Active and prompt scale-up screening tests are essential to efficiently control the coronavirus disease 2019 (COVID-19) outbreak. The goal of this work was to identify shortcomings in the conventional screening system (CSS) implemented in the beginning of the outbreak. To overcome these shortcomings, we then introduced a novel, independently developed system called the Yeungnam University type drive-through (YU-Thru), and distributed it nationwide in Korea. This system is similar to the drive-throughs utilized by fast food restaurants. YU-Thru system has shortened the time taken to test a single person to 2–4 minutes, by completely eliminating the time required to clean and ventilate the specimen collection room. This time requirement was a major drawback of the CSS. YU-Thru system also reduced the risk of subjects and medical staff infecting one another by using a separate and closed examination system. On average, 50 to 60 tests were conducted per day when using the CSS, while now up to 350 tests per day are conducted with the YU-Thru system. We believe that the YU-Thru system has made an important contribution to the rapid detection of COVID-19 in Daegu, South Korea. Here, we will describe the YU-Thru system in detail so that other countries experiencing COVID-19 outbreaks can take advantage of this system.

To investigate the prevalence of Toxoplasma gondii in pork on the market in Korea, an in-house enzyme-linked immunosorbent assay for tissue fluid (CAU-tf-ELISA) was developed using a soluble extract of T. gondii RH strain tachyzoites. As the standard positive controls, the piglets were experimentally infected with T. gondii: Group A (1,000 cysts-containing bradyzoites), Group B (500 cysts-containing bradyzoites) and Group C (1.0×103 or 1.0×104 tachyzoites). The CAU-tf-ELISA demonstrated infection intensity-dependent positivity toward tissue fluids with average cut-off value 0.15: 100% for Group A, 93.8% for Group B and 40.6% for Group C. When tissue-specific cut-off values 0.066–0.199 were applied, CAU-tf-ELISA showed 96.7% sensitivity, 100% specificity, 100% positive and 90.0% negative predictive values. When compared with the same tissue fluids, performance of CAU-tf-ELISA was better than that of a commercial ELISA kit. Of the 583 Korea domestic pork samples tested, anti-T. gondii antibodies were detected from 9.1% of whole samples and 37.9% from skirt meat highest among pork parts. In the 386 imported frozen pork samples, 1.8% (skirt meat and shoulder blade) were positive for anti-T. gondii antibodies. In Korea, prevalence of anti-T. gondii antibodies in the pork on retail markets appeared high, suggesting that regulations on pig farming and facilities are necessary to supply safe pork on the tables.
Agriculture ; Antibodies ; Enzyme-Linked Immunosorbent Assay ; Korea ; Meat ; Prevalence ; Red Meat ; Sensitivity and Specificity ; Shoulder ; Social Control, Formal ; Toxoplasma

OBJECTIVE: To determine whether fragment removal on in vitro fertilization (IVF) day 2 improved the subsequent development and pregnancy outcomes of fragmented embryos compared to similar-grade embryos without fragment removal. METHODS: This study was a retrospective analysis involving 191 IVF cycles in which all embryos had over 10% fragmentation (grade 3 or 4) on day 2 of the IVF-embryo transfer cycle from March 2015 to December 2017. IVF cycles were divided into the fragment removal group (n=87) and the no fragment removal group (n=104) as a control cohort. Before fragment removal, embryos with fragmentation on day 2 were incubated in Ca2+- and Mg2+-free biopsy medium under paraffin oil for 30 minutes. Microsurgical fragment removal was performed with later-assisted hatching and a handmade suction micropipette that had an outer diameter of 30 µm. RESULTS: There were no significant differences in the characteristics of the patients between the control and the fragment removal groups. After fragment removal and subsequent in vitro culture for 24 hours, the number of blastomeres (7.1±1.7 vs. 6.9±1.6) was comparable between the transferred embryos in the two groups, but the morphological grade of the embryos in the fragment removal group (1.9±0.7) was significantly higher than that of the control group (3.1±0.5, p < 0.01). The clinical pregnancy (43.7%) and implantation rates (25.8%) in the fragment removal group were significantly higher than those in the control group (28.8% and 14.0%, respectively; p < 0.05). CONCLUSION: Early fragment removal on day 2 significantly improved the subsequent development and pregnancy outcomes of fragmented embryos.
Biopsy ; Blastomeres ; Cohort Studies ; Embryonic Structures* ; Female ; Fertilization in Vitro* ; Humans* ; In Vitro Techniques* ; Paraffin ; Pregnancy ; Pregnancy Outcome ; Retrospective Studies ; Suction

OBJECTIVE: Correlations between semen parameters and sperm DNA fragmentation index (DFI) were investigated to identify characteristics of sperm without DNA damage that could be used in selecting sperm for intracytoplasmic sperm injection (ICSI). Pregnancy outcomes were compared to determine whether in vitro fertilization (IVF) or ICSI is a better choice for patients who have sperm with a high-DFI. METHODS: Semen analysis was carried out in 388 patients who visited our IVF center for the first time to investigate correlations between sperm DFI and semen parameters. In addition, 1,102 IVF cycles in 867 patients were carried out in the present study; 921 cycles in the low-DFI group (DFI <30%) and 181 cycles in the high-DFI group (DFI ≥30%). Both the low- and high-DFI groups were subdivided into IVF and ICSI cycle groups. RESULTS: Sperm DFI showed significant inverse correlations with sperm motility (r=−0.435, p<0.001) and morphology (r=−0.153, p<0.05). Sperm DFI also showed significant correlations with rapid motility (r=−0.436, p<0.001), and the kinetic parameters of average-path velocity (r=−0.403) and linearity (r=−0.412). Although there was no significant difference in the pregnancy rates between IVF (48.6%) and ICSI (44.8%) in the low-DFI group, the pregnancy rate of ICSI cycles (44.8%, p<0.05) was significantly higher than IVF cycles (25.0%) in the high-DFI group. No significant difference was observed in the abortion rates between the low-DFI (52 of 921, 5.6%) and high-DFI groups (7 of 181, 3.8%). CONCLUSION: ICSI is a better choice than IVF for improving the pregnancy outcomes of patients who have sperm with a high DFI.
Abortion, Induced ; DNA Damage ; DNA Fragmentation* ; DNA* ; Female ; Fertilization in Vitro ; Humans ; Pregnancy Outcome ; Pregnancy Rate* ; Pregnancy* ; Semen ; Semen Analysis ; Sperm Injections, Intracytoplasmic* ; Sperm Motility ; Spermatozoa*

OBJECTIVE: Cholinergic nicotinic receptor (CHRN) gene family has been known to mediate the highly additive effects of nicotine in the body, and implicated nicotine dependence (ND) and related phenotypes. Previous studies have found that CHRNA6-CHRNB3 cluster polymorphisms were significantly associated with the risk of ND and various tobacco behaviors. The aim of study was to evaluate the genetic association of CHRNB3 and CHRNA6 polymorphisms with the risk of ND based on the Fagerstrom Test for Nicotine Dependence (FTND) score and five subscales of nicotine dependence syndrome scale (NDSS) in Korean population. METHODS: Six SNPs in CHRNA6-CHRNB3 cluster were analyzed in 576 Korean subjects. Association analysis using logistic models and regression analysis with NDSS were performed. RESULTS: There was no association in the case-control analysis, whereas all six SNPs were significantly associated with drive factor among NDSS in subgroup based on the FTND score. CHRNB3 rs4954 and CHRNA6 rs16891604 showed significant associations with NDSSF1 (drive) in dominant models among moderate to severe ND among smokers after correction (p(corr)=0.02 and 0.001, respectively), whereas other four SNPs showed significant associations among mild ND after correction (p(corr)=0.03-0.02 in dominant model). CONCLUSION: This study showed that the genetic influence of CHRNB3-CHRNA6 cluster polymorphisms are found in a ND endophenotype (drive) using NDSS subscales, rather than the risk of ND in Korean population. Our findings might be the first report for the association of CHRNB3-CHRNA6 cluster with ND-related phenotypes in Korean and might offer an approach to elucidating the molecular mechanisms of ND and ND-related phenotypes.
Case-Control Studies ; Endophenotypes ; Humans ; Logistic Models ; Nicotine ; Phenotype ; Polymorphism, Single Nucleotide ; Receptors, Nicotinic ; Tobacco ; Tobacco Use Disorder*

OBJECTIVE: Cigarette smoking is associated with a variety of health problems including cardiovascular, pulmonary, neoplasms, endocrinopathies including diabetes, the metabolic syndrome, and chronic inflammation. Adiponectin is an adipocyte-derived plasma protein that is closely associated with insulin sensitivity and the metabolic syndrome. The aim of this study was to evaluate the changes of plasma adiponectin levels after smoking cessation. METHODS: Thirty seven smokers that wanted to stop smoking without any nicotine replacement therapy or medication were recruited for this study. Fifteen smokers succeeded in stopping smoking (validated by urine cotinine levels < or =50 ng/mL) and 22 smokers failed. Therefore, only the 15 that succeeded were included in the analysis. The plasma adiponectin levels were determined using a commercially available enzyme-linked immunosorbent assay. RESULTS: The mean age of the successful 15 was 35+/-9.3 years old. They were all males. The daily smoking habit was a mean of 13.5+/-5.4 cigarettes per day. The mean Nicotine Dependence Syndrome Scale (NDSS) and Fagerstrom Test for Nicotine Dependence (FTND) scores were 55.6+/-9.6 and 2.9+/-1.9. During the study period of three months, the mean body mass index (BMI), body fat mass (BFM), waist-hip ratio (WHR) and body weight increased by 1.1 kg/m2, 3.0%, 0.02%, and 2.9 kg, respectively. The baseline mean adiponectin level in the subjects was 11.9+/-5.2 mg/L. The mean adiponectin levels measured at one and three months were 16.0+/-5.1 mg/L and 14.7+/-4.5 mg/L respectively. The mean plasma adiponectin levels of the successful group was significantly increased after four weeks when compared to the baseline (z=-2.401, p=0.016). However, the decrease in plasma adiponectin levels at one and three months was not statistically significant. CONCLUSION: Even though the decrease over the next two months was not significant, these findings, the increase of plasma level of adiponectin after smoking cessation, provide preliminary data for future research on the possible mechanisms associated with smoking cessation and changes in body metabolism.
Adiponectin* ; Adipose Tissue ; Body Mass Index ; Body Weight ; Cotinine ; Enzyme-Linked Immunosorbent Assay ; Ghrelin ; Humans ; Inflammation ; Insulin Resistance ; Leptin ; Male ; Metabolism ; Nicotine ; Plasma* ; Smoke* ; Smoking Cessation* ; Smoking* ; Tobacco ; Tobacco Products ; Tobacco Use Disorder ; Waist-Hip Ratio

OBJECTIVE: Our aim was to evaluate the changes in blood glucose control and lipid profiles after 2-months of smoking cessation in healthy males. METHODS: Smoking abstinence was evaluated through self-report and urine cotinine levels. 12 individuals who succeeded in quitting smoking were analyzed. Fasting values of glucose and insulin were used to estimate the beta-cell activity and insulin resistance was evaluated using the Homeostasis Model Assessment (HOMA) and Quantitative Insulin Sensitivity Check Index (QUICKI). RESULTS: The data showed that the subjects had a significant increase in weight, body mass index and fasting plasma glucose levels after smoking cessation. The HOMA-Insulin Resistance and the HOMA beta-cell function increased significantly (p=0.005, p=0.047 respectively). The QUICKI showed a significant decrease (p=0.005). In addition, the low-density lipoprotein cholesterol levels decreased significantly (p=0.028); however, changes in the high-density lipoprotein cholesterol, the triglyceride and total cholesterol levels were not significant (p=0.284, p=0.445 respectively). CONCLUSION: During the initial stage of smoking abstinence, insulin resistance increased and insulin sensitivity decreased due to elevated body weight and fat composition. Therefore, it is important to educate individuals that stop smoking about the necessity of weight control during smoking cessation programs.
Blood Glucose ; Body Weight ; Cholesterol ; Cotinine ; Fasting ; Glucose ; Homeostasis ; Humans ; Insulin ; Insulin Resistance ; Lipoproteins ; Male ; Plasma ; Smoke ; Smoking ; Smoking Cessation

OBJECTIVES: It is well-known that tobacco smoking is related to various disease entities including chronic obstructive pulmonary disease, inflammation, cardiovascular disease, and neoplasms. The prohibition of smoking is important for the protection of these health problems. Regarding leptin, ghrelin, glucagon-like peptide 1 (GLP-1), and nerve growth factor (NGF) levels, correlations with the smoking are suggested but the reports on the effects after smoking cessation are not sufficient. METHOD: The changes of plasma levels of leptin, ghrelin, GLP-1, and NGF levels were analyzed after quitting smoking in Korean adults. Eleven participants succeeding in quitting smoking among 37 male smokers were included in the final analysis. The plasma levels of NGF, leptin, ghrelin, and GLP-1 were measured before and after 8-weeks period of smoking cessation. RESULTS: The plasma level of leptin increased after 4 weeks of smoking cessation. In addition, the plasma level of NGF increased after 8 weeks of smoking cessation (p < 0.05). CONCLUSION: Our results suggested that smoking cessation induces increases in leptin and the NGF level after smoking cessation. Many toxic materials including nicotine in the cigarette may be related to these changes of plasma level of leptin and NGF, playing a key role in neurogenesis and synaptic plasticity.
Adult ; Cardiovascular Diseases ; Ghrelin ; Glucagon-Like Peptide 1 ; Humans ; Inflammation ; Leptin ; Male ; Nerve Growth Factor ; Neurogenesis ; Nicotine ; Plasma ; Plastics ; Pulmonary Disease, Chronic Obstructive ; Smoke ; Smoking ; Smoking Cessation ; Tobacco ; Tobacco Products

OBJECTIVES: This cross-sectional study investigated the relationship between job stress and psychosocial stress among nurses at a university hospital in Incheon, Korea. METHODS: A questionnaire survey was administered to 476 nurses, of which 320 (67.2%) questionnaires were returned and 299 (62.8%) were regarded as containing reliable data for analyses. A structured self-reported questionnaire was used to assess each respondent's sociodemographics, sleep quality, physical burden, job stress and psychosocial stress. Seven domains of occupational stress (e.g., Job demand, Insufficient job control, Interpersonal conflict, Job insecurity, Lack of reward, Organizational system and Occupational climates) according to the Korean Occupational Stress Scale (KOSS) were used and psychosocial stress was measured using Dr. Chang's PWI-SF (Psychosocial Well-being Index-Short Form). We estimated the relation of job stress to psychosocial stress using univariate and logistic regression analyses. RESULTS: The logistic regression analyses indicated that the groups with high stress in 'Insufficient job control' (OR=2.67, 95% C.I.=1.37-5.23), 'Interpersonal conflict' (OR=2.32, 95% C.I.=1.19-4.51), 'Job insecurity' (OR=2.51, 95% C.I.=1.17-5.36), 'Organizational system' (OR=2.80, 95% C.I.=1.39-5.63), and 'Lack of reward' (OR=2.98, 95% C.I.=1.55-5.74) were more likely to experience high psychosocial stress. CONCLUSIONS: Our results tend to suggest that job stress is associated with psychosocial stress. The importance of job stress should be acknowledged and stress management programs need to be instigated to minimize the psychosocial stress caused by job stress.
Cross-Sectional Studies ; Incheon ; Korea ; Logistic Models ; Questionnaires ; Reward

PURPOSE: Appropriate reference values are needed for assessment of pulmonary function during childhood. We performed pulmonary function test with simple computerized spirometry to establish reference values of air flow rates in healthy Korean children. METHODS: We examined 1,317 children aged 6 to 15 years at their schools by standardized method during May, 2001. The children with poor cooperation, respiratory symptom, and chronic disease were excluded. Regression analysis was applied for FVC, FEV1, PEF, FEF25-75% predicted from sex, age, standing height, weight, and body surface area. RESULTS: In 1,317 children(Male : 716, Female : 601), the distribution of height was from 106.7 cm to 173.5 cm, weight was from 16.5 kg to 75.5 kg. We could get regression equations and determinant coefficients between anthropometric parameters and air flow rates. In both sexes, height showed very close correlation with lung function variables, and FEV1 showed very close correlation with all anthropometric parameters. Reference values of pulmonary function test were generally higher in boys than in girls. CONCLUSION: After performing the pulmonary function test in healthy Korean children, we report their normal values of air flow rates and regression equations for the predicted values. Among anthropometric parameters, height showed most close correlation with lung function variables in both sexes.
Body Surface Area ; Child* ; Chronic Disease ; Female ; Humans ; Lung* ; Reference Values* ; Respiratory Function Tests ; Spirometry