Objective: : Chronic subdural hematomas (cSDHs) are generally known to result from traumatic tears of bridging veins. However, the causes of repeat spontaneous cSDHs are still unclear. We investigated the changes in vasculature in the human dura mater and outer membrane (OM) of cSDHs to elucidate the cause of their spontaneous repetition. Methods: : The dura mater was obtained from a normal control participant and a patient with repeat spontaneous cSDHs. The pathological samples from the patient included the dura mater and OM tightly adhered to the inner dura. The samples were analyzed with a particular focus on blood and lymphatic vessels by immunohistochemistry, 3-dimensional imaging using a transparent tissue clearing technique, and electron microscopy. Results: : The dural border cell (DBC) layer of the dura mater and OM were histologically indistinguishable. There were 5.9 times more blood vessels per unit volume of tissue in the DBC layer and OM in the patient than in the normal control. The DBC layer and OM contained pathological sinusoidal capillaries not observed in the normal tissue; these capillaries were connected to the middle meningeal arteries via penetrating arteries. In addition, marked lymphangiogenesis in the periosteal and meningeal layers was observed in the patient with cSDHs. Conclusion : Neovascularization in the OM seemed to originate from the DBC layer; this is a potential cause of repeat spontaneous cSDHs. Embolization of the meningeal arteries to interrupt the blood supply to pathological capillaries via penetrating arteries may be an effective treatment option.

Purpose: To provide a wider choice of treatment opportunities for patients with neuroendocrine tumor (NET) in Korea, we have conducted a phase 1, open-label, single-arm, dose-escalation study of SNU-KB-01, a no-carrier added (NCA) 177Lu-labeled DOTATATE. Materials and Methods: Seven patients with inoperable, progressive, metastatic, or locally advanced, somatostatin receptor-positive NET with Ki67 index ≤ 20% were enrolled according to the rolling six design. The study consisted of two cohorts to receive 4 cycles of SNU-KB-01 every 8 weeks for the first dose of 5.55 GBq (n=3) and 7.40 GBq (n=4). We assessed the incidence of dose-limiting toxicity (DLT) and adverse event, absorbed dose of kidneys and bone marrow, and objective tumor response. Results: Seven patients completed 4 cycles (21.3-30.1 GBq total dose) of SNU-KB-01. The mean absorbed doses to kidneys and bone marrow were 0.500 mGy/MBq and 0.053 mGy/MBq, respectively, and the total body effective dose was 0.115 mSv/MBq. No DLT was observed and the maximum tolerated dose was 7.40 GBq/cycle. Grade 3 thrombocytopenia occurred in one patient, but no other grade 3 or 4 major hematologic or renal toxicity was observed. The best objective response to SNU-KB-01 was partial response. Overall response rate was 42.9% and disease control rate was 85.7%. Conclusion Treatment with 4 cycles of SNU-KB-01 was well tolerated and resulted in control of disease in most of the patients. Our results indicate SNU-KB-01, an NCA 177Lu-labeled DOTATATE, as a potentially safe and efficacious treatment option for NET patients in Korea.

Background: This study aimed to identify the specific T cell co-stimulatory and co-inhibitory factors that play prognostic roles in patients with glioblastoma. Additionally, the unique histone H3 modification enzymes that regulate the expression levels of these specific costimulatory and co-inhibitory factors were investigated. Methods: The medical records of 84 patients newly diagnosed with glioblastoma at our institution from January 2006 to December 2020 were retrospectively reviewed.Immunohistochemical (IHC) staining for T cell co-stimulatory factors (CD27, CD28, CD137, OX40, and ICOS), T cell co-inhibitory factors (CTLA4, PD1, PD-L1, TIM3, and CD200R), and histone H3 lysine modification enzymes (MLL4, RIZ, EZH1, NSD2, KDM5c, JMJD1a, UTX, and JMJD5) was performed on archived paraffin-embedded tissues obtained by biopsy or resection. Quantitative real time-polymerase chain reaction (qRT-PCR) was performed for specific factors, which demonstrated causal relationships, in order to validate the findings of the IHC examinations. Results: The mean follow-up duration was 27.5 months (range, 4.1–43.5 months). During this period, 76 patients (90.5%) died, and the mean OS was 19.4 months (95% confidence interval, 16.3–20.9 months). Linear positive correlations were observed between the expression levels of CD28 and JMJD1a (R2 linear = 0.982) and those of CD137 and UTX (R2 linear = 1.528). Alternatively, significant negative correlations were observed between the expression levels of CTLA4 and RIZ (R2 linear = −1.746) and those of PD-L1 and EZH1 (R2 linear = −2.118); relationships were confirmed by qRT-PCR. In the multivariate analysis, increased expression levels of CD28 (P = 0.042), and CD137 (P = 0.009), and decreased expression levels of CTLA4 (P = 0.003), PD-L1 (P = 0.020), and EZH1 (P = 0.040) were significantly associated with longer survival. Conclusion These findings suggest that the expression of certain T cell co-stimulatory factors, such as CD28 and CD 137, and co-inhibitory factors, such as CTLA4 and PD-L1 are associated with prognosis of glioblastoma patients.

Patients on dialysis have numerous gastrointestinal problems related to uremia, which may represent concealed cholecystitis. We investigated the incidence and risk of acute cholecystitis in dialysis patients and used national health insurance data to identify acute cholecystitis in Korea. Methods: The Korean National Health Insurance Database was used, with excerpted data from the insurance claim of the International Classification of Diseases code of dialysis and acute cholecystitis treated with cholecystectomy. We included all patients who commenced dialysis between 2004 and 2013 and selected the same number of controls via propensity score matching. Results: A total of 59,999 dialysis and control patients were analyzed; of these, 3,940 dialysis patients (6.6%) and 647 controls (1.1%) developed acute cholecystitis. The overall incidence of acute cholecystitis was 8.04-fold higher in dialysis patients than in controls (95% confidence interval, 7.40–8.76). The acute cholecystitis incidence rate (incidence rate ratio, 23.13) was especially high in the oldest group of dialysis patients (aged ≥80 years) compared with that of controls. Dialysis was a significant risk factor for acute cholecystitis (adjusted hazard ratio, 8.94; 95% confidence interval, 8.19–9.76). Acute cholecystitis developed in 3,558 of 54,103 hemodialysis patients (6.6%) and in 382 of 5,896 patients (6.5%) undergoing peritoneal dialysis. Conclusion: Patients undergoing dialysis had a higher incidence and risk of acute cholecystitis than the general population. The possibility of a gallbladder disorder developing in patients with gastrointestinal problems should be considered in the dialysis clinic.

Objective: Suicide is a complex phenomenon; therefore, it should be approached in light of sociocultural perspectives and the general attitude toward suicide. This study aimed to extract factors from the Attitude Toward Suicide Scale (ATTS) and investigate the relationship between attitudes toward suicide and suicidal behavior (i.e., suicidal idea, plan, and attempt) by using a representative sample of Korean adults. Methods: Three thousand Koreans aged 19 to 75 years were surveyed cross-sectionally in 2013 and 2018. The data collected were subjected to exploratory factor analysis. Extracted attitude factors were compared using a suicidal behavior continuum. Univariate and multivariate logistic models were constructed to compare the association between attitude factors and suicidal behaviors. Results: Among the participants, 477 (15.9%) experienced suicidal idea only, 85 (2.8%) had a suicidal plan without attempt, and 58 (1.9%) attempted suicide. Four meaningful factors were extracted from the factor analysis: “permissiveness,” “unjustified behavior,” “preventability/readiness to help,” and “loneliness.” “Permissiveness,” “unjustified behavior,” and “loneliness” factors showed significant trends across the suicidal behavior continuum. Permissive attitude toward suicide increased the odds of suicidal idea, suicidal plan, and suicide attempt (adjusted odds ratio [aOR]=1.49, 95% confidence interval [CI]=1.25–1.79; aOR=2.79, 95% CI=1.84–4.25; aOR=2.67, 95% CI=1.65–4.33), while attitude toward suicide as unjustified behavior decreased the odds of suicidal ideation and attempt (aOR=0.79, 95% CI=0.67–0.94; aOR=0.64, 95% CI=0.42–0.99). Conclusion A significant association was found between attitude toward suicide and suicidal behaviors. Attitude toward suicide is a modifiable factor that can be used to develop prevention policies.

Objective: Elevated levels of cardiac troponin in chronic kidney disease (CKD) patients admitted to the emergency department (ED) is not well understood and is often ignored. This study aimed to investigate the impact of cardiac troponin I (TnI) levels on the clinical outcome of patients visiting the ED with or without CKD. Methods: In this retrospective single-center cohort study, we enrolled patients visiting the ED without a diagnosis of coronary artery disease (CAD). Elevated cardiac TnI was defined as being ≥99th percentile of the normal population (Siemens ADVIA Centaur TnI-Ultra≥0.040 ng/mL). The clinical outcomes of patients with CKD stage≤2 and CKD stage ≥3 were compared. The primary endpoint was the 180-day all-cause death, including cardiovascular and non-cardiovascular deaths. Results: Among a total of 30,472 patients (median age, 61 years; male sex, 54.3%), elevated TnI was found in 4,377 patients (14.4%). There were 3,634 deaths (11.9%) including 584 cardiovascular (1.9%) and 3,050 non-cardiovascular deaths (10.0%). The risk of all-cause death increased in patients with elevated TnI in both CKD stage≤2 (hazard ratio [HR], 2.1; 95% confidence interval [CI], 1.9-2.3) and CKD stage≥3 (HR, 1.5; 95% CI, 1.4-1.7), and so did the risks of cardiovascular and non-cardiovascular death (HR, 1.2-4.7) (P<0.05, all). The association of elevated TnI with death risk was consistent in multivariate analyses and in most clinical subgroup analyses. Conclusion Elevated TnI was associated with higher 180-day mortality irrespective of renal function among patients visiting the ED without documented CAD. CKD patients visiting the ED with elevated TnI may warrant additional evaluation or careful follow-up even without the presence of CAD.

Background/Aims: Several treatment options are currently available for patients with hepatocellular carcinoma (HCC) failing previous sorafenib treatment. We aimed to compare the effectiveness of regorafenib and nivolumab in these patients. Methods: Consecutive HCC patients who received regorafenib or nivolumab after failure of sorafenib treatment were included. Primary endpoint was overall survival (OS) and secondary endpoints were time to progression, tumor response rate, and adverse events. Inverse probability of treatment weighting (IPTW) using the propensity score was conducted to reduce treatment selection bias. Results: Among 150 study patients, 102 patients received regorafenib and 48 patients received nivolumab. Median OS was 6.9 (95% confidence interval [CI], 3.0–10.8) months for regorafenib and 5.9 (95% CI, 3.7–8.1) months for nivolumab (P=0.77 by log-rank test). In multivariable analysis, nivolumab was associated with prolonged OS (vs. regorafenib: adjusted hazard ratio [aHR], 0.54; 95% CI, 0.30–0.96; P=0.04). Time to progression was not significantly different between groups (nivolumab vs. regorafenib: aHR, 0.82; 95% CI, 0.51–1.30; P=0.48). HRs were maintained after IPTW. Objective response rates were 5.9% and 16.7% in patients treated with regorafenib and nivolumab, respectively (P=0.04). Conclusions After sorafenib failure, the use of nivolumab may be associated with improved OS and better objective response rate as compared to using regorafenib.

Background and Objectives: Outbred mice are widely used in toxicology, pharmacology, and fundamental biomedical research. However, there have been no reports of in vitro culture systems for spermatogonial stem cells (SSCs) derived from these mice. Methods: As a step towards constructing a non-cellular niche supporting the in vitro maintenance of outbred mouse SSC self-renewal, we systematically investigated the types of integrin heterodimers that are expressed transcriptionally, translationally, and functionally in SSCs derived from Imprinting Control Region (ICR) mice. Results: Among the genes encoding 25 integrin subunits, integrin α1, α5, α6, α9, αV, and αE, and integrin β1 and β5 had significantly higher transcriptional levels than the other subunits. Furthermore, at the translational level, integrin α5, α6, α9, αV, and αE, and β1 were localized on the surface of SSCs, but integrin α1 and β5 not. Moreover, significantly stronger translational expression than integrin α9 and αE was observed in integrin α5, α6, αV, and β1. SSCs showed significantly increased adhesion to fibronectin, laminin, tenascin C and vitronectin, and functional blocking of integrin α5β1, α6β1, α9β1 or αVβ1 significantly inhibited adhesion to these molecules. Conclusions We confirmed that integrin α5β1, α6β1, α9β1 and αVβ1 actively function on the surface of undifferentiated SSCs derived from outbred ICR mice.

Background/Aims: Although the diarrheal disease caused by Campylobacter bacteria has been continuously increasing in Korea, there has been limited study on the clinical aspects of Campylobacter enteritis in adults in Korea. The purpose of this study was to analyze the clinical features and characteristics of adult patients with Campylobacter enteritis. Methods: This retrospective study included patients diagnosed with Campylobacter enterocolitis at Nowon Eulji University Hopsital between January 2016 and December 2017. Campylobacter enterocolitis was diagnosed through polymerase chain reaction of stools from patients with acute diarrhea. Results: Among 630 hospitalized patients with acute diarrhea, Campylobacter enterocolitis was diagnosed in 88 patients (14.0%). The mean age was 37.9±19.1 years. Campylobacter enterocolitis was most prevalent in the summer (52 patients, 59.1%). Patients exhibited more than 10 times of diarrhea in 36 (40.9%), high fever above 39℃ in 19 (21.59%), and abdominal pain above 5 points on the numeric rating scale in 23 (26.14%) cases. In abdominal CT scan, pancolitis was found in 58 patients (65.9%). Small intestine was involved in 37 patients (42.4%). Mean CRP was 10.14 mg/dL (range 0.72-32.27 mg/dL). The duration of diarrhea after antibiotics treatment was 2.34±1.51 days in the ciprofloxacin treatment group and 2.26±1.71 days in the 3rd cephalosporin treatment group. Conclusions Campylobacter enterocolitis was common during summer. Commonly healthy young adults were hospitalized due to severe symptoms of Campylobacter enterocolitis. Whole colon and small bowel were frequently involved. Most patients were treated with antibiotics, and the efficacy of 3rd cephalosporin treatment was not inferior to that of ciprofloxacin treatment.