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AIMS: To assess the short-term impact of smoking and smoking cessation measured by self-report and by serum cotinine on the risk of secondary cardiovascular disease events (CVD events). METHODS AND RESULTS: Cohort study among participants of an in-patient 3-week rehabilitation programme following an acute coronary syndrome or coronary artery revascularization. Smoking status at baseline was assessed by self-report (beginning of the rehabilitation programme, rehab) and serum cotinine (end of rehab). Active follow-up was conducted one year later. Subsequent CVD events were observed in 139 of the 967 patients. Both self-reported smoking status (odds ratio (OR) compared to continued smokers: recent quitters 0.96, former smokers 0.83, never smokers 0.54, p for trend 0.04) and serum cotinine (OR 0.59 (95% confidence interval (CI) 0.36-0.97) for cotinine-negative compared to cotinine-positive subjects) were associated with the occurrence of a secondary CVD event. After reclassification of all cotinine-positive subjects to continued smokers and cotinine-negative self-reported smokers to recent quitters, this association became even stronger. The OR now reached 0.71 (95% CI interval 0.38-1.33) for recent quitters, 0.64 (0.36-1.11) for former smokers and 0.44 (0.24-0.81) for never smokers (p-value for trend=0.009). CONCLUSION: The benefits of non-smoking and smoking cessation in cardiac patients are beyond controversy and might even be larger than suggested by previous studies which exclusively relied on self-reported smoking status.  相似文献   
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INTRODUCTION: The prevalence of childhood obesity is increasing with its negative medical and psychosocial consequences. This paper examines the association between body mass index (BMI), motor abilities and leisure habits of 668 children within the CHILT (Children's Health InterventionaL Trial) project. METHOD: A total of 668 children (51.0% boys; 49.0% girls) and their parents were questioned on sport and leisure behaviour of the children. The anthropometric data were measured. Motor abilities were determined by a body gross motor development test for children (K?perkoordinationstest für Kinder; KTK) and a 6-min run. RESULTS: The children were 6.70 +/- 0.42 y old, 122.72 +/- 5.36 cm tall and weighed 24.47 +/- 4.59 kg, the average BMI was 16.17 +/- 2.27 kg/m2. KTK showed an average motor quotient (MQ) of 93.49 +/- 15.01, the 6-min run an average of 835.24 +/- 110.87 m. Both tests were inversely correlated with BMI (KTK and BMI r=-0.164 (P<0.001); 6-min run and BMI r=-0.201 (P<0.001)); the group of overweight/obese children showed poorer results than the normal/underweight ones, even after adjustment for gender and age (in each case P<0.001). Children with the greatest extent of exercise achieve the highest MQ (P=0.035). SUMMARY: Overweight/obesity is associated with a poorer body gross motor development and endurance performance. On the other hand, an active lifestyle is positively correlated with a better gross motor development in first-grade children. Therefore, to prevent the negative consequences of physical inactivity and overweight/obesity early intervention to support exercise and movement is recommended.  相似文献   
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It has long been established that the absorption of short-chain fatty acids (SCFA) across epithelia stimulates sodium proton exchange. The apically released protons are not available as countercations for the basolateral efflux of SCFA anions and a suitable transport model is lacking. Patch clamp and microelectrode techniques were used to characterize an anion conductance expressed by cultured cells of the sheep and bovine rumen and the sheep omasum and to localize the conductance in the intact tissue. Cells were filled with a Na-gluconate solution and superfused with sodium salts of acetate, propionate, butyrate, or lactate. Reversal potential rose and whole cell current at +100 mV decreased with the size of the anion. Anion-induced currents could be blocked by diisothiocyanato-stilbene-2,2′-disulfonic acid (DIDS), NPPB (200?μmol l?1), or pCMB (1 mmol l?1). In patches of bovine ruminal cells, single channels were observed with a conductance for chloride (327?±?11 pS), acetate (115?±?8 pS), propionate (102?±?10 pS), butyrate (81?±?2 pS), and gluconate (44?±?3 pS). Channels expressed by sheep rumen and omasum were similar. Microelectrode experiments suggest basolateral localization. In conclusion, forestomach epithelia express basolateral maxi-anion channels with a permeability sequence of chloride?>?acetate?>?propionate?>?butyrate. SCFA absorption may resemble functionally coupled transport of NaCl, with the Na+/K+-ATPase driving the basolateral efflux of the anion through a channel. Since protons are apically extruded, the model accurately predicts that influx of buffers with saliva is essential for the pH homeostasis of the ruminant forestomach.  相似文献   
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Antibiotic resistance, especially in gram-negative bacteria, is spreading globally and rapidly. Development of new antibiotics lags behind; therefore, novel approaches to the problem of antibiotic resistance are sorely needed and this commentary highlights one relatively unexplored target for drug development: conjugation. Conjugation is a common mechanism of horizontal gene transfer in bacteria that is instrumental in the spread of antibiotic resistance among bacteria. Most resistance genes are found on mobile genetic elements and primarily spread by conjugation. Furthermore, conjugative elements can act as a reservoir to maintain antibiotic resistance in the bacterial population even in the absence of antibiotic selection. Thus, conjugation can spread antibiotic resistance quickly between bacteria of the microbiome and pathogens when selective pressure (antibiotics) is introduced. Potential drug targets include the plasmid-encoded conjugation system and the host-encoded proteins important for conjugation. Ideally, a conjugation inhibitor will be used alongside antibiotics to prevent the spread of resistance to or within pathogens while not acting as a growth inhibitor itself. Inhibiting conjugation will be an important addition to our arsenal of strategies to combat the antibiotic resistance crisis, allowing us to extend the usefulness of antibiotics.  相似文献   
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