Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| innate antiviral immunity in drosophila. | the study of drosophila, and other genetically tractable insects, has expanded our understanding of innate immunity and more recently antiviral innate mechanisms. the drosophila antiviral program includes inflammatory signaling cascades as well as antiviral rna silencing and autophagy. this review will highlight the recent discoveries in antiviral immunity in insects and will reveal some of the lessons learned. | 0 | 20137906 |
| rna interference-mediated antiviral defense in insects. | small interfering rna (sirna)-mediated rna interference (rnai) pathways are critical for the detection and inhibition of rna virus replication in insects. recent work has also implicated rnai pathways in the establishment of persistent virus infections and in the control of dna virus replication. accumulating evidence suggests that diverse double-stranded rnas produced by rna and dna viruses can trigger rnai responses yet many viruses have evolved mechanisms to inhibit rnai defenses. therefore, ... | 0 | 26034705 |
| transgene-mediated suppression of the rna interference pathway in aedes aegypti interferes with gene silencing and enhances sindbis virus and dengue virus type 2 replication. | rna interference (rnai) is the major innate antiviral pathway in aedes aegypti that responds to replicating arboviruses such as dengue virus (denv) and sindbis virus (sinv). on the one hand, the mosquito's rnai machinery is capable of completely eliminating denv2 from ae. aegypti. on the other, transient silencing of key genes of the rnai pathway increases replication of sinv and denv2, allowing the viruses to temporally overcome dose-dependent midgut infection and midgut escape barriers (meb) m ... | 0 | 23331493 |
| virus-derived sirnas and pirnas in immunity and pathogenesis. | cellular organisms have evolved related pathways for the biogenesis and function of small interfering rnas (sirnas), micrornas and piwi-interacting rnas (pirnas). these distinct classes of small rnas guide specific gene silencing at both transcriptional and posttranscriptional levels by serving as specificity determinants. small rnas of virus and host origins have been found to modulate virus–host interactions by rna interference (rnai), leading to antiviral immunity or viral pathogenesis. deep ... | 0 | 22180767 |
| genetic dissection of flaviviridae host factors through genome-scale crispr screens. | the flaviviridae are a family of viruses that cause severe human diseases. for example, dengue virus (denv) is a rapidly emerging pathogen causing an estimated 100 million symptomatic infections annually worldwide. no approved antivirals are available to date and clinical trials with a tetravalent dengue vaccine showed disappointingly low protection rates. hepatitis c virus (hcv) also remains a major medical problem, with 160 million chronically infected patients worldwide and only expensive tre ... | 0 | 27383987 |
| viruses and autophagy. | autophagy is an evolutionarily conserved intracellular process by which bulk cytoplasm is enveloped inside a double-membraned vesicle and shuttled to lysosomes for degradation. within the last 15 years, the genes necessary for the execution of autophagy have been identified and the number of tools for studying this process has grown. autophagy is essential for tissue homeostasis and development and defective autophagy is associated with a number of diseases. as intracellular parasites, during th ... | 0 | 19750559 |
| new approaches for the standardization and validation of a real-time qpcr assay using taqman probes for quantification of yellow fever virus on clinical samples with high quality parameters. | the development and production of viral vaccines, in general, involve several steps that need the monitoring of viral load throughout the entire process. applying a 2-step quantitative reverse transcription real time pcr assay (rt-qpcr), viral load can be measured and monitored in a few hours. in this context, the development, standardization and validation of a rt-qpcr test to quickly and efficiently quantify yellow fever virus (yfv) in all stages of vaccine production are extremely important. ... | 0 | 26011746 |
| highly divergent dengue virus type 2 in traveler returning from borneo to australia. | dengue virus type 2 was isolated from a tourist who returned from borneo to australia. phylogenetic analysis identified this virus as highly divergent and occupying a basal phylogenetic position relative to all known human and sylvatic dengue virus type 2 strains and the most divergent lineage not assigned to a new serotype. | 0 | 27869598 |
| rna methyltransferases involved in 5' cap biosynthesis. | in eukaryotes and viruses that infect them, the 5' end of mrna molecules, and also many other functionally important rnas, are modified to form a so-called cap structure that is important for interactions of these rnas with many nuclear and cytoplasmic proteins. the rna cap has multiple roles in gene expression, including enhancement of rna stability, splicing, nucleocytoplasmic transport, and translation initiation. apart from guanosine addition to the 5' end in the most typical cap structure c ... | 0 | 25626080 |
| reply to skalsky et al.: a microrna-like small rna from dengue virus. | 0 | 25061641 | |
| multicomponent, mannich-type assembly process for generating novel, biologically-active 2-arylpiperidines and derivatives. | a multicomponent, mannich-type assembly process commencing with commercially available bromobenzaldehydes was sequenced with [3+2] dipolar cycloaddition reactions involving nitrones and azomethine ylides to generate collections of fused, bicyclic scaffolds based on the 2-arylpiperidine subunit. use of the 4-pentenoyl group, which served both as an activator in the mannich-type reaction and a readily-cleaved amine protecting group, allowed sub-libraries to be prepared through piperidine n-functio ... | 0 | 25267860 |
| co-circulation of dengue and chikungunya viruses, al hudaydah, yemen, 2012. | we investigated 400 cases of dengue-like illness in persons hospitalized during an outbreak in al hudaydah, yemen, in 2012. overall, 116 dengue and 49 chikungunya cases were diagnosed. dengue virus type 2 was the predominant serotype. the co-circulation of these viruses indicates that mosquitoborne infections represent a public health threat in yemen. | 0 | 25061762 |
| evaluation of a monoclonal antibody-based rapid immunochromatographic test for direct detection of rabies virus in the brain of humans and animals. | rabies diagnosis uses a direct fluorescent antibody test (fat) that is difficult, costly, and time-consuming, and requires trained personnel. we developed a rapid immunochromatographic test (rict) for the diagnosis of rabies. the efficacy of the rict was compared with that of the fat. brain samples were collected from humans, dogs, cats, and other animals in sri lanka (n = 248), bhutan (n = 27), and thailand (n = 228). the sensitivity (0.74-0.95), specificity (0.98-1.0), positive predictive valu ... | 0 | 22492163 |
| activatable optical probes for the detection of enzymes. | the early detection of many human diseases is crucial if they are to be treated successfully. therefore, the development of imaging techniques that can facilitate early detection of disease is of high importance. changes in the levels of enzyme expression are known to occur in many diseases, making their accurate detection at low concentrations an area of considerable active research. activatable fluorescent probes show immense promise in this area. if properly designed they should exhibit no si ... | 0 | 23519774 |
| cytoplasmic viral replication complexes. | many viruses that replicate in the cytoplasm compartmentalize their genome replication and transcription in organelle-like structures that enhance replication efficiency and protection from host defenses. in particular, recent studies with diverse positive-strand rna viruses have further elucidated the ultrastructure of membrane-bound rna replication complexes and how these complexes function in close coordination with virion assembly and budding. the structure, function, and assembly of some po ... | 0 | 20638644 |
| regulation of immunogen processing: signal sequences and their application for the new generation of dna-vaccines. | immunization with naked genes (dna-immunization) is a perspective modern approach to prophylactic as well as therapeutic vaccination against pathogens, as well as cancer and allergy. a panel of dna immunogens has been developed, some are already in the clinical trials. however, the immunogenicity of dna vaccines, specifically of those applied to humans, needs a considerable improvement. there are several approaches to increase dna vaccine immunogenicity. one approach implies the modifications of ... | 0 | 22649628 |
| vertical transmission of dengue virus in aedes aegypti collected in puerto iguazú, misiones, argentina. | a finding of vertical transmission of the den 3 virus in male specimens of aedes aegypti, collected in the 2009 fall-winter period, in puerto iguazú city, misiones, argentina, using the rt-pcr technique in a 15-specimen pool is reported. this result is analyzed within the context of the epidemiological situation of argentina's northeast border. | 0 | 24626420 |
| serologic evidence of flavivirus infection in bats in the yucatan peninsula of mexico. | we captured 140 bats of seven species in merida city in the yucatan peninsula of mexico in 2010. serum was collected from each bat and assayed by plaque reduction neutralization test (prnt) using six flaviviruses: west nile virus, st. louis encephalitis virus, and dengue viruses 1-4. flavivirus-specific antibodies were detected in 26 bats (19%). the antibody-positive bats belonged to three species: the pallas's long-tongued bat (glossophaga soricina), jamaican fruit bat (artibeus jamaicensis), a ... | 0 | 23778622 |
| emergence of dengue in tribal villages of mandla district, madhya pradesh, india. | dengue (den) is a rapidly spreading arboviral disease transmitted by aedes mosquitoes. although it is endemic in india, dengue virus (denv) infection has not been reported from tribal areas of madhya pradesh. investigations were conducted to establish the aetiology of sudden upsurge of cases with febrile illness in june 2013 from tribal villages of mandla district of madhya pradesh, india. | 0 | 26139775 |
| rock is involved in vimentin phosphorylation and rearrangement induced by dengue virus. | our previous study showed that dengue virus 2 (denv2) infection induces rearrangement of vimentin into dense structures at the perinuclear area. however, the underlying mechanism of this phenomenon is poorly characterized. in the present work, we found that vimentin and ser71 phosphorylated vimentin display similar distributions in denv2-infected cells. denv2 infection also induced rock activation and phosphorylation of vimentin at ser71 as the denv2 infection progressed. furthermore, ser71 phos ... | 0 | 23737341 |
| dengue virus. cryo-em structure of an antibody that neutralizes dengue virus type 2 by locking e protein dimers. | there are four closely-related dengue virus (denv) serotypes. infection with one serotype generates antibodies that may cross-react and enhance infection with other serotypes in a secondary infection. we demonstrated that denv serotype 2 (denv2)-specific human monoclonal antibody (hmab) 2d22 is therapeutic in a mouse model of antibody-enhanced severe dengue disease. we determined the cryo-electron microscopy (cryo-em) structures of hmab 2d22 complexed with two different denv2 strains. hmab 2d22 ... | 0 | 26138979 |
| physical and biological properties of dengue-2 virus and associated antigens. | dengue virus suspensions from mouse brain and cell culture were fractionated into three components by rate zonal centrifugation in sucrose gradients. infectious virus sedimented in a single zone and possessed hemagglutinating (ha) and complement fixing (cf) activity. electron micrographs showed the virion to be a spherical particle 48 to 50 nm in diameter with 7-nm spherical structures on its surface. buoyant density in cscl of virions from mouse brain was estimated at 1.22 g/cm(3) and from cell ... | 1970 | 4195055 |
| dengue virus plaque development in simian cell systems. i. factors influencing virus adsorption and variables in the agar overlay medium. | chemical and physical variables influencing the plaquing of all dengue serotypes in two simian cell systems were studied. calf serum in the nutrient overlay may be replaced by mouse ascitic fluid or bovine plasma albumin when employing the rhesus monkey kidney llc-mk(2) cell system for plaquing all dengue serotypes. doubling the serum concentration in the overlay had little effect in modifying dengue types 1, 2, 3, and 4 plaque titers. newborn agamma, 4-week-old and 8-week-old calf serum gave co ... | 1970 | 4987200 |
| dengue virions and antigens in brain and serum of infected mice. | the temporal relationships of the production of infectious dengue-2 virus and its antigens were investigated in intracerebrally infected suckling mice. infectious virus, a slowly sedimenting noninfectious hemagglutinin (sha), and a noninfectious soluble complement-fixing antigen (scf) were found in the brain. serum contained high concentrations of scf antigen relative to infectivity when compared to scf to infectivity ratios in the brain. degradation of virions by tween-80 and ether produced two ... | 1970 | 5497897 |
| comparison of three methods used to isolate dengue virus type 2. | during the 1969 dengue epidemic in puerto rico, human sera and aedes aegypti mosquitoes were collected for virus isolation and identification. three methods of isolation were used and compared. in the first method, we inoculated newborn mice by the intracranial route, noted any signs of illness, and serially passed specimens in mice until virus was isolated. in the second method, we inoculated tube cultures of llc-mk(2) cells, noted any cytopathic effect (cpe), and assayed fluids for virus by pl ... | 1971 | 5002896 |
| the mechanism of cross-protection afforded by dengue virus against west nile virus in hamsters. | the protection afforded by similar concentrations of different dengue virus serotypes against a subsequent challenge of west nile virus was studied in hamsters. the new guinea c strain of dengue 2 virus gave the best protection. it was found that the anamnestic neutralizing antibody response induced by the challenge west nile virus against west nile virus in hamsters, previously immunized with dengue 2 virus, might play a major role in the cross-protection observed in this system. | 1972 | 4509639 |
| rapid complement fixation technique for estimating complement-fixing antigen elution profiles of viruses from gel filtration columns. | the complement fixation elution profiles of dengue-2 virus-infected suckling mouse brain supernatant fluids from sephadex g-200 columns were compared by the antigen end-point titration procedure and by a complement dilution technique. the latter technique was found to be a quick method for approximating the complement-fixing antigen in eluates. | 1972 | 5057370 |
| host-induced modification of dengue-2 virus surface antigens in aedes albopictus cells. | 1973 | 4132537 | |
| sequential immunization procedure against group b arboviruses using living attenuated 17d yellow fever virus, living attenuated langat e5 virus, and living attenuated dengue 2 virus (new guinea c isolate). | 1973 | 4352231 | |
| cloning of dengue virus type 2 by the direct fluorescent antibody technique. | 1973 | 4589217 | |
| dengue virus infection of mice: morphology and morphogenesis of dengue type-2 virus in suckling mouse neurones. | in dengue type-2 virus-infected neurones of suckling mice, formation of single-membrane vesicles is observed in the distended cisternae of the endoplasmic reticulum mostly of the perinuclear zone around 72 h after inoculation. electron-dense 50-nm virus particles are arranged in chains in these distended cisternae; some form small crystalloid aggregates. aberrant particles of different shapes are also seen in the distended cisternae about the same time that the virus particles appear. parallel f ... | 1973 | 4594115 |
| the attenuation of the 26th mouse brain passage of new guinea c strain of dengue 2 virus for use in the sequential immunization procedure against group b arboviruses. | 1973 | 4630883 | |
| recovery of dengue-2 virus from aedes aegypti in colombia. | 1973 | 4745238 | |
| replication of dengue virus type 2 in aedes albopictus cell culture. | the replication of type 2 dengue (d-2) virus in aedes albopictus (aal) mosquito cell cultures differed from that in vertebrate (llc-mk2) rhesus monkey kidney cells. virus readily replicated in aal cells at either 30 or 37 c, but had no apparent effect on the host cell. persistent infection was established with continual virus production for at least 6 months, although the virulence of progeny virus for both suckling mice and llc-mk2 cells became attenuated. density gradient analysis of infected ... | 1973 | 4201188 |
| morphology and development of dengue-2 virus employing the freeze-fracture and thin-section techniques. | 1974 | 4591567 | |
| proceedings: cytopathic effect of dengue-2 virus on an established mosquito cell-line. | 1974 | 4818653 | |
| seroepidemiologic study of arbovirus infections in the north-east and south of thailand. | blood specimens were collected from villagers in khon-kaen province, in the north-eastern region, and in songkhla province, in the southern region of thailand in the pre- and post-epidemic seasons of hemorrhagic fever. the hemagglutination inhibition antibody titers of the specimens were measured against dengue virus type 2, type 4, japanese encephalitis virus and chikungunya virus. in general, khon-kaen villagers showed higher levels of hi antibodies against these arboviruses than songkhla vill ... | 1974 | 4464834 |
| placental passage of antibodies to dengue virus in persons living in a region of hyperendemic dengue virus infection. | maternal and umbilical cord levels of antibodies to dengue 2 and 3 viruses were compared in 54 matched pairs of specimens from subjects in the dominican republic. dengue infection appeared to be hyperendemic; pregnant women experienced a 6% weekly infection rate. titers of antibody to dengue 2 and 3 viruses were considerably higher in cord sera than in maternal sera (p smaller than 0.001 and p smaller 0.01, respectively), especially when maternal levels were low. when maternal and cord sera were ... | 1975 | 805190 |
| the influence of arboviral infection on the susceptibility of cultured cells to immune injury in vitro. | the susceptibility of llc-mk2 monkey kidney cells to antivirus (antibodies versus viral antigens in the plasma membrane) and anticell (antibodies versus plasma membrane antigens) immune cytolysis in vitro was observed during the course of 100 continuous subcultures of these cells. in that period, llc-mk2 cells infected with the group b arboviruses, japanese encephalitis virus and dengue 2 virus, became progressively refractory to the complement-dependent antivirus immune cytolysis as measured ... | 1975 | 808137 |
| influence of cell type and virus upon virus-specific immune cytolysis. | immune cytolysis was measured by release of absorbed radioactive chromium from infected cells that were incubated with antiviral antibody and complement. the presence of virus-specific antigens detected in this manner on the surface of several types of cells infected with japanese encephalitis (je) virus did not correlate in each instance with the maturation of infectious virus. je-infected llc-mk-2 and vero cells could not be lysed until long after the first appearance of released virus, and th ... | 1975 | 803470 |
| chemically induced temperature-sensitive mutants of dengue virus type 2: comparison of temperature sensitivity in vitro with infectivity suckling mice, hamsters, and rhesus monkeys. | a series of temperature-sensitive (ts) mutants of dengue virus type 2 (den-2, th-36 isolate) were induced by treatment with 5-azacytidine. these mutants and parental viruses were compared for the ts trait and/or attenuation in four systems: primary hamster kidney cells, suckling mice, golden syrian hamsters, and rhesus monkeys. seven clones judged to possess the ts trait in virto demonstrated a variety of patterns in vivo. on initial isolation, five of seven ts mutants exhibited reduced mouse le ... | 1976 | 57925 |
| isolation of a temperature-sensitive dengue-2 virus under conditions suitable for vaccine development. | dengue virus, type 2, in viremic human sera and after passage in cell cultures produces mixtures of small and large plaques when assayed in llc-mk2 cells. clones of dengue virus type 2 obtained by plaque selection in primary green monkey kidney cell cultures were tested for temperature sensitivity in vitro and for virulence by intracerebral inoculation of suckling mice. sublines of a small-plaque clone were found to have lower nonpermissive temperatures than the parent virus by both plaque forma ... | 1976 | 977127 |
| endemic dengue virus infection in hispaniola. i. haiti. | antibodies to group b arbovirus were common among coastal populations in the haitian part of the caribbean island of hispaniola. antibodies were present in 43% of children one to five years old; prevalence in older persons increased with age. in nine asymptomatic persons serodiagnostic changes indicative of group b arbovirus were detected during six of twelve consecutive months. in port cities where antibodies were common in children, aedes aegypti indices of 50%-70% were observed; in contrast, ... | 1976 | 993618 |
| variation among geographic strains of aedes albopictus in susceptibility to infection with dengue viruses. | the comparative susceptibility to dengue virus infection of 13 geographic strains of aedes albopictus was studied by feeding the mosquitoes on a virus-erythrocyte-sugar suspension. significant variation in susceptibility for each of the four dengue serotypes was observed among the geographic strains. mosquito strains which were more susceptible to infection with one dengue serotype also were more susceptible to the other dengue serotypes. there was a direct relationship between the amount of vir ... | 1976 | 1259091 |
| chemically-induced temperature sensitive mutants of dengue virus type 2. i. isolation and partial characterization. | temperature sensitive (ts) mutants of dengue virus type 2 (den-2, th-36 isolate) were induced by replication in primary hamster kidney cells treated with 5-azacytidine. seven ts mutants were obtained from 138 clones isolated by an immunofluorescent cloning technique. of these 7 ts mutants, 5 were sufficiently stable to permit partial characterization. complementation was detected at very low but statistically significant levels between some ts mutants at 40 degrees c. viral double-stranded rna p ... | 1976 | 56929 |
| dengue virus replication enhancement in peripheral blood leukocytes from immune human beings. | dengue 2 virus replication in peripheral blood leukocyte cultures from 10 of 13 asian or polynesian subjects with actively acquired dengue immunity and two of three infants with passively acquired dengue antibody. only 2 of 11 cultures from nonimmune infants or children supported viral replication. this study establishes a parallel in the biological behavior of human and simian pbl with respect to the immunological dependence of dengue virus replication in vitro. elucidation of the mechanism (or ... | 1976 | 1250839 |
| replication of dengue-2 virus in cultured human lymphoblastoid cells and subpopulations of human peripheral leukocytes. | we studied the susceptibility of four human lymphoblastoid cell lines (hcl) and of subpopulations of circulating peripheral human leukocytes to dengue-2 virus infection. hcl with b cell characteristics (raji, wil 2wt, 8866), b-type peripheral lymphocytes, and macrophages were productively infected by dengue-2 virus. in contrast, an hcl with t cell characteristics (molt-4), t type peripheral lymphocytes, and polymorphonuclear (pmn) cells did not become infected and replicate dengue-2 virus. pmn c ... | 1976 | 1085314 |
| virulence and immunogenicity of a temperature-sensitive dengue-2 virus in lower primates. | clones of dengue-2 virus were tested for virulence by inoculation of rhesus monkeys and chimpanzees. although primates showed no overt signs of illness, inoculation with the parent virus or a subline of a large-plaque clone resulted in a viremia lasting 1 to 7 days. by these criteria, sublines of a small-plaque clone were significantly less virulent and produced little or no viremia in primate hosts. although they had a substantially reduced viremia, primates inoculated with the small-plaque sub ... | 1977 | 409682 |
| replication of dengue-2 virus in aedes albopictus mosquitoes. an electron microscopic study. | sequential electronmicroscopic studies of aedes albopictus mosquitoes infected with dengue-2 virus showed replication of virus particles and vesicular structures confined to cells having an active, rough, endoplasmic reticulum. small granules not found on the surface of virions produced in mammalian cells were seen on the envelopes of the virus particles. there was no evidence of nuclear involvement as described in infected mouse neurones, and there was no apparent impairment of cellular functio ... | 1977 | 596516 |
| dengue viruses and mononuclear phagocytes. ii. identity of blood and tissue leukocytes supporting in vitro infection. | studies were made on the identity of human and monkey mononuclear leukocytes permissive to antibody-enhanced dengue 2 virus (d2v) infection. in cultures of peripheral blood leukocytes (pbl) inoculated immediately after separation, it was concluded that only mononuclear phagocytes support dengue infection. this is based upon observations that d2v-permissive cells were resistant to 1,200 rads, were both plastic adherent and nonadherent, were removed when passed through nylon wool columns in 10 per ... | 1977 | 195000 |
| dengue viruses and mononuclear phagocytes. i. infection enhancement by non-neutralizing antibody. | cultured mononuclear peripheral blood leukocytes (pbl) from nonimmune human beings and monkeys are nonpermissive to dengue 2 virus (d2v) infection at multiplicities of infection of 0.001-0.1, but become permissive when non-neutralizing dengue antibody is added to medium. d2v infection occurred in pbl prepared from anti-coagulated but not from defibrinated plasma. infection enhancement was produced by multiple lots of heterotypic anti-dengue raised in several mammalian species. homotypic anti-den ... | 1977 | 406347 |
| cultivation of dengue virus type 2 in candidate substrates for vaccine production. | 1978 | 415061 | |
| ultrastructural studies on dengue virus infection of human lymphoblasts. | ultrastructural studies of dengue-2 virus-infected lymphoblastoid raji cells showed that the virus induced an increase in the size of the rough endoplasmic reticula (rer) and that the replication of the virus was confined to the cisternae of these rer. the proliferating rer formed cytoplasmic inclusions that could be seen by light microscopy. this observation could be used as evidence of a cytopathogenic effect of dengue virus on infected rajii cells in routine cultures. accumulation of virions ... | 1978 | 669791 |
| arthropod-borne virus infections in western new guinea (irian jaya): a serological retrospection. | a serological investigation, covering many localities throughout western new guinea (irian jaya) in 1958-1961 showed that: a general endemicity of arbovirus infections rather than sporadic epidemics, exists in the southern lowlands--large differences exist in geographical distribution of these viruses especially when comparing coastal areas of the southern, with those of the northern and north western parts of the island--in both arbovirus groups noticeable differences in altitude were observed ... | 1978 | 749276 |
| studies on the susceptibility of a large urban population of aedes aegypti to infection with dengue viruses. | a large urban population of aedes aegypti in jakarta, indonesia was studied for one year to determine whether it was homogeneous in terms of susceptibility to dengue viruses and whether seasonal changes in susceptibility to dengue viruses occurred. mosquitoes from several districts in jakarta showed a low but homogeneous susceptibility to dengue 2 virus from november 1975 to april 1976. in june 1976, increased susceptibility to dengue 2 virus was observed among some of the subpopulations of ae. ... | 1978 | 751215 |
| phytohemagglutinin enhancement of dengue-2 virus replication in nonimmune rhesus monkey peripheral blood leukocytes. | phytohemagglutinin treatment of peripheral blood leukocytes from dengue nonimmune monkeys enhanced dengue-2 virus replication. enhancement was due primarily to an increase in the number of infected cells. destruction of mononuclear phagocytes with silica did not significantly inhibit virus replication in phytohemagglutinin-treated cultures. pokeweed mitogen, concanavalin a, and streptolysin o stimulated increased deoxyribonucleic acid synthesis in monkey leukocytes but did not enhance virus repl ... | 1978 | 203535 |
| replication of dengue and junin viruses in cultured rabbit and human endothelial cells. | the flavivirus dengue and the arenavirus junin are both associated with a hemorrhagic shock syndrome in man. we have demonstrated the replication of these viruses in vitro in both rabbit and human endothelial cells by viral titers and immunofluorescent antibody studies. rabbit endothelium established in continuous culture was derived from vena cava, while human cells in primary culture were derived from umbilical veins. in rabbit endothelium, dengue-2 virus passaged through monkey kidney monolay ... | 1978 | 208980 |
| fluorescent antibody studies on the development of dengue-2 virus in aedes albopictus (diptera: culicidae). | 1979 | 396372 | |
| effect of passage history on dengue-2 virus replication in subpopulations of human leukocytes. | three passage levels of dengue-2 virus strain pr-159, obtained during the course of deriving the attenuated s-1 vaccine, were tested for their ability to replicate in subpopulations of human peripheral blood leukocytes: (i) 6th primary african green monkey kidney (pgmk) cell passage (parent virus); (ii) 19th pgmk cell passage of a small-plaque-forming clone derived from the parent virus (s-1 pgmk virus); and (iii) virus derived by four additional passages of the s-1 pgmk virus in diploid fetal r ... | 1979 | 121109 |
| effect of immune status on dengue 2 virus replication in cultured leukocytes from infants and children. | cord blood leukocytes from neonates with maternal dengue antibody supported dengue 2 virus replication in vitro; those from neonates without maternal antibody did not. cord bloods of infants born to dengue-immune mothers contained a potent enhancing factor which gradually decayed with age and which was absent from neonates born to nonimmune mothers. permissiveness of cultures of washed peripheral blood leukocytes from infants with maternal antibody declined steadily with increasing age in parall ... | 1979 | 572345 |
| cultivation of dengue virus type 2 in baby hamster kidney cells in serum-free medium. | propagation of dengue virus type 2 (new guinea c strain) was performed using a shaker culture of baby hamster kidney cells (bhk-21) cultivated in serum-free modified waymouth medium. maximum virus titer varied from 10(8.3) to 10(8.8) plaque forming units/ml after incubation of bhk-21 cells in suspension culture at 37 dgrees c for 40-48 hours post-infection. | 1979 | 484777 |
| variation in susceptibility to oral infection with dengue viruses among geographic strains of aedes aegypti. | the comparative susceptibility of 13 geographic strains of aedes aegypti to oral infection with dengue viruses was studied by feeding the mosquitoes on a virus-erythrocyte-sugar suspension. significant variation in susceptibility to four dengue serotypes was observed among the geographic strains tested. mosquito strains which were more susceptible to one serotype were also more susceptible to the other serotypes, suggesting that the factors controlling susceptibility were the same for all types. ... | 1979 | 507282 |
| absence of leukocytes permissive to dengue 2 virus in the acute phase of dengue hemorrhagic fever. | patients with primary dengue infection developed dengue 2 virus (d2v) permissive peripheral blood leukocytes (pbl) 2--3 weeks after infection. pbl from healthy individuals with dengue antibody were permissive to d2v in vitro, suggesting that immunologically mediated in vitro d2v permissiveness persists for a relatively long time after recovery from dengue infection. however, pbl obtained from second infection dengue hemorrhagic fever patients did not support d2v growth during the acute phase of ... | 1979 | 453450 |
| 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 ... | 1980 | 6157332 |
| inhibition of dengue virus replication by amantadine hydrochloride. | the effect of amantadine hydrochloride (1-adamantanamine hydrochloride) on dengue virus replication was examined in vitro. amantadine decreased the titers of all four types of dengue viruses grown in llc-mk2 cells by greater than 90% at concentrations of 50 micrograms/ml. there was no evidence for any cytopathic effect of the drug at concentrations less than 100 micrograms/ml. studies of the time of addition showed that the antiviral effect was maximal when drug was added to virus cultures immed ... | 1980 | 7416739 |
| studies on dengue 2 virus infection in cyclophosphamide-treated rhesus monkeys. | dengue 2 virus (d2v) replication has been demonstrated in cultured primate mononuclear phagocytes, mitogen treated lymphocytes and lymphoblastoid cells. to determine which of these cell types might play an important role in sustaining infection in vivo, nine rhesus monkeys were immunosuppressed with cyclophosphamide and then infected with d2v. maintenance dose which held total white blood cell counts to less than 3000/mm3 ablated both primary and secondary antibody responses. six successfully im ... | 1980 | 6770237 |
| dengue in the seychelles. | epidemics of dengue-like illness occurred in the seychelles from december 1976 to april 1977 and from december 1978 to january 1979. dengue 2 virus was isolated from individuals who had been in the seychelles in 1977. from february to april 1979, sera were collected from outpatients in mahé, seychelles, who had not previously been hospitalized with a dengue-like illness. results of neutralization tests with these sera indicated that prevalence rates for the four dengue viruses were between 81% a ... | 1981 | 6976229 |
| dengue-2 vaccine: virological, immunological, and clinical responses of six yellow fever-immune recipients. | six male volunteers, previously immunized with yellow fever vaccine, were inoculated subcutaneously with a live, attenuated dengue-2 virus (pr-159/s-1) candidate vaccine. five recipients developed viremia 8 or 9 days after vaccination, which lasted 1 to 10 days. the onset of viremia was followed by fever in three people, transient leukopenia in four, and an erythematous rash in one. one volunteer developed an oral temperature of 38.8 degrees c with headache, myalgia, fatigue, and photophobia sug ... | 1981 | 7216469 |
| infection of young adult mice with dengue virus type 2. | young adult female mice, five to six weeks old, were injected intraperitoneally with 2.5 x 10(6.3) ld50 of dengue-2 virus, new guinea c strain. the mice were killed on day 1, 2, 3, 4, 5, 6, 7, 10, 14, 21, 28, and 35 respectively. by means of the immunofluorescent antibody technique, viral antigen appeared as irregular granules in the reticuloendothelial cells of liver, lymph nodes and spleen of infected mice on the first day after inoculation and then diminished. from the fifth to sixth day of i ... | 1981 | 7036427 |
| suppression of dengue virus replication in vitro by rimantadine hydrochloride. | the effects of rimantadine on dengue virus replication were examined in a variety of tissue culture systems. the growth of dengue virus type 2 in human peripheral blood leukocytes (pbl) was completely suppressed when rimantadine was included in the culture medium at a concentration of 25 microgram/ml. similarly, rimantadine caused a significant inhibition of dengue virus replicaton in cultures of rhesus monkey pbl. addition of drug into virus-infected llc-mk2 cell cultures caused a decrease in t ... | 1981 | 7212165 |
| in vitro virulence marker: growth of dengue-2 virus in human leukocyte suspension cultures. | we wished to find a simple, biologically relevant method to evaluate the virulence of dengue viruses for human beings. since cells of mononuclear phagocyte lineage may be important sites of dengue infection in primates, we evaluated the permissiveness of these cells to dengue virus as a correlate of virus virulence. two wild-type, large-plaque, monkey-virulent dengue-2 virus strains and two small-plaque, monkey-avirulent dengue-2 virus strains were evaluated for their ability to replicate in hum ... | 1981 | 7216440 |
| depressed macrophage functions in dengue virus-infected mice: role of the cytotoxic factor. | dengue virus type 2 (dv) infection causes immunosuppression in mice. since macrophages are crucial for immune response, we have studied their functions in this condition and report our findings here. it was observed that in dv-infected mice the phagocytosis of neutral-red and latex particles by splenic and peritoneal-cavity macrophages was significantly reduced (p less than 0.001) from days 3 to 10 after inoculation. similarly the migration of splenic and peritoneal macrophages on a glass surfac ... | 1982 | 7073959 |
| identification of distinct antigenic determinants on dengue-2 virus using monoclonal antibodies. | monoclonal antibodies directed against antigenic determinants of the new guinea c strain of dengue-2 virus were obtained from lymphocyte hybridomas produced by fusing immune mouse lymphocytes with mouse myeloma cells. hybridoma cell culture supernatants were screened by using a radioimmunoassay employing detergent-solubilized dengue-2 infected cell antigens. monoclonal antibodies in ascitic fluids induced by 22 selected hybridomas were characterized by the hemagglutination-inhibition, plaque red ... | 1982 | 6177259 |
| dengue virus multiplication in cultures of mouse peritoneal macrophages: effects of macrophage activators. | dengue-2 virus multiplied in cultures of methylcellulose-induced peritoneal macrophages of balb/c mice. the in vitro-cultivated macrophages from dengue-1 virus-immune mice produced larger amounts of dengue-2 virus than did those from nonimmune controls. the effect of macrophage activators was examined by using nonimmune macrophages. enhanced virus production was demonstrated in cultures of macrophagges pretreated with phytohemagglutinin (pha) or bacterial lipopolysaccharide (lps). the number of ... | 1982 | 7176969 |
| dengue-2 virus in kenya. | 1982 | 6123900 | |
| enhancement of dengue virus type 2 replication in mouse macrophage cultures by bacterial cell walls, peptidoglycans, and a polymer of peptidoglycan subunits. | the effects of bacterial cell walls, peptidoglycans, and a water-soluble polymer of peptidoglycan subunits on dengue virus type 2 replication in cultured mouse peritoneal macrophages were studied. pretreatment of macrophage cultures with all of test cell walls isolated from seven bacterial species for 3 days significantly enhanced the virus production in the cultures. peptidoglycans prepared from four of the above cell walls also exerted the virus production-enhancing effects in a similar manner ... | 1983 | 6874066 |
| comparison of p388d1 mouse macrophage cell line and human monocytes for assay of dengue-2 infection-enhancing antibodies. | tissue culture-adapted dengue 2 virus (den 2), strain 16681, exhibits antibody-dependent enhancement of infection (ade) in p388d1 cells, a mouse macrophage-like cell line. ade is dependent upon maintaining den 2 multiplicity of infection at between 0.1 and 0.001, and can be simply measured in multi-well plastic plates. the assay uses either trypsinized or non-trypsinized p388d1 cells at 5 x 10(5) cells per ml, an appropriate dilution of den 2 virus, and a source of antibody, and is most convenie ... | 1983 | 6824121 |
| effect of dengue virus infection on fc-receptor functions of mouse macrophages. | fc-receptor-mediated attachment and ingestion of opsonized sheep erythrocytes (ea) by the macrophages of spleen and peritoneal cavity were studied during dengue virus type 2 (dv) infection of swiss albino mice. following intracerebral inoculation, virus antigen could be demonstrated by immunofluorescence in the splenic macrophages from day 4 and in peritoneal macrophages from day 5 post-infection, with a higher number of positive cells discernible on the 7th and 8th days. the virus could be isol ... | 1983 | 6644274 |
| dengue 2 vaccine: dose response in volunteers in relation to yellow fever immune status. | a live dengue 2 vaccine was tested in 38 volunteers in an evaluation of the safety, infectivity, and immunogenicity of doses of 10(1.8)-10(5.5) plaque-forming units. twenty yellow fever-immune and 18 yellow fever-nonimmune individuals received 0.5 ml of vaccine sc. immunization was dose related in yellow fever-immune volunteers, with a 50% immunizing dose of 10(3.3) plaque-forming units. in the group not immune to yellow fever, some but not all recipients of each vaccine dilution were immunized, ... | 1983 | 6655288 |
| treatment of intracranial dengue virus infections in mice with a lipophilic derivative of ribavirin. | rimantadine, ribavirin, and 6-mercapto-9-(tetrahydro-2-furyl)purine, administered intraperitoneally every 8 h for 7 days starting minutes after virus challenge, had no effect on survival and mean survival time of balb/c mice inoculated intracranially with dengue virus type 2. in contrast, intraperitoneal treatment with ribavirin 2',3',5'-triacetate, a lipophilic analog of ribavirin, effected significant increases in both mean survival time and survival rate, suggesting that ribavirin 2',3',5'-tr ... | 1983 | 6684897 |
| transovarial transmission of dengue 2 virus by aedes aegypti in nature. | dengue 2 virus was recovered from three of 123 pools of naturally infected aedes aegypti larvae (6,200 insects) collected from water containers in rangoon. the virus was also isolated from two of 76 pools (7,730 mosquitoes) of male ae. aegypti, collected as larvae and reared in the laboratory to adults. minimum field infection rates among these two groups of mosquitoes were 1:2,067 and 1:3,865, respectively. insect pools were inoculated into toxorhynchites splendens mosquitoes and dengue viral a ... | 1983 | 6859404 |
| plasma membrane-acting drugs inhibit the effect of dengue virus-induced cytotoxic factor. | our earlier studies reported that the cytotoxic factor (cf) produced in the spleen of dengue virus type 2-infected mice killed the lymphoid cells of many species of animals and induced normal mouse splenic and peritoneal macrophages to produce a cytotoxin (cf2). in the present study, it has been observed that pretreatment of target cells with cell plasma membrane stabilizers--2,4-dinitrophenol, ouabain and reduced glutathione--prevents the cytotoxicity of cf and blocks the production of cf2, but ... | 1983 | 6870195 |
| genetic variation among dengue 2 viruses of different geographic origin. | genetic variation in dengue 2 isolates from various geographic areas was examined by oligonucleotide fingerprinting of the 40 s genome rna. oligonucleotide maps of geographically isolated and epidemiologically unrelated viruses were very distinct. direct comparison of the oligonucleotide map of the dengue 2 prototype new guinea 2 virus, isolated in 1944, with the fingerprints of more recent isolates from the south pacific indicated that the genome of dengue 2 virus had undergone extensive change ... | 1983 | 6612990 |
| [isolation of dengue virus type 2 from the serum of patients using the suckling mouse and cultured llcmk2 cells]. | 1984 | 6438733 | |
| 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 ... | 1984 | 6208313 |
| lysis of dengue virus-infected cells by natural cell-mediated cytotoxicity and antibody-dependent cell-mediated cytotoxicity. | peripheral blood mononuclear cells (pbmc) from humans without antibodies to dengue 2 virus lysed dengue 2 virus-infected raji cells to a significantly greater degree than uninfected raji cells. the addition of mouse anti-dengue antibody increased the lysis of dengue-infected raji cells by pbmc. dengue 2 immune human sera also increased lysis of dengue-infected raji cells by pbmc. these results indicate that both pbmc-mediated cytotoxicity and antibody-dependent cell-mediated cytotoxicity (adcc) ... | 1984 | 6207308 |
| the effect of interferon on flaviviruses in vitro: a preliminary study. | the preliminary results of our study in vitro on the effect of interferon on flaviviruses showed that interferon alpha and interferon beta were more effective on je viruses vip local strain and jagar strain, but less on dengue virus type 2 strain. however, the effect of these 2 interferons on the 2 strains of je viruses were still variable which need further investigations. the je virus vip local strain seemed to be more susceptible to interferon than the japanese prototype jagar strain. thus, t ... | 1984 | 6330910 |
| in vivo inhibition by intact mouse serum of the activity of the flavivirus-induced t-suppressors of autoreactive t-lymphocytes. | in 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 ... | 1984 | 6147997 |
| the vector competence of colonized aedes (stegomyia) katherinensis for dengue-2 virus. | colonized aedes (stegomyia) katherinensis mosquitoes from australia were infected with the pr-159 strain of dengue-2 virus using a membrane feeding technique and by intrathoracic inoculation. virus replication to low levels was detected when mosquitoes infected by both routes were assayed using the virus-sensitive ae. pseudoscutellaris (lstm-ap-61) mosquito cell line in a microculture system. analysis by indirect immunofluorescence revealed the expected 100% infection rates in inoculated mosquit ... | 1984 | 6398536 |
| [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- ... | 1984 | 6098109 |
| dengue virus type 2 vaccine: reactogenicity and immunogenicity in soldiers. | a live dengue virus type 2 (dengue-2) vaccine (pr-159/s-1) was tested for reactogenicity and immunogenicity in a placebo-controlled, double-blind clinical trial involving 98 soldiers. seroconversion rates based on the development of neutralizing antibody to dengue-2 were 90% in 70 recipients with immunity to yellow fever and 61% in 28 vaccinees without such immunity (p less than .01). peak titers of neutralizing antibody were three times higher in recipients with antibody to yellow fever virus a ... | 1984 | 6376649 |
| quantity of dengue virus required to infect rhesus monkeys. | as part of a dengue vaccine study, it was necessary to determine how much virus was required to infect rhesus monkeys. serial dilutions of dengue 2 and 4 viruses were inoculated subcutaneously into groups of five monkeys and seroconversions determined on days 30 and 60 post-inoculation. the viruses were also titrated simultaneously in llc-mk2 cells and mosquitoes. it was calculated that 9.5 mosquito infectious doses 50 (mid50) of dengue 2 virus and 22 mid50 of dengue 4 virus were required to inf ... | 1985 | 2860743 |
| dengue virus induced polypeptide synthesis. brief report. | dengue 2 virus polypeptide synthesis was investigated in bhk21 cells. nine or ten virus induced polypeptides were identified, three of which are glycoproteins as demonstrated by tunicamycin treatment of infected cells. we performed pulse chase experiments, experiments with amino-acid analogs, protease inhibitors or pactamycin treatment of infected cells, to determine whether or not large polypeptide processing occurs. in some of these experiments a large polypeptide (p 130) was immunoprecipitate ... | 1985 | 4015406 |
| [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 ... | 1985 | 3886182 |
| the quantitative kinetic study of dengue viral antigen by flow cytometry. i. an in vitro study. | a system effective in the early diagnosis of dengue virus infection was developed. the time course kinetics of dengue virus type 2 (d-2) antigen in vitro were analyzed by flow cytometry. early profiles of d-2 were also studied quantitatively through this method of analysis. the early events of host cell and virus interaction were investigated: attachment, internalization and replication. from these early profiles, the time at which new viral synthesis was detectable differed with each individual ... | 1985 | 4036316 |
| effect of adjuvant vaccines on dengue virus type 2 immune ascitic fluid production. | in a comparison of dengue type 2 immune mouse ascitic fluid immunization schedules, a schedule in which adjuvant vaccines were not used produced neutralizing antibody titers that were specific and a mouse mortality rate that was lower, resulting in a greater yield of ascitic fluids. in the schedules in which emulsified adjuvant vaccines were used, the quality of the emulsion had little effect on antibody titer produced. | 1985 | 3980697 |
| genetic relationships of the dengue virus serotypes. | previous studies have compared rna genomes from the different dengue virus serotypes by cdna-rna hybridization using dengue-1 virus- and dengue-2 virus-specific cdna probes. these probes revealed that there is a close genetic relationship between dengue virus serotypes 1 and 4. in this communication, the cdna-rna hybridization results using dengue-3- and dengue-4-specific cdna probes to determine the genetic relatedness of all four dengue virus serotypes are reported. the results indicate that s ... | 1985 | 3839253 |
| [dengue 2 in eastern senegal: serologic survey in simian and human populations. 1974-85]. | after the previously reported isolations of dengue 2 virus in eastern senegal in 1974 and 1981-1982, a retrospective serological study on simian and human populations was carried out in the same area. we investigated 1,095 simian sera collected at regular intervals between 1974 and 1984 from wild caught monkeys and 1,783 human sera from young children less than 11 years old collected during punctual surveys after the rainy season from 1976 to 1985. sera were tested using hai test, cf test and fo ... | 1986 | 3769119 |
| partial sequence analysis of cloned dengue virus type 2 genome. | dengue virus (den) is a member of flaviviruses and contains a single, (+)-strand rna of approx. 11 kb. complementary dna copy of the rna was synthesized using reverse transcriptase and oligo(dt) as primer. the double-stranded dna copy was cloned at the psti site of puc13'-1 vector and was used to transform escherichia coli jm83. eleven transfomants were found to contain den insert as screened by colony hybridization. three clones were chosen for further characterization by nucleotide (nt), seque ... | 1986 | 3803928 |
| geographic classification of dengue-2 virus strains by antigen signature analysis. | dengue-2 virus strains from different locations were compared by t1-rnase-resistant oligonucleotide fingerprinting and antigen signature analysis. the latter technique involved construction of radioimmunoassays using monoclonal antibodies that recognize nine distinct dengue-2 type-specific and flavivirus cross-reactive epitopes over a range of antigen concentrations. a statistical method was used to align unknown dengue antigen concentrations in different strain preparations, allowing comparison ... | 1986 | 2429440 |