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Lee VJ Tan CH Yap J Cook AR Ting PJ Loh JP Gao Q Chen MI Kang WL Tan BH Tambyah PA 《PloS one》2011,6(10):e26572
Background
Limited information is available about pandemic H1N1-2009 influenza vaccine effectiveness in tropical communities. We studied the effectiveness of a pandemic H1N1 vaccination program in reducing influenza cases in Singapore.Methods
A surveillance study was conducted among military personnel presenting with febrile respiratory illness from mid-2009 to mid-2010. Consenting individuals underwent nasal washes, which were tested with RT-PCR and subtyped. A vaccination program (inactivated monovalent Panvax H1N1-2009 vaccine) was carried out among recruits. A Bayesian hierarchical model was used to quantify relative risks in the pre- and post-vaccination periods. An autoregressive generalised linear model (GLM) was developed to minimise confounding.Results
Of 2858 participants, 437(15.3%), 60(2.1%), and 273(9.6%) had pandemic H1N1, H3N2, and influenza B. The ratio of relative risks for pandemic H1N1 infection before and after vaccination for the recruit camp relative to other camps was 0.14(0.016,0.49); for H3N2, 0.44(0.035,1.8); and for influenza B, 18(0.77,89). Using the GLM for the recruit camp, post-vaccination weekly cases decreased by 54%(37%,67%, p<0.001) from that expected without vaccination; influenza B increased by 66 times(9–479 times, p<0.001); with no statistical difference for H3N2 (p = 0.54).Conclusions
Pandemic vaccination reduced H1N1-2009 disease burden among military recruits. Routine seasonal influenza vaccination should be considered. 相似文献4.
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Yuan Jin Dong Yu Hongguang Ren Zhiqiu Yin Zhisong Huang Mingda Hu Beiping Li Wei Zhou Junjie Yue Long Liang 《BMC genomics》2014,15(1)
Background
During the past two decades, avian influenza A H9N2 viruses have spread geographically and ecologically in China. Other than its current role in causing outbreaks in poultry and sporadic human infections by direct transmission, H9N2 virus could also serve as an progenitor for novel human avian influenza viruses including H5N1, H7N9 and H10N8. Hence, H9N2 virus is becoming a notable threat to public health. However, despite multiple lineages and genotypes that were detected by previous studies, the migration dynamics of the H9N2 virus in China is unclear. Increasing such knowledge would help us better prevent and control H9N2 as well as other future potentially threatening viruses from spreading across China. The objectives of this study were to determine the source, migration patterns, and the demography history of avian influenza A H9N2 virus that circulated in China.Results
Using Bayesian phylogeography framework, we showed that the H9N2 virus in mainland China may have originated from the Hong Kong Special Administrative Region (SAR). Southern China, most likely the Guangdong province acts as the primary epicentre for multiple H9N2 strains spreading across the whole country, and eastern China, most likely the Jiangsu province, acts as an important secondary source to seed outbreaks. Our demography inference suggests that during the long-term migration process, H9N2 evolved into multiple diverse lineages and then experienced a selective sweep, which reduced its genetic diversity. Importantly, such a selective sweep may pose a greater threat to public health because novel strains confer higher fitness advantages than strains being replaced and could generate new viruses through reassortment.Conclusion
Our analyses indicate that migratory birds, poultry trade and transportation have all contributed to the spreading of the H9N2 virus in China. The ongoing migration and evolution of H9N2, which poses a constant threat to the human population, highlights the need for a more comprehensive surveillance of wild birds and for the enhancement of biosafety for China’s poultry industry.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-1110) contains supplementary material, which is available to authorized users. 相似文献7.
Toshiyuki Katagi 《Plant Growth Regulation》1989,8(3):283-284
Book Review
Pesticide formulations: Innovations and developmentsB. Cross and H.B. Scher (Eds.), ACS Symposium Series 371. Washington DC: American Chemical Society, 1988. xi + 288 pages. £54.00. ISBN 0-8412-1483-2 相似文献8.
Book reviews
Molecular biology of photosynthesisGovindjee, H.J. Bohnert, W. Bottomley, D.A. Bryant, J.E. Mullet, W.L. Ogren, H. Pakrasi, and C.R. Somerville (Eds.), Dordrecht: Kluwer Academic Publishers, 1989. xxvii + 815 pages. £130.00. ISBN 0-7923-0097-1 相似文献9.
Background
Avian influenza virus (AIV) subtypes H5 and H7 attracts particular attention because of the risk of their potential pathogenicity in poultry. The haemagglutination inhibition (HI) test is widely used as subtype specific test for serological diagnostics despite the laborious nature of this method. However, enzyme-linked immunosorbent assays (ELISAs) are being explored as an alternative test method.H5 and H7 specific monoclonal antibodies were experimentally raised and used in the development of inhibition ELISAs for detection of serological response specifically directed against AIV subtypes H5 and H7. The ELISAs were evaluated with polyclonal chicken anti-AIV antibodies against AIV subtypes: H1N2, H5N2, H5N7, H7N1, H7N7, H9N9, H10N4 and H16N3.Results
Both the H5 and H7 ELISA proved to have a high sensitivity and specificity and the ELISAs detected H5 and H7 antibodies earlier during experimental infection than the HI test did. The reproducibility of the ELISA’s performed at different times was high with Pearson correlation coefficients of 0.96-0.98.Conclusions
The ELISAs are a potential alternative to the HI test for screening of large amounts of avian sera, although only experimental sera were tested in this study.10.
Anna Pugatshova ülle Kikas Margit Prüssel Aivo Reinart Eduard Tamm et al. 《Plant Growth Regulation》1991,10(2):177-178
Book Review
Principles of environmental physicsJ.L. Monteith and M.H. Unsworth Second edition. London: Edward Arnold, 1990. xii + 291 pages. £30.00 (hardback), £14.95 (paperback). ISBN 0-7131-2931-X 相似文献11.
Book Review
Progress in botanyH.-D. Behnke, K. Esser, K. Kubitzki, M. Runge and H. Ziegler (Eds.), 50. Berlin: Springer-Verlag, 1989. XIX+386 pages. DM 258.00. ISBN 3-540-50289-0 相似文献12.
Cowburn Richard F. Wiehager Birgitta Trief Ewa Li-Li Mo Sundström Erik 《Neurochemical research》1997,22(12):1437-1442
The neurotoxic fragment corresponding to residues 25-35 of the -amyloid (A) peptide [A-(25-35)] has been shown to exert effects on (+)-[3H]5-methyl-10,11-dihydro-5H-dibenzo[a,d]-cyclohepten-5,10-imine maleate ([3H]MK-801) binding to the cation channel of the N-methyl-D-aspartate (NMDA) receptor. In the present study, we investigated whether the amidated and carboxylic acid C-terminated forms of A-(25-35) [A-(25-35-NH2) and A-(25-35-COOH), respectively] exert effects on other excitatory amino acid receptor and cation channel types in rat cortical membranes. Both A-(25-35-NH2) and A-(25-35-COOH) gave statistically significant dose-dependent inhibitions of [3H]glutamate and [3H]glycine binding to the agonist recognition sites of the NMDA receptor. Ten M A-(25-35-NH2) and A-(25-35-COOH) gave 25% and 20% inhibitions of [3H]glutamate binding and 75% and 70% inhibitions of [3H]glycine binding, respectively. A-(25-35-NH2), but not A-(25-35-COOH), gave a small (ca. 17% at 10 M) statistically significant increase of [3H]amino-3-hydroxy-5-methylisoxazole-4-propionate ([3H]AMPA) binding. [3H]kainate binding was not significantly affected by either peptide. Similarly, neither peptide affected either the maximal level or EC50 value for calcium stimulation of [3H]nitrendipine binding. It is concluded that A-(25-35) shows slight affinity for the agonist recognition sites of the NMDA receptor, but not for other excitatory amino acid receptor types or for L-type voltage-dependent calcium channels. 相似文献
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Tian Hong Wu Jingyan Chen Yan Zhang Keshan Shang Youjun Liu Xiangtao 《Virology journal》2012,9(1):1-4
Background
Virus subtype H13N2, A/mallard/Kr/SH38-45/2010 (H13N2), was first isolated from a mallard fecal sample in South Korea.Results
Phylogenetic analysis of all eight viral genes revealed that this virus emerged by genetic mixing between Eurasian and North American gene pools, and possibly between wild ducks and gulls. The H13 and N2 surface genes clustered together in a group with Eurasian isolates from gulls and wild birds, respectively. The PB2, PA, NP, M and NS segments belonged to the Eurasian lineage, whereas the PB1 gene clustered in the North American lineage. Furthermore, they showed a bird-dependent pattern in phylogenetic analysis: the M gene was similar to subtype H13 viruses within gulls, whereas other segments were similar to avian influenza viruses of other subtypes from wild ducks.Conclusions
The data suggests that the novel reassortant H13N2 virus isolated in South Korea might have emerged by genetic reassortment between intercontinental and interspecies transmission in wild birds. 相似文献14.
Punyadarsaniya D Liang CH Winter C Petersen H Rautenschlein S Hennig-Pauka I Schwegmann-Wessels C Wu CY Wong CH Herrler G 《PloS one》2011,6(12):e28429
Background
Swine are important hosts for influenza A viruses playing a crucial role in the epidemiology and interspecies transmission of these viruses. Respiratory epithelial cells are the primary target cells for influenza viruses.Methodology/Principal Findings
To analyze the infection of porcine airway epithelial cells by influenza viruses, we established precision-cut lung slices as a culture system for differentiated respiratory epithelial cells. Both ciliated and mucus-producing cells were found to be susceptible to infection by swine influenza A virus (H3N2 subtype) with high titers of infectious virus released into the supernatant already one day after infection. By comparison, growth of two avian influenza viruses (subtypes H9N2 and H7N7) was delayed by about 24 h. The two avian viruses differed both in the spectrum of susceptible cells and in the efficiency of replication. As the H9N2 virus grew to titers that were only tenfold lower than that of a porcine H3N2 virus this avian virus is an interesting candidate for interspecies transmission. Lectin staining indicated the presence of both α-2,3- and α-2,6-linked sialic acids on airway epithelial cells. However, their distribution did not correlate with pattern of virus infection indicating that staining by plant lectins is not a reliable indicator for the presence of cellular receptors for influenza viruses.Conclusions/Significance
Differentiated respiratory epithelial cells significantly differ in their susceptibility to infection by avian influenza viruses. We expect that the newly described precision-cut lung slices from the swine lung are an interesting culture system to analyze the infection of differentiated respiratory epithelial cells by different pathogens (viral, bacterial and parasitic ones) of swine. 相似文献15.
Background
Heparan sulfate proteoglycans (HSPGs) modulate the binding and activation of signaling pathways of specific growth factors, such as fibroblast growth factor-2 (FGF-2). Human endosulfatase 1 (HSULF-1) is an enzyme that selectively removes 6-O sulfate groups from HS side chains and alter their level and pattern of sulfation and thus biological activity. It is known that HSULF-1 is expressed at low levels in some cancer cell lines and its enhanced expression can inhibit cancer cell growth or induce apoptosis, but the mechanism(s) involved has not been identified.Methods
HSULF-1 mRNA expression was assessed in five normal cells (primary human lung alveolar type 2 (hAT2) cells, adult lung fibroblasts (16Lu), fetal lung fibroblasts (HFL), human bronchial epithelial cells (HBE), and primary human lung fibroblasts (HLF)) and five lung cancer cell lines (A549, H292, H1975, H661, and H1703) using quantitative real time polymerase chain reaction (qRT-PCR). H292 and hAT2 cells over-expressing HSULF-1 were analyzed for cell viability, apoptosis, and ERK/Akt signaling, by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, TUNEL (Terminal deoxynucleotidyl transferase dUTP nick end labeling) assay, and Western Blot, respectively. Apoptosis pathway activation was confirmed by PCR array in hAT2, H292, and A549 cells.Results
HSULF-1 was expressed at a significantly lower level in epithelial cancer cell lines compared to normal cells. Infection with recombinant adenovirus for HSULF-1 over-expression resulted in decreased cell viability in H292 cells, but not in normal hAT2 cells. HSULF-1 over-expression induced apoptosis in H292 cells, but not in hAT2 cells. In addition, apoptosis pathways were activated in both H292 and A549 cells, but not in hAT2 cells. HSULF-1 over-expression reduced ERK and Akt signaling activation in H292 cells, which further demonstrated its inhibitory effects on signaling related to proliferation.Conclusions
These results indicate that HSULF-1 is expressed at lower levels in H292 lung cancer cells than in normal human alveolar cells and that its over-expression reduced cell viability in H292 cells by inducing apoptotic pathways, at least in part by inhibiting ERK/Akt signaling. We hypothesize that HSULF-1 plays important roles in cancer cells and functions to modify cell signaling, inhibit cancer proliferation, and promote cancer cell death. 相似文献16.
Veiko Krauss Anne Fassl Petra Fiebig Ina Patties Heinz Sass 《BMC evolutionary biology》2006,6(1):18-15
Background
In eukaryotes, histone H3 lysine 9 (H3K9) methylation is a common mechanism involved in gene silencing and the establishment of heterochromatin. The loci of the major heterochromatic H3K9 methyltransferase Su(var)3-9 and the functionally unrelated γ subunit of the translation initiation factor eIF2 are fused in Drosophila melanogaster. Here we examined the phylogenetic distribution of this unusual gene fusion and the molecular evolution of the H3K9 HMTase Su(var)3-9. 相似文献17.
Antonia Patruno Sara Franceschelli Mirko Pesce Cristina Maccallini Marialuigia Fantacuzzi Lorenza Speranza Alessio Ferrone Maria Anna De Lutiis Emanuela Ricciotti Rosa Amoroso Mario Felaco 《Biochimica et Biophysica Acta (BBA)/General Subjects》2012
Background
Previous reports suggest that NO may contribute to the pathophysiology of septic shock. Recently, we have synthesized and characterized a series of benzyl- and dibenzyl derivative of N-(3-aminobenzyl)acetamidine, a potent and selective inhibitor of iNOS, in vitro assay. We evaluated the molecular mechanisms by which these compounds are involved in the regulation of NOSs expression.Methods
H9c2 cells were stimulated with lipopolysaccharide (LPS) in the presence or absence of acetamidine-derivative. The NOSs mRNA and protein, and activation of signaling pathways (Akt and NF-κB) were assayed.Results
The induction of endotoxic shock in H9c2 with LPS caused an increase of inducible NOS and a down-regulation of constitutive NOS. The molecular mechanism involved in the modulation of NOSs expression in H9c2 cells upon LPS stimulation resulted in the modification of the redox state responsible for NF-kB nuclear translocation via NIK -IKKα/β-IkBα, simultaneously to the inactivation of the PI3K/Akt pathway. The compounds acted as an anti-inflammatory modulator.Conclusion
These results suggest that LPS regulates the opposite NOS expression in H9c2 cells by modifying the redox state of these cells responsible for the NF-kB nuclear translocation via NIK–IKKα/β‐IkBα, simultaneous to the inactivation of the PI3K/Akt pathway. The new molecule acts as an anti-inflammatory modulator in LPS-induced inflammation in H9c2 cells by the restoration of eNOS and nNOS expressions, mechanistically involving the PI3K/Akt pathway.General significance
This study delineates the underlying mechanisms of opposite NOSs expression in H9c2 cells stimulated with LPS. 相似文献18.
Lifei Chen Chunling Ma Ruiming Wang Jianlou Yang Haijie Zheng 《Biotechnology letters》2016,38(10):1769-1774
Objectives
To improve 1,3-propanediol (1,3-PD) production and reduce byproduct concentration during the fermentation of Klebsiella pneumonia.Results
Klebsiella. pneumonia 2-1ΔldhA, K. pneumonia 2-1ΔaldH and K. pneumonia 2-1ΔldhAΔaldH mutant strains were obtained through deletion of the ldhA gene encoding lactate dehydrogenase required for lactate synthesis and the aldH gene encoding acetaldehyde dehydrogenase involved in the synthesis of ethanol. After fed-batch fermentation, the production of 1,3-PD from glycerol was enhanced and the concentrations of byproducts were reduced compared with the original strain K. pneumonia 2-1. The maximum yields of 1,3-PD were 85.7, 82.5 and 87.5 g/l in the respective mutant strains.Conclusion
Deletion of either aldH or ldhA promoted 1,3-PD production in K. pneumonia.19.
J. Alan Lovatt Richard Hayes Ruth Sanderson Sheena Duller 《Plant Growth Regulation》1990,9(4):353-354
Book Review
The greenhouse effect and UK agricultureR.M. Bennett (Ed.), Reading: Centre for Agricultural Strategy, 1989. 144 pages, paperback. £15.00. ISBN 0-7049-0988-X 相似文献20.