Purpose: We identified the risk factors for remnant gastric cancer (RGC) based on remnant gastric mucosal characteristics and gastritis morphology in patients undergoing distal gastrectomy. Materials and Methods: This multicenter retrospective study included 100 patients with RGC after distal gastrectomy and 550 patients without RGC treated between 2013 and 2020.Endoscopic findings, including anastomotic redness, red streaks, enlarged folds, bile reflux as anastomotic findings, as well as disappearance of the regular arrangement of collecting venules (RAC), atrophic gastritis, and intestinal metaplasia as background gastric mucosal findings, were evaluated. Disease risk score matching (1:1) was adjusted for baseline characteristics. Logistic regression analysis was used to develop a risk score model to stratify RGC risk into low, moderate, and high categories. Results: After matching, 96 patients with RGC and 96 controls were analyzed. Anastomotic redness and red streaks, as well as the disappearance of RAC and atrophic gastritis, were significantly more frequent in the RGC group than in the control group, whereas enlarged folds and bile reflux showed no significant differences. Risk scores were assigned as follows:anastomotic redness, 2; red streaks, 3; disappearance of RAC, 7; and atrophic gastritis, 3. The total score stratified patients into high (≥15), moderate (7–14), and low risk (≤6). The positive and negative predictive values were 67.7% and 83.3%, respectively. Conclusions The endoscopic findings of anastomotic redness, red streaks, RAC disappearance, and atrophic gastritis were significantly associated with RGC development.The proposed risk-scoring model could serve as a stratification tool for RGC surveillance.

Background: The potassium voltage-gated channel subfamily Q member 1 (KCNQ1) gene has recently received much attention as a candidate susceptibility gene for type 2 diabetes mellitus, especially in Asian populations. We previously reported that Kcnq1 mutant mice exhibit reduced insulin secretion and hyperglycemia due to a decrease in pancreatic β-cell mass. Through in vivo and in vitro analyses, we ascertained that this mechanism is the result of the downregulation of the non-coding RNA ‘Kcnq1ot1,’ which is expressed in the paternal allele of the Kcnq1 gene region, causing an increase in the expression of the cell cycle inhibitor cyclin dependent kinase inhibitor 1C (Cdkn1c). It was found that decreased Kcnq1ot1 expression resulted in pancreatic β-cell failure; however, the degree of pancreatic β-cell volume reduction was not severe. Methods: We induced obesity in Kcnq1ot1 truncation mice by feeding them a high-fat diet and evaluated pancreatic β-cell mass. Results: In the present study, we reveal that CCAAT/enhancer binding protein beta (C/EBPβ), which is expressed at higher levels in pancreatic β-cells in obese individuals, further increases the expression of Cdkn1c, which is upregulated by the Kcnq1 gene mutation. We found that simultaneous Cdkn1c hypomethylation and C/EBPβ overexpression in pancreatic β-cells causes a synergistic decrease in pancreatic β-cell mass. Conclusion This finding suggests that the synergistic effect of genetic factors such as Kcnq1 gene mutations and environmental factors such as obesity and overeating, which lead to increased expression of C/EBPβ, contribute to the regulation of pancreatic β-cell mass. This study is the first to show that the Kcnq1 gene is related to pancreatic β-cell mass through genetic-environment interactions.

Background/Aims: Mechanical properties (MPs) and axial and radial force (AF and RF) may influence the efficacy and complications of self-expandable metallic stent (SEMS) placement. We measured the MPs of various SEMSs and examined their influence on the SEMS clinical ability. Methods: We evaluated the MPs of 29 types of 10-mm SEMSs. RF was measured using a conventional measurement device. AF was measured using the conventional and new methods, and the correlation between the methods was evaluated. Results: A high correlation in AFs was observed, as measured by the new and conventional manual methods. AF and RF scatterplots divided the SEMSs into three subgroups according to structure: hook-and-cross-type (low AF and RF), cross-type (high AF and low RF), and laser-cut-type (intermediate AF and high RF). The hook-and-cross-type had the largest axial force zero border (>20°), followed by the laser-cut and cross types. Conclusions MPs were related to stent structure. Hook-and-cross-type SEMSs had a low AF and high axial force zero border and were considered safest because they caused minimal stress on the biliary wall. However, the increase in RF must be overcome.

Background/Aims: Patients with achalasia-related esophageal motility disorders (AEMDs) frequently present with dilated and sigmoid esophagus, anddevelop esophageal diverticulum (ED), although the prevalence and patients characteristics require further elucidation. Methods: We conducted a multicenter cohort study of 3707 patients with AEMDs from 14 facilities in Japan. Esophagography on 3682 patients were analyzed. Results: Straight (n = 2798), sigmoid (n = 684), and advanced sigmoid esophagus (n = 200) were diagnosed. Multivariate analysis revealed that long disease duration, advanced age, obesity, and type I achalasia correlate positively, whereas severe symptoms and integrated relaxation pressure correlate negatively with development of sigmoid esophagus. In contrast, Grade II dilation (3.5-6.0 cm) was the most common (52.9%), while grade III dilation (≥ 6 cm) was rare (5.0%). We found early onset, male, obesity, and type I achalasia correlated positively, while advanced age correlated negatively with esophageal dilation. Dilated and sigmoid esophagus were found mostly in types I and II achalasia, but typically not found in spastic disorders. The prevalence of ED was low (n = 63, 1.7%), and non-dilated esophagus and advanced age correlated with ED development. Patients with right-sided ED (n = 35) had a long disease duration (P = 0.005) with low integrated relaxation pressure values (P = 0.008) compared with patients with left-sided ED (n = 22). Patients with multiple EDs (n = 6) had lower symptom severity than patients with a single ED (P = 0.022). Conclusions The etiologies of dilated esophagus, sigmoid esophagus, and ED are considered multifactorial and different. Early diagnosis and optimal treatment of AEMDs are necessary to prevent these conditions.

The main pathogenic mechanism of diabetes consists of an increase in insulin resistance and a decrease in insulin secretion from pancreatic β-cells. The number of diabetic patients has been increasing dramatically worldwide, especially in Asian people whose capacity for insulin secretion is inherently lower than that of other ethnic populations. Causally, changes of environmental factors in addition to intrinsic genetic factors have been considered to have an influence on the increased prevalence of diabetes. Particular focus has been placed on “gene-environment interactions” in the development of a reduced pancreatic β-cell mass, as well as type 1 and type 2 diabetes mellitus. Changes in the intrauterine environment, such as intrauterine growth restriction, contribute to alterations of gene expression in pancreatic β-cells, ultimately resulting in the development of pancreatic β-cell failure and diabetes. As a molecular mechanism underlying the effect of the intrauterine environment, epigenetic modifications have been widely investigated. The association of diabetes susceptibility genes or dietary habits with gene-environment interactions has been reported. In this review, we provide an overview of the role of gene-environment interactions in pancreatic β-cell failure as revealed by previous reports and data from experiments.

Objective：To assess the risk for hyperkalemia caused by treatment with angiotensin Ⅱ Type 1 receptor blockers （ARB） in clinical practice with Japanese medical database.Design：A cohort study in patients treated with ARB alone and those treated with calcium channel blockers （CCB） alone as control.Methods：The Diagnosis Procedure Combination （DPC） database provided by Medical Data Vision Co., Ltd. was used to identify patients who received a diagnosis of hypertension (ICD-10 codes, I10 to I15) and were treated with ARB or CCB from April 2008 to June 2017. A logistic regression model was applied to estimate adjusted odds ratios （OR） and their 95％ confidence intervals （CI） in these patients. The outcome in the logistic model was hyperkalemia （serum potassium≧5.5 mEq/L） and the covariates were sex, age, renal insufficiency, hepatic insufficiency, and baseline serum potassium levels. And, subgroup analysis was also performed in patients with and without renal insufficiency.Results：The incidence of hyperkalemia （per 1000 person-years） with ARB was 39.4 and that with CCB was 32.6. And, median periods from the index date to the date of occurrence of hyperkalemia for both exposure and control groups were 36 days （Min-Max：12-85） and 51.5 days（Min-Max：8-88）respectively. However, treatment with ARB was not associated with occurrence of hyperkalemia （OR 1.26, 95％CI： 0.58-2.75). The risk for hyperkalemia among those with renal insufficiency was higher （OR 3.31, 95％CI： 1.39-7.88）and as baseline serum potassium increased, the risk increased as well （OR 9.20, 95％CI： 3.52-24.10). And, the subgroup analysis also showed that rare occurrence of hyperkalemia by ARB and elevation risk for hyperkalemia by baseline serum potassium.Conclusion：The clinical data showed rare occurrence of hyperkalemia caused by ARB, indicating that renal insufficiency and baseline serum potassium levels affected the onset of the disease in clinical practice. Previous studies also reported the effects of renal insufficiency and other factors on the onset of hyperkalemia. ARB should be prescribed carefully in patients with these factors, as is conventionally done.

The Trail Making Test (TMT) is a widely used measure of attention impairment. The time needed to complete the TMT (TMT score) is longer with greater impairment of attention in patients with brain diseases. TMT score becomes large in a proportion of patients with minor ischemic stroke. The Japanese version of the TMT- (TMT-J) was published in 2019. The purpose of this study was to clarify serial changes in TMT-J scores in patients with minor ischemic stroke. We retrospectively reviewed the TMT-J scores in those patients who completed the test both 8-14 days and 29-35 days after stroke onset. On initial evaluation, 1 of 21 patients could not complete TMT-J Part A. TMT-J Part A scores had a mean of 67 s and were abnormally large in 45% of the 20 patients who completed this part. Two of these 20 patients could not complete TMT-J Part B. TMT-J Part B scores had a mean of 135 s and were abnormally large in 61% of the 18 patients who completed this part. On second evaluation, scores on Part A and Part B improved in 76% and 73% of patients, respectively. This study demonstrated that abnormal TMT-J scores 8-14 days after onset of minor ischemic stroke improved over time in most patients.

Evidence is growing on adverse health outcomes associated with less physical activity (PA) and more sedentary behavior (SB). As most workers generally spend approximately one-third of the day at work, measuring the amount of occupational PA/SB time would contribute to understanding the health risks of physical inactivity and SB among workers. In this review article, we describe the amount of time spent in different intensities of activity (moderate-to-vigorous PA [MVPA]; light PA [LPA]; and SB), on work and non-work days, while at work and outside working hours among workers. The review used objective measurements made by an accelerometer and showed the proportion of MVPA that office workers engaged in on work and non-work days accounted for 3-5% and 2-4% of accelerometer wear time, respectively. Moreover, office workers spent more time in SB and less time in LPA on work days than non-work days (SB, 66-76% vs. 60-69%; LPA, 20-28% vs. 23-36%). Especially on work days, office workers spent the greatest proportion of the day in SB during working hours (71-82%), compared with that outside working hours (63-67%). The proportion of MVPA accounted for 2-5% during working hours and 3-7% outside working hours. In addition, there were considerable differences in the proportions of LPA and SB between white-collar and blue-collar workers during working hours (SB, 73 vs. 55%; LPA; 22 vs. 40%), whereas the MVPA time was similar (5 vs. 5%). Some occupational exposure to unfavorable PA/SB at work might be unavoidable; however, inadequate PA/SB during working hours should be corrected.

Calcified amorphous tumor (CAT) is a non-neoplastic mass characterized by calcified nodules that was first reported in 1997. It is often associated with dialysis or mitral annular calcification (MAC). CAT is considered a risk factor for systemic embolism, but there has been no report of CAT damaging the native valve tissue and leading to valvular disease. An 81-year-old woman had shortness of breath on exertion starting 1 year previously, and was referred to our hospital with cardiac murmur detected on physical examination. Echocardiography showed evidence of severe mitral valve regurgitation with ruptured chordae tendineae of the posterior leaflet and a poorly mobile club-shaped structure protruding into the left ventricle and appearing to be continuous with MAC. She underwent elective mitral valve repair. A club-shaped calcification originating from MAC was found under the P2 segment, with ruptured P2 chordae tendineae immediately above it and mitral perforation in the contralateral A2 segment, which were likely to have resulted from direct damage by the hard structure. Mitral valve repair was successful with mass resection, triangular resection of the posterior leaflet P2 segment, and closure of the perforation. Histopathological findings of the mass were consistent with CAT, with no evidence of infection or malignancy. CAT may not only cause embolism but also grow while damaging the native valve tissue. It is important to closely follow-up and perform surgery in proper timing.