Sang-Hoon Kim’s research while affiliated with Rutgers New Jersey Medical School and other places

To explore the opportunity of expanding the page cache using disaggregated memory for file-backed pages, this study presents BalloonStasher, an RDMA-based disaggregated memory for data-intensive applications. Utilizing the ephemeral nature of the page cache, BalloonStasher dynamically adapts to the changing page cache demands of multiple clients. BalloonStasher supports one-sided RDMA-based memory pooling or two-sided RDMA-based memory sharing when using memory nodes. Additionally, it also supports peer memory mode, which utilizes the idle memory of peer nodes. Our extensive performance study compares the benefits and limitations of the three cache modes, and shows that BalloonStasher can mitigate the memory underutilization problem and improve performance of data-intensive applications by a large margin.

The effects of maternal exercise on hippocampal neurogenesis, synaptic protein expression, and gut microbiome composition in the offspring of older females were investigated. Male offspring from female C57BL/6 mice were divided into four groups: offspring of young female group (CON), offspring of exercised young female group, offspring of advanced-age female group (AMA), and offspring of exercised advanced-age female group (AMA+EX). The exercised group received 8 weeks of treadmill training before and during pregnancy. Male offspring were assessed at 4 weeks of age. Hippocampal neurogenesis was assessed by 5-bromo-2’-deoxyuridine/neuronal double immunofluorescence staining. Expression of synaptic plasticity-related proteins, including brain-derived neurotrophic factor (BDNF) and postsynaptic density protein 95 (PSD-95), was analyzed by Western blot. Gut microbiome composition and diversity were assessed using 16S rRNA sequencing of fecal samples. Offspring born to AMA females had significantly reduced hippocampal neurogenesis and lower expression levels of BDNF and PSD-95 compared to the CON group. In the AMA+EX group, maternal treadmill exercise significantly improved these deficits, restoring both neurogenesis and synaptic protein expression. In contrast, gut microbiota analysis showed that microbial richness and alpha diversity were reduced in the offspring of exercised females, despite the relatively high diversity in the CON and AMA groups, especially in the AMA+EX group. Older mothers impair hippocampal neurogenesis and synaptic protein expression in offspring, and alter gut microbial diversity. Maternal exercise may alleviate age-related neurodevelopmental disorders, but may also reduce microbial diversity in the offspring’s gut.

Increased exposure to particulate matter (PM) from air pollution causes lung inflammation and increases morbidity and mortality due to respiratory diseases. Pirfenidone is an anti-fibrotic agent used to treat idiopathic pulmonary fibrosis. Background/Objectives: In this experiment, we studied the therapeutic effects of pirfenidone on PM-induced pulmonary fibrosis. Methods: Pulmonary fibrosis was induced by the intratracheal application of 100 μg/kg PM10 mixed with 200 μL saline. After 42 days of PM10 infusion, 0.2 mL of distilled water with pirfenidone was orally administered to the pirfenidone-treated groups (200 and 400 mg/kg) every other day for a total of 15 times over 30 days. Results: The intratracheal administration of PM resulted in lung injury and a significant decrease in the number of bronchoalveolar lavage fluid cells. PM administration increased the lung injury score, level of lung fibrosis, and production of pro-inflammatory cytokines. Pirfenidone treatment effectively suppressed transforming growth factor-β-activated kinase 1 in PM-induced pulmonary fibrosis. The present changes inhibited the expressions of mitogen-activated protein kinase kinase 3 and p38, which suppressed transforming growth factor-β, ultimately alleviating lung fibrosis. PM exposure upregulated the expressions of fibronectin and type 1 collagen. PM exposure enhanced connective tissue growth factor and hydroxyproline levels in the lung tissue. The levels of these fibrosis-related factors were inhibited by pirfenidone treatment. Conclusions: These results suggest that pirfenidone is therapeutically effective against PM-induced pulmonary fibrosis.

Background Coronary artery disease (CAD) outcomes are influenced by social determinants, including marital status. However, research on the sex-specific effects of marital status on CAD outcomes is limited. This study aimed to evaluate the relationship between marital status and clinical outcomes of patients with CAD stratified according to sex in Korea. Methods A total of 3476 patients with CAD who underwent percutaneous coronary intervention (PCI) were enrolled in this retrospective observational study. Patients were categorized into married and nonmarried groups based on demographic data at the time of admission. The primary endpoint was all-cause mortality. Results Among the study population, 20.7% of women and 11.5% of men who underwent PCI for CAD were nonmarried. For 87.1% of nonmarried women, the cause of being nonmarried was the death of a spouse, whereas for 48.3% of unmarried men, the most common cause was being unmarried. During a median follow-up of 53.3 months, in analysis using the Cox proportional hazard regression model, nonmarried status was associated with higher all-cause [adjusted hazard ratio (HR): 2.24, 95% confidence interval (CI): 1.22–4.09, P = 0.009] and cardiovascular (adjusted HR: 2.63, 95% CI: 19.91–5.80, P = 0.017) deaths in men but not in women. Conclusion Marital status independently predicted the adverse outcomes in men with CAD but not in women, highlighting the importance of sex-specific approaches to the assessment of social determinants in cardiovascular care. Future studies should explore broader social and economic factors to inform targeted interventions.

The efficacy of preoperative transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) remains unclear. This study aimed to investigate the impact of preoperative TACE for resectable solitary HCC. This retrospective study included 4899 patients who underwent hepatectomy from 2008 to 2019. Survival outcomes were compared before and after propensity score matching (PSM) based on tumor size (≤ 3, 3–5, and > 5 cm) between the preoperative TACE (n = 378) and upfront surgery groups (n = 4521). Cox regression analysis was utilized to identify predictors of overall survival (OS) and recurrence-free survival (RFS). For HCC ≤ 3 cm, OS was similar between the groups but RFS significantly improved in the preoperative TACE group both before (OS: p = 0.44; RFS: p < 0.001) and after (OS: p = 0.84; RFS: p < 0.001) PSM. For HCC 3–5 cm, both OS and RFS significantly improved in the preoperative TACE group, both before (OS: p = 0.038; RFS: p < 0.001) and after (OS: p = 0.038; RFS: p < 0.001) PSM. For HCC > 5 cm, OS was not significantly different but RFS improved in the preoperative TACE group both before (OS: p = 0.42; RFS: p = 0.002) and after (OS: p = 0.42; RFS: p = 0.004) PSM. Additionally, complete lipiodol uptake was associated with better OS (p = 0.032) and RFS (p = 0.045) in tumors 3–5 cm compared with incomplete lipiodol uptake. Multivariate analysis identified preoperative TACE and complete lipiodol uptake as significant factors in improving RFS. Preoperative TACE, achieved as complete lipiodol uptake as possible, is recommended to prevent postoperative recurrence of resectable solitary HCC, particularly for tumors measuring 3–5 cm, due to the clear survival benefits in both OS and RFS.

Background Acquired diaphragmatic hernia (DH) is a rare and potentially fatal complication after living donor hepatectomy (LDH). This study aimed to assess the incidence and clinical outcomes of DH after LDH. Methods Four thousand fourteen living donors who underwent LDH at Asan Medical Center, Seoul, between September 2013 and August 2023 were retrospectively reviewed. We analyzed the incidence of DH before and after the introduction of the bipolar irrigated sealer (BIS). Multivariate logistic regression analysis was used to identify the risk factors for DH. Results Postoperative DH occurred in 18 patients (0.40%). Seventeen patients underwent right LDH and developed right-sided DH, whereas 1 patient underwent left LDH and developed left-sided DH. The incidence of DH was 0.22% in the pre-BIS period and >6-fold to 1.36% in the post-BIS period. The median time of postoperative DH occurrence was 11 (range, 3–95) mo. Ten patients underwent elective surgery for DH repair, whereas 8 patients with severe abdominal pain or bowel obstruction underwent emergency surgery, 1 of whom underwent small bowel resection and anastomosis due to severe bowel incarceration. Using BIS was the only significant risk factor for developing DH ( p < 0.001; odd ratio, 6.28; 95% confidence interval, 2.43-16.25). Conclusions Early recognition and surgical repair of DH after LDH should be considered in living donors with unexplained abdominal or thoracic symptoms. Caution is advised when using peridiaphragmatic hemostasis with BIS in liver surgery. We recommend extending the postoperative follow-up of living donors to at least 3 y, including routine imaging screenings for DH.

Background The concept of treatable traits has been proposed for managing chronic cough; however, evidence supporting its clinical utility remains limited. This study investigated the relationship between baseline traits and cough persistence in a prospective registry of patients with chronic cough. Methods We analyzed data from 426 patients with chronic cough enrolled in the Korean Chronic Cough Registry. Eleven potential treatable traits were assessed at baseline. The primary outcome was cough persistence, defined as a cough severity Visual Analog Scale (VAS) score >20 at the last follow-up visit. Results After a median follow-up of 12 months (IQR: 6–24 months), 215 patients (50.5%) had persistent cough (VAS >20). The most prevalent traits were sputum production (60.5%), cough hypersensitivity symptoms (41.8%), and type 2 inflammation (39.1%). Among baseline traits, only cough hypersensitivity symptoms were significantly associated with cough persistence (p=0.024). In multivariate analysis, cough hypersensitivity symptoms (adjusted OR 1.78; 95% CI 1.15–2.78; p=0.010) and older age (≥60 years; adjusted OR 2.07; 95% CI 1.34–3.20; p=0.001) were independently associated with cough persistence. Conclusions These findings suggest that cough hypersensitivity symptoms are associated with long-term outcomes of chronic cough. Further studies are needed to validate the role of treatable traits in chronic cough management and to better understand factors associated with cough persistence.

Fatigue is a state of difficulty maintaining voluntary activity. Cortisol, which is essential for stress regulation, can cause tissue damage when elevated for long periods of time, which is a common problem for office workers in stressful environments. Sleep quality is important for health and cognitive function, while sleep deprivation increases the risk of physical and mental health disorders. Gyrokinesis combines circular, spiral, and wave movements influenced by yoga, tai chi, and ballet to provide a calming effect on the sympathetic nervous system. This study investigated the effects of Gyrokinesis exercise on lower extremity edema, muscle strength, fatigue, and sleep quality in sedentary office workers. Twenty-seven adult women aged 20–40 years were randomly assigned to a Gyrokinesis exercise group (n= 14) or a control group (n= 13). The exercise group participated in 60-min Gyrokinesis sessions twice a week for 8 weeks, while the control group used elastic compression stockings during their working hours. Results showed a significant decrease in fatigue and an improvement in sleep quality in the exercise group. Cortisol and serotonin levels showed a significant between-group interaction effect, with within-group changes observed only in the exercise group. Sleep quality indices improved significantly over time. In conclusion, Gyrokinesis exercise has the potential to improve physical and psychological well-being in sedentary office workers by positively influencing fatigue, sleep quality, and related hormone levels.