Background: Group B Streptococcus (GBS) is one of the leading causes of neonatal earlyonset sepsis, resulting in high mortality and significant comorbidity. Intrapartum penicillin prophylaxis is recommended for pregnant women with GBS colonization to prevent vertical transmission. For pregnant women at high risk of anaphylaxis to penicillin, clindamycin is recommended only if the susceptibility of GBS isolates has been identified. We retrospectively examined the GBS detection rate and clindamycin resistance among Korean women of reproductive age over the last 20 years. Methods: Microbiologic studies using vaginal, vaginal–rectal or vaginal–perianal swabs from female patients 15–49 years of age during 2003–2022 were reviewed. Annual GBS detection rates and clindamycin resistance rates were calculated. The study period was divided into two periods (period 1, 2003–2015; period 2, 2016–2022) based on the introduction of universal culture-based GBS screening in our center in 2016. GBS detection rates and clindamycin resistance rates were compared between the periods using χ2 tests. Results: A total of 14,571 women were tested 16,879 times and GBS was isolated in 1,054 tests (6.2%), with 423 clindamycin-resistant isolates (40.1%). The GBS detection rate increased from 3.4% (301/8,869) in period 1 to 9.4% (2,753/8,010) in period 2 (P < 0.001). Even during period 1, the GBS detection rate was higher in 2009–2015 compared to 2003–2008 (P < 0.001). Clindamycin resistance rates have remained at similar levels since 2009, which were 39.5% (199/301) in period 1 and 40.2% (303/753) in period 2 (P = 0.833). Conclusion This study demonstrated that GBS detection rates in Korean women of reproductive age significantly increased almost three times during the twenty years of the study period, with a persistently high clindamycin resistance rate of up to 40%.

Objective: The Huntington’s Disease Quality of Life Battery for Carers (HDQoL-C) is used to evaluate caregiver quality of life. This study aimed to develop and validate the Korean version of the HDQoL-C (K-HDQoL-C) to assess the burden on Korean caregivers of Huntington’s disease (HD) patients. Methods: A total of 19 HD caregivers (7 females, mean age 55.4±14.6 years) participated in this study. The K-HDQoL-C, a translation of the English version, consisted of demographic information, caring aspects, life satisfaction, and feelings about life. It was administered twice, 2 weeks apart. Internal consistency was evaluated using Cronbach’s α, and test-retest reliability was assessed with intraclass correlation coefficients. The relationship with the Zarit Burden Interview-12 (ZBI-12) was analyzed. Results: The internal consistencies of the K-HDQoL-C were 0.771 (part 2), 0.938 (part 3), and 0.891 (part 4). The test-retest reliability ranged from 0.908 to 0.936. Part 3 was negatively correlated with the ZBI-12, and part 4 was positively correlated with the ZBI-12 (r=-0.780, 0.923; p<0.001). Conclusion The K-HDQoL-C effectively evaluates the challenges faced by HD caregivers, particularly in terms of care aspects and life satisfaction.

Objectives: Excessive sedentary behavior in youth is a major global issue, contributing to the rise in childhood obesity and metabolic diseases. International public health authorities have issued guidelines recommending that children and adolescents limit their daily sedentary time, including screen time. However, to date, no studies have explored the relationship between sedentary behavior as an exposure factor and skeletal muscle strength and mass as outcomes in this population. The present study investigated the association of sedentary behavior with handgrip strength (HGS) and appendicular lean mass (ALM) among United States adolescents. Methods: A total of 1449 adolescent participants from the National Health and Nutrition Examination Survey (2011-2014) were included. Information on sedentary behavior, specifically daily sedentary time, was obtained through a self-reported questionnaire. Muscular parameters, including HGS and ALM, were measured. To adjust for differences in body size, these parameters were divided by body mass index (BMI) and weight. Linear regression analyses were performed to evaluate the associations between daily sedentary time and each muscular parameter, adjusting for age, sex, ethnicity, annual family income, and moderate-to-vigorous physical activity (MVPA). Results: The linear regression analyses revealed negative associations between daily sedentary time and all muscular parameters, apart from absolute ALM. These included HGS (β, -0.265; standard error [SE], 0.074; p=0.001), HGS/BMI (β, -0.021; SE, 0.004; p<0.001), HGS/weight (β, -0.008; SE, 0.002; p<0.001), ALM/BMI (β, -0.008; SE, 0.003; p=0.010), and ALM/weight (β, -0.003; SE, 0.001; p=0.005). Conclusions After adjusting for MVPA, daily sedentary time was inversely associated with HGS, HGS/BMI, HGS/weight, ALM/BMI, and ALM/weight in United States adolescents.

Purpose: To investigate whether a new phospholipid-releasing soft contact lens can improve symptoms of dry eyes. Methods: The study used 2.5-3.0 kg New Zealand rabbits including both normal non-dry eye rabbits and dry eye rabbits, the latter having undergone electrocauterization of the meibomian glands to block the gland orifices. Each rabbit wore a control contact lens on one eye and a phospholipid-releasing contact lens on the other eye daily. Phospholipid-releasing and control contact lenses were provided by NEOVISION Co., Ltd. The parameters assessed included tear film break-up time, tear osmolarity, ocular surface staining, and central corneal thickness. After the experiment, the rabbits were euthanized and their conjunctival tissue was stained with Periodic Acid Schiff (PAS) to observe conjunctival goblet cells. Results: In both dry eye and normal non-dry eye rabbits, tear film break-up time was longer and tear osmolarity was lower when using the phospholipid-releasing contact lens compared to the control contact lens. The ocular surface remained unstained in normal non-dry eye rabbits while staining was observed in dry eye rabbits. There was no significant difference in central corneal thickness between the control and phospholipid-releasing contact lenses in either group. PAS staining showed no difference in conjunctival goblet cell density between the two lens types in normal non-dry eye rabbits. However, in dry eye rabbits, the conjunctival goblet cell density tended to be slightly higher with the phospholipid-releasing contact lens compared to the control lens. Conclusions Phospholipid-releasing contact lenses may help reduce dry eye symptoms and minimize contact lens-related complications by stabilizing the tear film and lowering tear osmolarity.

Background: and Purpose: This clinical practice guideline provides evidence-based recommendations for treatment of dementia, focusing on cholinesterase inhibitors and N-methyl-D-aspartate (NMDA) receptor antagonists for Alzheimer’s disease (AD) and other types of dementia. Methods: Using the Population, Intervention, Comparison, Outcomes (PICO) framework, we developed key clinical questions and conducted systematic literature reviews. A multidisciplinary panel of experts, organized by the Korean Dementia Association, evaluated randomized controlled trials and observational studies. Recommendations were graded for evidence quality and strength using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Results: Three main recommendations are presented: (1) For AD, cholinesterase inhibitors (donepezil, rivastigmine, galantamine) are strongly recommended for improving cognition and daily function based on moderate evidence; (2) Cholinesterase inhibitors are conditionally recommended for vascular dementia and Parkinson’s disease dementia, with a strong recommendation for Lewy body dementia; (3) For moderate to severe AD, NMDA receptor antagonist (memantine) is strongly recommended, demonstrating significant cognitive and functional improvements. Both drug classes showed favorable safety profiles with manageable side effects. Conclusions This guideline offers standardized, evidence-based pharmacologic recommendations for dementia management, with specific guidance on cholinesterase inhibitors and NMDA receptor antagonists. It aims to support clinical decision-making and improve patient outcomes in dementia care. Further updates will address emerging treatments, including amyloid-targeting therapies, to reflect advances in dementia management.

Background/Aims: The Korean guidelines for Helicobacter pylori treatment were revised in 2020, however, the extent of adherence to these guidelines in clinical practice remains unclear. Herein, we initiated a prospective, nationwide, multicenter registry study in 2021 to evaluate the current management of H.pylori infection in Korea. Methods: This interim report describes the adherence to the revised guidelines and their impact on firstline eradication rates. Data on patient demographics, diagnoses, treatments, and eradication outcomes were collected using a web-based electronic case report form. Results: A total of 7,261 patients from 66 hospitals who received first-line treatment were analyzed.The modified intention-to-treat eradication rate for first-line treatment was 81.0%, with 80.4% of the prescriptions adhering to the revised guidelines. The most commonly prescribed regimen was the 14-day clarithromycin-based triple therapy (CTT; 42.0%), followed by tailored therapy (TT; 21.2%), 7-day CTT (14.1%), and 10-day concomitant therapy (CT; 10.1%). Time-trend analysis demonstrated significant increases in guideline adherence and the use of 10-day CT and TT, along with a decrease in the use of 7-day CTT (all p<0.001). Multivariate logistic regression analysis revealed that guideline adherence was significantly associated with first-line eradication success (odds ratio, 2.03; 95% confidence interval, 1.61 to 2.56; p<0.001). Conclusions The revised guidelines for the treatment of H. pylori infection have been increasingly adopted in routine clinical practice in Korea, which may have contributed to improved first-line eradication rates. Notably, the 14-day CTT, 10-day CT, and TT regimens are emerging as the preferred first-line treatment options among Korean physicians.

Purpose: Cancer poses a significant global health challenge, demanding precise genomic testing for individualized treatment strategies. Targeted-panel sequencing (TPS) has improved personalized oncology but often lacks comprehensive coverage of crucial cancer alterations. Whole-genome sequencing (WGS) addresses this gap, offering extensive genomic testing. This study demonstrates the medical potential of WGS. Materials and Methods: This study evaluates target-enhanced WGS (TE-WGS), a clinical-grade WGS method sequencing both cancer and matched normal tissues. Forty-nine patients with various solid cancer types underwent both TE-WGS and TruSight Oncology 500 (TSO500), one of the mainstream TPS approaches. Results: TE-WGS detected all variants reported by TSO500 (100%, 498/498). A high correlation in variant allele fractions was observed between TE-WGS and TSO500 (r=0.978). Notably, 223 variants (44.8%) within the common set were discerned exclusively by TE-WGS in peripheral blood, suggesting their germline origin. Conversely, the remaining subset of 275 variants (55.2%) were not detected in peripheral blood using the TE-WGS, signifying them as bona fide somatic variants. Further, TE-WGS provided accurate copy number profiles, fusion genes, microsatellite instability, and homologous recombination deficiency scores, which were essential for clinical decision-making. Conclusion TE-WGS is a comprehensive approach in personalized oncology, matching TSO500’s key biomarker detection capabilities. It uniquely identifies germline variants and genomic instability markers, offering additional clinical actions. Its adaptability and cost-effectiveness underscore its clinical utility, making TE-WGS a valuable tool in personalized cancer treatment.

Purpose: The association between the fecal microbiota and colorectal cancer (CRC) risk has been suggested in epidemiologic studies. However, data from large-scale population-based studies are lacking. Materials and Methods: In this case-control study, we recruited 283 CRC patients from the Center for Colorectal Cancer, National Cancer Center Hospital, Korea to perform 16S rRNA gene sequencing of fecal samples. A total of 283 age- and sex-matched healthy participants were selected from 890 cohort of healthy Koreans that are publicly available (PRJEB33905). The microbial dysbiosis index (MDI) was calculated based on the differentially abundant species. The association between MDI and CRC risk was observed using conditional logistic regression. Sparse Canonical Correlation Analysis was performed to integrate species data with microbial pathways obtained by PICRUSt2. Results: There is a significant divergence of the microbial composition between CRC patients and controls (permutational multivariate analysis of variance p=0.001). Those who were in third tertile of the MDI showed a significantly increased risk of CRC in the total population (odds ratio [OR], 6.93; 95% confidence interval [CI], 3.98 to 12.06; p-trend < 0.001) compared to those in the lowest tertile. Similar results were found for men (OR, 6.28; 95% CI, 3.04 to 12.98; p-trend < 0.001) and women (OR, 7.39; 95% CI, 3.10 to 17.63; p-trend < 0.001). Bacteroides coprocola and Bacteroides plebeius species and 12 metabolic pathways were interrelated in healthy controls that explain 91% covariation across samples. Conclusion Dysbiosis in the fecal microbiota may be associated with an increased risk of CRC. Due to the potentially modifiable nature of the gut microbiota, our findings may have implications for CRC prevention among Koreans.

Purpose: This study aimed to develop a magnetic resonance imaging (MRI)–based radiomics model to predict high-risk pathologic features for lung adenocarcinoma: micropapillary and solid pattern (MPsol), spread through air space, and poorly differentiated patterns. Materials and Methods: As a prospective study, we screened clinical N0 lung cancer patients who were surgical candidates and had undergone both 18F-fluorodeoxyglucose (FDG) positron emission tomography–computed tomography (PET/CT) and chest CT from August 2018 to January 2020. We recruited patients meeting our proposed imaging criteria indicating high-risk, that is, poorer prognosis of lung adenocarcinoma, using CT and FDG PET/CT. If possible, these patients underwent an MRI examination from which we extracted 77 radiomics features from T1-contrast-enhanced and T2-weighted images. Additionally, patient demographics, maximum standardized uptake value on FDG PET/CT, and the mean apparent diffusion coefficient value on diffusion-weighted image, were considered together to build prediction models for high-risk pathologic features. Results: Among 616 patients, 72 patients met the imaging criteria for high-risk lung cancer and underwent lung MRI. The magnetic resonance (MR)–eligible group showed a higher prevalence of nodal upstaging (29.2% vs. 4.2%, p < 0.001), vascular invasion (6.5% vs. 2.1%, p=0.011), high-grade pathologic features (p < 0.001), worse 4-year disease-free survival (p < 0.001) compared with non-MR-eligible group. The prediction power for MR-based radiomics model predicting high-risk pathologic features was good, with mean area under the receiver operating curve (AUC) value measuring 0.751-0.886 in test sets. Adding clinical variables increased the predictive performance for MPsol and the poorly differentiated pattern using the 2021 grading system (AUC, 0.860 and 0.907, respectively). Conclusion Our imaging criteria can effectively screen high-risk lung cancer patients and predict high-risk pathologic features by our MR-based prediction model using radiomics.

Background: Group B Streptococcus (GBS) is one of the leading causes of neonatal earlyonset sepsis, resulting in high mortality and significant comorbidity. Intrapartum penicillin prophylaxis is recommended for pregnant women with GBS colonization to prevent vertical transmission. For pregnant women at high risk of anaphylaxis to penicillin, clindamycin is recommended only if the susceptibility of GBS isolates has been identified. We retrospectively examined the GBS detection rate and clindamycin resistance among Korean women of reproductive age over the last 20 years. Methods: Microbiologic studies using vaginal, vaginal–rectal or vaginal–perianal swabs from female patients 15–49 years of age during 2003–2022 were reviewed. Annual GBS detection rates and clindamycin resistance rates were calculated. The study period was divided into two periods (period 1, 2003–2015; period 2, 2016–2022) based on the introduction of universal culture-based GBS screening in our center in 2016. GBS detection rates and clindamycin resistance rates were compared between the periods using χ2 tests. Results: A total of 14,571 women were tested 16,879 times and GBS was isolated in 1,054 tests (6.2%), with 423 clindamycin-resistant isolates (40.1%). The GBS detection rate increased from 3.4% (301/8,869) in period 1 to 9.4% (2,753/8,010) in period 2 (P < 0.001). Even during period 1, the GBS detection rate was higher in 2009–2015 compared to 2003–2008 (P < 0.001). Clindamycin resistance rates have remained at similar levels since 2009, which were 39.5% (199/301) in period 1 and 40.2% (303/753) in period 2 (P = 0.833). Conclusion This study demonstrated that GBS detection rates in Korean women of reproductive age significantly increased almost three times during the twenty years of the study period, with a persistently high clindamycin resistance rate of up to 40%.