Background/Aims: Air trapping is associated with unfavorable outcomes in chronic obstructive pulmonary disease (COPD). The present study evaluated the association between longitudinal changes in air trapping with pulmonary function, computed tomography (CT) parameters and exacerbation. Methods: Patients enrolled in the Korean Obstructive Lung Disease (KOLD) study cohort from June 2005 to October 2015 were included. The study patients were categorized into four groups according to the change in residual volume to total lung capacity ratio (RV/TLC) over 3 years. The RV/TLC was considered abnormal when it was ≥ 40% and normal when it was < 40%. Results: A total of 279 patients were categorized into four groups: 76 in the “normal to normal” (N→N) group, 34 in the “abnormal to normal” (A→N) group, 33 in the “normal to abnormal” (N→A) group, and 136 in the “abnormal to abnormal” (A→A) group. For forced expiratory volume in 1 second and forced vital capacity (FVC), respectively, group A→N showed a large increase of 266 mL (p < 0.001) and 381 mL (p < 0.001), group N→A showed a marked decrease of 216 mL (p < 0.001) and 332 mL(p = 0.029), and group A→A showed a decrease of 16 mL (p = 0.426) and 6 mL (p = 0.011) compared to group N→N. Group A→N showed a significant decrease of –0.013 in expiratory to inspiratory ratio of the mean lung density (p < 0.001), while group A→N showed an increase of 0.005 (p < 0.001). Conclusions Patients with COPD whose RV/TLC changed from normal to abnormal showed deterioration of pulmonary function and worsening of CT parameters simultaneously

BACKGROUND: Corneal scarring or disease may lead to severe corneal opacification and consequently, severe loss of vision due to the complete loss of corneal epithelial cells. We studied the use of epithelial cell sheets differentiated from fetal cartilage-derived stem cells (FCSC) to resurface damaged cornea. METHODS: The FCSC were isolated from the femoral head of immature cartilage tissue. The ability of the FCSCs to differentiate into corneal epithelial cells was evaluated using differentiation media at 2 days and 7 days post-seeding. A sheet fabricated of FCSCs was also used for the differentiation assay. The results of the in vitro studies were evaluated by immunocytochemistry and Western blots for corneal epithelial cell markers (CK3/12 and Pax6) and limbal epithelial stem cell markers (ABCG2 and p63). To test the material in vivo, an FCSC-sheet was applied as a treatment in a chemically burned rabbit model. The healing ability was observed histologically one week after treatment. RESULTS: The in vitro experiments showed morphological changes in the FCSCs at two and seven days of culture. The differentiated cells from the FCSCs or the FCSC-sheet expressed corneal epithelial cells markers. FCSC were create cell sheet that successfully differentiated into corneal epithelial cells and had sufficient adhesion so that it could be fused to host tissue after suture to the ocular surface with silk suture. The implanted cell sheet maintained its transparency and the cells were alive a week after implantation. CONCLUSION These results suggest that carrier-free sheets fabricated of FCSCs have the potential to repair damaged corneal surfaces.

Background/Aims: Air trapping is associated with unfavorable outcomes in chronic obstructive pulmonary disease (COPD). The present study evaluated the association between longitudinal changes in air trapping with pulmonary function, computed tomography (CT) parameters and exacerbation. Methods: Patients enrolled in the Korean Obstructive Lung Disease (KOLD) study cohort from June 2005 to October 2015 were included. The study patients were categorized into four groups according to the change in residual volume to total lung capacity ratio (RV/TLC) over 3 years. The RV/TLC was considered abnormal when it was ≥ 40% and normal when it was < 40%. Results: A total of 279 patients were categorized into four groups: 76 in the “normal to normal” (N→N) group, 34 in the “abnormal to normal” (A→N) group, 33 in the “normal to abnormal” (N→A) group, and 136 in the “abnormal to abnormal” (A→A) group. For forced expiratory volume in 1 second and forced vital capacity (FVC), respectively, group A→N showed a large increase of 266 mL (p < 0.001) and 381 mL (p < 0.001), group N→A showed a marked decrease of 216 mL (p < 0.001) and 332 mL(p = 0.029), and group A→A showed a decrease of 16 mL (p = 0.426) and 6 mL (p = 0.011) compared to group N→N. Group A→N showed a significant decrease of –0.013 in expiratory to inspiratory ratio of the mean lung density (p < 0.001), while group A→N showed an increase of 0.005 (p < 0.001). Conclusions Patients with COPD whose RV/TLC changed from normal to abnormal showed deterioration of pulmonary function and worsening of CT parameters simultaneously

BACKGROUND: Corneal scarring or disease may lead to severe corneal opacification and consequently, severe loss of vision due to the complete loss of corneal epithelial cells. We studied the use of epithelial cell sheets differentiated from fetal cartilage-derived stem cells (FCSC) to resurface damaged cornea. METHODS: The FCSC were isolated from the femoral head of immature cartilage tissue. The ability of the FCSCs to differentiate into corneal epithelial cells was evaluated using differentiation media at 2 days and 7 days post-seeding. A sheet fabricated of FCSCs was also used for the differentiation assay. The results of the in vitro studies were evaluated by immunocytochemistry and Western blots for corneal epithelial cell markers (CK3/12 and Pax6) and limbal epithelial stem cell markers (ABCG2 and p63). To test the material in vivo, an FCSC-sheet was applied as a treatment in a chemically burned rabbit model. The healing ability was observed histologically one week after treatment. RESULTS: The in vitro experiments showed morphological changes in the FCSCs at two and seven days of culture. The differentiated cells from the FCSCs or the FCSC-sheet expressed corneal epithelial cells markers. FCSC were create cell sheet that successfully differentiated into corneal epithelial cells and had sufficient adhesion so that it could be fused to host tissue after suture to the ocular surface with silk suture. The implanted cell sheet maintained its transparency and the cells were alive a week after implantation. CONCLUSION These results suggest that carrier-free sheets fabricated of FCSCs have the potential to repair damaged corneal surfaces.

Background/Aims: Papillary gastric cancer (GC) is classified as differentiated adenocarcinoma, together with well-differentiated (WD) and moderately differentiated (MD) adenocarcinoma. This study evaluated the risk of lymph node metastasis (LNM) in submucosal (SM) invasive papillary GC compared with other differentiated early GC types. Methods: This retrospective study involved three tertiary hospitals and enrolled 1,798 lesions with differentiated SM invasive GC treated with curative gastrectomy between March 2001 and December 2012. All pathology slides were reviewed, and clinicopathologic findings associated with LNM, including tumor size, location, gross type, ulceration, depth and width of SM invasion, and lymphovascular invasion (LVI), were analyzed. Results: The proportion of SM papillary GC was 2.8% (n=51). SM papillary GC was associated with larger tumor size and deeper and wider SM invasion than other differentiated GC types.LNM was significantly higher in the papillary type than in the MD and WD types. LNM was found in 27.5% of SM papillary GC patients (WD: 9.0%, MD: 21.2%). LVI was the only significant risk factor for LNM in SM papillary GC. The depth or width of SM invasion was not associated with LNM in papillary GC. Lower third location or elevated gross appearance was significantly associated with LVI. Conclusions SM papillary GC had the highest LNM rate, with features different from those of other differentiated SM invasive GCs. The treatment strategy for SM papillary GC should be carefully approached, especially for lesions located in the lower third or of the elevated gross type.

BACKGROUND: Although the association of hyperuricemia with an increased risk of mortality has been demonstrated in the context of acute exacerbation of chronic obstructive pulmonary disease (COPD), the long-term outcomes of hyperuricemia have not been studied in the case of stable COPD.METHODS: We retrospectively analyzed baseline data of 240 men with stable COPD enrolled in the Korea Obstructive Lung Disease cohort. We evaluated associations between serum uric acid levels and clinical parameters, risk factors for all-cause mortality, and acute exacerbation of COPD.RESULTS: The mean age of subjects was 66.4 ± 7.7 years, and the median follow-up time was 5.9 years. We identified no significant difference in terms of lung function or laboratory findings between patients with hyperuricemia and those without. Serum uric acid level was negatively associated with systemic inflammation indicated by neutrophil–lymphocyte ratio (r = −0.211, P = 0.001). Univariate Cox regression analysis revealed hyperuricemia to not be associated with an increased risk of all-cause mortality in men with stable COPD (hazard ratio [HR], 0.580; 95% confidence interval [CI], 0.250–1.370; P = 0.213). In the multivariate Cox regression model, hyperuricemia was not an independent predictor of acute exacerbation (HR, 1.383; 95% CI, 0.977–1.959; P = 0.068).CONCLUSION: Among men with stable COPD, hyperuricemia is not an independent predictor of all-cause mortality or future acute exacerbation of COPD. These results differ from those of previous studies on patients with acute exacerbation of COPD.
Cohort Studies ; Follow-Up Studies ; Humans ; Hyperuricemia ; Inflammation ; Korea ; Lung ; Lung Diseases, Obstructive ; Male ; Mortality ; Pulmonary Disease, Chronic Obstructive ; Retrospective Studies ; Risk Factors ; Uric Acid

PURPOSE: Data are lacking on the association between the allergic rhinitis (AR) phenotype and sensitization to specific allergens or bronchial hyperresponsiveness (BHR) in children. We here investigated risk factors and comorbidities, including sensitization to specific allergens and BHR, for the AR phenotype by AR and its Impact on Asthma (ARIA) classification in a general population-based birth cohort study. METHODS: We enrolled 606 children aged 7 years from the Panel Study of Korean Children. The AR phenotype was assigned in accordance with the ARIA classification in children. Skin prick tests and Provocholine provocation test were performed. Risk factors and comorbidities for AR phenotypes were then analyzed. RESULTS: The prevalence of mild and moderate to severe AR in our study cohort was 37.2% and 8.8%, respectively. Recent use of analgesics or antipyretics and current cat ownership were associated with the risk of mild persistent AR. Sensitizations to Dermatophagoides Pteronyssinus (Der p), Japanese hop and cat were associated with moderate to severe persistent AR. Children with moderate to severe AR had a higher risk of current asthma and BHR compared to mild AR cases (adjusted odds ratio [aOR], 5.26; 95% confidence interval [CI], 1.77–15.62). Moderate to severe AR with allergic sensitization was associated with the highest risk of BHR (aOR, 11.77; 95% CI, 3.40–40.74). CONCLUSIONS: Moderate to severe-persistent AR is more closely related to respiratory comorbidities and sensitizations than mild AR. Stratifying the AR phenotype by ARIA classification may assist in disease management.
Allergens ; Analgesics ; Animals ; Antipyretics ; Asian Continental Ancestry Group ; Asthma ; Bronchial Hyperreactivity ; Cats ; Child ; Classification ; Cohort Studies ; Comorbidity ; Dermatophagoides pteronyssinus ; Disease Management ; Humans ; Methacholine Chloride ; Odds Ratio ; Ownership ; Parturition ; Phenotype ; Prevalence ; Rhinitis, Allergic ; Risk Factors ; Skin

Objective: We aimed to explore the differential impact of cigarette smoking on fracture risks in SCD and dementia. Methods: A nationwide population-based cohort study design was used. Out of all the people aged 66 (n=1,555,103) who went through the National Screening Program from 2009–2014, 968,240 participants with eligible data were included in the study. Time-to-event was calculated as the duration between the NSPTA and fracture incidence. Cox proportional-hazard regression analyses were conducted to evaluate the risk of fractures. Results: Increased risk of all [adjusted hazard ratio (aHR)=1.184; 95% confidence interval (CI)=1.184, 1.093–1.283], hip (aHR=1.518; 95% CI=1.168–4.972), vertebral (aHR=1.235; 95% CI=1.101–1.386) fractures were increased in current smokers with more than 20 or more pack years (≥20 py) of SCD group, after adjusting for all relevant confounding factors. In dementia group, however, current smokers ≥20 py were at reduced risk of hip fractures (aHR=0.249; 95% CI=0.089–0.97). Conclusion There was a disparate influence of cigarette smoking on the fracture risks in SCD and dementia group. Further studies are warranted to explicate this phenomenon, and personalized preventive measures according to one’s cognitive status are imperative, since risk factors of fractures can exert disparate influence on patients at different stage of cognitive trajectory.

Objective: Previous studies investigating association of alcohol intake and fracture risk in elderly yielded conflicting results. We first examined the association between alcohol intake and total fracture risk in elderly subjects and further analyzed whether the association varied by fracture locations. Methods: This is a nationwide population-based cohort study which included all people aged 66 (n=1,431,539) receiving the National Screening Program during 2009–2014. Time-to-event were defined as duration from study recruitment, the day they received health screening, to the occurrence of fracture. Results: Total fracture was significantly lower in mild drinkers [adjusted hazard ratio (aHR)=0.952; 95% confidence interval (95% CI) =0.931–0.973] and higher in heavy drinkers (aHR=1.246; 95% CI=1.201–1.294) than non-drinkers. Risk pattern of alcohol consumption and fracture differed according to affected bones. Similar J-shaped trends were observed for vertebra fractures, but risk of limb fracture showed a linear relationship with alcohol intake. For hip fracture, risk decrement was more pronounced in mild and moderate drinkers, and significant increment was noted only in very severe drinkers [≥60 g/day; (aHR)=1.446; 1.162–1.801]. Conclusion Light to moderate drinking generally lowered risk of fractures, but association between alcohol and fracture risk varied depending on the affected bone lesions.

Background and Objectives: The Sapien 3 (S3) valve has not been compared to the Sapien XT (SXT) valve in Korea. We compared procedural and clinical outcomes between the 2 devices. Methods: A total of 189 patients who underwent transcatheter aortic valve replacement (TAVR) with S3 (n=95) or SXT (n=94) valve was analyzed. The primary endpoint was cardiovascular mortality at 1 year. The median follow-up duration was 438 days. Results: The Society of Thoracic Surgeons score was similar between the 2 groups. The device success rate (90.4% vs. 97.9%; p=0.028) was higher in the S3 than in the SXT. The S3 showed significantly fewer cases of moderate or severe paravalvular leakage (PVL) (16.7% vs.0.0%; p=0.001) than the SXT. However, effective orifice area (EOA) (2.07±0.61 vs. 1.70±0.49 cm2 ; p<0.001) was smaller in the S3. Multivariable Cox regression analysis showed the S3 was associated with significantly fewer cardiovascular mortality at 1 year compared to the SXT (5.4% vs. 1.1%; hazard ratio, 0.031; 95% confidence interval, 0.001–0.951; p=0.047). Periprocedural complication rates, composite of disabling stroke or all-cause mortality, allcause mortality, and disabling stroke at 1 year were similar between the 2 groups. Conclusions Cardiovascular mortality was lower in the S3 group than in the SXT group over 1 year of follow-up. The reduction in PVL was attributed to the higher device success rate of TAVR with the S3 valve. However, the benefit of S3 obtained at the expense of reduced EOA should be meticulously re-evaluated in larger studies during long-term follow-up.