Involvement of Ca2+ in Signaling Mechanisms Mediating Muscarinic Inhibition of M Currents in Sympathetic Neurons.

Acetylcholine can excite neurons by suppressing M-type (KCNQ) potassium channels. This effect is mediated by M1 muscarinic receptors coupled to the Gq protein. Although PIP2 depletion and PKC activation have been strongly suggested to contribute to muscarinic inhibition of M currents (IM), direct evidence is lacking. We investigated the mechanism involved in muscarinic inhibition of IM with Ca2+ measurement and electrophysiological studies in both neuronal (rat sympathetic neurons) and heterologous (HEK cells expressing KCNQ2/KCNQ3) preparations. We found that muscarinic inhibition of IM was not blocked either by PIP2 or by calphostin C, a PKC inhibitor. We then examined whether muscarinic inhibition of IM uses multiple signaling pathways by blocking both PIP2 depletion and PKC activation. This maneuver, however, did not block muscarinic inhibition of IM. Additionally, muscarinic inhibition of IM was not prevented either by sequestering of G-protein ßγ subunits from Gα-transducin or anti-Gßγ antibody or by preventing intracellular trafficking of channel proteins with blebbistatin, a class-II myosin inhibitor. Finally, we re-examined the role of Ca2+ signals in muscarinic inhibition of IM. Ca2+ measurements showed that muscarinic stimulation increased intracellular Ca2+ and was comparable to the Ca2+ mobilizing effect of bradykinin. Accordingly, 20-mM of BAPTA significantly suppressed muscarinic inhibition of IM. In contrast, muscarinic inhibition of IM was completely insensitive to 20-mM EGTA. Taken together, these data suggest a role of Ca2+ signaling in muscarinic modulation of IM. The differential effects of EGTA and BAPTA imply that Ca2+ microdomains or spatially local Ca2+ signals contribute to inhibition of IM.

Single-Cell Network-Based Drug Repositioning for Discovery of Therapies against Anti-Tumour Necrosis Factor-Resistant Crohn's Disease.

Primary and secondary non-response affects approximately 50% of patients with Crohn's disease treated with anti-tumour necrosis factor (TNF) monoclonal antibodies. To date, very little single cell research exists regarding drug repurposing in Crohn's disease. We aimed to elucidate the cellular phenomena underlying resistance to anti-TNF therapy in patients with Crohn's disease and to identify potential drug candidates for these patients. Single-cell transcriptome analyses were performed using data (GSE134809) from the Gene Expression Omnibus and Library of Integrated Network-Based Cellular Signatures L1000 Project. Data aligned to the Genome Reference Consortium Human Build 38 reference genome using the Cell Ranger software were processed using the Seurat package. To capture significant functional terms, gene ontology functional enrichment analysis was performed on the marker genes. For biological analysis, 93,893 cells were retained (median 20,163 genes). Through marker genes, seven major cell lineages were identified: B-cells, T-cells, natural killer cells, monocytes, endothelial cells, epithelial cells, and tissue stem cells. In the anti-TNF-resistant samples, the top 10 differentially expressed genes were HLA-DQB-1, IGHG1, RPS23, RPL7A, ARID5B, LTB, STAT1, NAMPT, COTL1, ISG20, IGHA1, IGKC, and JCHAIN, which were robustly distributed in all cell lineages, mainly in B-cells. Through molecular function analyses, we found that the biological functions of both monocyte and T-cell groups mainly involved immune-mediated functions. According to multi-cluster drug repurposing prediction, vorinostat is the top drug candidate for patients with anti-TNF-refractory Crohn's disease. Differences in cell populations and immune-related activity within tissues may influence the responsiveness of Crohn's disease to anti-TNF agents. Vorinostat may serve as a promising novel therapy for anti-TNF-resistant Crohn's disease.

1 L- versus 2 L-polyethylene glycol with ascorbic acid for bowel preparation in elderly patients: a randomized multicenter study.

BACKGROUND: 1 L-polyethylene glycol (PEG)/ascorbic acid (Asc) was developed to reduce the required oral preparation volume through increasing osmotic load through containing a greater quantity of ascorbate components. We aimed to compare the efficacy, tolerability, and safety of a split-dosing regimen of 1 L-PEG/Asc versus 2 L-PEG/Asc in elderly patients undergoing scheduled colonoscopy. METHODS: This was a prospective, non-inferiority, randomized, investigator-blinded multicenter study conducted in Korea between July 2019 and December 2020. Patients aged between 65 and 85 years were randomized at a ratio of 1:1 to either the 1 L-PEG/Asc or 2 L-PEG/Asc group. The efficacy of the bowel preparation was evaluated using the Harefield Cleansing Scale (HCS) and the Boston Bowel Preparation Scale (BBPS). RESULTS: A total of 202 patients were analyzed. Successful overall bowel preparation was similar between the 1 L-PEG/Asc and 2 L-PEG/Asc groups based on HCS (95.1% vs. 93.1%, P = 0.528) and BBPS (93.1% vs. 90.0%, P = 0.422). The perfect overall bowel preparation rate in the 1 L-PEG/Asc group was higher than that in the 2 L-PEG/Asc group (HCS, 40.2% vs. 25.0%, P = 0.021; BBPS, 80.4% vs. 68.0%, P = 0.044). There were more high-quality bowel preparations for the right colon in the 1 L-PEG/Asc group (HCS, 46.1% vs. 30.0%, P = 0.019; BBPS, 83.3% vs. 70.0%, P = 0.025). The adenoma detection rate (47.1% vs. 49.0%, P = 0.782), rate of adverse events (25.5% vs. 23.0%, P = 0.680), shifts in laboratory results, and tolerability were comparable between the groups. CONCLUSION: 1 L-PEG/Asc was as effective, safe, and tolerable as 2 L-PEG/Asc in elderly patients with comorbidities.

Artificial intelligence-based measurement outperforms current methods for colorectal polyp size measurement.

OBJECTIVES: An accurate polyp size estimation during colonoscopy is crucial to determine the surveillance interval and predict the risk of malignant progression. However, there is a high degree of subjectivity in estimating polyp size among endoscopists in clinical practice. We aimed to assess the efficacy of a novel method that uses artificial intelligence (AI) to measure the size of colon polyps and compare it with current approaches. METHODS: Using the W-Net model for vessel segmentation and based on retinal image datasets (DRIVE, STARE, CHASE-DB, and HRF) and colonoscopy images, we developed the bifurcation-to-bifurcation (BtoB) distance measuring method and applied it to endoscopic images. Measurements were compared with those obtained by eight endoscopists (four expert and four trainees). Diagnostic ability and reliability were evaluated using Lin's concordance correlation coefficients (CCCs) and Bland-Altman analyses. RESULTS: For both experts and trainees, visually estimated sizes of the same polyp were significantly inconsistent depending on the camera view used (P < 0.001). Bland-Altman analyses showed that there was a trend toward underestimation of the sizes of the polyps in both groups, especially for polyps larger than 10 mm. The new technique was highly accurate and reliable in measuring the size of colon polyp (CCC, 0.961; confidence interval 0.926-0.979), clearly outperforming the visual estimation and open biopsy forceps methods. CONCLUSION: The new AI measurement method improved the accuracy and reliability of polyp size measurements in colonoscopy images. Incorporating AI might be particularly important to improve the efficiency of trainees at estimating polyp size during colonoscopy.

Seasonal variations in the diagnosis of the top 10 cancers in Korea: A nationwide population-based study using a common data model.

BACKGROUND AND AIM: A better understanding of seasonal variations in cancer diagnosis may be the first step toward optimal resource distribution in the National Cancer Screening Program (NCSP). This study aimed to identify seasonal variations in the diagnosis of the top 10 major cancers in Korea. METHODS: We conducted a retrospective, observational cohort study in participants aged ≥ 20 years between 2012 and 2016 from the Health Insurance Review and Assessment-National Patient Sample database, previously converted to a common data model. We assessed the overall seasonal variations in the 10 major cancers. RESULTS: We analyzed the following top 10 cancers: stomach (n = 3435), colorectal (n = 5368), liver (n = 7605), pancreatic (n = 2946), gallbladder (n = 899), lung (n = 1598), prostate (n = 2897), thyroid (n = 1966), breast (n = 1313), and kidney (n = 668) cancers. All cancers showed similar seasonal variations in diagnosis, with a significant winter peak. A winter peak in diagnosis was observed for NCSP-covered cancers, such as stomach, colon, liver, and breast cancers, as well as other cancers not covered by the NCSP. The winter peak for cancer diagnosis was the highest for breast cancer (74.4%) followed by thyroid (51.0%) and stomach cancers, whereas it was the lowest for pancreatic cancer followed by prostate and colorectal cancers. CONCLUSIONS: Significant seasonal variations were found in the diagnosis of the top 10 major cancers, with a winter peak, which may be explained by the participants' behavior pattern with respect to the NCSP. Our findings suggest that trading off of NCSP healthcare resources between winter and other seasons may be beneficial.

Early course of newly diagnosed moderate-to-severe ulcerative colitis in Korea: Results from a hospital-based inception cohort study (MOSAIK).

BACKGROUND AND AIM: No inception cohort study has ever evaluated the early course of moderate-to-severe ulcerative colitis (UC) within 1 year of diagnosis in the non-Caucasian population. We aimed to investigate the early clinical course of moderate-to-severe UC patients in terms of remission, relapse, UC-related hospitalizations, colectomy, mortality, and overall use of medications. METHODS: In the MOSAIK inception cohort, which is an ongoing multicenter, prospective, hospital-based, observational cohort, 354 patients with moderate-to-severe UC were followed up for 1 year. Main outcomes of UC and predictive factors for medication use over the course of 1 year were evaluated. RESULT: Among 354 patients, 276 (78.0%) patients were followed up for 1 year. The rates of remission, relapse, UC-related hospitalizations, and proximal disease extension were 95.3%, 39.6%, 15.2%, and 12.3%, respectively. Systemic corticosteroids, thiopurines, and biologics were administered to 61.2%, 30.4%, and 10.5% of patients, respectively, throughout 1 year. One year after, 58.2% patients experienced remission or mild endoscopic activity. Overall disease courses did not show much difference according to moderate or severe disease activity at baseline. In addition, no colectomy and mortality were observed for 1 year. Predictive factors for medication use included disease severity, disease extent, endoscopic severity, and presence of periappendiceal inflammation at baseline for corticosteroid, disease extent and initial corticosteroid use for thiopurine, and only initial corticosteroid use for biologics. CONCLUSION: Korean patients with moderate-to-severe UC may have more favorable early outcomes than Western patients. However, outcomes of them need to be further looked into for a longer time.

Real-World Use of Colonoscopy in an Older Population: A Nationwide Standard Cohort Study Using a Common Data Model.

BACKGROUNDS AND AIMS: Rapid population aging is considered to be a major factor in increased colonoscopy use in Korea. However, real-world use of colonoscopy in older populations is rarely evaluated using Korean databases. METHODS: We conducted a retrospective, observational cohort study of individuals aged over 20 years between 2012 and 2017. We used the Health Insurance Review and Assessment-National Patient Samples database, previously converted to the standardized Observational Medical Outcomes Partnership-Common Data Model. The use of diagnostic colonoscopy and colonoscopic polypectomy was evaluated, stratified by age group and sex. RESULTS: During the study period, we captured data from the database on 240,406 patients who underwent diagnostic colonoscopy and 88,984 who underwent colonoscopic polypectomy. During the study period, use of diagnostic colonoscopy and colonoscopic polypectomy steadily increased, but both procedures were most significantly increased in the 65- to 85-year group compared to other age groups (p < 0.05). Average ages for both procedures significantly increased in the most recent 3 years (p < 0.05). Polypectomy rates for men plateaued in the 50- to 64-year age group, but rates for women steadily increased up to the 65- to 85-year group. Polypectomy rates were higher for men than for women in all index years. CONCLUSIONS: The use of diagnostic colonoscopy and colonoscopic polypectomy significantly increased in the 65- to 85-year age group. Our findings suggest that more available colonoscopy resources should be allocated to older populations, considering the aging society in Asian countries.

Pretreatment with Ranitidine Bismuth Citrate May Improve Success Rates of Helicobacter pylori Eradication: A Prospective, Randomized, Controlled and Open-Label Study.

Effective Helicobacter pylori (H. pylori) eradication is a major public health concern; however, eradication failure rates with the standard triple therapy remain high. We aimed to investigate the effectiveness and tolerability of ranitidine bismuth citrate (RBC) pretreatment before standard triple therapy for H. pylori eradication. A prospective, randomized, controlled, and open-label clinical trial was conducted from June to December 2019. H. pylori eradication rate, safety, and tolerability were compared between the standard treatment group (esomeprazole, amoxicillin, and clarithromycin for 7 days) and RBC pretreatment group (RBC for 2 weeks before standard triple therapy). This trial ended earlier than estimated owing to the N-nitrosodimethylamine concerns with ranitidine. Success rates of H. pylori eradication were 80.9% and 67.3% in the RBC pretreatment (n = 47) and standard treatment (n = 52) (p = 0.126) groups, respectively. Our trial was discontinued earlier than planned; however, a statistical significance would be achieved by expansion of our data (p = 0.031) if patient enrollment numbers reached those initially planned. Adverse event rates were comparable between groups (25.5% in the pretreatment group vs. 28.8% in the standard treatment group), without serious event. Tolerability was excellent in both groups, recorded as 97.9% and 100% in the pretreatment and standard treatment groups, respectively. Compared with the standard triple regimen, RBC pretreatment for 2 weeks may achieve higher H. pylori eradication rates, with excellent safety and tolerability. However, this study necessitates further validation as it was discontinued early owing to the N-nitrosodimethylamine issues of ranitidine.

Modulation of the cardiac sodium channel NaV1.5 peak and late currents by NAD+ precursors.

RATIONALE: The cardiac sodium channel NaV1.5, encoded by SCN5A, produces the rapidly inactivating depolarizing current INa that is responsible for the initiation and propagation of the cardiac action potential. Acquired and inherited dysfunction of NaV1.5 results in either decreased peak INa or increased residual late INa (INa,L), leading to tachy/bradyarrhythmias and sudden cardiac death. Previous studies have shown that increased cellular NAD+ and NAD+/NADH ratio increase INa through suppression of mitochondrial reactive oxygen species and PKC-mediated NaV1.5 phosphorylation. In addition, NAD+-dependent deacetylation of NaV1.5 at K1479 by Sirtuin 1 increases NaV1.5 membrane trafficking and INa. The role of NAD+ precursors in modulating INa remains unknown. OBJECTIVE: To determine whether and by which mechanisms the NAD+ precursors nicotinamide riboside (NR) and nicotinamide (NAM) affect peak INa and INa,Lin vitro and cardiac electrophysiology in vivo. METHODS AND RESULTS: The effects of NAD+ precursors on the NAD+ metabolome and electrophysiology were studied using HEK293 cells expressing wild-type and mutant NaV1.5, rat neonatal cardiomyocytes (RNCMs), and mice. NR increased INa in HEK293 cells expressing NaV1.5 (500 µM: 51 ± 18%, p = .02, 5 mM: 59 ± 22%, p = .03) and RNCMs (500 µM: 60 ± 26%, p = .02, 5 mM: 74 ± 39%, p = .03) while reducing INa,L at the higher concentration (RNCMs, 5 mM: -45 ± 11%, p = .04). NR (5 mM) decreased NaV1.5 K1479 acetylation but increased INa in HEK293 cells expressing a mutant form of NaV1.5 with disruption of the acetylation site (NaV1.5-K1479A). Disruption of the PKC phosphorylation site abolished the effect of NR on INa. Furthermore, NAM (5 mM) had no effect on INa in RNCMs or in HEK293 cells expressing wild-type NaV1.5, but increased INa in HEK293 cells expressing NaV1.5-K1479A. Dietary supplementation with NR for 10-12 weeks decreased QTc in C57BL/6 J mice (0.35% NR: -4.9 ± 2.0%, p = .14; 1.0% NR: -9.5 ± 2.8%, p = .01). CONCLUSIONS: NAD+ precursors differentially regulate NaV1.5 via multiple mechanisms. NR increases INa, decreases INa,L, and warrants further investigation as a potential therapy for arrhythmic disorders caused by NaV1.5 deficiency and/or dysfunction.

Clinical outcomes and factors related to colonic perforations in patients receiving self-expandable metal stent insertion for malignant colorectal obstruction.

BACKGROUND AND AIMS: Although colonic perforation is a dreadful adverse event associated with stent placement, data on this topic are sparse. We aimed to investigate the clinical outcomes of colonic perforation and factors related to its occurrence in patients who received self-expandable metal stents (SEMSs) for malignant colorectal obstruction. METHODS: We retrospectively reviewed the data of 474 patients with malignant colorectal obstruction who received endoscopic SEMS insertion from April 2004 to May 2011 in Severance Hospital and Gangnam Severance Hospital. Early perforation, defined as perforation occurring within 2 weeks, was assessed in bridge-to-surgery (n = 164) and palliative stent placement patient groups (n = 310). Delayed perforation was analyzed using data from the palliative stent placement group alone. RESULTS: The technical and clinical success rates were 90.5% and 81.0%, respectively. Early and delayed perforations occurred in 2.7% (13/474) and 2.7% (8/301) of patients, respectively. Among 21 patients with perforation, 14 (66.7%) received emergency surgery and 5 (23.8%) died within 30 days after perforation. Regarding the perforation-related factors, age ≥70 years (odds ratio, 3.276; 95% confidence interval [CI], 1.041-10.309) and sigmoid colonic location (odds ratio, 7.706; 95% CI, 1.681-35.317) were independently associated with occurrence of early perforation. Stent location in the flexure (hazard ratio, 17.573; 95% CI, 2.004-154.093) and absence of peritoneal carcinomatosis (hazard ratio, 6.139; 95% CI, 1.150-32.776) were significantly associated with delayed perforation. CONCLUSIONS: The perforation-related 30-day mortality rate was 23.8%. Older age and sigmoid colonic location were significantly associated with occurrence of early perforation, whereas flexure location and absence of peritoneal carcinomatosis were related to delayed perforation.

Impact of peritoneal carcinomatosis on clinical outcomes of patients receiving self-expandable metal stents for malignant colorectal obstruction.

BACKGROUND: Peritoneal carcinomatosis can influence clinical outcomes of patients receiving self-expandable metal stents (SEMS) for malignant colorectal obstruction, but data regarding this issue are sparse. We analyzed the clinical outcomes of post-SEMS insertion for malignant colorectal obstruction based on carcinomatosis status. METHODS: Stent- and patient-related clinical outcomes were compared for carcinomatosis status in a retrospective review involving 323 consecutive patients (colorectal cancer 198 patients; extracolonic malignancy 125 patients) who underwent palliative SEMS placement for malignant colorectal obstruction from January 2005 to March 2012. Severity of carcinomatosis was classified as mild, moderate, or severe. RESULTS: Carcinomatosis was observed in 190 patients (58.8 %). The rates of technical (84.7 vs. 94.7 %; P = 0.005) and clinical (73.2 vs. 83.5 %; P = 0.03) success were lower in patients with vs. without carcinomatosis. Rates of early (2.1 % vs. 3.0 %; P = 0.72) and delayed (1.6 % vs. 6.0 %; P = 0.08) perforation and stent failure (27.9 % vs. 26.3 %; P = 0.75) showed no difference. Technical and clinical success rates were significantly different based on the severity of carcinomatosis (technical success rate: mild 90.7 %, moderate 97.4 %, severe 76.3 %, P = 0.003; clinical success rate: mild 83.3 %, moderate 82.1 %, severe 63.9 %, P = 0.01). In multivariate analysis, severe carcinomatosis was identified as an independent factor related to technical (odds ratio [OR] 0.18, 95 % confidence interval [CI] 0.06 - 0.56) and clinical (OR 0.33, 95 %CI 0.15 - 0.74) success. CONCLUSIONS: Peritoneal carcinomatosis was associated with decreased technical and clinical success rates in patients receiving SEMS for malignant colorectal obstruction. Moreover, the presence of severe carcinomatosis was an independent factor determining these clinical outcomes.

An Adjusted Level of Adenoma Detection Rate is Necessary for Adults Below 50 Years Old.

BACKGROUND: Although adenoma prevalence is lower in younger people compared with screening-aged adults 50 years old and above, there is no adjustment recommendation for the target adenoma detection rate (ADR) in young people. Herein, we estimated a different target ADR for adults below 50 years old based on screening colonoscopy findings. MATERIALS AND METHODS: Asymptomatic, average-risk adults below 50 years old who underwent screening colonoscopy were enrolled at 12 endoscopy centers in Korea between February 2006 and March 2012. Screening colonoscopies were stratified into low or high ADR groups with ADR levels of 20% and 25%, respectively. RESULTS: The ADRs from 12 endoscopy centers ranged from 12.1% to 43.8% (median ADR, 24.1%) based on 5272 young adults receiving screening colonoscopies. Using 20% as an ADR level, the risks for metachronous adenoma and advanced adenoma were significantly higher in the low ADR group than the high ADR group (35.4% vs. 25.7%, P<0.001; 8.3% vs. 3.7%, P=0.001, respectively). However, using ADR level of 25%, the risk for metachronous neoplasia was similar in the high and low ADR groups in young adults according to screening colonoscopy. In subgroup analysis, similar findings were found in males, but not in females. CONCLUSIONS: Optimal target ADR may be different between younger and older populations, and the adoption of a 20% target ADR could be used as a performance indicator for young populations.

Probiotics Ameliorate Stool Consistency in Patients with Chronic Constipation: A Randomized, Double-Blind, Placebo-Controlled Study.

BACKGROUND/AIMS: The efficacy of probiotics for improving clinical symptoms, altering the fecal microbiota, and regulating serum immune cytokine levels was investigated in patients with irritable bowel syndrome-constipation (IBS-C) or functional constipation (FC). METHODS: A randomized, double-blind, placebo-controlled trial was conducted at Kyung Hee University Hospital between October 2016 and February 2017. Consecutive 18-75-year-old patients with diagnosis of IBS-C or FC (based on Rome IV criteria) consumed probiotics (3.0 × 108 CFU/g Streptococcus thermophilus MG510 and 1.0 × 108 CFU/g Lactobacillus plantarum LRCC5193) or a placebo daily for 4 weeks (weeks 1-4) and were followed up for a 4-week washout period without intervention (weeks 5-8). The primary outcomes of the study were Bristol Stool Form Scale and Complete Spontaneous Bowel Movements (CSBM). Efficacy was assessed by per protocol. RESULTS: Stool consistency measured by the Bristol Stool Form Scale was significantly better in the probiotic group (n = 88) than in the placebo group (n = 83) at 4 and 8 weeks (3.7 ± 1.1 vs. 3.1 ± 1.1 at 8 weeks, P = 0.002). No significant difference was found in CSBM. The quality of life was significantly better in the probiotic group than in the placebo group at 4 weeks (P = 0.044) and 8 weeks (P = 0.049). The relative abundance of L. plantarum among the fecal microbiomes was significantly greater in the probiotic group than in the placebo group at 4 weeks (P = 0.029). However, the levels of other microbiomes and of serum cytokines (IL-10/IL-12 ratio and TNF-α) did not differ significantly between the two groups. CONCLUSIONS: Probiotics significantly ameliorated stool consistency in patients with chronic constipation. In addition, the beneficial effect of L. plantarum on stool consistency remained after the probiotic supplementation was discontinued. The mechanism whereby probiotics benefit patients with chronic constipation should be clarified in further studies.

Age-adapted Variation in Screening Interval of Fecal Immunochemical Test May Improve its Participation and Colonoscopy Acceptance.

GOALS: We determined appropriate intervals for administering the fecal immunochemical test (FIT) and performance outcomes in an Asian national colorectal cancer (CRC) screening program. BACKGROUND: The optimal interval for FIT in CRC screening is unclear, especially in Asian populations. STUDY: Between January 2009 and December 2015, 13,480 individuals aged 50 years or older with an initial negative FIT result underwent 2 rounds of FIT screening at intervals of 1 (annual group, 5333), 2 (biennial group, 7363), or 3 years (triennial group, 784). Positive rates of FIT, colonoscopy acceptance, colonoscopy findings, and detection rates for CRC and advanced neoplasia were compared according to FIT intervals. RESULTS: The overall positivity rate of FIT in the second screening round was significantly higher in men and in older subjects than in the entire sample. Younger subjects were less likely to undergo annual FIT (36.0% vs. 46.4%, P<0.001). The colonoscopy acceptance rate was decreased in the biennial and triennial groups compared with an annual group among younger subjects (odds ratio, 0.56; 95% confidence interval, 0.33-0.95 for the biennial group vs. odds ratio, 0.19; 95% confidence interval, 0.03-1.37 for the triennial group). Detection rates for CRC and advanced neoplasia in the second round were significantly higher and accompanied by increased FIT screening intervals in older, but not younger subjects. CONCLUSIONS: Age-adapted variation in FIT screening intervals, such as annual screening for elderly subjects and biennial screening for younger subject, may improve FIT participation and colonoscopy acceptance.

Evaluation of scoring systems without endoscopic findings for predicting outcomes in patients with upper gastrointestinal bleeding.

BACKGROUND: Risk scoring systems are used to evaluate patients with upper gastrointestinal bleeding (UGIB). We compared Glasgow-Blatchford score (GBS), modified GBS (mGBS), and Pre-endoscopy Rockall score (Pre-E RS) for immediate application without endoscopic findings in predicting the need of interventions and the 30-day mortality in patients with UGIB. METHODS: Patients who visited the emergency room with UGIB from January 2007 to June 2016 were included. GBS, mGBS, and Pre-E RS were obtained for all patients. The area under the receiver-operating characteristic curves (AUC) was used to assess the accuracy of the scoring systems to determine the need for interventions and 30-day mortality. Also, we investigated the potential cutoff scores for predicting 30-day mortality and the need for interventions. RESULTS: In predicting the need for interventions, GBS (AUC = 0.727) and mGBS (AUC = 0.733) outperformed Pre-E RS (AUC = 0.564, P < 0.0001). In predicting 30-day mortality, Pre-E RS (AUC = 0.929) outperformed GBS (AUC = 0.664, P < 0.0001) and mGBS (AUC = 0.652, P < 0.0001). Based on AUC analyses of sensitivities and specificities, the optimal cutoff mGBS and GBS for the need for interventions was 9 (70.71% sensitivity, 89.35% specificity) and 9 (73.57% sensitivity, 82.90% specificity) respectively, and optimal cutoff Pre-E RS for 30-day mortality was 4 (88.0% sensitivity, 97.52% specificity). CONCLUSIONS: GBS and mGBS are considered to be moderately accurate in making an early decision about the need of interventions in patients with UGIB. Pre-E RS is considered to be highly accurate in early detection of patients at high risk for 30-day mortality without endoscopic findings. In addition, we suggested potential cutoff scores to predict the need of interventions for GBS and mGBS, and 30-day mortality for Pre-E RS. Further studies are needed to confirm the clinical applicability of results.

The Clinical Outcomes of Lower Gastrointestinal Bleeding Are Not Better than Those of Upper Gastrointestinal Bleeding.

The incidence of lower gastrointestinal bleeding (LGIB) is increasing; however, predictors of outcomes for patients with LGIB are not as well defined as those for patients with upper gastrointestinal bleeding (UGIB). The aim of this study was to identify the clinical outcomes and the predictors of poor outcomes for patients with LGIB, compared to outcomes for patients with UGIB. We identified patients with LGIB or UGIB who underwent endoscopic procedures between July 2006 and February 2013. Propensity score matching was used to improve comparability between LGIB and UGIB groups. The clinical outcomes and predictors of 30-day rebleeding and mortality rate were analyzed between the two groups. In total, 601 patients with UGIB (n = 500) or LGIB (n = 101) were included in the study, and 202 patients with UGIB and 101 patients with LGIB were analyzed after 2:1 propensity score matching. The 30-day rebleeding and mortality rates were 9.9% and 4.5% for the UGIB group, and 16.8% and 5.0% for LGIB group, respectively. After logistic regression analysis, the Rockall score (P = 0.013) and C-reactive protein (CRP; P = 0.047) levels were significant predictors of 30-day mortality in patients with LGIB; however, we could not identify any predictors of rebleeding in patients with LGIB. The clinical outcomes for patients with LGIB are not better than clinical outcomes for patients with UGIB. The clinical Rockall score and serum CRP levels may be used to predict 30-day mortality in patients with LGIB.

High-risk metachronous polyps are more frequent in patients with traditional serrated adenomas than in patients with conventional adenomas: a multicenter prospective study.

BACKGROUND AND AIMS: Although the malignant progression of serrated polyps has been clearly documented, the malignant potential of the traditional serrated adenoma (TSA) subtype has not been established. We compared the prevalence of metachronous polyps in surveillance colonoscopies between patients with TSA and those with conventional adenomas (CAs). METHODS: Four hundred twenty patients were diagnosed with TSAs by current diagnostic criteria at 10 tertiary care university hospitals in Korea from January 2003 to December 2005; 186 patients who received surveillance colonoscopy after removal of initial polyps were enrolled. During the same time period, 372 age- and sex-matched patients diagnosed with CAs were used as a control group. RESULTS: TSA patients had a significantly higher recurrence rate of colorectal polyps compared with CA patients (66.1% vs 43.5%, respectively). TSA patients had a greater number (3 vs 2) and larger size (8.6 ± 5.7 vs 6.3 ± 5.2 mm) of recurrent polyps compared with CA patients. TSA patients also had a higher rate of CA (54.8% vs 37.9%), serrated adenoma (14.0% vs. 0.8%), and hyperplastic polyp (33.3% vs. 13.7%) recurrence compared with CA patients. TSA patients had significantly greater odds of having a recurrent high-risk polyp than CA patients (odds ratio, 2.37; 95% confidence interval, 1.55-3.63). CONCLUSIONS: In comparison with patients with CAs, patients with TSAs have a higher metachronous occurrence rate of all polyp subtypes including CAs, serrated adenomas, and hyperplastic polyps. Moreover, the presence of TSAs is an independent predictor of a high-risk polyp occurrence.

Modulation of nicotinic receptor channels by adrenergic stimulation in rat pinealocytes.

Melatonin secretion from the pineal gland is triggered by norepinephrine released from sympathetic terminals at night. In contrast, cholinergic and parasympathetic inputs, by activating nicotinic cholinergic receptors (nAChR), have been suggested to counterbalance the noradrenergic input. Here we investigated whether adrenergic signaling regulates nAChR channels in rat pinealocytes. Acetylcholine or the selective nicotinic receptor agonist 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP) activated large nAChR currents in whole cell patch-clamp experiments. Norepinephrine (NE) reduced the nAChR currents, an effect partially mimicked by a ß-adrenergic receptor agonist, isoproterenol, and blocked by a ß-adrenergic receptor antagonist, propranolol. Increasing intracellular cAMP levels using membrane-permeable 8-bromoadenosine (8-Br)-cAMP or 5,6-dichlorobenzimidazole riboside-3',5'-cyclic monophosphorothioate (cBIMPS) also reduced nAChR activity, mimicking the effects of NE and isoproterenol. Further, removal of ATP from the intracellular pipette solution blocked the reduction of nAChR currents, suggesting involvement of protein kinases. Indeed protein kinase A inhibitors, H-89 and Rp-cAMPS, blocked the modulation of nAChR by adrenergic stimulation. After the downmodulation by NE, nAChR channels mediated a smaller Ca(2+) influx and less membrane depolarization from the resting potential. Together these results suggest that NE released from sympathetic terminals at night attenuates nicotinic cholinergic signaling.

Correlations of C-reactive protein levels and erythrocyte sedimentation rates with endoscopic activity indices in patients with ulcerative colitis.

BACKGROUND: Accurate assessment of endoscopic severity is essential to the early detection of relapses and treatment of patients with ulcerative colitis (UC). However, the relationships between non-invasive biomarkers and invasive endoscopic severity indices remain poorly understood. METHODS: A total of 722 endoscopies in 552 patients were evaluated in this study. Endoscopic activity was assessed using five widely used endoscopic scoring systems: the Powell-Tuck assessment, Mayo Endoscopic Score, modified Baron Score, Rachmilewitz Endoscopic Activity Index, and Hanauer's Sigmoidoscopic Index. These five indices were compared with two non-invasive biomarkers, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels. RESULTS: The Pearson's correlation coefficients of CRP and ESR with endoscopic indices were r = 0.457 and 0.342 in the Powell-Tuck assessment, r = 0.503 and r = 0.402 in the Mayo Endoscopic Score, r = 0.507 and 0.408 in Hanauer's Sigmoidoscopic Index, r = 0.520 and 0.433 in the modified Baron Score, and r = 0.523 and 0.435 in the Rachmilewitz Endoscopic Activity Index. Sensitivity and specificity ranges for CRP and ESR were 50.5-53.3 % and 68.7-71.3 % and 85.1-87.2 % and 63.4-66.4 %, respectively, for the detection of endoscopic remission using the five endoscopic indices. CONCLUSIONS: CRP and ESR levels were modestly correlated with endoscopic activity indices in UC patients. However, the low sensitivities for detecting endoscopic remission suggest that CRP or ESR alone is not sufficient to reflect endoscopic severity accurately.

Demographic Characteristics and Economic Burden of Clostridioides difficile Infection in Korea: A Nationwide Population-Based Study after Propensity Score Matching.

Clostridioides difficile infection (CDI) poses a considerable threat to global public health. However, there have been insufficient propensity score-matched data on its demographic characteristics and economic burden. Using nationwide claims data, we assessed longitudinal changes in the demographic characteristics and economic burden of CDI between 2011 and 2019 after propensity score matching. We performed a regression analysis to compare the differences in the length of hospital stay and medical costs between patients with CDI and controls (gastroenteritis and colitis). The CDI hospitalization rate increased 2.9-fold between 2011 and 2019. The CDI group had higher comorbidity index scores and was more frequently diagnosed at tertiary hospitals and in the Seoul region than the control group (all p < 0.001). The annual incidence rate of CDI/10,000 persons significantly increased in both sexes and all age groups. The length of hospital stay and medical costs were 3.3-fold and 5.0-fold greater, respectively, in the CDI than in the control group (both p < 0.001). Although the length of hospital stay decreased, total medical costs increased in all age groups and both sexes between 2011 and 2019 (all p < 0.001). When compared with the control group, the CDI-attributable length of hospital stay and medical cost were greater by 15.3 days and KRW 3413 (×103), respectively, after matching. In conclusion, CDI incidence, particularly among the elderly population with comorbidities, has been increasing. In addition, the length of hospital stay and total medical costs of the CDI group were greater than those of the control group.