Background: Respiratory infections play a major role in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). This study assessed the prevalence of bacterial and viral pathogens and their clinical impact on patients with AECOPD. Methods: This retrospective study included 1,186 patients diagnosed with AECOPD at 28 hospitals in South Korea between 2015 and 2018. We evaluated the identification rates of pathogens, basic patient characteristics, clinical features, and the factors associated with infections by potentially drug-resistant (PDR) pathogens using various microbiological tests. Results: Bacteria, viruses, and both were detected in 262 (22.1%), 265 (22.5%), and 129 (10.9%) of patients, respectively. The most common pathogens included Pseudomonas aeruginosa (17.8%), Mycoplasma pneumoniae (11.2%), Streptococcus pneumoniae (9.0%), influenza A virus (19.0%), rhinovirus (15.8%), and respiratory syncytial virus (6.4%). Notably, a history of pulmonary tuberculosis (odds ratio [OR], 1.66; p=0.046), bronchiectasis (OR, 1.99; p=0.032), and the use of a triple inhaler regimen within the past 6 months (OR, 2.04; p=0.005) were identified as significant factors associated with infection by PDR pathogens. Moreover, patients infected with PDR pathogens exhibited extended hospital stays (15.9 days vs. 12.4 days, p=0.018) and higher intensive care unit admission rates (15.9% vs. 9.5%, p=0.030). Conclusion This study demonstrates that a variety of pathogens are involved in episodes of AECOPD. Nevertheless, additional research is required to confirm their role in the onset and progression of AECOPD.

BACKGROUND/OBJECTIVES: Green Citrus junos (yuja) peel extract has higher naringin and hesperidin contents and antioxidant activity than yellow yuja peel extract, but its anti-obesity effects are unclear. This study examined the anti-obesity properties of green yuja peel ethanol extract (GYE) in 3T3-L1 cells and high-fat diet (HFD)-induced obese mice.MATERIALS/METHODS: The effects of GYE on adipocyte differentiation were assessed by measuring Oil red O staining, mRNA and protein expression. The beneficial effects of GYE on HFD-induced obese mice were evaluated using the body weight, body composition, visceral fat size, and biochemical analysis. RESULTS: GYE inhibited adipocyte differentiation and lipid accumulation compared to the control cells, as evidenced by Oil red O staining and the triglyceride level, respectively.GYE down-regulated the adipogenic genes CCAAT/enhancer binding protein α (C/EBPα) and peroxisome proliferator-activated receptor γ (PPARγ), and lipogenic gene diacylglycerol O-acyltransferase 2 (DGAT2). GYE at 100 μg/mL downregulated the phosphorylation levels of phosphoinositide 3-kinase (PI3K) and protein kinase B (Akt), and their downstream targets PPARγ and sterol regulatory element-binding protein-1 (SREBP-1c) compared to the control group. In obese mice, GYE (100 mg/kg/day) reduced the body weight, body weight gain, and serum lipid level compared to the control group. Analysis using dual-energy X-ray absorptiometry showed that GYE decreased the fat percentage, fat in tissue, and abdominal circumference, while it increased the lean percentage compared to control group.Furthermore, GYE significantly reduced the visceral fat weight and size compared to the control group. CONCLUSION GYE suppressed adipocyte differentiation by inhibiting the PI3K-Akt pathway in vitro and reduced the body fat mass and visceral adiposity in HFD-induced obese mice.These findings suggest that GYE is a viable natural option for combating obesity.

Purpose: Smoking may have a protective role in developing ulcerative colitis (UC) but have the opposite effect on Crohn’s disease (CD). This study aimed to determine the risk of developing inflammatory bowel disease (IBD) according to smoking status and onset age of smoking. Materials and Methods: We collected data on the smoking experiences of participants aged 20–39 years who underwent biannual examinations provided by the Korean National Health Screening Program from 2009 to 2012. IBD diagnosis was identified using the National Health Insurance Service. The risk of IBD according to smoking status and onset age of smoking was analyzed after adjusting for major clinical variables. Results: During a median 10.59-year follow-up, the risk of UC in ex-smokers was significantly higher than that in non-smokers, and the earlier ex-smokers started smoking, the higher risk of UC [ex-smokers whose onset age of smoking was <20 years, adjusted hazard ratio (aHR) 1.928, 95% confidence interval (CI)=1.649–2.255; 20–24 years, aHR 1.728, 95% CI=1.541–1.939; 25–29 years, aHR 1.676, 95% CI=1.489–1.887; ≥30 years, aHR 1.226, 95% CI=1.010–1.486]. The risk of UC was significantly lower in current smokers whose onset age of smoking was 25–29 years than in non-smokers (aHR 0.825, 95% CI=0.709–0.959). The risk of CD did not differ according to smoking status and onset age of smoking. Conclusion Ex-smokers who started smoking at a young age have a high risk of UC, even after adjusting for the smoking amount.

Background: This study established sex-specific reference intervals (RIs) for hematological parameters, including the monocyte distribution width (MDW), in Korean adults and assessed the need for separate RIs according to sex in older adults. Methods: Hematological parameters were measured using a DxH 900 hematology analyzer (Beckman Coulter, USA) on 328 peripheral blood samples from 124 men and 204 women aged 19–93 years. Results: The RIs for white blood cells, red blood cells (RBCs), Hb, Hct, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, monocyte percentage, and neutrophil, eosinophil, lympho­cyte, and monocyte counts differed significantly by sex (P<0.05). Mean corpuscular volume was significantly positively associated with age, whereas RBC and platelet counts were significantly negatively correlated with age in both men and women. Age-based analysis revealed significant shifts in the RBC parameters beginning at 60 years of age in men and 70 years of age in women. The MDW did not show significant differences according to sex or age. Conclusions This study supports the use of sex-specific RIs and highlights the importance of considering age when interpreting results regarding hematological parameters in clinical practice.

Background: This study established sex-specific reference intervals (RIs) for hematological parameters, including the monocyte distribution width (MDW), in Korean adults and assessed the need for separate RIs according to sex in older adults. Methods: Hematological parameters were measured using a DxH 900 hematology analyzer (Beckman Coulter, USA) on 328 peripheral blood samples from 124 men and 204 women aged 19–93 years. Results: The RIs for white blood cells, red blood cells (RBCs), Hb, Hct, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, monocyte percentage, and neutrophil, eosinophil, lympho­cyte, and monocyte counts differed significantly by sex (P<0.05). Mean corpuscular volume was significantly positively associated with age, whereas RBC and platelet counts were significantly negatively correlated with age in both men and women. Age-based analysis revealed significant shifts in the RBC parameters beginning at 60 years of age in men and 70 years of age in women. The MDW did not show significant differences according to sex or age. Conclusions This study supports the use of sex-specific RIs and highlights the importance of considering age when interpreting results regarding hematological parameters in clinical practice.

Background: Respiratory infections play a major role in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). This study assessed the prevalence of bacterial and viral pathogens and their clinical impact on patients with AECOPD. Methods: This retrospective study included 1,186 patients diagnosed with AECOPD at 28 hospitals in South Korea between 2015 and 2018. We evaluated the identification rates of pathogens, basic patient characteristics, clinical features, and the factors associated with infections by potentially drug-resistant (PDR) pathogens using various microbiological tests. Results: Bacteria, viruses, and both were detected in 262 (22.1%), 265 (22.5%), and 129 (10.9%) of patients, respectively. The most common pathogens included Pseudomonas aeruginosa (17.8%), Mycoplasma pneumoniae (11.2%), Streptococcus pneumoniae (9.0%), influenza A virus (19.0%), rhinovirus (15.8%), and respiratory syncytial virus (6.4%). Notably, a history of pulmonary tuberculosis (odds ratio [OR], 1.66; p=0.046), bronchiectasis (OR, 1.99; p=0.032), and the use of a triple inhaler regimen within the past 6 months (OR, 2.04; p=0.005) were identified as significant factors associated with infection by PDR pathogens. Moreover, patients infected with PDR pathogens exhibited extended hospital stays (15.9 days vs. 12.4 days, p=0.018) and higher intensive care unit admission rates (15.9% vs. 9.5%, p=0.030). Conclusion This study demonstrates that a variety of pathogens are involved in episodes of AECOPD. Nevertheless, additional research is required to confirm their role in the onset and progression of AECOPD.

Purpose: Smoking may have a protective role in developing ulcerative colitis (UC) but have the opposite effect on Crohn’s disease (CD). This study aimed to determine the risk of developing inflammatory bowel disease (IBD) according to smoking status and onset age of smoking. Materials and Methods: We collected data on the smoking experiences of participants aged 20–39 years who underwent biannual examinations provided by the Korean National Health Screening Program from 2009 to 2012. IBD diagnosis was identified using the National Health Insurance Service. The risk of IBD according to smoking status and onset age of smoking was analyzed after adjusting for major clinical variables. Results: During a median 10.59-year follow-up, the risk of UC in ex-smokers was significantly higher than that in non-smokers, and the earlier ex-smokers started smoking, the higher risk of UC [ex-smokers whose onset age of smoking was <20 years, adjusted hazard ratio (aHR) 1.928, 95% confidence interval (CI)=1.649–2.255; 20–24 years, aHR 1.728, 95% CI=1.541–1.939; 25–29 years, aHR 1.676, 95% CI=1.489–1.887; ≥30 years, aHR 1.226, 95% CI=1.010–1.486]. The risk of UC was significantly lower in current smokers whose onset age of smoking was 25–29 years than in non-smokers (aHR 0.825, 95% CI=0.709–0.959). The risk of CD did not differ according to smoking status and onset age of smoking. Conclusion Ex-smokers who started smoking at a young age have a high risk of UC, even after adjusting for the smoking amount.

Objective: This study aims to objectively evaluate turning gait parameters in Parkinson’s disease (PD) patients using 2D-RGB video-based analysis and explore their relationships with imbalance. Methods: We prospectively enrolled PD patients for clinical assessment, balance analysis and gait with 180º turning. Spatiotemporal gait parameters during turning were derived using video-based analysis and correlated with modified Hoehn and Yahr (mHY) stages and center of pressure (COP) oscillations. Results: A total of 64 PD patients were enrolled. The PD patients with higher mHY stages (≥2.5) had significantly longer turning times, greater numbers of steps, wider step bases and less variability in step length during turns. COP oscillations were positively correlated with the mean turning time on both the anterior-posterior and right-left axes. Conclusion Spatiotemporal gait parameter during turning, derived from video-based gait analysis, may represent apromising biomarker for monitoring postural instability in PD patients.

Background: and Purpose Previous research on patients with acute ischemic stroke (AIS) has shown a 0.5% incidence of major gastrointestinal bleeding (GIB) requiring blood transfusion during hospitalization. The existing literature has insufficiently explored the long-term incidence in this population despite the decremental impact of GIB on stroke outcomes. Methods: We analyzed the data from a cohort of patients with AIS admitted to 14 hospitals as part of a nationwide multicenter prospective stroke registry between 2011 and 2013. These patients were followed up for up to 6 years. The occurrence of major GIB events, defined as GIB necessitating at least two units of blood transfusion, was tracked using the National Health Insurance Service claims data. Results: Among 10,818 patients with AIS (male, 59%; mean age, 68±13 years), 947 (8.8%) experienced 1,224 episodes of major GIB over a median follow-up duration of 3.1 years. Remarkably, 20% of 947 patients experienced multiple episodes of major GIB. The incidence peaked in the first month after AIS, reaching 19.2 per 100 person-years, and gradually decreased to approximately one-sixth of this rate by the 2nd year with subsequent stabilization. Multivariable analysis identified the following predictors of major GIB: anemia, estimated glomerular filtration rate <60 mL/min/1.73 m2 , and a 3-month modified Rankin Scale score of ≥4. Conclusion Patients with AIS are susceptible to major GIB, particularly in the first month after the onset of AIS, with the risk decreasing thereafter. Implementing preventive strategies may be important, especially for patients with anemia and impaired renal function at stroke onset and those with a disabling stroke.

Background and Objectives: Cigarette smoking is a major risk factor for atherosclerosis.Nicotine, a crucial constituent of tobacco, contributes to atherosclerosis development and progression. However, evidence of the association between nicotine and neointima formation is limited. We aimed to evaluate whether nicotine enhances neointimal hyperplasia in the native epicardial coronary arteries of pigs after percutaneous coronary intervention (PCI) with drug-eluting stents (DES). Methods: After coronary angiography (CAG) and quantitative coronary angiography (QCA), we implanted 20 DES into 20 pigs allocated to 2 groups: no-nicotine (n=10) and nicotine (n=10) groups. Post-PCI CAG and QCA were performed immediately. Follow-up CAG, QCA, optical coherence tomography (OCT), and histopathological analyses were performed 2 months post-PCI. Results: Despite intergroup similarities in the baseline QCA findings, OCT analysis showed that the nicotine group had a smaller mean stent and lumen areas, a larger mean neointimal area, greater percent area stenosis, and higher peri-strut fibrin and inflammation scores than the no-nicotine group. In immunofluorescence analysis, the nicotine group displayed higher expression of CD68 and α-smooth muscle actin but lower CD31 expression than the no-nicotine group. Conclusions Nicotine inhibited re-endothelialization and promoted inflammation and NIH after PCI with DES in a porcine model.