Repeated photodynamic therapy using a chlorin e6-embedded device to prolong the therapeutic effects on obesity.

OBJECTIVE: This study aimed to investigate the efficacy and safety of repeated photodynamic therapy (PDT) with a chlorin e6 (Ce6)-embedded intragastric satiety-inducing device (ISD) to maintain therapeutic effects of obesity in a juvenile pig. METHODS: The Ce6-embedded ISD was fabricated with a dipping method. Twelve pigs were divided into four groups of three and were administered control, single, biweekly, or weekly PDT, respectively. The therapeutic effects were assessed by comparing the results of phototoxicity, endoscopy, fluoroscopy, hormone and weight changes, and histological examination. RESULTS: The percentage of total body weight gain was significantly suppressed in PDT-treated pigs compared with control pigs (all p < 0.001). This suppression persisted in the repeated PDT groups, but percentage of total body weight gain gradually increased when PDT was stopped. Ghrelin levels in the PDT-treated groups were significantly lower and leptin levels were significantly higher than those in the control group (all p < 0.05). Inflammatory cell infiltration, collagen, TUNEL, and anti-ghrelin-positive deposition in the weekly group were significantly higher than those in the control, single, and biweekly groups (all p < 0.01). CONCLUSIONS: Repeated and periodic PDT was technically feasible and safe and successfully maintained the therapeutic effects against obesity while eliminating the indwelling time and reducing ISD-related complications in pigs.

Preparation and Properties of Mechanically Robust, Colorless, and Transparent Aramid Films.

In this study, various diamine monomers were used to synthesize aramid polymer films via a low-temperature solution condensation reaction with diacid chloride. For diamines with relatively high basicity, the reaction system became opaque because amine salt formation inhibited polymer synthesis. Meanwhile, low-basicity diamines with strong electron-withdrawing groups, such as CF3 and sulfone, were smoothly polymerized without amine salt formation to provide highly viscous solutions. The acid byproduct HCl generated during polymerization was removed by adding propylene oxide to the reaction vessel and converting the acid into highly volatile inert substances. The resulting solutions were used as varnishes without any additional purification, and polymer films with an excellent appearance were easily obtained through a conventional casting and convection drying process. The films neither tore nor broke when pulled or bent by hand; furthermore, even when heated up to 400 °C, they did not decompose or melt. Moreover, polymers prepared from 2,2-bis(trifluoromethyl)benzidine (TFMB) and bis(4-aminophenyl)sulfone (pAPS) did not exhibit glass transition until decomposition. The prepared polymer films showed a high elastic modulus of more than 4.1 GPa and a high tensile strength of more than 52 MPa. In particular, TFMB-, pAPS-, and 2,2-bis(4-aminophenyl)hexafluoropropane-based polymer films were colorless and transparent, with very high light transmittances of 95%, 96%, and 91%, respectively, at 420 nm and low yellow indexes of 2.4, 1.9, and 4.3, respectively.

Clinical outcomes of argon plasma coagulation for the treatment of gastric low-grade dysplasia.

BACKGROUND AND AIMS: Argon plasma coagulation (APC) could be considered a treatment modality for small gastric low-grade dysplasia (LGD) instead of endoscopic resection. Our study investigated the clinical outcomes of APC for treating gastric LGD and associated variables with local recurrence. METHODS: This study included 911 patients who underwent APC for gastric neoplasms at the tertiary hospital from July 2007 to March 2022 with a minimal follow-up of 12 months. Of these patients, 112 without any information about Helicobacter pylori infection status, 164 who underwent APC for salvage therapy, 5 with high-grade dysplasia, and 12 with cancer were excluded. Through a retrospective review of medical data, the clinical outcomes and variables associated with the local recurrence were analyzed. RESULTS: A total of 618 patients with LGD (median age, 64 years) were followed up for a median of 30 months, and local recurrence has happened in 21 (3.4%) patients. Multivariate analysis showed that lesion size (hazard ratio, 1.06; 95% confidential interval, 1.01-1.12) was associated with the local recurrence. Among 557 lesions smaller than 10 mm, local recurrence was found in 14 (2.6%) cases, and local recurrence was found in 7 (9.5%) cases of 109 tumors larger than 10 mm (P < .004). CONCLUSIONS: In gastric LGD smaller than 10 mm without scars, APC is a good treatment modality in place of endoscopic resection. However, when a lesion is larger, APC should be selected carefully with close monitoring.

Localized Photodynamic Therapy Using a Chlorin e6-Embedded Silicone-Covered Self-Expandable Metallic Stent as a Palliative Treatment for Malignant Esophageal Strictures.

Localized photodynamic therapy (PDT) uses a polymeric-photosensitizer (PS)-embedded, covered self-expandable metallic stent (SEMS). PDT is minimally invasive and a noteworthy potential alternative for treating esophageal strictures, where surgery is not a viable option. However, preclinical evidence is insufficient, and optimized irradiation energy dose ranges for localized PDT are unclear. Herein, we validated the irradiation energy doses of the SEMS (embedded in a PS using chlorin e6 [Ce6] and covered in silicone) and PDT-induced tissue changes in a rat esophagus. Cytotoxicity and phototoxicity in the Ce6-embedded SEMS piece with laser irradiation were significantly higher than that of the silicone-covered SEMS with or without laser and the Ce6-embedded silicone-covered SEMS without laser groups (all p < 0.001). Moreover, surface morphology, atomic changes, and homogeneous coverage of the Ce6-embedded silicone-covered membrane were confirmed. The ablation range of the porcine liver was proportionally increased with the irradiation dose (all p < 0.001). The ablation region was identified at different irradiation energy doses of 50, 100, 200, and 400 J/cm2. The in vivo study in the rat esophagus comprised a control group and 100, 200, and 400 J/cm2 energy-dose groups. Finally, histology and immunohistochemistry (TUNEL and Ki67) confirmed that the optimized Ce6-embedded silicone-covered SEMS with selected irradiation energy doses (200 and 400 J/cm2) effectively damaged the esophageal tissue without ductal perforation. The polymeric PS-embedded silicone-covered SEMS can be easily placed via a minimally invasive approach and represents a promising new approach for the palliative treatment of malignant esophageal strictures.

Roll-to-Roll Gravure Coating of PVDF on a Battery Separator for the Enhancement of Thermal Stability.

The polyethylene lithium-ion battery separator is coated with a polymer by means of a roll-to-roll (R2R) gravure coating scheme to enhance the thermal stability. The polyvinylidene fluoride (PVDF) or polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) is gravure-coated, and the pores are fabricated based on online nonsolvent-induced phase separation (NIPS). N-methylpyrrolidone is used as a solvent, and deionized water or a methanol mixture thereof is exploited as a nonsolvent in NIPS. Scanning electron microscopy confirms that the polymer film is formed and that the pores are well developed. The thermal shrinkage decreased by 20.0% and 23.2% compared to that of the bare separator due to the coating of PVDF and PVDF-HFP, respectively. The R2R gravure coating scheme is proven to be fully functional to tailor the properties of lithium-ion battery separators.

Mechanically Enhanced Soft Contact Lenses from Photodimerization Cross-Linking.

In this study, we synthesized three novel acrylic monomers with a cinnamate group. We then mixed each monomer with 2-hydroxyethyl methacrylate (HEMA) to prepare soft contact lenses through bulk polymerization. Fourier transform infrared (FT-IR) and UV spectral analyses confirmed that the cinnamate group in the polymer undergoes a photodimerization reaction via UV irradiation. After UV curing, the present lenses stably maintained their shapes even in a water-swollen state and showed significantly improved mechanical properties compared to conventional lenses manufactured using a cross-linking agent. These lenses showed slightly lower water contact angles than the conventional lenses, although the water content was slightly reduced. The present photodimerization cross-linking method was found to be useful in reducing the tearability of soft lenses.

Comparison of Diagnosis of Esophageal Motility Disorders by Chicago Classification Versions 3.0 and 4.0.

Background/Aims: We aim to investigate the diagnostic accuracy and differences between Chicago classification version 3.0 (CC v3.0) and 4.0 (CC v4.0). Methods: Patients who underwent high-resolution esophageal manometry (HRM) for suspected esophageal motility disorders were prospectively recruited between May 2020 and February 2021. The protocol of HRM studies included additional positional change and provocative testing designed by CC v4.0. Results: Two hundred forty-four patients were included. The median age was 59 (interquartile range, 45-66) years, and 46.7% were males. Of these, 53.3% (n = 130) and 61.9% (n = 151) were categorized as normalcy by CC v3.0 and CC v4.0, respectively. The 15 patients diagnosed of esophagogastric junction outflow obstruction (EGJOO) by CC v3.0 was changed to normalcy by position (n = 2) and symptom (n = 13) by CC v4.0. In seven patients, the ineffective esophageal motility (IEM) diagnosis by CC v3.0 was changed to normalcy by CC v4.0. The diagnostic rate of achalasia increased from 11.1% (n = 27) to 13.9% (n = 34) by CC v4.0. Of patients diagnosed IEM by CC v3.0, 4 was changed to achalasia based on the functional lumen imaging probe (FLIP) results by CC v4.0. Three patients (2 with absent contractility and 1 with IEM in CC v3.0) were newly diagnosed with achalasia using a provocative test and barium esophagography by CC v4.0. Conclusions: CC v4.0 is more rigorous than CC v3.0 for the diagnosis of EGJOO and IEM and diagnoses achalasia more accurately by using provocative tests and FLIP. Further studies on the treatment outcomes following diagnosis with CC v4.0 are needed.

Photoactive intragastric satiety-inducing device using polymeric photosensitizers for minimally invasive weight loss treatment.

An intragastric satiety-inducing device (ISD) located in the stomach induce satiety and fullness in the absence of food by continuously pressing on the distal esophagus and cardia of the stomach. To improve the therapeutic function of ISD, Chlorin e6 (Ce6) was embedded in a disk portion of ISD, generating reactive oxygen species and stimulating endocrine cells under the laser irradiation. Since Ce6 has remarkable light efficiency but poor solubility in various solvents, it is essential to use a polymeric photosensitizer and optimize a suitable coating solution composition. Methoxy polyethylene glycol-Ce6 was uniformly coated and the spontaneous release amount of the Ce6 from the device could be reduced, which induced photo-responsive cell death and reduced ghrelin levels in vitro. In mini pigs operated single therapy (PDT or ISD) or combination therapy (Photoreactive ISD), there were differences in body weight (control: 28% vs. Photoreactive ISD: 4%, P < 0.001), ghrelin (control: 4% vs. Photoreactive ISD: 35%, P < 0.001), and leptin levels (control: 8% vs. Photoreactive PDT: 35%, P < 0.001) at 4 weeks.

Clinical outcomes of Dieulafoy's lesion compared with peptic ulcer in upper gastrointestinal bleeding.

BACKGROUND AND AIM: Although Dieulafoy's lesion (DL) is an important cause of nonvariceal upper gastrointestinal (GI) bleeding, few studies have investigated the clinico-epidemiological outcomes due to its rarity. Here, we investigated clinical features of upper GI bleeding caused by peptic ulcer (PU) or DL and compared endoscopic treatment outcomes. METHODS: Patients with upper GI bleeding resulting from PU or DL who visited emergency room between January 2013 and December 2017 were eligible. Clinical features and treatment outcomes were retrospectively investigated. RESULTS: Overall, 728 patients with upper GI bleeding due to PU (n = 669) and DL (n = 59) were enrolled. The median age was 64 years (interquartile range [IQR], 56-75 years), and 74.3% were male. Endoscopic intervention was performed in 53.7% (n = 359) and 98.3% (n = 58) of the PU and DL groups, respectively (P < 0.0001). Patients were matched by sex, age, body mass index, comorbidity, and past medical history, and 190 PU and 52 DL were finally selected. The rebleeding rates within 7 (7.37% vs 17.31%, P = 0.037) and 30 (7.37% vs 26.92%, P < 0.001) days after initial endoscopy were significantly lower in the PU than in the DL group after propensity score matching. During the median follow-up period of 52 months (IQR, 34-70 months), there was no difference in overall survival rate (67.9% vs 82.7%, P = 0.518). CONCLUSIONS: Although DL is a rare cause of upper GI bleeding, it requires endoscopic hemostasis more frequently and has a higher rate of rebleeding than PU even after therapeutic endoscopy. Endoscopists should pay attention and perform active endoscopic hemostasis for DL bleeding.

Role of Endoscopy in Motility Disorders of Upper Gastrointestinal Tract.

Gastrointestinal motility disorders have a wide range of symptoms and affect patients' quality of life. With the advancement of endoscopy, the diagnostic and therapeutic roles of endoscopy in motility disorders is becoming more significant. Endoscopy is necessary to rule out possible organic diseases in patients with suspected motility disorders and provide significant clues for their diagnosis. Moreover, interventional endoscopy may be a primary or alternative treatment option for selected patients with motility disorders, and it is becoming a promising field as new therapeutic applications are developed and utilized for various motility disorders. This review may provide suitable indications for the use of endoscopy in diagnosing and treating motility disorders of the upper gastrointestinal tract.

Clinical outcomes of marginal ulcer bleeding compared with those of peptic ulcer bleeding.

BACKGROUND: Marginal ulcer bleeding (MUB) is a complication that can occur following several types of surgery. However, few studies exist on it. Therefore, this study aimed to compare the clinical outcomes of MUB with those of peptic ulcer bleeding (PUB). METHODS: Between January 2013 and December 2017, 5,076 patients underwent emergent esophagogastroduodenoscopy for suspected upper gastrointestinal bleeding. We retrospectively reviewed and analyzed the medical records of MUB and PUB patients and developed a propensity score matching (PSM) method to adjust for between-group differences in baseline characteristics with 1:2 ratios. Sex, age, body mass index (BMI), underlying diseases, and drugs were included as matching factors. RESULTS: A total of 64 and 678 patients were diagnosed with MUB and PUB, respectively, on emergent esophagogastroduodenoscopy, and 62 and 124 patients with MUB and PUB, respectively, were selected after PSM. Rebleeding was significantly higher in patients with MUB than in those with PUB (57.8% vs 9.1%, p < 0.001). Mortality caused by bleeding was higher in patients with MUB than in those with PUB (4.7% vs. 0.4%, p < 0.001). Multivariate analysis revealed that proton pump inhibitor (PPI) administration (odds ratio [OR], 0.14; 95% confidence interval [CI], 0.03-0.56; p = 0.011) after first bleeding was inversely correlated with MUB rebleeding. Large ulcer size (> 1 cm) (OR, 6.69; 95% CI, 1.95-27.94; p = 0.005) and surgery covering pancreas (OR, 3.97; 95% CI, 1.19-15.04) were independent risk factors for MUB rebleeding. CONCLUSIONS: MUB showed a severe clinical course than PUB. Therefore, MUB should be managed more cautiously, especially for large ulcers and pancreatic surgery. Prophylactic PPI administration may be helpful in reducing rebleeding in MUB.

Conventional endoscopic mucosal resection versus modified endoscopic mucosal resection for duodenal neuroendocrine tumor.

BACKGROUND AND AIMS: As the incidence of duodenal neuroendocrine tumors (DNET) is steadily increasing, the role of endoscopic treatment for appropriate lesions is becoming more significant. We aimed to compare the outcomes according to lesion size and endoscopic mucosal resection (EMR) techniques for DNET treatment. PATIENTS AND METHODS: Patients who underwent endoscopic treatment for DNET between June 2000 and December 2019 were included. The clinicopathologic features and treatment outcomes were investigated by reviewing medical records. RESULTS: Overall, 104 cases underwent endoscopic resection for nonampullary DNET, including conventional EMR (n = 57), cap-assisted EMR (EMR-C, n = 19), and precut EMR (EMR-P, n = 28). The en bloc resection rates (100% vs. 94.7% vs. 96.4%) and histologic complete resection rates (45.6% vs. 52.6% vs. 57.1%) were not significantly different between the EMR, EMR-C, and EMR-P groups. The histologic complete resection rates were significantly higher in lesions < 10 mm than in lesions ≥ 10 mm (69.8% vs. 38.9%, P = 0.013). In lesions < 10 mm, perforation occurred more frequently in the modified EMR group than in the conventional EMR group (13.2% vs. 0.0%, P = 0.007). During the median follow-up period of 88.0 months, the recurrence-free survival (92.2% vs. 94.4% vs. 92.1%) and overall survival (98.0% vs. 88.1% vs. 100.0%) rates did not show significant differences between the EMR, EMR-C, and EMR-P groups. CONCLUSION: Conventional EMR and modified EMR are feasible and effective for the treatment of nonampullary DNET sized < 10 mm and limited to mucosal and submucosal layer. Additionally, endoscopists should be aware of the high risk of perforation in modified EMR.

Clinical Significance of Epstein-Barr Virus and Helicobacter pylori Infection in Gastric Carcinoma.

Background/Aims: Epstein-Barr virus (EBV) and Helicobacter pylori (HP) coinfection may synergistically induce severe inflammatory responses in the stomach tissue, increasing the risk of developing gastric cancer. We aimed to analyze the effect of EBV and HP coinfection on the clinicopathologic features and prognosis of gastric cancer, as well as to evaluate the role of EBV infection in non-gastric carcinoma with lymphoid stroma (non-GCLS). Methods: Overall, 956 patients who underwent surgery for gastric cancer between September 2014 and August 2015 were eligible and divided into groups, according to GCLS morphology, EBV infection, and HP infection. Clinicopathologic characteristics and oncologic outcomes were analyzed retrospectively. Results: EBV and HP coinfection was significantly associated with male sex, proximal location, GCLS morphology, and equivocal p53 expression (p<0.001). Multivariate analysis revealed that EBV infection alone (hazard ratio [HR], 0.362; 95% CI, 0.131 to 0.996; p=0.049) and lower third location (HR, 0.624; 95% CI, 0.413 to 0.943; p=0.025) were inversely correlated with overall survival. During median follow-up period of 72 months, overall survival rate was not significantly different between the EBV and HP coinfection group and others (97.6% vs 86.8%; log-rank p=0.144). In non-GCLS patients (n=920), overall survival rate was not significantly different between the EBV infection group and others (96.9% vs 86.4%; log-rank p=0.126). Conclusions: EBV and HP coinfection is not an independent prognostic factor for gastric cancer. EBV infection status, regardless of HP infection, affects the clinicopathologic features of all types of gastric cancer. However, it does not lead to a significant difference in overall survival of non-GCLS patients.

Real-Time Polymerase Chain Reaction for the Detection of Helicobacter pylori and Clarithromycin Resistance.

Background/Aims: Real-time polymerase chain reaction (RT-PCR) is a fast and simple method for the simultaneous detection of clarithromycin (CLR) resistance and Helicobacter pylori. We evaluated the effectiveness of RT-PCR compared to that of the rapid urease test (RUT) and assessed its value in verifying CLR resistance. Methods: A total of 70 specimens with confirmed H. pylori infection in culture were enrolled and analyzed in this prospective study. All specimens were subjected to RT-PCR assay using fluorescence melting peak signals to detect H. pylori infection and CLR resistances caused by either A2142G or A2143G mutations in the 23S ribosomal RNA gene (23S rRNA). The results were compared to those of RUT and antimicrobial susceptibility culturing tests to investigate the efficacy of RT-PCR. Results: Among the 70 specimens analyzed, the positivity rate was 97.1% (68/70) with RT-PCR and 82.9% (58/70) with RUT. CLR resistance (minimum inhibitory concentration >1.0 µg/mL) was confirmed in 18.6% (13/70), and fluorescence melting curve analysis showed that 84.6% (11/13) had point mutations in 23S rRNA. Ten specimens had only A2143G mutation, and one specimen contained both A2142G and A2143G mutations. Conclusions: RT-PCR assay was found to be more efficient than RUT in detecting H. pylori infection and could effectively verify CLR resistance compared to the antimicrobial susceptibility culturing test. Considering the high sensitivity and accessibility of RT-PCR method, it could be used to easily detect CLR-resistant H. pylori, thus helping clinicians select suitable treatment regimen and improve the eradication rate.

Usefulness of EndoFLIP in Diverticular Peroral Endoscopic Myotomy for Symptomatic Epiphrenic Diverticulum.

Background/Aims: Diverticular peroral endoscopic myotomy (D-POEM) is known to be a safe and feasible technique for managing diverticular diseases of the esophagus. In this study, we aim to report our experience with D-POEM and to investigate the usefulness of endoscopic functional luminal imaging probe (EndoFLIP) in determining the need for cardiomyotomy with septotomy for symptomatic epiphrenic diverticulum. Methods: Consecutive patients who underwent D-POEM for symptomatic epiphrenic diverticulum between September 2019 and September 2021 were eligible for this study. EndoFLIP and high-resolution manometry results and endoscopic treatment outcomes were retrospectively investigated. Results: A total of 9 patients with symptomatic epiphrenic diverticulum were included. The median size of the diverticulum and septum was 50 (interquartile range [IQR], 48-80) mm and 20 (IQR, 20-30) mm, respectively. The overall technical success rate was 100%, with a median procedure time of 60 (IQR, 46-100) minutes. The 5 patients (high-resolution manometry results; 3 normal, 1 ineffective esophageal motility, and 1 Jackhammer esophagus) who had decreased esophagogastric junction distensibility index on pre-procedure EndoFLIP underwent cardiomyotomy with septotomy regardless of the presence of esophageal motility disorders, and the distensibility index increased and normalized after procedure. The mean dysphagia score decreased from 2.0 ± 1.0 pre-procedure to 0.4 ± 0.7 during a median follow-up of 11 (IQR, 4-21) months post-procedure. No serious adverse events that required surgical intervention or delayed discharge were noted. Conclusions: EndoFLIP may help decide whether to perform combined cardiomyotomy and septotomy for the treatment of an epiphrenic diverticulum. Further large-scale studies are needed to confirm these results.

Clinical Outcomes of Patients with Benign Peptic Ulcer Bleeding After an Emergency Endoscopy Based on Patient Location.

BACKGROUND AND AIMS: In the efforts toward reducing bleeding-related mortality, it is crucial to determine the risk factors for rebleeding after endoscopic hemostasis in benign peptic ulcer (BPU). METHODS: Between 2013 and 2017, the medical records of 864 BPU patients were selected from 5076 who had undergone emergency endoscopy for suspected upper gastrointestinal bleeding. Patients who visited the emergency room or were hospitalized for other illnesses were selected. The primary end point was rebleeding within 30 days after initial endoscopy. The risk factors of rebleeding and subgroup analyses according to patient location were evaluated. RESULTS: Among 864 BPU bleeding patients, rebleeding after completion of BPU bleeding occurred in 140 (16.2%). Initial indicators of hypotension (OR 1.878, p = 0.005) and Forrest classes Ia (OR 25.53, p < 0.001), Ib (OR 27.91, p = 0.005), IIa (OR 21.41, p < 0.001), and IIb (OR 23.74, p < 0.001) were independent risk factors of rebleeding compared to Forrest class III, and being inpatients (OR 1.75, p = 0.01). Compared to the outpatients, the inpatients showed significantly higher rebleeding rates (25.6% vs 13.8%, p < 0.001), predictive bleeding scores, red blood transfusion counts, proportion of Forrest classes Ia, Ib, and IIb (p < 0.001), and overall mortality rates (68.8% vs 34.0%, p < 0.001). CONCLUSIONS: Patient location was a novel predictive factor of BPU rebleeding. Particularly, being an inpatient correlated with increased rebleeding. Furthermore, Forrest classes Ia, Ib, IIa, and IIb were predictive of rebleeding not only the included BPUs, but also in the inpatient or outpatient groups.

Scoring systems for predicting clinical outcomes in peptic ulcer bleeding.

Few studies have focused on assessing the usefulness of scoring systems such as the Rockall score (RS), Glasgow-Blatchford score (GBS), and AIMS65 score for risk stratification and prognosis prediction in peptic ulcer bleeding patients. This study aimed to assess scoring systems in predicting clinical outcomes of patients with peptic ulcer bleeding. A total of 682 peptic ulcer bleeding patients who underwent esophagogastroduodenoscopy between January 2013 and December 2017 were found eligible for this study. The area under the receiver-operating characteristic curve (AUROC) of each score was calculated for predicting rebleeding, hospitalization, blood transfusion, and mortality. The median age of patients was 64 (interquartile range, 56-75) years. Of the patients, 74.9% were men, and 373 underwent endoscopic intervention. The median RS, GBS, and AIMS65 scores were significantly higher in patients who underwent endoscopic intervention than in those who did not. The AUROC of RS for predicting rebleeding was significantly higher than that of GBS (P = .022) or AIMS65 (P < .001). GBS best predicted the need for blood transfusion than either pre-RS (P = .013) or AIMS65 (P = .001). AIMS65 score showed the highest AUROC for mortality (0.652 vs. 0.622 vs. 0.691). RS was significantly associated with rebleeding (odds ratio, 1.430; P < .001) and overall survival (hazard ratio, 1.217; P < .001). The RS, GBS, and AIMS65 scoring systems are acceptable tools for predicting clinical outcomes in peptic ulcer bleeding. RS is an independent prognostic factor of rebleeding and overall survival.

Objective Interpretation of the Rapid Urease Test for Helicobacter pylori Infection Using Colorimetry.

BACKGROUND: The rapid urease test (RUT) is a major diagnostic tool for detecting Helicobacter pylori infection. This study aimed to establish an objective method for measuring the color changes in the RUT kit to improve the test's diagnostic accuracy. METHODS: A UV-visible spectrophotometer was selected as the colorimeter; experiments were conducted in three stages to objectively identify the color changes in the RUT kit. RESULTS: First, the urea broth solution showed an identifiable color change from yellow to red as the pH increased by 0.2. The largest transmittance difference detected using the UV-visible spectrophotometer was observed at a 590-nm wavelength. Second, the commercialized RUT kit also showed a gradual color change according to the pH change detected using the UV-visible spectrophotometer. Third, 13 cases of negative RUT results with a biopsy specimen and 16 of positive RUT results were collected. The transmittance detected using the UV-visible spectrophotometer showed a clear division between the positive and negative RUT groups; the largest difference was observed at a 559-nm wavelength. The lowest transmittance in the negative RUT group was 64, while the highest in the positive RUT group was 56, at the 559-nm wavelength. The UV-visible spectrophotometry reading showed a consistency of 92.7% compared with that of manual reading. CONCLUSION: A transmittance of 60 at a 559-nm wavelength detected using UV-visible spectrophotometer can be used as a cutoff value for interpreting RUT results; this will help develop an automatic RUT kit reader with a high accuracy.

Outcomes of endoscopic submucosal dissection for superficial esophageal neoplasms in patients with liver cirrhosis.

BACKGROUND/AIMS: The treatment of superficial esophageal neoplasms (SENs) in cirrhotic patients is challenging and rarely investigated. We evaluated the outcomes of endoscopic submucosal dissection (ESD) to determine the efficacy and safety of treating SENs in patients with liver cirrhosis. METHODS: The baseline characteristics and treatment outcomes of patients who underwent ESD for SENs between November 2005 and December 2017 were retrospectively reviewed. RESULTS: ESD was performed in 437 patients with 481 SENs, including 15 cirrhotic patients with 17 SENs. En bloc resection (88.2% vs. 97.0%) and curative resection (64.7% vs. 78.9%) rates were not different between the cirrhosis and non-cirrhosis groups (p=0.105 and p=0.224, respectively). Bleeding was more common in cirrhotic patients (p=0.054), and all cases were successfully controlled endoscopically. The median procedure and hospitalization duration did not differ between the groups. Overall survival was lower in cirrhotic patients (p=0.003), while disease-specific survival did not differ between the groups (p=0.85). CONCLUSION: ESD could be a safe and effective treatment option for SENs in patients with cirrhosis. Detailed preprocedural assessments are needed, including determination of liver function, esophageal varix status, and remaining life expectancy, to identify patients who will obtain the greatest benefit.