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941.
BackgroundVancomycin is the treatment of choice for serious methicillin-resistant Staphylococcus aureus (MRSA) infections. Current guidelines recommend giving an initial loading dose (LD) of 25–30 mg/kg to rapidly increase the serum concentration. However, high-quality evidence for the clinical benefit of LD is lacking. Herein, we aim to examine the association between vancomycin LD and clinical outcome.MethodsA retrospective cohort study was conducted on adult patients treated for MRSA pneumonia with vancomycin in medical intensive care units from April 2016 to August 2018. MRSA pneumonia was defined by the Centers for Disease Control and National Healthcare Safety Network definition. The primary outcome was the clinical cure of pneumonia. Secondary outcome measures included time to pharmacokinetic (PK) target attainment, microbiological cure, acute kidney injury, and all-cause mortality.ResultsA total of 81 patients were included; of these 22 (27.2%) received LD. The mean initial dose was significantly higher in the LD group. Clinical cure was similar in both groups (68.2% vs. 66.1% in the LD and non-LD groups, respectively; P=0.860). No significant difference was observed in the microbiological cure, all-cause mortality, and incidence of acute kidney injury. Furthermore, no difference was observed in terms of time to PK target attainment (69.2 vs. 63.4 h in the LD and non-LD groups, respectively; P=0.624). Vancomycin minimum inhibitory concentration of <2 mg/L was identified as an independent predictive factor for clinical cure in multivariable analysis, whereas vancomycin LD was not.ConclusionsInitial LD is not associated with better clinical outcome or rapid pharmacological target attainment in critically ill patients with MRSA pneumonia. Further studies are warranted to provide better evidence for this widely recommended practice.  相似文献   
942.
BackgroundForced vital capacity (FVC) has been suggested to be a good biomarker for decreased exercise performance in patients with chronic obstructive pulmonary disease (COPD). However, as FVC is highly correlated with forced expiratory volume in 1 second (FEV1), the relationship between FVC and exercise capacity should be assessed within the category of FEV1, i.e., COPD severity. However, this was not considered in previous studies. Thus, limited data are available on the association between reduced FVC and exercise capacity measured by 6-min walk distance (6MWD) based on COPD severity.MethodsWe performed a cross-sectional study using data from the Korean COPD Subgroup Study (KOCOSS) cohort. We evaluated 1,386 patients with moderate (n=895) and severe-to-very severe (n=491) COPD. Reduced FVC was defined as FVC <80% predicted and short 6MWD as <350 m. Multivariable logistic regression was used to evaluate the association between reduced FVC and short 6MWD.ResultsThere were no significant differences in respiratory symptoms and quality of life between the patients with reduced FVC and those with preserved FVC. However, patients with reduced FVC had shorter 6MWD (30.5 cm in moderate and 34.5 cm in severe-to-very severe COPD) and higher BODE index scores than those with preserved FVC. The cubic spline model revealed 6MWD peaked around 93% predicted of FVC in moderate COPD, whereas FVC showed a positive association with 6MWD in severe-to-very severe COPD. Multivariable analyses showed that reduced FVC was significantly associated with short 6MWD in both moderate [adjusted odds ratio (aOR) =1.44, 95% confidence interval (CI): 1.03–2.02] and severe-to-very severe (adjusted OR =1.55, 95% CI: 1.01–2.40) COPD.ConclusionsReduced FVC was significantly associated with shorter 6MWD in moderate-to-very severe COPD patients, suggesting that reduced FVC might be reflective of 6MWD-measured exercise capacity in moderate-to-very severe COPD.  相似文献   
943.
BackgroundChronic obstructive pulmonary disease (COPD) has variable subtypes involving mixture of large airway inflammation, small airway disease, and emphysema. This study evaluated the relationship between visually assessed computed tomography (CT) subtypes and clinical/imaging characteristics.MethodsIn total, 452 participants were enrolled in this study between 2012 and 2017. Seven subtypes were defined by visual evaluation of CT images using Fleischner Society classification: normal, paraseptal emphysema (PSE), bronchial disease, and centrilobular emphysema (trace, mild, moderate and confluent/advanced destructive). The differences in several variables, including clinical, laboratory, spirometric, and quantitative CT features among CT-based visual subtypes, were compared using the chi-square tests and one-way analysis of variance.ResultsSubjects who had PSE had better forced expiratory volume in 1 second (FEV1) (P=0.03) percentage and higher lung density (P<0.05) than those with moderate to confluent/advanced destructive centrilobular emphysema. As the visual grade of centrilobular emphysema worsened, pulmonary function declined and modified Medical Research Council, COPD assessment test (CAT) score, and quantitative assessment (emphysema index and air trapping) increased. The bronchial subtype was associated with higher body mass index (BMI), better lung function and higher lung density. Participants with trace emphysema showed a rapid increase in functional small airway diseaseConclusionsClassifying subtypes using visual CT imaging features can reflect heterogeneity and pathological processes of COPD.  相似文献   
944.
Journal of Interventional Cardiac Electrophysiology - Substrate mapping has highlighted the importance of targeting diastolic conduction channels and late potentials during ventricular tachycardia...  相似文献   
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947.
BackgroundThe BALAD score and BALAD-2 class derived from bilirubin, albumin, AFP, AFP-L3, and des-gamma-carboxyprothrombin (DCP) are effective in predicting mortality in HCC, but have not been validated in North America.Methods148 HCC patients from 2000 to 2015 who had all five biomarkers tested at diagnosis were included. Hazard ratios (HR) were calculated.Results75 patients died during a median follow-up of 21.9 months. 1-and 3-year survival rates were 70.8% and 47.6%. 114 (77%) had cirrhosis. The HR (95%CI) for death were 1.24 (0.42–3.67), 1.79 (0.61–5.26), 2.83 (0.95–8.38), and 7.19 (2.26–22.91) for BALAD scores 1, 2, 3, and 4 vs. BALAD 0. The HR (95%CI) for death were 1.25 (0.65–2.40), 1.75 (0.94–3.23), and 6.20 (3.29–11.68) for BALAD-2 classes 2, 3, and 4 vs. BALAD-2 class 1. A multivariate model incorporating maximal tumor diameter, tumor number, neutrophil-lymphocyte ratio, and BALAD had HR of 1.43 (1.14–1.81) per increase of 1 BALAD score. A similar model with BALAD-2 had HR of 1.50 (1.18–1.90) per increase of 1 BALAD-2 class.ConclusionBALAD models at diagnosis can predict the survival of HCC patients in North America. AFP, AFP-L3, and DCP reflect tumor progression and metastasis of HCC and distinguish the BALAD model from other predictive models.  相似文献   
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950.
Although coffee is known to have antioxidant, anti-inflammatory, and antitumor properties, there have been few reports about the effect and mechanism of coffee compounds in colorectal cancer. Heat shock proteins (HSPs) are molecular chaperones that prevent cell death. Their expression is significantly elevated in many tumors and is accompanied by increased cell proliferation, metastasis and poor response to chemotherapy. In this study, we investigated the cytotoxicity of four bioactive compounds in coffee, namely, caffeine, caffeic acid, chlorogenic acid, and kahweol, in HT-29 human colon adenocarcinoma cells. Only kahweol showed significant cytotoxicity. Specifically, kahweol increased the expression of caspase-3, a pro-apoptotic factor, and decreased the expression of anti-apoptotic factors, such as Bcl-2 and phosphorylated Akt. In addition, kahweol significantly attenuated the expression of HSP70. Inhibition of HSP70 activity with triptolide increased kahweol-induced cytotoxicity. In contrast, overexpression of HSP70 significantly reduced kahweol-induced cell death. Taken together, these results demonstrate that kahweol inhibits colorectal tumor cell growth by promoting apoptosis and suppressing HSP70 expression.  相似文献   
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