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BackgroundAsthma and chronic obstructive pulmonary disease (COPD) are airway diseases with similar clinical manifestations, despite differences in pathophysiology. Asthma-COPD overlap (ACO) is a condition characterized by overlapping clinical features of both diseases. There have been few reports regarding the prevalence of ACO in COPD and severe asthma cohorts. ACO is heterogeneous; patients can be classified on the basis of phenotype differences. This study was performed to analyze the prevalence of ACO in COPD and severe asthma cohorts. In addition, this study compared baseline characteristics among ACO patients according to phenotype.MethodsPatients with COPD were prospectively enrolled into the Korean COPD subgroup study (KOCOSS) cohort. Patients with severe asthma were prospectively enrolled into the Korean Severe Asthma Registry (KoSAR). ACO was defined in accordance with the updated Spanish criteria. In the COPD cohort, ACO was defined as bronchodilator response (BDR) ≥ 15% and ≥ 400 mL from baseline or blood eosinophil count (BEC) ≥ 300 cells/μL. In the severe asthma cohort, ACO was defined as age ≥ 35 years, smoking ≥ 10 pack-years, and post-bronchodilator forced expiratory volume in 1 s/forced vital capacity < 0.7. Patients with ACO were divided into four groups according to smoking history (threshold: 20 pack-years) and BEC (threshold: 300 cells/μL).ResultsThe prevalence of ACO significantly differed between the COPD and severe asthma cohorts (19.8% [365/1,839] vs. 12.5% [104/832], respectively; P < 0.001). The percentage of patients in each group was as follows: group A (light smoker with high BEC) – 9.1%; group B (light smoker with low BEC) – 3.7%; group C (moderate to heavy smoker with high BEC) – 73.8%; and group D (moderate to heavy smoker with low BEC) – 13.4%. Moderate to heavy smoker with high BEC group was oldest, and showed weak BDR response. Age, sex, BDR, comorbidities, and medications significantly differed among the four groups.ConclusionThe prevalence of ACO differed between COPD and severe asthma cohorts. ACO patients can be classified into four phenotype groups, such that each phenotype exhibits distinct characteristics.  相似文献   
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Background: Assessment the depth of dexmedetomidine sedation using electroencephalographic (EEG) features can improve the quality of procedural sedation. Previous volunteer studies of dexmedetomidine-induced EEG changes need to be validated, and changes in bicoherence spectra during dexmedetomidine sedation has not been revealed yet. We aimed to investigate the dexmedetomidine-induced EEG change using power spectral and bicoherence analyses in the clinical setting.Patients and Methods: Thirty-six patients undergoing orthopedic surgery under spinal anesthesia were enrolled in this study. Dexmedetomidine sedation was conducted by the stepwise increase in target effect site concentration (Ce) while assessing sedation levels. Bispectral index (BIS) and frontal electroencephalography were recorded continuously, and the performance of BIS and changes in power and bicoherence spectra were analyzed with the data from the F3 electrode.Results: The prediction probability values for detecting different sedation levels were 0.847, 0.841, and 0.844 in BIS, 95% spectral edge frequency, and dexmedetomidine Ce, respectively. As the depth of sedation increased, δ power increased, but high β and γ power decreased significantly (P <0.001). α and spindle power increased significantly under light and moderate sedation (P <0.001 in light vs baseline and deep sedation; P = 0.002 and P <0.001 in moderate sedation vs baseline and deep sedation, respectively). The bicoherence peaks of the δ and α-spindle regions along the diagonal line of the bicoherence matrix emerged during moderate and deep sedation. Peak bicoherence in the δ area showed sedation-dependent increases (29.93%±7.38%, 36.72%±9.70%, 44.88%±12.90%; light, moderate, and deep sedation; P = 0.008 and P <0.001 in light sedation vs moderate and deep sedation, respectively; P = 0.007 in moderate sedation vs deep sedation), whereas peak bicoherence in the α-spindle area did not change (22.92%±4.90%, 24.72%±4.96%, and 26.96%±8.42%, respectively; P=0.053).Conclusions: The increase of δ power and the decrease of high-frequency power were associated with the gradual deepening of dexmedetomidine sedation. The δ bicoherence peak increased with increasing sedation level and can serve as an indicator reflecting dexmedetomidine sedation levels.  相似文献   
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This study examined the effects of the kaempferol derivatives extracted from Zingiber zerumbet on the accumulation and efflux of [(3)H]-daunomycin (DNM) in P-glycoprotein (P-gp) overexpressing multidrug resistant (MDR) human breast cancer cells, MCF-7/ADR. Of six kaempferol derivatives extracted from Z. zerumbet, kaempferol-3-O-methyl ether (1) and kaempferol-3,4'-O-dimethyl ether (2) showed a potent P-gp inhibitory effect as great as verapamil, a well-known P-gp inhibitor. The P-gp inhibitory activity of these two compounds was through a 3-fold increase of the level of [(3)H]-DNM accumulation and a decrease of P-gp-mediated efflux. These results suggest that the kaempferol derivative components of Z. zerumbet can be used as a scaffold for developing agents that reverse P-gp-mediated MDR in human cancer chemotherapy.  相似文献   
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This meta‐analysis aimed to assess the weight loss effects of circuit training interventions in adults. A computerized search was conducted using the Cochrane Central Register of Controlled Trials, PubMed, and EMBASE online databases. The analysis was restricted to randomized controlled trials that evaluated the effects of circuit training interventions on body weight and body mass index in adults aged 18 years or older. Meta‐analyses were conducted using the random‐effect model to estimate the weighted mean difference (WMD) with 95% confidence interval (CI). Nine randomized controlled trials (837 participants) were included. Significant intervention effects were identified for body weight (WMD = ?3.81 kg, 95% CI ?5.60 to ?2.02) and body mass index (WMD = ?1.77 kg/m2, 95% CI ?2.49 to ?1.04). Subgroup analysis by body mass index status showed that the intervention effect was significant only in participants with obesity or overweight (obesity: WMD = ?5.15 kg, 95% CI ?8.81 to ?1.50 and overweight: WMD = ?3.89 kg, 95% CI ?7.00 to ?0.77, respectively) but not in those with normal weight. Current evidence suggests that circuit training effectively reduces body weight and body mass index in adults with overweight and obesity.  相似文献   
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