Publications

[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 ...	1991	1896057
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 ...	1991	1897304
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 ...	1991	1897305
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 ...	1991	1898606
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 ...	1991	1898661
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 ...	1991	1898970
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 ...	1991	1899819
update: influenza activity--united states and worldwide, and the composition of the 1991-92 influenza vaccine.		1991	1901134
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. ...	1991	1901364
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 ...	1991	1904085
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 ...	1991	1907034
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 ...	1991	1907999
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 ...	1991	1908510
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 ...	1991	1908605
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 ...	1991	1908881
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 ...	1991	1909052
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 ...	1991	1909739
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 ...	1991	1913813
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 ...	1991	1913823
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, ...	1991	1914615
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 ...	1991	1919440
monovalent sialosides that bind tightly to influenza a virus.		1991	1920363
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 ...	1991	1920428
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 ...	1991	1920429
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 ...	1991	1920529
activity of cd4+ t-cell clones of type 1 and type 2 in generation of influenza virus-specific cytotoxic responses in vitro.	the activity of distinct cd4+ t-helper cell (th) clones in promoting secondary a/pr/8/34/mt.s.(h1n1) (a/pr8) influenza virus-specific, class i-restricted cytotoxic t-lymphocyte (ctl) responses in vitro was examined. cd8+ t cells which had been purified by fluorescence-activated cell sorter from spleen cells of a/pr8-primed mice were used as responders. on their own, purified cd8+ t cells were unable to generate cytotoxic activity upon in vitro culture with a/pr8-infected stimulator cells. signif ...	1991	1920626
some (not all) influenza watchers suggest 'bad season' lies ahead.		1991	1920733
[perimyocarditis in influenza a virus infection].	a 48-year old man was admitted with suspected acute myocardial infarction because of severe precordial pain and monophasic st-elevations in the ecg. the patient's history of an ongoing infection, the localization, extent, and course of the ecg changes as well as the development of a pericardial effusion suggested viral perimyocarditis. the diagnosis was supported by a significant rise of antibodies (seroconversion) against influenza a virus.	1991	1921243
influenza a(h1n1): a widening spectrum?	to study the incidence of h1n1 influenza from 1977 to 1988 in unvaccinated volunteers and the effects of continuing minor antigenic change (antigenic drift) in the virus.	1991	1921782
influenza virus ts61s hemagglutinin is significantly defective in polypeptide folding and intracellular transport at the permissive temperature.	the influenza virus hemagglutinin (ha) temperature-sensitive (ts) mutant, ts61s, contains a nucleotide change in rna segment 4 which leads to an amino acid change at ha1 residue 110 of serine to proline. when ts61s ha is synthesized and maintained at the nonpermissive temperature (39.5 degrees), the ha is defective in transport in the exocytic pathway and is retained in the endoplasmic reticulum (s. nakajima, d. j. brown, m., ueda, k., nakajima, a. suguira, a. k. pattnaik, and d. p. nayak, 1986, ...	1991	1926789
aerosol and intraperitoneal administration of ribavirin and ribavirin triacetate: pharmacokinetics and protection of mice against intracerebral infection with influenza a/wsn virus.	ribavirin is active in vitro but not in vivo against a number of viruses capable of causing encephalitis. ribavirin triacetate (rta), a lipophilic derivative, has been reported to be more effective than ribavirin in protecting animals from encephalitis. by using an influenza a/wsn virus encephalitis model, we demonstrated that rta administered by small-particle aerosol was able to decrease the death rate and increase the time of survival. to determine if this beneficial effect was due to increas ...	1991	1929307
temporal control for translation of influenza virus mrnas.	cdnas for genome rnas of influenza virus a/pr/8/34 were cloned and portions containing the atg initiation codon for translation were inserted into the 5' leader sequence of the chloramphenicol acetyltransferase (cat) gene in a psv2cat vector. in cells that were transfected with a plasmid containing a cdna segment for the early gene and then super-infected with influenza virus, the maximal cat activity was obtained at the early stage of infection. in contrast, a plasmid containing a cdna segment ...	1991	1929878
modification of the cleavage activation of the influenza virus hemagglutinin by site-specific mutagenesis.	factors determining cleavability of influenza virus hemagglutinin which is activated by ubiquitous cellular endoproteases were analysed by carrying out site-directed mutagenesis on the cloned hemaglutinin genes of strains a/fpv/rostock/34 (subtype h7) and a/port chalmers/1/73 (subtype h3). substitutions at the cleavage site of the h7 hemagglutinin indicate that the tetrapeptide arg-x-lys/arg-arg is the minimal consensus sequence recognized by the ubiquitous proteases. the h3 hemagglutinin also b ...	1991	1930091
on the penetration mechanism of influenza viruses.	the envelopes of influenza viruses contain in addition to lipids also two glycoproteins, the hemagglutinin and the neuraminidase, that are responsible for the adsorption, receptor splitting, penetration and budding processes of these viruses. in this article, hypotheses presented in the past with regard to the virus penetration are reconsidered. based on results obtained with the fowl plague virus (influenza a/fpv/rostock/34, h7n1) and mdck-cells, we conclude that a fusion between the viral enve ...	1991	1930099
processing of influenza virus hemagglutinin in insect cells.		1991	1930101
paramyxovirus tropism dependent on host proteases activating the viral fusion glycoprotein.	an essential step in paramyxovirus fusion (f) glycoprotein biosynthesis is the posttranslational endoproteolytic cleavage of the inactive precursor glycoprotein fo by host cell proteases. when the fo possesses a pair or a cluster of basic residues at the cleavage site, cleavage is catalyzed by a ubiquitous protease(s) and the infection is consequently pantropic. when the site is monobasic with a single arginine, cleavage is allowed to occur only by the enzyme(s) expressed in limited tissue types ...	1991	1930102
synthesis and function of influenza a virus glycoproteins.	the surface glycoproteins of influenza a viruses are the viral components first recognized by the immune system of the infected host, and they are the viral proteins first to contact the infecting cell. cleavage of the hemagglutinin (ha) is the presupposition for the uptake and fusion between viral and endosomal membranes at a relatively low ph. if this cleavage does not occur during synthesis and migration within the cell, an external trypsin-like protease has to activate the virus with a non-c ...	1991	1930103
impact of influenza on morbidity in children with cystic fibrosis.	recommendations concerning annual influenza vaccination in children suffering from cystic fibrosis (cf) are not uniform. previous studies have shown that influenza causes a small proportion of episodes of acute respiratory deterioration in cf patients. during the 1989 australian winter, we studied the association between serologically proven influenza infection and acute respiratory morbidity in 20 children with cf. six children were shown to have influenza infection, four with type a and two wi ...	1991	1931225
interaction of influenza virus hemagglutinin with a lipid monolayer. a comparison of the surface activities of intact virions, isolated hemagglutinins, and a synthetic fusion peptide.	in the infectious entry pathway of influenza virus, the low ph of the endosomal compartment induces an irreversible conformational change in influenza virus hemagglutinin, leading to fusion of viral and endosomal membranes. in the current report, we characterized the low-ph-induced activation of hemagglutinin of influenza strain x31 by studying its interaction with a lipid monolayer. the surface activities of virions, of isolated hemagglutinins and its proteolytic fragments, and of a synthetic p ...	1991	1932037
immunological effects of tumor vaccines: iii. influenza virus oncolysates inhibit the tpa induced activation of peripheral blood mononuclear cells.	this paper investigates the effects of tumor vaccines on t cell proliferation induced by 12-0 tetradecanoylphorbol-13-acetate (tpa). viral oncolysate (vo) tumor vaccines containing inactivated influenza virus a significantly inhibited tpa-induced t cell proliferation. in contrast, a control tumor vaccine (co) that contained the same cellular components as vo but lacked influenza virus did not affect the tpa-induced proliferation. these effects were also observed with peripheral blood mononuclear ...	1991	1932617
association between secretor status and respiratory viral illness.	to determine whether non-secretion of blood group antigens is associated with respiratory virus diseases.	1991	1932971
the effects of influenza virus infection on fev1 in asthmatic children. the time-course study.	to study the time-course of influenza-induced asthma, we retrospectively examined fev1 from five days before to ten days after the onset of illness in 20 asthmatic children aged 8 to 12 years with tolerable respiratory symptoms. influenza infection was confirmed by a rise at least fourfold in serum complement fixation titers. fifteen of 20 patients had decrease in fev1 more than 20 percent from baseline during the acute stage. fev1 began to decrease with the onset of illness in the 15 patients w ...	1991	1935277
efficiency of peptides and lipopeptides for in vivo priming of virus-specific cytotoxic t cells.	synthetic peptides and a novel type of lipopeptide vaccine, both containing t cell epitopes recognized by kd-restricted, influenza virus-specific cytotoxic t cells (ctl) were compared in their efficiency to induce virus-specific ctl in vivo. all attempts to induce virus-specific ctl with synthetic peptide (in the absence of adjuvants) failed. however, a latent immunization was observed, resulting in an increased response to the injected peptide seen only after boosting the recipients with immuno ...	1991	1936113
a b cell population that dominates the primary response to influenza virus hemagglutinin does not participate in the memory response.	the early primary b cell response of balb/c mice to the influenza virus a/pr/8/34 (pr8) hemagglutinin (ha) is dominated by b cells that utilize a single v kappa gene in association with one of two closely related vh genes. we have used an anti-idiotypic reagent that recognizes a light chain-associated idiotope (23-1 id) on these antibodies to follow their presence during the anti-ha response. quantitation of 23-1id+ antibodies at different time points during the anti-ha response indicates that t ...	1991	1936117
antiviral activity of some natural and synthetic sugar analogues.	a number of natural and synthetic sugar analogues have been tested for their antiviral activity, using an influenza virus strain as a model. hemagglutinating titres (ha) and cytopathic effect (cpe) were surveyed to estimate the virus production. it was found that introduction of the benzyl group into these sugars generally causes them to become antivirally active. substitution with methyl, acetyl, uridyl and thiocyanyl groups or derivatization with azido, isopropylidene and benzylidene groups we ...	1991	1936265
fluvirucins a1, a2, b1, b2, b3, b4 and b5, new antibiotics active against influenza a virus. iv. taxonomy on the producing organisms.	the morphology, chemotaxonomy, and cultural and physiological characteristics were examined on the five strains of actinomycetes which produce antiviral antibiotics, fluvirucin congeners. all strains have meso-2,6-diaminopimelic acid in the cell wall. four strains, q464-31, l407-5, r359-5 and r516-16, belong to the maduromycetes since they have madurose in the whole cell. the remaining one strain, r869-90, has rhamnose but no madurose, and is a nocardioform actinomycete. these five strains were ...	1991	1938616
detection and identification of human influenza viruses by the polymerase chain reaction.	a series of oligonucleotide primers are described which hybridize to conserved regions of influenza virus cdna and prime dna synthesis in taq polymerase catalyzed amplification reactions (pcr). primers were designed to hybridize as nested pairs and, following a two-step amplification, produce uniquely sized dna fragments diagnostic for viral type and subtype. influenza a and b matrix-protein genes and the influenza c haemagglutinin gene were targets for the type-specific primers. subtype-specifi ...	1991	1939505
influenza a virus infection of macrophages. enhanced tumor necrosis factor-alpha (tnf-alpha) gene expression and lipopolysaccharide-triggered tnf-alpha release.	we have previously shown that infection of macrophages by influenza a virus is capable of priming for a high tnf-alpha production in response to lps. the present study was designed to examine in more detail tnf-alpha gene expression and tnf-alpha protein release of virus-infected, murine pu5-1.8 macrophages in the presence or absence of low and by itself rather inefficient concentrations of lps (10 ng/ml). although influenza a virus infection alone induced a massive tnf-alpha mrna accumulation, ...	1991	1940351
virulence of rimantadine-resistant human influenza a (h3n2) viruses in ferrets.	the influence of rimantadine-resistance mutations on the virulence of human h3n2 viruses in ferrets was examined. the similarities in virulence of the drug-resistant mutants with single amino acid substitutions at three different locations, 27, 30, and 31, within the m2 sequence and their corresponding sensitive wild-type isolates contrasted with differences in virulence between the three pairs of viruses. these data provide further evidence that rimantadine-resistant viruses that emerge during ...	1991	1940477
involvement of the influenza a virus pb2 protein in the regulation of viral gene expression.	to determine the function(s) of the pb2 protein of influenza a virus, six temperature-sensitive (ts) mutants of a/udorn/72 (h3n2) virus, each carrying a ts mutation in the pb2 gene, were analysed for virus rna and protein synthesis. one of the mutants, icrc27, exhibited unique phenotypes and was characterized in detail. at the non-permissive temperature, 40 degrees c, the accumulation of mrna for each genome segment was reduced severely, leading to delayed and reduced synthesis of viral proteins ...	1991	1940863
sequence analysis of the haemagglutinin (ha) of influenza a (h1n1) viruses present in clinical material and comparison with the ha of laboratory-derived virus.	we used the polymerase chain reaction to amplify the ha1 coding region of influenza a (h1n1) viruses present in clinical material from recent cases of influenza in the u.k. previously, we have demonstrated that isolation of human influenza viruses in embryonated hens' eggs selects variants which have amino acid substitutions in their haemagglutinin (ha) clustering around the receptor-binding site. such egg-selected variants are often antigenically distinct from each other and from corresponding ...	1991	1940864
an indian hospital study of viral causes of acute respiratory infection in children.	from sept. 1986 to jan. 1989, a hospital-based study was conducted on 736 children, under 5 years of age, with acute respiratory infection. nasopharyngeal secretions were examined for viruses by culture and by immunofluorescence. viruses were detected in 22% of specimens: respiratory syncytial (5%), parainfluenza (5%), influenza a (4%), influenza b (2%), adenovirus (3%), measles (3%). the highest rates of detection were with patients diagnosed clinically as pneumonia or upper respiratory tract i ...	1991	1941992
rapid antigenic-type replacement and dna sequence evolution of canine parvovirus.	analysis of canine parvovirus (cpv) isolates with a panel of monoclonal antibodies showed that after 1986, most viruses isolated from dogs in many parts of the united states differed antigenically from the viruses isolated prior to that date. the new antigenic type (designated cpv type 2b) has largely replaced the previous antigenic type (cpv type 2a) among virus isolates from the united states. this represents the second occurrence of a new antigenic type of this dna virus since its emergence i ...	1991	1942246
from the centers for disease control. influenza activity--worldwide, 1990-91.		1991	1942390
the herald waves of influenza virus infections detected in sendai and yamagata cities in 1985-1990.	the community surveillance of respiratory virus infections performed during 1985-1987 in sendai and 1988-1990 in yamagata has identified a total of five herald waves of influenza virus infections: a/h3n2 virus infections in 1985 and 1989, a/h1n1 virus infections in 1986 and 1988, and type b virus infections in 1989. to investigate the antigenic and genetic relationships between the herald wave and epidemic strains, influenza a/h1n1 viruses isolated during the 1986 and 1988 herald waves were comp ...	1991	1943849
update: influenza activity--worldwide, 1990-91, and influenza vaccination--united states.	during the 1990-91 influenza season, influenza occurred at relatively low levels throughout much of the world. all reporting countries (except brazil and papua new guinea, which reported epidemic levels) indicated either sporadic cases, small local outbreaks, or regional outbreaks. this report summarizes worldwide influenza activity reported from april through september 1991.	1991	1944118
update: influenza activity--united states, 1991-92.	from late october through november 20, 1991, state health departments reported outbreaks of culture-confirmed influenza a(h3n2) in public schools in texas and a university in tennessee. in addition, alabama, georgia, minnesota, north carolina, ohio, and tennessee reported outbreaks of culture-confirmed influenza a (not subtyped) in schools. in these outbreaks, school absentee rates ranged from 11% to 40%; school closures were reported in ohio and tennessee.	1991	1944132
immunogenicity of trivalent subunit and split influenza vaccines (1989-90 winter season) in volunteers of different groups of age.	trivalent split or subunit influenza vaccines [a/shangai/11/87 (h3n2), a/singapore/6/86 (h1n1) and b/yamagata/16/88] recommended for the 1989-90 winter season and licensed in italy, were administered to 149 volunteers of three different age groups (elderly, middle-aged and young). antibody production was determined in pre- and postvaccination sera by haemagglutinin inhibition test and the results were evaluated as protection and response rates. the split vaccine was more immunogenic than the sub ...	1991	1950094
[the evaluation of the reactogenicity and immunological activity of an inactivated 3-component influenza vaccine with an elevated hemagglutinin concentration in the inoculation dosage].	in this work the reactogenic properties and antigenic potency of inactivated trivalent influenza vaccine, obtained by elution and centrifugation and containing up to 9-11 micrograms of hemagglutinin for influenza viruses a(h1n1) and a(h3n2) and up to 14 micrograms for influenza virus b, were studied. the reactogenicity of the preparation was found to correspond to the regulations. the immunogenic potency characteristics of individual batches of this trivaccine were higher than the immunogenicity ...	1991	1950267
prevention of influenza in high-risk patients: 1991-92 vaccination guidelines.		1991	1951040
emergence and possible transmission of amantadine-resistant viruses during nursing home outbreaks of influenza a (h3n2).	outbreaks of influenza a (h3n2, a/shanghai/11/87-like) occurred in two partially (60% and 79%) vaccinated nursing home populations in january 1988. a retrospective cohort study using chart review was designed to assess the effectiveness of influenza vaccination and amantadine prophylaxis (100 mg per day) in controlling the outbreaks and to determine the amantadine susceptibility of influenza viruses isolated from case-patients. the point estimate of vaccine efficacy in preventing influenza-like ...	1991	1951297
recovery of drug-resistant influenza a virus during therapeutic use of rimantadine.	the therapeutic activity of rimantadine and its relationship to the shedding of drug-resistant influenza a virus were assessed in two randomized, double-blind, placebo-controlled trials involving patients with laboratory-documented influenza a virus (h3n2 subtype) illness of 2 days' duration or less. in a family-based study, rimantadine treatment for 10 days (24 children and adults) was associated with significant decreases in the number of days to a 50% reduction in symptoms (mean difference, 2 ...	1991	1952841
the neutral theory of molecular evolution: a review of recent evidence.	in sharp contrast to the darwinian theory of evolution by natural selection, the neutral theory claims that the overwhelming majority of evolutionary changes at the molecular level are caused by random fixation (due to random sampling drift in finite populations) of selectively neutral (i.e., selectively equivalent) mutants under continued inputs of mutations. the theory also asserts that most of the genetic variability within species at the molecular level (such as protein and dna polymorphism) ...	1991	1954033
translocation of peptides through microsomal membranes is a rapid process and promotes assembly of hla-b27 heavy chain and beta 2-microglobulin translated in vitro.	we have translated major histocompatibility complex (mhc) class i heavy chains and human beta 2-microglobulin in vitro in the presence of microsomal membranes and a peptide from the nucleoprotein of influenza a. this peptide stimulates assembly of hla-b27 heavy chain and beta 2-microglobulin about fivefold. by modifying this peptide to contain biotin at its amino terminus, we could precipitate hla-b27 heavy chains with immobilized streptavidin, thereby directly demonstrating class i heavy chain- ...	1991	1955465
dominant-negative mutants as antiviral agents: simultaneous infection with the cold-adapted live-virus vaccine for influenza a protects ferrets from disease produced by wild-type influenza a.	the attenuated cold-adapted strain of influenza a virus that is a candidate live-virus vaccine suppressed clinical disease in ferrets when given simultaneously with a virulent epidemic strain of influenza a virus. the cold-adapted virus effectively prevented disease, even when the epidemic strain was of a different subtype than the attenuated virus. in this case, ferrets given a mixed inoculum produced antibody to both subtypes in the absence of clinical disease, indicating that both viruses are ...	1991	1955719
intraepidemic variants of influenza virus h3 hemagglutinin differing in the number of carbohydrate side chains.	during the epidemic outbreak in the region of greifswald in the winter 1974/75, we found influenza virus variants which showed differences in the electrophoretic mobility of ha. among the 25 isolates 13 were of slower and 12 of higher mobility. ha1 of 6 isolates was studied by determining the number of the carbohydrate side chains and by direct sequencing of vrna. evidence is presented that variants showing a slower electrophoretic mobility of ha1 had consistently acquired a seventh carbohydrate ...	1991	1958130
an unusual community outbreak of influenza a.	the hong kong h3n2 subtype of influenza a virus appeared in 1968 and since then has caused epidemics of varying degrees of severity. we describe a community outbreak of influenza a h3n2 which occurred in members of a bowls club in an english rural village in late april 1989. the explosive onset, high attack rate (34/41 = 83 per cent) in those exposed, and the clinical presentation initially suggested a toxic or allergic aetiology. twenty-three persons consulted their general practitioners; befor ...	1991	1958413
influenza serosurvey for 1991-1992 season. prevalence of antibody to current influenza virus strains in a 1991 canadian serosurvey.		1991	1959137
control of influenza a outbreaks in nursing homes: amantadine as an adjunct to vaccine--washington, 1989-90.	outbreaks of influenza a virus infection can cause substantial morbidity and mortality among residents of nursing homes. surveillance for the 1991-92 influenza season indicates that the dominant circulating viruses are influenza a (1), for which amantadine hydrochloride is effective for prevention and treatment (2). this report describes the use of amantadine as an adjunct to influenza vaccine for controlling an influenza a(h3n2) outbreak that occurred in a washington nursing home during the 198 ...	1991	1961174
update: influenza activity and vaccine availability--united states, 1991-92.	during the 1991-92 influenza season, widespread influenza-like illness (ili) activity* was first reported in louisiana for the week ending november 9, 1991, and in mississippi the week ending november 16. through november 30, six additional states (alaska, missouri, new york, north carolina, tennessee, and texas) reported widespread activity; 13 (alabama, arkansas, california, florida, georgia, indiana, kansas, kentucky, minnesota, nebraska, new jersey, ohio, and pennsylvania) reported regional ...	1991	1961177
the effect of virus particle size on chemiluminescence induction by influenza and sendai viruses in mouse spleen cells.	suspensions of orthomyxo- and paramyxoviruses are composed of pleomorphic particles ranging from large filaments to small spheres. influenza and sendai viruses were separated according to size by gel filtration and the induction of luminol-dependent chemiluminescence (cl) by particles of similar size was studied in suspensions of mouse spleen cells known to contain phagocytes. cl reflects the generation by the cells of reactive oxygen species. cl induction decreased with particle size for both v ...	1990	1963614
viruses associated with acute lower respiratory tract infections in children from the eastern highlands of papua new guinea (1983-1985).	this study, conducted at goroka hospital from january 1983 to june 1985, examined the viruses identified in nasopharyngeal aspirates (npa) and urines collected from 716 hospitalised children with moderate or severe pneumonia, in npa from 170 children with mild pneumonia treated as outpatients and in npa from a control group of 428 children attending the outpatient department of goroka hospital suffering from minor ailments other than upper or lower respiratory tract infections. one or more virus ...	1990	1963705
inhibitory effect of a new antibiotic, guanine 7-n-oxide, on the replication of several rna viruses.	guanine 7-n-oxide (g-7-ox) was examined for its antiviral activity against 9 viruses based on plaque reduction, neuraminidase activity reduction, a fluorescent antibody technique or elisa. the following viruses were included in the tests: influenza, sendai, simian virus 5 (sv5), respiratory syncytial, western equine encephalitis, japanese encephalitis, vesicular stomatitis, rabies and polio. g-7-ox showed broad anti-rna viral activity against all viruses tested, except for poliovirus. inhibition ...	1990	1964374
[studies of the adaptation of influenza viruses to lowered temperatures of replication. ii. studies in vivo].	swiss white mice were given intranasally suspension of influenza a virus (h3n2) isolated at different period of time and replicated in lowered temperatures in 11 days old chicken embryos. the presence of antigen in lung of animals was detected by if. they were given the virus replicated at 30 degrees c at different rate depending on strain tested. no distinct differences were observed in haemagglutination inhibition antibody level. on the other hand the level of neuraminidase activity inhibiting ...	1990	1964991
evaluation of the toxicity and antiviral activity of carbocyclic 3-deazaadenosine against respiratory syncytial and parainfluenza type 3 viruses in tissue culture and in cotton rats.	the toxicity and antiviral efficacy of carbocyclic 3-deazaadenosine (cc3ado) against respiratory syncytial (rsv) and parainfluenza type 3 (piv3) virus infections were tested in tissue culture and in cotton rats. the mean median efficacious dose (ed50) of cc3ado in hep2 cells against rsv and piv3 was 9 and 14 micrograms/ml, respectively. these values were 85- and 55-fold less than the median inhibitory (toxic) dose (id50) of cc3ado in this cell line (750 micrograms/ml), and similar to values obta ...	1990	1965109
[the incidence of exacerbations in chronic diseases in patients hospitalized with influenza and para-influenza].	a retrospective analysis was made of the case reports of 829 patients admitted to the infectious department with a diagnosis of influenza (592) and parainfluenza (237). in all the patients, the diagnosis was supported serologically with the aid of the hemagglutination inhibition test, with the antibody titer in the serum rising 4-fold and more. in part of the patients the indicated test was used in combination with the immunofluorescence test in studying nasopharyngeal smears, whereas in part of ...	1990	1965617
[respiratory viral infections in young children 1988-1990].	from october 1988 to june 1989 the studies on viral infections of respiratory tract were done in specimens taken from 461 children, aged 0-2 years. similarly to the observations in previous epidemic seasons infections due to rs and parainfluenza type 3 viruses were dominated. these studies included also influenza type c and parainfluenza type 4 viruses with unknown epidemiology in poland. the insignificant role of these infections in small children was estimated according to the low ratio of det ...	1990	1966118
influenza a (h3n2) component of recommended vaccine induces antibody to current virus.		1990	1967480
class ii mhc molecules can use the endogenous pathway of antigen presentation.	models for antigen presentation have divided the world of antigens into two categories, endogenous and exogenous, presented to t cells by class i and class ii major histocompatibility complex (mhc) encoded molecules, respectively. exogenous antigens are though to be taken up into peripheral endosomal compartments where they are processed for binding to class ii mhc molecules. endogenous antigens are either synthesized or efficiently delivered to the cytoplasm before being partially degraded in a ...	1990	1967486
differential sensitivity of human t helper cell pathways by in vitro exposure to cyclosporin a.	cyclosporin a (csa) is a widely used agent for the prevention of tissue allograft rejection in human transplantation. as a result of the recent demonstration that the allospecific th cell response of human pbl can be generated by three distinct pathways of th cell and apc interactions, we investigated the sensitivity of these three th-apc pathways, as well as the th response to recall ag, to different concentrations of csa. pbl from healthy volunteer donors were set up as primary in vitro cultur ...	1990	1969447
increased serum neopterin in patients with hiv-1 infection is correlated with reduced in vitro interleukin-2 production.	recently we have observed that the cd4+ t cell response of peripheral blood mononuclear cells (pbmc) to soluble antigens is the first to be lost in the course of hiv-1 infection followed by the loss of response to hla alloantigens. in this study we compared serum neopterin concentrations of individuals with early stages of hiv-1 infection (stages wr1 and wr2, walter reed staging system) with in vitro interleukin-2 (il-2) production of pbmc in response to stimulation with soluble antigens (influe ...	1990	1969780
modern vaccines. pneumococcus and influenza.		1990	1969994
circumvention of defective cd4 t helper cell function in hiv-infected individuals by stimulation with hla alloantigens.	pbl from approximately 50% of asymptomatic individuals infected with hiv have been previously demonstrated to exhibit defective in vitro th function that is selective for influenza a virus (flu), but not for hla alloantigens (allo). in this report, we have further studied hiv+ individuals with this selective th defect, and demonstrate that defective in vitro ctl responses to flu can be restored by costimulation with flu + allo. in contrast, hiv+ patients who have lost th responses to allo were u ...	1990	1970348
analysis of the role of leukocyte function-associated antigen-1 in activation of human influenza virus-specific t cell clones.	the role of leukocyte function-associated ag-1 (lfa-1) in intercellular adhesion is well documented. previously, we demonstrated that the lfa-1 molecule (cd11a/cd18) can also regulate the induction of proliferation of peripheral blood t cells. in these studies, we observed opposite effects of antibodies against cd11a (lfa-1-alpha-chain) or cd18 (lfa-1-beta-chain). here, we determined the effects of anti-cd11a and anti-cd18 mab on proliferation of cloned influenza virus-specific t cells. anti-cd1 ...	1990	1970349
the influence of endogenous hypocorticism on the replication of influenza virus in the mouse lungs and the production of specific antibodies.	the replication of pathogenic influenza virus a/pr/8/34 in the lungs and the synthesis of virus-neutralizing (vn) and haemagglutination-inhibition (hi) antibodies has been studied in mice with endogenous hypocorticism induced by a bilateral adrenalectomy. the adrenalectomized mice appeared to be more susceptible to influenza infection as compared to the mock-operated ones. this was evident from earlier deaths and higher death rate in mice inoculated with 50 eid50, 1000 eid50, and 6000 eid50 of t ...	1990	1975723
[the role of disorders in the central mechanisms of neurohumoral regulation in the outcome of a viral infection (experimental influenza)].		1990	1980243
primary structure of the gene coding for the haemagglutinin of influenza virus a/leningrad/385/80(h3n2): detection of a point mutation responsible for the antigenic drift.	primary structure of the gene coding for haemagglutinin (ha-gene) of influenza virus a/leningrad/385/80(h2n2) isolated during the epidemics of influenza in leningrad in 1980 was determined. the close relationship of ha gene of this virus to the corresponding gene of the virus a/bangkok/1/79(h3n2) was confirmed. it was shown that a single mutation in an antigenic site (the change from isoleucine to leucine at position 51 of ha1 gene) caused an antigenic drift. one silent mutation was detected (nu ...	1990	1980394
antiviral activities of pyrimidine nucleoside analogues: some structure--activity relationships.	seventeen nucleoside derivatives (derived from arabinosylcytosine, resp. cytidine, 5-fluorouracil and uracil) were tested by agar-diffusion plaque-inhibition test for their antiviral activity with herpes simplex, vaccinia, fowl plague, newcastle disease and western equine encephalomyelitis viruses. the highest antiviral activity against dna viruses exhibited arabinosylcytosine, n4-acylarabinosylcytosines, arabinosylthiouracil, cyclocytidine and its 5'-chloroderivative. rna viruses were inhibited ...	1990	1981442
influenza virus detection in clinical specimens.	the authors compared the results of influenza a (h1n1) and influenza a (h3n2) virus detection in nasopharyngeal swabs from flu patients by molecular hybridization (mh), elisa, virus isolation and seroconversion. using the immunofluorescence (if) technique influenza virus was detected in cell suspensions from the first chick embryo passage. altogether 63 swabs from various epidemic seasons were separated into 3 groups according to specimen sampling and storage. it was shown that influenza virus r ...	1990	1981455
radioimmunoassay and oligonucleotide mapping of a/hswln1 influenza viruses isolated from humans and animals.		1990	1981460
interleukin-1-inhibitor activity induced by respiratory syncytial virus: abrogation of virus-specific and alternate human lymphocyte proliferative responses.	respiratory syncytial virus (rsv) infection has been shown to induce human mononuclear leukocyte (mnl) production of net interleukin-1 (il-1)-inhibitor activity. in the current studies of il-1-inhibitor effects, rsv-exposed cells were compared with autologous mnl that were sham-exposed or exposed to inactivated rsv or influenza virus (which induces net il-1 activity and commonly elicits effective homotypic immunity). exposure of mnl to influenza virus or inactivated rsv resulted in increased exp ...	1991	1984478
the n2 neuraminidase of human influenza virus has acquired a substrate specificity complementary to the hemagglutinin receptor specificity.	a survey of 10 human influenza a viruses of the n2 serotype, isolated between 1957 and 1987, has revealed a drift in neuraminidase linkage specificity. while the earliest n2 strains examined exhibit strict specificity for cleavage of the neuac alpha 2,3gal sequence, n2 isolates from 1967 to 1968 also show limited activity towards the neuac alpha 2,6gal linkage. in strains isolated in 1972 and later, the n2 neuraminidase has approximately equal activity towards both types of linkages. the neuac a ...	1991	1984642
retarded processing of influenza virus hemagglutinin in insect cells.	when expressed in spodoptera frugiperda cells by a baculovirus vector, the hemagglutinin of fowl plague virus has been found to contain palmitic acid in covalent hydroxylamine-sensitive linkage, indicating that these cells have the capacity to acylate foreign proteins at cysteine residues. centrifugation on sucrose density gradients and immune precipitation with conformation-specific antibodies were used to compare trimerization of the hemagglutinin in insect cells and in fowl plague virus-infec ...	1991	1984645
interferon-induced proteins: identification of mx proteins in various mammalian species.	mx protein controls influenza virus pathogenicity in mice in vivo. it is an abundant protein synthesized in response to interferon-alpha/beta. searches for homolog proteins in various animal species have been conducted using several methods: (1) radioactive labeling of proteins induced by interferon and analysis by 2-d gel electrophoresis, (2) immunoprecipitation, (3) protoblot-elisa analysis of cell-protein extracts, and (4) immunostaining of fixed cells. all mammalian species tested so far (in ...	1991	1984648
the genes associated with trans-dominance of the influenza a cold-adapted live virus vaccine.	segment 7 (m) of the cold-adapted live influenza a virus vaccine plays a primary role in the ability of this virus to interfere with the replication of wild-type influenza a viruses. this conclusion is based on several lines of evidence. single gene reassortant viruses derived by crossing influenza a/ann arbor/6/60 (h2n2) cold-adapted donor virus with an epidemic wild-type strain, a/korea/1/82 (h3n2), were tested for their ability to interfere with wild-type parental virus in the madin-darby lin ...	1991	1984670
transport of incoming influenza virus nucleocapsids into the nucleus.	upon penetration of the influenza virus nucleocapsid into the host cell cytoplasm, the viral rna and associated proteins are transported to the nucleus, where viral transcription and replication occur. by using quantitative confocal microscopy, we have found that over half of cell-associated nucleoprotein (np) entered the nucleus with a half time of 10 min after penetration into cho cells. microinjection and immunoelectron microscopy experiments indicated that the np entered the nucleus through ...	1991	1985199
two signals mediate nuclear localization of influenza virus (a/wsn/33) polymerase basic protein 2.	polymerase basic protein 2 (pb2), a component of the influenza virus polymerase complex, when expressed alone from cloned cdna in the absence of other influenza virus proteins, is transported into the nucleus. in this study, we have examined the nuclear translocation signal of pb2 by making deletions and mutations in the pb2 sequence. our studies showed that two distant regions in the polypeptide sequence were involved in the nuclear translocation of pb2. in one region, four basic residues (k-73 ...	1991	1985200
reassociation with beta 2-microglobulin is necessary for db class i major histocompatibility complex binding of an exogenous influenza peptide.	a synthetic peptide corresponding to residues 365-380 of the influenza nucleoprotein (np365-380) has been previously shown to associate with class i major histocompatibility complex-encoded molecules and to stimulate cytotoxic t lymphocytes [townsend, a. r. m., rothbard, j., gotch, f. m., bahadur, g., wraith, d. & mcmichael, a. j. (1986) cell 44, 959-968]. we find that intact db class i heterodimers on the cell surface are unreceptive to binding this antigen. however, np365-380 readily associate ...	1991	1986378
antiviral drug therapy.	major advances in molecular virology have led to the development of new antiviral compounds. these drugs include ribavirin, used in the treatment of severe respiratory syncytial virus infection in children; amantadine, used in the prophylaxis and treatment of influenza a infection; acyclovir, used in a variety of herpesvirus infections, including primary gingivostomatitis, genital herpes and herpes zoster; ganciclovir, used in the treatment of retinitis due to cytomegalovirus, and zidovudine, us ...	1991	1986488
attachment of influenza a virus to ferret tracheal epithelium at different maturational stages.	influenza virus attaches primarily to ciliated cells in mature airways epithelium. this process is mediated by a viral envelope glycoprotein (hemagglutinin) that binds to sialic acid-containing receptors in the apical membrane of host cells. the purpose of this study was to determine the cellular distribution of these receptors as a function of tracheal epithelial maturation in the ferret, which is susceptible to influenza virus infection at all ages and undergoes postnatal ciliation. to assay f ...	1991	1986780