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111.
Beck CR McKenzie BC Hashim AB Harris RC Zanuzdana A Agboado G Orton E Béchard-Evans L Morgan G Stevenson C Weston R Mukaigawara M Enstone J Augustine G Butt M Kim S Puleston R Dabke G Howard R O'Boyle J O'Brien M Ahyow L Denness H Farmer S Figureroa J Fisher P Greaves F Haroon M Haroon S Hird C Isba R Ishola DA Kerac M Parish V Roberts J Rosser J Theaker S Wallace D Wigglesworth N Lingard L Vinogradova Y Horiuchi H Peñalver J Nguyen-Van-Tam JS 《PloS one》2011,6(12):e29249
Background
Immunocompromised patients are vulnerable to severe or complicated influenza infection. Vaccination is widely recommended for this group. This systematic review and meta-analysis assesses influenza vaccination for immunocompromised patients in terms of preventing influenza-like illness and laboratory confirmed influenza, serological response and adverse events.Methodology/Principal Findings
Electronic databases and grey literature were searched and records were screened against eligibility criteria. Data extraction and risk of bias assessments were performed in duplicate. Results were synthesised narratively and meta-analyses were conducted where feasible. Heterogeneity was assessed using I2 and publication bias was assessed using Begg''s funnel plot and Egger''s regression test. Many of the 209 eligible studies included an unclear or high risk of bias. Meta-analyses showed a significant effect of preventing influenza-like illness (odds ratio [OR] = 0.23; 95% confidence interval [CI] = 0.16–0.34; p<0.001) and laboratory confirmed influenza infection (OR = 0.15; 95% CI = 0.03–0.63; p = 0.01) through vaccinating immunocompromised patie nts compared to placebo or unvaccinated controls. We found no difference in the odds of influenza-like illness compared to vaccinated immunocompetent controls. The pooled odds of seroconversion were lower in vaccinated patients compared to immunocompetent controls for seasonal influenza A(H1N1), A(H3N2) and B. A similar trend was identified for seroprotection. Meta-analyses of seroconversion showed higher odds in vaccinated patients compared to placebo or unvaccinated controls, although this reached significance for influenza B only. Publication bias was not detected and narrative synthesis supported our findings. No consistent evidence of safety concerns was identified.Conclusions/Significance
Infection prevention and control strategies should recommend vaccinating immunocompromised patients. Potential for bias and confounding and the presence of heterogeneity mean the evidence reviewed is generally weak, although the directions of effects are consistent. Areas for further research are identified. 相似文献112.
Asif J. Iqbal Daniel Regan-Komito Ivy Christou Gemma E. White Eileen McNeill Amy Kenyon Lewis Taylor Theodore S. Kapellos Edward A. Fisher Keith M. Channon David R. Greaves 《PloS one》2013,8(3)
Chemotaxis assays are an invaluable tool for studying the biological activity of inflammatory mediators such as CC chemokines, which have been implicated in a wide range of chronic inflammatory diseases. Conventional chemotaxis systems such as the modified Boyden chamber are limited in terms of the data captured given that the assays are analysed at a single time-point. We report the optimisation and validation of a label-free, real-time cell migration assay based on electrical cell impedance to measure chemotaxis of different primary murine macrophage populations in response to a range of CC chemokines and other chemoattractant signalling molecules. We clearly demonstrate key differences in the migratory behavior of different murine macrophage populations and show that this dynamic system measures true macrophage chemotaxis rather than chemokinesis or fugetaxis. We highlight an absolute requirement for Gαi signaling and actin cytoskeletal rearrangement as demonstrated by Pertussis toxin and cytochalasin D inhibition. We also studied the chemotaxis of CD14+ human monocytes and demonstrate distinct chemotactic profiles amongst different monocyte donors to CCL2. This real-time chemotaxis assay will allow a detailed analysis of factors that regulate macrophage responses to chemoattractant cytokines and inflammatory mediators. 相似文献
113.
Calabria G Dolgova O Rego C Castañeda LE Rezende EL Balanyà J Pascual M Sørensen JG Loeschcke V Santos M 《Journal of evolutionary biology》2012,25(4):691-700
Theory predicts that geographic variation in traits and genes associated with climatic adaptation may be initially driven by the correlated evolution of thermal preference and thermal sensitivity. This assumes that an organism's preferred body temperature corresponds with the thermal optimum in which performance is maximized; hence, shifts in thermal preferences affect the subsequent evolution of thermal-related traits. Drosophila subobscura evolved worldwide latitudinal clines in several traits including chromosome inversion frequencies, with some polymorphic inversions being apparently associated with thermal preference and thermal tolerance. Here we show that flies carrying the warm-climate chromosome arrangement O(3+4) have higher basal protein levels of Hsp70 than their cold-climate O(st) counterparts, but this difference disappears after heat hardening. O(3+4) carriers are also more heat tolerant, although it is difficult to conclude from our results that this is causally linked to their higher basal levels of Hsp70. The observed patterns are consistent with the thermal co-adaptation hypothesis and suggest that the interplay between behaviour and physiology underlies latitudinal and seasonal shifts in inversion frequencies. 相似文献
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116.
Patricia Molleda Ivan Blanco Gemma Ansola Estanislao de Luis 《Ecological Engineering》2008,33(3-4):252-257
This paper studies the seasonal presence and removal of the pathogenous micro-organisms Escherichia coli, total coliforms (TC), Clostridium perfringens (Cp), faecal streptococci (FS), Giardia cysts, Cryptosporidium oocysts and helminth eggs, in a constructed wetland treatment system. The removal efficiency of this system with respect to the indicator micro-organisms achieved maximum values in spring and autumn at 99.9% for E. coli and TC, respectively, in winter at 97.0% for FS, in summer at 100% for Clostridium and throughout the year, also at 100%, in the case of Giardia cysts, Cryptosporidium oocysts and helminth eggs. In general, very low protozoan and helminth egg counts were found, and the system demonstrated efficient reduction of the wastewater indicator pathogens. 相似文献
117.
Expression of the Bacillus thuringiensis Mosquitocidal Toxin Cry11Aa in the Aquatic Bacterium Asticcacaulis excentricus 总被引:2,自引:0,他引:2
A mosquitocidal aquatic bacterium has been developed by introducing an operon containing the cry11Aa, and p20 genes from Bacillus thuringiensis subsp. israelensis (Bti) into the gram-negative aquatic bacterium Asticcacaulis excentricus. After transformation, the cry11Aa gene was successfully expressed in recombinant A. excentricus under the tac promoter, at the level of 0.04 pg/cell. The recombinant bacteria were toxic to Aedes aegypti larvae with an LC50 of 6.83 × 105 cells/mL. We believe that these bacteria may have potential as genetically engineered microorganisms for the control of mosquito
larvae. 相似文献
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119.
Zampaglione I Arcuri M Cappelletti M Ciliberto G Perretta G Nicosia A La Monica N Fattori E 《The journal of gene medicine》2005,7(11):1475-1481
BACKGROUND: Intramuscular plasmid injection followed by electroporation is an efficient method for gene therapy or vaccination. Several protocols have been described that give good transduction levels with several reporter genes. METHODS: In this work we have explored the efficiency of gene delivery upon variation of the different electrical parameters such as pulse length frequency and voltage monitoring both on short- and long-term protein production. RESULTS: Having defined the best performing parameters, we have designed a short electric treatment that gives good levels of plasmid-encoded protein in different species such as mice, rabbits and monkeys. 相似文献
120.
Eman?Afkar Gemma?RegueraEmail author Marianne?Schiffer Derek?R?Lovley 《BMC microbiology》2005,5(1):41