Objective: This study compared the incidence of suicide cases among Korean students before and after the coronavirus disease-2019 (COVID-19) pandemic. Methods: Aggregated case reports of all known suicide victims attending elementary, middle, and high school in South Korea from 2017 to 2022 were analyzed. These reports, compiled by teachers under the directive of the South Korean Department of Education, surveyed the circumstances surrounding each suicide and identified associated risk factors posthumously. Results: The completed suicide rate was 2.37 per 100,000 students pre-COVID-19 (2017–2019), significantly increasing to 3.37 per 100,000 students post-COVID-19 (2020–2022; odds ratio [OR] 1.42, p<0.001). The rate began to rise approximately 6 months into the pandemic and continued to worsen throughout 2021 and 2022. Fair attendance significantly increased in 2020 (74.83%, p=0.003) during the initial stage of school closure measures compared to 2019 (58.27%) among students prior to suicide completion. However, as social distancing measures continued, “absence due to medical reasons” showed a significant increase in 2022 (23.56%) compared to 2019 (13.67%, p=0.025) and 2020 (9.52%, p<0.001) among these students. Among those who completed suicide, teachers reported increased signs of depression and anxiety posthumously compared to pre-COVID-19 periods. Conclusion The incidence of completed suicide among students was significantly higher in the post-COVID-19 years compared to pre-COVID-19. Attendance records and teachers’ reports indicated a deterioration in mental health among these students before suicide completion, highlighting the need to consider mental health impacts when implementing future quarantine policies.

Tooth wear is a physiologic process, but when accelerated by specific factors, it is considered pathologic wear, leading various issues that require prosthodontic intervention. Full-mouth prosthetic rehabilitation is often considered to restore adequate vertical dimension and esthetics for patients with severely worn dentition.However, a minimally invasive prosthodontic approach through multidisciplinary collaboration may be feasible for patients with localized anterior or posterior wear. This clinical case addressed the treatment for excessive anterior deep bites and pathologic wear of the anterior teeth, leading to deteriorated esthetics and function. Orthodontic extrusion was employed in the posterior teeth to increase the vertical dimension of occlusion and secure adequate space for the anterior restorations. A minimally invasive treatment was possible by limiting the scope of treatment to the anterior region. As a result, function and esthetics were improved by restoring only the teeth with pathologic wear without removing healthy tooth structure.

With the increasing emphasis on diversity, equity, and inclusion (DEI) in organizations and institutions, academic societies in gastroenterology and hepatology are beginning to take actionable steps toward achieving DEI. The successful implementation of DEI initiatives leads to excellence in the field, improved patient outcomes, particularly in areas where health disparities are prevalent, and advances in the gastrointestinal discipline. Such implementation also results in a workforce that better reflects the growing diversity of the population. This review defines DEI and introduces the DEI policies and strategies adopted by the academic societies of gastroenterology in other countries. This paper proposes strategies to integrate DEI better into the Korean Society of Gastroenterology, emphasizing the importance of embedding DEI into the culture and strategic framework. The key strategies include establishing a DEI committee, setting clear targets, and conducting formal assessments to measure DEI progress. This study focused on enhancing workforce diversity, particularly among women and young doctors, and advocates for the need to support their academic development through male allyship and the promotion of equitable and inclusive academic cultures.

Background/Aims: The kidneys and retina are highly vascularized organs that frequently exhibit shared pathologies, with nephropathy often associated with retinopathy. Previous studies have successfully predicted estimated glomerular filtration rates (eGFRs) using fundus photographs. We evaluated the performance of the Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas in eGFR prediction. Methods: We enrolled patients with fundus photographs and corresponding creatinine measurements taken on the same date. One photograph per eye was randomly selected, resulting in a final dataset of 45,108 patients (88,260 photographs). Data including sex, age, and blood creatinine levels were collected for eGFR calculation using the MDRD and CKD-EPI formulas. EfficientNet B3 models were used to predict each parameter. Results: Deep neural network models accurately predicted age and sex using fundus photographs. Sex was identified as a confounding variable in creatinine prediction. The MDRD formula was more susceptible to this confounding effect than the CKD-EPI formula. Notably, the CKD-EPI formula demonstrated superior performance compared to the MDRD formula (area under the curve 0.864 vs. 0.802). Conclusions Fundus photographs are a valuable tool for screening renal function using deep neural network models, demonstrating the role of noninvasive imaging in medical diagnostics. However, these models are susceptible to the influence of sex, a potential confounding factor. The CKD-EPI formula, less susceptible to sex bias, is recommended to obtain more reliable results.

Neurosteroids play an important role as endogenous neuromodulators that are locally produced in the central nervous system and rapidly change the excitability of neurons and the activation of microglial cells and astrocytes. Here we review the mechanisms of synthesis, metabolism, and actions of neurosteroids in the central nervous system. Neurosteroids are able to play a variety of roles in the central nervous system under physiological conditions by binding to membrane ion channels and receptors such as gamma-aminobutyric acid type A receptors, Nmethyl-D-aspartate receptors, L- and T-type calcium channels, and sigma-1 receptors. In addition, numerous neurological disorders, including persistent neuropathic pain, multiple sclerosis, and seizures, have altered the levels of neurosteroids in the central nervous system. Thus, we review how local synthesis and metabolism of neurosteroids are modulated in the central nervous system and describe the role of neurosteroids under pathological conditions. Furthermore, we discuss whether neurosteroids may play a role as a new therapeutic for the treatment of neurological disorders.

Purpose: The impact of vitamin D deficiency on nonalcoholic fatty liver disease (NAFLD) risk in individuals without obesity or insulin resistance has not been thoroughly evaluated. We aimed to identify whether low serum levels of 25(OH)D independently contribute to NAFLD risk in nonobese or lean individuals. Materials and Methods: This study analyzed 241208 asymptomatic health check-up examinees who had abdominal ultrasonography. NAFLD risk was evaluated based on obesity status and serum 25(OH)D levels. Results: The overall NAFLD prevalence was 25.5%. Among the 178630 nonobese and 126909 lean participants, the prevalence rates were 13.4% and 6.7%, respectively. The multivariable adjusted odds ratios (ORs) [95% confidence intervals (CI)] for the prevalence of NAFLD, comparing serum 25(OH)D levels of 10–19 and ≥20 ng/mL with <10 ng/mL, were 0.96 (0.93–0.99) and 0.80 (0.77–0.83), respectively. Among nonobese participants, the corresponding adjusted ORs (95% CI) were 0.94 (0.90–0.99) and 0.77 (0.73–0.81), respectively. Similar results were observed among lean participants, with those having a 25(OH)D level of ≥20 ng/mL demonstrating a significantly lower odds of NAFLD (adjusted OR, 0.76; 95% CI, 0.70–0.83). Moreover, these results were consistent even among nonobese and lean individuals who showed no signs of insulin resistance. Conclusion Insufficient 25(OH)D levels independently increased the risk of NAFLD, suggesting its role in the NAFLD pathogenesis, regardless of obesity or insulin resistance status. Considering the established relationship between vitamin D deficiency and nonobese/lean NAFLD, maintaining adequate 25(OH)D levels may aid in preventing the development of NAFLD, even among nonobese or lean individuals.

Irritable bowel syndrome (IBS) is a chronic, disabling, and functional bowel disorder that significantly affects social functioning and reduces quality of life and increases social costs. The Korean Society of Neurogastroenterology and Motility published clinical practice guidelines on the management of IBS based on a systematic review of the literature in 2017, and planned to revise these guidelines in light of new evidence on the pathophysiology, diagnosis, and management of IBS. The current revised version of the guidelines is consistent with the previous version and targets adults diagnosed with or suspected of having IBS. These guidelines were developed using a combination of de novo and adaptation methods, with analyses of existing guidelines and discussions within the committee, leading to the identification of key clinical questions. Finally, the guidelines consisted of 22 recommendations, including 3 concerning the definition and risk factors of IBS, 4 regarding diagnostic modalities and strategies, 2 regarding general management, and 13 regarding medical treatment. For each statement, the advantages, disadvantages, and precautions were thoroughly detailed. The modified Delphi method was used to achieve expert consensus to adopt the core recommendations of the guidelines. These guidelines serve as a reference for clinicians (including primary care physicians, general healthcare providers, medical students, residents, and other healthcare professionals) and patients, helping them to make informed decisions regarding IBS management.

Background/Aims: We aim to compare the remission of erosive esophagitis (EE) among individuals with different phenotypes based on their metabolic health and obesity status and investigate the impact of changes in metabolic health on the EE remission. Methods: Asymptomatic adults (n = 16 845) with EE at baseline, who underwent follow-up esophagogastroduodenoscopy (EGD) were categorized into 4 groups as follows: metabolically healthy (MH) nonobese, metabolically unhealthy (MU) nonobese, MH obese, and MU obese. EE was defined as grade A or higher mucosal breaks observed using esophagogastroduodenoscopy. Results: During a median follow-up of 2.2 years, the remission rates of EE were 286.4/10 3 , 260.1/10 3 , 201.5/10 3 , and 219.9/10 3 person-years in MH nonobese, MU nonobese, MH obese, and MU obese groups, respectively. Multivariate-adjusted hazard ratios (95% CI) for EE remission among the MH nonobese, MU nonobese, and MH obese groups versus that of the MU obese group were 1.30 (1.23-1.37), 1.17 (1.12-1.23), and 0.98 (0.90-1.06), respectively, whereas those of the persistent MH, progression of MH to MU, and remission of MU to MH compared with the persistent MU group were 1.37 (1.23-1.52), 1.15 (1.01-1.30), and 1.28 (1.12-1.46), respectively.Increased EE remission in the persistent MH group was consistently observed in individuals with and without obesity (or abdominal obesity). Conclusions Metabolic health and nonobesity independently and favorably impact EE remission. Maintaining normal weight and healthy metabolic status may contribute to EE remission.

Purpose: Skeletal muscle atrophy, characterized by a reduction in muscle mass and size, is known to be associated with inflammation and oxidative stress. This study aimed to examine the effect of blackcurrant extract on tumor necrosis factor-alpha (TNF)-α-induced myotube atrophy. Methods: C2C12 myotubes were treated with blackcurrant extract and cultured with TNF-α for 24 hours. The myotubes were stained using May-Grunwald Giemsa staining to measure the myotube diameter. In addition, reactive oxygen species (ROS) levels were assessed.The mRNA expression of inflammation-related markers such as interleukin (IL)-6, IL-1β, cyclooxygenase-2 (COX-2), inducible NO synthase (iNOS), as well as mitochondria dynamicsrelated markers, including mitochondrial fission protein 1 (Fis1), optic atrophy 1 (Opa1) were measured by quantitative real-time polymerase chain reaction. The expression of muscle protein degradation markers, including muscle ring finger protein 1 (MuRF-1), atrogin-1, and forkhead box protein O3 (FoXO3), as well as mitochondrial biogenesis markers such as silent information regulator T1 (Sirt1) and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α), were assessed by western blot analysis. Results: Treatment with blackcurrant extract increased the myotube diameter, which was decreased in TNF-α-induced myotube atrophy. Treatment with TNF-α increased ROS levels and the expression of MuRF-1 and atrogin-1, and these increases were significantly inhibited by treatment with the blackcurrant extract. In contrast, the phosphorylation of FoXO3 was increased by the blackcurrant extract. Furthermore, the blackcurrant extract treatment decreased the mRNA expression of IL-6, IL-1β, COX-2, and iNOS elevated by TNF-α treatment. Additionally, blackcurrant extract treatment suppressed the expression of Fis1, while increasing the expression of Opa1, Sirt1, and PGC-1α. Conclusion These results suggest that blackcurrant extract reduces TNF-α-induced muscle protein degradation by the enhancement of mitochondrial biogenesis and mitochondrial dynamics. Thus, this study provides foundational data supporting the potential of blackcurrant extract as a functional ingredient for the prevention of muscle atrophy.

Background: Colorectal carcinomas (CRCs) with caudal-type homeobox 2 (CDX2) loss are recognized to pursue an aggressive behavior but tend to be accompanied by a high density of tumor-infiltrating lymphocytes (TILs). However, little is known about whether there is an interplay between CDX2 loss and TIL density in the survival of patients with CRC. Methods: Stage III CRC tissues were assessed for CDX2 loss using immunohistochemistry and analyzed for their densities of CD8 TILs in both intraepithelial (iTILs) and stromal areas using a machine learning-based analytic method. Results: CDX2 loss was significantly associated with a higher density of CD8 TILs in both intraepithelial and stromal areas. Both CDX2 loss and a high CD8 iTIL density were found to be prognostic parameters and showed hazard ratios of 2.314 (1.050–5.100) and 0.378 (0.175–0.817), respectively, for cancer-specific survival. A subset of CRCs with retained CDX2 expression and a high density of CD8 iTILs showed the best clinical outcome (hazard ratio of 0.138 [0.023–0.826]), whereas a subset with CDX2 loss and a high density of CD8 iTILs exhibited the worst clinical outcome (15.781 [3.939–63.230]). Conclusions Altogether, a high density of CD8 iTILs did not make a difference in the survival of patients with CRC with CDX2 loss. The combination of CDX2 expression and intraepithelial CD8 TIL density was an independent prognostic marker in adjuvant chemotherapy-treated patients with stage III CRC.