Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| differential production of endogenous pyrogen by human peripheral blood leucocytes following interaction with h3n2 or h1n1 influenza viruses of differing virulence. | fever and other constitutional effects of influenza (headache, myalgia, listlessness, nausea, shivering, anorexia and depression) result from liberation of endogenous pyrogen (ep) from phagocytes. these effects are milder for recent h1n1 influenza virus isolates than for h3n2 strains. interaction with human peripheral blood leucocytes in vitro showed that h1n1 strains, a/ussr/90/77 and a/fiji/15899/83, elicited significantly less ep (as assessed by the rabbit pyrogen assay) than two virulent clo ... | 1987 | 3504218 |
| [immunity of the populations of the ussr and east germany to reference strains of influenza viruses and the characteristics of a new antigenic variant of the virus]. | in 1985, a new epidemic variant of influenza virus, a/berlin/6/85 (h3n2) was isolated which differed antigenically from the reference a/philippines/2/82 virus. the results of the study of population immunity in adults and children of the ussr and gdr to these virus variants confirm the data on the continuing drift of virus a (h3n2). | 1987 | 3500544 |
| infectivity and reactogenicity of reassortant cold-adapted influenza a/korea/1/82 vaccines obtained from the usa and ussr. | the safety and immunogenicity of two live influenza a virus vaccine strains, the cr 59 and 17/25/1 cold-adapted (ca) reassortants, were evaluated in 170 healthy young adult volunteers. the vaccines were produced by recombining a/korea/1/82 (h3n2) wild-type virus with either a/ann arbor/6/60 (h2n2) or a/leningrad/134/17/57 (h2n2) ca donors of attenuation. both vaccines were well tolerated in volunteers. the 17/25/1 strain, prepared from a/leningrad, infected at least 70% of seronegative volunteer ... | 1987 | 3499246 |
| purified influenza virus nucleoprotein protects mice from lethal infection. | local administration of nucleoprotein purified from x31 (h3n2) influenza a virus primed for a virus cross-reactive cytotoxic t cells and resulted in substantial protection (75%) of mice from a lethal challenge with the heterologous mouse-adapted a/pr/8/34 (h1n1) virus. by following the course of a lethal virus challenge we found that nucleoprotein priming did not prevent virus infection but rather aided recovery. nucleoprotein-primed mice suffered initial symptoms of infection, i.e. weight loss ... | 1987 | 3493324 |
| bile immunoglobulin of the duck (anas platyrhynchos). ii. antibody response in influenza a virus infections. | the capacity of the igm-like bile immunoglobulin (igx) of the duck (anas platyrhynchos) to express antibody activity to h3n2 influenza a viruses, and the dependence of this activity on the co-existence of serum igm antibodies were investigated. ducklings infected orally and intranasally at 15-29 days of age with viruses isolated from different host species were examined for haemagglutination-inhibiting (hi) antibodies in biles and sera 16-29 days after infection (p.i.). all biles had antibodies ... | 1987 | 3451744 |
| [genetic recombination between natural isolates of influenza virus serotypes h1n1 and h3n2]. | oligonucleotide mapping of individual genes was used for search of possible genetic recombinants between natural isolates of influenza h1n1 and h3n2 viruses isolated in the ussr in 1977-1979. no antigenic hybrids and recombinants with the antigenic structure h3n2 were found, however, it was shown that isolates of h1n1 viruses of 1979 (the a/ussr/61/79 strain) might represent genetic recombinants carrying genes p1 + p2 from h3n2 viruses, the m-gene of the ussr/61/79 virus being closest in its str ... | 1987 | 3445583 |
| [effectiveness of annual booster inoculations against various influenza serotypes and the procedure for mass vaccination]. | the epidemiological observation during an outbreak of a (h3n2) influenza in february-march, 1983, showed that the third annual vaccination with killed influenza vaccine did not enhance the effectiveness of vaccinations in the populations under study. it was observed that 14 months after immunization, 55.9% of the subjects examined had antibody titres of 1:40 or higher to the a/bangkok/1/79 strain antigenically related to the vaccine strain, and 41% of the subjects of this group had antibodies to ... | 1987 | 3445582 |
| influenza a and b antibody status in tanzania. | sera from 200 babies and young children and from 205 mother-newborn pairs were tested for haemagglutination inhibiting antibody against three a-h1n1, one a-h2n2, four a-h3n2, and two influenza b viruses. the results indicated that a higher concentration of antibody against all influenza a and b viruses tested was found more frequently in maternal sera than in neonatal sera. high prevalences of antibody and high geometric mean titres against the a-h2n2-1957 and a-h3n2-1968 viruses from the eras 1 ... | 1987 | 3445328 |
| [evaluation of the potential use of inactivated influenza centrifuged vaccines with various hemagglutinin levels for immunizing schoolchildren]. | the safety, reactogenic properties and immunogenic potency of inactivated influenza centrifuged vaccines with different hemagglutinin content were studied in observations on children aged 11-15 and 7-10 years. according to the results of clinico-laboratory investigations, commercial influenza vaccine and its variant with hemagglutinin content reduced by half were found to be safe and showed faintly pronounced reactogenic properties in children. after vaccination hyperemia developed at the site o ... | 1987 | 3434050 |
| vaccination activity of live influenza vaccine in different seasons of the year. | reactogenicity, immunogenicity and viability of the vaccine virus were studied during vaccination of adults with live allantoic influenza vaccines of the types a (h1n1), a (h3n2) and b in different seasons of the year. seasonal oscillations of reactogenicity of the vaccines (minimum in summer, maximum in winter) were demonstrated. a decrease in the re-isolation rate of vaccine viruses and in their content in the secretions of the upper respiratory passages was observed in summer. seasonal oscill ... | 1987 | 3429857 |
| egg-grown and tissue-culture-grown variants of influenza a (h3n2) virus with special attention to their use as antigens in seroepidemiology. | a field strain of influenza a (h3n2) virus isolated in embryonated eggs during the 1984-5 influenza outbreak (a/finland/13/85e) was compared in an antigenic analysis with virus from the same clinical specimen isolated in mdck cell cultures (a/finland/13/85m). the m-virus appeared to be more sensitive to haemagglutination-inhibiting antibodies against heterologous viruses than did the e-virus. the results of propagation and plaque purification experiments support the hypothesis that a single clin ... | 1987 | 3428377 |
| [primary structure of the full-size dna copy of the influenza virus a/kiev/59/79 (h1n1) pb1 gene protein]. | nucleotide sequence of the a/kiev/59/79 influenza virus pb1 gene is reported, thus completing the full-genome primary structure of the recombinant between the virus and laboratory strain a/pr/8/34. the parental strain a/kiev/59/79 (h1n1) is, in turn, shown to be a natural reassortant inheriting its genes of polymerase complex (pb1, pb2, np and, in all probability, pa) from contemporary h3n2 influenza virus strains. | 1987 | 3426639 |
| an outbreak of influenza a (h3n2) in a hospital for the elderly with emphasis on pulmonary complications. | from dec 1, 1985 to jan 18, 1986, 133 of 379 (35.1%) mainly elderly in-patients at a hospital in fukuoka city were infected with influenza virus a (h3n2). in 32 of the 133 (24.1%) infected with the virus, pneumonia occurred. the occurrence was significantly higher in man (33.1%) than in women (17.1%) (p less than 0.05), and the same occurrence was found to be higher in bed-ridden patients (32.7%) than in ambulatory patients (17.3%) (p less than 0.05). it was also higher in those age 70 or older ... | 1988 | 3418982 |
| comparative activities of several nucleoside analogs against influenza a, b, and c viruses in vitro. | a set of 20 nucleoside analogs were examined for their inhibitory effects on the cytopathogenicity and growth of influenza virus type a, b, and c strains in madin-darby canine kidney (mdck) cells. among the compounds evaluated, pyrazofurin, 3-deazaguanine, ribavirin, carbodine, and cyclopentenyl cytosine inhibited viral cytopathogenicity at concentrations that were lower than those found cytotoxic for the mdck cells. no differences were observed in the 50% effective doses (based on inhibition of ... | 1988 | 3415210 |
| human influenza viral neuraminidases augment cell-mediated cytotoxicity in vitro. | previously, we reported that influenza virus-induced cell-mediated cytotoxicity (cmc) was largely due to its glycoproteins, hemagglutinin and neuraminidase (na). these observations were based on the use of a single influenza virus strain, the a/port chalmers/3/73 (h3n2), and these were considered insufficient to generalize that all human influenza virus nas augment cmc. therefore, antigenically different nas of human influenza strains were used to study whether (a) all nas possess the potential ... | 1988 | 3412358 |
| characterization of envelope antigens of influenza a (h3n2) virus isolated during 1983-1985 epidemics and from sporadic cases of infection. | ten strains of influenza a (h3n2) virus isolated from an outbreak in 1983, and ten strains isolated in 1985 from sporadic cases of infection were included in the study. for characterization of envelope antigens were used the polyclonal and monoclonal antibodies tested in the reaction of haemagglutinin inhibition, neuraminidase inhibition, and by lectin test. the strains but slightly different in the tests with polyclonal antibodies could clearly be classified to 3-4 groups using 5 monoclonal ant ... | 1988 | 3411119 |
| antigenic and structural characterization of multiple subpopulations of h3n2 influenza virus from an individual. | influenza viruses grown in embryonated chicken eggs frequently possess antigenically distinguishable hemagglutinin (ha) compared to virus from the same source grown in mammalian cell culture. to further investigate the extent of variation among viruses from an individual, viruses were isolated from throat washes collected over a 48-hr period during infection with influenza virus designated a/mem/6/86 (h3n2). viruses were isolated from limit dilutions in eggs and mammalian madin-darby canine kidn ... | 1988 | 3407150 |
| local and systemic antibody responses in high-risk adults given live-attenuated and inactivated influenza a virus vaccines. | forty seropositive older adults with chronic diseases were vaccinated intranasally with either influenza a/california/10/78 (h1n1) (cr37) or influenza a/washington/897/80 (h3n2) (cr48) virus. no clinically significant decrements in pulmonary function occurred postvaccination. eight (62%) recipients of cr37 virus and 16 (59%) recipients of cr48 virus became infected with vaccine virus, as indicated by a fourfold rise in nasal wash immunoglobulin g (igg) or iga antibody titer, a fourfold rise in s ... | 1988 | 3384914 |
| antibody responses of swine to type a influenza viruses during the past ten years in japan. | a total of 6346 swine sera collected at an abattoir in the city of obihiro, hokkaido during the years 1978-87 were tested for the presence of antibodies to swine and human influenza viruses. a high incidence of antibody to a/new jersey/8/76 (swine type h1n1) virus was observed throughout the 10 years except for the occasional month and a single long period of 15 months. antibodies to human h3n2 virus in swine appeared to be related to the epidemics of human influenza which occurred in the study ... | 1988 | 3378588 |
| host cell-mediated selection of influenza a (h3n2) virus variant subpopulations: lack of association between antigenic and receptor-binding properties. | during the outbreak of influenza due to a (h3n3) viruses in finland in 1985/6 virus pairs were isolated from the same clinical specimens in embryonated hens' eggs (ce) and in canine kidney cell cultures (mdck). some of these isolates, the e and m pairs, were distinguished by their reactions in haemagglutination inhibition (hi) tests carried out using polyclonal antisera, and by receptor-binding properties, as evidenced by differences in their elution activity from erythrocytes. passage of the e- ... | 1988 | 3378587 |
| influenza virus infection of tracheal gland cells in culture. | influenza virus-induced tracheobronchitis causes limited epithelial deciliation but markedly decreased mucociliary transport. this suggests that virus-induced alterations in airway mucus play a role in decreased mucociliary transport. airway submucosal glands are a primary source of mucus. therefore, we examined virus-gland cell interactions by exposing primary cultures of isolated feline tracheal gland cells to influenza a/scotland/840/74 h3n2 virus for 1 h at a multiplicity of infection of 0.1 ... | 1988 | 3357204 |
| epidemiology of acute respiratory illness during an influenza outbreak in a nursing home. a prospective study. | we observed an influenza epidemic caused by influenza a/arizona/82 (h3n2) in a nursing home during 1982 to 1983. a survey indicated that 59% of the residents were immunized before the outbreak. the outbreak was observed to begin in november, peak in february, and disappear in april. a significant level of herd immunity may have accounted for the slow progression through the nursing home. in addition, serologic evidence of concurrent infection with respiratory syncytial virus, parainfluenza virus ... | 1988 | 3341856 |
| immunization of elderly people with high doses of influenza vaccine. | healthy ambulatory elderly were immunized with increasing doses of the 1984-1985 influenza vaccine formulation. two types of vaccines, split-product vaccine (spv) and whole virus vaccine (wvv), were used. three different doses, 0.5 ml (the standard volume, 1x), or 1.0 ml (2x), and 1.5 ml (3x) of each of the two vaccines were compared. the size of each of the six groups was between 23 and 26 subjects. the mean ages in each of the groups ranged from 71 to 74 years. no difference in local or system ... | 1988 | 3339228 |
| efficacy of sequential annual vaccination with inactivated influenza virus vaccine. | inactivated influenza virus vaccine efficacy after annual revaccination has been reported to be less than that after first vaccination in boarding school children. we prospectively examined the immunogenicity and efficacy of this vaccine in healthy 30- to 60-year-old volunteers in houston, texas, over two epidemic seasons (1983-1985) encompassing outbreaks due to influenza a (h3n2 and h1n1) and influenza b viruses. a placebo group that had never (or not in recent years) received inactivated infl ... | 1988 | 3337087 |
| origin of the hemagglutinin gene of h3n2 influenza viruses from pigs in china. | influenza viruses of the h3n2 subtype similar to aichi/2/68 and victoria/3/75 persist in pigs many years after their antigenic counterparts have disappeared from humans (shortridge et al. (1977). science 19, 1454-1455). to provide information on the mechanism of conservation of these influenza viruses in pigs, the hemagglutinin (ha) of four isolates from swine derived from taiwan and southern china were analyzed antigenically and genetically. the reactivity pattern of these viruses with a panel ... | 1988 | 3336940 |
| four viral genes independently contribute to attenuation of live influenza a/ann arbor/6/60 (h2n2) cold-adapted reassortant virus vaccines. | clinical studies previously demonstrated that live influenza a virus vaccines derived by genetic reassortment from the mating of influenza a/ann arbor/6/60 (h2n2) cold-adapted (ca) donor virus with epidemic wild-type influenza a viruses are reproducibly safe, infectious, immunogenic, and efficacious in the prevention of illness caused by challenge with virulent wild-type virus. these influenza a reassortant virus vaccines also express the ca and temperature sensitivity (ts) phenotypes in vitro, ... | 1988 | 3336068 |
| [virological studies in fatal outcomes in influenza and its complications in adults during the period of influenza a (h3n2) virus circulation from 1969 to 1983]. | in the period of circulation of influenza a (h3n2) virus, 1969-1983, we examined virologically the autopsy specimens from 69 adults who died of influenza and its complications. immunofluorescence examinations of organ impressions and infected cultures as well as virus isolations were used for postmortem laboratory diagnosis. influenza viruses were isolated postmortem in all age groups, predominantly in older subjects (over 60), both in cases of early and late (after 7 days) deaths. the viruses w ... | 1987 | 3324479 |
| sequential infection or immunization of ferrets with a series of influenza a (h3n2) strains (report to the medical research council's sub-committee on influenza vaccines (cdvip/iv)). | previous studies of boys at christ's hospital school have indicated that annual immunization with influenza virus vaccines did not significantly reduce the total incidence of influenza infection compared to unimmunized subjects. in view of the implications of this result, a similar study was conducted in ferrets to clarify these findings. groups of ferrets were immunized or infected with a series of influenza a (h3n2) viruses over an 18-month period, and the immunity to subsequent live virus cha ... | 1987 | 3315713 |
| [the circulation of influenza virus in human communities subjected to the action of noxious chemical substances]. | investigations were conducted during 1985 and 1986 years on the effect of some noxious chemicals on the influenza virus circulation in an industrial enterprise community. the presence of influenza virus type a (h1n1), a (h3n2) and b was revealed by immunofluorescence in exfoliated cells collected from nasopharynx. the kinetic of type specific hemagglutination inhibiting antibodies was followed monthly. chick embryos were used to isolate influenza virus strains. meaning of the results is discusse ... | 1987 | 3310379 |
| children with influenza a infection: treatment with rimantadine. | treatment with rimantadine of influenza in children and the potential development of resistance in clinical isolates associated with therapy have not been previously studied. we compared rimantadine to acetaminophen therapy in a controlled, double-blind study of 91 children with influenza-like illness. of 69 children with proven influenza a/h3n2 infection, 37 received rimantadine and 32 received acetaminophen for five days. children receiving rimantadine showed significantly greater reduction in ... | 1987 | 3302925 |
| a new concept of the epidemic process of influenza a virus. | influenza a virus was discovered in 1933, and since then four major variants have caused all the epidemics of human influenza a. each had an era of solo world prevalence until 1977 as follows: h0n1 (old style) strains until 1946, h1n1 (old style) strains until 1957, h2n2 strains until 1968, then h3n2 strains, which were joined in 1977 by a renewed prevalence of h1n1 (old style) strains. serological studies show that h2n2 strains probably had had a previous era of world prevalence during the last ... | 1987 | 3301379 |
| [analysis of the potentials of molecular hybridization of nucleic acids as a method of the laboratory diagnosis of influenza]. | the possibilities of using the dna copies of different genes of influenza a virus for the detection of virus-specific rna by molecular dot hybridization have been studied. high specificity and sensitivity of the rna determination techniques have been demonstrated, as well as the efficacy of using dna probes with the sequences of conservative genes (polymerase, nucleoprotein and matrix genes) for the detection of influenza a virus subtypes h1n1, h2n2, h3n2 and probes with the copies of the corres ... | 1988 | 3291499 |
| genetic basis of resistance to rimantadine emerging during treatment of influenza virus infection. | the emergence of influenza a viruses which had acquired resistance to rimantadine during a clinical trial (c. b. hall, r. dolin, c. l. gala, d. m. markovitz, y. q. zhang, p. h. madore, f. a. disney, w. b. talpey, j. l. green, a. b. francis, and m. e. pichichero, pediatrics 80:275-282, 1987) provided the opportunity to determine the genetic basis of this phenomenon. analysis of reassortant viruses generated with a resistant clinical isolate (h3n2) and the susceptible influenza a/singapore/57 (h2n ... | 1988 | 3282079 |
| antigenic heterogeneity within influenza a (h3n2) virus strains. | on the basis of their antigenic properties, influenza virus strains are classified into types and subtypes, which are further subdivided into variants that differ to various degrees in haemagglutination-inhibition assays. evidence is presented that during infection with an influenza a(h3n2) virus the respiratory tract of a human patient often harbours more than one antigenic virus variant. these variants are frequently propagated by embryonated fowl eggs and monkey cells with different efficienc ... | 1988 | 3260141 |
| prophylactic use of amantadine in a boarding school outbreak of influenza a. | amantadine was used in a boarding school to control an outbreak of influenza a h3n2. of 859 pupils 79% took amantadine and almost all of them completed the course (100 mg per day for 15 days). while amantadine was being taken the number of clinical cases of influenza was considerably fewer than that predicted on the basis of previous outbreaks of influenza a at the school. however, during the month following the course of amantadine, the outbreak continued with many clinical cases confirmed by v ... | 1988 | 3256644 |
| immunostimulating agents against influenza virus infection in senescent rats. | this study investigated the nonspecific immunomodulatory effects of bacillus calmette-guerin (bcg), muramyl dipeptide (mdp) and ascorbic acid (vitamin c) on virus infection of the respiratory tract in fischer-344 rats. groups of young adult (12-16 months old) and aged (24-30 months old) rats were given bcg or mdp intranasally or vitamin c orally 6 weeks and again 3 days before an intranasal challenge with influenza virus a/bangkok/h3n2 (10(6) 50% eid). titers of hemagglutinin in lung homogenates ... | 1988 | 3228058 |
| a study of intranasally administered interferon a (rifn-alpha 2a) for the seasonal prophylaxis of natural viral infections of the upper respiratory tract in healthy volunteers. | the efficacy of interferon a (rifn-alpha 2a), an escherichia coli-derived interferon, in the prophylaxis of acute upper respiratory tract infection, was evaluated in a community-based double-blind placebo-controlled study in the australian winter of 1985. the trial population of 412 healthy volunteers (190 males and 222 females, aged 18-65 years) self-administered 1.5, 3.0 and 6.0 megaunits (mu) of interferon a per day or a placebo, intranasally for 28 days. the period of study coincided with an ... | 1988 | 3215290 |
| [genetic basis of influenza virus virulence: gene composition and virulence of reassortants between mouse-adapted and nonadapted strains from different subtypes]. | reassortment analysis of the pneumovirulence for mice marker of influenza virus has been performed. the original a/ussr/90/77 (h1h1) influenza virus strain or its mouse-adapted variant were crossed with a variant of a/aichi/2/68 (h3n2) influenza virus highly virulent for mice. the reassortant having ha gene of the original a/ussr/90/77 virus and the other genes of the highly virulent a/aichi/2/68 strain was avirulent for mice, whereas a similar reassortant possessing ha gene of the mouse-adapted ... | 1988 | 3211186 |
| surveillance of influenza a and b viruses in italy between 1984 and 1987. | antigenically heterogeneous strains and new variants of influenza a viruses, both a (h3n2) and (h1n1) subtypes, as well as influenza b strains were detected in italy in a period, between 1984-1987, characterized by a moderate degree of influenza activity. each year the evaluation, by srh technique, of antibodies, in the population, to currently circulating viruses, has confirmed the extent of infection and often the prevalent virus. | 1988 | 3203724 |
| comparison of live, attenuated h1n1 and h3n2 cold-adapted and avian-human influenza a reassortant viruses and inactivated virus vaccine in adults. | the infectivity, immunogenicity, and efficacy of live, attenuated influenza a/texas/1/85 (h1n1) and a/bethesda/1/85 (h3n2) avian-human (ah) and cold-adapted (ca) reassortant vaccines were compared in 252 seronegative adult volunteers. the immunogenicity and efficacy of the h1n1 reassortant vaccine were also compared with those of the trivalent inactivated virus vaccine. each reassortant vaccine was satisfactorily attenuated. the 50% human infectious dose was 10(4.9) for ca h1n1, 10(5.4) for ah h ... | 1988 | 3198936 |
| epidemiologic features of influenza in a large urban centre (b.) in romania, in 1987. | the study presents the peculiarities of influenza evolution in 1987 in a large town in romania. these features were defined by a complex methodology, based on clinical, epidemiologic and laboratory investigations, used in the active control of the epidemiologic process kinetics. the influenza viruses type a (h1n1 and h3n2) had a major role in the infecting and immunizing contacts in all age groups whereas the influenza virus type b had a reduced circulation. the epidemiologic influenza impact in ... | 1988 | 3195054 |
| the carbohydrate chains of influenza virus hemagglutinin. | the major surface antigen of influenza virus a/leningrad/385/80 (h3n2), h3 hemagglutinin, as well as its heavy and light subunits were obtained by bromelain treatment, followed by gel chromatography. carbohydrate chains were split off from both subunits by lithium borohydride-lithium hydroxide in aqueous 2-methyl-2-propanol, and individual oligosaccharides isolated. the main oligosaccharides, whose structure was determined by 1h-n.m.r. spectroscopy and chemical methods, are of the ordinary oligo ... | 1988 | 3191507 |
| analysis of virus and host factors in a study of a/peking/2/79 (h3n2) cold-adapted vaccine recombinant in which vaccine-associated illness occurred in normal volunteers. | live attenuated cold-adapted influenza vaccine is undergoing evaluation in man. several strains have proven to be safe, immunogenic, nontransmissible, and protective against experimental challenge. in this study of a/peking/2/79(h3n2), with six internal genes from the cold-adapted (ca) parent a/ann arbor/6/60(h2n2), we encountered at the highest input multiplicity, 28% illness rate among individuals infected with vaccine. reversion to wild type and excessive viral replication did not occur. phys ... | 1988 | 3183640 |
| [design of a recombinant strain of the vaccinia virus containing an expressible gene for influenza a virus hemagglutinin]. | a recombinant vaccinia virus (vv) strain containing a cloned gene of influenza a/udorn/307/72 (h3n2) hemagglutinin (ha) gene has been produced. ha expression in cv-1 cells infected with the recombinant virus was determined by enzyme immunoassay. the influenza virus ha titer was 1:64-1:128. when rabbits were inoculated intravenously with the recombinant vav, antibody titres were 1:5120. the recombinant vav preparation may be used for generation of monospecific antibody to influenza virus. | 1988 | 3176425 |
| antigenic and biochemical analysis of influenza "a" h3n2 viruses isolated from pigs. | four influenza a-h3n2 viruses isolated in pigs from different herds in central italy in the period 1981/82 have been antigenically and biochemically analysed. three of them a/sw/italy/2/81, a/sw/italy/7/81, a/sw/italy/8/82 were found to be serologically related to a/bangkok/1/79 (h3n2). these three viruses were shown to have an identical electrophoretic pattern, as regards virus induced polypeptides and were clearly distinguishable from the virus a/sw/italy/6/81 which was antigenically related t ... | 1985 | 3155941 |
| murine th response to influenza virus: recognition of hemagglutinin, neuraminidase, matrix, and nucleoproteins. | balb/c mice were primed with type a influenza virus by footpad injection or by aerosol infection with pr8 [a/pr/8/34-(h1n1)]. isolated t cells from draining lymph nodes were then tested for their proliferation in the presence of purified viral proteins hemagglutinin, neuraminidase, matrix, and nucleoprotein. significant responses [( 3h]thymidine incorporation) were seen against each of the four proteins after either priming scheme. when helper t (th) cell clones were isolated by hybridoma format ... | 1985 | 3155776 |
| [effect of influenza virus infection on arachidonic acid cascade in mouse thrombocytes]. | prostaglandins (pgs) are essential for many physiological and pathological processes. as they are not stored in tissue, their presence and actions therefore result from de novo synthesis and release. although platelets themselves appear to have the ability to synthesize txa2, pgd2, arachidonic acid may also be metabolized in the lipoxygenase pathway in platelets, producing 12-hydroperoxy/12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-hpete/12-hete). cflp mice were infected intranasally with a/h3 ... | 1986 | 3094271 |
| susceptibility to virus infection with exposure to nitrogen dioxide. | the interaction between nitrogen dioxide (no2) exposure and human susceptibility to respiratory virus infection was investigated in a placebo-controlled, randomized, blinded trial that was conducted in an environmentally controlled research chamber over a three-year period. healthy, non-smoking volunteers, 18 to 35 years old, who were seronegative to influenza a/korea/82 (h3n2) virus, were randomly assigned either to breathe filtered clean air (clean air group) or nitrogen dioxide (exposure grou ... | 1988 | 3077322 |
| [isolation and characteristics of monoclonal antibodies to influenza virus types a and b]. | monoclonal antibodies (mca) to influenza type a (10f) and b (5h and 6h) viruses have been prepared. by immunoblotting method, mca 10f were found to be specific for np-protein of influenza a virus, and mca 5h and 6h to be specific for hemagglutinin of influenza b virus. it was established that the 10f clone interacted with all the investigated influenza a virus strains with different antigenic formulae (h1n1, h2n2, h3n2) and could be used for typing of this virus type. clones 5h and 6h react spec ... | 1988 | 3064429 |
| [identification of the hemagglutinating antigens of the influenza virus by immunoenzyme analysis]. | highly active test sera detecting the presence of virus antigen both in concentrated and purified preparations and in allantoic virus cultures directly adsorbed on the solid phase have been proposed for successful identification and detection of influenza a and b virus variants. after direct sorption of purified and concentrated virus preparations, the test sera to influenza a (h1n1, h2n2, h3n2) virus detect the virus antigen in a concentration of 8 ng/ml, test sera to influenza b virus in a con ... | 1988 | 3064428 |
| an improved membrane-filtration enzyme immunoassay for the rapid serological diagnosis of viral infections. | a one-step modification of the membrane-filtration enzyme immunoassay (mf eia) (barnett et al., j. clin. microbiol., 23:385-399, 1987), for estimation of virus-specific antibody is described. the modified mf eia allowed serum, antigen and enzyme-conjugated anti-globulin to be incubated together in membrane-based 96-well plates to enable the formation of immune complexes in solution at 37 degrees c. the assay required only 45 min for completion and polyethylene glycol was shown to be an essential ... | 1988 | 3053742 |
| prevalence of hong kong (h3n2) influenza virus-antibody in swine. | 1985 | 2995716 | |
| epidemiological features of influenza in a large town of romania during 1983. | data supplied by the active influenza surveillance - including clinical, epidemiological and laboratory investigations - allowed the characterization of the particularities of an influenza outbreak caused by a(h3n2) virus in a large town of romania in march 1983. the epidemiological impact of influenza in 1983 is discussed in the light of the complex relationships between the antigenic structure of circulating influenza strains and the profile of antiinfluenza immunity of the population. | 1985 | 2988190 |
| clinical-histopathological correlations in experimental otitis media: implications for silent otitis media in humans. | clinical-histopathological correlations were sought in an experimental animal model of otitis media. among 20 chinchillas inoculated intranasally with wildtype influenza a/alaska virus (h3n2) and type 7f streptococcus pneumoniae, 15 animals (18 ears) developed otoscopic and tympanometric signs of otitis media with middle ear effusion. middle ear inflammation was most intense 10 days after virus inoculation. twenty-two days after virus inoculation, eight ears showed diffuse middle ear histopathol ... | 1985 | 2987783 |
| detection of viral and chlamydial antigens in open-lung biopsy specimens. | the recovery of viruses and chlamydia trachomatis from cell cultures and the detection of their antigens in impression smears prepared from open-lung biopsy (olb) specimens from immunocompromised adults were compared. touch impression smears were prepared on three slides, each containing eight wells. olb tissue was homogenized (stomacher) and inoculated into mrc-5, primary monkey kidney, and mccoy cell cultures. the direct and indirect immunofluorescence (if) tests were used to detect antigens t ... | 1985 | 2983526 |
| identification of sequence changes in the cold-adapted, live attenuated influenza vaccine strain, a/ann arbor/6/60 (h2n2). | nucleotide sequences have been obtained for rna segments encoding the pb2, pb1, pa, np, m1, m2, ns1, and ns2 proteins of the influenza a/ann arbor/6/60 (h2n2) wild-type (wt) virus and its cold-adapted (ca) derivative that has been used for preparing investigational live attenuated vaccines. twenty-four nucleotide differences between the ca and wt viruses were detected, of which 11 were deduced to code for amino acid substitutions in the ca virus proteins. one amino acid substitution each was pre ... | 1988 | 2974219 |
| the influence of human immunodeficiency virus (hiv) infection on antibody responses to influenza vaccines. | to ascertain whether subjects infected with human immunodeficiency virus (hiv) generally develop protective hemagglutination inhibition antibody responses to inactivated influenza vaccines. | 1988 | 2970238 |
| [biological characteristics of epidemic and interepidemic strains of the influenza a (h3n2) virus]. | comparative studies of biological properties of influenza a (h3n2) viruses isolated in the epidemics of 1980 and 1983 and in the interepidemic period of 1982 showed a sharp reduction of the biological activity of the interepidemic viruses as compared with that of the epidemic ones. this was manifested by low isolation rate of virus in the interepidemic period, reduced hemagglutinating, interfering, and immunogenic activity of these viruses, poor reproduction in the lung tissue of white mice and ... | 1987 | 2963436 |
| specific antibody responses by high- and low-density human peripheral blood b cells: t-helper cells and t-cell replacing factor (trf) act on different b-cell subpopulations. | antibody production to influenza a strain virus x31 (h3n2) was measured in cultures of peripheral blood mononuclear cells (pbmc) stimulated with either antigen (x31) or pokeweed mitogen (pwm). with some donors, x31 antibody was produced in response to antigenic stimulation, but not as part of the polyclonal response to pwm, suggesting that antigen and pwm may be acting on different b-cell subpopulations. to test this hypothesis, t-cell depleted pbmc (e-) cells were fractionated on discontinuous ... | 1987 | 2959615 |
| antigen-presenting b cells and helper t cells cooperatively mediate intravirionic antigenic competition between influenza a virus surface glycoproteins. | parenteral vaccination of balb/c mice primed by infection with h3n2 variants of influenza a virus results in a reduced production of n2 antibody in response to homologous (h3n2) vaccine compared with the response to an h7n2 vaccine equal in n2 immunologenicity. we now have studied the interaction in vitro of purified splenic b and t lymphocytes from variably immunized mice to ascertain the cellular basis of the hemagglutinin (ha)-influenced antibody response to neuraminidase (na). assay of the p ... | 1987 | 2958849 |
| immunologic response to influenza virus neuraminidase is influenced by prior experience with the associated viral hemagglutinin. iii. reduced generation of neuraminidase-specific helper t cells in hemagglutinin-primed mice. | in balb/c mice primed by influenza virus infection to h3 hemagglutinin and n2 neuraminidase, presentation of n2 in association with a heterosubtypic (h7) hemagglutinin results in production of a greater amount of n2 antibody than is found with homologous (h3n2) reimmunization. titration of primed helper t cell (th) activity by adoptive transfer of purified t cells to athymic mice given h6n2 vaccine demonstrates a lesser number of n2-specific th cells in mice subjected to homologous reimmunizatio ... | 1987 | 2957444 |
| [influenza morbidity in the kazakh ssr 1977-1984]. | in 1977-1984, 6 epidemic outbreaks of influenza were recorded in the republic of which 2 were due to influenza a (h1n1), 2 to a (h3n2) and 2 to influenza b virus. the epidemics of influenza h1n1 (1977-1978, 1981) and h3n3 (1979-1980, 1983) were characterized by gradual decrease of their intensity as manifested by lowering of the morbidity rate and frequency of virus isolation. on the contrary, epidemics of influenza b showed a certain trend to increase. an important feature of the epidemics etio ... | 1986 | 2945325 |
| suicide selection of murine t helper clones specific for variable regions of the influenza hemagglutinin molecule. | a negative selection procedure has been developed to obtain murine t helper clones specific for variable regions of the influenza a hemagglutinin. t cell lines, established from mice primed by intranasal infection with x31 (h3n2) virus, were cross-stimulated with natural variant viruses of known primary sequence (either a/texas/1/77 or a/eng878/69) and proliferating cells eliminated by treatment with the cell cycle-specific drug 5-bromodeoxyuridine. after two suicide cycles, t cell lines were su ... | 1986 | 2941307 |
| [virological and pathomorphological study of an influenzal infection in children 1982-1983]. | in the interepidemic period of 1982-1983, acute respiratory viral infections and pneumonias in infants in alma-ata were in 40.2% of cases etiologically associated with influenza infection. in the studied period in alma-ata and during an epidemic outbreak of influenza in kzyl-orda (march, 1983), two influenza a virus subtypes, h1n1 and h3n2, were in circulation. in a number of cases these subtypes were isolated from the same infants. | 1985 | 2932855 |
| location of influenza virus m, np and ns1 proteins in microinjected cells. | when microinjected as cloned dna, the nucleoprotein (np) of influenza virus a/nt/60/68 (h3n2) accumulated in the nuclei of xenopus laevis oocytes, and cultured cells of rodent and primate origin. this accumulation appeared to be specific and a property of the np itself (or conceivably np in association with unknown cellular constituents) since no other influenza virus components were present in dna-injected cells. in the oocyte nucleus, clonally derived np achieved an eightfold concentration ove ... | 1985 | 2932535 |
| occupational exposure to influenza--introduction of an index case to a hospital. | the epidemiology of influenza in the hospital is frequently confounded by failure to separate community-acquired from nosocomial transmission. an 83-year-old woman was hospitalized one day after returning from asia with complications resulting from acute influenza a (h3n2) infection; she was the first culture-confirmed case in the region during the 1987-1988 influenza season, and her illness antedated other influenza cases in the area by at least four weeks. the patient shed virus at least four ... | 1989 | 2926107 |
| [specific and nonspecific indicators of activation of influenza viruses before an epidemic caused by influenza viruses subtype a/h3n2 and type b in czechoslovakia in 1986]. | the authors submit an aetiological and epidemiological analysis of the influenza epidemic which occurred in the csr between the 4th and 14th week of 1986 and was caused by the influenza virus subtype a/h3n2/ and type b. the epidemic affected a total of 27.1% of the population, in the age group of 0-5 years 63.7%, in the age group 6-14 years 52.7% and in the age group above 15 years 17.1%. in the course of the epidemic 77,458 cases of pneumonia and bronchitis were reported and 1,412 deaths with t ... | 1989 | 2920398 |
| purified influenza virus hemagglutinin and neuraminidase are equivalent in stimulation of antibody response but induce contrasting types of immunity to infection. | balb/c mice immunized with graded doses of chromatographically purified hemagglutinin (ha) and neuraminidase (na) antigens derived from a/hong kong/1/68 (h3n2) influenza virus demonstrated equivalent responses when ha-specific and na-specific serum antibodies were measured by enzyme-linked immunosorbent assays (elisas). antibody responses measured by hemagglutination inhibition or neuraminidase inhibition titrations showed similar kinetic patterns, except for more rapid decline in hemagglutinati ... | 1989 | 2915381 |
| resistance of influenza a virus to amantadine and rimantadine: results of one decade of surveillance. | all clinical isolates of influenza a viruses from patients in huntington, west virginia, during the decade 1978-1988 were tested, and 65 of 65 h1n1 and 176 of 181 h3n2 viruses were susceptible to the antiviral action of amantadine and rimantadine. the five resistant viruses were obtained from three members of a family undergoing therapy or prophylaxis with rimantadine. resistant influenza emerged during treatment with rimantadine and spread to two family contacts, causing typical influenza with ... | 1989 | 2915166 |
| comparison of the virologic and immunologic responses of volunteers to live avian-human influenza a h3n2 reassortant virus vaccines derived from two different avian influenza virus donors. | we compared the abilities of the six internal rna segments of two avian influenza viruses, a/mallard/alberta/88/76 (h3n8) and a/mallard/ny/6750/78 (h2n2), to confer attenuation on wild-type human influenza a/bethesda/1/85 (h3n2) virus in seronegative adult volunteers. live avian-human influenza a reassortant virus vaccines derived from either avian virus parent were comparable in the following properties: safety, infectivity, immunogenicity, and genetic stability. since the avian influenza a/mal ... | 1989 | 2913033 |
| action of epsilon-aminocaproic acid on the proteolysis system during experimental influenza in mice. | proteolysis system was examined in influenza-virus-infected mice after a 5-day course of therapeutic or preventive treatments with the proteolysis inhibitor epsilon-aminocaproic acid (e-aca). the mice were infected with nonadapted influenza virus a/hong kong/1/68 (h3n2). e-aca was shown to exert a pathogenetic action expressed by a marked tendency to normalization of elevated alkaline protease activity in damaged lung tissue and in the blood of infected animals. e-aca induced a long-lasting high ... | 1988 | 2906223 |
| clinico-immunologic and allergologic studies with the inactivated influenza virus vaccine purified and concentrated by gradient centrifugation. | vaccination activity and safety of inactivated influenza centrifugal divaccine have been studied in groups of subjects aged 18 to 22, 15 to 16, and 9 to 14 years. the vaccine tested contained either a standard dose (6-8 micrograms) or double a dose (12-16 micrograms) of the haemagglutinin (ha) of influenza viruses a(h1n1) and a(h3n2). the double antigenic load of the vaccine did not enhance its reactogenicity for adults or adolescents aged 15 to 16 years. it enhanced, however, the production of ... | 1988 | 2906221 |
| resistance of mice to reinfection after e-aminocaproic acid treatment of primary influenza virus infection. | the effect of proteolysis inhibitors on the formation of resistance to virus challenge has been studied in experimental influenza of mice. e-aminocaproic acid (e-aca) when used in the treatment of influenza decreased the virus reproduction in lungs and also enhanced the humoral immune response. the antibody titre on days 14 to 21 post infection (p.i.) was significantly higher in the treated animals. on day 30 after challenge with the homologous strain (h3n2) the virus reproduced to low levels in ... | 1988 | 2899958 |
| simultaneous determination of the level of antibodies to influenza virus surface and internal proteins by enzyme-linked immunosorbent assay. | enzyme-linked immunosorbent assay (elisa) has been adopted for simultaneous determination of the levels of antibodies to different influenza virus proteins in human sera with known haemagglutination-inhibition (hi) titre. whole virus of serotypes h1n1 and h3n2, haemagglutinin (ha), matrix (m) and nucleoprotein (np) proteins have been used as antigens. for detection of antibodies bound to the antigen, peroxidase labelled staphylococcus protein a conjugate has been used. correlation of the elisa a ... | 1988 | 2899957 |
| clinical and morphologic studies on the guinea pig eye infected with human influenza virus strains of different virulence. | human influenza virus serotypes h3n2 and h2n2 caused iridocyclitis and uveitis when inoculated at does of 10(6) 6.5 eid50 into the guinea pig eye anterior chamber. virulent influenza virus strains and their attenuated variants prepared by passaging in chick embryos (ce) have been compared in this model. these studies showed that virulent viruses cause more severe damage in the eyes than the attenuated strains. | 1987 | 2892383 |
| studies on influenza-virus virulence in recombinants between epidemic and vaccine strains. | influenza virus recombinants between epidemic strains a/brazil/11/78 (h1n1), a/ussr/382/78 (h3n2) and vaccine strains a/leningrad/9/46 (h1n1), a/victoria/35/72/50 (h3n2) have been tested for virulence for humans and albino mice; their genome structure has also been determined. it has been shown that after the replacement of surface antigens of a/leningrad/9/46 (h1n1) strain by surface antigens of a/brazil/11/78 (h1n1) or a/ussr/382/78 (h3n2), strains, the virus becomes totally nonpathogenic for ... | 1987 | 2891277 |
| a simple and rapid characterization of influenza virus isolates by monoclonal antibodies in radioimmunoassay. | radioimmunoassay (ria) with infectious allantoic fluid directly bound to solid phase, suitable for detection and further characterization of influenza virus isolates, is described. this simple and rapid method was applied for description of isolates obtained from different regions of czechoslovakia during influenza epidemic in 1983. the results confirmed that all 13 examined isolates represent influenza a viruses possessing h3 subtype haemagglutinin very similar to haemagglutinin of influenza vi ... | 1986 | 2874733 |
| characterization of influenza a-1983 epidemic strains by polyclonal and monoclonal antibodies and detection of two co-circulating antigenic variants. | influenza virus strains isolated during 1985 epidemic in czechoslovakia proved to be antigenically closely related to a/bangkok/79, a/philippines/2/83 and a/texas/77 (all h3n2) viruses, if examined in haemagglutination inhibition (hi) tests with standard polyclonal antisera. if examined in hi tests with monoclonal antibody (mab) iib4, the virus isolates could be separated into two groups: those reacting to high titres (about two thirds of the isolates) and those negative with iib4 (titre of less ... | 1986 | 2874726 |
| variation of influenza a (h3n2) viruses isolated in the g.d.r. during 1969-1980 epidemics. | a collection of 39 influenza a virus strains of the subtype h3n2 isolated in g.d.r. and of six reference strains were analysed with regard to the antigenic structure of their surface proteins haemagglutinin (ha) and neuraminidase (na) as well as regarding their polypeptide variations. for the field strains during the drift period from spring 1969 to spring 1980 seven main variations resulted from eight polyclonal sera with the haemagglutination inhibition test, and five main variations from six ... | 1986 | 2874720 |
| characterization of the reproduction of influenza a epidemic viruses in cell cultures. | two influenza a epidemic viruses with different indices of virulence for humans have been compared with respect to their reproduction in human embryo kidney (hek), human embryo lung (hel), and chick embryo kidney (cek) cell cultures. it has been shown that the highly virulent for humans a/victoria/35/72 (h3n2) strain reproduced intensively in hek and hel cells irrespective of the inoculated dose (multiplicity of infection = 1 eid50 per cell and of 0.001 eid50 per cell, respectively). efficient i ... | 1986 | 2873731 |
| allantoic fluid protease activity during influenza virus infection. | neutral protease activity of allantoic fluid from embryonated chicken eggs was quantified during the course of influenza virus infection. antigenic subtypes of influenza a viruses selected for study were h1n1 strains pr/8/34, brazil/8/78, fm/1/47, the h3n2 strain bangkok/1/80 and the h5n9 turkey/ /ontario/66 as well as the sendai strain of parainfluenza type 1 virus. three different types of profiles of allantoic fluid proteases could be readily distinguished after infection of eggs with various ... | 1986 | 2873727 |
| the variability of genes of influenza a (h3n2) virus strains isolated in the g.d.r. during the 1970-1978 epidemic seasons. | gene variability of all influenza a virus strains (h3n2) isolated in the g.d.r. during the epidemic seasons of 1970-1978 was investigated by crna:vrna hybridization. from 1970 through 1975 a gradual smooth variability of the majority of genes and moderate heterogeneity in gene homology of the isolates were observed. from 1975 through 1977 the genome variability was more profound and the isolates differed from one another in gene homology. in 1978 the variability became less pronounced again. qua ... | 1985 | 2869657 |
| monoclonal antibodies for the rapid diagnosis of influenza a and b virus infections by immunofluorescence. | mouse monoclonal antibodies, directed against antigenic sites on influenza a and b viruses and found to be type-specific in an immunoassay, were assessed for use as diagnostic reagents in an indirect immunofluorescence assay on nasopharyngeal secretions. the influenza a antibodies were directed against nucleoprotein or matrix protein antigens and the influenza b antibodies against nucleoprotein and haemagglutinin antigens. the influenza a anti-matrix monoclonal antibody was found to give a stron ... | 1985 | 2865418 |
| subunit influenza virus vaccine grippovac se-azh (vaccination of adults). | grippovac se-azh a polytype, subunit influenza virus vaccine containing h1n1 and h3n2 influenza a virus strains and one influenza b virus strain has been tested in 80 volunteers. the trials demonstrated the harmlessness, the absence of adverse reactions, and except of the b type, the high antigenicity of vaccine preparation when administered in two injections. the optimal dose of each viral strain haemagglutinin (ha) was 15 micrograms in 0.5 ml. | 1985 | 2864825 |
| antibodies to new variants of subtype a(h3 n2) influenza virus in pigs. | following an explosive epidemic of a(h3n2) influenza among the human population of czechoslovakia in 1983, haemagglutination-inhibiting antibodies (titre range 10-640) against strains a/texas/77, a/bangkok/79 and a/philipines 2/83 were detected in 93% of sera collected from 135 pigs on three farms. only 6.6% of sera were negative. anti-neuraminidase antibodies were detected at rates of 81% and 23% in two and one of the herds, respectively. antibodies against a/rnp were demonstrated by the immuno ... | 1985 | 2860799 |
| detection of type a and b influenza viruses in clinical materials by immunoelectronmicroscopy. | direct immunoelectronmicroscopy (iem) was used for detecting influenza subtype a(h1n1), a(h3n2) and type b viruses in nasopharyngeal washings or swabs collected during three consecutive periods of enhanced influenza incidence. virus identification was performed with immune rat sera and in the case of the a(h3n2) subtype also with convalescent human sera. in all the materials examined influenza virus was demonstrated by isolation in chick embryos or by immunofluorescence in infected tissue cultur ... | 1985 | 2859758 |
| influenza in swine in belgium (1969-1986): epizootiologic aspects. | from 1984 until 1986, influenza isolates were obtained from 59 outbreaks of respiratory tract disease in belgium. in 21 of the outbreaks, h3n2-influenza virus isolates, related to the human a/port chalmers/1/73 strain were obtained. all other isolates were h1n1-influenza virus strains. the prevalence of variants of the human h3n2-influenza virus in the belgium swine population was determined by examining sow sera which had been collected between 1969 and 1984. the results of this serological stu ... | 1988 | 2851410 |
| prophylactic and therapeutic effects of murabutide in of1 mice infected with influenza a/h3n2 (a/texas/1/77) virus. | the antiviral activity of a novel biological response modifier (murabutide mdp derivative) has been investigated in 3-week-old of1 mice infected with influenza (a/texas/1/77) virus. in each experimental and control group, 10 mice were infected intranasally with a viral dose producing 50% mortality in 5 days and received murabutide via the subcutaneous or intranasal route at various doses either in a simple or in daily repeated administration. all experiments were done in triplicate. significant ... | 1988 | 2851033 |
| gamma-irradiated influenza a virus can prime for a cross-reactive and cross-protective immune response against influenza a viruses. | a-strain influenza virus a/jap (h2n2) was tested for its ability to induce cytotoxic t cells (tc) after being rendered non-infectious by either uv or gamma irradiation. gamma-irradiated virus proved to be more efficient than uv-inactivated virus in priming for a memory tc cell response or in boosting memory spleen cells in vitro. most importantly, gamma-inactivated, but not uv-inactivated, a/jap immunized animals survived lethal challenge with heterologous (a/pc(h3n2), a/wsn(h1n1)) virus as effe ... | 1988 | 2846435 |
| high-level transient expression of influenza virus proteins from a series of sv40 late and early replacement vectors. | we have constructed a collection of simian virus 40 (sv40) plasmid vectors useful for transient or constitutive expression of cdna or genomic dna in animal cells. most vectors contain several unique restriction sites downstream from the sv40 late or early promoter, and are available with or without the virus-specific splicing signals. the use of these vectors for transient expression in monkey cells of x47 (h3n2) influenza hemagglutinin (ha) and matrix protein (m1) was demonstrated. membrane-bou ... | 1988 | 2844629 |
| identification of h3n2 influenza virus isolated from pigs with respiratory problems in spain. | 1988 | 2839928 | |
| characterization of an influenza a (h3n2) virus isolated from pigs in england in 1987. | 1988 | 2838122 | |
| porcine influenza outbreak in east anglia due to influenza a virus (h3n2) | 1987 | 2832998 | |
| passive serum antibody causes temporary recovery from influenza virus infection of the nose, trachea and lung of nude mice. | balb/c normal and nude mice were infected with a non-lethal mouse-passaged a/pc/1/73 (h3n2) influenza virus in order to assess the role of t cells on the course of disease of the nose, trachea and lung. the tracheal epithelium of both mouse strains was desquamated by 3 days after infection. although normal regeneration began, nude mice never completed that regeneration whereas normal mice had fully regenerated tracheas by day 14. this failure to complete the recovery was also evident from the co ... | 1988 | 2832312 |
| isolation of human (h3n2) influenza virus and prevalence of the virus-antibody in swine. | 1987 | 2828738 | |
| outbreaks of classical swine influenza in pigs in england in 1986. | serum samples from pig herds in great britain have been examined for antibodies to influenza virus since 1968. antibodies to h3n2 virus strains have been found since 1968 and the serological data presented here suggests that h3n2 virus strains continue to persist in the pig population. an outbreak of acute respiratory disease occurred in a 400-sow unit. the outbreak was characterised by coughing, anorexia, fever, inappetence and loss of condition. the gilts and weaners were affected and the morb ... | 1987 | 2820111 |
| protection against influenza virus infection by a two-dose regimen of nasal vaccination using vaccines combined with cholera toxin b subunit. | the effectiveness of the two-dose regimen, composed of a primary intranasal inoculation of influenza a-type virus ha vaccine together with b subunit of cholera toxin (ctb) and the subsequent intranasal inoculation of vaccine alone 4 weeks later, was examined. in mice given a relatively high dose of virus a/pr/8/34 (pr-8, h1n1) ha vaccine (1.5 micrograms) both as a primary antigen with ctb (1 microgram) and as the second antigen, the secondary responses of both antiviral iga antibodies in nasal w ... | 1989 | 2815967 |
| [the change in functional activity and primary structure of the m2 protein in variants of the influenza virus resistant to remantadine and deitiforin: common and individual differences from the original strain]. | the two variants of influenza a/victoria/35/72 (h3n2) virus resistant simultaneously to remantadine, deitiforin, adapromine and amantadine were obtained while passaging the virus in presence of remantadine or deitiforin. both variants differed from the parental strain in optimal ph for hemolysis, transcriptase activity and in amino acid sequence of m2 protein. maximal hemolytic activity of the parental strain is registered at ph 5.2, for the variants cultured in the presence of remantadine or de ... | 1989 | 2811900 |
| evolutionary pathways of the pa genes of influenza a viruses. | nucleotide sequences of the pa genes of influenza a viruses, isolated from a variety of host species, were analyzed to determine the evolutionary pathways of these genes and the host specificity of the genes. results of maximum parsimony analysis of the nucleotide sequences indicate at least five lineages for the pa genes. those from human strains represent a single lineage, whereas the avian genes appear to have evolved as two lineages--one comprising genes from many kinds of birds (e.g., chick ... | 1989 | 2800339 |
| avian-to-human transmission of the pb1 gene of influenza a viruses in the 1957 and 1968 pandemics. | we determined the origin and evolutionary pathways of the pb1 genes of influenza a viruses responsible for the 1957 and 1968 human pandemics and obtained information on the variable or conserved region of the pb1 protein. the evolutionary tree constructed from nucleotide sequences suggested the following: (i) the pb1 gene of the 1957 human pandemic strain, a/singapore/1/57 (h2n2), was probably introduced from avian species and was maintained in humans until 1968; (ii) in the 1968 pandemic strain ... | 1989 | 2795713 |