Chronic Rejection after Lung Transplantation

A new classification system for chronic rejection in lung transplantation was recently proposed. Chronic lung allograft dysfunction (CLAD) is regarded as chronic rejection after excluding other causes of allograft dysfunction. CLAD is divided into obstructive CLAD (bronchiolitis obliterans syndrome) and restrictive CLAD (restrictive allograft syndrome). In this review, we will review the latest concepts and current controversies regarding the new CLAD terminology, diagnostic approach, risk factors and possible treatment options.ope

기후변화가 날씨기반형 관광에 미치는 영향: 한국의 야외물놀이 활동 수요와 스키장 운영을 중심으로

학위논문 (박사)-- 서울대학교 환경대학원 협동과정 조경학, 2017. 8. 이동근.from around 90 days at present to around 80 days based on RCP 2.0, around 90 days based on RCP 4.5, around 50 days based on RCP 6.0, and 10 days based on RCP 8.5 in the areas where the average temperature of the ski season is above 0 °C. In addition, it is also estimated that in the 2090s, 16 of 17 ski resorts can survive based on RCP 2.6 and RCP 4.5, 13 ski resorts can survive based on RCP 6.0, and none of the resorts can survive based on RCP 8.5, according to the 100-days rule. The results of this study show that there will be major changes in weather-based tourism due to climate change. These changes include the expansion of season for summer weather-based tourism activities, including outdoor water activities, and a reduction of season for winter weather-based tourism, including activities such as skiing. In terms of tourism demand, tourists can easily adapt to changing environments due to climate change though the substitution of activities, seasons, and destinations. However, when it comes to tourism operation, operators, who already invested massive budgets into the development of tourist destinations, will experience difficulties in management due to the deterioration of destinations and the loss of tourists due to climate change. Thus, managerial strategies that helps operators flexibly respond to climate change are required. This study is meaningful in that it suggests landscapes which will be impacted by climate change within the tourism industry, and takes into consideration future weather-related changes, which have not been studied before in South Korea. To predict more detailed changes and suggest more meaningful countermeasures, future studies that focus on a specific type of tourism industry and a more specific location are required.The impact of climate change on the tourism industry is expected to be significant. This is especially true in the case of tourism that requires specific weather conditions to function. It is possible that such forms of tourism will experience radical changes to meet demand and operational difficulties resulting from climate change. Despite this, the academic field of tourism has shown climate change only lukewarm interest. One reason for this attitude might be the fact that the impact of climate change is invisible and long-term, and so at odds with the interests of the tourism industry, which focuses primarily on visible and short-term aspects of business. However, as the seriousness of climate change and its impact becomes more apparent, it is important for researchers to investigate the ways in which it will affect the tourism industry and plan effective countermeasures. The purpose of this study is to predict changes in weather-based tourism due to climate change and offer meaningful implications that the tourism industry can refer to when preparing to address climate change. This study employs two practical analyses. The first analysis focuses on tourism demandit analyzes the impact of climate change on the demand for outdoor water activities. The second analysis is focused on tourism supplyit analyzes the impact of climate change on the operation of ski slopes. For the impact analysis on outdoor water activities, 9 public outdoor swimming pools in 3 megacities, Seoul, Daegu, and Busan, were selected as study sites. To determine the preferred weather conditions for outdoor water activities, the best-fit lines of scatterplots of the Z-score of the number of visitors to each swimming pool and the corresponding temperatures were found. The ranges of the temperature, when the best-fit lines increase, are set as preferred weather conditions for outdoor water activities. To predict changes in the preferred season for outdoor water activities, future weather data for the 2030s, 2060s, and 2090s from RCP (Representative Concentration Pathways) scenarios are adapted to the range of temperature for preferred weather conditions. In terms of the analysis of the impact of climate change on the operation of ski slopes, all 17 ski resorts in South Korea were selected as study sites. To determine the weather and managerial conditions for the operation of ski slopes, interviews with operators and a review of past weather and operational conditions were conducted. By doing this, the conditions for artificial snowmaking, slope open, and slope close were found. To project future changes in the season of operation for ski slopes, future weather data for the 2030s, 2060s, and 2090s from RCP scenarios were adapted to the conditions of snowmaking, slope open, and slope close. In addition, the sustainability of ski slopes is also examined using the 100-days rule, which is the minimum required duration of the operation of ski resorts. The study found that, when it comes to the demand for outdoor water activities, the preferred weather conditions are found at: 24.27 °C to 35.91°C in Seoul, 25.79 °C to 35.30 °C in Daegu, and 26.91 °C to 34.08 °C in Busan. By applying the future weather data to these conditions, it is estimated that the preferred season for outdoor water activity will gradually shift from June to September to May to June and September to October due to extremely hot weather of July and August. The number of days of preferred weather for outdoor water activities will increase from: 126 days at present to 135 days in the 2090s based on RCP 2.6, 149 days based on RCP 4.5, 145 days based on RCP 6.0, and 138 days based on RCP 8.5 in Seoul136 days at present to 136 days in the 2090s based on RCP 2.6, 147 days based on RCPs 4.5 and 6.0, and 143 days based on RCP 8.5 in Daegu94 days at present to 109 days in the 2090s based on RCP 2.6, 123 days based on RCP 4.5, 127 days based on RCP 6.0, and 136 days based on RCP 8.5 in Busan. If the duration of the non-preferred weather season during July and August due to extreme hot weather is included, the number of days of the preferred season for outdoor water activities is estimated to reach six months in the 2090s. In terms of the operation of ski slopes, the preferred conditions for operation were found. Artificial snowmaking begins when the temperature reaches -2 °C, the slope is opened 9 days after artificial snowmaking starts, and the slope is closed when the temperature reaches 0 °C. By applying future weather data to these conditions, it is estimated that the ski season will decrease in the future as follows: from around 130 days at present to around 120 days based on RCP 2.0 and RCP 6.0, around 130 days based on RCP 4.5, and 90 days based on RCP 8.5 in the areas where the average temperature of the ski season is below -2 °Cfrom around 120 days at present to around 120 days based on RCP 2.0 and 4.5, around 100-days based on RCP 6.0, and 60 days based on RCP 8.5 in the areas where the average temperature of the ski season is below 0 °CI. INTRODUCTION 1 1. Purpose of the study 1 2. Scope of the study 5 3. Research questions and outline 7 II. LITERATURE REVIEW 10 1. Tourism, weather, and climate 10 2. Climate change trend and its projection 12 3. Impact of climate change on tourism 15 4. Previous studies estimating the impact of climate change on tourism 19 4.1. The impact on the demand for outdoor water activities 19 4.2. The impact on the operation of ski slopes 25 III. ANALYTICAL DESIGN 31 1. The analysis of the impact of climate change on the demand for outdoor water activities 31 1.1. Study sites 32 1.2. Data 36 1.3. Methods 38 2. The analysis of the impact of climate change on the operation of ski slopes 39 2.1. Study sites 40 2.2. Data 43 2.3. Methods 45  IV. RESULTS 47 1. The impact of climate change on the demand for outdoor water activities 47 1.1. Weather conditions for the demand for outdoor water activities 47 1.2. Projected changes in the demand for outdoor water activities 53 2. The impacts of climate change on the operation of ski slopes 60 2.1. Weather conditions for the operation of ski slopes 60 2.2. Projected changes in the operation of ski slopes 65 3. Comparison of results with previous studies 72 3.1. The impact of climate change on the demand for outdoor water activities 72 3.2. The impact of climate change on the operation of ski slopes 73 V. DISCUSSION AND CONCLUSION 77 1. Discussion 77 2. Conclusion 89 REFERENCES 93Docto

Role of retinol intake in nutritional status and metabolic syndrome in the Korean Genomic Rural Cohort

의학과/석사[한글]연구배경: 대사증후군은 제2형 당뇨병 및 심혈관 질환과 연관되어 있고 세계적으로 그 유병률이 증가 추세에 있으나 대사증후군에서 영양 및 식사의 역할은 아직 논란이 많다. 저자들은 한국 지역사회 유전체 코호트에 참여한 남성을 대상으로 영양 및 식사패턴과 대사증후군과의 연관성을 규명하고자 하였다. 방법: 2006년 한국 지역사회 유전체 코호트 중 원주, 평창, 강릉, 나주, 금산에 거주하는 40세 이상 70세 이하의 남자 4089명을 대상으로 하였다. 이 중 식사패턴에 영향을 줄 수 있는 항고혈압약제, 혈당강하제, 고지혈증약제 처방을 받고 있는 환자를 제외한 총 2983명이 참여하였다. 이들은 식품섭취빈도조사지를 비롯한 설문을 통하여 생활습관, 의학적 기왕력 및 식사력을 제공하였으며 신장, 체중, 혈압 및 허리-엉덩이 둘레의 비 등의 신체계측과 공복 및 식후 정맥채혈을 시행하였다. 대사증후군의 진단기준으로는 NCEP-ATP III 의 기준을 보완하여 이용하였다. 결과: 대사증후군이 있는 군에서 레티놀의 섭취량이 낮았다. 또한 각 영양소를 4분위수로 나눈 후 레티놀의 섭취가 증가할수록 대사증후군의 비교위험률은 감소하였다[2nd quartile OR:0.85(95% CI: 0.67-1.08), 3rd quartile OR: 0.85(95% CI: 0.66-1.09), 4th quartile OR: 0.64 (95% CI: 0.48-0.84)]. 레티놀의 섭취가 많은 군에서 대사증후군의 구성요소 중 수축기 혈압과 혈중 중성지방의 수치가 의미있게 감소하였다. 또한 레티놀의 섭취량은 비만도와 당화혈색소, LDL콜레스테롤, 식후혈당, 식후인슐린 및 수축기혈압과 음의 상관관계를 나타내었고 HDL콜레스테롤과는 양의 상관관계를 보였다. 결론: 한국인 남성에서 레티놀 섭취는 대사증후군의 각 요소들과 상관관계를 보이고 특히 레티놀의 섭취가 많은 그룹에서 수축기혈압과 중성지방이 의미있게 감소함을 알 수 있었다. 이는 충분한 레티놀의 섭취는 대사증후군의 유병률을 감소시킬 수 있음을 시사한다. 따라서 이에 대한 대규모 임상 연구가 필요할 것으로 생각된다 [영문]Background: Numerous dietary factors are related to the development of metabolic syndrome(MS). Several studies suggest that antioxidant nutrients may play a protective role in this complex disorder. The goal of the present study was to characterize the relationship between retinol intake and the prevalence of metabolic syndrome in a defined population sample.Methods: This cross-sectional study was conducted in a sample of 2983 men drawn from the Korean Genomic Rural Cohort Study. Dietary intake, including retinol intake, was assessed using a semiquantitative food frequency questionnaire. We evaluated the prevalence and odds ratios of metabolic syndrome by quartile of retinol intake. Results: Participants with metabolic syndrome reported significantly lower retinol intake than normal subjects. The prevalence of metabolic syndrome and the adjusted odds ratio were both decreased in the highest quartile of retinol intake [OR: 0.64 (95% CI, 0.483-0.847)] compared with the lowest quartile. Participants in the highest quartile also had higher body mass indexes (BMI), and waist and hip circumferences, but lower systolic blood pressures and serum triglyceride levels than those in the lowest quartile. Retinol intake showed significant negative correlations with each metabolic component except HDL cholesterol.Conclusion: Our analysis revealed an inverse association between retinol consumption and the prevalence of metabolic syndrome in a large sample of Korean men. In this study, systolic blood pressure and serum triglycerides were the main risk factors associated with retinol intake.ope

Clinical Features, Diagnosis, Management, and Outcomes of Idiopathic Pulmonary Fibrosis in Korea: Analysis of the Korea IPF Cohort (KICO) Registry

Background: The Korea Interstitial Lung Disease Study Group has made a new nationwide idiopathic pulmonary fibrosis (IPF) registry because the routine clinical practice has changed due to new guidelines and newly developed antifibrotic agents in the recent decade. The aim of this study was to describe recent clinical characteristics of Korean IPF patients. Methods: Both newly diagnosed and following IPF patients diagnosed after the previous registry in 2008 were enrolled. Survival analysis was only conducted for patients diagnosed with IPF after 2016 because antifibrotic agents started to be covered by medical insurance of Korea in October 2015. Results: A total of 2,139 patients were analyzed. Their mean age at diagnosis was 67.4±9.3 years. Of these patients, 76.1% were males, 71.0% were ever-smokers, 14.4% were asymptomatic at the time of diagnosis, and 56.9% were at gender-agephysiology stage I. Occupational toxic material exposure was reported in 534 patients. The mean forced vital capacity was 74.6% and the diffusing capacity for carbon monoxide was 63.6%. Treatment with pirfenidone was increased over time: 62.4% of IPF patients were treated with pirfenidone initially. And 79.2% of patients were treated with antifiboritics for more than three months during the course of the disease since 2016. Old age, acute exacerbation, treatment without antifibrotics, and exposure to wood and stone dust were associated with higher mortality. Conclusion: In the recent Korean IPF registry, the percentage of IPF patients treated with antifibrotics was increased compared to that in the previous IPF registry. Old age, acute exacerbation, treatment without antifibrotics, and exposure to wood and stone dust were associated with higher mortality.ope

COVID-19 Vaccine-Associated Pneumonitis in the Republic of Korea: A Nationwide Multicenter Survey

Background: Recent reports have suggested that pneumonitis is a rare complication following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, its clinical features and outcomes are not well known. The aim of this study was to identify the clinical characteristics and outcomes of patients with vaccine-associated pneumonitis following vaccination against SARS-CoV-2. Methods: In this nationwide multicenter survey study, questionnaires were distributed to pulmonary physicians in referral hospitals. They were asked to report cases of development or exacerbation of interstitial lung disease (ILD) associated with the coronavirus disease 2019 vaccine. Vaccine-associated pneumonitis was defined as new pulmonary infiltrates documented on chest computed tomography within 4 weeks of vaccination and exclusion of other possible etiologies. Results: From the survey, 49 cases of vaccine-associated pneumonitis were identified between February 27 and October 30, 2021. After multidisciplinary discussion, 46 cases were analyzed. The median age was 66 years and 28 (61%) were male. The median interval between vaccination and respiratory symptoms was 5 days. There were 20 (43%), 17 (37%), and nine (19%) patients with newly identified pneumonitis, exacerbation of pre-diagnosed ILD, and undetermined pre-existing ILD, respectively. The administered vaccines were BNT162b2 and ChAdOx1 nCov-19/AZD1222 each in 21 patients followed by mRNA-1273 in three, and Ad26. COV2.S in one patient. Except for five patients with mild disease, 41 (89%) patients were treated with corticosteroid. Significant improvement was observed in 26 (57%) patients including four patients who did not receive treatment. However, ILD aggravated in 9 (20%) patients despite treatment. Mortality was observed in eight (17%) patients. Conclusion: These results suggest pneumonitis as a potentially significant safety concern for vaccines against SARS-CoV-2. Clinical awareness and patient education are necessary for early recognition and prompt management. Additional research is warranted to identify the epidemiology and characterize the pathophysiology of vaccine-associated pneumonitis.ope

Two cases of imported paratyphoid fever with poor response to ciprofloxacin following travel to India

It is well known that paratyphoid fever is caused by Salmonella enterica serotype paratyphi (S. paratyphi) and usually responds to ciprofloxacin treatment. Recently, many reports have recommended that S. paratyphi with nalidixic acid resistance should be considered if paratyphoid fever does not improved with ciprofloxacin treatment. We experienced two patients who were diagnosed with paratyphoid fever after traveling to India. the paratyphoid fever was caused by ciprofloxacin-susceptible and intermediate S. paratyphi infection; however, the patients became refractory to treatment with ciprofloxacin. After 7 days of treatment with ciprofloxacin, we changed the antibiotic treatment to a third-generation cephalosporin. Sustained fever and watery diarrhea was improved within 3 days after changing the antibiotics. in uncomplicated cases of paratyphoid fever, an adequate dose of ciprofloxacin can be given initially. If clinical improvement is not noted after 3 to 5 days, however, third-generation cephalosporins should be considered as an alternative regimen.ope

New prognostic scoring system for mortality in idiopathic pulmonary fibrosis by modifying the gender, age, and physiology model with desaturation during the six-minute walk test

Background: Idiopathic pulmonary fibrosis (IPF) is a progressive fibrosing interstitial lung disease (ILD) with variable and heterogeneous clinical course. The GAP (gender, age, and physiology) model had been used to predict mortality in patients with IPF, but does not contain exercise capacity. Therefore, our aim in this study was to develop new prognostic scoring system in the Korea IPF Cohort (KICO) registry. Materials and methods: This is a retrospective study of Korean patients with IPF in KICO registry from June 2016 to August 2021. We developed new scoring system (the GAP6) based on the GAP model adding nadir saturation of percutaneous oxygen (SpO2) during six-minute walk test (6MWT) in the KICO registry and compared the efficacy of the GAP and the GAP6 model. Results: Among 2,412 patients in KICO registry, 966 patients were enrolled. The GAP6 model showed significant prognostic value for mortality between each stage [HR Stage II vs. Stage I = 2.89 (95% CI = 2.38–3.51), HR Stage III vs. Stage II = 2.68 (95% CI = 1.60–4.51)]. In comparison the model performance with area under curve (AUC) using receiver operating characteristic (ROC) curve analysis, the GAP6 model showed a significant improvement for predicting mortality than the GAP model (AUC the GAP vs. the GAP6, 0.646 vs. 0.671, p < 0.0019). Also, the C-index values slightly improved from 0.674 to 0.691 for mortality. Conclusion: The GAP6 model adding nadir SpO2 during 6WMT for an indicator of functional capacity improves prediction ability with C-index and AUC. Additional multinational study is needed to confirm these finding and validate the applicability and accuracy of this risk assessment system. Copyright © 2023 Lee, Jang, Jang, Kim, Chung, Yoo, Jeong, Song, Lee, Choi, Kim, Kim, Park, Park, Jegal, Lee, Uh, Kim, Kim, Shin, Lee, Yang, Lee, Kim, Lee, Choi, Kang, Heo, Lee and Park.ope

Factors affecting treatment outcome in patients with idiopathic nonspecific interstitial pneumonia: a nationwide cohort study

BACKGROUND: The effects of corticosteroid-based therapy in patients with idiopathic nonspecific interstitial pneumonia (iNSIP), and factors affecting treatment outcome, are not fully understood. We aimed to investigate the long-term treatment response and factors affecting the treatment outcome in iNSIP patients from a multi-center study in Korea. METHODS: The Korean interstitial lung disease (ILD) Study Group surveyed ILD patients from 2003 to 2007. Patients were divided into two groups to compare the treatment response: response group (forced vital capacity (FVC) improves ≥10% after 1 year) and non-response group (FVC <10%). Factors affecting treatment response were evaluated by multivariate logistic regression analysis. RESULTS: A total of 261 patients with iNSIP were enrolled, and 95 patients were followed-up for more than 1 year. Corticosteroid treatment was performed in 86 patients. The treatment group showed a significant improvement in lung function after 1-year: FVC, 10.0%; forced expiratory volume (FEV1), 9.8%; diffusing capacity of the lung for carbon monoxide (DLco), 8.4% (p < 0.001). Sero-negative anti-nuclear antibody (ANA) was significantly related with lung function improvement. Sero-positivity ANA was significantly lower in the response group (p = 0.013), compared to that in the non-response group. A shorter duration of respiratory symptoms at diagnosis was significantly associated with a good response to treatment (p = 0.018). CONCLUSION: Treatment with corticosteroids and/or immunosuppressants improved lung function in iNSIP patients, which was more pronounced in sero-negative ANA and shorter symptom duration patients. These findings suggest that early treatment should be considered in iNSIP patients, even in an early disease stage.ope

Predicting survival of patients with idiopathic pulmonary fibrosis using GAP score: a nationwide cohort study

BACKGROUND: The clinical course of idiopathic pulmonary fibrosis (IPF) varies widely. Although the GAP model is useful for predicting mortality, survivals have not yet been validated for each GAP score. We aimed to elucidate how prognosis is related to GAP score and GAP stage in IPF patients. METHODS: The Korean Interstitial Lung Disease Study Group conducted a national survey to evaluate various characteristics in IPF patients from 2003 to 2007. Patients were diagnosed according to the 2002 criteria of the ATS/ERS. We enrolled 1,685 patients with IPF; 1,262 had undergone DLCO measurement. Patients were stratified based on GAP score (0-7): GAP score Group 0 (n?=?26), Group 1 (n?=?150), Group 2 (n?=?208), Group 3 (n?=?376), Group 4 (n?=?317), Group 5 (n?=?138), Group 6 (n?=?39), and Group 7 (n?=?8). RESULTS: Higher GAP score and GAP stage were associated with a poorer prognosis (p?<?0.001, respectively). Survival time in Group 3 was lower than those in Groups 1 and 2 (p?=?0.043 and p?=?0.039, respectively), and higher than those in groups 4, 5, and 6 (p?=?0.043, p?=?0.032, and p?=?0.003, respectively). Gender, age, and DLCO (%) differed significantly between Groups 2 and 3. All four variables in the GAP model differed significantly between Groups 3 and 4. CONCLUSION: The GAP system showed significant predictive ability for mortality in IPF patients. However, prognosis in IPF patients with a GAP score of 3 were significantly different from those in the other stage I groups and stage II groups of Asian patients.ope

Comparison of CPI and GAP models in patients with idiopathic pulmonary fibrosis: a nationwide cohort study

The clinical course of idiopathic pulmonary fibrosis (IPF) is difficult to predict, partly owing to its heterogeneity. Composite physiologic index (CPI) and gender-age-physiology (GAP) models are easy-to-use predictors of IPF progression. This study aimed to compare the predictive values of these two models. From 2003 to 2007, the Korean Interstitial Lung Disease (ILD) Study Group surveyed ILD patients using the 2002 ATS/ERS criteria. A total of 832 patients with IPF were enrolled in this study. CPI was calculated as follows: 91.0 - (0.65 x %DLCO) - [0.53 x %FVC + [0.34 x %FEV1. GAP stage was calculated based on gender (0-1 points), age (0-2 points), and two physiologic lung function parameters (0-5 points). The two models had similar significant predictive values for patients with IPF (p < 0.001). The area under the curve (AUC) was higher for CPI than GAP for prediction of 1-, 2-, and 3-year mortality in this study. The AUC was higher for surgically diagnosed IPF patients than for clinically diagnosed patients. However, neither CPI nor GAP yielded good predictions of outcomes; the AUC was approximately 0.61~0.65. Although both CPI and GAP stage are significantly useful predictors for IPF, they have limited capability to accurately predict outcomes.ope