This report presents the latest statistics on the stroke population in South Korea, sourced from the Clinical Research Collaborations for Stroke in Korea-National Institute for Health (CRCS-K-NIH), a comprehensive, nationwide, multicenter stroke registry. The Korean cohort, unlike western populations, shows a male-to-female ratio of 1.5, attributed to lower risk factors in Korean women. The average ages for men and women are 67 and 73 years, respectively.Hypertension is the most common risk factor (67%), consistent with global trends, but there is a higher prevalence of diabetes (35%) and smoking (21%). The prevalence of atrial fibrillation (19%) is lower than in western populations, suggesting effective prevention strategies in the general population. A high incidence of large artery atherosclerosis (38%) is observed, likely due to prevalent intracranial arterial disease in East Asians and advanced imaging techniques.There has been a decrease in intravenous thrombolysis rates, from 12% in 2017–2019 to 10% in 2021, with no improvements in door-to-needle and door-to-puncture times, worsened by the coronavirus disease 2019 pandemic. While the use of aspirin plus clopidogrel for noncardioembolic stroke and direct oral anticoagulants for atrial fibrillation is well-established, the application of direct oral anticoagulants for non-atrial fibrillation cardioembolic strokes in the acute phase requires further research. The incidence of early neurological deterioration (13%) and the cumulative incidence of recurrent stroke at 3 months (3%) align with global figures. Favorable outcomes at 3 months (63%) are comparable internationally, yet the lack of improvement in dependency at 3 months highlights the need for advancements in acute stroke care.

Purpose: Long-term oncologic differences in outcome between groups of patients with Lynch syndrome (LS) colorectal cancer (CRC) and sporadic CRC with microsatellite instability-high (MSI-H) are the focus of investigation in the current study. Methods: Patients registered in the Korean Hereditary Tumor Registry and 2 tertiary referral hospitals treated for stage I– III CRC between 2005 and 2015 were retrospectively analyzed. Detection for both groups was performed using pedigree, microsatellite instability, and mismatch repair (MMR) gene testing. Multivariate analyses for overall survival (OS) and disease-free survival (DFS) were conducted. Results: Cases of LS (n = 77) and sporadic CRC with MSI-H (n = 96) were identified. LS CRC patients were younger in age and displayed tumor sidedness, typically involving left-sided colon and rectum, compared to patients with sporadic CRC with MSI-H. OS and DFS were lower for LS CRC relative to CRC with MSI-H (OS, 72.7% vs. 93.8%, P = 0.001; DFS, 71.4% vs. 88.5%, P = 0.001). In multivariate analyses, tumor sidedness, stage, and chemotherapy were independent factors for OS and DFS. LS CRC was a prognostic factor for poorer OS (hazard ratio, 2.740; 95% confidence interval, 1.003–7.487; P = 0.049), but not DFS. Conclusion Our findings indicate that LS CRC is associated with poorer outcomes compared to sporadic CRC with MSI-H, presenting distinct clinical features. In view of the current lack of knowledge on genetic and molecular mechanisms, appropriate management taking into consideration the difficulty of identification of CRC with hypermutable tumors harboring heterogeneity is essential.

Purpose: Long-term oncologic differences in outcome between groups of patients with Lynch syndrome (LS) colorectal cancer (CRC) and sporadic CRC with microsatellite instability-high (MSI-H) are the focus of investigation in the current study. Methods: Patients registered in the Korean Hereditary Tumor Registry and 2 tertiary referral hospitals treated for stage I– III CRC between 2005 and 2015 were retrospectively analyzed. Detection for both groups was performed using pedigree, microsatellite instability, and mismatch repair (MMR) gene testing. Multivariate analyses for overall survival (OS) and disease-free survival (DFS) were conducted. Results: Cases of LS (n = 77) and sporadic CRC with MSI-H (n = 96) were identified. LS CRC patients were younger in age and displayed tumor sidedness, typically involving left-sided colon and rectum, compared to patients with sporadic CRC with MSI-H. OS and DFS were lower for LS CRC relative to CRC with MSI-H (OS, 72.7% vs. 93.8%, P = 0.001; DFS, 71.4% vs. 88.5%, P = 0.001). In multivariate analyses, tumor sidedness, stage, and chemotherapy were independent factors for OS and DFS. LS CRC was a prognostic factor for poorer OS (hazard ratio, 2.740; 95% confidence interval, 1.003–7.487; P = 0.049), but not DFS. Conclusion Our findings indicate that LS CRC is associated with poorer outcomes compared to sporadic CRC with MSI-H, presenting distinct clinical features. In view of the current lack of knowledge on genetic and molecular mechanisms, appropriate management taking into consideration the difficulty of identification of CRC with hypermutable tumors harboring heterogeneity is essential.

In vitro prediction of hepatotoxicity can enhance the performance of non-clinical animal testing for identifying chemical hazards. In this study, we assessed high-content analysis (HCA) using multi-parameter cell-based assays as an in vitro hepatotoxicity testing model using various hepatotoxicants and human hepatocytes such as HepG2 cells and human primary hepatocytes (hPHs). Both hepatocyte types were exposed separately to multiple doses of ten hepatotoxicants associated with liver injury whose mechanisms of action have been described. HCA data were obtained using fluorescence probes for nuclear size (Hoechst), mitochondrial membrane potential (TMRM), cytosolic free calcium (Fluo-4AM), and lipid peroxidation (BODIPY). Cellular alterations were observed in response to all hepatotoxicants tested. The most sensitive parameter was TMRM, with high sensitivity at a low dose, next was BODIPY, followed by Fluo-4AM. HCA data from HepG2 cells and hPHs were generally concordant, although some inconsistencies were noted. Both hepatocyte types showed mild or severe mitochondrial impairment and lipid peroxidation in response to several hepatotoxicants. The results demonstrate that the application of HCA to in vitro hepatotoxicity testing enables more efficient hazard identification, and further, they suggest that certain parameters could serve as sensitive endpoints for predicting the hepatotoxic potential of chemical compounds.
Animals ; Calcium ; Cytosol ; Fluorescence ; Hep G2 Cells ; Hepatocytes ; Humans ; In Vitro Techniques ; Lipid Peroxidation ; Liver ; Membrane Potential, Mitochondrial

With the increased use of cell therapy in the veterinary sector, there is a growing demand for the development of cell-based medicinal products and the determination of their safety. Currently, the Korean Animal and Plant Quarantine Agency has established a guideline for evaluating the safety of cell-based medicinal products for animal use. The guideline includes items related to definition, classification, management, manufacturing procedure and quality control (standard and test method), stability testing, toxicity testing, pharmacological testing, and performance of clinical trials. In addition, testing protocols related to safety assessment of animal cell-based products such as chromosome karyotyping, tumorigenicity testing, confirmatory testing of biodistribution and kinetics, and target animal safety testing are described in detail. Moreover, because cell-based medicinal products are novel therapies, deviations from traditional designs may be justified in order to obtain relevant safety information on the treatment. Additionally, this guideline can be amended on the basis of new scientific findings.
Animals ; Carcinogenicity Tests ; Cell- and Tissue-Based Therapy ; Classification ; Karyotyping ; Kinetics ; Plants ; Quality Control ; Quarantine ; Toxicity Tests

Acetylcholinesterase (AChE) activity level can be used as a diagnostic marker for anticholinesterase pesticide poisoning. In this study, we aimed to establish a baseline level of normal brain AChE activity in wild birds. AChE activity was measured in the brains of 87dead wild birds (26 species). The level of AChE activity ranged from 6.40 to 15.9 µmol/min/g of brain tissue in normal wild birds. However, the brain tissue AChE activity level in wild birds exposed to organophosphate (OP) pesticide was 48.0%–96.3% of that in the normal birds. These results may serve as reference values to facilitate routine diagnosis and monitoring of OP-poisoned wild birds.
Acetylcholinesterase ; Birds ; Brain ; Diagnosis ; Organophosphates ; Poisoning ; Reference Values

BACKGROUND: Patients who survive an acute phase of stroke are at risk of falls and fractures afterwards. However, it is largely unknown how frequent fractures occur in the Asian stroke population. METHODS: Patients with acute (< 7 days) ischemic stroke who were hospitalized between January 2011 and November 2013 were identified from a prospective multicenter stroke registry in Korea, and were linked to the National Health Insurance Service claim database. The incidences of fractures were investigated during the first 4 years after index stroke. The cumulative incidence functions (CIFs) were estimated by the Gray's test for competing risk data. Fine and Gray model for competing risk data was applied for exploring risk factors of post-stroke fractures. RESULTS: Among a total of 11,522 patients, 1,616 fracture events were identified: 712 spine fractures, 397 hip fractures and 714 other fractures. The CIFs of any fractures were 2.63% at 6 months, 4.43% at 1 year, 8.09% at 2 years and 13.00% at 4 years. Those of spine/hip fractures were 1.11%/0.61%, 1.88%/1.03%, 3.28%/1.86% and 5.79%/3.15%, respectively. Age by a 10-year increment (hazard ratio [HR], 1.23; 95% confidence interval [CI], 1.17–1.30), women (HR, 1.74; 95% CI, 1.54–1.97), previous fracture (HR, 1.72; 95% CI, 1.54–1.92) and osteoporosis (HR, 1.44; 95% CI, 1.27–1.63) were independent risk factors of post-stroke fracture. CONCLUSION: The CIFs of fractures are about 8% at 2 years and 13% at 4 years after acute ischemic stroke in Korea. Older age, women, pre-stroke fracture and osteoporosis raised the risk of post-stroke fractures.
Accidental Falls ; Asian Continental Ancestry Group ; Epidemiology ; Female ; Hip Fractures ; Humans ; Incidence ; Korea ; National Health Programs ; Osteoporosis ; Prospective Studies ; Risk Factors ; Spine ; Stroke

The number of persons infected by HIV/AIDS has consistently increased in Korea since the first case of HIV/AIDS infection in 1985 and reached 15,208 by 2016. About 1,100 new patients with HIV/ AIDS infections have emerged every year since 2013. In Korea, the Korea HIV/AIDS Cohort Study was established for the evidenced-based prevention, treatment, and effective management of patients infected with human immunodeficiency virus (HIV) in December 2006. This study monitored 1,438 patients, who accounted for about 10% of all patients with HIV/AIDS in Korea, for 10 years with the following aims: (1) to develop an administrative system for the establishment of a HIV/AIDS cohort-based study; (2) to standardize methodologies and the case report forms; and (3) to standardize multi-cohort data and develop a data cleaning method. This study aims to monitor at least 1,000 patients (excluding those for whom investigation had been completed) per year (estimated number of patients who can be monitored by January 2018: 939). By December 2016, the sex distribution was 93.3% for men, and 6.7% for women (gender ratio, 13.9:1.0), and 98.9% of all participants were Korean. More than 50.0% of the participants were confirmed as HIV positive after 2006. This study reports competitive, long-term research that aimed to develop policies for the prevention of chronic infectious diseases for patients with HIV. The data collected over the last decade will be used to develop indices for HIV treatment and health promotion.
Cohort Studies* ; Communicable Diseases ; Female ; Health Promotion ; HIV ; Humans ; Korea* ; Male ; Methods ; Sex Distribution ; Sexually Transmitted Diseases

The number of persons infected by HIV/AIDS has consistently increased in Korea since the first case of HIV/AIDS infection in 1985 and reached 15,208 by 2016. About 1,100 new patients with HIV/ AIDS infections have emerged every year since 2013. In Korea, the Korea HIV/AIDS Cohort Study was established for the evidenced-based prevention, treatment, and effective management of patients infected with human immunodeficiency virus (HIV) in December 2006. This study monitored 1,438 patients, who accounted for about 10% of all patients with HIV/AIDS in Korea, for 10 years with the following aims: (1) to develop an administrative system for the establishment of a HIV/AIDS cohort-based study; (2) to standardize methodologies and the case report forms; and (3) to standardize multi-cohort data and develop a data cleaning method. This study aims to monitor at least 1,000 patients (excluding those for whom investigation had been completed) per year (estimated number of patients who can be monitored by January 2018: 939). By December 2016, the sex distribution was 93.3% for men, and 6.7% for women (gender ratio, 13.9:1.0), and 98.9% of all participants were Korean. More than 50.0% of the participants were confirmed as HIV positive after 2006. This study reports competitive, long-term research that aimed to develop policies for the prevention of chronic infectious diseases for patients with HIV. The data collected over the last decade will be used to develop indices for HIV treatment and health promotion.
Cohort Studies ; Communicable Diseases ; Female ; Health Promotion ; HIV ; Humans ; Korea ; Male ; Methods ; Sex Distribution ; Sexually Transmitted Diseases

PURPOSE: The purpose of this retrospective study with 4–12 years of follow-up was to compare the marginal bone loss (MBL) between external-connection (EC) and internal-connection (IC) dental implants in posterior areas without periodontal or peri-implant disease on the adjacent teeth or implants. Additional factors influencing MBL were also evaluated. METHODS: This retrospective study was performed using dental records and radiographic data obtained from patients who had undergone dental implant treatment in the posterior area from March 2006 to March 2007. All the implants that were included had follow-up periods of more than 4 years after loading and satisfied the implant success criteria, without any peri-implant or periodontal disease on the adjacent implants or teeth. They were divided into 2 groups: EC and IC. Subgroup comparisons were conducted according to splinting and the use of cement in the restorations. A statistical analysis was performed using the Mann-Whitney U test for comparisons between 2 groups and the Kruskal-Wallis test for comparisons among more than 2 groups. RESULTS: A total of 355 implants in 170 patients (206 EC and 149 IC) fulfilled the inclusion criteria and were analyzed in this study. The mean MBL was 0.47 mm and 0.15 mm in the EC and IC implants, respectively, which was a statistically significant difference (P < 0.001). Comparisons according to splinting (MBL of single implants: 0.34 mm, MBL of splinted implants: 0.31 mm, P=0.676) and cement use (MBL of cemented implants: 0.27 mm, MBL of non-cemented implants: 0.35 mm, P=0.178) showed no statistically significant differences in MBL, regardless of the implant connection type. CONCLUSIONS: IC implants showed a more favorable bone response regarding MBL in posterior areas without peri-implantitis or periodontal disease.
Alveolar Bone Loss ; Dental Implant-Abutment Design ; Dental Implants ; Dental Records ; Follow-Up Studies ; Humans ; Peri-Implantitis ; Periodontal Diseases ; Retrospective Studies ; Splints ; Tooth