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Many environmental factors have been associated with an increased risk of developing Rheumatoid Arthritis (RA), but so far smoking is the only environmental risk factor that has been extensively studied and widely accepted. Smoking is associated with an increased risk of developing seropositive RA (RF and/or ACPA). Recent studies show that tobacco smoking can influence disease phenotype, with the development of more aggressive disease and greater joint damage; but other studies show contradictory results. Recent data suggests that response to antirheumatic therapy in RA is worse in smokers. In this article we review different environmental factors that have been associated with an increased risk of developing RA, with a special interest in tobacco smoking.  相似文献   
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Tackling alcohol-related harms crosses agency and professional boundaries, requiring collaboration between health, criminal justice, education and social welfare institutions. It is a key component of most multi-component programmes in the United States, Australia and Europe. Partnership working, already embedded in service delivery structures, is a core mechanism for delivery of the new UK Government Alcohol Strategy. This article reports findings from a study of alcohol partnerships across England. The findings are based on a mix of open discussion interviews with key informants and on semi-structured telephone interviews with 90 professionals with roles in local alcohol partnerships. Interviewees reported the challenges of working within a complex network of interlinked partnerships, often within hierarchies under an umbrella partnership, some of them having a formal duty of partnership. The new alcohol strategy has emerged at a time of extensive reorganisation within health, social care and criminal justice structures. Further development of a partnership model for policy implementation would benefit from consideration of the incompatibility arising from required collaboration and from tensions between institutional and professional cultures. A clearer analysis of which aspects of partnership working provide ‘added value’ is needed.  相似文献   
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BackgroundThere are few data on the bronchodilatory effects of adding short-acting bronchodilators (SABA) to maintenance, long-acting bronchodilator therapy. This study assessed the additional bronchodilation and safety of adding supratherapeutic doses of salbutamol (SALB) or ipratropium bromide (IPR) to the novel bi-functional molecule (or dual pharmacophore) GSK961081 400 μg (MABA 400) or 1200 μg (MABA 1200).MethodsThis randomised, double-blind, complete, crossover study in 44 patients with moderate to severe COPD, evaluated 6 treatments with a washout of at least 7 days between treatments: single doses of MABA 400 or MABA 1200 followed by cumulative doses of either SALB (3× 200 μg at 20 min intervals), IPR (20 μg, 20 μg and 40 μg at 20 min intervals) or placebo (PLA) (three doses at 20 min intervals) at 1 h, 12 h and 24 h post-MABA dose. The primary endpoint was maximal increase in FEV1, from pre-dose bronchodilator (SABA/PLA), measured 15 min after each cumulative dose of SALB, IPR or PLA. Systemic pharmacodynamics (potassium, heart rate, glucose and QTc), adverse events and systemic pharmacokinetics were also assessed.ResultsThe additional bronchodilatory effects at 12 h and 24 h for both SALB and IPR were of a similar magnitude and statistically significant relative to PLA; mean differences (SE) (L) following MABA 400 dosing: 0.139 (0.023) after SALB at 12 h; 0.123 (0.022) after SALB at 24 h; 0.124 (0.023) after IPR at 12 h; 0.141 (0.021) after IPR at 24 h; and after MABA 1200 dosing: 0.091 (0.023) after SALB at 12 h; 0.126 (0.022) after SALB at 24 h; 0.055 (0.023) after IPR at 12 h; 0.122 (0.022) after IPR at 24 h. Any additional bronchodilator effects at 1 h were small and not clinically significantly different from PLA. There were small, non-clinically significant increases in mean heart rate after both MABA doses plus SALB, and decreased potassium levels in four patients after MABA 1200 plus SALB (×3) or PLA (×1) were observed but overall all treatments were well tolerated and raised no significant safety signals.ConclusionThe additional bronchodilation achieved following supratherapeutic doses of SALB and IPR on top of single doses of MABA 400 or 1200 was comparable for the two agents and neither were associated with any clinically relevant systemic pharmacodynamic effects other than the small transient hypokalemic effect in a 3 out of 41 patients receiving additional high dose salbutamol and MABA 1200. Either short-acting bronchodilator could potentially be used as rescue medication on top of MABA therapy.  相似文献   
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Vilanterol (VI; GW642444M) is a novel inhaled long-acting β2-agonist with inherent 24 h activity in vitro in development as a combination with the inhaled corticosteroid fluticasone furoate for both COPD and asthma. These studies were conducted to determine the safety, tolerability, pharmacodynamics and pharmacokinetics of VI in healthy subjects and subjects with mild to moderate persistent asthma and moderate to severe COPD.Single doses of VI (25–100 μg) were given once daily to subjects with asthma and COPD and repeat doses once daily for 14 days to healthy subjects. Adverse events (AEs), vital signs, ECGs, pharmacodynamic endpoints, FEV1 and VI plasma pharmacokinetics (AUC, Cmax and Tmax) were determined following dosing.VI (25–100 μg) was well tolerated. The incidence and severity of AEs were comparable to placebo. Following VI administration there were no clinically significant abnormalities in vital signs, 12-lead ECG, Holter ECG, blood glucose or potassium. There were no statistically significant effects on QTc of single and repeat VI doses up to 50 μg; some differences were seen following the 100 μg VI dose after single and repeat dose in healthy subjects and single dose in asthmatic subjects. All VI doses produced increases in FEV1 from as early as 5 min after dosing which were maintained up to 24 h post-dose in subjects with asthma and COPD. In all subjects VI was rapidly absorbed (healthy subjects median Tmax at 5 min; asthma and COPD subjects median Tmax at 10 min) with systemic exposure increasing in an approximately dose proportional manner across the VI dose range. Marginal accumulation was seen on repeat dosing.Single doses of inhaled VI in subjects with asthma and COPD and repeat doses in healthy subjects were well tolerated with no clinically significant unwanted systemic effects. VI produced a rapid and prolonged bronchodilation over 24 h suggesting the potential for once daily administration.  相似文献   
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Traumatic brain injury (TBI) is often exacerbated by events that lead to secondary brain injury, and represent potentially modifiable causes of mortality and morbidity. Diffusion tensor imaging was used to characterize tissue at-risk in a group of 35 patients scanned at a median of 50 hours after injury. Injury progression was assessed in a subset of 16 patients with two scans. All contusions within the first few days of injury showed a core of restricted diffusion, surrounded by an area of raised apparent diffusion coefficient (ADC). In addition to these two well-defined regions, a thinner rim of reduced ADC was observed surrounding the region of increased ADC in 91% of patients scanned within the first 3 days after injury. In patients who underwent serial imaging, the rim of ADC hypointensity was subsumed into the high ADC region as the contusion enlarged. Overall contusion enlargement tended to be more frequent with early lesions, but its extent was unrelated to the time of initial imaging, initial contusion size, or the presence of hemostatic abnormalities. This rim of hypointensity may characterize a region of microvascular failure resulting in cytotoxic edema, and may represent a ‘traumatic penumbra'' which may be rescued by effective therapy.  相似文献   
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