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1.
Chronic obstructive pulmonary disease (COPD) is a prevalent condition in adults aged ≥40 years characterized by progressive airflow limitation associated with chronic inflammatory response to noxious particles in the airways and lungs. Smoking, genetics, air pollution, nutrition and other factors may influence COPD development. Most hospitalizations and deaths for COPD are caused by its acute exacerbations, which greatly affect the health and quality of life of COPD patients and pose a high burden on health services. The aims of this project were to identify trends, geographic patterns and risk factors for COPD exacerbations, as revealed by hospitalizations and deaths, in the Basque Country, Spain, over a period of 12 years (2000–2011). Hospitalization and mortality rates for COPD were 262 and 18 per 100,000 population, respectively, with clusters around the biggest cities. Hospital mortality was 7.4%. Most hospitalized patients were male (77.4%) and accounted for 72.1% of hospital mortality. Hospitalizations decreased during the study period, except for 50–64 year-old women, peaking significantly. Using a multivariate modeling approach it was shown that hospitalizations were positively correlated with increased atmospheric concentrations of NO2, CO, PM10, and SO2, and increased influenza incidence, but were negatively associated with increased temperatures and atmospheric O3 concentration. COPD exacerbations decreased in the Basque Country during 2000–2011, but not among 50–64-year-old women, reflecting the high smoking prevalence among Spanish women during the 1970–1990s. The main metropolitan areas were those with the highest risk for COPD exacerbations, calling attention to the role of heavy car traffic. Influenza virus, cold temperatures, and increased atmospheric NO2, CO, PM10, and SO2 (but decreased O3) concentrations were identified as potential contributors to the burden of COPD exacerbations in the community. These findings are important for both the understanding of the disease process and in providing potential targets for COPD-reducing initiatives and new avenues for research.  相似文献   
2.
Although mesenchymal stromal cells (MSCs) possess the capacity to modulate immune responses, little is known about the mechanisms that underpin these processes. In this study, we show that immunosupression is mediated by activation of nuclear factor kappa B (NF‐κB) in human MSCs. This pathway is activated by TNF‐α that is generated following TCR stimulation of T cells. Inhibition of NF‐κB through silencing of IκB kinase β or the TNF‐α receptor abolishes the immunosuppressive capacity of MSCs. Our data also indicate that MSC‐associated NF‐κB activation primarily leads to inhibition of T‐cell proliferation with little effect on expression of the activation markers CD69 and CD25. Thus, our data support the hypothesis that the TNF‐α/NF‐κB signalling pathway is required for the initial priming of immunosuppressive function in human MSCs. Interestingly, drugs that interfere with NF‐κB activation significantly antagonise the immunoregulatory effect of MSCs, which could have important implications for immunosuppression regimens in the clinic.  相似文献   
3.
The synthesis of two series of 1-(but-2-ynyl)pyrazole containing a pyrrolidine or a diethylamine moiety, respectively, is described, together with their muscarinic receptor affinities.  相似文献   
4.
We evaluated the in vitro capacity of high and low molecular weight chitosans (HMWCh and LMWCh) to inhibit the adherence of strains of S. mutans obtained from the American Type Culture Collection (ATCC,25175) to artificial saliva-coated hydroxiapatite beads. The effect of these biopolymers was assessed in terms of pH, ionic force, minimum inhibitory concentration (MIC) and antibacterial activity. The results show that HMWCh is modified by a rise in pH (7.0) and ionic strength. The induced conformational changes lead to the formation of rigid meshes capable of aggregating and entrapping S. mutans. This process is associated to the properties of HMWCh. LMWCh gave rise to smaller aggregates that exhibited a comparatively reduced interaction capacity. The MIC for HMWCh was 0.5 g% and evidenced the bacteriostatic action of the aggregates. We conclude that HMWCh would exert an inhibitory effect on the process of specific adsorption of S. mutans to saliva-coated hydroxiapatite beads.  相似文献   
5.
The synthesis of new N-(4-pyridyl)-1-aminopyrazoles is described. Their binding properties were tested for muscarinic and other neurotransmitter receptors, together with their acetylcholinesterase inhibitory activity. The series derived from 3,5-dimethyl-1H-pyrazole showed moderate activities in both muscarinic and adrenergic receptor binding tests.  相似文献   
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The epidemiological situation of HIV infection and AIDS in Navarre in 2003 is reviewed. Up until December 2003, 1,610 HIV infections had been diagnosed in residents of Navarre, of whom 41% had died. The new diagnoses of HIV fell by some 81% between 1993 and 2003, a year in which 28 cases were diagnosed (4.8 per 100,000 inhabitants). The fall basically occurred in infections in injection drug users, since the cases due to sexual transmission had remained stable. Over half of the infections diagnosed in the period 2000-2003 (58%) were attributable to heterosexual transmission, 18% occurred in parenteral drug users and 12% in homosexual men. Thirty-three percent were persons originally from other countries. The incidence of AIDS fell from 75 cases in 1996 to 20 in 2003, and mortality from 65 to 8 cases, respectively. In the 2000-2003 period, the average annual incidence of AIDS was 4.2 per 100,000 inhabitants and the average annual rate of mortality was 1.6 per 100,000 inhabitants. At the end of 2003, there were 902 living persons with a diagnosis of HIV monitored by the health system (1.6 known infections per 1,000 inhabitants). In 2003, 65% of the youths aged between 15 and 29 referred to coital sexual relations, a higher percentage than in previous years, but their level of information on the prevention of AIDS was acceptable. It is necessary to insist on prevention and to adapt this to the new situation.  相似文献   
8.
A cross-sectional study was conducted within the Spanish cohort of the European Prospective Investigation in Cancer and Nutrition to assess the principal food sources of vitamin C, vitamin E, alpha-carotene, beta-carotene, lycopene, lutein, beta-cryptoxanthin and zeaxanthin in an adult Spanish population. The study included 41446 healthy volunteers (25812 women and 15634 men), aged 29-69 years, from three Spanish regions in the north (Asturias, Navarra and Guipúzcoa) and two in the south (Murcia and Granada). Usual food intake was estimated by personal interview through a computerized version of a dietary history questionnaire. Foods that provided at least two-thirds of the studied nutrients were: fruits (mainly oranges) (51 %) and fruiting vegetables (mainly tomato and sweet pepper) (20 %) for vitamin C; vegetable oils (sunflower and olive) (40 %), non-citrus fruits (10 %), and nuts and seeds (8 %) for vitamin E; root vegetables (carrots) (82 %) for alpha-carotene; green leafy (28 %), root (24 %) and fruiting vegetables (22 %) for beta-carotene; fruiting vegetables (fresh tomato) (72 %) for lycopene; green leafy vegetables (64 %) for lutein; citrus fruits (68 %) for beta-cryptoxanthin; citrus fruits (43 %) and green leafy vegetables (20 %) for zeaxanthin. In conclusion, the main food sources of nutrients with redox properties have been identified in a Mediterranean country. This could provide an insight into the interpretation of epidemiological studies investigating the role of diet in health and disease.  相似文献   
9.
Smoking has recently been recognised as causally associated with the development of gastric cancer (GC). However, evidence on the effect by sex, duration and intensity of smoking, anatomic subsite and cessation of smoking is limited. Our objective was to assess the relation between tobacco use and GC incidence in the European Prospective Investigation into Cancer and Nutrition (EPIC). We studied data from 521,468 individuals recruited from 10 European countries taking part in the EPIC study. Participants completed lifestyle questionnaires that included questions on lifetime consumption of tobacco and diet in 1991-1998. Participants were followed until September 2002, and during that period 305 cases of stomach cancer were identified. After exclusions, 274 were eligible for the analysis, using the Cox proportional hazard model. After adjustment for educational level, consumption of fresh fruit, vegetables and preserved meat, alcohol intake and body mass index (BMI), there was a significant association between cigarette smoking and gastric cancer risk: the hazard ratio (HR) for ever smokers was 1.45 (95% confidence interval [CI] = 1.08-1.94). The HR of current cigarette smoking was 1.73 (95% CI = 1.06-2.83) in males and 1.87 (95% CI = 1.12-3.12) in females. Hazard ratios increased with intensity and duration of cigarette smoked. A significant decrease of risk was observed after 10 years of quitting smoking. A preliminary analysis of 121 cases with identified anatomic site showed that current cigarette smokers had a higher HR of GC in the cardia (HR = 4.10) than in the distal part of the stomach (HR = 1.94). In this cohort, 17.6 % (95% CI = 10.5-29.5 %) of GC cases may be attributable to smoking. Findings from this large study support the causal relation between smoking and gastric cancer in this European population. Stomach cancer should be added to the burden of diseases caused by smoking.  相似文献   
10.
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