| anti-influenza virus activities of flavonoids from the medicinal plant elsholtzia rugulosa. | elsholtzia rugulosa (lamiaceae), a common chinese herb, is widely used in the treatment of cold and fever. in order to elucidate the action mechanism and the active principles from the plant against anti-influenza virus, the influenza virus neuraminidase (na) activity assay and in vitro antiviral activity assay were established, and the isolation of the active principles was guided by na activity. finally, 5 active constituents were obtained, namely apigenin ( 1), luteolin ( 2), apiin ( 3), galu ... | 2008 | 18553272 |
| streptococcus suis type 2 culture supernatant enhances the infection ability of the swine influenza virus h3 subtype in mdck cells. | swine influenza virus and streptococcus suis type 2 often occur as a clinical coinfection in pigs, the syndrome of which is more serious than the virus or bacterium sole infection. streptococcus suis type 2 can produce extracellular proteases, which may cleave hemagglutinin to enhance the infection ability of swine influenza virus. the current study investigated whether extracellular proteolytic culture supernatant of streptococcus suis type 2, isolated from jiangsu, enhanced the infection abili ... | 2008 | 18557523 |
| development of reverse transcription loop-mediated isothermal amplification for rapid detection of h9 avian influenza virus. | reverse transcription loop-mediated isothermal amplification (rt-lamp) is a unique gene amplification method that can be completed within 45 min at 63 degrees c. in this study, rt-lamp was used to develop a rapid and sensitive laboratory diagnostic system for the h9 subtype of avian influenza virus (aiv). the experiment results from the reference strains demonstrated that the established rt-lamp sensitivity was 10-fold higher than that of rt-pcr, with the detection limit of 10 copies per reactio ... | 2008 | 18572258 |
| phylogenetic analysis of swine influenza viruses recently isolated in korea. | several influenza a viral subtypes were isolated from pigs during a severe outbreak of respiratory disease in korea during 2005 and 2006. they included a classical swine h1n1 subtype, two swine-human-avian triple-recombinant h1n2 subtypes, and a swine-human-avian triple-recombinant h3n2 subtype. in the current study, genetic characterization to determine the probable origin of these recent isolates was carried out for the first time. phylogenetic analysis indicated that all the recent korean iso ... | 2008 | 18574682 |
| influenza virus protecting rna: an effective prophylactic and therapeutic antiviral. | another influenza pandemic is inevitable, and new measures to combat this and seasonal influenza are urgently needed. here we describe a new concept in antivirals based on a defined, naturally occurring defective influenza virus rna that has the potential to protect against any influenza a virus in any animal host. this "protecting rna" (244 rna) is incorporated into virions which, although noninfectious, deliver the rna to those cells of the respiratory tract that are naturally targeted by infe ... | 2008 | 18579602 |
| comparison of the clinical effectiveness of oseltamivir and zanamivir against influenza virus infection in children. | we compared the clinical effectiveness of oseltamivir and zanamivir in children with influenza a (h1n1) virus, influenza a (h3n2) virus, and influenza b virus infections. | 2008 | 18582202 |
| [phylogenetic analysis of human/swine/avian gene reassortant h1n2 influenza a virus isolated from a pig in china]. | our aim in this study was to determine the genetic characterization and probable origin of the h1n2 swine influenza virus (a/swine/guangxi/13/2006) (sw/gx/13/06) from lung tissue of a pig in guangxi province, china. | 2008 | 18590231 |
| comparison of three serological assays to determine the cross-reactivity of antibodies from eight genetically diverse u.s. swine influenza viruses. | swine influenza virus is an economically important pathogen to the u.s. swine industry. new influenza subtypes and isolates within subtypes with different genetic and antigenic makeup have recently emerged in u.s. swineherds. as a result of the emergence of these new viruses, diagnosticians' ability to accurately diagnose influenza infection in pigs and develop appropriate vaccine strategies has become increasingly difficult. the current study compares the ability of subtype-specific commercial ... | 2008 | 18599846 |
| seasonal inactivated influenza virus vaccines. | inactivated influenza virus vaccines are the primary modality used for prevention of influenza. a system of annual identification of new strains causing illnesses, selections for vaccines, chick embryo growth, inactivation, processing, packaging, distribution and usage has been in place for decades. current vaccines contain 15 microg of the ha of an a/h1n1, a/h3n2 and b strain and are given parenterally to induce serum anti-ha antibody for prevention of subsequent infection and illness from natu ... | 2008 | 18602728 |
| antibody response to tetravalent influenza subunit vaccine in patients infected with human immunodeficiency virus type 1. | the capacity of patients infected with human immunodeficiency virus (hiv) to develop an adequate antibody response to influenza vaccination in relation to the cd4 cell count has been studied in a prospective study. a total of 73 subjects (54 hiv-infected patients and 19 healthy control persons) were vaccinated with influenza subunit vaccine containing 15 mug hemagglutinin of each of the following strains: a/beijing/353/89(h3n2), a/singapore/6/86(h1n1), b/panama/45/90, and b/beijing/1/87. hemaggl ... | 1996 | 18611709 |
| [construction and immunogenicity analysis of antigenic epitopes of swine influenza virus]. | several antigen epitopes were designed according to the sequences of swine influenza virus hemagglutinin (ha) genes and lined with the interval. the gene was amplified by pcr and sub cloned into pet30a (+) vector. the fusion protein was expressed in e. coli bl21 (de3) by induced with iptg and purified by affinity chromatography. the molecular weight of the protein was about 20 kd in sds-page. immunological activity of the fusion protein was analyzed by western blot. the results showed that the f ... | 2008 | 18616184 |
| domestic pigs have low susceptibility to h5n1 highly pathogenic avian influenza viruses. | genetic reassortment of h5n1 highly pathogenic avian influenza viruses (hpai) with currently circulating human influenza a strains is one possibility that could lead to efficient human-to-human transmissibility. domestic pigs which are susceptible to infection with both human and avian influenza a viruses are one of the natural hosts where such reassortment events could occur. virological, histological and serological features of h5n1 virus infection in pigs were characterized in this study. two ... | 2008 | 18617994 |
| outbreaks of influenza a among nonvaccinated healthcare workers: implications for resource-limited settings. | we identified 3 outbreaks of influenza a (attack rates, 18%-24%) among thai healthcare workers in intensive care units. all outbreaks were epidemiologically linked to an index patient with pneumonia due to influenza a virus (subtype h3n2). the investigations of these outbreaks incurred costs that exceeded the estimated costs of healthcare worker influenza vaccination by more than 10-fold. | 2008 | 18624648 |
| surveillance for neuraminidase inhibitor resistance among human influenza a and b viruses circulating worldwide from 2004 to 2008. | the surveillance of seasonal influenza virus susceptibility to neuraminidase (na) inhibitors was conducted using an na inhibition assay. the 50% inhibitory concentration values (ic(50)s) of 4,570 viruses collected globally from october 2004 to march 2008 were determined. based on mean ic(50)s, a(h3n2) viruses (0.44 nm) were more sensitive to oseltamivir than a(h1n1) viruses (0.91 nm). the opposite trend was observed with zanamivir: 1.06 nm for a(h1n1) and 2.54 nm for a(h3n2). influenza b viruses ... | 2008 | 18625765 |
| structure-activity relationship of flavonoids as influenza virus neuraminidase inhibitors and their in vitro anti-viral activities. | flavonoids are polyphenolic compounds that widely exist in plant kingdom, and the structure-activity relationship (sar) of 25 flavonoids was studied on neuraminidase (na) activity of influenza virus. three typical influenza virus strains a/pr/8/34 (h1n1), a/jinan/15/90 (h3n2), and b/jiangshu/10/2003 were used as the source of nas, the average of ic(50)s of these compounds on these nas was used in the sar analysis. the order of potency for na inhibition was as follows: aurones>flavon(ol)es>isofla ... | 2008 | 18640042 |
| seasonality of influenza a(h3n2) virus: a hong kong perspective (1997-2006). | the underlying basis for the seasonality of influenza a viruses is still uncertain. phylogenetic studies investigated this phenomenon but have lacked sequences from more subtropical and tropical regions, particularly from southeast asia. | 2008 | 18648550 |
| influenza guideline for south africa--update 2008. | objective: the south african thoracic society, in conjunction with interested stakeholders, published a guideline for influenza management in adults in 1999. this year the south african thoracic society (sats) identified the need to revise that guideline for the following reasons: * to indicate the viral strains that are to be incorporated into the vaccine for the 2008 season * to add important new data regarding treatment of influenza * to add a section on influenza in children * to clarify iss ... | 2008 | 18652399 |
| an improved embryonated chicken egg model for the evaluation of antiviral drugs against influenza a virus. | influenza is a serious global public health problem and an economic burden. with the continual emergence of new influenza a virus strains, new antiviral drugs are needed urgently. in this study, an improved embryonated chicken egg model for evaluating antiviral activity against influenza a virus was developed. in the model, the influenza a virus was injected into the allantoic cavity and ribavirin was injected into the albumen of the egg. the levels of influenza a virus in the allantoic fluid wa ... | 2008 | 18652846 |
| modeling amantadine treatment of influenza a virus in vitro. | we analyzed the dynamics of an influenza a/albany/1/98 (h3n2) viral infection, using a set of mathematical models highlighting the differences between in vivo and in vitro infection. for example, we found that including virion loss due to cell entry was critical for the in vitro model but not for the in vivo model. experiments were performed on influenza virus-infected mdck cells in vitro inside a hollow-fiber (hf) system, which was used to continuously deliver the drug amantadine. the hf system ... | 2008 | 18653201 |
| adjustment of receptor-binding and neuraminidase substrate specificities in avian-human reassortant influenza viruses. | balanced action of hemagglutinin (ha) and neuraminidase (na) is an important condition of influenza virus efficient replication, but a role of ha and na specificities at oligosaccharide level in maintaining such a balance remains poorly studied. avian virus ha binds exclusively and na digests efficiently alpha2-3-sialylated carbohydrate chains, while human virus ha interacts with alpha2-6 chains and low-active na cleaves both alpha2-3- and alpha2-6-sialosides. reassortment between viruses leadin ... | 2009 | 18661232 |
| seroprevalence and risk factors for influenza a viruses in pigs in peninsular malaysia. | following a series of h5n1 cases in chickens and birds in a few states in malaysia, there was much interest in the influenza a viruses subtypes that circulate among the local pig populations. pigs may act as a mixing vessel for avian and mammal influenza viruses, resulting in new reassorted viruses. this study investigated the presence of antibodies against influenza h1n1 and h3n2 viruses in pigs from peninsular malaysia using herdcheck swine influenza h1n1 and h3n2 antibody test kits. at the sa ... | 2008 | 18667027 |
| the role of neutrophils in the upper and lower respiratory tract during influenza virus infection of mice. | neutrophils have been shown to play a role in host defence against highly virulent and mouse-adapted strains of influenza virus, however it is not clear if an effective neutrophil response is an important factor moderating disease severity during infection with other virus strains. in this study, we have examined the role of neutrophils during infection of mice with influenza virus strain hkx31, a virus strain of the h3n2 subtype and of moderate virulence for mice, to determine the role of neutr ... | 2008 | 18671884 |
| [generation of neutralizing recombinant human antibodies for targeting highly pathogenic avian influenza a (h5n1) virus]. | two human fab antibodies against avian influenza a (h5n1) virus were obtained by panning a h5n1 patient-derived antibody phage library using purified virions of the h5n1 patient isolate a/anhui/1/2005 and ha protein of the h5n1 reference viruse a/viet nam/1203/2004. after testing the binding properties and antiviral function to h5n1 virus, the selected fab antibodies were converted to full human igg antibodies with recombinant baculovirus/insect cell system. both mabs, avfluigg01 and avfluigg03, ... | 2008 | 18683551 |
| oseltamivir-resistant influenza a viruses are transmitted efficiently among guinea pigs by direct contact but not by aerosol. | influenza viruses resistant to the neuraminidase (na) inhibitor oseltamivir arise under drug selection pressure both in vitro and in vivo. several mutations in the active site of the viral na are known to confer relative resistance to oseltamivir, and influenza viruses with certain oseltamivir resistance mutations have been shown to transmit efficiently among cocaged ferrets. however, it is not known whether na mutations alter aerosol transmission of drug-resistant influenza virus. here, we demo ... | 2008 | 18684820 |
| gene expression analysis of host innate immune responses during lethal h5n1 infection in ferrets. | how viral and host factors contribute to the severe pathogenicity of the h5n1 subtype of avian influenza virus infection in humans is poorly understood. we identified three clusters of differentially expressed innate immune response genes in lungs from h5n1 (a/vietnam/1203/04) influenza virus-infected ferrets by oligonucleotide microarray analysis. interferon response genes were more strongly expressed in h5n1-infected ferret lungs than in lungs from ferrets infected with the less pathogenic h3n ... | 2008 | 18684821 |
| prevention and control of influenza: recommendations of the advisory committee on immunization practices (acip), 2008. | this report updates the 2007 recommendations by cdc's advisory committee on immunization practices (acip) regarding the use of influenza vaccine and antiviral agents (cdc. prevention and control of influenza: recommendations of the advisory committee on immunization practices [acip]. mmwr 2007;56[no. rr-6]). the 2008 recommendations include new and updated information. principal updates and changes include 1) a new recommendation that annual vaccination be administered to all children aged 5--18 ... | 2008 | 18685555 |
| replication and transmission of h9n2 influenza viruses in ferrets: evaluation of pandemic potential. | h9n2 avian influenza a viruses are endemic in poultry of many eurasian countries and have caused repeated human infections in asia since 1998. to evaluate the potential threat of h9n2 viruses to humans, we investigated the replication and transmission efficiency of h9n2 viruses in the ferret model. five wild-type (wt) h9n2 viruses, isolated from different avian species from 1988 through 2003, were tested in vivo and found to replicate in ferrets. however these viruses achieved mild peak viral ti ... | 2008 | 18698430 |
| a new and rapid genotypic assay for the detection of neuraminidase inhibitor resistant influenza a viruses of subtype h1n1, h3n2, and h5n1. | the neuraminidase of influenza viruses is the target of the inhibitors oseltamivir and zanamivir. recent reports on influenza viruses with reduced susceptibility to neuraminidase inhibitors (nai) are a cause for concern. several amino acid substitutions, each as a consequence of one single nucleotide mutation, are known to confer resistance to nai. an increase of nai-resistant viruses appears to be likely as a result of a wider application of nai for treatment and prophylaxis of seasonal influen ... | 2008 | 18725246 |
| molecular epidemiology of a/h3n2 and a/h1n1 influenza virus during a single epidemic season in the united states. | to determine the spatial and temporal dynamics of influenza a virus during a single epidemic, we examined whole-genome sequences of 284 a/h1n1 and 69 a/h3n2 viruses collected across the continental united states during the 2006-2007 influenza season, representing the largest study of its kind undertaken to date. a phylogenetic analysis revealed that multiple clades of both a/h1n1 and a/h3n2 entered and co-circulated in the united states during this season, even in localities that are distant fro ... | 2008 | 18725925 |
| [epidemic strains influenza viruses a and b in the 2005-2006 season in russia]. | investigations indicated that the epidemic upsurge of influenza morbidity in the 2005-2006 season in russia was caused by the active circulation of influenza viruses a and b. the center for ecology and epidemiology of influenza, d. i. ivanovsky institute of virology, russian academy of medical sciences, studied 182 epidemic strains. a hundred and thirteen influenza viruses a(h3n2) were similar to the reference a/california/07/2004 or were its antigenic variants. thirteen influenza virus a(h1n1) ... | 2008 | 18756810 |
| epidemiological and virological assessment of influenza activity in europe, during the 2006-2007 winter. | influenza surveillance in europe is based on influenza surveillance networks that cooperate and share information through the european influenza surveillance scheme (eiss). eiss collected clinical and virological data on influenza in 33 countries during the 2006-2007 winter. influenza activity started around 1 january and first occurred in greece, scotland and spain. it then moved gradually across europe from south to north and lasted until the end of march. in 29 out of 33 countries, the consul ... | 2008 | 18761888 |
| [molecular analyses of human influenza viruses. circulation of new variants since 1995/96]. | the evolution of influenza viruses is increasingly pursued by molecular analyses that complement classical methods. the analyses focus on the two surface proteins hemagglutinin (ha) and neuraminidase (na) which determine the viral antigenic profile. influenza a(h3n2) viruses are exceptionally variable, so that usually at least two virus variants cocirculate at the same time. together with influenza b viruses they caused approximately 90% of influenza virus infections in germany during the last 1 ... | 2008 | 18773168 |
| protection against mouse and avian influenza a strains via vaccination with a combination of conserved proteins np, m1 and ns1. | experimental data accumulated over more than a decade indicate that cross-strain protection against influenza may be achieved by immunization with conserved influenza proteins. at the same time, the efficacy of immunization schemes designed along these lines and involving internal influenza proteins, mostly np and m1, has not been sufficient. | 2007 | 18784792 |
| seroprevalence and genetic evolutions of swine influenza viruses under vaccination pressure in korean swine herds. | an overall 8,427 total of blood samples collected from growing to finishing pigs were submitted for diagnosis of swine influenza virus infection between january 2002 and december 2006. sera from 2002 to 2005 were examined for antibodies against four different swine influenza subtypes using the hemagglutination inhibition test to investigate seroprevalence rates by natural infection in korean swine herds while nasal swabs and lung tissue samples were used for viral isolation. the natural infectio ... | 2008 | 18789984 |
| prevalence of avian influenza viruses, borrelia garinii, mycobacterium avium, and mycobacterium avium subsp. paratuberculosis in waterfowl and terrestrial birds in slovakia, 2006. | the prevalence of borrelia, mycobacteria and avian influenza virus (aiv) infections, together with the distribution of different aiv subtypes, was studied in migratory waterfowl and terrestrial birds trapped in three localities in slovakia during 2006. samples obtained from waterfowl captured in the senianske ponds area of eastern slovakia showed the highest diversity of aiv isolates. a total of 13 different subtypes were detected in 19 samples from this location (h1n2, h2n2, h3n2, h6n6, h7n6, h ... | 2008 | 18798030 |
| role of viral hemagglutinin glycosylation in anti-influenza activities of recombinant surfactant protein d. | surfactant protein d (sp-d) plays an important role in innate defense against influenza a viruses (iavs) and other pathogens. | 2008 | 18811961 |
| high-throughput screening of a 100,000-compound library for inhibitors of influenza a virus (h3n2). | using a highly reproducible and robust cell-based high-throughput screening (hts) assay, the authors screened a 100,000-compound library at 14- and 114-microm compound concentration against influenza strain a/udorn/72 (h3n2). the "hit" rates (>50% inhibition of the viral cytopathic effect) from the 14- and 114-microm screens were 0.022% and 0.38%, respectively. the hits were evaluated for their antiviral activity, cell toxicity, and selectivity in dose-response experiments. the screen at the low ... | 2008 | 18812571 |
| compatibility among polymerase subunit proteins is a restricting factor in reassortment between equine h7n7 and human h3n2 influenza viruses. | reassortment is an important driving force for influenza virus evolution, and a better understanding of the factors that affect this process could improve our ability to respond to future influenza pandemics and epidemics. to identify factors that restrict the generation of reassortant viruses, we cotransfected human embryonic kidney cells with plasmids for the synthesis of viral rnas of both a/equine/prague/1/56 (prague; h7n7) and a/yokohama/2017/03 (yokohama; h3n2) viruses together with the su ... | 2008 | 18815312 |
| universal influenza vaccination and live attenuated influenza vaccination of children. | influenza is an uncontrolled epidemic disease that is vaccine preventable. each winter the peak of medically attended acute respiratory illness coincides with the peak of influenza virus activity. the anatomy of an urban influenza epidemic is presented highlighting the role of children in the spread of influenza. the efficacy and safety of the live attenuated influenza vaccine (laiv) for children are documented and the indirect effectiveness (herd protection) of vaccinating schoolchildren is dem ... | 2008 | 18820568 |
| experimental evolution of human influenza virus h3 hemagglutinin in the mouse lung identifies adaptive regions in ha1 and ha2. | the genetic basis for virulence and host switching in influenza a viruses (fluav) is largely unknown. because the hemagglutinin (ha) protein is a determinant of these properties, ha evolution was mapped in an experimental model of mouse lung adaptation. variants of prototype a/hong kong/1/68 (h3n2) (wild-type [wt] hk) human virus were selected in both longitudinal and parallel studies of lung adaptation. mapping of ha mutations found in 11 independently derived mouse-adapted populations of wt hk ... | 2008 | 18829764 |
| emergence of amantadine-resistant h3n2 avian influenza a virus in south korea. | we found a relatively high frequency of unique amantadine-resistant h3n2 and h9n2 avian influenza viruses (val27ile on m2 protein) isolated from live poultry markets in south korea and confirmed that a val27ile single substitution in the m2 protein is enough to acquire the amantadine resistance phenotype by using reverse-genetically created human-avian reassortant viruses. | 2008 | 18845822 |
| positive selection operates continuously on hemagglutinin during evolution of h3n2 human influenza a virus. | it has been proposed that antigenic evolution of hemagglutinin 1 (ha1) for h3n2 human influenza a virus was punctuated. in the population genetic analysis, however, it was controversial whether positive selection operated on ha1 in a punctuated manner for the branches of the phylogenetic tree where transitions to new antigenic clusters occurred (c branches), or continuously. in the molecular evolutionary analysis, positive selection was detected for the trunk (t) branches but the relationship be ... | 2008 | 18848975 |
| phylogenic analysis of reassorted avian influenza viruses isolated from korean domestic ducks from 2005 to 2007. | ducks have been regarded as animals that can perpetuate most avian influenza viruses since they generally do not show the clear clinical signs such as death and reduced body weight when they are infected. here, we characterized two h3n2 and one h3n6 avian influenza viruses isolated from ducks on the local farms in korea from 2005 to 2007. genetic analysis of these viruses showed that most segments of isolates except np genes belonged to eurasian lineage. np genes of two h3n2 isolates, a/duck/kor ... | 2009 | 18850263 |
| synthesis, antioxidative and antiviral activity of hydroxycinnamic acid amides of thiazole containing amino acid. | the synthesis and the biological (antioxidant and antiviral) activities of novel hydroxycinnamic acid amides of a thiazole containing tfa.valine-4-carboxylic acid ethyl ester are reported. the amides have been synthesized from p-coumaric, ferulic and sinapic acids with the corresponding tfa.valine-thiazole-4-carboxylic acid ethyl ester using the coupling reagent n-ethyl-n'-(3-dimethylaminopropyl) carbodiimide hydrochloride (edc) and 4-(dimethylamino) pyridine (dmap) as a catalyst. the antioxidan ... | 2009 | 18853101 |
| [influenza season 2007/'08 in the netherlands: antigenic variation, oseltamivir resistance and vaccine composition for the 2008/'09 season]. | the first signs of influenza activity during the 2007/'08 influenza season in the netherlands were sporadic isolations of influenza viruses between week 40 and week 52 of 2007. the frequency of virus isolations and clinical influenza activity increased after week 1 of 2008 and peaked around week 9. in this week, 7.2 patients with influenza-like illness were recorded per 10,000 inhabitants. the influenza epidemic was caused primarily by influenza a/h1n1 viruses and influenza b viruses. two antige ... | 2008 | 18856032 |
| oseltamivir is adequately absorbed following nasogastric administration to adult patients with severe h5n1 influenza. | in the absence of a parenteral drug, oral oseltamivir is currently recommended by the who for treating h5n1 influenza. whether oseltamivir absorption is adequate in severe influenza is unknown. we measured the steady state, plasma concentrations of nasogastrically administered oseltamivir 150 mg bid and its active metabolite, oseltamivir carboxylate (oc), in three, mechanically ventilated patients with severe h5n1 (male, 30 yrs; pregnant female, 22 yrs) and severe h3n2 (female, 76 yrs). treatmen ... | 2008 | 18923671 |
| limited susceptibility and lack of systemic infection by an h3n2 swine influenza virus in intranasally inoculated chickens. | chickens were intranasally inoculated with the swine influenza virus (siv) a/swine/nc/307408/04 (h3n2) (nc/04 siv) to determine the infectivity of a north american siv for chickens, as well as the possibility of chicken meat serving as a transmission vehicle for siv. white leghorn (wl) layer-type chickens were used for initial pathotyping and infectivity tests, and a more comprehensive intranasal pathogenesis study was done with white plymouth rock (wpr) broiler-type chickens. none of the nc/04 ... | 2008 | 18939642 |
| ubiquitous reassortments in influenza a viruses. | the influenza a virus is a negative-stranded rna virus composed of eight segmented rna molecules, including polymerases (pb2, pb1, pa), hemagglutinin (ha), nucleoprotein (np), neuraminidase (na), matrix protein (mp), and nonstructure gene (ns). the influenza a viruses are notorious for rapid mutations, frequent reassortments, and possible recombinations. among these evolutionary events, reassortments refer to exchanges of discrete rna segments between co-infected influenza viruses, and they have ... | 2008 | 18942162 |
| [viferon suppositories in the treatment of influenza in adults]. | one hundred and one patients at the age of 18 to 60 years suffering from influenza were observed during increased ratio of the sickness due to the influenza virus types a (h1n1 and h3n2) and b. the diagnosis of influenza was confirmed by the laboratory tests. viferon was used in the treatment of 35 patients. the randomized double blind placebo-controlled study revealed high therapeutic efficacy ofviferon and its immunomodulating effect on the t-cells, the neutrophil phagocytic activity and the d ... | 2008 | 18942420 |
| comparisons of the influenza virus a m2 channel binding affinities, anti-influenza virus potencies and nmda antagonistic activities of 2-alkyl-2-aminoadamantanes and analogues. | the new 2-alkyl-2-aminoadamantanes and analogues 4-10 were designed and synthesized by simplification of the structure of the potent anti-influenza virus a spiranic aminoadamantane heterocycles 2 and 3. the aim of the present work was to examine the effects of bulky and extended lipophilic moieties attached to amantadine 1 on binding to the m2 channel and the resulting antiviral potency. the binding affinities of the compounds to the m2 protein of influenza virus a/chicken/germany/27 (weybridge ... | 2008 | 18947998 |
| [effect of anti-influenza virus h3n2 of hypericum japonicum in vivo]. | to investigate anti-influenza virus h3n2 effect of hypericum japonicum in vivo. | 2008 | 18973021 |
| adaptation of human influenza h3n2 virus in a mouse pneumonitis model: insights into viral virulence, tissue tropism and host pathogenesis. | most pandemic influenza virus strains undergo adaptation or reassortment before they acquire the ability to cause fatal infections in a new host species. the pathologic changes and tissue tropism during virus adaptation are not fully understood. here we investigated pathologic changes and tissue tropism by serial lung-to-lung passaging of human influenza virus strain a/aichi/2/68 (h3n2) in a balb/c mouse model. enhanced pulmonary lesions and systemic virus infection were observed during adaptati ... | 2009 | 18983930 |
| ongoing evolution of swine influenza viruses: a novel reassortant. | a novel h3n2 influenza virus strain isolated in germany from pigs with clinical symptoms of influenza is described. it was characterised by neutralisation test, hemagglutination inhibition test and complete sequencing of the genome. the data demonstrate the emergence of a h3n2 reassortant with the human-like hah3 gene of prevalent european porcine h3n2 influenza viruses and a nan2 gene of the european porcine h1n2 viruses. the gene segments of the internal proteins are avian-like, consistent wit ... | 2008 | 18985274 |
| anti-influenza virus activity of myrica rubra leaf ethanol extract evaluated using madino-darby canine kidney (mdck) cells. | myrica rubra leaf ethanol extract was added to culture medium of madino-darby canine kidney (mdck) cells inoculated with influenza virus, and the inhibition of influenza virus replication was measured. myrica rubra leaf ethanol extract showed anti-influenza virus activity irrespective of the hemagglutinin antigen type in the influenza virus type a (h1n1), its subtype (h3n2), and type b. | 2008 | 18997411 |
| the human h5n1 influenza a virus polymerase complex is active in vitro over a broad range of temperatures, in contrast to the wsn complex, and this property can be attributed to the pb2 subunit. | influenza a virus (iav) replicates in the upper respiratory tract of humans at 33 degrees c and in the intestinal tract of birds at close to 41 degrees c. the viral rna polymerase complex comprises three subunits (pa, pb1 and pb2) and plays an important role in host adaptation. we therefore developed an in vitro system to examine the temperature sensitivity of iav rna polymerase complexes from different origins. complexes were prepared from human lung epithelial cells (a549) using a novel adenov ... | 2008 | 19008377 |
| fusion of c3d with hemagglutinin enhances protective immunity against swine influenza virus. | h1n1 and h3n2 are the dominant subtypes causing swine influenza in china and other countries. it is important to develop effective vaccines against both h1n1 and h3n2 subtypes of swine influenza virus (siv). we examined the effects of a dna vaccine expressing an influenza ha fused to three copies of murine complement c3d in mice. plasmids encoding soluble ha (sha), complete ha (tmha), or a soluble fused form of ha (sha-mc3d3) were constructed from the h3n2 subtype of siv. the immune response was ... | 2009 | 19010505 |
| a novel neuraminidase deletion mutation conferring resistance to oseltamivir in clinical influenza a/h3n2 virus. | neuraminidase (na) mutations responsible for influenza resistance to oseltamivir vary according to the na subtype; in influenza a/h3n2 viruses, na-gene mutations occur predominantly at codons e119 and r292. in an oseltamivir-resistant influenza a/h3n2 virus isolated from an immunocompromised child after 107 days of cumulative treatment, the na gene contained 3 aa substitutions (n146k, s219t, and a272v) and a 4-aa deletion (del245-248); reversion mutation experiments using recombinant na proteins ... | 2009 | 19046066 |
| occurrence of swine influenza virus infection in swine with porcine respiratory disease complex. | we studied the occurrence of swine influenza virus (siv) infection in piglets with respiratory symptoms resembling porcine respiratory disease complex (prdc). a total of 106 samples including nasal swab and lung suspension from sick piglets were collected from 30 farms of medium size in the central and eastern parts of thailand from august 2006 to february 2007. samples were inoculated onto mardin-darby canine kidney (mdck) cells and siv infection was confirmed by immunofluorescent assay (ifa) a ... | 2008 | 19062693 |
| the host-dependent interaction of alpha-importins with influenza pb2 polymerase subunit is required for virus rna replication. | the influenza virus polymerase is formed by the pb1, pb2 and pa subunits and is required for virus transcription and replication in the nucleus of infected cells. as pb2 is a relevant host-range determinant we expressed a tap-tagged pb2 in human cells and isolated intracellular complexes. alpha-importin was identified as a pb2-associated factor by proteomic analyses. to study the relevance of this interaction for virus replication we mutated the pb2 nls and analysed the phenotype of mutant subun ... | 2008 | 19066626 |
| [the spread and biological properties of epidemic influenza viruses a and b strains circulating in the 2006-2007 season in russia]. | the epidemic upsurge of influenza morbidity in the 2006-2007 season in russia was caused by the active circulation of influenza a(h1n1), a(h3n2) and b viruses. the center for ecology and epidemiology of influenza studied 259 epidemic strains; all the strains were isolated on mdck cell cultures. influenza a(h1n1) viruses (n = 101) were antigenic variants of the references a/new caledonia/20/99 and a/solomon islands/3/06. influenza a(h3n2) viruses (n = 98) were antigenic variants of the references ... | 2008 | 19069788 |
| pathobiology of triple reassortant h3n2 influenza viruses in breeder turkeys and its potential implication for vaccine studies in turkeys. | triple reassortant (tr) h3n2 influenza viruses have been isolated from turkeys in the united states since 2003. these tr h3n2 virus infections have been associated with drastic declines in egg production in breeder turkeys although co-infection with multiple agents could have been responsible for exacerbating the clinical signs. in this study, we experimentally confirmed that tr h3n2 influenza virus alone can cause drastic reduction/complete cessation of egg production and pathology of the repro ... | 2009 | 19071183 |
| multiplex assay for simultaneously typing and subtyping influenza viruses by use of an electronic microarray. | we report on the use of an electronic microarray to simultaneously type influenza a and b viruses and to distinguish influenza a virus subtypes h1n1 and h3n2 from the potentially pandemic avian virus subtype h5n1. the assay targets seven genes: the h1, h3, h5, n1, and n2 genes of influenza a virus; the matrix protein m1 gene of influenza a virus; and the nonstructural protein (ns) gene of influenza b virus. by combining a two-step reverse transcription-multiplex pcr with typing and subtyping on ... | 2009 | 19073867 |
| anionic polymer, poly(methyl vinyl ether-maleic anhydride)-coated beads-based capture of human influenza a and b virus. | an anionic magnetic beads-based method was developed for the capture of human influenza a and b viruses from nasal aspirates, allantoic fluid and culture medium. a polymer, poly(methyl vinyl ether-maleic anhydride) [poly(mve-ma)], was used to endow magnetic beads with a negative charge and bioadhesive properties. after incubation with samples containing human influenza virus, the beads were separated from supernatants by applying a magnetic field. the adsorption [corrected] of the virus by the b ... | 2009 | 19081256 |
| genetic correlation between h3n2 human and swine influenza viruses. | h3n2 is one of the main subtypes of influenza virus which circulates in human and swine population throughout the world. | 2009 | 19083267 |
| in vivo and in vitro alterations in influenza a/h3n2 virus m2 and hemagglutinin genes: effect of passage in mdck-siat1 cells and conventional mdck cells. | no mutations were detected in the hemagglutinin gene of influenza a/h3n2 virus isolates from patients undergoing short-term amantadine treatment. however, genetic changes occurred after serial passage in either mdck or mdck-siat1 cells. our results showed that only a few mutations were observed in mdck-siat1-passaged isolates in the presence of amantadine. | 2009 | 19091815 |
| human influenza a viruses isolated in south america: genetic relations, adamantane resistance and vaccine strain match. | in order to gain insight into the genetic relations among h3n2 influenza a virus (iav) circulating in the south american region from 1999 to 2007, to investigate the presence of adamantane-resistant strains in this region, and to establish the genetic relations among that strains and vaccine strains recommended for the southern hemisphere, 11 haemagglutinin (ha) h3 iav sequences obtained from uruguayan patients were aligned with corresponding sequences from 68 h3 iav strains isolated in south am ... | 2009 | 19095085 |
| [analysis of influenza surveillance from 2000 to 2007 in gansu province]. | to study the epidemical characteristics of influenza in gansu province from 2000 to 2007, and to discuss the changes of the predominant strains of influenza virus. this study provide scientific basis for defending influenza effectively. | 2008 | 19105339 |
| reversion of influenza a (h3n2) virus from amantadine resistant to amantadine sensitive by further reassortment in japan during the 2006-to-2007 influenza season. | in the 2006-to-2007 influenza season, amantadine-sensitive strains were found among the n-lineage influenza a (h3n2) viruses, which were previously believed to be associated with amantadine resistance. whole-genome sequencing results indicated that this was due to a further reassortment event. | 2009 | 19109467 |
| influenza-associated morbidity in subtropical taiwan. | the purpose of this study was to assess the characteristics of influenza-associated morbidity in subtropical taiwan, corresponding to the seasonal patterns, weather, and co-circulation of influenza (sub)types, and other respiratory viruses, where the burden of influenza is poorly quantified. | 2009 | 19111494 |
| bronchointerstitial pneumonia in guinea pigs following inoculation with h5n1 high pathogenicity avian influenza virus. | the h5n1 high-pathogenicity avian influenza (hpai) viruses have caused widespread disease of poultry in asia, africa and the middle east, and sporadic human infections. the guinea pig model has been used to study human h3n2 and h1n1 influenza viruses, but knowledge is lacking on h5n1 hpai virus infections. guinea pigs were inoculated intranasally or intragastrically with a/vietnam/1203/04 (vn/04) or a/muscovy duck/vietnam/209/05 (mdk/vn/05) viruses. mild listlessness was seen at 2 and 3 days pos ... | 2009 | 19112127 |
| experimental infection of dogs with avian-origin canine influenza a virus (h3n2). | susceptible dogs were brought into contact with dogs experimentally infected with an avian-origin influenza a virus (h3n2) that had been isolated from a pet dog with severe respiratory syndrome. all the experimentally infected and contact-exposed dogs showed elevated rectal temperatures, virus shedding, seroconversion, and severe necrotizing tracheobronchitis and bronchioalveolitis. | 2009 | 19116051 |
| characterization of a canadian mink h3n2 influenza a virus isolate genetically related to triple reassortant swine influenza virus. | in 2007, an h3n2 influenza a virus was isolated from canadian mink. this virus was found to be phylogenetically related to a triple reassortant influenza virus which emerged in canadian swine in 2005, but it is antigenically distinct. the transmission of the virus from swine to mink seems to have occurred following the feeding of animals with a ration composed of uncooked meat by-products of swine obtained from slaughterhouse facilities. serological analyses suggest that the mink influenza virus ... | 2009 | 19116358 |
| transmission of influenza virus in a mammalian host is increased by pb2 amino acids 627k or 627e/701n. | since 2003, more than 380 cases of h5n1 influenza virus infection of humans have been reported. although the resultant disease in these cases was often severe or fatal, transmission of avian influenza viruses between humans is rare. the precise nature of the barrier blocking human-to-human spread is unknown. it is clear, however, that efficient human-to-human transmission of an antigenically novel influenza virus would result in a pandemic. influenza viruses with changes at amino acids 627 or 70 ... | 2009 | 19119420 |
| neuraminidase inhibitor resistance after oseltamivir treatment of acute influenza a and b in children. | oseltamivir, a specific influenza neuraminidase inhibitor, is an effective treatment for seasonal influenza. emergence of drug-resistant influenza viruses after treatment has been reported, particularly in children in japan, where the dosing schedule is different from that used throughout the rest of the world. we investigated the emergence of drug-resistant infection in children treated with a tiered weight-based dosing regimen. | 2009 | 19133796 |
| performance of a commercial swine influenza virus h1n1 and h3n2 antibody enzyme-linked immunosorbent assay in pigs experimentally infected with european influenza viruses. | the idexx swine influenza virus h1n1 and h3n2 enzyme-linked immunosorbent assays (elisas) are used worldwide, but their capacity to detect antibodies to european swine influenza viruses (sivs) has not been documented. a total of 313 well-defined sera from siv seronegative pigs and pigs experimentally infected with european sivs were used to compare the performance of both elisas and the hemagglutination inhibition (hi) test. the elisas largely failed to detect pigs that had been infected with h1 ... | 2009 | 19139506 |
| [in vitro study of antiviral activity of myramistin against subtypes h3n2 and h5n1 of influenza virus]. | in vitro antiviral effect of myramistin on influenza virus (mdck cell culture) was studied. the drug showed significant dose-dependent antiviral activity against the virus. when used prophylactically (1 hour before exposure to the virus) in subtoxic doses, myramistin was effective in inhibiting replication of the influenza virus [strains a/aichi/2/68 (h3n2) and a/chicken/suzdalka/nov-11/2005 (h5n1)]. in urgent prophylaxis (1 hour after exposure to the virus) the protective effect was less pronou ... | 2005 | 19140480 |
| histopathology and growth kinetics of influenza viruses (h1n1 and h3n2) in the upper and lower airways of guinea pigs. | recent investigations have shown that guinea pigs are important for the study of influenza a virus (iav) transmission. however, very little is known about iav replication and histopathology in the guinea pig respiratory tract. here, we describe viral growth kinetics, target cells and histopathology in the nasosinus, trachea and lungs of iav-infected guinea pigs. we found that guinea pigs infected with either a/puerto rico/8/34 (h1n1) or a/hong kong/8/68 (h3n2) developed a predominantly upper air ... | 2009 | 19141447 |
| in vitro anti-influenza viral activities of constituents from caesalpinia sappan. | six constituents with neuraminidase (na) inhibitory activity, namely brazilein, brazilin, protosappanin a, 3-deoxysappanchalcone, sappanchalcone and rhamnetin, were isolated from the hearthwood of caesalpinia sappan (leguminosae). their in vitro anti-influenza virus activities were evaluated with the cytopathic effect (cpe) reduction method. the results showed that 3-deoxysappanchalcone and sappanchalcone exhibited the highest activity against influenza virus (h3n2) with ic50 values of 1.06 and ... | 2009 | 19148862 |
| timely production of a/fujian-like influenza vaccine matching the 2003-2004 epidemic strain may have been possible using madin-darby canine kidney cells. | timely production and antigenic match with those of the epidemic strains are required for influenza vaccines. a/fujian/411/2002-like (h3n2) virus was the main epidemic influenza virus during the 2003/2004 season in the northern hemisphere. but a/fujian-like reassortant viruses were not available until more than one year later. we evaluated the a/kumamoto/102/2002 strain, an a/fujian/411/2002-like strain isolated in 2002, as a potential vaccine. we compared a/kumamoto/102/2002 viruses isolated fr ... | 2008 | 19149013 |
| co-administration of l-cystine and l-theanine enhances efficacy of influenza vaccination in elderly persons: nutritional status-dependent immunogenicity. | the immune response to influenza vaccine is attenuated in elderly persons, though they are at greatest risk for morbidity and mortality by influenza virus infection. experimental studies demonstrate that co-administration of l-cystine and l-theanine enhanced antigen-specific production of immunoglobulin in aged mice infected with influenza virus. we thus investigated the effect of l-cystine and l-theanine on antibody induction by influenza vaccines in elderly persons. | 2008 | 19149835 |
| blocking interhost transmission of influenza virus by vaccination in the guinea pig model. | interventions aimed at preventing viral spread have the potential to effectively control influenza virus in all age groups, thereby reducing the burden of influenza illness. for this reason, we have examined the efficacy of vaccination in blocking the transmission of influenza viruses between guinea pigs. three modes of immunization were compared: (i) natural infection; (ii) intramuscular administration of whole, inactivated influenza virus in 2 doses; and (iii) intranasal inoculation with live ... | 2009 | 19153237 |
| molecular evolution of human influenza a viruses in a local area during eight influenza epidemics from 2000 to 2007. | a total of 1,041 human influenza a virus isolates were collected at a clinic in niigata, japan, during eight influenza seasons from 2000 to 2007. the h3n2 subtype accounted for 75.4% of the isolates, and the rest were h1n1. extremely high rates of amantadine-resistant strains of h3n2 subtype were observed in 2005/2006 (100%) and 2006/2007 (79.4%), while amantadine-resistant strains of h1n1 subtype were only detected in 2006/2007 (48.2%). sequence and phylogenetic analysis of the ha1 subunit of t ... | 2009 | 19153639 |
| emergence of oseltamivir-resistant influenza a/h3n2 virus with altered hemagglutination pattern in a hematopoietic stem cell transplant recipient. | persistent influenza virus replication during antiviral therapy in patients undergoing hematopoietic stem cell transplantation (hsct) could promote the emergence of antiviral drug resistance. | 2009 | 19157971 |
| epidemiologic study of influenza infection in okinawa, japan, from 2001 to 2007: changing patterns of seasonality and prevalence of amantadine-resistant influenza a virus. | to clarify seasonal influenza patterns and the prevalence of amantadine-resistant influenza a viruses in okinawa, located at the southern extremity of japan in a subtropical climate, we conducted a laboratory-based study of influenza virus infections from 2001 to 2007. the annual outbreaks tended to show two peaks in okinawa, in summer and winter, although the main islands of japan, located in a temperate climate area, showed only winter influenza activity. epidemic types and subtypes in okinawa ... | 2009 | 19158265 |
| molecular evolution of ha1 in influenza a (h3n2) viruses isolated in japan from 1989 to 2006. | to evaluate the trend of phylogenetic evolution among influenza a (h3n2) viruses isolated in gunma and a (h3n2) vaccine strains, we studied the transition of gene mutations and amino acid substitution of the sites a and b in ha1 during long-term seasons. | 2009 | 19158442 |
| [distribution of avian influenza virus subtypes among domestic ducks in eastern china]. | to identify the distribution of avian influenza virus subtypes among domestic ducks in eastern china. | 2008 | 19160806 |
| start of the influenza season 2008-9 in europe - increasing influenza activity moving from west to east dominated by a(h3n2). | the influenza season 2008-9 started in week 49 of 2008 and is so far characterised by influenza virus type a subtype h3n2. isolates of this subtype that were tested proved susceptible to neuraminidase inhibitors, but resistant to m2 inhibitors. the circulating a(h3n2) viruses are antigenically similar to the component in the current northern hemisphere influenza vaccine. | 2009 | 19161722 |
| population dynamics of swine influenza virus in farrow-to-finish and specialised finishing herds in the netherlands. | influenza virus infections with subtypes h1n1, h3n2 and h1n2 are very common in domestic pigs in europe. data on possible differences of population dynamics in finishing pigs in farrow-to-finish herds and in specialised finishing herds are, however, scarce. the presence of sows and weaned piglets on the same premises may, however, affect the exposure of finishing pigs to influenza viruses. in a longitudinal study on 14 farrow-to-finish herds and 15 finishing herds, groups of pigs were followed b ... | 2009 | 19181461 |
| near-patient assays for diagnosis of influenza virus infection in adult patients. | rapid and reliable diagnosis of influenza is essential for identification of contagious patients and effective patient management. near-patient assays allow establishment of the diagnosis within minutes in young children, and this study aimed to evaluate near-patient assays in relation to the patient's age. a total of 194 patients with laboratory-confirmed influenza a/h3n2 virus infection, diagnosed within a prospective cohort study, were included. cryopreserved nasopharyngeal swabs collected fr ... | 2009 | 19183404 |
| multiorgan distribution of human influenza a virus strains observed in a mouse model. | multiorgan spread and pathogenesis of influenza infection with three human influenza a viruses was studied in mice. mouse-adapted viruses a/dunedin/4/73(h3n2), a/mississippi/1/85(h3n2), and a/pr/8/34(h1n1) differed considerably in virulence (p.f.u./ld(50)): 79,000 p.f.u. for dunedin, 5,000 p.f.u. for mississippi, and 65 p.f.u. for pr/8, which qualified dunedin as low virulent, mississippi as intermediate, and pr/8 as highly virulent. all three viruses were detected in lungs, heart, and thymus by ... | 2009 | 19189197 |
| sialic acid recognition is a key determinant of influenza a virus tropism in murine trachea epithelial cell cultures. | influenza a virus interacts with specific types of sialic acid during attachment and entry into susceptible cells. the precise amino acids in the hemagglutinin protein that control sialic acid binding specificity and affinity vary among antigenic subtypes. for h3 subtypes, amino acids 226 and 228 are critical for differentiating between alpha2,3- and alpha2,6-linked forms of sialic acid (sa). we demonstrate that position 190 of the ha from a/udorn/307/72 (h3n2) plays an important role in the rec ... | 2009 | 19195676 |
| anti-influenza virus activity and structure-activity relationship of aglycoristocetin derivatives with cyclobutenedione carrying hydrophobic chains. | previous studies have demonstrated that glycopeptide compounds carrying hydrophobic substituents can have favorable pharmacological (i.e. antibacterial and antiviral) properties. we here report on the in vitro anti-influenza virus activity of aglycoristocetin derivatives containing hydrophobic side chain-substituted cyclobutenedione. the lead compound 8e displayed an antivirally effective concentration of 0.4 microm, which was consistent amongst influenza a/h1n1, a/h3n2 and b viruses, and a sele ... | 2009 | 19200809 |
| activation of toll-like receptor signaling pathway for protection against influenza virus infection. | this study aims to evaluate the antiviral role of nucleic acid-based agonists for the activation of toll-like receptor (tlr) signaling pathways, and its protective role in respiratory influenza a virus infections. tlr-3 is expressed on myeloid dendritic cells, respiratory epithelium, and macrophages, and appears to play a central role in mediating both the antiviral and inflammatory responses of the innate immunity in combating viral infections. influenza viruses can effectively inhibit the host ... | 2009 | 19200852 |
| co-evolution positions and rules for antigenic variants of human influenza a/h3n2 viruses. | in pandemic and epidemic forms, avian and human influenza viruses often cause significant damage to human society and economics. gradually accumulated mutations on hemagglutinin (ha) cause immunologically distinct circulating strains, which lead to the antigenic drift (named as antigenic variants). the "antigenic variants" often requires a new vaccine to be formulated before each annual epidemic. mapping the genetic evolution to the antigenic drift of influenza viruses is an emergent issue to pu ... | 2009 | 19208143 |
| comparison of the performance of the rapid antigen detection actim influenza a&b test and rt-pcr in different respiratory specimens. | nowadays, influenza antigen detection test kits are used most frequently to detect influenza a or b virus to establish the diagnosis of influenza rapidly and initiate appropriate therapy. this study was conducted to evaluate the performance of the actim influenza a&b test (medix biochemica). overall, 473 respiratory specimens were analysed in the actim influenza a&b test and the results were compared with those from an rt-pcr assay; 461 of these samples originated from paediatric patients aged 7 ... | 2009 | 19208888 |
| emerging influenza virus: a global threat. | since 1918, in?uenza virus has been one of the major causes of morbidity and mortality, especially among young children. though the commonly circulating strain of the virus is not virulent enough to cause mortality, the ability of the virus genome to mutate at a very high rate may lead to the emergence of a highly virulent strain that may become the cause of the next pandemic. apart from the influenza virus strain circulating in humans (h1n1 and h3n2), the avian influenza h5n1 h7 and h9 virus st ... | 2008 | 19208973 |
| h5n1 vaccine-specific b cell responses in ferrets primed with live attenuated seasonal influenza vaccines. | live attenuated influenza h5n1 vaccines have been produced and evaluated in mice and ferrets that were never exposed to influenza a virus infection (suguitan et al., plos medicine, e360:1541, 2006). however, the preexisting influenza heterosubtypic immunity on live attenuated h5n1 vaccine induced immune response has not been evaluated. | 2009 | 19209231 |
| combining mutual information with structural analysis to screen for functionally important residues in influenza hemagglutinin. | influenza hemagglutinin mediates both cell-surface binding and cell entry by the virus. mutations to hemagglutinin are thus critical in determining host species specificity and viral infectivity. previous approaches have primarily considered point mutations and sequence conservation; here we develop a complementary approach using mutual information to examine concerted mutations. for hemagglutinin, several overlapping selective pressures can cause such concerted mutations, including the host imm ... | 2009 | 19209725 |
| deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent h3n2 influenza viruses. | influenza viruses attach to cells via sialic acid receptors. the viral neuraminidase (na) is needed to remove sialic acids so that newly budded virions can disperse. known mechanisms of resistance to na inhibitors include mutations in the inhibitor binding site, or mutations in the hemagglutinin that reduce avidity for sialic acid and therefore reduce the requirement for na activity. | 2009 | 19216793 |
| [therapeutic efficacy of ingavirin, a new domestic formulation against influenza a virus (h3n2)]. | investigation of the therapeutic efficacy of ingavirin (valenta farmacevtica, russia) against influenza virus a (h3n2) vs. tamiflu, remantadin and arbidol showed that in daily doses of 15 and 20 mg/kg (equal by the efficacy to the human doses of 90 and 120 mg) ingavirin was effective in protection of the albino mice infected by the virus in a dose of 10 to 15 ld50. the protective efficacy was 38.3-39.2% and the increase of the average lifespan amounted to 4.2-4.4 days. the ingavirin efficacy was ... | 2008 | 19227120 |