Forecasting of the COVID-19 pandemic situation of Korea

For the novel coronavirus disease 2019 (COVID-19), predictive modeling, in the literature, uses broadly susceptible exposed infected recoverd (SEIR)/SIR, agent-based, curve-fitting models. Governments and legislative bodies rely on insights from prediction models to suggest new policies and to assess the effectiveness of enforced policies. Therefore, access to accurate outbreak prediction models is essential to obtain insights into the likely spread and consequences of infectious diseases. The objective of this study is to predict the future COVID-19 situation of Korea. Here, we employed 5 models for this analysis; SEIR, local linear regression (LLR), negative binomial (NB) regression, segment Poisson, deep-learning based long short-term memory models (LSTM) and tree based gradient boosting machine (GBM). After prediction, model performance comparison was evelauated using relative mean squared errors (RMSE) for two sets of train (January 20, 2020‒December 31, 2020 and January 20, 2020‒January 31, 2021) and testing data (January 1, 2021‒February 28, 2021 and February 1, 2021‒February 28, 2021) . Except for segmented Poisson model, the other models predicted a decline in the daily confirmed cases in the country for the coming future. RMSE values’ comparison showed that LLR, GBM, SEIR, NB, and LSTM respectively, performed well in the forecasting of the pandemic situation of the country. A good understanding of the epidemic dynamics would greatly enhance the control and prevention of COVID-19 and other infectious diseases. Therefore, with increasing daily confirmed cases since this year, these results could help in the pandemic response by informing decisions about planning, resource allocation, and decision concerning social distancing policies.

Forecasting of the COVID-19 pandemic situation of Korea

For the novel coronavirus disease 2019 (COVID-19), predictive modeling, in the literature, uses broadly susceptible exposed infected recoverd (SEIR)/SIR, agent-based, curve-fitting models. Governments and legislative bodies rely on insights from prediction models to suggest new policies and to assess the effectiveness of enforced policies. Therefore, access to accurate outbreak prediction models is essential to obtain insights into the likely spread and consequences of infectious diseases. The objective of this study is to predict the future COVID-19 situation of Korea. Here, we employed 5 models for this analysis; SEIR, local linear regression (LLR), negative binomial (NB) regression, segment Poisson, deep-learning based long short-term memory models (LSTM) and tree based gradient boosting machine (GBM). After prediction, model performance comparison was evelauated using relative mean squared errors (RMSE) for two sets of train (January 20, 2020‒December 31, 2020 and January 20, 2020‒January 31, 2021) and testing data (January 1, 2021‒February 28, 2021 and February 1, 2021‒February 28, 2021) . Except for segmented Poisson model, the other models predicted a decline in the daily confirmed cases in the country for the coming future. RMSE values’ comparison showed that LLR, GBM, SEIR, NB, and LSTM respectively, performed well in the forecasting of the pandemic situation of the country. A good understanding of the epidemic dynamics would greatly enhance the control and prevention of COVID-19 and other infectious diseases. Therefore, with increasing daily confirmed cases since this year, these results could help in the pandemic response by informing decisions about planning, resource allocation, and decision concerning social distancing policies.

Religion and Health Behaviors in Primary Care Patients / 가정의학회지

Background@#Few studies have investigated the association between religion and health behaviors in Korea, where various religions coexist. The present study aimed to investigate the association between religion and health behaviors among primary care patients in Korea. @*Methods@#We analyzed data from the Family Cohort Study in Primary Care. Among the 1,040 participants in the cohort, 973 of those who had reported their religion were included in the analysis. Participants completed standardized questionnaires that included religious status and lifestyle factors, such as physical activity, smoking status, drinking status, and dietary habits. The association between religion and health behaviors was analyzed using multivariate logistic regression models. @*Results@#Among the 973 participants, 345 (35.5%) were Christian, 153 (15.7%) were Roman Catholic, 308 (31.7%) were Buddhist, and 163 (16.8%) did not have any religion. Compared with those without a religion, the odds ratio (OR) for vigorous physical activity (OR, 1.52; 95% confidence interval [CI], 1.01–2.28) increased, and that for binge drinking (OR, 0.67; 95% CI, 0.46–0.78) and problematic drinking (OR, 0.59; 95% CI, 0.35–0.99) decreased among participants with a religion. Compared with those without a religion, Catholics were more likely to engage in vigorous physical activity (OR, 2.20; 95% CI, 1.31–3.67), whereas Christians were less likely to engage in heavy (OR, 0.50; 95% CI, 0.30–0.84), binge (OR, 0.35; 95% CI, 0.22–0.54), and problematic drinking (OR, 0.46; 95% CI, 0.25–0.86). Smoking, meal regularity, and breakfast consumption were not associated with religion. @*Conclusion@#The status of drinking and physical activities were different according to religion. As religion is one of the psychosocial characteristics of patients, knowing patients’ religion can be helpful for primary physicians.

Genetic Alterations in Preinvasive Lung Synchronous Lesions / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Despite advances in treatment, lung cancer remains the leading cause of cancer mortality. This study aimed to characterise genome-wide tumorigenesis events and to understand the hypothesis of the multistep carcinogenesis of lung adenocarcinoma (LUAD) @*Materials and Methods@#We conducted multiregion whole-exome sequencing of LUAD with synchronous atypical adenomatous hyperplasia (AAH), adenocarcinoma in situ, or minimally invasive adenocarcinoma of 19 samples from three patients to characterize genome-wide tumorigenesis events and validate the hypothesis of the multistep carcinogenesis of LUAD. We identified potential pathogenic mutations preserved in preinvasive lesions and supplemented the finding by allelic variant level from RNA sequencing. @*Results@#Overall, independent mutational profiles were observed per patient and between patients. Some shared mutations including epidermal growth factor receptor (EGFR , p.L858R) were present across synchronous lesions. @*Conclusion@#Here, we show that there are driver gene mutations in AAH, and they may exacerbate as a sequence in a histological continuum, supporting the Darwinian evolution model of cancer genome. The intertumoral and intratumoral heterogeneity of synchronous LUAD implies that multi-biomarker strategies might be necessary for appropriate treatment.

Monitoring Glutathione Dynamics and Heterogeneity in Living Stem Cells

Glutathione (GSH) is a major antioxidant in cells, and plays vital roles in the cellular defense against oxidants and in the regulation of redox signals. In a previous report, we demonstrated that stem cell function is critically affected by heterogeneity and dynamic changes in cellular GSH concentration. Here, we present a detailed protocol for the monitoring of GSH concentration in living stem cells using FreSHtracer, a real-time GSH probe. We describe the steps involved in monitoring GSH concentration in single living stem cells using confocal microscopy and flow cytometry. These methods are simple, rapid, and quantitative, and able to demonstrate intracellular GSH concentration changes in real time. We also describe the application of FreSHtracer to the sorting of stem cells according to their GSH content using flow cytometry. Typically, microscopic or flow cytometric analyses of FreSHtracer and MitoFreSHtracer signals in living stem cells take ~2~3 h, and the fractionation of stem cells into subpopulations on the basis of cellular GSH levels takes 3~4.5 h. This method could be applied to almost every kind of mammalian cell with minor modifications to the protocol described here.

Health Behaviors and Lifestyle Patterns of Elderly Living Alone in Korea

BACKGROUND: Korea's population is aging rapidly. Aged people who lead a solitary life are in a state of social isolation and face a greater risk of lower quality of life. The purpose of this study was to analyze the health behaviors and lifestyle patterns of aged people who lead a solitary life in Korea.METHODS: We analyzed 4,471 subjects (1,933 men and 2,538 women)-aged people aged 65 or above-based on data from the Korea National Health and Nutrition Examination Survey VI (2013–2015). The odds ratios (ORs) and 95% confidence intervals (CIs) were analyzed using multivariate logistic regression analysis adjusted with age, household income level, occupational status, and geographical region.RESULTS: Socioeconomic status was lower in aged people who lead a solitary life than in those living with family. The ORs for frequent eating out alone (OR=2.93; 95% CI 1.83–4.38), daily eating out alone (OR=2.40; 95% CI 1.25–4.60), smoking (OR=1.57; 95% CI 1.06–2.32), feeling sick or uncomfortable (OR=1.59; 95% CI 1.08–2.36), feeling depressed (OR=4.10; 95% CI 2.53–6.65), and suicide ideation (OR=2.06; 95% CI 1.21–3.51) were significantly higher in male subjects who lead a solitary life. The ORs for frequent eating out alone (OR=1.57; 95% CI 1.10–2.24) and inadequate sleep duration (OR=1.29; 95% CI 1.03–1.61) were significantly higher in female subjects who lead a solitary life.CONCLUSION: Aged people who lead a solitary life exhibited unhealthy behaviors and poor mental health. The elderly men who lead a solitary life faced higher risk of poor health than the women. Integrated management of lifestyle behaviors is required to improve the quality of health in aged people who lead a solitary life.

Factors Affecting Adherence to Antihypertensive Medication / 가정의학회지

BACKGROUND: Hypertension is a major contributor to the global disease burden of cardiovascular and cerebrovascular disease. The aim of this study was to determine demographic and clinical factors associated with adherence to antihypertensive medication. METHODS: From August 2012 to February 2015, we recruited 1,523 Korean patients with hypertension who visited family physicians. The study was conducted in 24 facilities located in urban and metropolitan areas. Of these facilities, two were primary care clinics and 22 were level 2 or 3 hospitals. Adherence was assessed using the pill count method; a cut-off value of 80% was used as the criterion for good adherence. Sociodemographic and lifestyle factors were compared between the adherent and nonadherent groups using the chi-square test for categorical variables and t-test for continuous variables. Binary logistic regression analysis was performed with medication adherence as the outcome variable. RESULTS: Of the 1,523 patients, 1,245 (81.7%) showed good adherence to antihypertensive medication. In the multivariate logistic analysis, age ≥65 years, exercise, treatment in a metropolitan-located hospital, being on ≥2 classes of antihypertensive medication and concomitant medication for diabetes, and a family history of hypertension or cardiovascular diseases were associated with good adherence. Patients who had a habit of high salt intake were less adherent to medication. CONCLUSION: Multiple classes of antihypertensive medications, concomitant medication, and exercise were associated with good adherence to antihypertensive medication, and high salt intake was associated with poor adherence to antihypertensive medication. These factors should be considered to improve hypertension control.

The Therapeutic Effect of Human Embryonic Stem Cell-Derived Multipotent Mesenchymal Stem Cells on Chemical-Induced Cystitis in Rats / 대한배뇨장애요실금학회지

PURPOSE: To evaluate the therapeutic effect of human embryonic stem cell (hESC)-derived multipotent mesenchymal stem cells (M-MSCs) on ketamine-induced cystitis (KC) in rats. METHODS: To induce KC, 10-week-old female rats were injected with 25-mg/kg ketamine hydrochloride twice weekly for 12 weeks. In the sham group, phosphate buffered saline (PBS) was injected instead of ketamine. One week after the final injection of ketamine, the indicated doses (0.25, 0.5, and 1×106 cells) of M-MSCs (KC+M-MSC group) or PBS vehicle (KC group) were directly injected into the bladder wall. One week after M-MSC injection, the therapeutic outcomes were evaluated via cystometry, histological analyses, and measurement of gene expression. Next, we compared the efficacy of M-MSCs at a low dose (1×105 cells) to that of an identical dose of adult bone marrow (BM)-derived MSCs. RESULTS: Rats in the KC group exhibited increased voiding frequency and reduced bladder capacity compared to rats of the sham group. However, these parameters recovered after transplantation of M-MSCs at all doses tested. KC bladders exhibited markedly increased mast cell infiltration, apoptosis, and tissue fibrosis. Administration of M-MSCs significantly reversed these characteristic histological alterations. Gene expression analyses indicated that several genes associated with tissue fibrosis were markedly upregulated in KC bladders. However the expression of these genes was significantly suppressed by the administration of M-MSCs. Importantly, M-MSCs ameliorated bladder deterioration in KC rats after injection of a low dose (1×105) of cells, at which point BM-derived MSCs did not substantially improve bladder function. CONCLUSIONS: This study demonstrates for the first time the therapeutic efficacy of hESC-derived M-MSCs on KC in rats. M-MSCs restored bladder function more effectively than did BM-derived MSCs, protecting against abnormal changes including mast cell infiltration, apoptosis and fibrotic damage.

Determination of the Main Theme and Tasks for an Obesity Educator Training Program

After discussion about the need to develop an obesity educator training program and certification for obesity educators, the Education Committee of the Korean Society for the Study of Obesity has developed and determined the main theme for the Obesity Educator Training Program implemented as a workshop and public hearing. We reviewed the process of the determination of the main theme and discuss topics such as subjects, operation of the program, and certification processing to design a credible obesity educator training program.

The Molecular Nature of Very Small Embryonic-Like Stem Cells in Adult Tissues

Pluripotent stem cells (PSCs) have been considered as the most important cells in regenerative medicine as they are able to differentiate into all types of cells in the human body. PSCs have been established from several sources of embryo tissue or by reprogramming of terminally differentiated adult tissue by transduction of so-called Yamanaka factors (Oct4, Sox2, Klf4, and cMyc). Interestingly, accumulating evidence has demonstrated the residence of PSCs in adult tissue and with the ability to differentiate into multiple types of tissue-committed stem cells (TCSCs). We also recently demonstrated that a population of pluripotent Oct4(+) SSEA-1(+)Sca-1(+)Lin-CD45(-) very small embryonic-like stem cells (VSELs) resides in the adult murine bone marrow (BM) and in other murine tissue. These very small (~3-6 microm) cells express pluripotent markers such as Oct4, Nanog, and SSEA-1. VSELs could be specified into several tissue-residing TCSCs in response to tissue/organ injury, and thus suggesting that these cells have a physiological role in the rejuvenation of a pool of TCSCs under steady-state conditions. In this review article, we discuss the molecular nature of the rare population of VSELs which have a crucial role in regulating the pluripotency, proliferation, differentiation, and aging of these cells.