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isolation of h13n2 influenza a virus from turkeys and surface water.this is the first report of the isolation of h13n2 avian influenza virus (aiv) subtype from domestic turkeys. this subtype was also isolated from nearby surface water. the observation of large numbers of gulls in close association with turkeys on range before the virus isolations suggests that this virus subtype was transmitted from gulls to range turkeys. turkey flocks infected by this virus subtype did not show any clinical signs of the disease, although seroconversion did occur. the h13n2 iso ...19911838479
positive darwinian evolution in human influenza a viruses.we earlier suggested that type a human influenza virus genes undergo positive darwinian selection through immune surveillance. this requires more favorable amino acid replacements fixed in antigenic sites among the surviving lineages than among the extinct lineages. we now show that viral hemagglutinins fix proportionately more amino acid replacements in antigenic sites in the trunk of the evolutionary tree (survivors) than in the branches (nonsurvivors), demonstrating that type a human influenz ...19911840695
influenza a virus-induced otitis media and mucociliary dysfunction in the guinea pig.there is much epidemiologic, clinical and laboratory evidence that viral infection is involved in otitis media with effusion (ome). however, few studies have demonstrated any direct influence of viruses on the tubotympanum. the purpose of this study was to establish the effect of influenza a virus having invaded the tubotympanum and so elucidate the possible mechanism by which this virus contributes to the pathogenesis of ome. eighty guinea pigs with normal otoscopic findings were inoculated wit ...19911842862
[serological investigation of influenza type a and b in university students, brazil].wide serological prevalence of influenza a and b was verified by the serological survey covering 200 students of the university of s. paulo during the 1984-1985 period. the humoral antibodies were detected by the single radial haemolysis technique, whose arithmetic titres averages were greater for both subtypes, (h1n1) and (h3n2) of the influenza a virus strains recently isolated from the population. however, the situation of this type b virus was not the same as that of type a seeing that the b ...19911843236
immunization with subunit human immunodeficiency virus vaccine generates stronger t helper cell immunity than natural infection.healthy, human immunodeficiency virus seronegative (hiv-) volunteers were multiply immunized with a recombinant gp160 (rgp160) candidate acquired immunodeficiency syndrome (aids) vaccine. peripheral blood lymphocytes from volunteers immunized with 40 micrograms or with 80 micrograms (two volunteers per group) of rgp160, as well as from control donors, were tested for t helper (th) cell function either prior to immunization, 8 to 12 months after the third immunization, or 2 to 5 months after the ...19911845391
swine influenza virus infections. transmission from ill pigs to humans at a wisconsin agricultural fair and subsequent probable person-to-person transmission.in september 1988, a previously healthy 32-year-old pregnant woman was hospitalized for pneumonia and died 8 days later. the only pathogen detected was an influenza virus antigenically related to the swine influenza virus (siv). four days before illness onset, the patient visited a county fair swine exhibition where there was widespread influenzalike illness among the swine. to detect other persons who were possibly infected by contact with the ill swine, we measured serum siv hemagglutination-i ...19911845913
structural features influencing hemagglutinin cleavability in a human influenza a virus.the cleavability of the hemagglutinin (ha) molecule is related to the virulence of avian influenza a viruses, but its influence on human influenza virus strains is unknown. two structural features are involved in the cleavage of avian influenza a virus has: a series of basic amino acids at the cleavage site and an oligosaccharide side chain in the near vicinity. the importance of these properties in the cleavability of a human influenza a virus (a/aichi/2/68) ha was investigated by using mutants ...19911847449
influenza viral infection of swine in the united states 1988-1989.swine are an animal reservoir for influenza viruses capable of causing disease in humans. a serological survey in 1988-1989 demonstrates that subtype h1 influenza viruses continue to circulate at high frequency among swine in the north-central u.s.a. (average 51% incidence). subtype h3 viruses antigenically similar to current human h3 viruses are circulating at low frequency (average 1.1%), particularly in the southeast u.s.a.19911848066
influenza vaccination in the prevention of acute otitis media in children.we studied a new approach to the prevention of acute otitis media through the administration of influenza vaccine to 187 day-care center children aged 1 to 3 years before the influenza a epidemic of 1988-1989. the control group consisted of 187 unvaccinated children of similar age and background. during the 6-week study period, influenza a infection was diagnosed in five (3%) of 187 vaccinees and in 29 (16%) of 187 controls. acute otitis media developed in three (60%) of five vaccinees with an i ...19911849344
in vitro incubation with influenza virus primes human polymorphonuclear leukocyte generation of superoxide.viral respiratory illnesses exacerbate asthma, increase airway responsiveness, and enhance the frequency of late asthmatic reactions. a number of mechanisms have been identified to explain how respiratory viral illnesses provoke wheezing, including enhanced inflammatory activity of leukocytes. to further understand how respiratory virus-caused illnesses promote leukocyte-dependent airway injury, the following study evaluated the effect of an in vitro incubation of influenza a virus on human poly ...19911849727
delay time for influenza virus hemagglutinin-induced membrane fusion depends on hemagglutinin surface density.we have studied the kinetics of low-ph-induced fusion between erythrocyte membranes and membranes containing influenza virus hemagglutinin by using assays based on the fluorescence dequenching of the lipophilic dye octadecylrhodamine. stopped-flow mixing and fast data acquisition have been used to monitor the early stages of influenza virus fusion. we have compared this with the kinetics observed for fusion of an nih 3t3 cell line, transformed with bovine papillomavirus, which constitutively exp ...19911850019
reassessment of the association between guillain-barré syndrome and receipt of swine influenza vaccine in 1976-1977: results of a two-state study. expert neurology group.although the original centers for disease control study of the relation between a/new jersey/8/76 (swine flu) vaccine and guillain-barré syndrome (polyradiculoneuritis) demonstrated a statistical association and suggested a causal relation between the two events, controversy has persisted. to reassess this association, the authors obtained medical records of all previously reported adult patients with guillain-barré syndrome in michigan and minnesota from october 1, 1976 through january 31, 1977 ...19911851395
expression of avian influenza virus hemagglutinin by recombinant fowlpox virus.a vaccine strain of fowlpox virus (fpv) was genetically engineered to produce avian influenza virus hemagglutinin (ha). this was accomplished by inserting a cdna copy of the avian influenza virus ha gene, which was regulated by a vaccinia virus promoter, into the fpv thymidine kinase (tk) gene. two types of recombinant viruses, differing only in the orientation of the ha gene relative to an adjacent foreign gene (lacz), were created. following preliminary identification of fpv recombinants based ...19911851414
binding of viral glycoprotein with trypsin and its relation to virulency. ii. comparison between bovine and streptomyces griseus trypsins.the two step nature of the binding reaction between trypsin and viral glycoproteins was further investigated using two types of trypsin, bovine trypsin and streptomyces griseus trypsin. the experimental results were explained by the van der waals energy operating in the second step, suggesting that the conformational aspects, in addition to the electrostatic nature, of the interacting peptides are decisive in this specific process.19911851673
localization of the influenza virus nucleoprotein: cell-associated and extracellular non-virion forms.both the supernatant of influenza virus-infected chick embryo cells and allantoic fluid containing influenza virus were shown to contain non-virion nucleoprotein (np), which reacted readily with anti-np monoclonal antibodies. adsorption onto erythrocytes and centrifugation at 70,000 g for 2 h resulted in the removal of about 20% of the extracellular np, whereas centrifugation at 100,000 g for 4 h eliminated about 50%, and practically all [3h]uridine-labelled virions. these results suggest that o ...19911856696
[use of a multivariate analysis method for determining the interconnection of genetic markers with gene clusters and solution of taxonomy problems for the recombinant influenza a virus model].the collection of influenza a viral recombinants has been studied for determining interconnection of the definite genetical marker (pneumovirulence for mice) with genes constellation by the technique of image identification. pneumovirulence is found to be defined by correlation of polymerase complex m-, ns- and na-genes. the data on na influence on pneumovirulence were obtained for the first time, the phenomenon being found only with the use of image identification technique. the used methods of ...19911857374
[detection of influenza virus nucleoprotein on the surface of infected cells and in free nonvirion form].the inner viral nucleoprotein synthesized de novo is shown to be exposed on the surface of the chicken embryo infected with influenza virus. the kinetics of the nucleoprotein located on the surface does not correlate with the kinetics of cell destruction. in culture or allantois virus containing liquids the large number of extracellular viral nucleoprotein prone to antinucleoprotein monoclonal antibodies was found. the accumulation of this nucleoprotein occurs in the period when cell destruction ...19911857375
[the sensitivity of a number of cell cultures to different types of influenza viruses and their reassortants].the study of reproductive activity of human and animal influenza a, b, and c viruses as well as influenza a virus reassortants in some cell cultures allowed one to determine the range of cells susceptible for each type (subtype) of the viruses. differences in the range of cells were demonstrated for different strains of influenza viruses of the same antigenic subtype. it was noted that reassortants of influenza a viruses with the same hemagglutinin subtypes as the parental strains had a wider ra ...19911858352
[a comparative study of monoclonal and monospecific antibodies in determining the immunodominant antigenic sites of influenza virus a (h3n2) hemagglutinin].comparative studies of monospecific (msa) and monoclonal (mca) antibodies showed msa to detect three non-overlapping immunodominant sites on the surface of hemagglutinin (ha) molecule whereas mca established more subtle differences in ha antigenic structure on the level of epitopes with different immunological significance. the activity of msa and mca differed in various tests. while mca were more active in hi and eia tests, msa had a higher neutralizing activity, reducing the infectious virus t ...19911858361
influence of trifluoperazine on the late stage of influenza virus infection in mdck cells.we investigated the influence of the anticalmodulin drug, trifluoperazine (tfp) on influenza virus growth in mdck cells. the inhibitory effect of tfp on virus growth was observed even when tfp was added at a late stage of infection. this inhibitory effect was concentration-dependent in the concentration range of 20-35 microm. at 35 microm, tfp caused a complete alteration in the distribution pattern of hemagglutinin (ha), concomitant with a decrease in the appearance of ha on the cell surface. a ...19911859203
epidemiology of acute respiratory infections in children of developing countries.acute respiratory infections cause four and a half million deaths among children every year, the overwhelming majority occurring in developing countries. pneumonia unassociated with measles causes 70% of these deaths; post-measles pneumonia, 15%; pertussis, 10%; and bronchiolitis and croup syndromes, 5%. both bacterial and viral pathogens are responsible for these deaths. the most important bacterial agents are streptococcus pneumoniae, haemophilus influenzae, and staphylococcus aureus. the data ...19911862276
[hyaluronic acid and hyaluronidase in influenza].hyaluronidase and hyaluronic acid activities are markedly changed in influenza, these changes directly depending on the severity of the inflammatory process that depends on the presence of bacterial complications in influenza. the authors' findings correlate with the literature data on the blood mucolytic system status in various infectious diseases. the results recommend measurements of hyaluronidase and hyaluronic acid activities as an additional test for the early diagnosis of influenza compl ...19911862370
failure to obtain drug-resistant variants of influenza virus after treatment with inhibiting doses of 3-deazaadenosine and h7.3-deazaadenosine and h7 specifically inhibit influenza virus replication under conditions at which they have no effect on other tested rna viruses. this effect can be significantly potentiated by concomitant application of both compounds. even under the most stringent conditions we failed to obtain any drug resistant variants. a possible explanation for this failure is that these compounds presumably do not act on a viral component like amantadine which was used as a control, but they interfere ...19911863219
replication of avian influenza viruses in humans.volunteers inoculated with avian influenza viruses belonging to subtypes currently circulating in humans (h1n1 and h3n2) were largely refractory to infection. however 11 out of 40 volunteers inoculated with the avian subtypes, h4n8, h6n1, and h10n7, shed virus and had mild clinical symptoms: they did not produce a detectable antibody response. this was presumably because virus multiplication was limited and insufficient to stimulate a detectable primary immune response. avian influenza viruses c ...19911863223
spot-scan imaging of microcrystals of an influenza neuraminidase-antibody fragment complex.electron micrographs of two-dimensional microcrystals of a complex of an avian influenza virus neuraminidase and an antibody fab fragment, termed 32/3, have been recorded using the spot-scan method of imaging. the crystals have a large unit cell (159.5 a x 159.5 a x 130.5 a) and a high solvent content (approximately 71% by volume) and are a challenging specimen for testing the spot-scan methodology. crystalline order was preserved to beyond 4 a resolution as demonstrated by electron diffraction, ...19911866839
[immunochemical characteristics of the population structure of antibody-producing cells in experimental influenza].the authors presented the results of population study of specific igg-antibody-forming cells (afc) in the pool of mice splenocytes performed in the time-course of simulated influenza with the help of experimental mathematical approach which permitted making a detailed observation of the functional structure of the population and analysing the changes in the spectrum of the afc subpopulations in the time-course of viral disease. mathematical simulation of the main stage of immunopointed identific ...19911866979
[formation of target cells in the immunocompetent organ (spleen) of mice with experimental infection caused by influenza a viruses with various properties].the article presents the data on the time-course of formation of ++virus-pecific target-cells in spleens of mice infected with various types of influenza caused by a virulent viral strain and its avirulent ts-mutation. it was demonstrated that these target-cells occurred in all studied patterns of infection. their formation turned to be of cyclic character, dose-dependent and closely related with the formation of all known mechanisms of specific and nonspecific cellular defense. the presentation ...19911866981
[natural killer cells and their protective role in viral infections]. 19911866982
[changes in the intracellular localization of viral antigens in influenza].the authors studied intracellular location of the viral structures in the lung tissue in the acute period of infection (on the 3rd-6th after inoculation) and on the 28th day when the infectious virus failed to be detected. it was stated that on the 3rd and 6th day after the inoculation viral antigens were equally distributed between cytoplasmic and membraneous fractions. the 28th day demonstrated the presence of the antigens in cytoplasma and their absence in the cellular membranes of the lung. ...19911866984
[study of biological equilibrium in the body in viral infection of different degree of severity (on the model of influenza)].the authors made a comparative analysis of the contribution to the outcome of the disease by realization of information of viral genome and host responses in the time-course of simulated lethal and nonlethal mice influenza. they studied the effect of ionol, pathogenetic antioxidant, prevention and depicted absolutely new features of the diseases severity and outlined possible points of effective drug application. the suggested scheme of the time-course measurement of viral involvement of the hos ...19911866985
[post-stress disorders of resistance of mice to recurrent infection by homologous influenza virus].a decrease in the mouse resistance to reinfection by influenza virus under the effect of immobilization stress was depicted. violation in the formation of a long-term resistance to a repeated disease ran in the presence of the high levels of circulating anti-influenza antibodies and not ++always correlated with a post-stress impairment of the formation of antigen-reactive clones of cells in the spleen of primarily infected mice. prophylactic administration of ionol which prevented a post-stress ...19911866988
[functional activity of antibody-producing cells in mice with experimental influenza].the paper presents the findings on the functional activity of specific antibody-forming cells (afc) in the time-course of the primary influenza infection in mice. the concept of afc functional activity is validated. studying of the afc population in the pool of splenocytes based on the analysis of functional activity permitted one to make a detailed description of specific afc, and make a series of conclusions of the technique of afc identification, reveal the changes in the structure of the vir ...19911866992
correlation of amino acid residues in the m1 and m2 proteins of influenza virus with high yielding properties.the ability of influenza a viruses to replicate to high titer in the allantoic sac of the chicken embryo has been mapped to the matrix protein gene (rna 7). because influenza a/wsn/33 (h1n1) virus grows poorly in this host but contains a matrix protein gene with a sequence similar to sequences from viruses that grow well in eggs, we derived a single gene reassortant containing only the m gene from a/wsn/33 (h1n1) in a background of the other 7 rna segments from a/philippines/2/82 (h3n2) (a low y ...19911867007
heterogeneous forms of polymerase proteins exist in influenza a virus-infected cells.in influenza virus-infected cells a virus coded polymerase that consists of three polypeptide subunits, namely pb1, pb2 and pa, mediates both transcription and replication. radioimmunoprecipitation with monospecific antisera to each of the polymerase proteins revealed additional forms of pb1 and pa proteins in infected cells. pa antiserum detected two additional proteins of 62k and 60k and pb1 antiserum recognized two additional proteins of 85k and 70k. further investigation was carried out on t ...19911867008
detection of influenza viruses in throat swab by using polymerase chain reaction.an assay protocol based on exploiting the polymerase chain reaction (pcr) for the direct detection of influenza virus in throat swab is described. by use of the mixture of h1 and h3 primers, it was possible to determine the subtype of the influenza a viruses simultaneously. no visible band was detected after pcr of influenza b or a (h2n2) viruses with a pair of h1 or h3 primers. the dilution experiment showed that the influenza viruses, as few as 1.3-6 plaque-forming units, were sufficient for d ...19911870441
[rapid diagnosis of influenza virus infections from nasopharyngeal secretions].since virus isolation consumes a lot of work and time, and virus specific antibodies are not detectable before several days after the onset of illness we developed an enzyme immunoassay (elisa) for the detection of influenza a and influenza b virus antigen in nasopharyngeal specimens (nps). this test permits antigen detection within four hours. this elisa was tested with 119 nps from children, most of these between 1-12 years old. virus isolation in mdck-cells served as control. a total of 67 in ...19911870599
deacylation of the hemagglutinin of influenza a/aichi/2/68 has no effect on membrane fusion properties.the effects of deacylating the h3 influenza hemagglutinin (ha) on its membrane fusion activity were investigated. chemical deacylation caused no change in the ability of ha to fuse liposomes in vitro. site-specific mutagenesis of the three cysteine residues in the cytoplasmic tail singly, or in combination, showed that all three were palmitoylated. substitution of one, two, or all three cysteines with serine and subsequent lack of palmitoylation at mutated sites had no effect on the ph of the co ...19911871979
reassortants with equine 1 (h7n7) influenza virus hemagglutinin in an avian influenza virus genetic background are pathogenic in chickens.reassortants possessing the hemagglutinin (ha) gene from a/equine/london/1416/73 (h7n7) [eq/lond] and five or more genes from a/chicken/pennsylvania/1370/83 (h5n2) [ck/penn] were lethal in chickens. this result demonstrates that horses can maintain influenza viruses whose has are capable of promoting virulence. thus, reassortment of equine and avian influenza virus genes could generate viruses that might be lethal in domestic poultry.19911871981
programmed antigenic stimulation: kinetics of the immune response to challenge infections of mice primed with influenza inactivated whole virus or neuraminidase vaccine.mice were immunized with either inactivated whole virus influenza a (h3n2) virus (wv) vaccine or with purified n2 neuraminidase (na) vaccine then challenged with mouse-adapted homologous infective virus at intervals of 1-141 days later in order to ascertain the optimal vaccine-infection interval for induction of resistance to subsequent infection. measured by serological or infection suppressing response, this interval was 15 days for both vaccines. maximal reduction in pulmonary virus replicati ...19911872017
unexplained fluctuations in the risk for schizophrenia by month and year of birth.variation in their year and month of birth was studied in the 13,661 schizophrenics born between 1914 and 1960 known to the scottish psychiatric case register. year-to-year fluctuations in the number of schizophrenics per 10,000 live births were outside chance limits. so were month-to-month fluctuations between january 1932 and december 1960, and this was largely due to fluctuations in the numbers of schizophrenics born in february, march, april and may. time-lagged correlations with mean monthl ...19911873628
a comparison of direct immunofluorescence, shell vial culture, and conventional cell culture for the rapid detection of influenza a and b.direct immunofluorescence (fa) and shell vial contrifugation cultures (svcs) were compared with conventional tube cultures for the rapid detection of influenza a and b by using a commercial antibody. of the 439 specimens tested, 82 were positive by conventional culture (cc). the direct smear prepared from pelleted cells or direct swab material exhibited positive fluorescence in only seven (8.5%) of these cases, whereas the svc was positive in 30 (37%). the svc method detected 12 additional posit ...19911873971
fusion of influenza virions with a planar lipid membrane detected by video fluorescence microscopy.the fusion of individual influenza virions with a planar phospholipid membrane was detected by fluorescence video microscopy. virion envelopes were loaded with the lipophilic fluorescent marker octadecylrhodamine b (r18) to a density at which the fluorescence of the probe was self-quenched. labeled virions were ejected toward the planar membrane from a micropipette in a custom-built video fluorescence microscope. once a virion fused with the planar membrane, the marker was free to diffuse, and i ...19911875185
the role of n-acetylneuraminic (sialic) acid in the ph dependence of influenza virion fusion with planar phospholipid membranes.it is known that fusion of influenza virus to host cell membranes is strongly promoted by acidic ph. we have determined conditions required to obtain ph-dependent fusion of influenza virus to planar bilayer membranes. the rate of viral fusion was determined from the flash rate of r18-labeled virions delivered to the surface of the planar membrane by pressure-ejection from a pipette. for a bilayer formed only of phospholipids and cholesterol, the fusion rate was independent of ph and unaffected b ...19911875186
molecular evidence for a role of domestic ducks in the introduction of avian h3 influenza viruses to pigs in southern china, where the a/hong kong/68 (h3n2) strain emerged.the haemagglutinins (has) of five h3 influenza a viruses isolated from domestic ducks and one from a goose in southern china were analysed antigenically and genetically. the patterns of reactivity of two of the duck viruses and the goose virus with a panel of monoclonal antibodies to 10 different epitopes on the h3 ha were similar to those of influenza viruses isolated from wild ducks and pigs, as well as those of the earliest human h3 viruses. the other three isolates from domestic ducks were d ...19911875195
replication of influenza a viruses in an avian macrophage cell line.the virulent avian influenza virus a/ty/ont/7732/66 (h5n9) (ty/ont) causes severe destruction of the lymphoid cells in infected birds. previous studies have suggested that viral infection of macrophages may be involved. however, ty/ont failed to replicate productively in primary cultures of chicken macrophages. therefore, in an effort to develop an in vitro system for our studies, we examined the susceptibility of an avian macrophage cell line, hd11, to ty/ont. we found that ty/ont replicated in ...19911875196
hydrophobized antiviral antibodies and antisense oligonucleotides.a method of suppressing virus reproduction in cells has been proposed. the approach consists of affecting the cells with antiviral antibodies artificially hydrophobized with fatty acid residues. reproduction of influenza viruses in mdck cells and respiratory-synticial virus in hela cells was used as a model to demonstrate that poly- and monoclonal antibodies, modified by 1 or 2 stearic acid residues, are potent, unlike the non-modified antibodies, at inhibiting viral reproduction. the observed p ...19911877397
amantadine inhibits an early, m2 protein-dependent event in the replication cycle of avian influenza (h7) viruses.analysis of the effects of amantadine during a single cycle of replication of a/fpv/rostock virus in vitro showed that, as with other influenza a viruses, an m2 protein-dependent step early in infection was inhibited. no effect was observed on later steps in replication under the conditions used.19911877888
amantadine for influenza a. 19911878041
[immunosuppression induced by respiratory viruses (influenza virus, adenovirus) in mice].the influence of respiratory viruses (adenovirus, influenza virus) on humoral immune response to heterologous t-dependent and t-independent antigens was studied. it was shown that inoculation of mice by the influenza virus (a/pr8/34-a/pr/8) 3 days before sheep red blood cells administration led to the inhibition of antibody forming cell (afc) and immunoglobulin, forming cell (ifc) increase on 69% and 59% respectively. adenovirus type 6 induced the similar suppression of afc and ifc formation. th ...19911878568
fluvirucins a1, a2, b1, b2, b3, b4 and b5, new antibiotics active against influenza a virus. i. production, isolation, chemical properties and biological activities.five unidentified actinomycete strains produced a series of novel antiviral antibiotics which have a unique 2,6-dialkyl-10-ethyl-3(or 9)-hydroxy-13-tridecanelactam nucleus substituted with 3-amino-3,6-dideoxy-l-talose or 3-amino-3,6-dideoxy-l-mannose(l-mycosamine). the antibiotic components exhibited potent inhibitory activity against influenza virus type a victoria strain infection in madin darby canine kidney cells by the cytopathic effect reduction assay.19911880063
fluvirucins a1, a2, b1, b2, b3, b4 and b5, new antibiotics active against influenza a virus. ii. structure determination.a series of structurally related antiviral antibiotics, fluvirucins a1, a2, b1, b2, b3, b4 and b5 have been isolated from the fermentation broths of five unidentified actinomycete isolates. based on spectroscopic analysis, partial degradation experiments and 13c-enriched acetic acid-fed biosynthetic studies, their structures were elucidated to be 2.6,10-trialkyl-3(or 9)-aminoglycosyl-13-tridecanelactams.19911880064
fluvirucins a1, a2, b1, b2, b3, b4 and b5, new antibiotics active against influenza a virus. iii. the stereochemistry and absolute configuration of fluvirucin a1.fluvirucin a1 was established as (2r,3s,6r, 10s)-3-[(3-amino-3,6-dideoxy-alpha-l-talopyranosyl)-oxy]-2,6-dimethyl-10 -ethyl-13-tridecanelactam by chemical, spectroscopic, and x-ray crystallographic analyses.19911880065
[influenza virus proteins: preparation of a soluble m1 polypeptide by means of a stepwise deproteination of virions].layer by layer uncoating of influenza a and b viruses with non-ionic detergent (np-40) at fixed ph was developed. treatment of virions with np-40 at neutral or alkaline ph solubilized the lipoprotein envelope and the surface glycopolypeptides ha1 and ha2, but the internal core structures containing matrix protein m1 remained. exposition of the cores in acidic media (ph 4,5 and lower) selectively solubilized protein m1 and released viral ribonucleoprotein (rnp). the resulting m1 sedimented in a g ...19911881394
differences in sensitivity in haemagglutinin inhibition assays between a/equine/h3n8 viruses isolated in eggs and mdck cells are linked to cleavage of the haemagglutinin molecule.two primary isolates of a/equine/h3n8 viruses were obtained in embryonated hens' eggs and in madin-darby canine kidney (mdck) cells. viruses isolated in mdck cells were significantly more sensitive as antigens in haemagglutination inhibition (hi) tests. this sensitivity appeared to be primarily linked to the extent of cleavage of the haemagglutinin molecule.19911882503
[the selection of cold-adapted variants of the influenza viruses h1n1 and h3n2 and their antigenic and genetic characteristics].as a result of serial passages (42 passages) at low temperatures (26 degrees--28 degrees c) of two influenza h1n1 and h3n2 virus strains stable cold-adapted (ca) variants were produced. investigations of them showed the ca a/ussr/03/84 (h1n1) variant to have ts-mutations in genes 1, 2, 4, 5, 7, and 8 and the ca a/ussr/215/79 (h3n2) to have ts-mutations in genes 1, 3, 4, 5, 7 and 8. these ca-variants may be recommended as attenuation donors to be used in recombination experiments with epidemic in ...19911882517
[the action of uv irradiation on the reproduction of the influenza a virus and on virion rna-polymerase activity]. 19911882524
[the use of the immunofluorescence method for the rapid diagnosis of influenza during 1968-1988 in bulgaria]. 19911882525
[mutations in the genes coding for hemagglutinin and neuraminidase in cold-adapted variants of the influenza virus a/leningrad/134/57 (h2n2)].an analysis of ts-mutations in the genomes of native and cold-adapted variants of influenza a/leningrad/134/57 (h2n2) virus based on the use of fowl plague virus ts mutants was carried out. the recombination test was done by the conventional method in chick embryo fibroblast culture (genes pb2, pb1, pa, np, na, m and ns) or cell systems permissive for reproduction of human influenza virus (gene ha). the cold-adapted strain a/len/17 used for preparation of live influenza vaccine (liv) for adults ...19911882532
[the possibility of long-term prognosis in influenza a pandemics].on the basis of the analysis of the most significant influenza a pandemics over the period of 300 years, compared with periodic long-term changes in the climate and the cycles of solar activity, regularities in the manifestation of the biorhythms of the epidemic activity of influenza a virus have been established. the prognosis of pandemics for near and remote future is proposed.19911882623
[the immunomorphological characteristics of the appendix in a viral-bacterial lesion in children with appendicitis].the characteristics of viral-bacterial lesion in the appendix of children with appendicitis are given by means of histologic, histochemical, immunomorphological and morphometric methods. antigens of influenza viruses a, b, c, entero-, adeno- and paramyxoviruses were observed among which influenza c was found significantly more frequently (64.1%). viral infection in the majority of cases (79.5%) was found in the association with opportunistic flora, more frequently with e. coli, and less r. aerug ...19911883273
influenza a virus infects macrophages and stimulates release of tumor necrosis factor-alpha.the clinical picture of influenza a virus infections indicates that release of tumor necrosis factor-alpha (tnf-alpha) may be involved. in the present study we exposed the murine macrophage line pu5-1.8 to influenza a virus and observed a productive infection which was followed by subsequent cell death. infection of macrophages was accompanied by tnf-alpha mrna accumulation and tnf-alpha release. tnf-alpha production could only be induced by live virus whereas interferon release was also stimula ...19911883518
effect of rimantadine on the immune response to influenza a infections.the effects of rimantadine on lymphocyte responses to mitogens con-a and pha, natural killer cell activity, and the development of serum and local antibodies were studied during an epidemic outbreak of influenza a (h3n2). twenty-three families consisting of 38 adults and 46 children had a member who developed a flu-like illness and were randomly assigned to receive placebo or rimantadine either as treatment or post exposure prophylaxis. nasal washings for virus isolation and igg and iga determin ...19911885945
principles of selective inactivation of viral genome. vi. inactivation of the infectivity of the influenza virus by the action of beta-propiolactone.the kinetics of inactivation of the infectivity of the influenza virus by beta-propiolactone have been studied. rate constants have been determined for inactivation of the a/leningrad/385 (h3n2) and b/leningrad/489/80 influenza virus under the action of beta-propiolactone on a virus-containing allantoic fluid and on a purified viral suspension. the data obtained allow calculation of the time required for inactivation of the influenza virus infectivity to a given extent in virus-containing soluti ...19911887669
[nucleic acid molecular hybridization as a method for the laboratory diagnosis of influenza: its potentials and prospects].experiments carried out by the present moment in a number of laboratories indicate that the method of molecular hybridization (mh) has great diagnostic potential. sufficient methodological mastery of the reaction of radioactively labeled dna probes with rna samples applied into a polymer membrane and good supply of commercially available materials make it possible to recommend this method for use in reference laboratories at specialized diagnostic centers. hybridization should be used in combina ...19911887705
[the immunomodulating action of the surface antigens of the influenza a virus in experimental staphylococcal infection].the results of the study of influenza a virus surface antigens, hemagglutinin and neuraminidase, in the induction of nonspecific immunomodulation and protection from acute pulmonary staphylococcal infection have been studied. protective effect, the cell composition of bronchoalveolar lavage fluid depend on the serological subtypes of surface antigens used for intranasal immunization and the infective dose of staphylococci.19911887712
inhibition of influenza a virus replication by a kanamycin derivative.we studied the antiviral activity and the mechanism of action of a new antiviral agent and kanamycin derivative, 1-n-eicosanoyl-3"-n-trifluoroacetyl kanamycin a (etka), against influenza a virus. from yield reduction assays with vero cells, etka showed a significant antiviral activity with negligible cytotoxic effect. in the presence of 20 micrograms/ml of etka at which vero cell growth was not inhibited, virus titer was suppressed to 11.2% of control, and at 100 micrograms/ml virus production w ...19911888175
influenza virus strain identification for the 1990-1991 influenza season. 19911889092
detection of toxic viral-associated double-stranded rna (dsrna) in influenza-infected lung.while many of the molecular events in viral replication are well studied, the molecular mechanisms by which viral infections trigger such constitutional symptoms as fever and 'malaise' are unknown. the hypothesis that these viral constitutional symptoms can be triggered by the toxic action of dsrna associated with viral replication was investigated. total lung rna from mice acutely infected with pr8 influenza virus, but not from sham-infected mice, was shown to induce fever and altered sleep (ex ...19911890949
[the anomalous isoelectric properties of influenza virus matrix protein m1].the isoelectric point (pi) values of matrix protein m1 of influenza a, b, and c viruses, calculated theoretically on the basis of its primary structure, were found to be about 10.0. however, experimental pi determination by electrofocusing in ampholyte-containing polyacrylamide gel showed it to be 5.0 for m1 protein isolated from a/wsn/33 (h1n1) and a/aichi/2/68 (h3n2) viruses by mild deproteinization with nonionic detergents. this marked discrepancy between experimental and theoretical pi value ...19911891873
[the role of antibody functional activity in the protection of people against influenza].indices of the functional activity of specific serum antibodies (ifaa) before and after outbreaks of influenza a (h3n2) and b were determined in 164 subjects of 18-20 years of age from the military communities observed in 1987-1988. the ifaa were calculated on the basis of kinetic hi tests followed by computer processing according to the program developed by the authors. the ifaa were found to indicate the protection of human subjects against influenza, reflecting the state of resistance to infl ...19911891874
[the protective effect of hemagglutinin-specific monoclonal antibodies in experimental influenza infection].experiments in mice showed a high protective effect of monoclonal antibodies (mca) to influenza a/krasnodar/101/59 (h2n2) virus hemagglutinin, possessing neutralizing activity in ovo. a 100% protective effect was observed upon intranasal administration of mca kp/101-3 48 hours before infection, and 90% effect upon administration of mca 96 hours before infection. a 100% therapeutic effect was observed upon intranasal administration of mca kp/101-3 less than 24 hours postinfection and 70% therapeu ...19911891875
[detection in the structure of influenza viral proteins of sequences similar to vasoactive intestinal peptide].the paper presents the results on the influenza virus proteins (only ha, m and ns) contained in the amino acid sequence regions similar to that of the vip. these data may be important as there is similarity in pathological reactions between vip and influenza virus.19911893136
a cluster of mutations in hla-a2 alpha 2 helix abolishes peptide recognition by t cells.in order to investigate the regions of hla-a2 that control peptide-specific cytotoxic t lymphocyte (ctl) recognition, 37 hla-a2 genes coding for 50 point mutations that span the alpha 2 helix were synthesized by the technique of saturation mutagenesis. twenty-nine of these genes, which code for 41 point mutations, were transfected into c1r cells and used as targets in cytotoxicity assays, in the presence of influenza-a matrix peptide 58-68 with specific ctl as effectors. all the transfectants we ...19911894308
evolutionary analysis of the influenza a virus m gene with comparison of the m1 and m2 proteins.phylogenetic analysis of 42 membrane protein (m) genes of influenza a viruses from a variety of hosts and geographic locations showed that these genes have evolved into at least four major host-related lineages: (i) a/equine/prague/56, which has the most divergent m gene; (ii) a lineage containing only h13 gull viruses; (iii) a lineage containing both human and classical swine viruses; and (iv) an avian lineage subdivided into north american avian viruses (including recent equine viruses) and ol ...19911895397
infection of cultured human airway epithelial cells by influenza a virus.the lack of an adequate in vitro model has hampered study of the cellular basis by which influenza a virus causes disease in the human airway. we report in vitro infection of human airway epithelial cells by influenza a virus. fetal and adult human tracheal and bronchial epithelial cells cultured from explants and sv40 transformed adult human tracheal epithelial cells were exposed to a recently isolated strain of influenza a virus (h1n1) and a laboratory passaged strain (wsn) of influenza a viru ...19911895875
[the role of polymerase protein genes of influenza a virus in the transition from the early to late stage of replication].regulation of influenza virus rna replication was studied with the use of a/fpv/rostock/34 strain ts-mutants. mutants c44, c15, c45 possessing the ts-defects in the pb2, pb1 and pa genes respectively were used for the infection of chick embryo cultured cells and h-uridine-labelled nucleocapsid-associated rna was analysed in polyacrylamide gel electrophoresis to assess the kinetics of vrna synthesis. a typical early-late transition of the pattern of vrna synthesis was observed in the cells infect ...19911896057
principles of selective inactivation of viral genome. vii. some peculiarities in determination of viral suspension infectivity during inactivation by chemical agents.when the infectivity of the influenza virus is determined by means of titration on chicken embryos, calculating the infection titre according to reed and muench, the course of inactivation with beta-propiolactone shows an anomaly - the fraction of infected embryos in a batch initially increases and then decreases as the degree of dilution of the virus-containing sample is increased. this anomaly occurs because a slight dilution lowers the agent concentration insufficiently so that inactivation g ...19911897304
characterization of the attenuating m and np gene segments of the avian influenza a/mallard/78 virus during in vitro production of avian-human reassortant vaccine viruses and after replication in humans and primates.a unique requirement for live attenuated reassortant influenza vaccines is the need to generate new reassortant vaccine viruses with the appearance of each new antigenic variant. thus, the attenuation phenotype conferred by the attenuated donor influenza virus must remain genetically stable during the generation of each new reassortant vaccine virus. in this study we used nucleotide sequence analysis to evaluate the genetic stability of the attenuating m and np genes of the avian influenza a/mal ...19911897305
a shared kappa reciprocal fragment and a high frequency of secondary jk5 rearrangements among influenza hemagglutinin specific b cell hybridomas.ig kappa-chain gene rearrangement results in the displacement or loss of the dna immediately 5' of jk. this retained dna is found on a different size fragment than in the germline (a reciprocal fragment), and contains the reciprocal joint of rearranged vk and jk genes, the back-to-back fusion of the heptamer/nonamer recombination signals. b cells of independent origin rarely have reciprocal fragments of the same size. however, we report that 9 of 15 b cell hybridomas of independent origin have r ...19911898606
immune recognition of hla molecules downmodulates cd8 expression on cytotoxic t lymphocytes.an hla-a2+ cytotoxic t lymphocyte (ctl) line restricted by hla-a2 in recognition of an influenza b virus nucleoprotein (bnp) peptide uses the cd8 coreceptor in the recognition of this viral peptide. incubation of these ctl with bnp peptide in the absence of antigen-presenting cells downmodulates cd8 alpha and cd8 beta expression and reduces their ability to lyse target cells without inducing self-lysis. cd8 downmodulation was dependent on peptide concentration, time of exposure, and t cell recep ...19911898661
immunogenic peptides of influenza virus subtype n1 neuraminidase identify a t-cell determinant used in class ii major histocompatibility complex-restricted responses to infectious virus.six nonoverlapping peptides of the neuraminidase (na) glycoprotein of influenza virus a/puerto rico/8/34 (h1n1) (pr8 virus) were found to be immunogenic for proliferating t cells when injected into balb/c mice in freund adjuvant. t cells elicited by peptide immunization could recognize pr8 virus in vitro. however, only one of these peptides, corresponding to residues 79 to 93 of na (na 79-93), was able to restimulate t cells of mice immunized with infectious virus. t cells that recognized this p ...19911898970
serum adenosine deaminase in viral and bacterial pneumonia.we measured the activity of serum adenosine deaminase (ada) in paired sera from 171 military conscripts with radiographically verified pneumonia. patient serum samples were selected on the basis of serologic analyses identifying as single etiologic agents streptococcus pneumoniae in 29 patients, haemophilus influenzae in 7, mycoplasma pneumoniae in 43, adenovirus in 24, influenza a or b in 12, and parainfluenza in 5 patients. in 14 patients neisseria meningitidis and in 31 chlamydia spp were con ...19911899819
update: influenza activity--united states and worldwide, and the composition of the 1991-92 influenza vaccine. 19911901134
molecular evolution of hemagglutinin genes of h1n1 swine and human influenza a viruses.the hemagglutinin (ha) genes of influenza type a (h1n1) viruses isolated from swine were cloned into plasmid vectors and their nucleotide sequences were determined. a phylogenetic tree for the ha genes of swine and human influenza viruses was constructed by the neighbor-joining method. it showed that the divergence between swine and human ha genes might have occurred around 1905. the estimated rates of synonymous (silent) substitutions for swine and human influenza viruses were almost the same. ...19911901364
soluble hla-a2.1 restricted peptides that are recognized by influenza virus specific cytotoxic t lymphocytes.the influenza a virus matrix protein derived peptide with amino acids 57-68 (lys-gly-ileu-leu-gly-phe-val-phe-thr-leu-thr-val) is recognized by influenza virus hla-a2 restricted ctl. because of the large number of hydrophobic residues this peptide is very insoluble. substitution with a number of polar amino acids resulted in a soluble peptide (lys-lys-ala-leu-gly-phe-val-phe-thr-leu-asp-lys) that was very effective in sensitizing hla-a2 positive target cells. further substitution of threonine in ...19911904085
community acquired pneumonia: aetiology and prognostic index evaluation.a 10 month prospective study of all adults admitted to waikato hospital with community acquired pneumonia was performed to assess aetiology, mortality, hospital stay, and the value of a prognostic index based on that obtained from a british thoracic society study. the 92 patients in the survey had a mean age of 56 (range 13-97) years. a microbiological diagnosis was established in 72%; streptococcus pneumoniae (33%), mycoplasma pneumoniae (18%), and influenza a virus (8%) were the most common mi ...19911907034
defective presentation of endogenous antigens by a murine sarcoma. implications for the failure of an anti-tumor immune response.mhc class i-restricted ctl play a central role in the immune response against methylcholanthrene (mca)-induced sarcomas in mice. we, therefore, hypothesized that mca-induced tumors may evade immune recognition by failing to present ag to cd8+ ctl. of a number of previously described mca-induced sarcomas, one, mca 101, fails to induce ctl, is nonimmunogenic, and grows rapidly and lethally in nonimmunosuppressed recipients. to better understand the nonimmunogenicity of mca 101 we examined its abil ...19911907999
antibodies that are specific for a single amino acid interchange in a protein epitope use structurally distinct variable regions.we have analyzed how the immune system generates antibodies that are specific for analogues of an epitope on the influenza virus hemagglutinin (ha) that differ solely by the presence of asp or gly at amino acid 225. most antibodies induced in response to ha(asp225) use one of a few closely related variable (v) region structures that are encoded by characteristic vh/vk gene segment combinations. remarkably, none of these vh/vk combinations was induced in response to ha(gly225). instead of modifyi ...19911908510
aetiology of community acquired pneumonia in valencia, spain: a multicentre prospective study.a year long multicentre prospective study was carried out in the valencia region of spain, to determine the cause of community acquired pneumonia. the study was based on 510 of 833 patients with pneumonia. of these, 462 were admitted to hospital, where 31 patients died. a cause was established in only 281 cases--208 of bacterial, 60 of viral, and 13 of mixed infection. the most common microorganisms were streptococcus pneumoniae (14.5%), legionella sp (14%), influenza virus (8%), and mycoplasma ...19911908605
many variable region genes are utilized in the antibody response of balb/c mice to the influenza virus a/pr/8/34 hemagglutinin.we have examined how many different h chain variable (vh) and kappa-chain variable (vk) germ-line genes are used in the antibody response to the influenza virus a/pr/8/34 hemagglutinin (pr8 ha), and have assessed how the expression of individual vh and/or vk genes contributes to the generation of specificity for the ha. a panel of 51 hybridoma antibodies that recognize two antigenic regions on the ha were compared for the sequence of their ig h and l chain v regions. the hybridomas were obtained ...19911908881
erythromycin and phenoxymethylpenicillin (penicillin v) in the treatment of respiratory tract infections as related to microbiological findings and serum c-reactive protein.respiratory tract pathogens (beta-haemolytic streptococci groups a, c and g, haemophilus influenzae, branhamella catarrhalis or pneumococci), were isolated from nasopharyngeal and/or throat swabs in 73/138 (53%) patients greater than 10 years of age with a clinical diagnosis of acute sinusitis, acute tonsillitis, purulent nasopharyngitis or acute bronchitis. serological evidence of a viral infection (influenza a and b, parainfluenza 1, 2 and 3, respiratory syncytial virus, adenovirus) or mycopla ...19911909052
influence of a v kappa 8 l chain transgene on endogenous rearrangements and the immune response to the ha(sb) determinant on influenza virus.a rearranged murine v kappa 8/j kappa 5 l chain gene that codes for the l chain of most antibodies generated in the primary response of balb/c mice to the antigenic site, sb, of the hemagglutinin (ha) molecule of influenza virus a/pr/8/34 (pr8) has been cloned. three transgenic lines were generated by microinjecting the gene. lines ga and l each contain a single copy of the transgene whereas line gb contains three complete copies. mice of the ga lineage showed increased v kappa 8-specific mrna l ...19911909739
nuclear transport of influenza virus ribonucleoproteins: the viral matrix protein (m1) promotes export and inhibits import.because influenza virus replicates in the nucleus and buds from the plasma membrane, its ribonucleoproteins (rnps) must undergo bidirectional transport across the nuclear membrane. export from the nucleus to the cytoplasm was found to depend on the viral matrix protein (m1). m1 associated with newly assembled viral rnps (vrnps) in the nucleus and escorted them to the cytoplasm through the nuclear pores. in contrast, during entry of the virus into a new host cell, m1 protein dissociated from the ...19911913813
atp is required for in vitro assembly of mhc class i antigens but not for transfer of peptides across the er membrane.we have translated the hla-b27 heavy chain in vitro and studied its assembly with beta 2-microglobulin and peptide in microsomes from human cells. the assembly process requires atp. however, the translocation of peptide across the endoplasmic reticulum (er) membrane does not require atp, and binding of biotinylated peptide to bip, an er luminal protein, occurs after atp depletion. proteinase k treatment of the microsomes does not block peptide translocation. thus, atp is required in the lumen of ...19911913823
superiority of live attenuated compared with inactivated influenza a virus vaccines in older, chronically ill adults.forty-eight older adults with chronic diseases were vaccinated intranasally with live attenuated influenza a/korea/1/82 (h3n2), cr59 virus. forty-two (88 percent) cr59 virus recipients became infected with vaccine virus without adverse effects or change in mean pulmonary function even among the 29 infected recipients with moderate to severe chronic obstructive pulmonary disease. among control groups who received either monovalent or trivalent inactivated influenza virus vaccines intramuscularly, ...19911914615
clearance of influenza virus respiratory infection in mice lacking class i major histocompatibility complex-restricted cd8+ t cells.transgenic mice homozygous for a beta 2-microglobulin (beta 2-m) gene disruption and normal mice that had been treated with a cd8-specific mab were infected intranasally with an h3n2 influenza a virus. both groups of cd8t cell-deficient mice eliminated the virus from the infected respiratory tract. potent ctl activity was detected in lung lavage populations taken from mice with intact cd8+ t cell function, with minimal levels of cytotoxicity being found for inflammatory cells obtained from the a ...19911919440
monovalent sialosides that bind tightly to influenza a virus. 19911920363
three-dimensional structure of the neuraminidase of influenza virus a/tokyo/3/67 at 2.2 a resolution.an atomic model of the tetrameric surface glycoprotein neuraminidase of influenza virus a/tokyo/3/67 has been built and refined based on x-ray diffraction data at 2.2 a resolution. the crystallographic residual is 0.21 for data between 6 and 2.2 a resolution and the r.m.s. deviations from ideal geometry are 0.02 a for bond lengths and 3.9 degrees for bond angles. the model includes amino acid residues 83 to 469, four oligosaccharide structures n-linked at asparagine residues 86, 146, 200 and 234 ...19911920428
refined atomic structures of n9 subtype influenza virus neuraminidase and escape mutants.the crystal structure of the n9 subtype neuraminidase of influenza virus was refined by simulated annealing and conventional techniques to an r-factor of 0.172 for data in the resolution range 6.0 to 2.2 a. the r.m.s. deviation from ideal values of bond lengths is 0.014 a. the structure is similar to that of n2 subtype neuraminidase both in secondary structure elements and in their connections. the three-dimensional structures of several escape mutants of neuraminidase, selected with antineurami ...19911920429
enhanced and prolonged pulmonary influenza virus infection following phosgene inhalation.animal infectivity models have been important in the demonstration of enhanced susceptibility to viral and bacterial infection as a result of low-level toxicant exposure. this study demonstrated an enhanced and prolonged viral infection using an influenza virus infectivity model in the rat following exposure to the toxicant gas phosgene. fischer-344 rats exposed to either air or a sublethal concentration of phosgene demonstrated peak pulmonary influenza virus titers 1 d after infection. virus ti ...19911920529
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