Early gastric cancer of young patients treated by endoscopic submucosal dissection: focusing on the different characteristics and prognosis of elderly patients.

BACKGROUND: A small portion of patients are diagnosed with early gastric cancer (EGC) and undergo endoscopic submucosal dissection (ESD) at a young age. However, their clinical outcomes are rarely known. AIM: We investigated to identify the feasibility and clinical outcomes of ESD for EGC focusing on young patients. METHODS: We analyzed the clinical characteristics and outscomes of patients who had undergone ESD for the treatment of EGC at < 50 years of age. We enrolled patients who had been diagnosed with EGC and had undergone ESD between 2006 and 2020. We divided them by age as follows: ≤ 50 and > 50 years into the young age (YA) and other age (OA) groups, respectively. RESULTS: Altogether, 1681 patients underwent ESD for EGC (YA group: 124 [7.4%], OA group: 1557 [92.6%]). The YA group had less severe atrophy and more undifferentiated (37.1% vs. 13.9%, P < 0.001) and diffuse type (25% vs. 7.7%, P < 0.001) histology. The curative resection rate was not significantly different between the groups. However, among 1075 patients who had achieved curative resection and had been followed-up for > 12 months, the YA group had a lower incidence of MGN (5.2% vs. 17.5%, P = 0.004) and MGC (2.6% vs. 10.9%, P = 0.019) than those exhibited by the OA group. The YA group was a significant negative predictor of MGN (odds ratio [OR]: 2.983, 95% confidence interval [CI] 1.060-8.393, P = 0.038), and marginally negative predictor in MGC (OR: 3.909, 95% CI: 0.939-16.281, P = 0.061). CONCLUSION: ESD is a favorable and effective therapeutic modality for EGC patients aged < 50 years, once curative resection is achieved.

Colonic stenting as a bridge to surgery for obstructive colon cancer: is it safe in the long term?

BACKGROUND: The placement of a self-expanding metal stent in patients with obstructive colon cancer is used as a bridge to surgery. However, due to a lack of consensus and insufficient data, the long-term oncologic outcomes after colonic SEMS placement remain unclear. We assessed the long-term oncologic outcomes and adverse effects of colonic stenting for malignant colonic obstruction. METHODS: We included 198 patients admitted to Korea University Anam Hospital between 2006 and 2014 for obstructive colon cancer, of whom 98 underwent SEMS placement as a bridge to surgery and 100 underwent direct surgery without stenting. The clinicopathologic characteristics, overall survival, and disease-free survival were compared. RESULTS: There were no significant differences in long-term oncologic outcomes between the two groups. The median follow-up durations were 61.55 and 58.64 months in the SEMS and DS groups, respectively. There were also no significant differences in the 5-year OS (77.4% vs. 74.2%, p = 0.691) and 5-year DFS (61.7% vs. 71.0%, p = 0.194) rates between the groups. However, the DS group had significantly more early postoperative complications (p = 0.002). CONCLUSIONS: Colonic SEMS deployment as a bridge to surgery did not negatively affect long-term oncologic outcomes when compared with DS. In addition, colonic stenting decreased early postoperative complications and reduced the time for patients to return to normal daily activities.

RNA-sequencing identification and validation of genes differentially expressed in high-risk adenoma, advanced colorectal cancer, and normal controls.

Distinct gene expression patterns that occur during the adenoma-carcinoma sequence need to be determined to analyze the underlying mechanism in each step of colorectal cancer progression. Elucidation of biomarkers for colorectal polyps that harbor malignancy potential is important for prevention of colorectal cancer. Here, we use RNA sequencing to determine gene expression profile in patients with high-risk adenoma treated with endoscopic submucosal dissection by comparing with gene expression in patients with advanced colorectal cancer and normal controls. We collected 70 samples, which consisted of 27 colorectal polyps, 24 cancer tissues, and 19 normal colorectal mucosa. RNA sequencing was performed on an Illumina platform to select differentially expressed genes (DEGs) between colorectal polyps and cancer, polyps and controls, and cancer and normal controls. The Kyoto Gene and Genome Encyclopedia (KEGG) and gene ontology (GO) analysis, gene-concept network, GSEA, and a decision tree were used to evaluate the DEGs. We selected the most highly expressed genes in high-risk polyps and validated their expression using real-time PCR and immunohistochemistry. Compared to patients with colorectal cancer, 82 upregulated and 24 downregulated genes were detected in high-risk adenoma. In comparison with normal controls, 33 upregulated and 79 downregulated genes were found in high-risk adenoma. In total, six genes were retrieved as the highest and second highest expressed in advanced polyps and cancers among the three groups. Among the six genes, ANAX3 and CD44 expression in real-time PCR for validation was in good accordance with RNA sequencing. We identified differential expression of mRNAs among high-risk adenoma, advanced colorectal cancer, and normal controls, including that of CD44 and ANXA3, suggesting that this cluster of genes as a marker of high-risk colorectal adenoma.

Endoscopic submucosal dissection using a detachable assistant robot: a comparative in vivo feasibility study (with video).

BACKGROUND: Appropriate tissue tension and clear visibility of the dissection area using traction are essential for effective and safe endoscopic submucosal dissection (ESD). We developed a robotic assistive traction device for flexible endoscopy and compared its safety and efficiency in ESD between experienced and novice endoscopists. METHODS: Robotic ESD was performed by experienced and novice endoscopist groups (n = 2, each). The outcomes included time to complete each ESD step, total procedure time, size of the dissected mucosa, rate of en bloc resection, and major adverse events. Furthermore, incision and dissection speeds were compared between groups. RESULTS: Sixteen gastric lesions were resected from nine live pigs. The submucosal incision speed was significantly faster in the expert group than in the novice group (P = 0.002). There was no significant difference in the submucosal dissection speed between the groups (P = 0.365). No complications were reported in either group. CONCLUSIONS: When the robot was assisting in the ESD procedure, the dissection speed improved significantly, especially in the novice surgeons. Our robotic device can provide simple, effective, and safe multidirectional traction during ESD.

Dipeptidyl-peptidase-4 (DPP-4) inhibitor ameliorates 5-flurouracil induced intestinal mucositis.

BACKGROUND: Chemotherapy-induced alimentary mucositis (AM) is difficult to prevent and treatment is rarely effective. Recent study have been showed that glucagon-like peptide (GLP)-1 and GLP-2 has protective in chemotherapy-induced AM. While the DPP-4 enzyme degrades this GLP-1, the DPP-4 inhibitor blocks the degradation process and raises the concentration of GLP-1. This study aimed to assess the role of DPP-4 inhibitor, a well-known hypoglycemic agent, on chemotherapy-induced AM. METHODS: Twenty-four 6-week-old male C57BL/6 mice were divided into 4 groups: control, 5-fluorouracil (5-FU), DPP-4 inhibitor, and saline (DPP-4i), and DPP-4 inhibitor and 5-FU (DPP-4i + 5-FU). Mucositis was induced by intraperitoneal injection of 5-FU (400 mg/kg). DPP-4 inhibitor (50 mg/kg) was administered orally for four days starting the day before 5-FU administration. Post 72 h of 5-FU injection, mice were sacrificed and body weight change, diarrhea score, villus height, villus/crypt ratio, histologic characteristics including goblet cell count, and mRNA expression of inflammatory cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6, were assessed. RESULTS: Daily body weight change was not statistically significant between the 5-FU and the DPP-4i + 5-FU group (P = 0.571). Diarrhea score was significantly different between these two groups (P = 0.033). In the 5-FU group, the villus height was not maintained well, the epithelial lining was irregular, and inflammatory cell infiltration was observed. Goblet cell count in the DPP-4i + 5-FU group was significantly higher than in the 5-FU group (P = 0.007). However, in the DPP-4i + 5-FU group, the villus height, epithelial lining, and crypt structure were better maintained than in the 5-FU group. Compared with the control group, mRNA expression of TNF-α was significantly up-regulated in the 5-FU group. Moreover, mRNA expression of TNF-α in the DPP-4i + 5-FU group was down-regulated compared to the 5-FU group. However, IL-6 in the 5-FU group was significantly down-regulated compared to the control, there was no significant difference in expression of IL-6 between the 5-FU and DPP4i + 5-FU group. CONCLUSION: DPP-4 inhibitor can improve 5-FU induced AM and, therefore, has potential as an alternative treatment for chemotherapy-induced AM.

A randomized controlled trial comparing the efficacy of 1-L polyethylene glycol solution with ascorbic acid plus prucalopride versus 2-L polyethylene glycol solution with ascorbic acid for bowel preparation.

OBJECTIVES: Bowel cleansing is a major patient complaint during colonoscopy. Adding laxatives to the bowel preparation is effective in replacing a portion of bowel preparation solution and reducing its volume. Prucalopride is a serotonin receptor agonist that stimulates gastrointestinal motility and provides propulsive force for defecation. This study aimed to compare 1 L polyethylene glycol (PEG) with ascorbic acid (Asc) plus 2 mg prucalopride (1LP/AP) and 2 L PEG with Asc (2LP/A) for colonoscopy preparation with respect to bowel-cleansing quality and side effects. METHODS: A single-center, randomized, prospective study was conducted with 260 outpatients administered either 1LP/AP or 2LP/A. The primary endpoint was bowel preparation quality, which was evaluated using the Boston Bowel Preparation Scale and Aronchick Bowel Preparation Scale, and the secondary endpoints were patient tolerability and acceptability, assessed by a questionnaire-based survey. RESULTS: The adequate bowel preparation rates were 88.5% and 83.1% in the 2LP/A and 1LP/AP groups, respectively, and the efficacy of 1LP/AP was equivalent to the control regimen (p=.216). Other colonoscopic variables including adenoma detection rate were similar in both groups. Patient tolerability and acceptability were not significantly different, but patients in the 1LP/AP group were more willing to repeat the same regimen (p=.039). CONCLUSIONS: Bowel preparation quality with 1LP/AP was equivalent to that with 2LP/A, which did not increase the occurrence of side effects, but it reduced the volume of the solution ingested, and increased patient satisfaction.

Flavobacterium knui sp. nov., a novel member of the family Flavobacteriaceae.

A Gram-stain negative, non-motile, rod-shaped bacterial strain, designated 2-56T, was isolated from water and characterized taxonomically using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain 2-56T belongs to the family Flavobacteriaceae in the phylum Bacteroidetes and is closely related to Flavobacterium paronense KNUS1T (98.4%) and Flavobacterium collinsense 4-T-2T (96.7%). The G + C content of the genomic DNA of strain 2-56T was 33.4 mol%. The isolate contained MK-6 as the predominant respiratory quinone, and iso-C15:1 G (15.9%), iso-C15:0 (15.8%), iso-C17:0 3-OH (10.7%), and iso-C15:0 3-OH (9.6%) were the major fatty acids. The major polar lipids were phosphatidylethanolamine and an unidentified lipid. The phenotypic and chemotaxonomic data support the affiliation of strain 2-56T with the genus Flavobacterium. However, the DNA-DNA relatedness between the isolate and F. paronense and F. collinsense were 35.7 and 21.5%, respectively, clearly showing that strain 2-56T is not related to them at the species level. Strain 2-56T could be clearly differentiated from its close neighbours on the basis of its phenotypic, genotypic and chemotaxonomic features. Therefore, strain 2-56T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium knui sp. nov. is proposed. The type strain is 2-56T (= KCTC 62061T = JCM 32247T).

Comparison of a split-dose bowel preparation with 2 liters of polyethylene glycol plus ascorbic acid and 1 liter of polyethylene glycol plus ascorbic acid and bisacodyl before colonoscopy.

BACKGROUND AND AIMS: Recently, a low-volume polyethylene glycol formulation containing ascorbic acid (PEG-Asc) has proven as safe and effective as traditional 4-L PEG solutions for colonoscopy preparation. However, currently available aqueous purgative formulations are poorly tolerated. The aim of this study was to compare a split-dose 2-L PEG-Asc formulation and a 1-L PEG-Asc formulation with bisacodyl (10 mg) to determine the quality of bowel cleansing and patient tolerability. METHODS: A single-center, randomized, observer-blinded study was performed between May 2015 and September 2015. Two hundred outpatients referred for colonoscopy were prospectively enrolled and assigned to either the split-dose 2-L PEG-Asc group or the 1-L PEG-Asc with bisacodyl 10-mg group. The Boston Bowel Preparation Scale (BBPS) and Aronchick Bowel Preparation Scale (ABPS) were used to evaluate bowel cleansing. The tolerability of the regimens and satisfaction of patients was determined based on a questionnaire. RESULTS: Two hundred patients received either 2-L PEG-Asc or 1-L PEG-Asc with bisacodyl. Regarding colon cleansing outcome (BBPS and ABPS), the 1-L PEG-Asc with bisacodyl group showed similar but non-inferior results compared with the 2-L PEG-Asc group on both BBPS (6.92 ± 1.63 vs 6.57 ± 1.37; P = .103) and ABPS (96% vs 95%; P = 1.000) scales. Tolerability was similar for both 1-L PEG-Asc with bisacodyl and 2-L PEG-Asc. CONCLUSIONS: 1-L PEG-Asc is a suitable alternative to low-volume bowel preparation for colonoscopy. Our study showed that the 1-L PEG-Asc plus bisacodyl preparation has comparable tolerability and results in adequate colon cleansing. Bowel preparation with bisacodyl and 1-L PEG-Asc is a suitable alternative to low-volume bowel preparation for colonoscopy. (Clinical trial registration number: NCT02980562.).

Clinical Evaluation of Rapid Diagnostic Test Kit Using the Polysaccharide as a Genus-Specific Diagnostic Antigen for Leptospirosis in Korea, Bulgaria, and Argentina.

Leptospirosis, a zoonotic disease that is caused by many serovars which are more than 200 in the world, is an emerging worldwide disease. Accurate and rapid diagnostic tests for leptospirosis are a critical step to diagnose the disease. There are some commercial kits available for diagnosis of leptospirosis, but the obscurity of a species- or genus-specific antigen of pathogenic Leptospira interrogans causes the reduced sensitivity and specificity. In this study, the polysaccharide derived from lipopolysaccharide (LPS) of nonpathogenic Leptospira biflexa serovar patoc was prepared, and the antigenicity was confirmed by immunoblot and enzyme linked immunosorbent assay (ELISA). The performance of the rapid diagnostic test (RDT) kit using the polysaccharide as a diagnostic antigen was evaluated in Korea, Bulgaria and Argentina. The sensitivity was 93.9%, 100%, and 81.0% and the specificity was 97.9%, 100%, and 95.4% in Korea (which is a rare region occurring with 2 serovars mostly), Bulgaria (epidemic region with 3 serovars chiefly) and Argentina (endemic region with 19 serovars mainly) respectively. These results indicate that this RDT is applicable for global diagnosis of leptospirosis. This rapid and effective diagnosis will be helpful for diagnosis and manage of leptospirosis to use and the polysaccharide of Leptospira may be called as genus specific antigen for diagnosis.

Clinical Evaluation of Rapid Diagnostic Test Kit for Scrub Typhus with Improved Performance.

Diagnosis of scrub typhus is challenging due to its more than twenty serotypes and the similar clinical symptoms with other acute febrile illnesses including leptospirosis, murine typhus and hemorrhagic fever with renal syndrome. Accuracy and rapidity of a diagnostic test to Orientia tsutsugamushi is an important step to diagnose this disease. To discriminate scrub typhus from other diseases, the improved ImmuneMed Scrub Typhus Rapid Diagnostic Test (RDT) was evaluated in Korea and Sri Lanka. The sensitivity at the base of each IgM and IgG indirect immunofluorescent assay (IFA) in Korean patients was 98.6% and 97.1%, and the specificity was 98.2% and 97.7% respectively. The sensitivity and specificity for retrospective diagnosis at the base of IFA in Sri Lanka was 92.1% and 96.1%. ImmuneMed RDT was not reactive to any serum from seventeen diseases including hemorrhagic fever with renal syndrome (n = 48), leptospirosis (n = 23), and murine typhus (n = 48). ImmuneMed RDT shows superior sensitivity (98.6% and 97.1%) compared with SD Bioline RDT (84.4% at IgM and 83.3% at IgG) in Korea. The retrospective diagnosis of ImmuneMed RDT exhibits 94.0% identity with enzyme-linked Immunosorbent assay (ELISA) using South India patient serum samples. These results suggest that this RDT can replace other diagnostic tests and is applicable for global diagnosis of scrub typhus. This rapid and accurate diagnosis will be beneficial for diagnosing and managing scrub typhus.

Continuous exposure to 60 Hz magnetic fields induces duration- and dose-dependent apoptosis of testicular germ cells.

To evaluate duration- and dose-dependent effects of continuous exposure to a 60 Hz magnetic field (MF) on the testes in mice, BALB/c male mice were exposed to a 60 Hz MF at 100 µT for 24 h a day for 2, 4, 6, or 8 weeks, and at 2, 20, or 200 µT for 24 h a day for 8 weeks. Any exposures to MF did not significantly affect body or testicular masses. However, the apoptotic cells among testicular germ cells were increased duration-dependent at exposures of 100 µT for 6 and 8 weeks and dose-dependent at exposures of 20 and 200 µT for 8 weeks. The number of sperm in epididymis and the diameter of seminiferous tubule decreased in mice exposed to 100 and 200 µT for 8 weeks, respectively. To induce the apoptosis of testicular germ cell in mice, the minimum dose is 20 µT at continuous exposure to a 60 Hz MF for 8 weeks and the minimum duration is 6 weeks at continuous exposure of 100 µT. Taken together, these results suggest that continuous exposure to a 60 Hz MF might affect, duration- and dose-dependent biological processes including apoptotic cell death and spermatogenesis in the male reproductive system of mice.

Current status and clinical outcome of endoscopic hemostatic powder in gastrointestinal bleeding: a retrospective multicenter study.

Background/Aims: Few multicenter studies have investigated the efficacy of hemostatic powders in gastrointestinal (GI) bleeding. We aimed to investigate the clinical outcomes of hemostatic powder therapy and the independent factors affecting rebleeding rates. Methods: We retrospectively recruited patients who underwent a new hemostatic adhesive powder (UI-EWD; Next-Biomedical) treatment for upper and lower GI bleeding between January 1, 2020 and March 1, 2023. We collected patients' medical records and bleeding lesions. The primary outcomes were clinical and technical success rates, and the secondary outcomes were early, delayed, and refractory bleeding, mortality, and factors affecting early rebleeding rates. Results: This study enrolled 135 patients (age: 67.7±13.6 years, male: 74.1%) from five hospitals. Indications for UI-EWD were peptic ulcers (51.1%), post-procedure-related bleeding (23.0%), and tumor bleeding (19.3%). The clinical and technical success rates were both 97%. The early, delayed, and refractory rebleeding rates were 19.3%, 11.1%, and 12.8%, respectively. Initially elevated blood urea nitrogen (BUN) levels (p=0.014) and Forrest classification IA or IB compared with IIA or IIB (p=0.036) were factors affecting early rebleeding. Conclusions: UI-EWD showed high clinical and technical success rates; however, rebleeding after UI-EWD therapy in patients with initially high BUN levels and active bleeding, according to the Forrest classification, should be considered.

Prospective Evaluation of a New Liquid-Type Rapid Urease Test Kit for Diagnosis of Helicobacter pylori.

BACKGROUND/AIMS: Rapid and accurate diagnostic tools are essential for the timely recognition of Helicobacter pylori (H. pylori) in clinical practice. The rapid urease test (RUT) is a comparatively accurate and time-saving method recommended as a first-line diagnostic test. The primary objective of conducting the RUT is to obtain rapid results, thus enabling the initiation of an eradication therapy based on clarithromycin resistance testing. This study aimed to assess the reaction time and accuracy of a new liquid-type RUT. METHOD: In this prospective study, consecutive dyspeptic or check-up patients referred to our clinic for endoscopy were assessed to evaluate the rapidity and accuracy of a novel liquid-type RUT (Helicotest®, WON Medical, Bucheon, Republic of Korea) compared with another commercial RUT kit (HP kit, Chong Kun Dang, Seoul, Republic of Korea) and a real-time quantitative PCR-based assay (Seeplex® H.pylori-ClaR Detection, Seegene, Republic of Korea). RUTs were analyzed at 10 min, 30 min, 60 min, and 120 min. RESULTS: Among the 177 enrolled patients, 38.6% were infected with H. pylori. The positivity rates of the liquid-type RUT were 26.1, 35.8, 39.2%, and 41.5% at 10, 30, 60, and 120 min, respectively. When compared with the HP kit test, the time needed to confirm positivity was significantly reduced by 28.6 min (95% CI, 16.60-39.73, p < 0.0001). Helicotest® had a greater accuracy (96.02 ± 1.47), sensitivity (98.53 ± 1.46) and NPV (99.03 ± 0.97) compared to the HP kit. CONCLUSIONS: Compared to the commonly used RUT, the new liquid-type RUT presented faster and reliable results. Such findings could improve H. pylori treatment outcomes, particularly in outpatient clinical settings.

Improvement of the diagnostic sensitivity of scrub typhus using a mixture of recombinant antigens derived from Orientia tsutsugamushi serotypes.

Diagnosis of scrub typhus is difficult because its symptoms are very similar to other acute febrile illnesses, such as leptospirosis, murine typhus, and other viral hemorrhagic fevers. To differentiate scrub typhus from other acute febrile diseases, a rapid and reliable serological diagnosis is important. We have developed a chimeric recombinant antigen cr56 and two other recombinant antigens, r21 and kr56, from various serotypes of Orientia tsutsugamushi. They were tested for the detection of antibodies against O. tsutsugamushi in the patient's serum samples using enzyme-linked immunosorbent assay (ELISA) and dot-blot analyses. As of conventional immunofluorescence assay (IFA), when the mixture of these three recombinant antigens was used, both sensitivity and specificity of the recombinant antigens were increased up to 98% in IgM and IgG at ELISA and dot blotting. Additionally, both sensitivity and specificity by detection of IgM and IgG antibodies at rapid diagnostic test (RDT), using the mixture of three antigens and gold conjugated antibodies, were 99%. Our results suggest the use of mixture of these recombinant antigen proteins in ELISA or RDT is suitable as a diagnostic test for scrub typhus.

Re-bleeding and all-cause mortality risk in non-variceal upper gastrointestinal bleeding: focusing on patients receiving oral anticoagulant therapy.

OBJECTIVE: Non-variceal upper gastrointestinal bleeding (NVUGIB) in patients receiving oral anticoagulants (OACs) may be fatal; however, little is known about re-bleeding and all-cause mortality after successful hemostasis. We investigated the clinical characteristics and risk factors for re-bleeding and death after successful hemostasis. METHODS: Patients receiving OACs and diagnosed with NVUGIB between 2007 and 2021 were enrolled. All NVUGIB incidents were confirmed if definite bleeding in the upper gastrointestinal tract was detected via esophagogastroduodenoscopy. RESULTS: A total of 132 patients receiving OACs were diagnosed with NVUGIB. Males were the majority (72, 54.5%), and bleeding was detected mostly in the stomach (99, 75%) and was most often due to peptic ulcers (PU) (88, 66.7%). After successful hemostasis of index NVUGIB, 40 patients (30.3%) experienced re-bleeding. Among them, 15 (37.5%) died, and among those, 3 (2.3%) were related to re-bleeding. Multivariate analysis revealed that duodenal bleeding (odds ratio [OR]: 3.305; 95% confidence interval [CI]: 1.152-9.479, p = 0.026) and Charlson comorbidity index score (CCI) (OR: 1.22; 95% CI: 1.052-1.419, p = 0.009) were significant risk factors for re-bleeding. Index albumin levels (OR: 0.134; 95% CI: 0.035-0.506, p = 0.003), previous PU or upper gastrointestinal bleeding (UGIB) history (OR: 4.626; 95% CI: 1.375-15.567, p = 0.013), and CCI (OR: 1.293; 95% CI: 1.058-1.581, p = 0.012) were related all-cause mortality. CONCLUSION: CCI and duodenal bleeding are risk factors for re-bleeding in patients with NVUGIB who were receiving OACs, while low index albumin levels and previous PU and UGIB history are associated with all-cause mortality.

While taking oral anticoagulants can offer various benefits, the risks of re-bleeding and all-cause mortality remain.A Charlson comorbidity index of higher than 4.5 and duodenal bleeding occurring while receiving oral anticoagulants increase the risk of rebleeding.Hypoalbuminemia <3.25 g/dL, history of peptic ulcer or upper gastrointestinal bleeding and Charlson comorbidity index were significant risk factors for all-cause mortality.

Recurrent Non-Variceal Upper Gastrointestinal Bleeding among Patients Receiving Dual Antiplatelet Therapy.

BACKGROUND: Patients undergoing dual antiplatelet therapy (DAPT) may experience recurrent gastrointestinal bleeding (GIB). We investigated the clinical characteristics and risk factors for recurrent non-variceal upper gastrointestinal bleeding (NVUGIB) in patients who had experienced NVUGIB while receiving DAPT. METHODS: We enrolled patients diagnosed with NVUGIB while receiving DAPT between 2006 and 2020. Definite bleeding was confirmed by esophagogastroduodenoscopy in all NVUGIB patients. RESULTS: A total of 124 patients were diagnosed with NVUGIB while receiving DAPT. They were predominantly male (n = 103, 83.1%), bleeding mostly from the stomach (n = 94, 75.8%) and had peptic ulcers (n = 72, 58.1%). After the successful hemostasis of NVUGIB, 36 patients (29.0%) experienced at least one episode of recurrent upper GIB, 19 patients (15.3%) died, and 7 (5.6%) patients had a bleeding-related death. Multivariate analysis showed that age was a significant factor for re-bleeding (odds ratio [OR], 1.050; 95% confidence interval [CI]: 1.001-1.102; p-value: 0.047), all-cause mortality (OR, 1.096; 95% CI: 1.020-1.178, p = 0.013), and re-bleeding-related mortality (OR, 1.187; 95% CI: 1.032-1.364, p-value: 0.016). In Kaplan-Meier analysis, the cumulative probabilities of re-bleeding, death, and bleeding-related death were significantly higher in patients aged 70 and older (p = 0.008, <0.001, and 0.009, respectively). CONCLUSIONS: Clinicians should be cautious about re-bleeding and mortality in elderly patients who experience NVUGIB while receiving DAPT.

Fracture Resistance of Monolithic Zirconia Crowns Depending on Different Marginal Thicknesses.

Under some clinical conditions, the preparation of crowns of limited marginal thickness is inevitable. In such situations, it is questionable whether the same ideal preparation criteria can be applied equally. Since there are only a small number of studies focusing on the fracture resistance with respect to the marginal thickness, there is a need for a study evaluating whether zirconia crowns of limited marginal thickness are clinically acceptable. The purpose of this study is to evaluate the fracture resistance of monolithic zirconia crowns of limited marginal thickness in the posterior area. Methods: Abutments and CAD/CAM zirconia crowns with a marginal thickness of 1.0 mm were set as the control group, while experimental groups A, B, and C possessed reduced marginal thicknesses of 0.8 mm, 0.6 mm, and 0.4 mm, respectively (n = 10 per group). Resin-based abutment dies and monolithic zirconia crowns were fabricated using the CAD/CAM technique, and a universal testing machine was used to measure the fracture load value. Fractured specimens were examined with a scanning electron microscope. The data were analyzed using a one-way ANOVA and Bonferroni post hoc test (p < 0.05). Results: The means and standard deviations of the fracture load values of the control group and the three experimental groups were as follows: control group (1.0 mm): 3090.91 ± 527.77 N; group A (0.8 mm): 2645.39 ± 329.21 N; group B (0.6 mm): 2256.85 ± 454.15 N; group C (0.4 mm): 1957.8 ± 522.14 N. Conclusions: The crowns fabricated with a CAD/CAM zirconia block with limited marginal thicknesses of 0.6 mm and 0.4 mm showed significantly lower fracture resistance values compared to those with the recommended margin thickness of 1.0 mm.