Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| dengue type-2 virus envelope protein made using recombinant baculovirus protects mice against virus challenge. | the gene coding for the envelope (e) glycoprotein of dengue-2 virus was cloned into baculovirus (autographa californica nuclear polyhedrosis virus). the recombinant virus contained the entire e protein gene, preceded by 38 nucleotides from the end of the prematrix glycoprotein gene and followed by the first 83 nucleotides of nonstructural protein 1. when expressed in spodoptera frugiperda (sf9) cells, approximately 1 mg of recombinant e antigen was made per 10(9) cells. this antigen reacted with ... | 1994 | 8147490 |
| dengue infection complicated by severe hemorrhage and vertical transmission in a parturient woman. | a thai woman with a febrile illness was delivered of a healthy infant by cesarean section. the etiology of her 2-day fever was unknown at the time of surgery; results of serology performed later established a diagnosis of dengue infection. postoperative hemostatic monitoring was not performed. she experienced massive and prolonged (8 days) wound hemorrhage that necessitated multiple transfusions of blood, platelets, and frozen plasma. the newborn became febrile on his 6th day of life. dengue vir ... | 1994 | 8161636 |
| glycosylation mutants of dengue virus ns1 protein. | the non-structural glycoprotein ns1 of dengue virus type 2 contains sites for n-linked glycosylation at asn-130 and asn-207. ns1 synthesized in infected cells is glycosylated at both locations. we have now examined the dimerization and secretion of ns1 lacking one or both of these sites by transient expression of mutagenized cdna inserted into a simian virus 40-based vector. immunoblotting and radioimmunoprecipitation were used to detect ns1 associated with transfected cells and in the extracell ... | 1994 | 8176380 |
| active immunization by a dengue virus-induced cytokine. | dengue type 2 virus (dv)-induced cytotoxic factor (cf) is capable of reproducing various pathological lesions in mice that are seen in human dengue. the present study was undertaken to investigate the protective effect of active immunization of mice with cf. mice were immunized with 5 microgram of cf and prevention of cf-induced increase in capillary permeability and damage to the blood-brain barrier were studied at weekly intervals, up to 48 weeks, by challenging with 3 microgram of cf. maximum ... | 1994 | 8187327 |
| development of a nested-pcr test based on sequence analysis of epizootic hemorrhagic disease viruses non-structural protein 1 (ns1). | two orbiviruses, epizootic hemorrhagic disease (ehd) and bluetongue (btv) viruses, cause disease in domestic and wild ruminant species. the gene that encodes non-structural protein 1 (ns1) of ehd virus, serotype 1, was sequenced and compared to ehd and btv ns1 sequences. the ns1 gene was found to be more conserved than the vp3 gene, and was selected as a target for polymerase chain reaction (pcr) amplification. the ns1 genes of several btv viruses and another orbivirus, african horse sickness (a ... | 1994 | 8191788 |
| phylogenetic relationships of dengue-2 viruses. | rna oligonucleotide fingerprinting studies on a large number of virus isolates previously demonstrated considerable genetic variation in isolates of dengue (den)-2 serotype. we report the entire envelope (e) glycoprotein gene and deduced amino acid sequences of 16 den-2 viruses and the phylogenetic relationships of these, plus 17 additional published den e gene sequences. comparison of den-2 e glycoprotein gene sequences revealed base substitutions scattered throughout the entire gene with as mu ... | 1993 | 8212556 |
| role of protein conformation in the processing of dengue virus type 2 nonstructural polyprotein precursor. | the dengue virus type-2 (den-2) genome is a positive-strand rna encoding a single polyprotein precursor, c-prm(m)-e-ns1-ns2a-ns2b-ns3-ns4a-ns4b- ns5, consisting of 3391 amino acids (aa). the n-terminal region of the polyprotein precursor, c-prm(m)-e, encodes the structural proteins and is processed cotranslationally by the host signal peptidase. the nonstructural region ns1-->ns5 is processed by the viral protease(s), as well as by the signal peptidase. a two-component viral protease consisting ... | 1993 | 8325506 |
| dengue virus-specific human cd4+ t-lymphocyte responses in a recipient of an experimental live-attenuated dengue virus type 1 vaccine: bulk culture proliferation, clonal analysis, and precursor frequency determination. | we analyzed the cd4+ t-lymphocyte responses to dengue, west nile, and yellow fever viruses 4 months after immunization of a volunteer with an experimental live-attenuated dengue virus type 1 vaccine (den-1 45az5). we examined bulk culture proliferation to noninfectious antigens, determined the precursor frequency of specific cd4+ t cells by limiting dilution, and established and analyzed cd4+ t-cell clones. bulk culture proliferation was predominantly dengue virus type 1 specific with a lesser d ... | 1993 | 8371350 |
| the effects of site-directed mutagenesis on the dimerization and secretion of the ns1 protein specified by dengue virus. | cdna of dengue virus type 2 encoding the glycoprotein ns1 was transiently expressed in cos cells using an sv40-based vector. to test the importance of selected regions of the protein in dimer formation, constructs were prepared which encoded amino acid changes at specific locations. six of the 12 cys residues in the ns1 protein were individually changed to ala. two amino acids in each of three hydrophilic and two hydrophobic areas of the protein were also changed to ala. the ability of these 11 ... | 1993 | 8389081 |
| synthesis of dengue virus rna in vitro: initiation and the involvement of proteins ns3 and ns5. | an assay for flavivirus rna-dependent rna polymerase activity in vitro was established using extracts of vero cells infected with dengue virus type 2 (den-2) or kunjin virus (kun). rna synthesis was initiated on a template of viral replicative form (rf) and rf was converted to the replicative intermediate (ri). the rna-dependent rna polymerase complex of den-2 utilised either den-2 or kun rf as template, and similarly the kun polymerase complex utilised either den-2 or kun rf template. in additi ... | 1993 | 8418788 |
| high-level expression of the japanese encephalitis virus e protein by recombinant vaccinia virus and enhancement of its extracellular release by the ns3 gene product. | recombinant vaccinia viruses expressing the prm and e genes of the japanese encephalitis virus (jev) were constructed by use of synthetic promoters. while the recombinant virus moj6-sl, with an optimized vaccinia late-gene promoter, produced a 20-fold elevated level of e protein, as well as an 86-kda precursor protein in infected cells, no significant quantitative difference was detected between the extracellular or cell-surface e protein produced by moj6-sl and those produced by moj6 with the 7 ... | 1993 | 8421896 |
| immunoreactivity and protective effects in mice of a recombinant dengue 2 tonga virus ns1 protein produced in a baculovirus expression system. | the double-stranded replicative form of dengue 2 virus (den-2) rna (tonga strain) was used as a substrate to produce dna clones of the ns1-ns2a genes via reverse transcriptase synthesis of full length cdna followed by polymerase chain reaction amplification of the ns1-ns2a region. products were cloned into ptz18r for sequencing and into baculovirus for expression studies. the deduced amino acid sequence of the ns1-ns2a was almost identical to that of the s1 attenuated strain of den-2 puerto rico ... | 1993 | 8423452 |
| processing of the dengue virus type 2 proteins prm and c-prm. | a glycoprotein c-prm of 35,000 m(r) was immuno-precipitated from lysates of aedes albopictus cells infected with dengue virus type 2 (den-2) using antisera directed against the c protein or an amino-terminal fragment of the prm glycoprotein. c-prm was not detected in infected vero cells. the prm glycoprotein synthesized in infected a. albopictus and vero cells was cleaved to produce the membrane-associated virion protein (m) and the non-m fragment (pr) immediately preceding or occurring simultan ... | 1993 | 8429301 |
| dengue 2 virus ns2b and ns3 form a stable complex that can cleave ns3 within the helicase domain. | flavivirus genomic rna is translated into a large polyprotein that is processed into structural and nonstructural proteins. the n-termini of several nonstructural proteins are produced by cleavage at dibasic sites by a two-component viral proteinase consisting of ns2b and ns3. ns3 contains a trypsin-like serine proteinase domain at its n-terminus, whereas the function of ns2b in proteolysis is yet to be determined. we have used an ns3-specific antiserum, under nondenaturing conditions, to demons ... | 1993 | 8460492 |
| direct sequencing of genomic cdna fragments amplified by the polymerase chain reaction for molecular epidemiology of dengue-2 viruses. | a nucleotide fragment encoding amino acids 29 to 94 in the e-protein of 28 dengue-2 isolates of diverse geographic and host origins was examined by direct sequencing of a polymerase chain reaction (pcr)-amplified product, and compared to six previously published sequences. nucleotide divergence ranged from 0 to 19.8% corresponding to a maximum of 9% divergence in the amino acid sequence. taking a divergence of 6% between the nucleotide sequence as a cut off for genotype classification, six group ... | 1993 | 8470950 |
| sequence of the dengue virus type 2 (strain pr-159) ns1 gene and comparison with its vaccine derivative. | 1993 | 8479921 | |
| selection and partial characterization of dengue 2 virus mutants that induce fusion at elevated ph. | two types of dengue (den) 2 virus mutants were selected either by repeated exposure to acidic ph (acid mutant, am), or by the addition of ammonium chloride to aedes albopictus c6/36 cells prior to and during viral infection (fusion mutant, fm). both mutants grew more slowly than the parent strain and induced smaller plaques in vero cells. the 50% fusion from within index for both mutants occurred at least 0.65 ph units higher than with the wild-type den virus. a single amino acid substitution (a ... | 1993 | 8480420 |
| effect of adjuvants on immunization with dengue virus-induced cytotoxic factor. | specific active immunization with dengue type 2 virus (dv)-induced cytokine, cytotoxic factor (cf), prevents cf-mediated pathology in mice. the present study was undertaken to determine the optimum dose of cf and the effect of different adjuvants on the immune response as assessed by the study of anti-cf antibody titre by elisa and protection against increase in capillary permeability to challenging dose of 3 micrograms cf. the maximum protection of 94 +/- 4% against increase in capillary permea ... | 1995 | 8536363 |
| evaluation of enemas for exposing aedes aegypti to suspensions of dengue-2 virus. | to determine if enemas could be used to simulate oral exposure of aedes aegypti to dengue-2 virus, we compared infection rates of mosquitoes administered an enema of a blood suspension containing dengue-2 virus to infection rates in mosquitoes that imbibed the same suspension from a drop of blood. in 1 of 4 experiments infection rates were significantly different. more importantly, during 2 of the 4 trials, 100% of the mosquitoes in the enema treatment group were infected. we speculate that the ... | 1995 | 8551311 |
| failure of immune sera to neutralize dengue-2 virus in intrathoracically inoculated aedes aegypti. | aedes aegypti became infected when inoculated with a mixture of dengue-2 virus and anti-dengue-2 antibodies, but not when they were exposed to the same mixture per os. this phenomenon merits more detailed investigation. understanding why this difference in mosquito infection rate occurs may lead to improved dengue virus assays or provide insights into the nature of dengue virus-antibody interactions. | 1995 | 8551312 |
| mice immunized with a dengue type 2 virus e and ns1 fusion protein made in escherichia coli are protected against lethal dengue virus infection. | a gene fragment encoding the c-terminal 204 amino acids (aa) from the structural envelope glycoprotein (e) and the n-terminal 65 aa from non-structural protein one (ns1) of dengue type 2 virus (den-2) was expressed in escherichia coli (e. coli) as a fusion protein with staphylococcal protein a. the recombinant fusion protein was purified and analysed for its antigenicity, its immunogenicity and its ability to protect mice against lethal challenge with live den-2 virus. the recombinant protein wa ... | 1995 | 8578812 |
| genetically engineered resistance to dengue-2 virus transmission in mosquitoes. | the control of arthropod-borne virus diseases such as dengue may ultimately require the genetic manipulation of mosquito vectors to disrupt virus transmission to human populations. to reduce the ability of mosquitoes to transmit dengue viruses, a recombinant sindbis virus was used to transduce female aedes aegypti with a 567-base antisense rna targeted to the premembrane coding region of dengue type 2 (den-2) virus. the transduced mosquitoes were unable to support replication of den-2 virus in t ... | 1996 | 8629025 |
| pathogen-derived resistance to dengue type 2 virus in mosquito cells by expression of the premembrane coding region of the viral genome. | the full-length premembrane (prm) coding region of the dengue virus type 2 (den-2; jamaica) genome was expressed in c6/36 (aedes albopictus) cells in either the sense or the antisense orientation from a double subgenomic sindbis (dssin) virus. northern (rna) blot analysis confirmed the expression of sense or antisense den-2 prm rna in infected c6/36 cells. prm protein was demonstrated in cells infected with dssin virus expressing den-2 sense rnas by an immunofluorescence assay. c6/36 cells were ... | 1996 | 8642634 |
| dengue-2 virus infection of human bone marrow: characterization of dengue-2 antigen-positive stromal cells. | dengue is often associated with neutropenia and thrombocytopenia, suggesting that cells of the bone marrow may be targets of dengue viral infections. in this study we infected long-term marrow cultures with dengue type-2 (den-2) virus and characterized the viral antigen-positive cells. using immunofluorescence microscopy and immunohistochemical staining, we demonstrated two types of stromal cells that were positive for den-2 virus antigens. the first was a population of relatively small (approxi ... | 1996 | 8644906 |
| immunolocalization of the dengue virus nonstructural glycoprotein ns1 suggests a role in viral rna replication. | although many workers have investigated the maturation and processing of the flavivirus nonstructural glycoprotein ns1 in infected cells, these studies have provided little insight into a possible function for ns1. in this study we investigated the subcellular localization of ns1 both by immunofluorescence and cryo-immuno electron microscopy of infected vero and c6/36 cells. ns1 was found to be tightly associated with intracellular membranes, in particular with vesicle packets and large cytoplas ... | 1996 | 8659120 |
| langerhans cell density and serological changes following intradermal immunisation of mice with dengue 2 virus. | after the introduction of the dengue-2 (16681) virus by intradermal (i.d.) injection into the footpads of mice, langerhans cells (lcs) increased in numbers within 24 h at the site of injection and neutralising antibody developed. on comparing the i.d. and intramuscular (i.m.) routes, antibody was produced more rapidly and at higher levels when the virus was injected by the i.d. route. subsequent re-challenge by the i.d. route produced an even more rapid serological response with all mice produci ... | 1996 | 8683550 |
| a higher production of platelet activating factor in ex vivo heterologously secondary dengue-2 virus infections. | patients with a dengue-1 virus (dv-1) infection followed by another dv-2 infection were reported to have a higher incidence of dengue haemorrhagic fever (dhf). mononuclear leukocytes (mnls) are principal cells for dv replication so that we challenge mnls obtained from non-immune and previously dv-1-infected donors with dv-2 to mimic primary and heterologously secondary dv-2 infections. production of platelet activating factor (paf), thromboxane b2 (txb2), and prostaglandin d2 (pgd2) by mnls in t ... | 1995 | 8689093 |
| dengue type 2 outbreak in the south of the state of bahia, brazil: laboratorial and epidemiological studies. | during march 1994 cases of a exanthematic acute disease were reported in the municipalities of itagemirim, eunápolis and belmonte, state of bahia. dengue fever was confirmed by serology (mac-elisa) and by dengue virus type 2 isolation, genotype jamaica. signs and symptoms of classic dengue fever were observed with a high percentual of rash (73.8%) and pruritus (50.5%). major haemorrhagic manifestations were unfrequent and only bleeding gum was reported. dengue virus activity spreaded rapidly to ... | 1995 | 8731263 |
| ultrastructural aspects of the replication of dengue virus type 2 isolated in brazil. | 1996 | 8736101 | |
| surveillance of the mosquito aedes aegypti and its biocontrol with the copepod mesocyclops aspericornis in australian wells and gold mines. | a survey of the dengue vector mosquito aedes aegypti was undertaken using funnel traps to detect immature stages (larvae and pupae) in flooded disused mine shafts and wells in charters towers, queensland, northern australia. the town has a history of dengue fever since 1885 when goldminers were the first recorded victims. during the latest dengue epidemic in 1993, 2% of the population had laboratory-confirmed dengue virus type 2, despite source reduction of ae.aegypti breeding-sites at ground le ... | 1996 | 8744708 |
| epidemic dengue 2 in the city of djibouti 1991-1992. | from october 1991 to february 1992, an outbreak of acute fever (in which thick blood films were negative for malaria) spread rapidly in the city of djibouti, djibouti republic, affecting all age groups and both nationals and foreigners. the estimated number of cases was 12,000. the clinical features were consistent with a non-haemorrhagic dengue-like illness. serum samples from 91 patients were analysed serologically for flavivirus infection (dengue 1-4, west nile, yellow fever, zika, banzi, and ... | 1996 | 8758061 |
| dengue virus-induced cytotoxin releases nitrite by spleen cells. | dengue type-2 virus (dv) infection in mice induces t cells to produce a cytokine, the cytotoxic factor (cf), which induces h2-a positive macrophages to produce another cytokine, cyototoxic (cf2), which amplifies its cytotoxic effects on target cells. the present study was undertaken to investigate the production of nitrite (no2-) by the spleen cells of mice in vitro and in vivo following inoculation of cf2. maximum no2- production occurred at 1 hour after inoculation of 100 micrograms cf2. pretr ... | 1996 | 8762862 |
| serological evidence of den-2 activity in assam and nagaland. | 1996 | 8778182 | |
| flow cytometric analysis of t4:t8 splenic cell during dengue virus infection of mice. | the present study was undertaken to investigate the effect of dengue type 2 virus (dv) and dv-induced cytokines (cf and cf2) on t lymphocyte subpopulations of spleen by flow cytometry. following dv-ic inoculation in mice the percent number of cd4+ and cd8+ lymphocytes in the spleen was reduced, the peak reduction in both was observed on the 6th day post-inoculation (p.i.). intravenous inoculation of cf or cf2 in mice also decreased the percent number of cd4+ as well as cd8+ t lymphocytes subpopu ... | 1995 | 8786153 |
| multiple specificities in the murine cd4+ and cd8+ t-cell response to dengue virus. | the target epitopes, serotype specificity, and cytolytic function of dengue virus-specific t cells may influence their theoretical roles in protection against secondary infection as well as the immunopathogenesis of dengue hemorrhagic fever. to study these factors in an experimental system, we isolated dengue virus-specific cd4+ and cd8+ t-cell clones from dengue-2 virus-immunized balb/c mice. the t-cell response to dengue virus in this mouse strain was heterogeneous; we identified at least five ... | 1996 | 8794288 |
| mutational analysis of a neutralization epitope on the dengue type 2 virus (den2) envelope protein: monoclonal antibody resistant den2/den4 chimeras exhibit reduced mouse neurovirulence. | the antigenic site of dengue type 2 virus (den2)-neutralizing monoclonal antibody (mab) 3h5 was investigated by mutational analysis. sequence comparisons indicated that much of the 12-amino-acid sequence extending from position 386 to 397 of the den2 envelope glycoprotein (e) previously thought to represent the den2-specific mab 3h5 binding site was also present in some dengue type 1, 3, or 4 virus strains. however, the region occupied by the glu-pro-gly sequence at upstream positions 383 to 385 ... | 1996 | 8874504 |
| dengue virus envelope glycoprotein can be secreted from insect cells as a fusion with the maltose-binding protein. | the maltose-binding protein (male) contains a signal sequence which allows its translocation in the periplasm of prokaryotic microorganisms. in this study, male was produced in spodoptera frugiperda (sf9) lepidopterian cells using the baculovirus expression system. the secretion of male, following cleavage of its signal sequence, to the supernatant fluid of recombinant baculovirus-infected sf9 cells and its affinity for maltodextrin polymers allowed recovery of significant amounts (> or = 10 mic ... | 1996 | 8882648 |
| a single nucleotide change in the e protein gene of dengue virus 2 mexican strain affects neurovirulence in mice. | eleven clones of dengue virus 2 mexican strain were selected by the size of their lytic plaques. nucleotide sequences of the clones producing large plaques (d2ml2, d2ml3 and d2ml4) revealed 11 mutations, 10 of which were silent. the substitution at nucleotide 1168 (g-->c) generates one amino acid difference at residue 390 (asp-->his) of the envelope protein (e). these clones showed high virulence in suckling mice when inoculated intracerebrally (> or = 70% mortality). however, the clones which s ... | 1996 | 8887488 |
| susceptibility of laboratory-bred rodents to the experimental infection with dengue virus type 2. | various strains of laboratory-bred rodents viz. mice [swiss, c57bl/6, c3h/hej, dba/2, balb/c, nmri (nu/nu) and bl6 (nu/nu) and their heterozygous siblings (nu/+)], mastomys natalensis, wistar rat, golden hamster and indian desert gerbil were inoculated intracerebrally (ic) with mouse-adapted dengue virus type 2 (dv-2). the inoculated animals were observed daily for dullness, anorexia, occult blood in faeces, patechial haemorrhages, lacrymation, paralysis, cachexia, death. necropsied animals were ... | 1996 | 8891094 |
| development of a purified, inactivated, dengue-2 virus vaccine prototype in vero cells: immunogenicity and protection in mice and rhesus monkeys. | the feasibility of a purified, inactivated dengue (den) vaccine made in vero cells was explored. a den-2 virus candidate was chosen for production of a monotypic, purified, inactivated vaccine (piv). virus was harvested from roller bottle culture supernatants, concentrated, and purified on sucrose gradients. the purified virus was inactivated with 0.05% formalin at 22 degrees c. after inactivation, the virus retained its antigenicity and was immunogenic in mice and rhesus monkeys, in which it el ... | 1996 | 8940206 |
| immunogenic and protective response in mice immunized with a purified, inactivated, dengue-2 virus vaccine prototype made in fetal rhesus lung cells. | the feasibility of a purified, inactivated vaccine (piv) against dengue type 2 (den-2) virus was explored. dengue-2 virus strain 16681 was used for producing a monotypic piv. virus adapted to fetal rhesus lung (frhl-2) cells was harvested from roller bottle culture supernatant fluids, concentrated, and purified on sucrose gradients. analysis of purified virus preparations by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blotting showed primarily envelope (e) and premembra ... | 1996 | 8940981 |
| identification and characterization of receptor for dengue virus-induced macrophage cytotoxin. | the present study was undertaken to identify the receptor for dengue virus type 2 (dv) induced macrophage cytotoxin (cf2) on mouse peritoneal macrophages (mphi). the binding of 125i-labelled cf2 to mphi was saturable (15 nm), reversible, temperature, ph- and time-dependent. the saturation concentration was similar to that causing cell death. scatchard analysis showed the presence of intermediate type of affinity receptor and the number of receptor sites was 1.1 x 10(6) per cell with dissociation ... | 1996 | 8979500 |
| internal proteolysis of the ns3 protein specified by dengue virus 2. | the ns3 protein of flaviviruses is a multifunctional polypeptide required for virus replication. enzymic activities that have been demonstrated or predicted from the presence of sequence motifs include protease, ntpase, helicase and rna triphosphatase. both full-length and truncated forms of ns3 have been identified in infected cells. to examine internal cleavage of the ns3 protein of dengue virus 2 (den-2), infected cells or cos cells transfected with cdna encoding ns2b/3 were radiolabelled and ... | 1997 | 9018055 |
| maturation of the dengue-2 virus ns1 protein in insect cells: effects of downstream ns2a sequences on baculovirus-expressed gene constructs. | a series of recombinant baculoviruses was constructed in order to study the influence of downstream ns2a sequences on the processing of the dengue virus ns1 glycoprotein in insect cells. ns1 alone was expressed at a high level in its native dimeric form and processed efficiently through the spodoptera frugiperda (sf) cell secretory pathway. recombinant ns1 was found associated with the plasma membrane and was also secreted into the extracellular medium. although both intra- and extracellular ns1 ... | 1995 | 9049346 |
| production of nitrite by dengue virus-induced cytotoxic factor. | dengue type 2 virus (dv) infection induces production of a cytokine, the cytotoxic factor (cf) in the spleen of mice. the present study was undertaken to investigate the production of nitrite (no2-) by the spleen cells of mice in vitro and in vivo following inoculation of dv or cf. maximum no2- production occurred at 45 min after inoculation of 5 microg cf, both in vitro and in vivo. the no2- was produced by macrophages and t cells and not by b cells. pretreatment of cf with anti-cf antisera inh ... | 1996 | 9099923 |
| genotype determination of three dengue type 2 virus strains from myanmar by sequencing e/nsi gene junction. | genotype of three dengue-2 virus strains from myanmar was determined as genotype ii by sequencing 240 nucleotide long fragment across the e/ns1 gene junction by the primer extension dideoxy chain termination method, applying direct sequencing of the pcr product. these strains were isolated from a dengue shock syndrome (dss) patient and two patients with dengue hemorrhagic fever (dhf) grade 1, in yangon (rangoon), myanmar (burma), in 1987. sequence homology of all three strains were highest (96%) ... | 1995 | 9139372 |
| anti-dengue igg detection by an indirect elisa. | protein-free culture media were originally developed for hybridomas to simplify downstream processing and purification. for the same reasons, we have used these protein-free media for passaging dengue 2 virus in c6/36 cells. this provided us with an infected supernatant (denpf) which could then be used as coating antigens for an indirect enzyme-linked immunosorbent assay (elisa) to determine dengue igg levels. using this preparation, the main immunogenic band as seen by immunoblot appeared to be ... | 1995 | 9139374 |
| origins of dengue type 2 viruses associated with increased pathogenicity in the americas. | the recent emergence and spread of dengue hemorrhagic fever in the americas have been a major source of concern. efforts to control this disease are dependent on understanding the pathogenicity of dengue viruses and their transmission dynamics. pathogenicity studies have been hampered by the lack of in vitro or in vivo models of severe dengue disease. alternatively, molecular epidemiologic studies which associate certain dengue virus genetic types with severe dengue outbreaks may point to strain ... | 1997 | 9143280 |
| construction of infectious cdna clones for dengue 2 virus: strain 16681 and its attenuated vaccine derivative, strain pdk-53. | we identified nine nucleotide differences between the genomes of dengue-2 (den-2) 16681 virus and its vaccine derivative, strain pdk-53. these included a c-to-t (16681-to-pdk-53) mutation at nucleotide position 57 of the 5'-untranslated region, three silent mutations, and substitutions prm-29 asp to val, ns1-53 gly to asp, ns2a-181 leu to phe, ns3-250 glu to val, and ns4a-75 gly to ala. unpassaged pdk-53 vaccine contained two genetic variants as a result of partial mutation at ns3-250. we constr ... | 1997 | 9143286 |
| inoculation of plasmids expressing the dengue-2 envelope gene elicit neutralizing antibodies in mice. | to develop a nucleic acid vaccine against dengue type-2 virus, the prem and 92% of the envelope (e) genes were cloned into different eukaryotic plasmid expression vectors (pkcmvint polyli and pvr1012). the resultant plasmid constructs (pd2me and p1012d2me) properly expressed the truncated e protein in vitro as evidenced by the expected protein size on sds-page and the ability of the protein to be recognized by monoclonal antibodies directed against conformational epitopes. three-week-old balb/c ... | 1997 | 9160523 |
| risk factors in dengue shock syndrome. | despite a growing body of evidence predominantly, but not exclusively, from thailand suggesting that the risk of developing dengue shock syndrome (dss) is greatest following an anamnestic dengue infection, particularly if the most recent infection was with dengue 2 virus, there continues to be debate about the justification for these claims. this report describes a five-year, prospective study in two townships (suburbs) in yangon (rangoon) myanmar (burma) in which attempts were made to confirm t ... | 1997 | 9180609 |
| infectious rna transcripts from full-length dengue virus type 2 cdna clones made in yeast. | the dengue virus type 2 genomic rna was amplified by reverse transcription-pcr and cloned as four cdna fragments. we could not assemble these four fragments into full-length cdna in escherichia coli. the full-length dengue virus cdna was constructed by homologous recombination in yeast, either as part of a yeast artificial chromosome or in a yeast-e. coli shuttle vector. full-length cdna clones were propagated once in e. coli to prepare useful quantities of dna. in vitro transcription of these c ... | 1997 | 9188607 |
| the dengue virus nonstructural-1 protein (ns1) generates antibodies to common epitopes on human blood clotting, integrin/adhesin proteins and binds to human endothelial cells: potential implications in haemorrhagic fever pathogenesis. | antibody responses generated by mice to the dengue-2 virus ns1 protein (d-2v ns1) were influenced by mhc class ii (i-a) haplotype but each antiserum cross-reacted with human fibrinogen, thrombocytes and endothelial cells. to investigate these findings, a highly avid subclone (mab 1g5.4-a1-c3) was selected from a parent hybridoma that secreted a monoclonal antibody (mab) specific for the native dimeric form of d-2v ns1. when mab reactions were compared using a panel of overlapping synthetic pepti ... | 1997 | 9191856 |
| possible occurrence of a genetic bottleneck in dengue serotype 2 viruses between the 1980 and 1987 epidemic seasons in bangkok, thailand. | cocirculation of two genetic subtypes of dengue serotype 2 viruses was first observed in the 1980 epidemic season in thailand. to further delineate the evolutionary history and the contribution of these subtypes to subsequent epidemics, we determined the envelope glycoprotein gene sequence of 20 dengue serotype 2 viruses isolated from infected patients during 1987 and compared them with those derived from earlier years. subtype iiia strains represented the majority (18 of 19) of dengue type 2 vi ... | 1997 | 9242328 |
| [reconstitution of hu-scid mice transplanted with human tonsillar lymphocytes immunized with dengue virus-2 in vitro and its immune response]. | to study the measure for the reconstitution of severe combined immunodeficient disease mice (scid mice) transplanted with human lymphocytes immunized with specific antigen in vitro. | 1996 | 9275474 |
| monoclonal antibodies raised to the dengue-2 virus (cuban: a15 strain) which recognize viral structural proteins. | mouse monoclonal antibodies (mabs) were raised to dengue-2 virus (d-2v) cuban (a15) strain and the cell culture supernatants were screened by elisa using the homologous virus. three mab-secreting lines were further characterized using immunoblot, haemaglutination, complement-fixation, and neutralization assays. one of these, mab 8h8, weakly reacted with the viral nonstructural-1 protein (ns1) but more specifically identified the capsid protein (c), mab 3e1 recognized in serological assays d-2v a ... | 1997 | 9309425 |
| activity of dengue-2 virus and prevalence of aedes aegypti in the chirimiri colliery area, madhya pradesh, india. | repeated outbreaks of a suspected viral fever in chirimiri colliery area, madhya pradesh were reported since 1990. the area consists of an agglomeration of sprawling settlements at varying altitudes of 816 to 890 m and it has partial sylvan cover. during a 1992 outbreak 25 patients' sera were tested, of which 13 showed seropositivity to dengue (den) by mac-elisa test; den-2 was isolated from aedes aegypti collected from two of the eight settlements of the area. the principal vector, ae. aegypti, ... | 1997 | 9322295 |
| dengue infection in paracambi, state of rio de janeiro, 1990-1995. | a seroepidemiological survey was carried out during 1994 in the municipality of paracambi, state of rio de janeiro. haemagglutination inhibition test positivity was detected in 145 out of 370 (39.2%) schoolchildren. the frequency of positive test by sex was 53.8% (78/145) female and 46.2% (67/145) male. distribution by age showed the increasing of antibody positivity in older children. strains of dengue virus type 1 and dengue virus type 2 were isolated before (1990) showing the co-circulation o ... | 1997 | 9322424 |
| rapid characterization of genetic diversity among twelve dengue-2 virus isolates by single-strand conformation polymorphism analysis. | single-strand conformation polymorphism (sscp) analysis was used to characterize genetic polymorphisms among 12 isolates of dengue-2 virus, which were previously genetically characterized by rnase t1 oligonucleotide mapping and by sequencing the viral envelope (e) gene. specific cdna fragments from the dengue-2 isolates were amplified by the reverse transcriptase-polymerase chain reaction. the viral e, premembrane (prm), and nonstructural 5 (ns5) gene cdnas of 291 basepairs (bp), 291 bp, and 201 ... | 1997 | 9347956 |
| antibodies against dengue virus e protein peptide bind to human plasminogen and inhibit plasmin activity. | both mice and rabbits immunized with dengue virus e protein peptide spanning amino acids 100-119 (d4e) produced antibodies that reacted not only with the d4e peptide itself but also with human plasminogen, as shown by elisa and western blot. sera from dengue virus-hyperimmunized mice and dengue patients also contained antibodies against d4e and plasminogen. furthermore, such sera all contained plasmin inhibitory activity. using affinity-purified anti-d4e antibodies and free d4e peptide for compe ... | 1997 | 9353146 |
| analysis of a recombinant dengue-2 virus-dengue-3 virus hybrid envelope protein expressed in a secretory baculovirus system. | in a step towards a tetravalent dengue virus subunit vaccine which is economical to produce, highly immunogenic and stable, a hybrid dengue virus envelope (e) protein molecule has been constructed. it consists of 36 amino acids from the membrane protein, the n-terminal 288 amino acids of the dengue-2 virus e protein plus amino acids 289-424 of the dengue-3 virus e protein. it has been engineered for secretory expression by fusion to a mellitin secretory signal sequence and truncation of the hydr ... | 1997 | 9367357 |
| dengue virus infection of human t lymphocytes. | we have previously reported (kurane et al., arch. virol. 110, 91-101, 1990) that human t cell leukemia and lymphoma cell lines could be infected with dengue virus. in the present study we examined whether human t lymphocytes which are not leukemia or lymphoma cells can be infected with dengue virus. dengue virus-specific human cd4+ t cell clones, jk44 and jk49, and cd8+ t cell clones, cb2.8 and cb6.17, were infected with dengue-2 virus. dengue virus antigen-positive cells were detected in each o ... | 1997 | 9385407 |
| cotranslational membrane insertion of the serine proteinase precursor ns2b-ns3(pro) of dengue virus type 2 is required for efficient in vitro processing and is mediated through the hydrophobic regions of ns2b. | polyprotein processing of dengue virus type 2, a positive strand rna virus, is carried out by the host signal peptidase and a novel two-component viral proteinase of the serine proteinase family, ns2b/ns3(pro), in the endoplasmic reticulum. using an in vitro processing system, we examined the cis and trans cleavages of the 2b/3 and 4b/5 sites by ns2b/ns3(pro), respectively. lysates of bhk-21 cells coexpressing ns2b and ns3(pro) mediated trans cleavage of the 4b/5 site in vitro, and the protease ... | 1997 | 9388208 |
| affinity-purified dengue-2 virus envelope glycoprotein induces neutralizing antibodies and protective immunity in mice. | we constructed a recombinant baculovirus which produces a dengue (den)-2 virus envelope (e) protein containing a six-histidine (h6) tag in place of the last 100 amino acids at its c-terminus. the recombinant protein was purified from the supernatant of baculovirus-infected spodoptera frugiperda insect cell cultures to apparent homogeneity by cation-chelation chromatography (talon) in which the h6-tagged e-protein was eluted under non-denaturing conditions with 100 mm imidazole at ph 8.0. mice va ... | 1997 | 9413106 |
| mutagenesis of the ns3 protease of dengue virus type 2. | the flavivirus protease is composed of two viral proteins, ns2b and ns3. the amino-terminal portion of ns3 contains sequence and structural motifs characteristic of bacterial and cellular trypsin-like proteases. we have undertaken a mutational analysis of the region of ns3 which contains the catalytic serine, five putative substrate binding residues, and several residues that are highly conserved among flavivirus proteases and among all serine proteases. in all, 46 single-amino-acid substitution ... | 1998 | 9420267 |
| vertical transmission of dengue. | dengue, an important mosquito-borne flavivirus infection, is endemic in southeast asia. we describe two mothers who had acute dengue 4 and 8 days before the births of their infants. one mother had worsening of her proteinuric pregnancy-induced hypertension, liver dysfunction, and coagulopathy and required multiple transfusions of whole blood, platelets, and fresh frozen plasma. her male infant was ill at birth, developed respiratory distress and a large uncontrollable left intracerebral hemorrha ... | 1997 | 9431381 |
| conversion of dengue virus replicative form rna (rf) to replicative intermediate (ri) by nonstructural proteins ns-5 and ns-3. | dengue viruses infect more than 100 million people each year and cause serious clinical manifestations. it is important to understand the replication of these viruses so that therapeutic and/or prophylactic agents may be designed. dengue virus type 2 nonstructural proteins ns-5 and ns-3 were produced by in vitro transcription and translation of cloned genes. both proteins possessed rna-dependent rna polymerase activity as measured by their ability to convert purified replicative form (rf) rna to ... | 1998 | 9452298 |
| molecular evolution of dengue type 2 virus in thailand. | dengue is a mosquito-borne viral infection that in recent years has become a major international public health concern. dengue hemorrhagic fever (dhf), first recognized in southeast asia in the 1950s, is today a leading cause of childhood death in many countries. the pathogenesis of this illness is poorly understood, mainly because there are no laboratory or animal models of disease. we have studied the genetic relationships of dengue viruses of serotype 2, one of four antigenically distinct den ... | 1998 | 9452299 |
| global situation of dengue and dengue haemorrhagic fever, and its emergence in the americas. | about two-thirds of the world's population live in areas infested with dengue vectors, mainly aedes aegypti. all four dengue viruses are circulating, sometimes simultaneously, in most of these areas. it is estimated that up to 80 million persons become infected annually although marked underreporting results in the notification of much smaller figures. currently dengue is endemic in all continents except europe and epidemic dengue haemorrhagic fever (dhf) occurs in asia, the americas and some pa ... | 1997 | 9477544 |
| identification of a major determinant of mouse neurovirulence of dengue virus type 2 using stably cloned genomic-length cdna. | a genomic-length cdna clone corresponding to the rna of dengue virus type 2 (den-2) new guinea c strain (ngc) was constructed in a low copy number vector. the cloned cdna was stably propagated in escherichia coil and designated pdvws501. rna transcripts produced in vitro from the cdna using t7 rna polymerase yielded infectious virus (mon501) upon electroporation into bhk-21 cells. when compared with parental ngc virus, mon501 replicated to similar levels in aedes albopictus c6/36 cells and showe ... | 1998 | 9519821 |
| the replicative intermediate molecule of bovine viral diarrhoea virus contains multiple nascent strands. | the replication of bovine viral diarrhoea virus (bvdv) rna is considered to involve replicative intermediates (ri) and replicative forms (rf) of virus rna. these rna species were radiolabelled metabolically by 3h-uridine in bvdv-infected cells and separated by sucrose gradient centrifugation. rna in the fractions was then digested with rnase a in high salt (2 x ssc) and the rnase-resistance was determined. using the baltimore formula, this led to the calculation that the ri of bvdv contained 6-7 ... | 1998 | 9541623 |
| ultrastructural studies on the reproductive system of male aedes aegypti (diptera: culicidae) infected with dengue 2 virus. | dengue 2 virus was found by transmission electron microscopy to be present in the reproductive tissues of male aedes aegypti (l) 14 d after intrathoracic inoculation. dengue 2 particles were detected in the matrix, epithelial cells, and the peripheral fat body of the testes; secretory droplets of columnar cells of the accessory glands; and the epithelial and muscle cells of the seminal vesicles. however, none was found in the germ cells (i.e., spermatogonia, spermatocytes, spermatid, or spermato ... | 1998 | 9542348 |
| effect of size and geographic origin of aedes aegypti on oral infection with dengue-2 virus. | differences in larval habitats cause variation in the size of aedes aegypti (l.) adults. we suspected that such size variation was related to the ease with which the mosquitoes could be infected with dengue virus. using a rearing procedure that produced three distinct size classes of mosquitoes, we determined the percentage of mosquitoes that developed disseminated dengue-2 infection following oral feeding with a suspension containing 3.3 x 10(7) plaque-forming units/ml. mosquitoes were reared f ... | 1998 | 9546404 |
| predominance of hla-restricted cytotoxic t-lymphocyte responses to serotype-cross-reactive epitopes on nonstructural proteins following natural secondary dengue virus infection. | we examined the memory cytotoxic t-lymphocytic (ctl) responses of peripheral blood mononuclear cells (pbmc) obtained from patients in thailand 12 months after natural symptomatic secondary dengue virus infection. in all four patients analyzed, ctls were detected in bulk culture pbmc against nonstructural dengue virus proteins. numerous cd4+ and cd8+ ctl lines were generated from the bulk cultures of two patients, kpp94-037 and kpp94-024, which were specific for ns1.2a (ns1 and ns2a collectively) ... | 1998 | 9557687 |
| effect of sublethal dosages of malathion on the oral susceptibility of aedes aegypti to dengue-2 virus infection. | 1997 | 9561626 | |
| cardiac involvement in dengue haemorrhagic fever. | we studied 17 consecutive patients of dengue haemorrhagic fever/dengue shock syndrome (dhf/dss) to assess cardiac function by radionuclide ventriculography, echocardiography and electrocardiography (ecg) during the epidemic of dengue virus type-2 (den-2) in delhi, india (1996). case definitions laid down by the who were followed. fourteen patients were seropositive for dengue infection. in radionuclide ventriculography study, the mean left-ventricular ejection fraction was 41.69 (5.04% (range 33 ... | 1998 | 9579814 |
| evaluation of the protective efficacy of a recombinant dengue envelope b domain fusion protein against dengue 2 virus infection in mice. | a recombinant protein containing part of the dengue (den) 2 envelope protein was evaluated as a subunit immunogen for vaccination against den virus infection. a gene fragment encoding amino acids 298-400 (b domain) of the den-2 virus envelope was expressed as a fusion protein with the maltose binding protein (mbp) of escherichia coli. this recombinant, den-2(b)/mbp, was purified and analyzed for its antigenicity, immunogenicity, and ability to protect mice against lethal challenge. the recombina ... | 1998 | 9598457 |
| molecular and in vitro analysis of eight dengue type 2 viruses isolated from patients exhibiting different disease severities. | potential genetic determinants of dengue virulence were studied by sequencing the entire genomes of eight dengue 2 virus strains isolated from patients exhibiting different disease severities during an epidemic season in northeastern thailand in 1993. the isolates came from one dengue shock syndrome (thnh-7/93), three dengue hemorrhagic fever, and four dengue fever patients. phylogenetic analysis showed that the isolates belonged to the southeast asian genotype. the 3' noncoding regions showed d ... | 1998 | 9601513 |
| comparison of various methods of detection of different forms of dengue virus type 2 rna in cultured cells. | in this report, the sensitivity of various methods of detection of dengue virus type 2 (den-2) sense, antisense, replicative intermediate (ri) and replicative form (rf) rnas in infected mosquito aedes pseudoscutellaris ap-61 and mammalian baby hamster kidney bhk-21 cells is compared. licl precipitation was used for separation of viral rf rna from ri rna. our results show that reverse transcription-polymerase chain reaction (rt-pcr) followed by southern blot analysis and slot blot hybridisation o ... | 1997 | 9607089 |
| molecular and epidemiologic analysis of dengue virus isolates from somalia. | nucleotide sequence analysis was performed on 14 dengue virus isolates (13 dengue-2 viruses and 1 dengue-3 virus) recovered from febrile soldiers in somalia in 1993. the dengue-2 viruses were most closely related to dengue-2 virus recovered in somalia in 1984. however, differences in nucleotide sequence (0.35% to 1.35%) were evident among the 1993 isolates. these differences were closely associated with the geographic location of the infection as well as with different times of infection at the ... | 1998 | 9621203 |
| subcellular localization and some biochemical properties of the flavivirus kunjin nonstructural proteins ns2a and ns4a. | in a previous study on the replication of kunjin virus using immunoelectron microscopy (e. g. westaway, j. m. mackenzie, m. t. kenney, m. k. jones, and a. a. khromykh, 1997, j. virol. 71, 6650-6661), ns1 and ns3 were found associated with double-stranded rna (dsrna) within vesicle packets (vp) in infected vero cells, suggesting that these induced membrane structures may be the cytoplasmic sites of rna replication. ns2b and ns3 (comprising the virus-encoded protease) were colocalized within disti ... | 1998 | 9636360 |
| electron microscopic examination of aedes albopictus clone c6/36 cells infected with dengue virus 2 at elevated incubation temperature. | morphological changes such as loss of cytoplasm, membrane destruction and vacuolar swelling in aedes albopictus clone c6/36 cells infected with dengue virus 2 (dv-2) new guinea b strain and incubated at 28 degrees c and 37 degrees c, were observed under electron microscope. both infected and uninfected cells showed significant damage at 37 degrees c in contrast to normal appearance at 28 degrees c. a higher number of virus particles were observed in the cytoplasm at 37 degrees c than at 28 degre ... | 1998 | 9645241 |
| production of cytotoxic factor by peripheral blood mononuclear cells (pbmc) in patients with dengue haemorrhagic fever. | a unique cytokine, human cytotoxic factor (hcf), has been shown to occur in the sera of patients with dengue fever (df) and dengue haemorrhagic fever (dhf). the present study was undertaken to investigate the ability of fresh pbmc of such patients to produce hcf. the pbmc were cultured for 24 h and the culture supernatants (cs) were analysed for the presence of hcf by cytotoxicity assay, competitive elisa and dot blot tests. in 90% of 246 cases cs were positive for hcf by the three tests. cs wer ... | 1998 | 9649218 |
| monoclonal antibody mapping of the envelope glycoprotein of the dengue 2 virus, jamaica. | although dengue (den) virus is the etiologic agent of dengue fever, the most prevalent vector-borne viral disease in the world, precise information on the antigenic structure of the dengue virion is limited. we have prepared a set of murine monoclonal antibodies (mabs) specific for the envelope (e) glycoprotein of den 2 virus and used these antibodies in a comprehensive biological and biochemical analysis to identify 16 epitopes. following domain nomenclature developed for the related flavivirus ... | 1998 | 9657950 |
| dengue and dengue hemorrhagic fever. | dengue fever, a very old disease, has reemerged in the past 20 years with an expanded geographic distribution of both the viruses and the mosquito vectors, increased epidemic activity, the development of hyperendemicity (the cocirculation of multiple serotypes), and the emergence of dengue hemorrhagic fever in new geographic regions. in 1998 this mosquito-borne disease is the most important tropical infectious disease after malaria, with an estimated 100 million cases of dengue fever, 500,000 ca ... | 1998 | 9665979 |
| identification of specific nucleotide sequences within the conserved 3'-sl in the dengue type 2 virus genome required for replication. | the flavivirus genome is a positive-stranded approximately 11-kb rna including 5' and 3' noncoding regions (ncr) of approximately 100 and 400 to 600 nucleotides (nt), respectively. the 3' ncr contains adjacent, thermodynamically stable, conserved short and long stem-and-loop structures (the 3'-sl), formed by the 3'-terminal approximately 100 nt. the nucleotide sequences within the 3'-sl are not well conserved among species. we examined the requirement for the 3'-sl in the context of dengue virus ... | 1998 | 9696848 |
| [the specific epidemiological surveillance of dengue: the method and its importance since the dengue-2 epidemic in french polynesia in 1996]. | dengue fever is present in tropical and subtropical regions and its geographical extension and the simultaneous increase of its mortality are worrisome. in endemic or epidemic countries, the aim of dengue-specific epidemiological surveillance is to confirm as soon as possible the circulation of a new viral dengue serotype, i.e. the beginning of an epidemic. the efficiency of the control strategy is improved by an earlier epidemic alert. in french polynesia, dengue-3 virus circulated since 1989 a ... | 1998 | 9705191 |
| the 1993 dengue 2 epidemic in charters towers, north queensland: clinical features and public health impact. | in 1993 an epidemic caused by dengue virus type 2 occurred in several north queensland population centres. charters towers, estimated population 10,000, had 155 officially notified cases. an analysis of symptoms was undertaken using a random sample of 1000 residents to determine specificity of symptoms, the subclinical infection rate, and to establish the true extent of the epidemic. retrospective diagnoses of dengue fever were based on the presence of both serum dengue 2 neutralizing antibody a ... | 1998 | 9747766 |
| the 1993 dengue 2 epidemic in north queensland: a serosurvey and comparison of hemagglutination inhibition with an elisa. | an epidemic of dengue type 2 infection occurred in north queensland during 1992 and 1993. a random serosurvey of 1,000 residents of a population that experienced this epidemic only during 1993 was conducted to determine the proportion of the population at risk for secondary infection in the event of another epidemic with a different serotype. the ability of an elisa to detect prior exposure to the dengue virus was compared with the hemagglutination inhibition assay. dengue 2 virus plaque-reducti ... | 1998 | 9749644 |
| [direct sequencing of an amplified product from a serum sample]. | it is reported the nucleotide and amino acidic sequence of a great variability region in the dengue 2 virus genome, starting from the rna of the original virus with no passage in the isolation systems. it is compared with the first strain of dengue 2 isolated during the 1981 epidemic with 4 passages in lactating mouse. results show that the nucleotide sequence of serum and of strain a15 are the same. | 1996 | 9768271 |
| dengue encephalitis in french guiana. | thousands of cases of dengue fever (df) and several cases of dengue haemorrhagic fever were recorded in french guiana during the recent outbreak of dengue-2 virus (1991-1992) and in subsequent years. one case with clinical signs typical of classical df with neurological complications is reported in this study. the neurological features (encephalitis) appeared during the acute phase, 2 days after the onset of fever. dengue-2 virus was detected in both the cerebrospinal fluid and blood sample. thi ... | 1998 | 9783339 |
| [an immunoenzyme assay for the detection of monoclonal antibodies against the e and ns1 proteins of the dengue virus]. | the elisa was standardized to detect monoclonal antibodies of dengue virus proteins e and ns1. one indirect elisa was applied, using c6-36 cells inoculated with the a-15 strain, isolated during the dengue 2 epidemic in 1981 as an antigen source. these cells were fixed in elisa plates at a 200,000 cell/well concentration. a cell control in similar conditions was used. specific monoclonal antibodies to both proteins were used to standardize the system. studies at different incubation periods, to d ... | 1995 | 9805082 |
| illness in journalists and relief workers involved in international humanitarian assistance efforts in somalia, 1992-93. | background: journalists and relief workers participating in international relief efforts in somalia following the intervention of outside armed forces in late 1992, were faced with a number of threats to their health. principally these threats were from endemic infectious diseases and trauma. methods: in-patient, emergency clinic, and laboratory records of u.s. military field hospitals, which provided the only available sophisticated medical care in somalia during most of the study period (decem ... | 1995 | 9815365 |
| growth restriction of dengue virus type 2 by site-specific mutagenesis of virus-encoded glycoproteins. | the three flavivirus glycoproteins prm, e and ns1 are formed by post-translational cleavage and are glycosylated by the addition of n-linked glycans. ns1 may form homodimers, whereas e may form homodimers, homotrimers or heterodimers (prm-e). modification of these processes by mutagenesis of the proteins has the potential to generate viruses that are restricted in growth and are possible vaccine candidates. using an sv40-based expression system, we previously analysed dimerization and secretion ... | 1998 | 9820138 |
| analysis of antibody-independent binding of dengue viruses and dengue virus envelope protein to human myelomonocytic cells and b lymphocytes. | the identification of cell surface receptor molecules for the dengue viruses, one of the leading causes of morbidity and mortality in tropical and subtropical parts of the world, remains controversial. both glycoproteins and glycosaminoglycans have been identified as likely candidates on various cell types. however, most of these studies have used cell types other than those thought to be the main target cells in humans: monocyte-macrophages, b lymphocytes and bone marrow cells. in this report c ... | 1998 | 9833887 |
| determinants of dengue 2 infection among residents of charters towers, queensland, australia. | dengue fever is caused by one of the four serotypes of the dengue virus and is transmitted by the urban mosquito aedes aegypti. in 1993, the city of charters towers in the tropical north of australia experienced an epidemic caused by the dengue 2 virus. a cross-sectional sample of 1,000 people was assessed for determinants of recent symptomatic dengue infection. after exclusion of people with prior exposure to dengue 2, a study group of 797 persons, including 196 patients with recent infection, ... | 1998 | 9850134 |
| changing clinical and biological manifestations of dengue during the dengue-2 epidemic in french polynesia in 1996/97--description and analysis in a prospective study. | in august 1996 dengue-2 virus was detected in french polynesia for the first time since 1976. a prospective study was conducted from november 1996 to april 1997. each time one of 7 physicians suspected dengue, the patient was enrolled and epidemiological, clinical and biological data were recorded. dengue diagnosis was confirmed by virus isolation and igm detection. the aims of this study were to find clinical and biological predictive factors constituting a specific profile of dengue (df) and d ... | 1998 | 9855396 |
| quantitative genetics of vector competence for dengue-2 virus in aedes aegypti. | a quantitative genetic study of the ability of aedes aegypti to propagate dengue-2 (den-2) virus in the midgut and in a disseminated infection in the head was conducted with a standard half-sib breeding design. aedes aegypti aegypti and a. aegypti formosus differ markedly in oral susceptibility to den-2 virus. mosquitoes were orally infected and, after an extrinsic incubation period of 14 days, virus titer (by tissue culture infectious dose, 50% endpoint) was determined in the midgut (mt) and he ... | 1998 | 9886207 |
| antibody responses to an immunodominant nonstructural 1 synthetic peptide in patients with dengue fever and dengue hemorrhagic fever. | two flaviviruses, dengue (den) virus and japanese encephalitis (je) virus, are important because of their global distribution and the frequency of epidemics in tropical and subtropical areas. to study the b-cell epitopes of nonstructural 1 (ns1) glycoprotein and anti-ns1 antibody response in den infection, a series of 15-mer synthetic peptides from the predicted b-cell linear epitopes of den-2 ns1 protein were prepared. enzyme-linked immunosorbent assay (elisa) was performed to analyze antibody ... | 1999 | 9890415 |
| molecular epidemiology of malaysian dengue 2 viruses isolated over twenty-five years (1968-1993). | the limited sequencing approach was used to study the molecular epidemiology of 24 malaysian dengue 2 viruses which were isolated between 1968 and 1993. the sequences of a 240-nucleotide-long region across the envelope/non-structural 1 protein (e/ns1) gene junction of the isolates were determined and analysed. alignment and comparison of the nucleotide and deduced amino acid sequences of the isolates revealed that nucleotide changes occurred mostly at the third position of a particular codon and ... | 1998 | 9923022 |