Proton-pumping rhodopsin (PPR) is a simple photosystem widely distributed in nature. By binding to retinal, PPR can transfer protons from the cytoplasmic to the extracellular side of the membrane under illumination, creating a proton motive force (PMF) to synthesize ATP. The conversion of light into chemical energy by introducing rhodopsin into nonphotosynthetic engineered strains could contribute to promoting growth, increasing production and improving cell tolerance of microbial hosts. Gloeorhodopsin (GR) is a PPR from Gloeobacter violaceus PCC 7421. We expressed GR heterologously in Escherichia coli and verified its functional activity. GR could properly function as a light-driven proton pump and its absorption maximum was at 539 nm. We observed that GR was mainly located on the cell membrane and no inclusion body could be found. After increasing expression level by ribosome binding site optimization, intracellular ATP increased, suggesting that GR could supply additional energy to heterologous hosts under given conditions.
Cyanobacteria/metabolism* ; Escherichia coli/metabolism* ; Proton Pumps ; Rhodopsin/metabolism* ; Rhodopsins, Microbial/metabolism*

12 weeks) were 81.8%, 50.0%, and 55.1% for DFD, and 68.8%, 50.0%, and 40.0% for SFED. Response based on age ( < 6, 6–12, and >12 years) were 59.3%, 42.9%, and 67.5% for DFD, and 36.4%, 58.8%, and 72.7% for SFED. In patients treated with DFD, concomitant proton pump inhibitor (PPI) administration resulted in improved outcomes (p=0.0177). Bivariate regression analysis showed that PPI with diet is the only predictor of response (p=0.0491), however, there were no significant predictors on multiple regression analysis.CONCLUSION: DFD and SFED are effective first line therapies for EoE. DFD should be tried first before extensive elimination diets. Concomitant therapy with PPI's may be helpful.]]>
Child ; Connecticut ; Diet ; Endoscopy ; Eosinophilic Esophagitis ; Eosinophils ; Humans ; Male ; Proton Pump Inhibitors ; Proton Pumps ; Retrospective Studies

proton pump inhibitor (PPI)-based standard triple therapy (STT; PPI-clarithromycin-amoxicillin). Bismuth-containing quadruple therapy was used as second-line therapy. Eradication success was defined as a negative ¹³C-urea breath test.RESULTS: In first-line treatment, eradication rate was 78.5% (106/135) and 78.6% (114/143) in the 7-day and 14-day treatment in per-protocol (PP) analysis (P = 0.805). In intention-to-treat (ITT) analysis, eradication rate was 64.0% (114/178) and 66.0% (126/191), respectively (P = 0.924). There was no significant difference in drug compliance (81.5% vs. 84.3%, P = 0.320). In second-line therapy, eradication rate was not significantly different in both treatments of PP analysis (91.7% [33/36] vs. 100% [45/45], P = 0.084). In the ITT analysis, eradication rate was 79.6% (35/44) and 90.4% (47/52), respectively (P = 0.080). Drug compliances were not significantly different between the two groups (95.5% vs. 98.1%, P = 0.728).CONCLUSION: PPI-based STT for H. pylori is not efficient as a first-line therapy both in 7 days and 14 days in Korea. Although bismuth-containing quadruple therapy for 14 days as a second line therapy tend to show higher eradication rate compared to 7-day therapy, this should be elucidated by further larger scaled studies.TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02487511]]>
Anti-Bacterial Agents ; Breath Tests ; Compliance ; Drug Resistance ; Helicobacter pylori ; Helicobacter ; Humans ; Korea ; Proton Pump Inhibitors ; Proton Pumps ; Stomach Neoplasms ; Treatment Outcome

BACKGROUND/AIMS: The Gastroesophageal Reflux Disease Questionnaire (GerdQ) has been developed and validated as a tool for the diagnosis of gastroesophageal reflux disease (GERD) in patients with gastrointestinal symptoms. However, the GerdQ and the cutoff value for determining GERD has not been validated in Korea. METHODS: Patients with symptoms suggestive of GERD were consecutively recruited. The Korean version of GerdQ was developed through a forward-backward translation process according to the cross-cultural adaptation method. Endoscopically documented esophagitis, abnormal results on 24-hour ambulatory pH recording with symptom association monitoring, or response to proton pump inhibitor treatment were used as diagnostic references for GERD. The reproducibility and test characteristics of the Korean version of GerdQ were assessed. RESULTS: A total of 149 patients with a median age of 55 years were analyzed. The intra-class correlation coefficient of 2 subsequently measured GerdQ scores was 0.651 (95% CI, 0.518–0.748). The cutoff value of 8 was found to have the highest sensitivity (64.9%; 95% CI, 56.2–73.7) and specificity (71.4%; 95% CI, 56.5–86.4) for the diagnosis of GERD. The questionnaire had a high positive predictive value (88.1%; 95% CI, 81.2–95.0), but a low negative predictive value (38.5%; 95% CI, 26.2–50.3) for GERD. Any symptom improvement on proton pump inhibitor treatment showed a sensitivity of 93.0% (95% CI, 88.3–97.7) and a specificity of 48.6% (95% CI, 32.0–65.1) for GERD. CONCLUSION: The Korean version of GerdQ is a useful complementary tool in the diagnosis of GERD.
Diagnosis ; Esophagitis ; Gastroesophageal Reflux ; Humans ; Hydrogen-Ion Concentration ; Korea ; Methods ; Proton Pumps ; Sensitivity and Specificity ; Surveys and Questionnaires ; Symptom Assessment

OBJECTIVE: To characterize the endoscopic features of upper gastrointestinal tract in patients with systemic sclerosis (SSc) compared with those in the healthy controls. METHODS: Data on esophagogastroduodenoscopy (EGD) in 180 patients with SSc (SSc group) were compared with that from the 181 age- and sex-matched healthy control who underwent EGD for routine check-up (control group). Clinical data of participants at the time of EGD (defined as baseline) were collected from electric medical record. Endoscopic findings were evaluated by two experts with blinded to their clinical features. Primary outcome of the study was prevalence of each endoscopic lesion between the two groups. RESULTS: The mean±standard deviation age and disease duration in the SSc group at baseline were 55.3±11.8 and 2.9±3.7 years, respectively. Compared to the control group, SSc group more frequently showed reflux esophagitis (32.8% vs. 9.4%, p < 0.001). In contrast, prevalence of atrophic gastritis was significantly lower in the SSc group (8.3% vs. 29.3%, p < 0.001). This result was consistent in the multivariable analysis where patients' age and concomitant proton pump inhibitor use were adjusted. There was no case of gastric antral vascular ectasia (GAVE) in both groups. However, 29 (16.1%) patients in SSc group showed a clinically significant anemia (hemoglobin < 10 mg/dL), with none of the endoscopic features showed significant associations with the outcome. CONCLUSION: Patients with SSc showed significantly lower prevalence of atrophic gastritis. There was no case of GAVE, which suggests that clinical phenotype of the SSc could be different according to the ethnicity or geographic region.
Anemia ; Endoscopy ; Endoscopy, Digestive System ; Esophagitis, Peptic ; Gastric Antral Vascular Ectasia ; Gastritis ; Gastritis, Atrophic ; Humans ; Medical Records ; Phenotype ; Prevalence ; Proton Pumps ; Scleroderma, Systemic* ; Upper Gastrointestinal Tract*

Eosinophilic esophagitis is a rare disease in Asian countries, but its incidence is growing rapidly in Western countries. The main pathophysiology of eosinophilic esophagitis is esophageal epithelial barrier dysfunction; disruption of the esophageal epithelial barrier easily induces antigen sensitization to foods and aeroallergens, which leads to subsequent esophageal inflammation as a result of eosinophil recruitment. Here we report a case of an 11-year-old Korean boy who suffered from fever, odynophagia, dysphagia, and chest pain. His upper endoscopic findings showed longitudinal ulcers with a volcano-like appearance at the distal esophagus. Polymerase chain reaction test results and biopsy specimens were positive for herpes simplex virus type 1. He was treated with acyclovir and a proton pump inhibitor, but his follow-up endoscopy showed typical patterns of eosinophilic esophagitis, and the biopsy specimens were compatible with the diagnostic criteria for eosinophilic esophagitis. Therefore, we report a very rare case of eosinophilic esophagitis after herpes esophagitis in a Korean child with normal immunity.
Acyclovir ; Asian Continental Ancestry Group ; Biopsy ; Chest Pain ; Child ; Deglutition Disorders ; Endoscopy ; Eosinophilic Esophagitis ; Eosinophils ; Esophagitis ; Esophagus ; Fever ; Follow-Up Studies ; Herpesvirus 1, Human ; Humans ; Incidence ; Inflammation ; Male ; Polymerase Chain Reaction ; Proton Pumps ; Rare Diseases ; Simplexvirus ; Ulcer

BACKGROUND/AIMS: The aim of this study was to determine the risk factors of multiple gastric polyps according to the histological classification of gastric polyps.METHODS: Subjects with multiple gastric polyps (at least three) during endoscopy were enrolled prospectively. They were assigned to a fundic gland polyp (FGP) group and hyperplastic polyp (HP) group based on a histological classification of gastric polyps. Helicobacter pylori (H. pylori) was confirmed by its histology. Serum gastrin was measured using the radioimmunoassay method. A questionnaire was taken regarding the intake of proton pump inhibitor and nonsteroidal anti-inflammatory drugs, alcohol, smoking history, and diet.RESULTS: Among the 60 subjects enrolled from 2015 to 2018 at Seoul National University Bungdang Hospital, 47 and 13 subjects were assigned to the FGP and HP groups, respectively. The H. pylori infection rate was 12.8% in the FGP group, which is lower than that in the HP group (69.2%, p<0.001). The gastrin level was higher in the HP group (194.7 pg/dL, range 50.6–387.8 pg/dL) than in the FGP group (57.4 pg/dL, range 24.8–79.0 pg/dL) (p=0.007). Histologically, neutrophil infiltration in the antrum and body of the stomach were higher in the HP group than in the FGP group (p=0.022 and p=0.030, respectively). In contrast, monocyte infiltration in the antrum and body of the stomach were higher in the FGP group than in the HP group (p=0.018 and p<0.001, respectively).CONCLUSIONS: HPs arise from inflammation caused by H. pylori. On the other hand, the FGP was not associated with H. pylori or environmental factors.
Classification ; Cohort Studies ; Diet ; Endoscopy ; Gastrins ; Hand ; Helicobacter pylori ; Inflammation ; Methods ; Monocytes ; Neutrophil Infiltration ; Polyps ; Prospective Studies ; Proton Pump Inhibitors ; Proton Pumps ; Radioimmunoassay ; Risk Factors ; Seoul ; Smoke ; Smoking ; Stomach

No abstract available.
Critical Care ; Intensive Care Units ; Proton Pumps ; Protons ; Ulcer

Gastroesophageal reflux disease (GERD) is diagnosed according to the medical history or in response to proton pump inhibitor therapy. However, the need for further testing is always appropriate. The decisive evidence for the current diagnosis of GERD is severe erosive esophagitis of Los Angeles grade C or D, long-segment Barrett's mucosa or peptic strictures seen on endoscopy or an acid exposure time >6% on ambulatory pH or pH impedance monitoring. If ambulatory reflux monitoring correlates between reflux and the symptoms, then the diagnosis and treatment are certain. If it is difficult to clearly diagnose this malady as seen upon endoscopy and ph/pH impedance monitoring, then this review recommends the biopsy findings, motor evaluation and novel impedance metrics. Novel impedance metrics include the baseline impedance and the post reflux swallow-induced peristaltic wave index. Therefore, making a future GERD diagnosis should focus on defining the patient's phenotype. The phenotype is determined by the level of reflux exposure, clearance efficacy, anatomy of the esophageal gastric junction, and the psychological state of the patient. The purpose of this review is to clarify the diagnostic guideline for GERD according to several test methods.
Biopsy ; Consensus ; Constriction, Pathologic ; Diagnosis ; Electric Impedance ; Endoscopy ; Esophageal pH Monitoring ; Esophagitis ; Gastroesophageal Reflux ; Humans ; Hydrogen-Ion Concentration ; Manometry ; Mucous Membrane ; Phenotype ; Proton Pumps

BACKGROUND/AIMS: The association between Helicobacter pylori infection and nonsteroidal anti-inflammatory drugs (NSAIDs) or low-dose aspirin therapy as a risk factor for peptic ulcer bleeding (PUB) remains unclear. This study investigated the risk of PUB associated with H. pylori infection and NSAID or low-dose aspirin therapy in patients with PUD. MATERIALS AND METHODS: This case-control study investigated 340 patients with PUB between 2012 and 2016. The control group comprised age and sex-matched patients with endoscopically documented non-bleeding ulcers. Using logistic regression analysis, the adjusted odds ratio (AOR) was calculated for the risk of PUB. RESULTS: Of the patients investigated, 57.9% in the study group and 51.8% in the control group were diagnosed with H. pylori infection (P=0.106). Logistic regression analysis showed synergistic interaction between H. pylori infection and low-dose aspirin therapy. Multivariate analysis showed that low-dose aspirin (AOR 3.92, P < 0.001), NSAIDs (AOR 2.98, P=0.001), warfarin (AOR 14.57, P=0.011), gastric ulcer (compared with duodenal ulcer) (AOR 1.65, P=0.01), and smoking (AOR 1.97, P=0.004) increased the risk of PUB compared with the risk of PUD. CONCLUSIONS: Both NSAIDs and aspirin are independent risk factors for bleeding in patients with PUD. Additionally, low-dose aspirin therapy concomitant with H. pylori infection produced a synergistic effect. Therefore, H. pylori eradication may be crucial in aspirin users. Moreover, a proton pump inhibitor should be prescribed in patients with a history of bleeding ulcers who need long-term NSAID treatment.
Anti-Inflammatory Agents, Non-Steroidal ; Aspirin ; Case-Control Studies ; Helicobacter pylori ; Helicobacter ; Hemorrhage ; Humans ; Logistic Models ; Multivariate Analysis ; Odds Ratio ; Peptic Ulcer ; Proton Pumps ; Risk Factors ; Smoke ; Smoking ; Stomach Ulcer ; Ulcer ; Warfarin