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An important educational goal is enabling students to learn scientific concepts. The scientific concepts learned in class are developed within students' cognitive structures. Despite the successful application of Semantic Network Analysis (SNA) to study these cognitive structures, there has been limited examination of students' concept networks based on their individual characteristics. Therefore, this study aims to evaluate the differences in students' characteristics based on their cognitive levels, which influence their thinking and behavior. To analyze these differences, this study compares concept and connected concept networks, focusing on photosynthesis, a challenging life sciences topic. The study's results indicate that students could not clearly distinguish concepts by subtopic, but there were changes in the concept network after class. Although the types and number of concepts students knew were similar depending on their cognitive level, the concept network structure differed. Additionally, some students could not distinguish between similar concepts. Thus, teachers are advised to differentiate between similar concepts during instruction and address personal variables such as students' cognitive levels.

If the concepts used in curriculum, textbooks, classroom teaching, and assessment are not consistent, students may have difficulty in understanding the concepts of science correctly and this may lead to the formation of misconceptions. The purpose of this study is to measure the alignment of science concepts by analyzing the semantic networks of curriculum, textbooks, classroom teaching, and student assessment with respect to the contents on meiosis as covered in Life Science I. The semantic network method using the NetMiner 4.0 program was applied. 11 concepts were extracted from the curriculum commentary. The textbook presented 36 concepts; classroom teaching presented 54 concepts; a total of 23 concepts were presented from assessment. With respect to alignment of relevant concepts, 6 (gamete, chromosome, meiosis, gene, daughter cell and cell division) were linked to all 4 sources (curriculum, textbooks, classroom teaching, and assessment). These concepts are mainly used to explain the process of meiosis. It is concluded that the key concepts of meiosis exhibited alignment in curriculums, textbooks, classroom teaching and assessment. However, there are many concepts used only in textbooks and classroom teaching. The greater number of concepts in textbooks and teaching can become one of the causes of a deficit in learning.

Teachers are highly reliant on textbooks for teaching. In the Republic of Korea, science textbooks help students to understand scientific terms through inquiry activities. However, there is a lack of analysis on whether the inquiry activities suggested in these textbooks appropriately cover the terms included in the main text. Therefore, this study assesses the life science units included in widely used lower secondary school science textbooks in the Republic of Korea by analysing the connection between the terms presented in the inquiry activities and the main text using the NetMiner 4.0 programme. The results reveal that the life science units included in the lower secondary school science textbooks are well structured for learning life science terms through the inquiry activities, as the terms presented in the inquiry activities and the main text are well connected. However, the number of terms included in each unit greatly differs and needs to be supplemented with the optimization of the number of terms per unit. The results provide basic data for the future development of lower secondary school science textbooks. Future research should analyse how the terms used in inquiry activities and the main text are connected in real science classes.

This study examined a network of concepts used in the curriculum, textbooks, instruction, and assessment in relation to somatic cell division and investigated the alignment of science concepts used in them. Textbooks and teachers' instruction and evaluation questions were collected to analyse the alignment between the concepts and the conceptual network used in the curriculum, textbooks, instruction, and assessment on the basis of the national science curriculum in the Republic of Korea. The findings of this study suggest that the concept of a cell was used as a linkage, and a lack of conceptual linkage prevailed between the curriculum, textbooks, instruction, and assessment in the somatic cell division unit. In comparison with the curriculum, a rapid increase in the number of concepts presented in classes led to a complicated conceptual network. As the conceptual network was complex and ambiguous, the concepts that students can learn are more likely to be ambiguous. Therefore, the conceptual network could be instrumental for facilitating students' conceptual understanding of somatic cell division. The alignment of concepts and conceptual linkage in the teaching of somatic cell division could contribute to improving conceptual associations between the curriculum, textbooks, instruction, and assessment.

The term "Energy Budget" represents the incoming solar energy, outgoing amounts of energy, and the energy retained in the Earth's atmosphere. This article aims to analyze the energy budget trend in the Korean Peninsula over the period from 2001 to 2022, focusing on the Earth's Energy Imbalance (EEI) and the role of cloud cover and how it influences shortwave (SW) and longwave (LW) radiation. Using the dataset obtained from NASA's CERES satellite, the article investigates the amount of reflected and emitted energy globally and compares it with the Korean peninsula. The findings indicate that globally, the total wave which is the sum of all longwave, shortwave, and cloud shortwave radiation has increased in trend. The plot also displays a decrease in Cloud fraction (CL fraction) or cloud coverage. Contrary to this, the Korean peninsula displayed a relatively stable level of total radiation and an increase in CL fraction. However, further analysis is needed to understand the factors behind these regional differences, including the potential influence of monsoon circulation patterns. [ABSTRACT FROM AUTHOR]

Objective We investigated the incidence of and risk factors for myelodysplastic syndrome (MDS) in patients with rheumatologic disease. Methods We conducted a retrospective cohort study of patients who were diagnosed with rheumatologic diseases at a tertiary care hospital between May 2009 and July 2022 and identified the patients who were subsequently diagnosed with MDS. Each patient with MDS was matched with five age- and sex-matched controls chosen from the cohort of patients with each specific rheumatologic disease. Results During a total follow-up of 55 841 person-years (PY), MDS occurred in 64 patients, yielding an incidence rate of 1.15/1000 PY {median age 57.0 years [interquartile range (IQR) 41.0–69.0], median duration to MDS diagnosis 6.5 years (IQR 3.0–9.0)]. In an age-matched analysis, SLE was a significant risk factor for MDS [adjusted hazard ratio 2.61 (CI 1.19, 36.06), P  = 0.01]. Refractory cytopenia with multilineage dysplasia was the most common phenotype of MDS (35.9%), and more than half of the patients had karyotypes with a favourable prognosis (54.7%). Compared with matched controls, RA, SLE and AS patients with MDS had lower levels of haemoglobin at the time of diagnosis of rheumatologic disease. Furthermore, the MDS patients with SLE and Behçet's disease had higher levels of glucocorticoid use in terms of frequency of use and mean dose than control patients. Conclusion SLE is a significant risk factor for MDS among patients with rheumatologic diseases. A lower haemoglobin level at the time of diagnosis of rheumatologic disease was associated with the future development of MDS. [ABSTRACT FROM AUTHOR]

Background: Due to the increasing proportion of older adults in Korea and growing interest in aging, the concepts of oral aging and oral hypofunction have recently been introduced. Thus, it is necessary to investigate the age-specific oral function levels of Korean older adults and develop expert intervention methods for healthy aging. Methods: Dysphagia, independence of daily living, and oral hypofunction were assessed in 206 older adults living in Wonju, Gangwon State, South Korea. Subjective dysphagia was assessed through self-report questionnaires using the Dysphagia Handicap Index (DHI), the Korean version of Eating Assessment Tool-10, and the Korean version of the Modified Barthel Index. In addition, the oral hypofunction assessment items included decreased chewing ability, occlusal pressure, tongue pressure, oral dryness, and oral cleanliness. Results: DHI increased significantly with age, with those in their 80 s reporting the most difficulty swallowing. Oral function in terms of chewing ability (maximum occlusal pressure and number of remaining teeth), maximum occlusal pressure, and maximum tongue pressure also declined with increasing age. While there was no significant difference in oral dryness by age, those in their 80 s had dry mouth according to the criteria of the oral moisture checking device. Conclusions: In an assessment of oral function in community-dwelling, independent Korean older adults, the number of items that were assessed as oral hypofunction increased with age. The findings can be used to standardize the oral hypofunction assessment item and develop age-based individualized intervention plans for the early management of oral health and individual oral myofunctional rehabilitation in Korean community-dwelling older adults. [ABSTRACT FROM AUTHOR]

Science inquiry activities carried out in a small group are learner-centered activities operating under the premise of collaborative interaction between members through various types of communication and consultation in the process of resolving issues. The changes in the types of interactions in the three exploratory activities targeting science-gifted students were analyzed using the Social Network Analysis (SNA). As a result of analyzing eight small groups, it was possible to divide the interaction types into two groups, namely, the alienation retaining type--where the type of interactions was retained from start to end--and the alienation changing type where the types of interactions changed. First, regarding active interactions between three members, the remaining students turned out to be alienated and could not participate in further inquiry activities. Second, changes of types occurred in accordance with the leaders' central positions. On the basis of this study, it is expected that future analyses will show how the type of interaction changes according to the level of inquiry or familiarity status with the inquiry topics. In addition, it is expected that studies about guidance and feedback of teachers and new students' participation in the interactions will follow.

Background: The residual life of a patient with human immunodeficiency virus (HIV) is of major interest to patients and their physicians. While existing analyses of HIV patient survival focus mostly on data collected at baseline, residual life analysis allows for dynamic analysis based on additional data collected over a period of time. As survival times typically exhibit a right-skewed distribution, the median provides a more useful summary of the underlying distribution than the mean. In this paper, we propose an efficient inference procedure that fits a semiparametric quantile regression model assessing the effect of longitudinal biomarkers on the residual life of HIV patients until the development of dyslipidemia, a disease becoming more prevalent among those with HIV. Methods: For estimation of model parameters, we propose an induced smoothing method that smooths nonsmooth estimating functions based on check functions. For variance estimation, we propose an efficient resampling-based estimator. The proposed estimators are theoretically justified. Simulation studies are used to evaluate their finite sample performances, including their prediction accuracy. We analyze the Korea HIV/AIDS cohort study data to examine the effects of CD4 (cluster of differentiation 4) cell count on the residual life of HIV patients to the onset of dyslipidemia. Results: The proposed estimator is shown to be consistent and normally distributed asymptotically. Under various simulation settings, our estimates are approximately unbiased. Their variances estimates are close to the empirical variances and their computational efficiency is superior to that of the nonsmooth counterparts. Two measures of prediction performance indicate that our method adequately reflects the dynamic character of longitudinal biomarkers and residual life. The analysis of the Korea HIV/AIDS cohort study data shows that CD4 cell count is positively associated with residual life to the onset of dyslipidemia but the effect is not statistically significant. Conclusions: Our method enables direct prediction of residual lifetimes with a dynamic feature that accommodates data accumulated at different times. Our estimator significantly improves computational efficiency in variance estimation compared to the existing nonsmooth estimator. Analysis of the HIV/AIDS cohort study data reveals dynamic effects of CD4 cell count on the residual life to the onset of dyslipidemia. [ABSTRACT FROM AUTHOR]

Cultivation of microorganisms such as fungi and bacteria is often not included in scientific inquiries conducted in school because of the difficulty of manufacturing a suitable medium. A method using dry rehydratable film to reduce the need to manufacture a suitable medium and shorten incubation time was developed as an efficient microbial testing method. Using this method, students can easily perform experiments on microorganisms in schools where time and space are limited. For example, we carried out an inquiry on the possibility of drinking refrigerated milk that is already past its expiration date. Through this activity, we could raise issues related to the current shelf-life labeling system implemented in Korea. In addition, the method can measure microorganisms in several ways through air, direct contact, and indirect contact, making the procedure easier to use in scientific activities at school.

The fungal strain KNUF-22-18B, belonging to Cucurbitariaceae, was discovered from a stink bug (Hygia lativentris) during the investigation of insect microbiota in Chungnam Province, South Korea. The colonies of the strain KNUF-22-18B were wooly floccose, white to brown in the center on oatmeal agar (OA), and the colonies were buff, margin even, and colorless, reverse white to yellowish toward the center on malt extract agar (MEA). The strain KNUF- 22-18B produced pycnidia after 60 days of culturing on potato dextrose agar, but pycnidia were not observed on OA. On the contrary, N. keratinophila CBS 121759T abundantly formed superficial pycnidia on OA and MEA after a few days. The strain KNUF-22-18B produced chlamydospores subglobose to globose, mainly in the chain, with a small diameter of 4.4-- 8.8 lm. At the same time, N. keratinophila CBS 121759T displayed a globose terminal with a diameter of 8--10 lm. A multilocus phylogeny using the internal transcribed spacer regions, 28S rDNA large subunit, b-tubulin, and RNA polymerase II large subunit genes further validated the uniqueness of the strain. The detailed description and illustration of the proposed species as Neocucurbitaria chlamydospora sp. nov. from Korea was strongly supported by molecular phylogeny. [ABSTRACT FROM AUTHOR]

Purpose: For the dignity of patients nearing the end of their lives, it is essential to provide end-of-life (EoL) care in a separate, dedicated space. This study investigated the utilization of specialized rooms for dying patients within a hospice unit. Methods: This retrospective study examined patients who died in a single hospice unit between January 1, 2017, and December 31, 2021. Utilizing medical records, we analyzed the circumstances surrounding death, the employment of specialized rooms for terminally ill patients, and the characteristics of those who received EoL care in a shared room. Results: During the 1,825-day survey period, deaths occurred on 632 days, and 799 patients died. Of these patients, 496 (62.1%) received EoL care in a dedicated room. The average duration of using this dedicated space was 1.08 days. Meanwhile, 188 patients (23.5%) died in a shared room. Logistic regression analysis revealed that a longer stay in the hospice unit was associated with a lower risk of receiving EoL care in a shared room (odds ratio [OR]=0.98, 95% confidence interval [CI] 0.97~0.99; P=0.002). Furthermore, a higher number of deaths on the day a patient died was associated with a greater risk of receiving EoL care in a shared room (OR=1.66, 95% CI 1.33~2.08; P＜0.001). Conclusion: To ensure that more patients receive EoL care for an adequate duration in a private setting, additional research is necessary to increase the number of dedicated rooms and incorporate them into the hospice unit at an early stage. [ABSTRACT FROM AUTHOR]

Objectives: A retrospective cohort study was conducted to evaluate the effects of combination oral contraceptives (COCs) on bone mineral density (BMD) and metabolism in perimenopausal Korean women. Methods: The study subjects comprised two groups. The COC group included 55 women who took low-dose COC for at least one year to control vasomotor symptoms. Another 55 women who had annual checkups without history of COC use served as controls. BMD and bone turnover markers were assessed periodically. Results: In the control group, 12-month BMD values at the lumbar spine (LS) and total hip (TH) significantly decreased with a greater magnitude at LS, and bone resorption (BR) and formation (BF) markers increased concurrently with a larger change in BR. COCs increased BMD at LS after 12 months and prevented BMD decline at TH. Multivariable linear regression revealed a significant difference in LS BMD between groups at 12 months. In the COC group, there were significant negative correlations between baseline BMD and Z-score at LS and corresponding changes at 12 months. COCs did not alter BR markers, whereas BF markers were significantly decreased at 3 months. Group comparison at 12 months, as tested with adjusted linear regression, disclosed significant differences in both BR and BF makers. Conclusions: Bone loss associated with activated bone turnover is evident during the menopausal transition, and COCs might prevent BMD decrease and suppress bone turnover markers in perimenopausal Korean women. Significant increase in LS BMD and decreases in BF makers suggest underlying mechanisms of greater impact on BF. [ABSTRACT FROM AUTHOR]

The fungal strain belonging to the genus Monochaetia of the family Sporocadaceae was isolated from hairy long-horned toad beetle (Moechotypa diphysis) during the screening of microfungi associated with insects from Gangwon Province, Korea. The strain KNUF-6L2F produced white, light brown to dirty black surface, and olivaceous green colonies with the higher growth, while the closest strain M. ilicis KUMCC 15-0520T were light brown to brown, and M. schimae SAUCC 212201T light brown to brown toward center. The strain KNUF-6L2F produced shorter (5.7-14.0 lm) apical appendages than M. ilicis (6.0-24.0 lm), but similar to M. schimae (7.0-12.5 lm). Three median cells of KNUF-6L2F were light brown to olivaceous green, whereas brown and olivaceous cells were observed from M. ilicis and M. schimae, respectively. And the strain KNUF-6L2F produced larger conidiogenous cells than M. ilicis and M. schimae. Additionally, phylogenetic analyses based on molecular datasets of internal transcribed spacer (ITS) regions, translation elongation factor 1-alpha (TEF1a), and b-tubulin (TUB2) genes corroborated the strain's originality. Thus, the strain is different from other known Monochaetia species, according to molecular phylogeny and morophology, hence we suggested the new species Monochaetia mediana sp. nov. and provided a descriptive illustration. [ABSTRACT FROM AUTHOR]

In this study, a fungal strain KNUF-22-025 belonging to the genus Botryotrichum was isolated from the soil in Korea. The cultural and morphological characteristics of this strain differed from those of closely related species. On malt extract agar, strain KNUF-22-025 showed slower growth than most of the related species, except B. domesticum. The conidia size (9.6-21.1 9.9-18.4 mm) of strain KNUF-22-025 was larger than those of B. piluliferum, B. domesticum, and B. peruvianum but smaller than those of B. atrogriseum and B. iranicum. Conidiophores in strain KNUF-22-025 (137 mm) were longer than those in other closely related species but shorter than those in B. atrogriseum. Multi-locus analysis of molecular markers, such as ITS, 28S ribosomal DNA, RBP2, and TUB2 revealed that strain KNUF-22-025 was distinct from other Botryotrichum species. Thus, this strain is proposed as a novel species based on morphological characteristics along with molecular phylogeny and named Botryotrichum luteum sp. nov. [ABSTRACT FROM AUTHOR]

In this study, fungal strains designated as KNUF-22-14A and KNUF-22-15A were isolated from soil samples in Korea. These two strains were identified based on cultural and morphological characteristics as well as phylogenetic analyses and were found to be morphologically and phylogenetically identical. Upon their morphological comparison with closely related species, such as Tolypocladium album, T. amazonense, T. endophyticum, T. pustulatum, and T. tropicale, a difference in the size of short phialides [0.6-2.4(-9.3) 0.8-1.4 mm] was observed. Meanwhile, these strains had larger conidia (1.2-3.0 1.2-3.0 mm) than T. album, T. amazonense, T. endophyticum, and T. tropicale and smaller conidia than T. pustulatum. Phylogenetic analyses using a multi-locus datasets based on ITS, LSU, and SSU showed that KNUF-22-14A and KNUF-22-15A formed a distinct cluster from previously identified Tolypocladium species. Thus, these fungal strains isolated from soil in Korea are proposed as a novel species according to their characteristics and are named Tolypocladium globosum sp. nov. [ABSTRACT FROM AUTHOR]

Objectives: The objectives of the study were to identify the differences in oral care methods between current and past hospitalizations and to investigate the need for inpatient oral care education for South Korean adults who have been hospitalized for more than 24 h. Methods: This study employed a cross‐sectional design. Between 23 December 2019 and 4 May 2020, a questionnaire was administered to 200 adult inpatients awaiting treatment and their guardians at university hospitals or clinics. Of these, the data of 195 patients were analysed. Frequency analysis, descriptive statistics and chi‐square tests were used for data analysis. Results: In daily life, the participants reported brushing their teeth thrice a day (52.3%) for 2 min (60%). A single product was the most used (51.3%). During hospitalization, 40% of the participants brushed their teeth thrice or more a day, 84.1% brushed for <1 min, and 83.6% did not use additional oral care products. Conclusions: Differences were observed between South Korean adults' oral care behaviours in daily life and those performed in hospitals. Oral hygiene habits, the frequency and duration of tooth brushing, and the use of oral care products decreased during hospitalization. Our findings can be applied to the development of oral care interventions for inpatients, while considering changes in the hospitalization environment and physical activity levels during hospitalization. [ABSTRACT FROM AUTHOR]

Objective There is little evidence for finding optimal antipsychotic treatment for schizophrenia, especially in paediatrics. To evaluate the performance and clinical benefit of several prediction methods for 1-year treatment continuation of antipsychotics. Design and Settings Population-based prognostic study conducting using the nationwide claims database in Korea. Participants 5109 patients aged 2-18 years who initiated antipsychotic treatment with risperidone/ aripiprazole for schizophrenia between 2010 and 2017 were identified. Main outcome measures We used the conventional logistic regression (LR) and common six machinelearning methods (least absolute shrinkage and selection operator, ridge, elstic net, randomforest, gradient boosting machine, and superlearner) to derive predictive models for treatment continuation of antipsychotics. The performance of models was assessed using the Brier score (BS), area under the receiver operating characteristic curve (AUROC) and area under the precision-recall curve (AUPRC). The clinical benefit of applying these models was also evaluated by comparing the treatment continuation rate between patients who received the recommended medication by models and patients who did not. Results The gradient boosting machine showed the best performance in predicting treatment continuation for risperidone (BS, 0.121; AUROC, 0.686; AUPRC, 0.269). Among aripiprazole models, GBM for BS (0.114), SuperLearner for AUROC (0.688) and random forest for AUPRC (0.317) showed the best performance. Although LR showed lower performance than machine learnings, the difference was negligible. Patients who received recommended medication by these models showed a 1.2-1.5 times higher treatment continuation rate than those who did not. Conclusions All prediction models showed similar performance in predicting the treatment continuation of antipsychotics. Application of prediction models might be helpful for evidence-based decision-making in antipsychotic treatment. [ABSTRACT FROM AUTHOR]

Aim: Subsequent cancers (SCs) after melanoma diagnosis further increases the risks of mortality and medical costs. This population‐based analysis aimed to evaluate risk factors for SC, mortality, and medical costs of melanoma patients with SC. Methods: A retrospective cohort analysis was conducted using a nationwide claims database during 2002‐2017 in South Korea. SC was defined as having other types of cancer diagnoses other than subsequent melanoma during‐up to 5 years after melanoma diagnosis. Melanoma patients were divided into patients with and without SC, and the overall and subgroup survival rates, the risk of developing SC, and the total medical costs were analyzed using a Kaplan–Meier method and regressions. Results: A total of 3740 melanoma patients were included in the analysis (mean age, 62.3 ± 15.4 y; 47.2% men), and 2273 patients (1157 within 2 months, 756 after 2 months of melanoma diagnosis) had SC. Higher Charlson comorbidity index score and male sex significantly increased the risk of developing SC. Five‐year survival rate and cumulative medical costs were 62.3% (95% confidence interval [CI], 60.8‐63.9) and $21,413, respectively, in all patients. Patients with SC diagnosed after 2 months showed the lowest survival rate of 47.8% (95% CI, 44.3‐51.4) and the highest costs of $27,081, showing a mortality hazard ratio of 1.65 (range, 1.46‐1.86) and a cost ratio of 1.189 (range, 1.112‐1.271) compared with those without SC. Conclusion: This study presented survival outcomes and medical costs in melanoma patients and confirmed that SC after the first diagnosis of melanoma significantly increased disease burden in terms of mortality and medical costs. [ABSTRACT FROM AUTHOR]

Background: We investigated cardiovascular disease (CVD), risk factors for CVD, and applicability of the three known CVD risk equations in the Korean human immunodeficiency virus/ Acquired Immune Deficiency Syndrome (HIV/AIDS) cohort. Materials and Methods: The study parcitipants were HIV-infected patients in a Korean HIV/ AIDS cohort enrolled from 19 hospitals between 2006 and 2017. Data collected at entry to the cohort were analyzed. The 5-year CVD risk in each participant was calculated using three CVD risk equations: reduced CVD prediction model of HIV-specific data collection on adverse effects of anti-HIV drugs (R-DAD), Framingham general CVD risk score (FRS), and Korean Coronary Heart Disease Risk Score (KRS). Results: CVD events were observed in 11 of 586 HIV-infected patients during a 5-year (median) follow-up period. The incidence of CVD was 4.11 per 1,000 person-years. Older age (64 vs. 41 years, P = 0.005) and diabetes mellitus (45.5% vs. 6.4%, P <0.001) were more frequent in patients with CVD. Using R-DAD, FRS, and KRS, 1.9%, 2.4%, and 0.7% of patients, respectively, were considered to have a very high risk (≥10%) of 5-year CVD. The discriminatory capacities of the three prediction models were good, with c-statistic values of 0.829 (P <0.001) for R-DAD, 0.824 (P <0.001) for FRS, and 0.850 (P = 0.001) for KRS. Conclusion: The FRS, R-DAD, and KRS performed well in the Korean HIV/AIDS cohort. A larger cohort and a longer period of follow-up may be necessary to demonstrate the risk factors and develop an independent CVD risk prediction model specific to Korean patients with HIV. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the effect of disease-modifying antirheumatic drugs (DMARDs) on diabetes mellitus (DM) development in rheumatoid arthritis (RA). Methods: This nested case–control study with a cohort of 69,779 DM-naïve adult patients with RA was conducted from 2011 to 2019 in South Korea. Cases with incident DM were identified and individually matched to randomly selected controls (1:4). DMARDs use was measured for 1 year before the index date and stratified by exposure duration. The association of each DMARD use with DM risk was estimated using conditional logistic regression adjusted for comorbidities and concomitant drug use. Results: Of the patients, 5.4% were newly diagnosed with DM. The use of statins and a higher cumulative dose of corticosteroids were associated with an increased DM risk. In a multivariable-adjusted analysis, cumulative duration of exposure (CDE) >270 days/year, hydroxychloroquine (HCQ; adjusted odds ratio [aOR], 0.76) and methotrexate (MTX; aOR, 0.81) were associated with a significant decrease in DM risk, and tacrolimus (TAC; aOR, 1.27) was associated with an increased risk. Conclusions: Long-term use of HCQ and MTX (>270 days/year) was associated with a reduction in DM incidence as opposed to TAC. [ABSTRACT FROM AUTHOR]

Although Apiospora Sacc. has previously been considered a sexual morph of Arthrinium species on the basis of phylogenetic, morphological, and ecological diagnoses, a recent study delimited these as different species. Recently, 14 species, including eight new species, of marine Arthrinium have been reported from Korea. Six known species have previously been renamed as species in the genus Apiospora (A. arundinis, A. marii, A. piptatheri, A. rasikravindrae, A. sacchari, and A. saccharicola). However, the eight new species of marine Arthrinium (Ar. agari, Ar. arctoscopi, Ar. fermenti, Ar. koreanum, Ar. marinum, Ar. pusillispermum, Ar. sargassi, and Ar. taeanense) are yet to be studied, and thus the taxonomic status of these species remains to be clarified. In this study, we conducted phylogenetic analyses using the internal transcribed spacer, 28S large subunit ribosomal RNA gene, translation elongation factor 1-alpha, and beta-tubulin regions to confirm the phylogenetic position of these eight species. Based on these analyses, we re-identified the eight Arthrinium species as new combinations in Apiospora. Additionally, among the six known Apiospora species, two (A. piptatheri and A. rasikravindrae) have not previously been recorded in Korea. On the basis of morphological and molecular analyses, we report these as new species in Korea. Herein, we present scanning electron micrographs detailing the morphologies of these species, along with phylogenetic trees and detailed descriptions. [ABSTRACT FROM AUTHOR]

Background: Although type 2 diabetes (T2D) remission after gastric cancer surgery has been reported, little is known about the predictors of postoperative T2D remission. Methods: This study used data from a nationwide cohort provided by the National Health Insurance Service in Korea. We developed a diabetes prediction (DP) score, which predicted postoperative T2D remissions using a logistic regression model based on preoperative variables. We applied machine-learning algorithms [random forest, XGboost, and least absolute shrinkage and selection operator (LASSO) regression] and compared their predictive performances with those of the DP score. Results: The DP score comprised five parameters: baseline body mass index (< 25 or ≥ 25 kg/m2), surgical procedures (subtotal or total gastrectomy), age (< 65 or ≥ 65 years), fasting plasma glucose levels (≤ 130 or > 130 mg/dL), and antidiabetic medications (combination therapy including sulfonylureas, combination therapy not including sulfonylureas, single sulfonylurea, or single non-sulfonylurea]). The DP score showed a clinically useful predictive performance for T2D remission at 3 years after surgery [training cohort: area under the receiver operating characteristics (AUROC) 0.73, 95% confidence interval (CI), 0.71–0.75; validation cohort: AUROC 0.72, 95% CI 0.69–0.75], which was comparable to that of the machine-learning models (random forest: AUROC 0.71, 95% CI 0.68–0.74; XGboost: AUROC 0.70, 95% CI 0.67–0.73; LASSO regression: AUROC 0.75, 95% CI 0.73–0.78 in the validation cohort). It also predicted the T2D remission at 6 and 9 years after surgery. Conclusions: The DP score is a useful scoring system for predicting T2D remission after gastric cancer surgery. [ABSTRACT FROM AUTHOR]

Background: Potential adverse effects might be caused by increasing the number of antipsychotic prescriptions. However, the empirical evidence regarding pediatric psychiatric patients is insufficient. Therefore, we explored the antipsychotic-induced adverse effects focusing on the neurological system. Method: Using the medical information of pediatric patients retrieved from the claims data of Health Insurance Review and Assessment in Korea, we identified those psychiatric patients who were started on antipsychotic treatment at age 2–18 years between 2010 and 2018 (n = 10,969). In this study, movement disorders and seizures were considered as major neurological adverse events. The extended Cox model with time-varying covariates was applied to explore the association between antipsychotic medication and adverse events. Findings: Total 1,894 and 1,267 cases of movement disorders and seizures occurred in 32,046 and 33,280 person-years, respectively. The hazard risks of neurological adverse events were 3–8 times higher in the exposed to antipsychotics period than in the non-exposure period. Among the exposure periods, the most dangerous period was within 30 days of cumulative exposure. High doses or polypharmacy of antipsychotics was associated with increased risks of neurological adverse events. Among individual antipsychotics, haloperidol showed the highest risk of developing movement disorders among the examined agents. Quetiapine showed a lower risk of developing movement disorders but a higher risk of developing seizures than risperidone. Conclusion: These findings suggest that antipsychotics should be used with caution in pediatric patients, especially regarding initial exposure, high dose, and polypharmacy. [ABSTRACT FROM AUTHOR]

Background: Anti-tumor necrosis factor (TNF) agents are increasingly used for rheumatic diseases and inflammatory bowel disease (IBD), but are associated with the development of anti-TNF-induced lupus (ATIL). Nonetheless, few ATIL studies on non-Caucasian IBD patients exist. Here, we investigated the incidence, clinical features, and risk factors of ATIL in Korea. Methods: We retrospectively reviewed the medical records of IBD patients undergoing anti-TNF therapy at our tertiary IBD center between 2008 and 2020. ATIL was diagnosed as a temporal association between symptoms and anti-TNF agents, and the presence of at least one serologic and non-serologic American College of Rheumatology criterion. The risk factors for ATIL occurrence were assessed using multivariate Cox regression analysis. Results: Of 1362 IBD patients treated with anti-TNF agents, 50 (3.7%) ATIL cases were suspected, of which 14 (1.0%) received a definitive diagnosis. Arthritis and mucocutaneous symptoms were observed in 13 and 4 patients, respectively. All ATIL cases were positive for anti-nuclear and anti-dsDNA antibodies. Four patients (30.8%) improved while continuing anti-TNF therapy. At the final follow up, the ATIL group (n = 14) had a lower IBD remission rate (30.8% versus 68.8%, p = 0.019) than the non-ATIL group (n = 36). Ulcerative colitis and longer disease duration were associated with ATIL occurrence, with hazard ratios of 7.017 (p = 0.005) and 1.118 (p = 0.002), respectively. Conclusion: Although rare, ATIL is associated with poor treatment response to IBD in Korean patients. ATIL should be considered if arthritis and mucocutaneous symptoms develop during anti-TNF therapy for IBD. [ABSTRACT FROM AUTHOR]

Antipsychotic drugs raise seizure risk in adults, and antipsychotic drug use is increasing among pediatric psychiatric disorder patients. However, few studies have examined seizure risk in this younger patient population. To evaluate seizure risk in pediatric patients on antipsychotics, we conducted a nested case–control study using a nationwide database. Patient information was retrieved from the Korean Health Insurance Review and Assessment (HIRA) database from 2008–2018. Antipsychotic use among newly diagnosed psychiatric patients was gathered starting 1 year before the index date and categorized as recent, past, consistent, or none. Seizure cases among these patients were defined based on (1) prescription of antiepileptic drugs or (2) an electroencephalography (EEG) examination among patients with seizure diagnostic code. A conditional logistic regression model was constructed to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for seizure risk due to antipsychotic use. In total, 1523 seizure cases and 6092 seizure-free controls aged 8–19 years with newly diagnosed psychiatric disorders were included for analysis. Logistic regression revealed a significant association between antipsychotic use and seizure development (recent users OR = 4.03, 95% CI 3.4–4.79; consistent users: OR = 2.84, 95% CI 2.44–3.3). Seizure risk enhanced further with an increase in the number of antipsychotic drugs used. Risperidone, aripiprazole, quetiapine, olanzapine, paliperidone, and blonanserin were independently associated with greater seizure risk. Pediatric patients receiving antipsychotics, especially new or multiple antipsychotic users, should be carefully monitored for seizure development. [ABSTRACT FROM AUTHOR]

Mongyudowŏndo, the single most influential Korean landscape painting from the Chosŏn dynasty, currently sits in the library of a private university in Tenri, Nara Prefecture, Japan. The painting, likely seized during the Japanese Invasion of Korea (1592-1598), is one of some 89,000 cultural objects of Korean origin currently located in Japan that have yet to be returned. This Comment examines the numerous legal barriers to restituting Korean cultural property from Japan. Part II addresses the guiding principles in the restitution of cultural property. It explains that existing international treaties are largely inadequate to oversee such cross-border disputes due to their signatory requirements, lack of self-execution and retroactivity. Part III examines the unique complications involved in bringing a claim in Japanese courts under domestic laws, such as title and heightened protection for nationally designated cultural properties. Accordingly, an alternate method of dispute resolution is required. In Part IV, I propose bilateral negotiations between Japan and South Korea and highlight factors that would contribute to a successful negotiation allowing South Korea to reclaim Mongyudowŏndo. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the cost-effectiveness of bariatric surgery (BS) compared to non-surgical treatment (NST) in Korean people with morbid obesity according to comorbidities and body mass index (BMI) severity. Methods: The target cohort was people with morbid obesity, defined as BMI of ≥ 35 kg/m2, or obese people with BMI of 30–34.9 kg/m2 having obesity-related comorbidities. A decision-tree model for 1-year obesity treatment and Markov model for the rest of life were used. In the decision-tree model, the comorbidity remission rate and BMI change after 1-year treatment were decided based on a prospective clinical trial. In the Markov model, the transition probabilities were calculated considering the BMI level and age. The starting age of 20 years, a cycle length of 1 year, a time horizon of 80 years, and a 5% discount rate were applied for the base case from the healthcare system perspective. Results: In the base case, BS improved quality-adjusted life years (QALYs) and was the cost-effective option in total cohort (incremental cost-effectiveness ratio of BS vs. NST was 674 USD/QALY). It was shown to be cost-effective in all subgroup analyses based on BMI level. In particular, BS was a dominant alternative for the subgroup with basal BMI of 35.0–37.4 kg/m2. Various sensitivity analyses showed the robustness of results indicating the cost-effectiveness of BS. Conclusion: BS at BMI of > 30 kg/m2 was more effective than NST for a reduction in BMI and remission of obesity-related comorbidities and was cost-effective in Korea. [ABSTRACT FROM AUTHOR]

Resident law was enacted to improve the training environment and working conditions. However, the law caused confusion in the field and resulted in a medical vacuum in inpatient care. It also resulted in a lack of training time. A hospitalist system was introduced to improve the quality of patient care and to cover the shortage of residents. This study aimed to outline a development strategy for hospitalists participation in resident education in Korea. The result of pilot study of the hospitalists in Korea showed that patients, nurses, and residents were satisfied with hospitalists. Eighty-five percent of surgical residents were helped in postoperative patient care and 70.7% of residents were willing to work with a hospitalist. The competency of surgical hospitalists includes understanding surgery and the appropriate management of postoperative complications. In order to shift the paradigm of resident education, the Korean government must pay the expenses for resident training. Through hospitalists' participation in the resident training, it may be possible to provide residents with more comprehensive and continuous education for inpatient care. [ABSTRACT FROM AUTHOR]

Background: Several studies have examined the risk and health outcomes related to polypharmacy among the elderly. However, information regarding polypharmacy among pediatric patients is lacking. Objective: The aim of this study was to investigate the prevalence of polypharmacy and its related factors among the pediatric population of South Korea. Methods: We used national claim data from the Health Insurance Review and Assessment Service—Pediatric Patients Sample (HIRA-PPS) in Korea originating from 2012 through 2016. Polypharmacy was defined as a daily average of two or more drugs used yearly. Complex chronic conditions (CCCs) were examined to evaluate concomitant chronic diseases in pediatric patients. Age-specific contraindications and potential drug-drug interactions were assessed according to criteria established by the Korea Institute of Drug Safety & Risk Management (KIDS). Descriptive statistics and logistic regression were conducted to analyze the status of polypharmacy and its associated risk factors in pediatric patients. Results: The 5-year prevalence of pediatric polypharmacy in pediatric patients was 3.7%. The prevalence of polypharmacy was much higher in younger pediatric patients: 9.5% for patients between the ages of 1–7 years, 0.9% for ages 6–11 years, and 1.1% for ages 12–19 years. Pediatric patients with CCCs, Medical Aid benefits, or a hospital admission history had a significantly higher prevalence of polypharmacy when compared to their counterparts without those conditions. The most commonly prescribed drugs were respiratory agents (29%) followed by anti-allergic drugs (18.7%), central nervous system agents (15.9%), antibiotics (10.1%), and gastrointestinal drugs (7.7%). There was a positive correlation between the daily average number of inappropriate prescriptions and the degree of polypharmacy, especially in pediatric patients between the ages of 1–7 years. Contraindications and potential drug-drug interactions occurred in 11.0% and 10.1% of patients exposed to polypharmacy, respectively. Conclusions: One in ten pediatric patients under the age of 7 years was prescribed two or more concurrent drugs on average per day. Furthermore, pediatric patients exposed to polypharmacy showed an increased risk of inappropriate drug use. The implementation of a medication review system that considers pediatric patient polypharmacy exposure would reduce inappropriate drug use and prevent unwanted adverse outcomes. [ABSTRACT FROM AUTHOR]

We evaluated the survival rates and medical expenditure in patients with lung cancer using a nationwide claims database in South Korea. A retrospective observational cohort study design was used, and 2,919 lung cancer patients and their matched controls were included. Medical expenditures were analyzed with the Kaplan-Meier sample average method, and patients were categorized into 4 groups by operation and primary treatment method (i.e. Patients with operation: OP = surgery, OP+CTx/RTx = surgery with anti-cancer drugs or radiotherapy; Patients without operation: CTx/RTx = anti-cancer drugs or radiotherapy, Supportive treatment). The 5-year medical expenditure per case was highest in the OP+CTx/RTx group ($36,013), followed by the CTx/RTx ($23,134), OP ($22,686), and supportive treatment group ($3,700). Lung cancer-related anti-cancer drug therapy was the major cost driver, with an average 53% share across all patients. Generalized linear regression revealed that monthly medical expenditure in lung cancer patients, after adjustment for follow-up month, was approximately 3.1–4.3 times higher than that in the control group (cost ratio for OP = 3.116, OP+CTx/RTx = 3.566, CTx/RTx = 4.340, supportive treatment = 4.157). The monthly medical expenditure at end of life was estimated at $2,139 for all decedents, and approximately a quarter of patients had received chemotherapy in the last 3 months. In conclusion, this study presented the quantified treatment costs of lung cancer on various aspects compared with matched controls according to the treatment of choice. In this study, patients with operation incurred lower lifetime treatment costs than patients with CTx/RTx or supportive treatment, indicating that the economic burden of lung cancer was affected by treatment method. Further studies including both cancer stage and treatment modality are needed to confirm these results and to provide more information on the economic burden according to disease severity. [ABSTRACT FROM AUTHOR]

• Less than 10% of RA patients experienced grade 3 neutropenia with tocilizumab treatment. • Previous history of neutropenia during csDMARD was a risk factor for tocilizumab-related neutropenia. • Age and extra-articular manifestations, but not neutropenia, were infection risk factors during tocilizumab treatment. To determine the risks and clinical significance of tocilizumab (TCZ)-related neutropenia, in real-world settings, for patients with rheumatoid arthritis (RA). Medical records of RA patients treated with TCZ at a tertiary referral hospital in South Korea were collected. Infectious complications were defined as cases confirmed by clinical diagnosis and treated with antibiotics. A total of 277 RA patients with TCZ treatment (intravenous: 152 [54.9%], subcutaneous: 125 [45.1%]) were included in our study. During the observational period, 22 (7%) patients experienced grade 3 neutropenia. No patients discontinued TCZ due to neutropenia, while the dosage of conventional synthetic DMARD (csDMARD) was either reduced or discontinued for 8 patients. Patients, who experienced neutropenia while using csDMARD, had a higher risk for grade 3/4 neutropenia during TCZ treatment (hazard ratio [HR]: 3.120, 95% CI: 1.189–8.189, P = 0.021). Among infections, pulmonary infections were the most common (10.35 per 100 patient-years). Age over 60 years (HR: 2.133, 95% CI: 1.118–4.071, P = 0.022) and the presence of extra-articular manifestations (adjusted HR: 11.096, 95% CI: 5.353–22.999, P < 0.001), but not neutropenia (adjusted HR: 1.263, 95% CI: 0.269–5.945, P = 0.77), were risk factors for infections during TCZ treatment. Approximately 7% of RA patients treated with TCZ developed grade 3 neutropenia. The previous history of neutropenia during csDMARD was a risk factor for TCZ-related neutropenia. Age and extra-articular manifestations, but not neutropenia, were risk factors for infection during TCZ treatment, suggesting that TCZ treatment can be maintained in the presence of neutropenia unless infection occurs. [ABSTRACT FROM AUTHOR]

The article presents the study which compared the retear pattern of the arthroscopic single-row technique (SRT), conventional suture-bridge technique (SBT), and knotless suture-bridge technique (K-SBT) to treat rotator cuff tears in the knee. The classifications of retear include type 1 (unhealed tendons) and type 2 (medially ruptured tendons with a healed footprint). Based on the results, SRT and K-SBT have different retear pattern than SBT.

The article compares the clinical and radiological outcomes of high-grade partial-thickness rotator cuff tears treated with arthroscopic conversion to full-thickness tears, followed by repair. It shows that the arthroscopic repair of partial-thickness bursal-side tears resulted in comparable or superior postoperative functional outcomes compared with that of articular-side tears. It also indicates that the postoperative retear rate did not differ significantly between the two groups.

The article discusses a study aimed to determine the repair integrity and clinical outcomes of 3 suture bridge (SB) repair methods including single mattress (SM), double pulley (DP) and double mattress (DM). The results showed that arthroscopic rotator cuff repair produced successful functional results and no major differences among SM-SB, DP-SB, and DM-SB procedures were observed. The results showed that there were no major differences in repair integrity between the 3 procedures postoperatively.

Background: It is essential to have information on the disease burden of lung cancer at an individual level throughout the life; however, few such results have been reported. Thus, this study aimed to assess the lifetime disease burden in patients with lung cancer by assessing various factors, such as survival, years of life lost (YLL) and medical expenditure in South Korea based on real-world data and extrapolation.Methods: Newly diagnosed lung cancer patients (n = 2919) in 2004-2010 were selected and observed until the end of 2015 using nationwide reimbursement claim database. The patients were categorised into the Surgery group, Chemo and/or Radiotherapy group (CTx/RTx), and Surgery+CTx/RTx according to their treatment modality. Age- and sex-matched control subjects were selected from among general population using the life table. The survival and cost data after diagnosis were analysed by a semi-parametric method, the Kaplan-Meier analysis for the first 100 months and rolling extrapolation algorithm for 101-300 months. YLL were derived from the difference in survival between patients and controls.Results: Lifetime estimates (standard error) were 4.5 (0.2) years for patients and 14.5 (0.1) years for controls and the derived YLL duration was 10.0 (0.2) years. Lifetime survival years showed the following trend: Surgery (14.2 years) > Surgery+CTx/RTx (8.5 years) > CTx/RTx group (3.0 years), and YLL were increased as lifetime survival years decreased (2.3, 8.7, 12.2 years, respectively). The mean lifetime medical cost was estimated at 30,857 USD/patient. Patients in the Surgery group paid higher treatment cost in first year after diagnosis, but the overall mean cost per year was lower at 4359 USD compared with 7075USD of Surgery+CTx/RTx or 7626USD of CTx/RTx group.Conclusions: Lung cancer has resulted in about 10 years of life lost in overall patients. The losses were associated with treatment modality, and the results indicated that diagnosing lung cancer in patients with low stage disease eligible for surgery is beneficial for reducing disease burden in terms of survival and treatment cost per year throughout the life. [ABSTRACT FROM AUTHOR]

Nylon, known for its outstanding physical properties, durability, and affordability, is in high demand across various industries. The majority of nylon is currently produced using petroleum-based raw materials, which causes negative environmental impacts such as greenhouse gas emission and fossil resource depletion. This has motivated research and development of eco-friendly production methods using biomass, we propose the environmental feasibility of kenaf-based nylon production strategy in the Republic of Korea. This study carries out a life cycle assessment (LCA) for analyzing the global warming potential (GWP) and fossil resource scarcity (FRS) of nylon 6,6 production from gamma-valerolactone (GVL) derived from kenaf. The life cycle inventory is analyzed based on the simulation data of the GVL-to-nylon 6,6 process and the two major environmental impacts are quantified when the biorefinery is operated at the Saemangeum agro-bio industrial cluster in Jeollabuk-do in Republic of Korea. The nylon 6,6 production in the Saemangeum can effectively reduce the GWP (61%) and FRS (67%) compared to the conventional nylon 6,6 production. Furthermore, if the GWP of the two materials used in the production of nylon 6,6 (HMDA, NaOH) can be reduced by 50%, the GWP per kilogram of nylon 6,6 produced will be reduced by 43% (1.91 kg CO 2 eq.). [Display omitted] • A 'greener' process for transformation of gamma-valerolactone derived from kenaf to Nylon 6,6 is studied. • The LCA is conducted to quantify the environmental impacts of nylon 6,6 production. • The green Nylon 6,6 reduces 61 % of CO 2 emission compared to the conventional nylon. [ABSTRACT FROM AUTHOR]