Occurrence of human respiratory syncytial virus in summer in Japan.

In temperate zones, human respiratory syncytial virus (HRSV) outbreaks typically occur in cold weather, i.e. in late autumn and winter. However, recent outbreaks in Japan have tended to start during summer and autumn. This study examined associations of meteorological conditions with the numbers of HRSV cases reported in summer in Japan. Using data from the HRSV national surveillance system and national meteorological data for summer during the period 2007-2014, we utilized negative binomial logistic regression analysis to identify associations between meteorological conditions and reported cases of HRSV. HRSV cases increased when summer temperatures rose and when relative humidity increased. Consideration of the interaction term temperature × relative humidity enabled us to show synergistic effects of high temperature with HRSV occurrence. In particular, HRSV cases synergistically increased when relative humidity increased while the temperature was ⩾28·2 °C. Seasonal-trend decomposition analysis using the HRSV national surveillance data divided by 11 climate divisions showed that summer HRSV cases occurred in South Japan (Okinawa Island), Kyushu, and Nankai climate divisions, which are located in southwest Japan. Higher temperature and higher relative humidity were necessary conditions for HRSV occurrence in summer in Japan. Paediatricians in temperate zones should be mindful of possible HRSV cases in summer, when suitable conditions are present.

Single, double, and triple Auger decays from 1s shake-up states of the oxygen molecule.

The single, double, and triple Auger decays from the 1s shake-up states of O2 have been studied using a multi-electron coincidence method. Efficient populations of two-hole final states are observed in single Auger decays of the π-π* shake-up states, which is understood as a characteristic property of the Auger transitions from shake-up states of an open-shell molecule. The O23+ populations formed by double Auger decays show similar profiles for both the O1s-1 and shake-up states, which is due to the contributions from cascade double Auger processes. While the cascade contributions to the double Auger decays increase with the initial shake-up energy, the probability of direct double Auger processes remains unchanged between the O1s-1 and shake-up states, which implies a weak influence of the excited electron on the double Auger emission that originates from the electron correlation effect.

Characterization of influenza outbreaks in Lebanon during the 2013/14 and 2014/15 seasons.

Despite the significant burden of influenza outbreaks, active disease monitoring has been largely absent in the Middle East, including Lebanon. In this study we characterized influenza virus in 440 nasopharyngeal swabs collected from patients with acute respiratory infections during two influenza seasons in Lebanon. Influenza A(H3N2) was dominant in the 2013/14 season while the A(H1N1)pdm09 and B/Yamagata strains were most prevalent in the 2014/15 season. All tested isolates were susceptible to 4 neuraminidase inhibitors (oseltamivir, zanamivir, peramivir and laninamivir). Genetic analysis of the haemagglutinin gene revealed multiple introductions of influenza viruses into Lebanon from different geographic sources during each season. Additionally, large data gaps were identified in the Middle East region, as indicated by the lack of current influenza sequences in the database from many countries in the region.

A community cluster of influenza A(H1N1)pdm09 virus exhibiting cross-resistance to oseltamivir and peramivir in Japan, November to December 2013.

Six influenza A(H1N1)pdm09 viruses were detected in Sapporo, Japan, between November and December 2013. All six viruses possessed an H275Y substitution in the neuraminidase protein, which confers cross-resistance to oseltamivir and peramivir. No epidemiological link among the six cases could be identified; none of them had received neuraminidase inhibitors before specimen collection. The haemagglutinin and neuraminidase genes of the six viruses were closely related to one another, suggesting clonal spread of a single resistant virus.

Communication: Formation of slow electrons in the Auger decay of core-ionized water molecules.

Double Auger decay of O1s(-1) and its satellite states in H(2)O has been studied with a multi-electron coincidence method, and a process leading to autoionizing O* fragments has been revealed. The breaking of the two O-H bonds producing the autoionizing O* fragments occurs for highly excited H(2)O(2+) populated by the initial Auger decay. The O* fragments are more favorably produced in the decay from the satellite states, resulting from the larger population of highly excited H(2)O(2+) states inheriting the valence excitation in the initial state.

Temperature-sensitive defect of influenza A/Ann Arbor/6/60 cold-adapted variant leads to a blockage of matrix polypeptide incorporation into the plasma membrane of the infected cells.

A temperature-sensitive (ts) defect in growth of the A/Ann Arbor/6/60 (A/AA/60) cold-adapted (ca) and ts variant strain has been studied. At the restrictive temperature of 38.5 degrees C, the variant synthesized all the viral polypeptides in normal amounts within the infected cells, but the virions released into the culture fluid contained greatly reduced amounts of the matrix (M1) polypeptide and showed significantly low infectivity per unit hemagglutinin activity. Cell fractionation experiments revealed that incorporation of the M1 polypeptide into plasma membranes of the variant-infected cells was selectively reduced at 38.5 degrees C, whilst it occurred normally at 34 degrees C. The ts reassortants between the A/AA/60 variant and the A/AA/1/80 wild type (wt) strain (non-ts), which had the M gene derived from the wt parent, also showed similar patterns. These results suggest that the ts defect of the variant and its ts reassortants involves the process of incorporation of the M1 polypeptide into the plasma membranes of the infected cells and that this defect is not attributable to the M gene of the variant.

The staphylokinase gene is located in the structural gene encoding N-acetylmuramyl-L-alanine amidase in methicillin-resistant Staphylococcus aureus.

The nucleotide sequence of a 15600-bp DNA fragment containing the staphylokinase gene (sakNU3-1) of methicillin-resistant Staphylococcus aureus (MRSA) NU3-1 was determined. The sak gene was found within the ply gene encoding N-acetylmuramyl-L-alanine amidase and thus the ply gene should be inactivated. In the flanking region of the sak gene, the tandem repeat sequences (GAAGTGTT and GAATGGTT) were present as possible junction points between the sak and ply genes. No sequences characteristic of the presence of an IS-like element were found. Upstream from the ply gene, the kdpA, kdpB and kdpC homologues were present. Downstream from the ply gene, the tagA, tagH and tagG homologues were present. The sak gene was inserted into the same position of ply in 5/6 of sak(+) MRSA isolates with different genotypes. In all of these sak(+) isolates, Sak was detected in the culture supernatant.

Positive reactions to common allergens in 42 atopic dogs in Japan.

Clinically important allergens for the diagnosis and treatment of atopic dermatitis vary geographically. In order to identify the most prevalent allergens in atopic dogs in Japan, 42 dogs with a clinical diagnosis of atopy were tested using both in vivo (intradermal skin test (IDST)) and in vitro (antigen-specific IgE assay) allergy tests. Allergens used for IDST included 26 allergen extracts from eight allergen groups: trees, weeds, grasses, house dust mites (HDM), molds, foods, epithelia, and arthropods. Immunodot assay was used to measure antigen-specific IgE against 24 allergens from these eight groups and against fish such as cod and sole. In the 42 dogs, the most common positive allergen reaction was to HDM on both IDST (29/42 dogs or 69%) and in vitro testing (23/42 or 54.8%). The second most frequent positive allergen reaction was to Japanese cedar pollen (21/42 or 50.0% for IDST and 7/42 or 16.7% for in vitro testing). In both tests, less than 20% of dogs had positive reactions to molds or foods. Positive reactions to cat epithelia were frequently found on IDST, but rarely found on in vitro testing. Agreement between the two tests was found in 26 instances: HDM (21 dogs), Japanese cedar pollen (five dogs) and wheat (one dog). In this study, the two most common allergens involved in atopic dermatitis in dogs in Japan were HDM and Japanese cedar pollen.

Experimental sensitization with Japanese cedar pollen in dogs.

Japanese cedar pollinosis is a type I allergic disease mediated by immunoglobulin E (IgE) antibodies to Japanese cedar (Cryptomeria japonica) pollen antigen (CPAg). By using 22 dogs consisting of 20 dogs aged 3 months and 2 dogs aged 3 years, immunization was performed by subcutaneous injections of CPAg with aluminum hydroxide gel. Variable levels of CPAg-specific IgE antibody response were detected in 21 of the 22 immunized dogs two weeks after the second immunization. This study provided an experimental sensitization system with CPAg in dogs, which will be useful for further immunological studies on Japanese cedar pollinosis.

Serological evidence of H1 influenza virus infection among Japanese hogs.

Classical H1 influenza firus infection among Japanese hogs was confirmed in 1978 by serological examination. Of 820 swine sera collected from July 1977 to February 1979 in Miyagi Prefecture, northern Japan, six sera were found to contain haemagglutination inhibition (HI) antibodies to the A/FM/1/47 (H1N1) strain. Of the six sera, one showed a significant high HI antibody titre, which was classified as IgM, to the FM1 strain, but not the other H1N1 variants. These results strongly suggest that hogs may carry an old type of H1 influenza virus. The possible role of pigs as a reservoir of human pandemic influenza strains is discussed.

Annual examination of influenza virus infection among pigs in Miyagi prefecture, Japan: the appearance of Hsw1N1 virus.

Annual dissemination of swine and Hong Kong influenza viruses among hogs in Miyagi prefecture, Japan, was examined by virus recovery and serological tests. The serological examination revealed that two distinct influenza A viruses, H3N2 and Hsw1N1, had caused dual epidemic in pigs since mid-1977. Some individual sera contained antibodies against both strains. Although positive sera against Hong Kong or swine influenza viruses appeared in the serosurvey throughout the year, the positive ratios indicated a peak in the early spring of 1978. During this high prevalence period, positive sera against the H3N2 strain were found throughout the prefecture, but high incidences of Hsw1N1 virus were found only in limited areas to the north-east of Sendai City. Four strains of influenza A virus were isolated from bronchial swabs collected from hogs in April, 1978. These strains were identified as Hsw1N1 viruses and were closely related to the A/New Jersey/8/76 strain.

Isolation and characterization of influenza A viruses from wild ducks in northern Japan: appearance of HSW1 antigens in the Japanese duck population.

Twenty-six influenza A viruses were isolated from cloacal and tracheal samples of 235 resident and 396 migratory ducks in Miyagi prefecture, Japan, in 1977--78. Of these, twelve were antigenically related to the avian-origin HSW1 virus, A/duck/Alberta/35/76 (HSW1N1), but their neuraminidase antigens were characterized as Nav2-3, Nav4 or N2. These antigenic configuration have not previously been reported. In addition, one strain in which the neuraminidase antigen was identified as Nav4, was demonstrated to be a mixture of two haemagglutinins, HSW1 and Hav7. Two distinct strains were separated from the mixture and characterized as HSW1Nav4 and Hav7Nav4. The antigenic identification of an additional 13 influenza A viruses revealed the presence of six haemagglutinin subtypes (Hav1, Hav3, Hav4, Hav6, Hav7, and Hav8) and five neuaraminidase subtypes (Nav1, Nav2-3, Nav4, Neq2, and N2) in various combinations. The results suggest that the avian influenza A viruses among feral ducks may be isolated in various combinations of haemagglutinins and neuraminidase subtypes in Japan, and that feral ducks may be the site of genetic recombination occurring as a result of dual infection with different subtypes of influenza A virus.

[Study of development of autoantibody to beta-adrenergic receptors in asthmatics].

An (125I) iodohydroxybenzyl pindolol (125IHYP) binding inhibition assay was performed. Various dilutions (1:5-1:500) of sera from asthmatics and controls were incubated with canine lung membranes for 60 minutes at 30 degrees C. 125IHYP was added to the membranes for 30 minutes at room temperature in the presence and absence of 10 microM 1-propranolol, and the samples were washed through a Gelman (Type A-E) glass fiber filter using a washing buffer. Radio activity was measured with Aloka gamma counter. In the presence of various serum dilutions from asthmatics, 125IHYP specific bindings of 0.16 fmol to 4.38 fmol were measured. 125IHYP binding was inhibited in a dose-related and nonspecific manner. Serum, albumin, L-histidine and L-cysteine also inhibited 125IHYP specific binding to beta-receptors. Percentages of inhibition of serum from asthmatics on 125IHYP specific finding to beta-receptors were -17.6% to +9.3%, which were compared with identical dilutions of control serum. There was no significant difference in 125IHYP binding inhibition assay between asthmatics and controls. From these results, development of autoantibody to beta-adrenergic receptors could not be detected in this study.

[Functions of the segment-specific noncoding regions of influenza virus genome RNA].

The genome of influenza A viruses consists of eight negative-strand RNA segments. These segments contain the untranslated regions (UTRs), ranging from 20 to 61 nucleotides, at their 3' and 5' ends. The UTRs are composed of the highly conserved terminal nucleotides and the segment-specific nonconserved nucleotides located adjacent the open reading frame of the viral RNAs. Utilizing the virus-like model RNAs, whose nonconserved UTRs were mutated, deleted or replaced with those of other segments, the unique features of the nonconserved UTRs have been elucidated in the steps of transcription, translation, replication and RNA packaging into virus particles. Here I summarize current understanding of the functions of the segment-specific nonconserved UTRs of virus RNA.

Influenza gain-of-function experiments: their role in vaccine virus recommendation and pandemic preparedness.

In recent years, controversy has arisen regarding the risks and benefits of certain types of gain-of-function (GOF) studies involving avian influenza viruses. In this article, we provide specific examples of how different types of data, including information garnered from GOF studies, have helped to shape the influenza vaccine production process-from selection of candidate vaccine viruses (CVVs) to the manufacture and stockpiling of safe, high-yield prepandemic vaccines for the global community. The article is not written to support a specific pro- or anti-GOF stance but rather to inform the scientific community about factors involved in vaccine virus selection and the preparation of prepandemic influenza vaccines and the impact that some GOF information has had on this process.

Mechanism of NKT cell activation by intranasal coadministration of alpha-galactosylceramide, which can induce cross-protection against influenza viruses.

In a nasal vaccine against influenza, the activation of natural killer T (NKT) cells by intranasal coadministration of alpha-galactosylceramide (alpha-GalCer) can potently enhance protective immune responses. The results of this study show that the NKT cell-activated nasal vaccine can induce an effective cross-protection against different strains of influenza virus, including H5 type. To analyze the mechanism of NKT cell activation by this nasal vaccine, we prepared fluorescence-labeled alpha-GalCer by which we detect a direct interaction between NKT cells and alpha-GalCer-stored dendritic cells in nasal mucosa-associated tissues. Accordingly, although very few NKT cells exist at mucosa, the nasal vaccination induced a localized increase in NKT cell population, which is partly dependent on CXCL16/CXCR6. Furthermore, we found that NKT cell activation stimulates mucosal IgA production by a mechanism that is dependent on interleukin (IL)-4 production. These results strengthen the basis of nasal vaccination via NKT cell activation, which can induce immune cross-protection.

Reverse misreading of a GC doublet by the modified T7 DNA polymerase, Sequenase.

In nucleotide sequencing of the cDNA of the influenza virus PB2 polymerase gene by the dideoxy method using a modified T7 DNA polymerase, Sequenase, the sequence of the promoter region, 5'-AGCGAAAGCAGG, was shown to be misread as 5'-AGCGAAACGAGG, i.e., a GC doublet at positions 8 and 9 was read in reverse. This misreading was also found both when the sequence of BsmI restriction site upstream from the PB2 promoter sequence was exchanged by that of the promoter of T7 RNA polymerase and when the downstream region was substituted with the nonstructural (NS) protein gene. These results indicated that the misreading by Sequenase was attributed specifically to the PB2 promoter region, independent of the upstream and downstream sequences. The misreading, however, did not occur when dGTP in the labeling mixture was substituted with another nucleotide analog, dITP. Furthermore, the reversion did not occur in the NS gene promoter region, where the nucleotide sequence was 5'-AGCAAAAGCAGG. Since the nucleotide difference between the PB2 and NS promoter regions was only at the fourth residue, i.e., G for PB2 and A for PB2 and A for NS, the G residue followed by a triplet AAA in the PB2 promoter region was suggested to be a signal responsible for the misreading by Sequenase T7 DNA polymerase. The findings warns of possible misreading in determining DNA sequences, in addition to compression of the sequencing ladder.