodies to the nonstructural glycoprotein gp48 and by active immunization with gp48.the protective capacity of antiviral antibodies has generally been considered to depend on their interactions with structural components of the virion. here we report protection against lethal 17d yellow fever virus (yf) encephalitis of mice by passive administration of nonneutralizing monoclonal antibodies to a 17d yf-specified nonstructural glycoprotein, gp48, and by active immunization with purified gp48. among five anti-gp48 monoclonal antibodies tested, two with high titer complement-fixing ...19854031501
flavivirus infection enhancement in macrophages: an electron microscopic study of viral cellular entry.the mode of entry of west nile virus (wnv) into the macrophage-like cell line p388d1 was investigated at the electron microscopical level using synchronized infections. the presence of the antiviral monoclonal antibody f6/16a at a concentration that enhanced viral attachment to p388d1 cells ninefold made no difference to the entry pathway of wnv. in both the absence and presence of f6/16a the initial uptake of single viral particles was mediated by coated pits, and started within 30 s of warming ...19854031825
the association of enhancing antibodies with seroconversion in humans receiving a dengue-2 live-virus vaccine.a group of human subjects, some with yellow fever (yf) antibodies, volunteered for testing of a live-attenuated dengue-2 (den-2) vaccine. serum samples taken before den-2 vaccination were tested for their ability to enhance infection of human monocytes by den-2 virus. a significantly greater proportion of enhancing antibodies (eab) were found in yf-immune (yfi) individuals (50%) as compared to those with no evidence of flavivirus infection (9.5%). geometric mean titers of neutralizing and hemagg ...19854067313
[arbovirus serological survey among marine and non-marine birds of brittany].sera from 215 seabirds (mainly gulls) and 74 landbirds (mainly starlings) from brittany were studied by hemagglutination inhibition and complement fixation tests for antibody against 9 arboviruses among them 8 were previously isolated from ticks associated with seabirds. among seabirds, 145 or 65% were found positive for flaviviruses and nairoviruses of the hughes serogroup. unexpected frequency of hi positive reactions for tyuleniy virus indicate the possible circulation of this virus among sea ...19854085099
the isolation of ilhéus virus from man in panamá. 19674378148
flavivirus infection enhancement in macrophages: radioactive and biological studies on the effect of antibody on viral fate.35s-labelled west nile virus was used in radioactive binding, internalization and degradation studies in the macrophage cell line p388d1 in the absence or presence of various concentrations of antiviral antibody. proteases were used to help distinguish between intracellular and extracellular (bound) virus. it was found that the enhancement in viral infectivity that occurs in the presence of subneutralizing concentrations of antiviral antibody was caused by (i) increased binding of virus to the c ...19846086817
evidence for flavivirus(es) outside of the distribution area for ixodes ricinus in norway.small rodent (vole) sera were collected from three different locations in norway. one of these was within the distribution area for ixodes ricinus, and a tick-borne encephalitis (tbe) virus strain had been isolated from ticks collected there (traavik & mehl, 1977). the two other locations were outside the i. ricinus area, one in southern norway, the other at nearly 70 degrees n. the sera were tested for tbe antibodies by hemagglutination inhibition (hi), hemolysis-in-gel (hig) and complement fix ...19846086747
"original antigenic sin" phenomenon in experimental flavivirus infections of guinea pigs: studies by enzyme-linked immunosorbent assay.guinea pigs were sequentially infected with two closely related flavivituses (japanese encephalitis and west nile viruses), and their antibody responses were studied both by enzyme-linked immunosorbent assay (elisa) and hemagglutination-inhibition (hi). the results by elisa always showed "original antigenic sin" responses: antibody activity of sera after the second infection was higher to the first infecting virus than to the second infecting virus. however, the results obtained by hi were varia ...19846088953
acid production by flavivirus-infected vero and cer cell cultures.vero and cer cell cultures infected with flaviviruses produce more acid than non-infected control cultures. acid production is dependent on the presence of glucose. this phenomenon can be utilized for the titration of flaviviruses.19846087235
viral haemorrhagic fevers: properties and prospects for treatment and prevention. 19846091539
[prevalence of antibodies against st. louis encephalitis virus in various marine birds from panama]. 19846093203
a protective mechanism induced by live group b arboviruses against heterologous group b arboviruses independent of serum neutralizing antibodies or interferon. 19674378109
a simplified new method for the identification of arboviruses: virus detection using enzyme immunoassay on cultured cells.a simple new method is reported for the identification of arbovirus isolates and the titration of arboviruses. horseradish peroxidase conjugated staphylococcus aureus protein a was used for the indirect staining of virus antigens grown in an aedes albopictus cell line, c6/36 cells. thirty-five isolates from culex tritaeniorhynchus mosquitoes were examined by this method and 20 of these were identified as japanese encephalitis virus (jev). these results were confirmed by immunofluorescent assay a ...19846094608
[serologic survey on arbovirus infections in patients presenting with uveitis].viruses have been demonstrated or suspected as the causative agents of various types of uveitis. some arboviruses can be responsible for ocular manifestations. in brittany, both serosurveys and virus isolations were positive for arboviruses. these results led us to look for the possible role of arboviruses in the aetiology of uveitis. for this, we performed a serosurvey on 131 patients with uveitis of unknown aetiology. patients were examined in the ophthalmologic department of the brest univers ...19846094643
antigenic analysis of flaviviruses with monoclonal antibodies against negishi virus.twelve monoclonal antibodies against negishi virus were obtained and characterized by hemagglutination inhibition (hi) and neutralization (nt) tests using five flaviviruses isolated in the pan-pacific region. the reaction pattern of the antibodies showed that negishi virus was most closely related to langat virus, followed by 3-arch, je and apoi viruses in that order. hemagglutinating (ha) antigen of the virus had distinct hi relating sites which were negishi virus specific, tick borne encephali ...19846096680
[effectors of in vivo delayed hypersensitivity in experimental flavivirus infections and vaccination against tick-borne encephalitis in mice].the development of experimental infections caused by tick-borne encephalitis (tbe) virus, langat virus and dengue virus type 2 in mice or the immunization of these animals with live yellow fever vaccine (prepared from strain 17d) and inactivated tbe vaccine were accompanied by the formation of delayed hypersensitivity (dh) to viral antigens, determined in vivo. in experimental tbe infection the effectors of dh were identified as t-lymphocytes whose action was specific and followed the rule of h- ...19846098109
purification of the structural and nonstructural proteins of st. louis encephalitis virus.we have developed a procedure for purifying both the structural and nonstructural proteins of flaviviruses from lysates of infected cell cultures. the procedure involves: immunoprecipitation to concentrate viral proteins and eliminate most of the cellular proteins, preparative polyacrylamide gel electrophoresis to separate the viral proteins, and hydroxyapatite chromatography, which eliminates most of the unlabeled cellular protein. this procedure offers an improvement over previous purification ...19846099371
serological evidence of infection with california serogroup viruses (family bunyaviridae) in residents of long hua, suburb of shanghai, people's republic of china.sera from 126 residents of long hua, a suburb of shanghai, in the people's republic of china, were studied. sera were tested for haemagglutination inhibiting antibodies to alphavirus (eastern equine encephalitis, western equine encephalitis), flavivirus (st. louis encephalitis, powassan, dengue) and california serogroup (snowshoe hare) antigens. flavivirus antibodies were found in 14 (11.1%) and california serogroup antibodies in 5 (3.9%) individuals. neutralizing antibodies with highest titres ...19846099922
the vector competence of australian culex annulirostris with murray valley encephalitis and kunjin viruses.australian populations of culex annulirostris skuse from 10 localities, brisbane, townsville, cairns, charleville, kowanyama (queensland), darwin (northern territory), mildura (victoria) and port hedland, karratha and mt. tom price (western australia) showed considerable heterogeneity in response to oral infection with low passage level murray valley encephalitis (mve) and kunjin (kun) viruses. however, there was no consistent pattern of either high or low vector efficiency for populations colle ...19846100042
cross-reactive killer t lymphocytes in a flavivirus infection.splenocytes from mice immunized intravenously with one dose of langat or yellow fever viruses were cytotoxic for target cells infected with virulent tick-borne encephalitis (tbe) virus; cytotoxicity was measured by 51cr release from target l929 cells. no significant lysis of the tbe virus-infected taget cells with splenocytes from sindbis virus-infected mice was noted.19806106380
gene order of translation of the flavivirus kunjin: further evidence of internal initiation in vivo.the rates of inactivation of synthesis of individual virus-specified proteins by ultraviolet radiation provided an estimate of the target sizes of individual viral genes. in a control experiment with semliki forest virus, the genes for the structural proteins mapped in the known sequence 5' c-pe2-e1 3', and in accordance with initiation of translation from a single site on 26-s mrna. under the same conditions, the inactivation of synthesis of seven kunjin virus-specified proteins also followed f ...19846099663
arboviruses of coastal south-eastern australia.during investigations of epidemic polyarthritis at nelson bay, new south wales, 12 strains of ross river virus, the causative agent, were recovered from pools of mosquitoes. in addition, the mosquito pools yielded 9 strains of the flavivirus edge hill, 4 strains of a bunyavirus, gan gan, 1 strain of an orbivirus tilligerry, and 1 strain of an ungrouped probable arbovirus, yacaaba. the latter 3 viruses were found to be antigenically distinct from previously recorded arboviruses. a case of epidemi ...19806108758
emergence of a new arbovirus disease in brazil. iii. isolation of rocio virus from psorophora ferox (humboldt, 1819).a newly described flavivirus was responsible for a large encephalitis epidemic in são paulo state, brazil. the etiologic agent, rocio virus, was isolated from human patients and sentinel mice. the natural history of the virus is unknown although presumed to be arthropod-borne. rocio virus was isolated from a single pool containing 19 psorophora ferox of 47 pools (283 specimens) of this species tested. the positive pool contained 16 deplete, 2 gravid, and 2 engorged mosquitoes. no isolations were ...19816110335
transfer with dialysable transfer factor of t-lymphocyte cytolytic response to tick-bone encephalitis virus antigen in naive mice.transfer factor activity was demonstrated in the dialysable extract from lymphocytes from outbred donor mice, in which immunization with live attenuated langat (e5 "14") virus induced a stage of high resistance against challenge with virulent tick-borne encephalitis virus. administered to naive inbred recipient mice, the extract conveyed in them specific cytolytic activity, exerted by their t lymphocytes, as demonstrated by the 51cr release assay on tick-borne encephalitis virus-infected syngene ...19806111208
the use of toxorhynchites mosquitoes to detect and propagate dengue and other arboviruses.both sexes of toxorhynchites amboinensis, an unusually large, non-blood sucking mosquito, were found to be as susceptible to infection with each of the four types of dengue virus by intrathoracic inoculation as aedes albopictus. tx. amboinensis infected with dengue virus could be identified easily by fluorescent antibody staining of head squashes and had advantages of size, hardiness, and safety (for females) as compared with ae. albopictus. tx. amboinensis also were more susceptible to infectio ...19816111230
experimental transmission of rocio virus by mosquitoes. 19816112884
investigations on the structure and morphogenesis of some arboviruses isolated in the u.s.s.r.the morphology and some stages of morphogenesis in suckling mouse brains of hitherto serologically unclassified viruses kaspiy (leiv-a-63), zavashan (leiv-ap-6158), artashat (leiv-a-2366), and paramushir (leiv-c-2268), isolated in the u.s.s.r., of gm-710 virus isolated in scotland, and of sokuluk (leiv-k-400) virus belonging to the genus flavivirus (family togaviridae) were studied. virion sizes were determined and changes in infected cells described. based on their structure and morphogenesis, ...19816115562
[transovarial transmission of arboviruses by mosquitoes (author's transl)].an important aspect of the epidemiology of arboviruses is the manner in which the viruses are maintained during winter, dry season, or other adverse environmental periods when their arthropod hosts are inactive. one possibility is that the viruses survive in arthropods. in the case of mosquito-borne viruses, it is probable that such viruses could be maintained in this manner only if they were transmitted from one insect generation to the next by transovarial transmission. such transmission was r ...19816116146
[arboviral diseases in south-west pacific islands (author's transl)].islands of the south-west pacific area belong to the melanesian group, excepted niue, tonga, wallis and futuna which are polynesian. through new guinea, there is a geographic relation to the eastern part of australia, rich of 42 arbovirus types. dengue and ross river fever are the most important arboviral diseases in the region; both affect islanders after introduction of virus by travellers to localities where efficient vectors are present. dengue types 1, 2 and 4 were isolated from man and fro ...19816116150
isolation of murray valley encephalitis virus and other arboviruses in the ord river valley 1972-1976.this paper summarizes the isolation of arboviruses from mosquitoes collected in the ord valley between 1972 and 1976. a total of one hundred and ninety five strains of at least fifteen antigenically distinct viruses have been isolated. seven of these isolates appear to be "new' antigenic types, and several are undergoing further testing. these are three new rhabdoviruses (kununurra [or194], a virus provisionally named kimberley [or250] and or189 [provisionally named parry's creek]), three ungrou ...19816117274
use of hyperimmune mouse ascitic fluids for arbovirus differentiation by indirect immunofluorescence and conventional serology.the cross-reactivity of 22 arbovirus species (alphaviruses; tick- and mosquito-borne flaviviruses; and selected bunyaviruses) was tested with monovalent immune mouse ascitic fluids by indirect immunofluorescence (iif) in comparison with classical serological reactions (virus neutralization -- vn; haemagglutination inhibition -- hi; and complement fixation -- cf -- reactions). known relationships within the virus groups studied were confirmed. as to the differentiation limits, the vn test was fol ...19816118048
"x" disease in australia (a historical story of medical detection). 19826129177
occurrence of tick-borne encephalitis and other arboviruses in hungary. 19826129178
early diagnosis of viraemia in some experimental arbovirus infections in mice.viraemia was demonstrated by the indirect haemagglutination (iha) test in newborn white mice infected with dengue type 1 and 2 and japanese encephalitis viruses but not with chikungunya virus. the iha allowed the detection of viraemia in the flavivirus infections before the appearance of clinical symptoms of the disease and was strictly specific.19816118053
replication of dengue, yellow fever, st. louis encephalitis and vesicular stomatitis viruses in a cell line (tra-171) derived from toxorhynchites amboinensis.the replication of seven arboviruses in a cell line (tra-171) derived from a nonhematophagous mosquito was studied. four serotypes of laboratory adapted and three serotypes of unadapted dengue viruses replicated in the tra-171 cell line, inducing syncytia. the sensitivity of tra-171 cells to dengue virus infection was comparable to that of aedes albopictus or a. pseudoscutellaris cells. yellow fever, st. louis encephalitis, and vesicular stomatitis viruses also replicated. all four serotypes of ...19816119288
spondweni virus infection in a foreign resident of upper volta.spondweni virus is a mosquito-borne flavivirus previously reported to cause human disease in southern and west africa. a serologically confirmed case of spondweni virus infection in a u.s. citizen residing in upper volta is reported. symptoms included fever, chills, headache, myalgia, nausea, and rash. a greyish mucoid lining was present on the posterior pharynx. the differential diagnosis included rickettsial infection, leptospirosis, typhoid fever, and numerous viral illnesses including lassa ...19826128599
restricted replication of the e5"14" clone of langat tp21 virus (from the tick-borne encephalitis complex) in cns of subadult mice.subadult icr mice were infected with the low virulent langat virus tp21 e5 strain clone "14" belonging to the tick-borne encephalitis (tbe) complex by subcutaneous (s.c.) and intracerebral (i.c.) routes. from 5 to 6 days post infection (p.i.), no virus was detected in cultured brain fragments of mice, which received 10(6) ic ld50 into interscapular area. acute lethal encephalitis with lesions confined to the vicinity of the inoculation area (parietal cortex, basal ganglia, thalamus) has develope ...19826132543
interferon induction by flavi- and orbiviruses in l-m cell line.interferon (ifn) inducing ability of six flaviviruses was compared with five orbiviruses in mouse fibroblast cells (l-m). orbiviruses were found to induce significantly higher amounts of ifn than flaviviruses.19836133435
in vivo inhibition by intact mouse serum of the activity of the flavivirus-induced t-suppressors of autoreactive the serum of healthy mice a factor was found inhibiting the in vivo effect of t-suppressors of autoreactive t-lymphocytes (tsart1) induced in mice by tick-borne encephalitis (tbe) virus, langat virus, dengue virus type 2 (d2) and attenuated strain 17d of yellow fever virus. activity of the serum factor (s) was demonstrated providing that the tsart1 had h-2 antigens completely or partially identical with the h-2 antigens of serum donors. the activity was not connected with destruction of tsart ...19846147997
[biological studies of st. louis encephalitis virus in majé, bayano]. 19846149603
[comparative analysis of the electrophoretic mobility of the high-molecular virus-specific proteins of flaviviruses].a comparative study of high molecular virus-specific proteins in cells infected with flaviviruses from 5 serological subgroups was carried out. proteins nv5, nv4, and v3 were found to have similar electrophoretic mobility in viruses of the tick-borne encephalitis (tbe) complex with the exception of powassan virus protein. proteins nv5 and nv4 of mosquito-borne flaviviruses differ in electrophoretic mobility both from the corresponding proteins of the tbe complex viruses and from each other. prot ...19846152087
serum factor blocking the activity of virus-induced autoreactive t lymphocytes of mice.normal mouse serum was found to contain a factor blocking in vivo the effect of autoreactive cells accumulating in spleens of mice infected with tick-borne encephalitis (tbe), langat, dengue type 2 (d2), and attenuated yellow fever (17d strain) viruses. the activity of the factor was manifested only, when the autoreactive lymphocytes had h-2 antigens identical with h-2 antigens of the serum donors. the hypothesis is discussed that serum factor protects the host against clones of autoreactive t l ...19836138997
enhancement of dengue virus infection in monocytes by flavivirus antisera.enhanced dengue 2 virus (d2v) infection in suspension cultures of human peripheral blood mononuclear phagocytes (pbl) produced by subneutralizing concentrations of dengue antisera has been described previously. in this study, the enhancement phenomenon was found to be a general property of representative flavivirus antisera. all except one of 24 antisera, which had been raised by 1-3 injections of flaviviruses in rabbits, enhanced the growth of dengue 2 virus in human pbl. flavivirus antisera sh ...19806157332
identification of the antiviral factor in culture medium of mosquito cells persistently infected with banzi virus. 19816164155
cell-mediated immunity in flavivirus infections. i. induction of cytotoxic t lymphocytes in mice by an attenuated virus from the tick-borne encephalitis complex and its group-reactive character.the lytic activity of splenocytes from c3h mice immunized with a highly attenuated line of langat virus [tick-borne encephalitis (tbe) complex] was determined by the in vitro 51cr release assay on tbe virus (western subtype)-infected target l929 cells. after the spleen cell suspensions were depleted of t cells with anti-mouse theta serum, or of b cells with anti-mouse immunoglobulin, the cytotoxic effect was found dependent on the presence of t lymphocytes. during immunization with langat virus, ...19816165230
evaluation of the solid-phase radioimmunoassay for diagnosis of st. louis encephalitis infection in humans.since the use of highly purified viral proteins in the solid-phase radioimmunoassay (spria) procedure is not practical for routine diagnostic serology, the procedure was adapted for use with the crude antigens now commonly used to diagnose st. louis encephalitis (sle) virus infections. sle and various other alpha- and flavivirus antigens were tested by both the spria procedure and conventional serological methods. standards were established for use of the crude antigens in the spria procedure. r ...19816168650
isolation of a replication-efficient mutant of west nile virus from a persistently infected genetically resistant mouse cell culture.flavivirus-resistant mouse embryofibroblasts (c3h/rv) that were infected with west nile virus, strain e101 (wnv), yielded fewer infectious virions than did cultures of congenic susceptible cells (c3h/he). analysis of intracellular viral rna synthesis indicated that the incorporation of [3h]uridine into 40s genome rna was markedly reduced in resistant cells, and about 100-fold less labeled 40s rna was found in pelleted extracellular virions from resistant cultures than in those from susceptible o ...19816168773
genetically controlled resistance to flavivirus and lactate-dehydrogenase-elevating virus-induced disease. 19816171382
interferon independence of genetically controlled resistance to flaviviruses.flavivirus-resistant c3h/rv mice injected with sheep anti-interferon globulin and then infected with either west nile or yellow fever virus survived and displayed no disease symptoms. also, treatment of embryo fibroblast cultures prepared from c3h/rv or congenic susceptible c3h/he mice with anti-interferon serum resulted in an increased yield of west nile virus from both types of cultures, but the amount of infectious virus produced by resistant cultures remained 1 to 1.5 logs lower than that pr ...19826176543
interferon-mediated persistent infection of saint louis encephalitis virus in a reptilian cell line.a persistent infection with saint louis encephalitis (sle) virus in a poikilothermic cell line th-1 (turtle heart cells) was studied. infected th-1 cells were subcultured weekly at 31 degrees c for 1 year and continued to produce low levels (10(2) to 10(3) p.f.u./ml) of virus without obvious cytopathic effects or marked cyclic events. indirect fluorescent antibody and infectious centre assays indicated that less than 1% of the cells were producing detectable virus proteins or infectious virus. d ...19826181191
homogeneity of the structural glycoprotein from european isolates of tick-borne encephalitis virus: comparison with other flaviviruses.isolates of tick-borne encephalitis (tbe) virus from finland, germany, czechoslovakia, switzerland and austria were compared with strains of the far eastern subtype isolated in russia as well as louping ill virus and other flaviviruses belonging to a different serocomplex: west nile, murray valley encephalitis and rocio viruses. analysis of the structural polypeptides by sds--polyacrylamide gel electrophoresis (sds--page) revealed identical mol. wt. of the glycoprotein e (mol. wt. 55 000) and th ...19816172553
antibody-dependent plaque enhancement: its antigenic specificity in relation to togaviridae.the antigenic specificity of antibody-dependent plaque enhancement (adpe) on the macrophage cell line p388d1 has been investigated using viruses in the flavivirus and alphavirus genera. whereas adpe detected group-specific antigenic determinants in the flaviviruses, narrower specificity (type and subgroup) was seen with alphaviruses. adpe titres correlated well with haemagglutination inhibition titres.19826174682
monoclonal antibodies to the structural glycoprotein of tick-borne encephalitis virus.hybridomas secreting antibodies to the structural glycoprotein of tick-borne encephalitis (tbe) virus were prepared by fusion of x63-ag8/653 mouse myeloma cells with spleen cells from mice immunized with purified glycoprotein complexes of tbe virus. these antibodies were tested against 10 different tbe virus strains isolated in different european countries over a period of 26 years from different hosts. quantitative evaluation of enzyme immunoassay results did not reveal any differences in react ...19826182103
interferon and antibody titrations using haemagglutinating togaviridae and trypsinized human erythrocytes.several togaviridae of the alphavirus and flavivirus genera agglutinate trypsinized human group o erythrocytes (thoe) (shortridge and hu, 1976). haemagglutinin titers of semliki forest virus (sfv) and japanese encephalitis virus (jev) measured with thoe were equivalent to, if not higher than, those obtained with embden gander erythrocytes, even with unextracted haemagglutinin. results obtained with thoe in jev haemagglutination-inhibition tests on sera taken from a previously infected individual ...19836189850
topographical analysis of antigenic determinants on envelope glycoprotein v3 (e) of japanese encephalitis virus, using monoclonal antibodies.ten monoclonal antibodies directed against envelope glycoprotein v3 (e) of japanese encephalitis virus were obtained. they were characterized by hemagglutination inhibition (hi), neutralization, and enzyme-linked immunosorbent assay and divided into four types: flavivirus-cross-reactive hi and non-neutralizing antibody (group 1), subgroup-specific hi and non-neutralizing antibody (group 2), low hi and neutralizing antibody (group 3), and non-hi and neutralizing antibody (groups 4 and 5, respecti ...19836185694
dialysable specific transfer factor in mice immunized with attenuated langat virus from the tick-borne encephalitis complex: generation, action and quantitative assay.cytolytic t lymphocyte assay was developed in order to measure the response of inbred c3h mice to dialysable specific transfer factor (stf), induced in subadult outbred mice by one shot immunization with the attenuated langat virus. the first stf activity in mice splenic leukocytes was detected between 48-72 hr after virus administration. the conversion of splenic t-cell cytotoxic response in c3h mice in vivo occurred between 15-21 hr after stf administration. the killing activity of t-cells, in ...19826188353
st. louis encephalitis virus temperature-sensitive mutants. i. induction, isolation and preliminary characterization.nine temperature-sensitive (ts) mutants of st. louis encephalitis virus were isolated after "forced mutagenesis" with 5-fluorouracil or 5-azacytidine. the ts mutants could be grouped on the basis of rna synthesis at 40 degrees c, the nonpermissive temperature and complementation analysis. four complementation groups were identified. members of two of the groups were negative for rna synthesis at 40 degrees c while the remainder were positive.19836188441
a topological and functional model of epitopes on the structural glycoprotein of tick-borne encephalitis virus defined by monoclonal antibodies.a topological and functional model of eight distinct epitopes on the structural glycoprotein of tick-borne encephalitis (tbe) virus was established by the use of monoclonal antibodies. the unique specificities and spatial relationships of these antibodies were determined by variant analysis, haemagglutination inhibition (hi), neutralization, passive mouse protection, and antibody blocking assays. seven out of the eight distinct epitopes were shown to be partially linked and to cluster in two ant ...19836190308
analysis of 17d yellow fever virus envelope protein epitopes using monoclonal antibodies.sixteen monoclonal antibodies that reacted with the envelope glycoprotein (e) of 17d vaccine strain yellow fever virus (17d yf), including two antibodies produced against dengue 2 virus, were used in a solid phase competitive binding assay (cba) to define spatial relationships among antigenic determinants on 17d yf e. the antibodies showed yf strain, type or flavivirus group specificities and nine epitopes were identified on 17d yf e by patterns of neutralization, haemagglutination inhibition an ...19846208313
[the course of flavivirus infections in mice in the presence of the graft versus host reaction under conditions of 2-way incompatibility].the graft versus host reaction (gvhr) under conditions of two-way incompatibility was shown to increase average longevity (al) of mice with experimental tick-borne encephalitis (tbe) and to activate asymptomatic infection caused by langat virus. experiments with tbe virus demonstrated participation of viable t lymphocytes in gvhr. inhibition of function of both humoral and cellular immunity was shown to occur in gvhr. the assumption that the increase in the average longevity in tbe is associated ...19806247848
enzyme linked immunosorbent assay (elisa) using beta-lactamase for the detection of antibodies to kfd virus. 19806248460
comparison of dengue viruses and some other flaviviruses by cdna-rna hybridization analysis and detection of a close relationship between dengue virus serotype 2 and edge hill virus.variable amounts of cdna were synthesized in vitro from rna extracted from several flaviviruses, including the four prototype dengue (den) virus serotypes. the synthesis was carried out using an oligo(dt) primer, suggesting the presence of a short poly(a) region at or near the 3' end of some flavivirus genomes. the den-1 and den-2 prototype strains produced the largest amount of cdna and were therefore used to investigate further the relatedness of flavivirus genomes by cdna-rna hybridization. t ...19846210345
serological response to formolized kyasanur forest disease virus vaccine in humans at sagar and sorab talukas of shimoga district. 19806249824
replication of flaviviruses: separation of membrane translation sites of kunjin virus proteins and of cell proteins. 19806251615
identification of epitopes on the e glycoprotein of saint louis encephalitis virus using monoclonal antibodies.twenty-one hybridomas producing monoclonal antibodies specific for the e glycoprotein of st. louis encephalitis (sle) virus, strain msi-7, have been isolated. serologic reactivities were initially determined by cross-reactivity indirect immunofluorescence assays using 22 strains of sle virus and 8 other related flaviviruses. four groups demonstrating type-, subcomplex-, supercomplex-, and group-specific reactivity patterns were identified. analysis of hemagglutination-inhibition (hi) and virus n ...19836192585
comparison of haemagglutination inhibition (hi) and indirect fluorescent antibody (ifa) techniques for the serological diagnosis of certain flavivirus infections.paired serum samples from 25 patients having clinical evidence of arboviral infections and 15 controls were examined for antibodies against dengue, japanese encephalitis and west nile viruses by haemagglutination inhibition (hi) and indirect fluorescent antibody (ifa) methods. the two tests were comparable in specificity but the ifa test was found to be more sensitive than the hi test. like the hi test, the antibodies detected by ifa test cross-reacted within the flavivirus group under test. use ...19806249938
turkey meningo-encephalitis in south africa.turkey meningo-encephalitis is a neuroparalytic disease of turkeys first described and shown to be caused by a flavivirus in israel. during 1978 a similar disease was observed in south africa. in addition to the lesions described in israel, myocarditis, regression of the ovary and egg peritonitis were constant findings. the similarity in host range, symptoms and pathological changes produced by the virus isolated locally and in israel and the serological cross-reaction between the 2 virus isolat ...19806251413
[comparative characteristics of reproduction of getah and west nile viruses in cell cultures of mosquitoes of 3 species]. 19806252429
[species-specific flavivirus antigens for the indirect hemagglutination reaction]. 19806252701
replication of tbe and langat viruses in cells from immune individuals.the replication of tbe virus and langat virus in cells of immune and non-immune individuals was compared in phytohemagglutinin (pha)-stimulated and non-pha-stimulated cultures and also following infection with low and high infection multiplicity. following infection of spleen cells from langat-immune mice with langat virus having a high infection multiplicity, higher virus replication rates than in non-immune cells were found to be present. replication of langat virus was generally superior to t ...19806252718
development of a kit for the assay of haemagglutination inhibition antibodies to flaviviruses using formalinized goose erythrocytes.haemagglutination inhibition (hi) test using goose erythrocytes (grbc) is the method of choice for screening antibodies to various arboviruses. this test makes use of fresh grbc preserved in dextrose-gelatin-veronal (dgv). we have tried formalinizing grbc and have found that such cells can retain the surface property of being agglutinated by arboviruses and, therefore, can be used in haemagglutination (ha) and hi tests. unlike fresh cells preserved in dgv, formalinized cells can be preserved for ...19806254214
a micro-neutralization test for flavivirus antibodies.a micro-neutralization test for the detection of flavivirus antibodies is described. the test utilizes the ps line of cells in flat bottomed microtiter plates to detect the neutralization of cytopathic effect by specific antibodies. cross-neutralization of flaviviruses found in southeast asia with homologous and heterologous hyperimmune mouse ascitic fluids revealed the test to be specific. the test is simple and inexpensive to perform.19806254186
variation in virulence for mice and rhesus monkeys among st. louis encephalitis virus strains of different origin.the virulence characteristics of 67 strains of st. louis encephalitis (sle) virus isolated from various sources in north, middle, and south america were compared in mice and rhesus monkeys. each virus strain was titrated in mice exactly 21 days old and virulence was expressed as the ratio of intracerebral (ic)/intraperitoneal (ip) ld50. virus strains fell into three groups: 1) high virulence (ic/ip ld50 ratio approximately 1.0); 2) intermediate virulence (variable mortality over a wide dose rang ...19806254384
[tick-borne encephalitis in europe (author's transl)].tick-borne encephalitis is the major european arbovirosis. it is observed in soviet union, central and western europe and scandinavian countries. in france, natural foci have been detected in alsace (more specialy in illkirch forest, near strasbourg). in the united kingdom exists a sheep encephalomyelitis (loupingill) caused by an arbovirus not much different from the tick-born encephalitis virus. the tick-born encephalitis virus is a flavivirus transmitted by tick bites. tick is also a virus re ...19806255281
towards prediction and surveillance of murray valley encephalitis activity in australia.current practices for early warning of activity of murray valley encephalitis and other medically-important arboviruses are reviewed with view to improvement. data from previous papers on culex annulirostris populations, environmental factors and virus infection rates were reanalysed and the results considered as a basis for prediction and surveillance. this goal will only be achieved with improved national cooperation, a better epidemiological understanding and greater knowledge of the bionomic ...19806255919
serological survey for human arbovirus infections in the province of quebec. 19806256047
method to detect asymptomatic carriers of simian hemorrhagic fever virus.evidence was obtained that mononuclear phagocytic cells are the target cells for simian hemorrhagic fever virus replication. using peritoneal macrophages from rhesus monkeys in an in vitro, 18 of 20 asymptomatic chronically infected patas monkeys were detected from coded samples. the two chronically infected patas monkeys not detected by the test, nevertheless, contained virus. this was determined by inoculating macrophage cultures with plasma from macaques dying as a result of inoculation with ...19806257971
[serological evaluation of vaccine against human encephalitis caused by rocio virus]. 19806258211
effect on mice of infection during pregnancy with three australian arboviruses.infection of pregnant mice with ross river or getah viruses after the establishment of a functional placenta resulted in fetal infection with these viruses. however, only with ross river virus was there any significant fetal death. there was significant post-partum mortality in mice infected in utero with ross river but not with getah virus. in contrast, significant post-partum mortality occurred in murray valley encephalitis virus-infected mice despite the inability of the virus to cross the pl ...19816259957
nomenclature of flavivirus-specified proteins.flavivirus structural proteins are designated e, c, and m, replacing the former nomenclature of v3 (envelope), v2 (core), and v1 (membrane-like) proteins, respectively. the nonstructural proteins, formerly nv1 through nv5, are designated by their apparent size in kilodaltons, prefixed by p (or gp if a glycoprotein), if they are stable unrelated end-products; the lower case p or gp is used for variants or uncharacterized products. a relationship to any structural protein is indicated by adding e, ...19806259086
isolation of st. louis encephalitis virus from a patient in belém, louis encephalitis (sle) virus was isolated from a 21-year-old female hospitalized on 4 october 1978 in belém, brazil. symptomatology on admission included fever, chills, severe headache, abdominal pain, myalgia, arthralgia and jaundice. sle virus was isolated from her blood drawn on the 8th day of illness and subsequent seroconversion was documented. serological tests showed the isolate to be closely related to the belém prototype of sle virus but distinct from other flaviviruses tested. th ...19816259956
synthesis of glycoproteins in cells infected by the flavivirus kunjin. 19816259820
variation among strains of st. louis encephalitis virus: basis for a genetic, pathogenetic, and epidemiologic classification. 19806261645
mosquito cells infected with banzi virus secrete an antiviral activity which is of viral origin. 19816261449
serological evidence of arboviral infections (flaviviruses) in kerala. 19806262227
transovarial transmission of murray valley encephalitis virus by aedes aegypti (l).in laboratory studies, murray valley encephalitis virus was transmitted transovarially by orally infected aedes aegypti to approximately 1.5% of both adult male and female progeny.19806263238
wesselsbron disease: virological and serological studies in experimentally infected sheep and sheep and goats and new-born lambs and kids were experimentally infected with a wesselsbron disease virus. the viraemia in lambs commenced approximately 27 h after infection and lasted on the average for 50 h. a febrile reaction, which was mostly biphasic, commenced several hours after the viraemia and outlasted it by 50 h. the viraemia in adult animals began about 50 h after infection and lasted for 30 h. the fever usually commenced several hours after the viraemia and, as in 3 cases out ...19806262694
attenuated langat e5 virus as a live virus vaccine against kyasanur forest disease virus. 19816263797
persistence of humoral immunity in kyasanur forest disease. 19816263796
potential use of attenuated langat e5 virus as a live vaccine -- long term protection against russian spring-summer encephalitis virus in mice.a single inoculation of langat e5 virus provides 90-100% protection in mice against 3200-16000 lethal doses of russian spring-summer encephalitis (rsse) virus when challenged 18 or 24 months later. the observed protection is found in the absence of neutralizing antibody (na) against rsse virus at the time of challenge but is associated with anamnestic na response. immunized mice have low titer short duration viremia. immunized mice have late first detection and much lower multiplication in the b ...19816265549
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