Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| pilot evaluation of influenza virus vaccine (ivv) combined with adjuvant. | the safety of licensed influenza virus vaccine (ivv) combined with a novel adjuvant containing muramyl tripeptide (mtp) conjugated to phosphatidylethanolamine (pe) was evaluated in a randomized pilot study. ten healthy 23-30-year-old men were given a single intramuscular dose of ivv combined with saline (n = 5) or with 100 micrograms of mtp-pe in the mf59 adjuvant emulsion (mf59-100) (n = 5). evaluations were performed on days 0, 1, 2, 4, 7 and 28 after inoculation. ivv alone was well tolerated. ... | 1993 | 8212835 |
| determination of hemagglutination-inhibition titers to influenza a virus in porcine sera by use of an enzyme-linked immunosorbent assay. | an elisa-based method to estimate hemagglutination-inhibition (hi) titer was developed. subtype specificity was obtained by using purified h1 and h3 hemagglutinin antigens. using the linear relation that exists between elisa and hi methods, regression lines for h1n1- and h3n2-monospecific porcine antisera were constructed. approximation of actual hi titer could be obtained from insertion of elisa values into the appropriate regression line. the hi estimations were within 50% of the actual measur ... | 1993 | 8214894 |
| the subclass igg responses of mice to influenza surface proteins formulated into liposomes. | unprimed mice and mice primed by prior infection with an h1n1 subtype of influenza virus were used to assess the total and subclass igg serum antibody responses to influenza virus a/sichuan/2/87 (h3n2) surface haemagglutinin and neuraminidase proteins incorporated into four different formulations of liposomes. only one of these liposome preparations, dspc(b), induced greater total igg, and subclass igg1 and igg2a antibody levels, in sera from both primed and unprimed mice than the aqueous a/sich ... | 1993 | 8215299 |
| comparative anti-influenza virus activity of 2'-deoxy-2'-fluororibosides in vitro. | the anti-influenza virus activity of 2'-deoxy-2'-fluoroguanosine was determined in cell culture and in explants of human respiratory epithelium by yield reduction assay. the concentration causing at least 1.0 log10 reduction in influenza a (h3n2) virus yield (ec90) at 24 h was 2.5 micrograms/ml in primary rhesus monkey kidney and 12 micrograms/ml in madin-darby canine kidney (mdck) cells, compared to 0.5 micrograms/ml and 0.9 micrograms/ml, respectively, for ribavirin. the estimated therapeutic ... | 1993 | 8215305 |
| [evaluation of seroconversion after vaccination against influenza during the epidemic season 1991-1992 in poland]. | vaccination was performed by influenza virus vaccine trivalent type a and b. we vaccinated about 75,000 persons in poland in different groups of age. hi and ni tests were used for testing antibody level for a/taiwan/1/86 (h1n1), a/beijing/353/89 (h3n2) and b/panama/45/90. the rise of antibody level was statistically significant. | 1993 | 8234846 |
| comparison of 10 influenza a (h1n1 and h3n2) haemagglutinin sequences obtained directly from clinical specimens to those of mdck cell- and egg-grown viruses. | pcr was used to amplify and sequence the complete ha1 region of the haemagglutinin (ha)-encoding genes of 10 clinical isolates of influenza virus of the h1n1 or h3n2 subtypes. these sequences were compared to those obtained from viruses isolated from the same specimens after passage in eggs and mdck cells. amino acid substitutions in the egg-derived ha sequences were found in nine out of the 10 specimens analysed, whereas seven out of eight of the mdck-derived ha sequences were identical to thos ... | 1993 | 8245870 |
| [pneumonia diagnosis in living swine using lung lavage]. | in pigs coming from fattening units with tenacious pneumonitis problems the attempt was made to find an etiological diagnosis in living pigs by bronchoalveolar lavage (bal) and serological examinations on antibodies against mycoplasma hyopneumonia, actinobacillus pleuropneumoniae and influenza-a-virus (serotypes h1n1 and h3n2). in some cases the results of the bacteriological examinations of the bal were compared with the post mortem findings. both methods yield similar results. mycoplasma hyopn ... | 1993 | 8250824 |
| recombinant secreted haemagglutinin protects mice against a lethal challenge of influenza virus. | balb/c mice were immunized with 2 x 2 micrograms of purified recombinant secreted haemagglutinin, derived from the a/victoria/3/75 (h3n2) virus. in the first immunization, ribi adjuvant was used, while for the booster injection a monophosphoryl lipid a/muramyl dipeptide combination was chosen. mice immunized in this way were 90-100% protected against a challenge with 20 ld50 of mouse-adapted, homologous virus (strain x47). bromelain-solubilized haemagglutinin gave only 70% protection under compa ... | 1993 | 8256499 |
| susceptibilities to rimantadine of influenza a/h1n1 and a/h3n2 viruses isolated during the epidemics of 1988 to 1989 and 1989 to 1990. | clinical isolates of influenza a viruses identified during outbreaks in two winters were tested for their rimantadine susceptibilities by an enzyme-linked immunosorbent assay modified from that described previously by belshe et al. (r. b. belshe, b. burk, f. newman, r. l. cerruti, and i. s. sim, j. virol. 62:1508-1512, 1988). the infectivity titer and the 50% inhibitory concentration of rimantadine were calculated for each virus. of 105 influenza virus a isolates tested, 28 influenza a/h1n1 isol ... | 1993 | 8257151 |
| [a method of competitive dot hydridization for genotyping influenza a viruses]. | a new method for genetic typing of influenza viruses using molecular hybridization of dna-rna was developed which consisted in addition to the hybridization solution, apart from the radioactively labeled probe, of rna of a virus with known gene homologous to the plasmid dna used as the probe but belonging to a different serosubtype of influenza a virus, other than cloned kdna, (within the range of h1n1, h2n2, and h3n2). this competitive rna (rnac) is added in considerable excess with regard to b ... | 1993 | 8284914 |
| combined effect of selected antiviral substances of natural and synthetic origin. ii. anti-influenza activity of a combination of a polyphenolic complex isolated from geranium sanguineum l. and rimantadine in vivo. | the synergistic effect shown by the combination of a natural product, polyphenolic complex (pc) isolated from geranium sanguineum l., and rimantadine (r) in vitro and in ovo [7], encouraged us to continue these studies by in vivo testing. a marked protective effect in experimental influenza virus a (h3n2) infection in mice was found when pc was applied nasally (i.n.) (1.0 mg/kg) only once 6 h before infection in combination with r applied orally in concentration 10.5 and 2.5 mg/kg 2h before and ... | 1993 | 8285131 |
| [seroepidemiological data on the circulation of influenza virus in moldova in 1991-1992]. | 1. to establish the predominant circulating antigenic subtypes of influenza viruses in the epidemic season (19911992). 2. to evaluate the efficiency of seroepidemiological method in determining the circulating antigenic subtypes and its practical consequences. | 1993 | 8153476 |
| induction of cd8+ cytotoxic t cells by immunization with killed influenza virus and effect of cholera toxin b subunit. | the mhc class i cytotoxic t-lymphocyte (ctl) response in mice given formalin-inactivated influenza whole-virus vaccine (wvv) with or without cholera toxin b subunit (ctb) was studied. intraperitoneal injection of balb/c (h-2d) mice with high doses of a/taiwan/1/86 (h1n1) wvv stimulated influenza a virus-specific ctl response in a dose-dependent manner. a dose of 4.4 or 44 micrograms induced ctl response equal to or greater than live influenza virus infection. coadministration of vaccine with 5 o ... | 1993 | 7903015 |
| combined antiinfluenza activity of a plant preparation shs-174 and amantadine derivatives. | the results of the study on the combined antiviral activity of the shs-174 preparation (a lyophylized infusion from three higher plants) and three amantadine derivatives (rimantadine, amantadine glucuronide and its derivative) are presented. the antiviral effect of the drugs on the reproduction of influenza virus strains a/h1n1 and a/h3n2 in vitro was studied. the combined antiviral effect was evaluated on the basis of viral yields and in many cases a synergism was found. the most synergistic ef ... | 1993 | 7905240 |
| [influenza and other acute respiratory infections. republic of cuba, 1989]. | information is provided on the epidemiological situation of influenza and other acute respiratory tract diseases in cuba during 1989. general mortality rate was 25.4 per 105 inhabitants. global morbidity rate was 373.9 per 1,000 inhabitants. the highest morbidity rate reported corresponded to children 5-14 years old and under 1 year of age. serologically, the viral agent proportionally most identified was influenza virus type a (h3n2). | 1993 | 7800896 |
| alpha 2-macroglobulin is the major neutralizing inhibitor of influenza a virus in pig serum. | horse, pig, and rabbit sera contain distinct glycoprotein inhibitors of influenza a viruses that inhibit hemagglutinating activity and neutralize viral infectivity. although alpha 2-macroglobulin has been identified as the inhibitor in horse serum, the inhibitors in pig and rabbit sera have not been identified. as an initial step in elucidating the structural differences among inhibitor molecules, we sought to isolate the inhibitor in pig serum. the purified inhibitor decreased the hemagglutinat ... | 1993 | 7681613 |
| prominent usage of v beta 8.3 t cells in the h-2db-restricted response to an influenza a virus nucleoprotein epitope. | the spectrum of tcr usage has been analyzed for virus-specific cd8+ t cells isolated from the regional mediastinal lymph modes and from the lung by bronchoalveolar lavage (bal) of c57bl/6 (b6) mice with influenza pneumonia. lymphocytes were recovered during the acute phase of the primary response in mice infected with an h3n2 (a/hkx31) virus, or in immune animals that were secondarily challenged with an h1n1 virus (a/pr8). cells taken directly from the bal of infected mice exhibited an increase ... | 1993 | 7689611 |
| a new influenza virus a/h3n2 variant of taiwan origin. | a clinical isolate of influenza virus a/h3n2 from a one-year-old boy with pharyngitis was examined by using rna-polymerase chain reaction (pcr) for amplification of viral cdna and subsequent dna sequencing with asymmetric pcr. since antigenic drift has been found in recent a/h3n2 isolates, this strain was compared with a/shanghai/24/90 and other a/h3n2 strains, collected at the centers for disease control and prevention (cdc) in atlanta, ga, usa. it was found that the steady changes of amino aci ... | 1993 | 7988282 |
| [the isolation of a reassortant strain of the a/kiev/59/79, r (h1n1) influenza virus and its genomic characteristics]. | as a result of two successive recombinations of influenza a viruses: a/leningrad/0139/76 (h3n2) with a/pr/8/34 (h1n1) strain and the resulting reassortant a/leningrad/0139/76, r (h3n2) with a field isolate a/kiev/59/79 (h1n1), a virus. a/kiev/59/79, r (h1n1) was obtained. it was established by electrophoresis in polyacrylamide gel and sequencing of kdna fragments of its genome that the genes pb2, pb1 and np of this virus belonged to serosubtype h3n2, while genes pa, m, and ns to serosubtype h1n1 ... | 1993 | 8059522 |
| serological studies on the potential synergism of porcine reproductive and respiratory syndrome virus and influenza-, corona- and paramyxoviruses in the induction of respiratory symptoms in swine. | sera from 265 finishing pigs belonging to 70 herds, in which severe respiratory disorders were observed, were examined for antibody prevalence to porcine reproductive and respiratory syndrome virus (prrsv), influenza virus subtypes h3n2 and h1n1, porcine respiratory corona virus (prcv) and a recently described porcine paramyxovirus (ppmv). by immunoperoxidase-monolayer assay 69.1% of these sera were positive for prrsv. hemagglutination inhibiting activity was found in 55.1% of the sera for influ ... | 1993 | 8128802 |
| induction of interferon in human leukocyte cultures by natural pathogenic respiratory viruses. | some common viruses responsible for respiratory disease have been reported to be poor inducers of interferon (ifn). therefore, we have studied the induction of ifn in cultures of human leukocytes exposed under standardized conditions to various concentrations of adenovirus type 7a, coronavirus 229e, an influenza type a virus (h3n2), a rhinovirus, and respiratory syncytial virus (rsv). all five viruses induced substantial amounts of ifn at a multiplicity of infection of one infectious unit per ce ... | 1993 | 8151137 |
| immunogenicity and adverse reactions of influenza vaccination in elderly patients given acetaminophen or placebo. | the objective was to examine the antibody responses to influenza immunization in an elderly population and the effect of prophylactic acetaminophen on adverse responses due to inactivated whole virus vaccine containing influenza a (h3n2 and h1n1) and b antigens. during the autumn of 1990, 100 patients 65 years or older were immunized and randomly allocated to receive placebo or 1,950 mg (2 x 975 mg) of acetaminophen. they recorded any local and systemic side effects over a 3-day period. serology ... | 1993 | 15566726 |
| [serologic study for determining the circulation of respiratory viruses in havana city]. | during 1991, 2,400 serum samples from subjects under 15 years, and 2,400 serum samples from subjects with the same age or over 15 years were assessed against antigens of 7 respiratory viruses by the complement fixation test or by the haemagglutination inhibition technique. the results from these investigations allowed to determine the little circulation of the respiratory syncytial virus which may result in an increase of a susceptible population and the occurrence of outbreaks. the endemic stat ... | 1992 | 9768216 |
| [the therapeutic effect of aprotinin inhalations in influenza and paramyxovirus infections in mice]. | mice infected with influenza a/aichi/2/68 (h3n2) virus or sendai/960 paramyxovirus were treated by inhalations of aerosol aprotinin, a broad spectrum inhibitor of proteinases. a course of inhalations of finely dispersed aerosol aprotinin including 4 exposures of 35-40 min each daily for 6 days provided respiratory administration of aprotinin in a dose about 100 kallikrein-inhibiting u/mouse per day. in mice treated by aprotinin inhalations, histological examinations showed decreased pulmonary pa ... | 1992 | 1281946 |
| [the determination of the genotype of natural reassortant influenza a viruses according to the core protein genes by the methods of competitive dot hybridization and sequencing]. | simultaneous circulation of different subtypes of influenza a viruses provides conditions for reassortant strains formation. a comparative investigation of genome of 47 influenza a virus strains (h1n1, h2n2, and h3n2) was carried out by competitive dot hybridization technique and sequence analysis of some of cdna-copies of the virus genes. all the genes of 43 strains encoding nonglycolysed proteins corresponded to the serum subtype of surface glycoproteins. the reassortant pattern of genome for ... | 1992 | 1290222 |
| [seroconversion after vaccine with trivalent influenza vaccine during the epidemic season 1990/1 in poland]. | vaccination was performed by influenza virus vaccine, trivalent type a and b. we vaccinated about 50,000 persons in poland in different groups of age. hi and ni tests were used for testing antibody level for a/taiwan/1/86 (h1n1), a/shanghai/16/89 (h3n2) and b/yamagata/16/89. the rise of antibody level was statistically significant. | 1992 | 1296247 |
| [the laboratory epidemiological study of the joint circulation of the influenza virus a subtypes a/h1n1/ and a/h3n2/ in bulgaria]. | the national influenza center of bulgaria made the epidemiological analysis of the spread of influenza virus, type a, for the period of 11 years on the basis of mass laboratory investigations. subtype a (h1n1) was found to be the main factor of epidemics in 1978 and 1982, while the epidemics of 1980, 1983, 1985, 1986, 1987 and 1988 were mainly caused by subtype a (h3n2). the data of laboratory and epidemiological studies indicated that after 20-year absence influenza virus a, subtype a (h1n1), w ... | 1992 | 1301658 |
| [influenza surveillance]. | from 1982 to june 1990, seven influenza a (h3n2) epidemics and four influenza a (h1n1) epidemics occurred in shanghai, and several new variants of influenza virus were isolated. during that period, influenza a (h3n2) and influenza a (h1n1) appeared alternatively while each lasted for one to two years. the epidemic peak of influenza usually was seen from july to august and late winter to early spring. the subtype which appears in july and august usually starting in late winter and early spring in ... | 1992 | 1303322 |
| [epidemiological and virological research on influenza and viral respiratory infections in the southeastern region of romania in the cold season of 1991-1992]. | investigations pointed out the high level of respiratory diseases and pneumonias in children, especially in the youngest ones (0-1 year-old) during all the surveyed period. an influenza outbreak during the second half of february was registered in the infantile population--school and low-age children--which gave most of the cases. serology and isolations incriminated an influenza virus related to the a/beijing 353/89 (h3n2) strain. isolations worked out after the influenza epidemics pointed out ... | 1992 | 1308431 |
| alterations to influenza virus hemagglutinin cytoplasmic tail modulate virus infectivity. | the influenza virus hemagglutinin (ha) contains a cytoplasmic domain that consists of 10 to 11 amino acids, of which five residues have sequence identity for 10 of 13 ha subtypes. to investigate properties of these conserved residues, oligonucleotide-directed mutagenesis was performed, using an ha cdna of influenza virus a/udorn/72 (h3n2) to substitute the conserved cysteine residues with other residues, to delete the three c-terminal conserved residues, or to remove the entire cytoplasmic domai ... | 1992 | 1309913 |
| variation in seropositivity for some respiratory disease agents in finishing pigs: epidemiological studies on some health parameters and farm and management conditions in the herds. | the relationship between the extent of seropositivity for aujeszky's disease virus (adv), actinobacillus pleuropneumoniae (app.) serotype 2 and porcine influenza (pi) viruses serotype h1n1 and h3n2 in pigs on the one hand and the health status of the pigs and some farm and management conditions in the herds on the other hand was studied in 45 pig finishing herds, all members of one integration group. the health status was assessed by the extent of clinical signs, the use of veterinary drugs and ... | 1992 | 1315466 |
| antibody responses of swine to type a influenza viruses in the most recent several years. | a serological survey was conducted on 4,080 swine sera collected for the years 1985-90. the swine sera positive to a/new jersey/8/76 (swine type h1n1) strain were observed in annual (10-20%) and monthly (20-40%) incidences during the observation period except for occasional months. antibodies to recent human h1n1 viruses in swine were recognized in relation to the human h1n1 influenza epidemics. antibody responses of swine to human h3n2 strains appeared irrespective of human epidemics with the v ... | 1992 | 1318751 |
| influenza a viruses: epidemiologic study in fatteners in spain (1987-89). | 2,979 sera were collected from slaughtered swine in two geographic areas of spain from 1987 to 1989. they were tested for antibodies against an h1n1- and h3n2-influenza virus by haemagglutination-inhibition tests (hi). the percentage of positive sera was higher in area i (78%-69.2%) than in area ii (63.1%-60.4%) for both viruses respectively. the coexistence of high titres to both h1n1- and h3n2-influenza virus became apparent in cold months simultaneously in each area, although influenza viruse ... | 1992 | 1320310 |
| antigenic variant of swine influenza virus causing proliferative and necrotizing pneumonia in pigs. | a new antigenic variant of swine influenza virus was isolated from the lungs of pigs experiencing respiratory problems in 7 different swine herds in quebec. pigs of different ages were affected, and the main clinical signs were fever, dyspnea, and abdominal respiration. coughing was not a constant finding of the syndrome. at necropsy, macroscopic lesions included the overall appearance of pale animals, general lymphadenopathy, hepatic congestion, and consolidation of the lungs. histopathologic f ... | 1992 | 1333815 |
| pathogenicity of concurrent infection of pigs with porcine respiratory coronavirus and swine influenza virus. | combinations of porcine respiratory coronavirus (prcv) and either of two swine influenza viruses (h1n1 or h3n2) were administered intranasally and by aerosol to six- to eight-week-old specific pathogen-free pigs. the clinical responses, gross respiratory lesions and growth performances of these pigs were studied and compared with those of single (prcv, h1n1 or h3n2) and mock-infected animals. prcv infection caused fever, growth retardation and lung lesions, but no respiratory symptoms. infection ... | 1992 | 1334565 |
| do antigenic drift residues in influenza hemagglutinins of the h3 subtype qualify as contact sites for mhc class ii interaction? | we have previously reported that a majority of hemagglutinin-specific and class ii (ak or ad)-restricted t cell clones, elicited by natural infection with x31 virus (h3n2 subtype), focus on regions of the ha1 subunit that have featured in antigenic drift and exhibit extensive diversity in their ability to discriminate between variant viruses with amino acid substitutions in these sites. the structural basis for the loss of recognition of a major antigenic site, ha1 120-139, was investigated by ( ... | 1992 | 1358189 |
| antigenic and molecular analysis of influenza a(h3n2) virus strains isolated in 1985 in open and closed communities of northern germany. | antigenic and molecular analyses of influenza a(h3n2) virus strains isolated in 1985 during outbreaks in open and closed communities of north germany were carried out. the data obtained have shown that 11 strains isolated in a closed orphanage were antigenically similar to each other. the electrophoretic mobilities of either ha, np, m1 and ns1 polypeptides or of double stranded rna segments were indistinguishable. analysis of viruses isolated at the same time from open communities has revealed t ... | 1992 | 1359765 |
| virus-specific immune response in the lungs of mice infected with influenza virus. | the time course of primary humoral immune response in nfs/n mice infected with the adapted influenza virus a/aichi 2/68(h3n2) was followed by determination of the different class immunoglobulins in lungs, lung washings, and in blood serum. the quantity of antibody-producing cells (apc) was estimated by local haemolysis in gel. the presence of antibodies in serum and lavage fluid was tested by the methods of radial haemolysis and radial immunodiffusion. it was shown that the local immune response ... | 1992 | 1359766 |
| influenza a virus transfectants with chimeric hemagglutinins containing epitopes from different subtypes. | influenza virus transfectants with chimeric hemagglutinins were constructed by using a ribonucleoprotein transfection method. transfectants w(h1)-h2 and w(h1)-h3 contained a/wsn/33(h1n1) (wsn) hemagglutinins in which the six-amino-acid loop (contained in antigenic site b) was replaced by the corresponding structures of influenza viruses a/japan/57(h2n2) and a/hong kong/8/68(h3n2) (hk), respectively. serological analysis indicated that the w(h1)-h3 transfectant virus reacted with antibodies again ... | 1992 | 1370088 |
| influenza viruses differ in recognition of 4-o-acetyl substitution of sialic acid receptor determinant. | equine alpha 2-macroglobulin (em), known to contain both neu5ac and neu4,5ac2 sialic acid residues, was treated with vibrio cholerae sialidase for the selective removal of neu5ac and was compared with the untreated em for its binding by a panel of influenza viruses. type a h3n2 virus strains having leu in position 226 of their hemagglutinin (ha) changed the affinity for sialidase-treated em only slightly, if at all, indicative of their ability to bind the 4-o-ac-substituted neu5ac receptor deter ... | 1992 | 1374985 |
| influenza virus infection elicits class ii major histocompatibility complex-restricted t cells specific for an epitope identified in the ns1 non-structural protein. | a t cell epitope of the influenza virus ns1 molecule was identified and shown to be a determinant used in class ii major histocompatibility complex-restricted t cell responses to infectious virus. an i-ed-restricted balb/c mouse t hybridoma clone recognizing influenza virus a/puerto rico/8/34 (pr8; subtype h1n1) but not a/udorn/72 (subtype h3n2) secreted lymphokines in response to purified recombinant ns1 or fusion proteins containing amino acids 1 to 81 or 1 to 42 of ns1. as expected for recogn ... | 1992 | 1376767 |
| update: influenza activity--united states and worldwide, 1992. | during the 1991-92 influenza season, influenza activity was reported at moderate levels in many parts of the world. influenza a(h1n1), a(h3n2), and influenza b viruses have continued to circulate worldwide. from october 1991 through february 1992, when influenza viruses circulated widely in the northern hemisphere, epidemic levels of activity were most commonly associated with the h3n2 subtype of influenza a (1). this report summarizes worldwide influenza activity reported from march through sep ... | 1992 | 1383682 |
| [a case of invasive broncho-pulmonary aspergillosis associated with influenza a (h3n2) infection]. | a 49-year-old man with high alcohol consumption was admitted with fever, cough and progressive dyspnea after a one week history of influenza-like symptoms. chest x-ray film on admission showed diffuse peribronchial shadows and patchy infiltration in the right lower lung field. chest x-ray film the following day and chest ct film on the 4th day of admission showed multiple nodular shadows and cavity formation. at bronchoscopy the bronchial surface was covered by white plaque, and asp. fumigatus w ... | 1992 | 1405113 |
| [preparative isolation of basic structural proteins of the influenza virus]. | the schemes for preparative electrophoretic isolation and purification of major proteins from influenza virus are described. the viral envelope protein, hemagglutinin, two of its subunits, internal m and np proteins of influenza viruses a/fpv/rostock (h7n1), a/pr/8/34 (h1n1) and x-31 (h3n2) were obtained in preparative amounts and characterized by amino acid and n-terminus analyses. | 1992 | 1406760 |
| a strategy for making synthetic peptide vaccines. | we have determined the h-2 class ii allele-specific amino acid motif of the agretope (the site of contact between the peptide antigen and the major histocompatibility complex) for a synthetic peptide composed of residues 43-58 of pigeon cytochrome c (p43-58). residues 46 and 54 functioned as the agretope, and residues 50 and 52 functioned as the epitope (the site for contact between the peptide antigen and the t-cell antigen receptor). in general, agretopes and epitopes function independently. t ... | 1992 | 1409595 |
| nucleotide sequence changes in the polymerase basic protein 2 gene of temperature-sensitive mutants of influenza a virus. | influenza a viruses bearing temperature-sensitive (ts) mutations are restricted in replication in the respiratory tract of animals and humans and are therefore attenuated. nucleotide sequences were determined for the rna segment coding for the polymerase basic protein 2 (pb2) from a panel of 12 influenza a/udorn/307/72 (h3n2) ts viruses, previously characterized to have a ts mutation in the pb2 gene. each of the viruses with a ts mutation in the pb2 gene had a single amino acid change located at ... | 1992 | 1413525 |
| [the antigenic characteristics of the influenza virus subpopulations isolated from a single patient]. | examinations by hi and eia of influenza a (h3n2) virus isolates of 1985-1990 showed the strains derived from nasopharyngeal washings from patients to present very frequently as phenotypic mixtures of stable virus variants. immunological analysis with monospecific antibody to hemagglutinin antigenic sites revealed a wide spectrum of antigenic activity based on the degree of relationship with viruses of previous years. by means of the immune pressing with antibody of different specificity the isol ... | 1992 | 1413713 |
| increased influenza a virus sialidase activity with n-acetyl-9-o-acetylneuraminic acid-containing substrates resulting from influenza c virus o-acetylesterase action. | influenza virus type c (johannesburg/1/66) was used as a source for the enzyme o-acetylesterase (ec 3.1.1.53) with several natural sialoglycoconjugates as substrates. the resulting products were immediately employed as substrates using influenza virus type a [(singapore/6/86) (h1n1) or shanghai/11/87 (h3n2)] as a source for sialidase (neuraminidase, ec 3.2.1.18). a significant increase in the percentage of sialic acid released was found when the o-acetyl group was cleaved by o-acetylesterase act ... | 1992 | 1413991 |
| the attenuation phenotype conferred by the m gene of the influenza a/ann arbor/6/60 cold-adapted virus (h2n2) on the a/korea/82 (h3n2) reassortant virus results from a gene constellation effect. | a single gene reassortant (sgr) virus that derived its m gene from the attenuated influenza a/ann arbor/6/60 cold-adapted (ca) donor virus and the remaining genes from the a/korea/82 (h3n2) wild type (wt) virus (designated a/korea/82 ca m-sgr) was previously shown to be attenuated in mice, hamsters, ferrets, and humans. the attenuation (att) phenotype of this sgr virus could result directly from an altered function of the mutant m gene product of the a/ann arbor/6/60 ca virus, which differs from ... | 1992 | 1413993 |
| influenza vaccine effectiveness in preventing hospitalization for pneumonia in the elderly. | during the winter of 1989-1990, influenza type a(h3n2) circulated widely, causing excess morbidity and mortality nationwide. from november through april, 1989-1990, hospitalized cases of pneumonia and influenza occurring among noninstitutionalized individuals 65 or more years of age were identified by 20 acute care hospitals in southern lower michigan. these cases were group matched on age, sex, race, and zip code to randomly sampled, community-based controls from a comprehensive listing of medi ... | 1992 | 1415151 |
| [microsomal hydroxylating system of the mouse liver in toxic forms of influenza infection]. | the paper presents the experimental model of toxic influenza infection induced by a/victory/35/72 (h3n2) strain adapted to cba mice. the virus toxicosis was shown by means of esr technique to be accompanied by a decrease of both the content of the active form of cytochrome p-450 and the activity of p-nitroanisole o-demethylase. in microsomes there was activation of lipid peroxidation (lp) and an increase of microviscosity of lipid matrix. lp activation in microsomes was not accompanied by the ch ... | 1992 | 1421306 |
| type-specific identification of influenza viruses a, b and c by the polymerase chain reaction. | the aim of this study was to develop a polymerase chain reaction for specific detection of influenza a, b, and c rna genomes. three primer sets were selected from conserved regions of the genome coding for the non-structural proteins and were tested on 61 influenza a (22 h1n1, 9 h2n2, and 30 h3n2), 11 influenza b, and three influenza c isolates. specific amplified products were obtained with all these strains after electrophoresis on a 2% agarose gel. the specificity of the reaction was increase ... | 1992 | 1430057 |
| liposomes enhance the immunogenicity of reconstituted influenza virus a/pr/8 envelopes and the formation of protective antibody by influenza virus a/sichuan/87 (h3n2) surface antigen. | reconstituted influenza virus (a/pr/8 strain) envelopes (rive) and influenza virus (a/sichuan/87 (h3n2) strain) surface antigens were entrapped in dehydration-rehydration vesicles (drv liposomes) composed of egg phosphatidylcholine (pc) or distearoyl phosphatidylcholine (dspc drv) and equimolar (32 mumol) cholesterol. entrapment values for rive were 31.2 (pc) and 29.4% (dspc drv) of the material used. corresponding entrapment values for the a/sichuan/87 strain antigens were 40.7 and 39.3%. balb/ ... | 1992 | 1441730 |
| [the correction of the functional activity of alveolar macrophages in inducing a primary immune response in influenza]. | the functional activity of alveolar macrophages obtained from mice, both healthy and infected with influenza virus a/aichi 2/68 (h3n2), as manifested by their capacity to initiate the development of primary immune response to sheep red blood cells and escherichia coli lipopolysaccharide after the transfer of these macrophages to intact syngeneic recipients was studied. the capacity of alveolar macrophages to perform antigen-presenting functions in the induction of humoral immune response was sho ... | 1992 | 1496877 |
| influenza vaccine strain selection: equivalence of two antigenically distinct haemagglutinin variants of 1989 h3n2 influenza a virus in protection of mice. | precise antigenic analysis with haemagglutinin-inhibition (hi) tests of 1989 h3n2 influenza a viruses with polyclonal ferret, rabbit and mouse antisera has shown, first, significant differences among 1989 wild-type isolates, second, antigenic differences between two high-yield vaccine candidate reassortant viruses, third, significant antigenic differences of one reassortant (x-105) from the wild-type virus (a/guangdong a/39) from which it was derived, and fourth, dependence of antigenic characte ... | 1992 | 1502837 |
| influenza virus a infection induces interleukin-8 gene expression in human airway epithelial cells. | to determine the role of the airway epithelial cell in mediating virus-induced inflammation, we infected primary cultures of human airway epithelial cells with human influenza type a/port chalmers/72 (h3n2). after two days, the medium was collected for measurement of the chemotactic cytokine interleukin-8 by enzyme-linked immunosorbent assay. the rna was extracted from the cells for analysis of interleukin-8 mrna by northern blot analysis. interleukin-8 production was more than doubled by viral ... | 1992 | 1516705 |
| phase 1 clinical tests of influenza mdp-virosome vaccine (kd-5382). | mdp-virosome vaccine, which contains haemagglutinin (ha) and neuraminidase (na) antigens isolated from influenza virus combined with 6-o-(2-tetradecylhexadecanoyl)-n-acetylmuramoyl-l-alanyl-d-isoglutamine) (b30-mdp) and cholesterol was tested, in comparison with a currently used ha vaccine, for immunogenicity and adverse reactions on 77 adult male volunteers. the volunteers were divided into eight groups, and each individual was injected subcutaneously once, or twice at a 4 week interval, in the ... | 1992 | 1523876 |
| protective efficacy of combined live intranasal and inactivated influenza a virus vaccines in the elderly. | to evaluate the efficacy of adding intranasal live attenuated cold-adapted influenza a vaccine to inactivated influenza vaccine to prevent influenza a in elderly residents of long-term-care institutions. | 1992 | 1530193 |
| analyzing the distribution of cells expressing mrna for t cell receptor gamma and delta chains in a virus-induced inflammatory process. | acute inflammatory processes are extremely complex, containing sets of activated cells that may be difficult to categorize. the interface between two methodologies for characterizing the involvement of gamma delta t cells, in situ hybridization to detect t cell receptor (tcr) mrna and flow cytometric analysis of surface tcr expression, is utilized here to study the pneumonia caused by intranasal (i.n.) infection of mice with influenza a viruses. substantial numbers of cells expressing mrna for t ... | 1992 | 1535834 |
| superior cross-protective effect of nasal vaccination to subcutaneous inoculation with influenza hemagglutinin vaccine. | intranasal (i.n.) vs. subcutaneous (s.c.) administration of influenza hemagglutinin (ha) vaccine was systematically compared in balb/c mice. mice were immunized with different vaccines, together with cholera toxin b subunit as an adjuvant, and 4 weeks later were challenged with either a small (2 microliters) or a large (20 microliters) volume of mouse-adapted a/guizhou-x (h3n2) virus, each of which gave virgin mice either a nasal or a lung predominant infection. both i.n. and s.c. inoculations o ... | 1992 | 1537382 |
| human influenza a (h1n2) viruses isolated from china. | reassortant influenza a viruses bearing h1 haemagglutinin and n2 neuraminidase were isolated from humans in china between december 1988 and march 1989. as primary isolation of influenza a (h1n2) viruses from humans had not been reported previously, it was of interest to determine the genetic origin of these virus isolates. the haemagglutinins of the h1n2 viruses were antigenically and genetically related to those of h1 viruses isolated world-wide since 1986, and the neuraminidases of these virus ... | 1992 | 1538194 |
| use of single-gene reassortant viruses to study the role of avian influenza a virus genes in attenuation of wild-type human influenza a virus for squirrel monkeys and adult human volunteers. | the transfer of six internal rna segments from the avian influenza a/mallard/new york/6750/78 (h2n2) virus reproducibly attenuates human influenza a viruses for squirrel monkeys and adult humans. to identify the avian influenza a virus genes that specify the attenuation and host range restriction of avian-human (ah) influenza a reassortant viruses (referred to as ah reassortants), we isolated six single-gene reassortant viruses (sgrs), each having a single internal rna segment of the influenza a ... | 1992 | 1551982 |
| immunization of infants and young children with live attenuated trivalent cold-recombinant influenza a h1n1, h3n2, and b vaccine. | seventeen triply seronegative infants and young children, and 15 infants and young children seropositive to all three influenza virus strains were vaccinated intranasally with 10(5) tcid50 of each of three (h1n1, h3n2, and b) live attenuated, cold-adapted influenza vaccine strains. seventeen controls were given placebo. vaccination with trivalent influenza vaccine was not associated with adverse reactions in triply seronegative or seropositive children. overall, 12 (71%), 13 (76%), and 13 (76%) ... | 1992 | 1552202 |
| comparison of different approaches to measuring influenza a virus-specific hemagglutination inhibition antibodies in the presence of serum inhibitors. | the a/los angeles/2/87 (h3n2) (a/la/2/87) virus is sensitive to inhibitors of hemagglutination present in certain human sera. it was found that the effect of these inhibitors could be removed by treating sera with high-concentration receptor-destroying enzyme or trypsin-periodate or by using inhibitor-resistant viruses in the hemagglutination inhibition (hai) test. inhibitor-resistant viruses were not effective for detecting rises in antibody titers in the sera of volunteers infected with the a/ ... | 1992 | 1572989 |
| an outbreak of influenza a (h3n2) in a well immunized nursing home population. | to describe the epidemiologic features of an outbreak of influenza a that occurred in a skilled nursing home although over 90 percent of the resident population had previously received influenza vaccine. | 1992 | 1587976 |
| amino acid sequence identity between the ha1 of influenza a (h3n2) viruses grown in mammalian and primary chick kidney cells. | primary isolation of type a influenza (h3n2) virus in mammalian madin darby canine kidney (mdck) cells results in a virus with haemagglutinin (ha) identical to that of the virus replicating in the infected individual, whereas similar isolation of virus in the embryonated egg results in the selection of variants with amino acid substitutions in the globular head region of the ha molecule. to determine whether other mammalian and avian host cells routinely used in laboratory isolation of influenza ... | 1992 | 1588320 |
| anti-influenza virus effect of some propolis constituents and their analogues (esters of substituted cinnamic acids). | the antiviral activity of six synthetic substances, esters of substituted cinnamic acids, identical with or analogous to some of the constituents of the et2o fraction of propolis was studied in vitro. one of them, isopentyl ferulate, inhibited significantly the infectious activity of influenza virus a/hong kong (h3n2) in vitro and the production of hemagglutinins in ovo. by the use of diverse experimental patterns, it was found that the maximal inhibition of viral reproduction was observed when ... | 1992 | 1593279 |
| emergence and transmission of influenza a viruses resistant to amantadine and rimantadine. | amantadine- and rimantadine-resistant viruses have been recovered from approximately 30% of patients treated for acute h3n2 subtype influenza and less often from their close contacts receiving drug prophylaxis. the limited data suggest that resistant viruses can emerge rapidly during drug therapy, as early as 2-3 days into treatment. these viruses retain their resistance phenotype during multiple passages in the laboratory and appear to be genetically stable in this regard. studies in families a ... | 1992 | 1600749 |
| two distinct serum mannose-binding lectins function as beta inhibitors of influenza virus: identification of bovine serum beta inhibitor as conglutinin. | normal bovine and mouse sera contain a component, termed beta inhibitor, that inhibits the infectivity and hemagglutinating activity of influenza a viruses of the h1 and h3 subtypes. we have previously shown these beta inhibitors to be mannose-binding lectins that apparently act by binding to carbohydrate on the viral hemagglutinin, blocking access of the receptor-binding site to receptors on host cells (e. m. anders, c. a. hartley, and d. c. jackson, proc. natl. acad. sci. usa 87:4485-4489, 199 ... | 1992 | 1602549 |
| origin and evolutionary characteristics of antigenic reassortant influenza a (h1n2) viruses isolated from man in china. | during the 1988/1989 influenza season, five antigenic reassortant influenza a (h1n2) viruses not previously isolated from man were isolated in hebei province, people's republic of china. all isolates contained haemagglutinins (has) and neuraminidases (nas) which were antigenically similar to those of the recent russian (h1n1) and hong kong influenza a (h3n2) viruses, respectively. the results of antigenic and nucleotide sequence analyses revealed that the genes encoding the polymerase, nucleopro ... | 1992 | 1607856 |
| pandemic influenza: a zoonosis? | in the last two decades, influenza a viruses have been found to occur throughout the animal kingdom, mainly in birds, notably aquatic ones, in which infection is largely intestinal, waterborne, and asymptomatic. the domestic duck of southern china, raised in countless numbers all year round mainly as an adjunct to rice farming, is the principal host of influenza a viruses. studies based on hong kong h3n2 viruses from southern china suggest that pandemic strains originate from the domestic duck t ... | 1992 | 1609163 |
| host dependence of naturally occurring temperature-sensitive influenza a viruses and location of their genetic lesions. | naturally occurring temperature-sensitive (ts) strains have been found in large number in human influenza a viruses of all subtypes (j. virol. 41 (1982) 353). further studies have demonstrated that the ts phenotype of these viruses is host-dependent in that they are highly ts in chick embryos and chick embryonic cells, but are ts+ in mdck cells. previous studies have located by complementation tests the ts lesion of two h3n2 viruses (hk/8/68 and ningxia/01/72, also known as xia-ts) on the np gen ... | 1992 | 1626417 |
| rapid diagnosis of influenza a. comparison with elisa immunocapture and culture. | the directigen flu-a is an enzyme immunoassay for detecting in 15 min the influenza a nucleoproteinic antigen directly from specimens after passive adsorption on a cellulose membrane. the test was assessed using 160 frozen (-20 degrees c) specimens collected during the 1988-1989 a/h1n1 influenza epidemic and the 1989-1990 a/h3n2 epidemic. compared to the elisa immunocapture test, the sensitivity of the commercial test was 87.8% and the specificity was 97.6%. when compared to isolation of viruses ... | 1992 | 1634600 |
| cross-protection against influenza virus infection afforded by trivalent inactivated vaccines inoculated intranasally with cholera toxin b subunit. | cross-protection against influenza virus infection was examined in mice, immunized intranasally with a nasal site-restricted volume of inactivated vaccines together with cholera toxin b subunit (ctb) as an adjuvant. the mice were challenged with either a small or a large volume of mouse-adapted virus suspension, each of which gave virgin mice either a predominant upper or lower respiratory tract infection. a single dose of a monovalent influenza a h3n2 virus vaccine with ctb provided complete cr ... | 1992 | 1634780 |
| influenza--united states, 1989-90 and 1990-91 seasons. | during the 1989-90 influenza season, 98% of all influenza viruses isolated in the united states and reported to cdc were influenza a. almost all those that were antigenically characterized were similar to influenza a/shanghai/11/87(h3n2), a component of the 1989-90 influenza vaccine. regional and widespread influenza activity began to be reported in late december 1989, peaked in mid-january 1990, and declined rapidly through early april 1990. most of the outbreaks reported to cdc were among nurs ... | 1992 | 1635548 |
| the iga and subclass igg responses and protection in mice immunised with influenza antigens administered as iscoms, with fca, alh or as infectious virus. | comparative studies on the local iga, and circulating igg subclass antibody responses of mice to a/sichuan/2/87 (h3n2) influenza virus surface antigens administered with different carrier or delivery systems by the parenteral route, were carried out. the results obtained were compared with the responses observed following live influenza virus infection, and the protection afforded to these animals by these various preparations determined. infection with live virus elicited early and high levels ... | 1992 | 1642561 |
| in situ detection of autoanti-idiotype antibody-forming cells induced by influenza virus infection. | in situ immunocytochemical-staining methods combined with computer-aided image analysis were employed to examine autoanti-idiotype antibody-forming cell expansion in vivo. autoanti-idiotype antibody-forming cells were demonstrated in the spleens of c57bl/6j (b6) strain mice intranasally infected with the influenza virus a/hong kong/168/(h3n2)[r] x-31. autoanti-idiotype b cells were detected and elevated in spleen tissues after secondary influenza infections compared to normal b6 mice, and were s ... | 1992 | 1728964 |
| impact of influenza virus infection as a cause of pediatric hospitalization. | from winter 1989 to spring 1990, a severe epidemic caused by influenza a (h3n2) and b viruses developed in japan. during the epidemic (december 1989 to february 1990), 244 children were admitted to the pediatric ward of nippon kokan hospital: 53 (21.7%) were hospitalized with influenza virus infection, 22 (9.0%) with rotavirus gastroenteritis, and 17 (7.0%) with respiratory syncytial virus infection. among those with influenza, 24 had type a and 29 had type b. most were young healthy children wi ... | 1992 | 1730904 |
| a novel particulate influenza vaccine induces long-term and broad-based immunity in mice after oral immunization. | the immunogenicity of a novel particulate oral influenza vaccine was examined in terms of antibody response and protection in mice. oral immunization with chicken erythrocytes (crbc) adsorbed with gamma-irradiated influenza a virus induced high levels of immunoglobulin g antibodies and protection in the lung compared with gamma-irradiated virus administered alone or crbc. immunoglobulin a antibodies were the predominant antibodies in nasal washings, and their presence did not correlate with prot ... | 1992 | 1731094 |
| rapid detection of type a influenza viruses with monoclonal antibodies to the m protein (m1) by enzyme-linked immunosorbent assay and time-resolved fluoroimmunoassay. | monoclonal antibodies (mabs) to the m protein (m1) were used in the development of direct detection systems for type a influenza viruses in clinical specimens. optimal detection by an enzyme-linked immunosorbent assay was achieved when mabs were used as capture antibodies and rabbit polyclonal antibodies were used as sandwich antibodies. detection by the enzyme-linked immunosorbent assay required amplification of the virus. direct detection in clinical specimens (nasopharyngeal aspirates) was ac ... | 1991 | 1774253 |
| [a comparative study of the inoculation properties of live recombinant and inactivated influenza vaccines made from strain a/philippines/2/82 (h3n2) in 8- to 15-year-old children]. | this study was carried out to compare reactogenicity, immunogenicity, and efficacy of live attenuated and inactivated influenza vaccines prepared from influenza a/philippines/2/82-like virus strains. schoolchildren of a boarding school of moscow were randomly divided into three groups: (1) vaccinated with a live attenuated vaccine, (2) vaccinated with inactivated influenza vaccine, and (3) given placebo. both vaccines were well tolerated by the children, with practically no severe general or loc ... | 1991 | 1803766 |
| [a comparative study of the protective properties of live recombinant and inactivated influenza vaccines made from strain a/philippines/2/82 (h3n2) in 8- to 15-year-old children]. | a limited controlled comparative study for the evaluation of the epidemiological efficacy of live recombinant and inactivated virion vaccines from a/philippines/2/82-like strains of influenza a (h3n2) virus was carried out in schoolchildren of 8 to 15 years of age. during the influenza epidemic of 1987-1988 caused by influenza a/sichuan/2/87 (h3n2)-like strains and by influenza b virus in 8.2-17% of cases, a statistically significant efficacy index for live influenza vaccine was 1.8 for the labo ... | 1991 | 1803767 |
| [the effect of different factors on the reproduction of influenza viruses and reassortants in cell cultures]. | the influence of the maintenance medium, polyethylene glycol (peg), deae-dextran, and low temperature on reproduction of influenza a, b, and c viruses and their reassortants in diploid and continuous cell cultures was determined. lowering of ph in the maintenance medium to 6.5 was found to decrease reproduction of influenza a (h1n1) and a (h3n2) viruses and increase that of influenza b viruses. treatment of cells with peg solution increased the yield of influenza b and c but not a viruses. howev ... | 1991 | 1803770 |
| [interepidemic influenza in bulgaria based on laboratory research data]. | during the interepidemic periods of 34 years (1955-1988) the national influenza centre of bulgaria with the aid of 11 supporting stations investigated a total of 27240 nasopharyngeal washings and 42530 paired sera of patients with acute respiratory diseases. eighty strains of subtype a (h1n1) influenza virus, 60 strains of subtype a (h2n2), 148 strains of subtype a (h3n2), 3 strains of subtype a (heg2, neg2), 2 strains of subtype a (hsw1n1), 14 strains of type b, and 6 strains of type c were iso ... | 1991 | 1803771 |
| haemagglutination-inhibiting antibodies against influenza a and b in human sera collected from five ecological zones in nigeria. | the prevalence of antibodies to the haemagglutinins of two influenza a subtype, h1n1 and h3n2 and influenza b in sera collected from 1986 to 1988 from persons of different ages and from 10 locations in 5 ecological zones of nigeria was determined. the levels of influenza antibodies in the sera varies with age and ecological zones of the country. a total of 1,022 sera were tested, of which 732 (71.6%) were positive for influenza antibodies. the prevalence of antibodies at titre 1:10 varied betwee ... | 1991 | 1804870 |
| [the evolutionary characteristics of an influenza epidemic in a large urban center (b.) of romania between 1988 and 1990]. | the report presents the peculiar characteristics of influenza epidemics in a big urban centre (b.) of romania, between 1988 and 1990, surveyed by clinical, epidemiological and laboratory methods. among the peculiarities of the epidemics: the low rate of endemic morbidity, the seasonal and preseasonal peaks, the very high implication of infantile population in influenza a(h3n2), a(h1n1) and b virus circulation, as well as the high level of mass specific humoral protection against these viruses. e ... | 1991 | 1814431 |
| isolation and characterization of egg yolk antibodies igy from hens immunized with different influenza virus strains. | a comparison of two precipitation methods of igy from normal hen eggs was made. for method i the precipitation agent is represented by peg 6000, and for method ii by organic solvents. the comparative study of some parameters (protein concentration, ovalbumin content, presence of non-specific inhibitors, paa-gel electrophoresis) shows that method i is more efficient and more convenient than method ii. using this method, we isolated and characterized igy preparations from hens immunized with circu ... | 1991 | 1821163 |
| nosocomial influenza in a general hospital for indigent patients. | surveillance of influenza virus infections was maintained on the medical and pediatric wards of a general hospital serving indigent patients of harris county, texas during the winter of 1987-88. influenza a/sichuan/2/87(h3n2) was the predominant virus during the community epidemic. influenza a(h3n2) virus was isolated from six of 17 adult patients (35%) suspected to have nosocomial infections; two of these patients died of fulminating pneumonia. another patient, admitted with alcoholism and hema ... | 1991 | 1824284 |
| intragenic suppression of a deletion mutation of the nonstructural gene of an influenza a virus. | the influenza a/alaska/77 (h3n2) virus mutant 143-1 is temperature sensitive (ts) due to a spontaneous in-frame 36-nucleotide deletion in the nonstructural (ns) gene segment, which leads to a 12-amino-acid deletion in the ns1 protein. in addition, it has a small-plaque phenotype on mdck cell monolayers. however, phenotypically revertant (i.e., ts+) viruses were isolated readily following replication of the 143-1 virus both in vitro and in vivo. in order to determine the genetic mechanism by whic ... | 1991 | 1830112 |
| [the antigenic characteristics of influenza a viral strains circulating synchronously in 2 separated areas (the czsfr--saint petersburg)]. | a comparative study of the antigenic characteristics of influenza a (h1n1) and a (h3n2) virus strains isolated during the same epidemic season, 1989-1990, in st. petersburg and czsfr was carried out by routine serological methods and by cross-challenge of immunized mice. antigenic differences were found only among serosubtype a (h1n1) strains isolated in different areas. the study was carried out in connection with potential occurrence of influenza epidemic outbreaks from local sources. | 1991 | 1838452 |
| [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 ... | 1991 | 1843236 |
| [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 ... | 1991 | 1858361 |
| 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 ... | 1991 | 1863223 |
| 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 ... | 1991 | 1867007 |
| [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 ... | 1991 | 1870599 |
| 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 ... | 1991 | 1872017 |
| 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 ... | 1991 | 1875195 |
| [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 ... | 1991 | 1882517 |
| 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 ... | 1991 | 1885945 |
| 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 ... | 1991 | 1887669 |