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911.

Background

In the third season of I-MOVE (Influenza Monitoring Vaccine Effectiveness in Europe), we undertook a multicentre case-control study based on sentinel practitioner surveillance networks in eight European Union (EU) member states to estimate 2010/11 influenza vaccine effectiveness (VE) against medically-attended influenza-like illness (ILI) laboratory-confirmed as influenza.

Methods

Using systematic sampling, practitioners swabbed ILI/ARI patients within seven days of symptom onset. We compared influenza-positive to influenza laboratory-negative patients among those meeting the EU ILI case definition. A valid vaccination corresponded to > 14 days between receiving a dose of vaccine and symptom onset. We used multiple imputation with chained equations to estimate missing values. Using logistic regression with study as fixed effect we calculated influenza VE adjusting for potential confounders. We estimated influenza VE overall, by influenza type, age group and among the target group for vaccination.

Results

We included 2019 cases and 2391 controls in the analysis. Adjusted VE was 52% (95% CI 30-67) overall (N = 4410), 55% (95% CI 29-72) against A(H1N1) and 50% (95% CI 14-71) against influenza B. Adjusted VE against all influenza subtypes was 66% (95% CI 15-86), 41% (95% CI -3-66) and 60% (95% CI 17-81) among those aged 0-14, 15-59 and ≥60 respectively. Among target groups for vaccination (N = 1004), VE was 56% (95% CI 34-71) overall, 59% (95% CI 32-75) against A(H1N1) and 63% (95% CI 31-81) against influenza B.

Conclusions

Results suggest moderate protection from 2010-11 trivalent influenza vaccines against medically-attended ILI laboratory-confirmed as influenza across Europe. Adjusted and stratified influenza VE estimates are possible with the large sample size of this multi-centre case-control. I-MOVE shows how a network can provide precise summary VE measures across Europe.  相似文献   
912.
Given the high morbidity and mortality rates associated with pulmonary inflammation in sepsis, there is a pressing need for new therapeutic modalities to prevent acute respiratory distress. The enzyme heme oxygenase-1 (HO-1) provides potent cytoprotection against lung injury; however, the mechanism by which it does so is unclear. HO-1 catabolizes heme into biliverdin (BV), which is rapidly converted to bilirubin by BV reductase. We tested the hypothesis that BV administration could substitute for the effects observed with HO-1. Using the well-described rat model of LPS-induced shock, we demonstrate that exposure to BV imparts a potent defense against lethal endotoxemia systemically, as well as in the lungs, and effectively abrogates the inflammatory response. BV administration before a lethal dose of LPS leads to a significant improvement in long-term survival: 87% vs. 20% in sham-treated controls. BV treatment suppressed LPS-induced increases in lung permeability and lung alveolitis and significantly reduced serum levels of the LPS-induced proinflammatory cytokine IL-6. Moreover, bilirubin administered just after LPS also abrogated lung inflammation. BV treatment also augmented expression of the anti-inflammatory cytokine IL-10. Similar effects on production were observed with BV treatment in vitro in mouse lung endothelial cells and RAW 264.7 macrophages treated with LPS. In conclusion, these data demonstrate that BV can modulate the inflammatory response and suppress pathophysiological changes in the lung and may therefore have therapeutic application in inflammatory disease states of the lung.  相似文献   
913.
BackgroundThe disordered Tubulin Polymerization Promoting Protein/p25 (TPPP/p25) modulates the dynamics and stability of the microtubule system. In this paper the role of dimerization in its microtubule-related functions is established, and an approach is proposed to evaluate thermodynamic constants for multiple equilibrium systems from ITC measurements.MethodsFor structural studies size exclusion chromatography, SDS-PAGE, chemical cross-linking, circular dichroism, fluorescence spectroscopy and isothermal titration calorimetry were used; the functional effect was analyzed by tubulin polymerization assay. Numerical simulation of the multiple equilibrium was performed with Mathematica software.ResultsThe dimerization of TPPP/p25 is promoted by elevation of the protein concentration and by GTP addition. The dimeric form displaying enhanced tubulin polymerization promoting activity is stabilized by disulfide bond or chemical cross-linking. The GTP binding to the dimeric form (Kd-GTP = 200 μM) is tighter with one order of magnitude than to the monomeric one leading to the enrichment of the dimers. A mathematical model elaborated for the multiple equilibrium of the TPPP/p25-GTP system was validated by fitting the GTP-dependent changes of ellipticity and fluorescence signal in the course of TPPP/p25 titrations. The evaluation of the equilibrium constants rendered it possible to determine the thermodynamic parameters of the association of different TPPP/p25 forms with GTP from ITC measurements.Conclusions/General SignificanceThe dimerization of TPPP/p25 with favorable physiological functional potency is proposed to play significant role in the fine tuning of TPPP/p25-mediated microtubule assembly; the unfolded monomers might be involved in the formation of pathological inclusions characteristic for Parkinson's disease and other synucleinopathies.  相似文献   
914.
Laccase-producing fungi were isolated from air, using selective media with a chromogenic substrate to indicate enzyme activity. The best laccase producer strain proved to be a Leptosphaerulina chartarum isolate. Laccase production was investigated in the presence of various inducers in different cultivation conditions. The extracellular laccase was purified for further investigations. SDS-PAGE showed that this laccase is a monomeric protein of 38 kDa molecular weight. The enzyme is active in the pH-range of 3.5–6, with an optimum at pH 3.8. It is active in the 10–60 °C temperature range, with an optimum at 40 °C. After 20 min incubation at temperatures above 70 °C the enzyme lost its activity. Degradation of seven aniline and phenol compounds (2,4-dichlorophenol; 2-methyl-4-chlorophenol; 3-chloroaniline; 4-chloroaniline; 2,6-dimethylaniline; 3,4-dichloroaniline and 3-chloro-4-methylaniline) was investigated, with or without guaiacol (2-methoxyphenol) as mediator molecule. Addition of a mediator to the system significantly increased the degradation levels. These results confirmed that the isolated laccase is able to convert these harmful xenobiotics at in vitro conditions.  相似文献   
915.
Habitat fragmentation threatens the survival of many species and local populations. Habitat fragmentation has two major consequences: populations become more isolated and are reduced in size. Small compared with large populations have increased extinction risks because of different types stochasticity (e.g. genetic drift) and inbreeding, which can negatively affect the fitness of individuals or populations. Habitat fragmentation may also change the abiotic conditions of the surrounding landscape, which influences biotic interactions. This review gives an introduction to the theory of the effects of habitat fragmentation on mean fitness of plant populations. It intends to help bridge the gap between conservation biologists and conservation practitioners. The paper shortly introduces basic concepts of population biology, demography and genetics and cites relevant and new literature. Special attention is given to more common plant species, which have attracted far less conservation attention than rare species.  相似文献   
916.
917.
918.
Dendrobium is a large genus in the family Orchidaceae that exhibits vast diversity in floral characteristics, which is of considerable importance to orchid breeders, biotechnologists and collectors. Native species have high value as a result of their medicinal properties, while their hybrids are important as ornamental commodities, either as cut flowers or potted plants and are thus veritable industrial crops. Thus, preservation of Dendrobium germplasm is valuable for species conservation, breeding programs and the floriculture industry. Cryopreservation represents the only safe, efficient and cost-effective long-term storage option to facilitate the conservation of genetic resources of plant species. This review highlights 16 years of literature related to the preservation of Dendrobium germplasm and comprises the most comprehensive assessment of thorough studies performed to date, which shows reliable and reproducible results. Air-drying, encapsulation–dehydration, encapsulation–vitrification, vitrification and droplet-vitrification are the current cryopreservation methodologies that have been used to cryopreserve Dendrobium germplasm. Mature seeds, pollen, protoplasts, shoot primordia, protocorms and somatic embryos or protocorm-like bodies (PLBs) have been cryopreserved with different levels of success. Encapsulation–vitrification and encapsulation–dehydration are the most used protocol, while PLBs represent the main explant explored.  相似文献   
919.
Objective: To determine the variation in preadipocyte isolation procedure and to assess the number and function of preadipocytes from subcutaneous and omental adipose tissue of obese individuals. Research Methods and Procedures: The preadipocyte number per gram of adipose tissue in the abdominal‐subcutaneous and abdominal‐omental adipose stores of 27 obese subjects with a BMI of 44 ± 10 kg/m2 and an age of 40 ± 9 years was determined. Results: The assessment of the preadipocyte number was found to be labor intensive and error prone. Our data indicated that the number of stromal vascular cells (SVCs), isolated from the adipose tissue by collagenase digestion, was dependent on the duration of collagenase treatment and the size and the origin of the biopsy. In addition, the fat accumulation and leptin production by differentiated SVCs were dependent on the number of adherent SVCs (aSVCs) in the culture plate and the presence of proteins derived from serum and peroxisome proliferator‐activated receptor ligands. Discussion: Using our standardized isolation and differentiation protocol, we found that the number of SVCs, aSVCs, leptin production, and fat accumulation still varied considerably among individuals. Interestingly, within individuals, the number of SVCs, aSVCs, and the leptin production by differentiating aSVCs from both the subcutaneous and the omental fat depots were associated, whereas fat accumulation was not. In obese to severely obese subjects, differences in BMI and age could not explain differences in SVCs, aSVCs, leptin production, and fat accumulation.  相似文献   
920.
The cytotoxic effect of 5-fluorouracil (5-FU) is mediated by the inhibition of thymidylate synthase (TS), however, at the same time 5-FU is catabolized by dihydropyrimidine dehydrogenase (DPD). Efficacy of 5-FU may therefore depend on the TS and DPD activity and on pharmacogenetic factors influencing these enzymes. Our aims were (1) to determine the distribution of DPD activity, the frequency of DPD deficiency and the DPD (IVS14+1G>A) mutation in the peripheral blood mononuclear cells of colorectal cancer (CRC) patients, and study the relationship between DPD deficiency and toxicity of 5-FU; (2) to investigate the influence of TS polymorphisms and DPD activity on the survival of CRC patients receiving 5-FU-based adjuvant therapy. The frequency of DPD deficiency was determined by radiochemical methods in the peripheral blood mononuclear cells (PBMCs) of 764 CRC patients treated with 5-FU. The relationship between the TS polymorphisms, DPD activity and the disease-free and overall survival was studied in 166 CRC patients receiving 5-FU-based adjuvant therapy. TS polymorphisms were determined in the DNA samples separated from the PBMCs, by PCR-PAGE and PCR-RFLP-PAGE (restriction fragment length polymorphism) methods. Low DPD values (<10 pmol/min/106 PBMCs) were demonstrated in 160/764 patients (20.9%), and of those DPD deficiency (<5 pmol/min/106 PBMCs) was verified in 38 patients (4.9%). In the latter group severe (>Gr 3) toxicity was found in 87%. The prevalence of the DPD IVS14+1G>A mutation among the 38 DPD-deficient patients was 7.8% (3/38) and was accompanied by severe Gr 4 toxic symptoms (neutropenia, mucositis, diarrhea). TS polymorphisms showed a relationship with the survival of CRC patients. It is important to mention that by combining the 3-3 genotypes of 5'-TSER and 3'-TSUTR polymorphisms the obtained 8 genotype combinations showed significantly different Kaplan-Meier survival curves. The evaluation of these curves with Cox regression analysis resulted in two prognostically different groups: "A" good prognosis (RR<1) and "B" bad prognosis (RR>1). The disease-free- and overall survival of these two groups were significantly different. DPD activity also showed correlation with the survival; patients with DPD activity <10 pmol/min/106 PBMCs showed significantly longer disease-free and overall survival. The determination of DPD activity proved to be a more valuable parameter in the evaluation of serious 5-FU-related toxicity compared to the IVS14+1G>A mutation analysis. According to the Cox multivariate analysis the combination of germline TS polymorphisms and DPD activity is/an independent prognostic marker of survival in CRC patients treated with adjuvant 5-FU therapy.  相似文献   
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