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101.

Background

The six most important cost-effective policies on tobacco control can be measured by the Tobacco Control Scale (TCS). The objective of our study was to describe the correlation between the TCS and smoking prevalence, self-reported exposure to secondhand smoke (SHS) and attitudes towards smoking restrictions in the 27 countries of the European Union (EU27).

Methods/Principal Findings

Ecologic study in the EU27. We used data from the TCS in 2007 and from the Eurobarometer on Tobacco Survey in 2008. We analysed the relations between the TCS and prevalence of smoking, self-reported exposure to SHS (home and work), and attitudes towards smoking bans by means of scatter plots and Spearman rank-correlation coefficients (rsp). Among the EU27, smoking prevalence varied from 22.6% in Slovenia to 42.1% in Greece. Austria was the country with the lowest TCS score (35) and the UK had the highest one (93). The correlation between smoking prevalence and TCS score was negative (rsp = −0.42, p = 0.03) and the correlation between TCS score and support to smoking bans in all workplaces was positive (rsp = 0.47, p = 0.01 in restaurants; rsp = 0.5, p = 0.008 in bars, pubs, and clubs; and rsp = 0.31, p = 0.12 in other indoor workplaces). The correlation between TCS score and self-reported exposure to SHS was negative, but statistically non-significant.

Conclusions/Significance

Countries with a higher score in the TCS have higher support towards smoking bans in all workplaces (including restaurants, bars, pubs and clubs, and other indoor workplaces). TCS scores were strongly, but not statistically, associated with a lower prevalence of smokers and a lower self-reported exposure to SHS.  相似文献   
102.
The continuing identification and elucidation of the molecular defects involved in mesothelioma pathogenesis and progression should lead to better disease control and greater therapeutic options in the near future. Goal of this review article is to summarize the most recent advances in molecular pathogenesis of mesothelioma and discuss possible therapeutic implications of these findings.  相似文献   
103.
The natural history and pathogenic potential of the recently identified TT virus (TTV) are currently a matter of intensive investigation. In an attempt to shed some light on these issues, nasal and blood specimens of 1- to 24-month-old children hospitalized with a clinical diagnosis of acute respiratory disease (ARD) were examined for the presence, load, and genetic characteristics of TTV. The results have indicated that at least in young children, the respiratory tract not only represents a route by which abundant TTV can be shed into the environment but also may be a site of primary infection and continual replication. Although we found no compelling evidence that TTV was the direct cause of ARD in some of the children studied, the average loads of TTV were considerably higher in patients with bronchopneumonia (BP) than in those with milder ARD, raising interesting questions about the pathophysiological significance of TTV at this site. Furthermore, group 4 TTV was detected almost exclusively in children with BP.  相似文献   
104.
TT virus (TTV) produces chronic plasma viremia in around 90% of healthy individuals of all ages and has, therefore, been proposed as a commensal human virus. We recently demonstrated that in children hospitalized for acute respiratory diseases high TTV loads were associated with severe forms of disease. Here, we report that in such children TTV loads showed an inverse correlation with the percentage of circulating total T and helper T cells and a direct correlation with the percentage of B cells. Thus, florid TTV replication might contribute to lymphocyte imbalances and, possibly, immunosuppressive effects, thus resembling related animal viruses.  相似文献   
105.
Aphanizomenon flos-aquae (AFA) is a fresh water unicellular blue-green alga (cyanophyta) rich in phycocyanin (PC), a photosynthetic pigment with antioxidant and anti-inflammatory properties. The purpose of this study was to evaluate the ability of a novel natural extract from AFA enriched with PC to protect normal human erythrocytes and plasma samples against oxidative damage in vitro. In red blood cells, oxidative hemolysis and lipid peroxidation induced by the aqueous peroxyl radical generator [2,2'-Azobis (2-amidinopropane) dihydrochloride, AAPH] were significantly lowered by the AFA extract in a time- and dose-dependent manner; at the same time, the depletion of cytosolic glutathione was delayed. In plasma samples, the natural extract inhibited the extent of lipid oxidation induced by the pro-oxidant agent cupric chloride (CuCl2); a concomitant increase of plasma resistance to oxidation was observed as evaluated by conjugated diene formation. The involvement of PC in the antioxidant protection of the AFA extract against the oxidative damage was demonstrated by investigating the spectral changes of PC induced by AAPH or CuCl2. The incubation of the extract with the oxidizing agents led to a significant decrease in the absorption of PC at 620 nm accompanied with disappearance of its blue color, thus indicating a rapid oxidation of the protein. In the light of these in vitro results, the potential clinical applications of this natural compound are under investigation.  相似文献   
106.
A battery of in vitro short-term tests revealing different genetic end-points was set up in order to study surface-water genotoxicity after disinfection with different biocides: sodium hypochlorite (NaClO), chlorine dioxide (ClO(2)) and peracetic acid (PAA). The surface water both before and after disinfection was concentrated by adsorption on C(18) silica cartridges and the concentrates containing non-volatile organics were divided into different portions for chemical analyses and biological assays. The following in vitro tests were conducted on the water concentrates dissolved in DMSO: the Salmonella mutagenicity assay with S. typhimurium strains TA98 and TA100; the SOS Chromotest with Escherichia coli, the Microtox and Mutatox assays with Vibrio fischeri; and gene conversion, point mutation and mitochondrial DNA mutability assays with D7 diploid Saccharomices cerevisiae strain. The results show that the SOS Chromotest and the yeast assays are highly sensitive in detecting genotoxicity. The surface-water extracts were very often toxic to most of the test organisms considered, partially masking their potential mutagenic activity. Therefore, the assays with E. coli and with S. cerevisiae are more likely to show a mutagenic effect because these organisms are generally less sensitive to most toxic compounds. Among the tested disinfectants, NaClO and ClO(2) increased water genotoxicity, whereas PAA was able to slightly reduce raw water activity. However, because the organic compounds in the lake water varied with the season of the year, the disinfection processes, at times, both increased and decreased the raw water activity.  相似文献   
107.
We have examined the issue of whether or not in PC12 cells it may be observed a nerve growth factor (NGF) nuclear translocation of an active (phosphorylated) Akt. Western blot analysis with antibodies to either total or phosphorylated Akt showed a maximal nuclear translocation after 15 min of NGF stimulation. NGF increased rapidly and transiently the enzymatic activity of immunoprecipitable nuclear Akt and after 45 min the values returned to a level close to the basal one. Enzyme translocation was blocked by the selective phosphoinositide 3-kinase inhibitor, LY294002. Confocal microscopy of samples stained with antibody to Akt showed an evident increase in immunostaining intensity in the nuclear interior after NGF treatment. Treatment of cells with inhibitors of protein phosphatase PP2A, calyculin A, or okadaic acid, maintained the phosphorylation levels of nuclear Akt. Immunoprecipitation experiments revealed an association between Akt and PP2A that was maximal when nuclear Akt activity was decreased. Both total and active Akt associated with the nuclear matrix and, in particular, with the protein nucleolin, with which Akt co-immunoprecipitated. These findings strongly suggest that the intranuclear translocation of active Akt is an important step in the signaling pathways elicited by the neurotrophin NGF and that the intranuclear control of Akt is achieved through the action of PP2A.  相似文献   
108.
IL-12 and IL-15 stimulate T, B, and NK cell functions through independent mechanisms, and cooperative effects of these cytokines have been reported. The human MHC class I-negative small cell lung cancer cell line, N592, genetically engineered to secrete IL-15, N592/IL-15, showed a reduced tumor growth rate, while N592 cells engineered with IL-12, N592/IL-12, grew similarly to the wild-type N592, N592 parental cells (N592pc), in nude mice. However, N592 cells coexpressing both cytokines, N592/IL-12/IL-15 cells, were completely rejected by 100% of nude mice. Here we show that 60% of nude mice rejecting N592/IL-12/IL-15 cells were resistant to N592pc rechallenge. SCID mice rejected N592/IL-12/IL-15 cells, but did not develop resistance to N592pc rechallenge, suggesting a role of Ab responses. Among nude mice rejecting N592/IL-12/IL-15 cells, those developing resistance to N592pc rechallenge had significantly higher titers of anti-N592 IgG2b Abs than nonresistant nude mice. Induction of an Ig class switch in nude mice was related to the expression of IFN-gamma and CD40 ligand in the draining lymph nodes. An IgG2b, anti-N592 mAb, derived from N592/IL-12/IL-15-immunized nude mice splenocytes induced significant protection against N592pc, while an IgM mAb was ineffective. The protective IgG2b mAb, but not the IgM mAb, triggered Ab-dependent cell-mediated cytotoxicity by nude mouse splenocytes against N592pc. These data indicate that IL-12 and IL-15 synergistically trigger innate, immunity-mediated, anti-tumor effects, resulting in cytotoxic IgG Ab responses in T cell-deficient mice. Protective Ab responses may relate to both direct actions of IL-12 and IL-15 on B cells and to the activation of an innate immunity-B cell cross-talk.  相似文献   
109.
Sexual differences in the foraging behaviour of parents have been observed in a number of sexually sizedimorphic birds, particularly seabirds, and the usual inference has been that these sex-specific differences are mediated primarily by differences in body size. To test this explanation, we compared the foraging behaviour of parents in a monomorphic seabird species, the northern gannet Morus bassanus. Using specially designed instruments and radio telemetry we found that individuals of both sexes were consistent in the directions and durations of their foraging trips. However, there were significant differences in the foraging behaviour of males and females. Female gannets were not only more selective than males in the areas where they foraged, but they also made longer, deeper dives and spent more time on the sea surface than males. As the sexes are morphologically similar in this species, then these differences are unlikely to have been mediated by body size. Our work highlights the need to investigate sexual differences in the foraging behaviour of seabirds and other species more closely, in order to test alternative theories that do not rely on differences in body size.  相似文献   
110.
Thioredoxin specifically cross-desensitizes monocytes to MCP-1   总被引:1,自引:0,他引:1  
Thioredoxin (Trx) is a protein disulfide oxidoreductase which can be secreted and acts as a cytokine. As we recently reported that Trx is chemotactic, we investigated whether it desensitizes monocytes or PMN to other chemokines. Preincubation for 15 min with Trx inhibited the chemotactic response of monocytes to MCP-1, but not to fMLP. This effect was independent of whether Trx was present during the chemotaxis assay or only during the preincubation. Preincubation (5 min) with Trx also inhibited the increase in intracellular Ca(2+) induced by MCP-1 in monocytes, but not that induced by fMLP. Preincubation with Trx did not affect the chemotactic response induced in PMN by IL-8. The inhibition of chemotactic and Ca(2+) responses to MCP-1 in monocytes was not due to a down-regulation of the MCP-1 receptor, as shown by receptor binding studies. The Ca(2+) response to MCP-1 was also inhibited by Trx in a CCR2-transfected cell line. It is suggested that Trx inhibits monocyte responses to chemokines by acting downstream of the chemokine receptors. Since there are high concentrations of circulating Trx in infection and inflammatory diseases, this might act as an inhibitor of monocyte migration in vivo.  相似文献   
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