Background/Aims: Appropriate tissue tension and clear visibility of the dissection area using traction are essential for effective and safe endoscopic submucosal dissection (ESD). In this study, we developed a retractable robot-assisted traction device and evaluated its performance in colorectal ESD. Methods: An experienced endoscopist performed ESD 18 times on an ex vivo porcine colon using the robot and 18 times using the conventional method. The outcome measures were procedure time, dissection speed, procedure-related adverse events, and blind dissection rate. Results: Thirty-six colonic lesions were resected from ex vivo porcine colon samples. The total procedure time was significantly shorter in robot-assisted ESD (RESD) than in conventional ESD (CESD) (20.1±4.1 minutes vs 34.3±8.3 minutes, p<0.05). The submucosal dissection speed was significantly faster in the RESD group than in the CESD group (36.8±9.2 mm 2 /min vs 18.1±4.7 mm 2 /min, p<0.05). The blind dissection rate was also significantly lower in the RESD group (12.8%±3.4% vs 35.1%±3.9%, p<0.05). In an in vivo porcine feasibility study, the robotic device was attached to a colonoscope and successfully inserted into the proximal colon without damaging the colonic wall, and ESD was successfully performed. Conclusions The dissection speed and safety profile improved significantly with the retractable RESD. Thus, our robotic device has the potential to provide simple, effective, and safe multidirectional traction during colonic ESD.

Purpose: Cardiovascular disease is one of the major causes of death not only in Korea but also worldwide. Atherogenic index of plasma (AIP) has been extensively investigated, but studies on nutritional intake and eating habits are scarce. The purpose of this study was to analyze the general characteristics, dietary habits, and nutritional status of Korean adults based on their AIP values using data from the 2013–2015 Korea National Health and Nutrition Examination Survey. Methods: A total number of 3,040 adults in their 20s and 30s were included as study subjects. They were divided into quintiles according to their AIP values. Comparisons were then made among the general information, eating habits, and nutritional intake statuses of the groups. Results: The averages of AIP were different by age, obese status, education, occupation, alcohol drinking frequency, smoking, and exercise in men. As for women, the averages of AIP were different by age, obese status, education, occupation, alcohol drinking frequency, and smoking status. Except for high-density lipoprotein (HDL)-cholesterol, higher AIP values in men were associated with significant increasing trends in health indicators, including systolic and diastolic blood pressure, fasting blood glucose, insulin, hemoglobin A1c, total cholesterol, triglyceride, and low-density lipoprotein (LDL)-cholesterol. As for women, as AIP increased, systolic and diastolic blood pressure, fasting blood glucose, insulin, total cholesterol, triglyceride, and LDL-cholesterol showed significant increasing trends except HDL-cholesterol. HDL-cholesterol showed a significant decreasing trend as AIP increased in men and women. In the high AIP group of women, the frequency of breakfast was lower, whereas the frequency of alcohol beverage consumption was higher. Conclusion Among young adults, the risk of arteriosclerosis was higher in obese, smoking, and non-exercise individuals. More frequent alcohol drink consumption in women is associated with a higher risk of arteriosclerosis. Therefore, weight and lifestyle management are necessary for the prevention of atherosclerosis among young adults.

Purpose: The purpose of this study was to assess characteristics of SJ-815, a novel oncolytic vaccinia virus lacking a functional thymidine kinase-encoding TK gene, and instead, having two human transgenes: the IFNB1 that encodes interferon β1, and the CES2 that encodes carboxylesterase 2, which metabolizes the prodrug, irinotecan, into cytotoxic SN-38. Materials and Methods: Viral replication and dissemination of SJ-815 were measured by plaque assay and comet assay, respectively, and compared to the backbone of SJ-815, a modified Western Reserve virus named WI. Tumor cytotoxicity of SJ-815 (or mSJ-815, which has the murine IFNB1 transgene for mouse cancers) was evaluated using human and mouse cancer cells. Antitumor effects of SJ-815, with/without irinotecan, were evaluated using a human pancreatic cancer-bearing mouse model and a syngeneic melanoma-bearing mouse model. The SN-38/ irinotecan ratios in mouse melanoma tissue 4 days post irinotecan treatment were compared between groups with and without SJ-815 intravenous injection. Results: SJ-815 demonstrated significantly lower viral replication and dissemination, but considerably stronger in vitro tumor cytotoxicity than WI. The combination use of SJ-815 plus irinotecan generated substantial tumor regression in the human pancreatic cancer model, and significantly prolonged survival in the melanoma model (hazard ratio, 0.11; 95% confidence interval, 0.02 to 0.50; p=0.013). The tumor SN-38/irinotecan ratios were over 3-fold higher in the group with SJ-815 than those without (p < 0.001). Conclusion SJ-815 demonstrates distinct characteristics gained from the inserted IFNB1 and CES2 transgenes. The potent antitumor effects of SJ-815, particularly when combined with irinotecan, against multiple solid tumors make SJ-815 an attractive candidate for further preclinical and clinical studies.

BACKGROUND: Information about the epidemiology of venous thromboembolism (VTE) recurrence in Korea is lacking. The purpose of this study was to investigate VTE cumulative recurrence rates and identify risk factors for VTE recurrence among Korean adults. METHODS: A retrospective cohort study was conducted on adult patients (≥18 years) admitted to a university teaching hospital for pulmonary embolism (PE) from 2005 to 2013. The main outcome of interest was a recurrence of VTE. We used Cox proportional hazard regression analyses to calculate the relative risk of VTE recurrence. RESULTS: Five-year cumulative incidence of recurrent VTE events was 21.5% (95% confidence interval [CI], 17.7–25.4) in all cases of PE; 17% after provoked and 27% after unprovoked PE. Multivariate analysis showed that body mass index (BMI) of ≥25 (hazard ratio [HR], 2.02; 95% CI, 1.17–3.46; p=0.01) and longer anticoagulation therapy duration (HR, 0.90; 95% CI, 0.84–0.96; p<0.01) were independently associated with risk of VTE recurrence. Risk factors not found to be statistically significant at the <0.05 level included history of VTE (HR, 1.81; 95% CI, 0.84–3.88; p=0.12), unprovoked PE (HR, 1.70; 95% CI, 0.89–3.25; p=0.10), symptomatic deep vein thrombosis (HR, 1.62; 95% CI, 0.89–2.94; p=0.10), and female sex (HR, 1.42; 95% CI, 0.78–2.55; p=0.24). We found that age, history of cancer, and other co-morbidities did not significantly affect the risk of VTE recurrence. CONCLUSION Recurrence of VTE after PE is high. Patients with BMI ≥25 or reduced anticoagulation therapy duration have a higher risk of recurrent VTE.

BACKGROUND: Information about the epidemiology of venous thromboembolism (VTE) recurrence in Korea is lacking. The purpose of this study was to investigate VTE cumulative recurrence rates and identify risk factors for VTE recurrence among Korean adults. METHODS: A retrospective cohort study was conducted on adult patients (≥18 years) admitted to a university teaching hospital for pulmonary embolism (PE) from 2005 to 2013. The main outcome of interest was a recurrence of VTE. We used Cox proportional hazard regression analyses to calculate the relative risk of VTE recurrence. RESULTS: Five-year cumulative incidence of recurrent VTE events was 21.5% (95% confidence interval [CI], 17.7–25.4) in all cases of PE; 17% after provoked and 27% after unprovoked PE. Multivariate analysis showed that body mass index (BMI) of ≥25 (hazard ratio [HR], 2.02; 95% CI, 1.17–3.46; p=0.01) and longer anticoagulation therapy duration (HR, 0.90; 95% CI, 0.84–0.96; p<0.01) were independently associated with risk of VTE recurrence. Risk factors not found to be statistically significant at the <0.05 level included history of VTE (HR, 1.81; 95% CI, 0.84–3.88; p=0.12), unprovoked PE (HR, 1.70; 95% CI, 0.89–3.25; p=0.10), symptomatic deep vein thrombosis (HR, 1.62; 95% CI, 0.89–2.94; p=0.10), and female sex (HR, 1.42; 95% CI, 0.78–2.55; p=0.24). We found that age, history of cancer, and other co-morbidities did not significantly affect the risk of VTE recurrence. CONCLUSION: Recurrence of VTE after PE is high. Patients with BMI ≥25 or reduced anticoagulation therapy duration have a higher risk of recurrent VTE.
Adult ; Body Mass Index ; Cohort Studies ; Epidemiology ; Female ; Hospitals, Teaching ; Humans ; Incidence ; Korea ; Multivariate Analysis ; Pulmonary Embolism ; Recurrence ; Retrospective Studies ; Risk Factors ; Venous Thromboembolism ; Venous Thrombosis

BACKGROUND AND PURPOSE: Epidemiological studies have suggested the presence of strong correlations among diet, lifestyle, and dementia onset. However, these studies have unfortunately had major limitations due to their inability to fully control the various potential confounders affecting the nutritional status. The purpose of the current study was to determine the nutritional status of participants in the Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's Disease (KBASE) and to identify clinical risk factors for being at risk of malnutrition or being malnourished. METHODS: Baseline data from 212 participants [119 cognitively unimpaired (CU), 56 with mild cognitive impairment (MCI), and 37 with dementia] included in the KBASE database were analyzed. All participants underwent a comprehensive cognitive test and MRI at baseline. The presence of malnutrition at baseline was measured by the Mini Nutritional Assessment score. We examined the cross-sectional relationships of clinical findings with nutritional status using multiple logistic regression applied to variables for which p<0.2 in the univariate analysis. Differences in cortical thickness according to the nutritional status were also investigated. RESULTS: After adjustment for demographic, nutritional, and neuropsychological factors, participants with dementia had a significantly higher odds ratio (OR) for being at risk of malnutrition or being malnourished than CU participants [OR=5.98, 95% CI=1.20–32.97] whereas participants with MCI did not (OR=0.62, 95% CI=0.20–1.83). Cortical thinning in the at-risk/malnutrition group was observed in the left temporal area. CONCLUSIONS: Dementia was found to be an independent predictor for the risk of malnutrition compared with CU participants. Our findings further suggest that cortical thinning in left temporal regions is related to the nutritional status.
Aged ; Aging ; Alzheimer Disease ; Brain ; Cerebral Cortex ; Dementia ; Diet ; Early Diagnosis ; Epidemiologic Studies ; Humans ; Life Style ; Logistic Models ; Magnetic Resonance Imaging ; Malnutrition ; Mild Cognitive Impairment ; Nutrition Assessment ; Nutritional Status ; Odds Ratio ; Risk Factors ; Temporal Lobe

BACKGROUND AND PURPOSE: Visual assessment of medial temporal-lobe atrophy (MTA) has been quick, reliable, and easy to apply in routine clinical practice. However, one of the limitations in visual assessments of MTA is the lack of widely accepted age-adjusted norms and cutoff scores for MTA for a diagnosis of Alzheimer's disease (AD). This study aimed to determine the optimal cutoff score on a T1-weighted axial MTA Visual Rating Scale (VRS) for differentiating patients with AD from cognitively normal elderly people. METHODS: The 3,430 recruited subjects comprising 1,427 with no cognitive impairment (NC) and 2003 AD patients were divided into age ranges of 50–59, 60–69, 70–79, and 80–89 years. Of these, 446 participants (218 in the NC group and 228 in the AD group) were chosen by random sampling for inclusion in this study. Each decade age group included 57 individuals, with the exception of 47 subjects being included in the 80- to 89-year NC group. The scores on the T1-weighted axial MTA VRS were graded by two neurologists. The cutoff values were evaluated from the area under the receiver operating characteristic curve. RESULTS: The optimal axial MTA VRS cutoff score from discriminating AD from NC increased with age: it was ≥as ≥1, ≥2, and ≥3 in subjects aged 50–59, 60–69, 70–79, and 80–89 years, respectively (all p < 0.001). CONCLUSIONS: These results show that the optimal cutoff score on the axial MTA VRS for diagnosing of AD differed according to the decade age group. This information could be of practical usefulness in the clinical setting.
Aged ; Alzheimer Disease* ; Atrophy* ; Cognition Disorders ; Dementia* ; Diagnosis ; Humans ; Korea* ; Pemetrexed ; ROC Curve

BACKGROUND: This study was to investigate the effect of biomechanical stimulation on osteoblast differentiation of human periosteal-derived stem cell using the newly developed bioreactor. METHODS: Human periosteal-derived stem cells were harvested from the mandible during the extraction of an impacted third molar. Using the new bioreactor, 4% cyclic equibiaxial tension force (0.5 Hz) was applied for 2 and 8 h on the stem cells and cultured for 3, 7, and 14 days on the osteogenic medium. Biochemical changes of the osteoblasts after the biomechanical stimulation were investigated. No treatment group was referred to as control group. RESULTS: Alkaline phosphatase (ALP) activity and ALP messenger RNA (mRNA) expression level were higher in the strain group than those in the control group. The osteocalcin and osteonectin mRNA expressions were higher in the strain group compared to those in the control group on days 7 and 14. The vascular endothelial growth factor (VEGF) mRNA expression was higher in the strain group in comparison to that in the control group. Concentration of alizarin red S corresponding to calcium content was higher in the strain group than in the control group. CONCLUSIONS: The study suggests that cyclic tension force could influence the osteoblast differentiation of periosteal-derived stem cells under optimal stimulation condition and the force could be applicable for tissue engineering.
Alkaline Phosphatase ; Bioreactors ; Calcium ; Humans* ; Jaw* ; Mandible ; Molar, Third ; Osteoblasts* ; Osteocalcin ; Osteonectin ; RNA, Messenger ; Stem Cells* ; Tissue Engineering ; Vascular Endothelial Growth Factor A

BACKGROUND: Body mass index (BMI) and waist circumference (WC) are associated with cardiovascular (CV) risk factors. The aim of this study was to investigate the correlation of CV risk factors by cross-tabulating central obesity with multiple BMI categories in Korea. METHODS: A total of 328,789 adults aged 30–84 years who completed health assessments for National Health Insurance in 2012–2013 in Korea were examined. The participants were divided into two WC and five BMI groups to investigate CV risk factors, including metabolic syndrome (MetS), hypertension, diabetes, and dyslipidemia. RESULTS: The proportions of central obesity and obesity were 24.2% and 39.5% in men and 19.4% and 28.1% in women, respectively, according to the Korean Society for the Study of Obesity and World Health Organization Asia-Pacific Guideline criteria. The odds ratios (ORs) of CV risk factors in all sexes increased with increases in BMI and WC. Compared to the group with a normal WC and BMI, the adjusted ORs (95% confidence intervals) for having MetS and diabetes in the centrally obese and highest BMI group (BMI ≥30.0 kg/m²) were 35.95 (33.75–38.30) and 3.51 (3.26–3.77) in men and 29.22 (27.36–31.20) and 4.35 (4.02–4.70) in women, respectively. Participants who were centrally obese and obese (BMI ≥25.0 kg/m²) had the strongest correlation with all CV risk factors compared with those who were not centrally obese or obese. CONCLUSION: The presence of central obesity in multiple BMI categories may significantly identify individuals at increased risk of CV risk factors.
Adult ; Body Mass Index* ; Cardiovascular Diseases ; Diabetes Mellitus ; Dyslipidemias ; Female ; Humans ; Hypertension ; Korea* ; Male ; National Health Programs ; Obesity ; Obesity, Abdominal* ; Odds Ratio ; Risk Factors* ; Waist Circumference ; World Health Organization

OBJECTIVE: To determine the optimal CT image reconstruction parameters for the measurement of early transmitral peak velocity (E), early peak mitral septal tissue velocity (E′), and E / E′. MATERIALS AND METHODS: Forty-six patients underwent simultaneous cardiac CT and echocardiography on the same day. Four CT datasets were reconstructed with a slice thickness/interval of 0.9/0.9 mm or 3/3 mm at 10 (10% RR-interval) or 20 (5% RR-interval) RR-intervals. The E was calculated by dividing the peak transmitral flow (mL/s) by the corresponding mitral valve area (cm²). E′ was calculated from the changes in the left ventricular length per cardiac phase. E / E′ was then estimated and compared with that from echocardiography. RESULTS: For assessment of E / E′, CT and echocardiography were more strongly correlated (p < 0.05) with a slice thickness of 0.9 mm and 5% RR-interval (r = 0.77) than with 3 mm or 10% RR-interval. The diagnostic accuracy of predicting elevated filling pressure (E / E′≥ 13, n = 14) was better with a slice thickness of 0.9 mm and 5% RR-interval (87.0%) than with 0.9 mm and 10% RR-interval (71.7%) (p = 0.123) and significantly higher than that with a slice thickness of 3 mm with 5% (67.4%) and 10% RR-interval (63.0%), (p < 0.05), respectively. CONCLUSION: Data reconstruction with a slice thickness of 0.9 mm at 5% RR-interval is superior to that with a slice thickness of 3 mm or 10% RR-interval in terms of the correlation of E / E′ between CT and echocardiography. Thin slices and frequent sampling also allow for more accurate prediction of elevated filling pressure.
Dataset ; Echocardiography* ; Heart Ventricles ; Humans ; Image Processing, Computer-Assisted ; Mitral Valve ; Ventricular Function