Impact of Helicobacter pylori infection on fluid duodenal microbial community structure and microbial metabolic pathways.

BACKGROUND: The bioactivities of commensal duodenal microbiota greatly influence the biofunction of hosts. We investigated the role of Helicobacter pylori infection in extra-gastroduodenal diseases by determining the impact of H. pylori infection on the duodenal microbiota. We sequenced 16 S rRNA genes in samples aspirated from the descending duodenum of 47 (male, 20; female, 27) individuals who were screened for gastric cancer. Samples were analysed using 16 S rRNA gene amplicon sequencing, and the LEFSe and Kyoto Encyclopaedia of Genes and Genomes methods were used to determine whether the duodenal microflora and microbial biofunctions were affected using H. pylori infection. RESULTS: Thirteen and 34 participants tested positive and negative for H. pylori, respectively. We identified 1,404 bacterial operational taxonomic units from 23 phyla and 253 genera. H. pylori infection changed the relative mean abundance of three phyla (Proteobacteria, Actinobacteria, and TM7) and ten genera (Neisseria, Rothia, TM7-3, Leptotrichia, Lachnospiraceae, Megasphaera, F16, Moryella, Filifactor, and Paludibacter). Microbiota features were significantly influenced in H. pylori-positive participants by 12 taxa mostly classified as Gammaproteobacteria. Microbial functional annotation revealed that H. pylori significantly affected 12 microbial metabolic pathways. CONCLUSIONS: H. pylori disrupted normal bacterial communities in the duodenum and changed the biofunctions of commensal microbiota primarily by upregulating specific metabolic pathways. Such upregulation may be involved in the onset of diseases associated with H. pylori infection.

Clinical prediction of complicated appendicitis: A case-control study utilizing logistic regression.

BACKGROUND: Since high-quality evidence on conservative treatment of acute appendicitis using antibiotics has increased, differentiation of patients with complicated appendicitis (CA) from those with simple appendicitis (SA) has become increasingly important. Previous studies have revealed that male gender, advanced age, comorbid conditions, prehospital delay, fever, and anorexia are risk factors of perforated appendicitis. Elevated serum C-reactive protein (CRP) level and hyponatremia have also been reported as predictive biomarkers of CA. However, confounding between various factors is problematic because most previous studies were limited to univariate analysis. AIM: To evaluate non-laboratory and laboratory predictive factors of CA using logistic regression analyses. METHODS: We performed an exploratory, single-center, retrospective case-control study that evaluated 198 patients (83.9%) with SA and 38 patients (16.1%) with CA. Diagnoses were confirmed by computed tomography images for all cases. We compared age, sex, onset-to-visit interval, epigastric/periumbilical pain, right lower quadrant pain, nausea/vomiting, diarrhea, anorexia, medical history (of previous non-surgically treated appendicitis, diabetes, hypertension, dyslipidemia, liver cirrhosis, hemodialysis, chronic lung diseases, malignant tumors, immunosuppressant use, and antiplatelet use), vital signs, physical findings, and laboratory data to select the explanatory variates for logistic regression. Based on the univariate comparisons, we performed logistic regression for clinical differentiation between CA and SA using only non-laboratory factors and also including both non-laboratory and laboratory factors. RESULTS: The 236 eligible patients consisted of 198 patients (83.9%) with SA and 38 patients (16.1%) with CA. The median ages were 34 years old [interquartile ranges (IR), 24-45 years] in the SA group and 49 years old (IR, 35-63 years) in the CA group (P < 0.001). The median onset-to-visit interval was 1 d (IR, 0-1) and 1 d (IR, 1-2) in the SA and CA groups, respectively (P < 0.001). Heart rate, body temperature, and serum CRP level in the CA group were significantly higher than in the SA group; glomerular filtration rate and serum sodium were significantly lower in the CA group. Anorexia was significantly more prevalent in the CA group. The regression model including age, onset-to-visit interval, anorexia, tachycardia, and fever as non-laboratory predictive factors of CA (Model 1) showed that age ≥ 65 years old, longer onset-to-visit interval, and anorexia had significantly high odds ratios. The logistic regression for prediction of CA including age, onset-to-visit interval, anorexia, serum CRP level, hyponatremia (serum sodium < 135 mEq/L), and glomerular filtration rate < 60 mL/min/1.73 m2 (Model 2) showed that only elevated CRP levels had significantly high odds ratios. Under the curve values of receiver operating characteristics curves of each regression model were 0.74 for Model 1 and 0.87 for Model 2. CONCLUSION: Our logistic regression analysis on differentiating factors of CA from SA showed that high CRP level was a strong dose-dependent predictor of CA.

Effect of acotiamide on gastric emptying in healthy adult humans.

BACKGROUND: Acotiamide is a first-in-class drug that is used to treat functional dyspepsia (FD). It is considered that acotiamide acts as an antagonist on muscarinic autoreceptors in the enteric nervous system and inhibits acetylcholinesterase activity. We examined the effect of acotiamide on gastric emptying in healthy adult humans. MATERIALS AND METHODS: Twelve healthy adult males were enrolled in this double-blind crossover study. Acotiamide or placebo was administered orally in the 12 subjects 30 min before ingestion of a nutritional liquid meal (400 Kcal/400 mL). Six of the 12 participants took 100 mg of acotiamide or placebo, and six of the 12 participants took 300 mg of acotiamide or placebo in a double-blind crossover fashion. All subjects underwent measurement of gastric emptying by the (13) C breath test. RESULTS: After the meal with placebo was ingested, the %dose/h curve ascended. The %dose/h curve after a meal with 100 or 300 mg of acotiamide ascended in an identical manner compared with the results with placebo. No significant differences were observed at any studied time point, and there were no significant changes in gastric emptying parameters (gastric emptying coefficient, t-1/2ex and t-lag ex). CONCLUSIONS: A single administration of 100 or 300 mg of acotiamide did not affect gastric emptying after a liquid meal in healthy adult humans. Acotiamide has profound effects on restoring delayed gastric emptying and impaired accommodation in patients with FD but may have no effect on gastric emptying in healthy subjects. Such pharmacological actions have not been observed in previous gastroprokinetic studies.

Gastric schwannomas show an obviously increased fluorodeoxyglucose uptake in positron emission tomography: report of two cases.

Schwannomas are tumors originating from any nerve that has a Schwann cell sheath. Gastrointestinal (GI) schwannomas represent only 3% of all GI mesenchymal tumors. The stomach is the most common site of GI schwannomas, and schwannomas account for 0.2% of all gastric neoplasms. This report presents two cases of gastric schwannomas showing increased [18F]fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET; maximum standardized uptake value 7.10 and 6.05). Additional immunohistochemical staining of glucose transporter type 1 (GLUT1) and the autocrine motility factor (AMF) was conducted after the tumors were resected, to identify the mechanism that increased FDG uptake on PET. Immunohistochemical expression of AMF was positive in both cases, whereas GLUT1 was negative. Autocrine motility factor is also known as phosphoglucose isomerase. However, the mechanism by which FDG is accumulated in schwannoma cells is uncertain, and may be related to intracellular glycolytic activity.

Proton pump inhibitors improve acid-related dyspepsia in gastroesophageal reflux disease patients.

It has been reported that proton pump inhibitors are more effective than H2 receptor antagonists in patients with functional dyspepsia. Dyspeptic symptoms that respond to proton pump inhibitors are classified as acid-related dyspepsia. A new questionnaire for assessing gastroesophageal reflux disease (GERD), the Frequency Scale for Symptoms of GERD, covers the 12 most common symptoms of GERD patients. A quantitative assessment of the changes of reflux symptoms and acid-related dyspepsia was made in GERD patients receiving proton pump inhibitor therapy. Sixty-eight GERD patients receiving proton pump inhibitor therapy completed the questionnaire before and after treatment for 8 weeks. There is a significant positive correlation between reflux symptoms and acid-related dyspepsia before and after therapy (r = 0.569 and r = 0.569; both P's < 0.001) and acid-related dyspepsia in patients with both nonerosive and erosive GERD. We conclude that GERD patients suffer not only from reflux symptoms, but also from acid-related dyspepsia, and proton pump inhibitors improve both types of symptoms.

Diagnosis of gastroesophageal reflux disease using a new questionnaire.

BACKGROUND AND AIM: An early and accurate evaluation by a general practitioner is needed to screen out non-gastroesophageal reflux disease (GERD) patients. A recent questionnaire (QUEST) highlighted problems with specificity and complexity, so the aim of the present study was to design a simplified questionnaire. METHODS: When admitted to hospital to undergo an upper gastrointestinal endoscopy for suspected GERD, 333 patients completed a 50-item questionnaire requiring 'yes/no' answers to different combinations of questions relating to symptoms of upper gastrointestinal tract conditions (e.g. GERD, ulcers and functional dyspepsia) and psychosomatic symptoms. The endoscopic diagnosis was then correlated with the rate of positive answers to each question. RESULTS: Based on the analysis of the 50 items, the 8-10 questions most often answered affirmatively by each of the GERD and non-GERD groups were chosen for the simplified questionnaire. Three draft questionnaires were compiled. After calculating the sensitivity, specificity and accuracy in relation to the diagnosis of GERD and other conditions, it was found that questionnaire B (selection of persons answering 'yes' to at least one of questions 1-5 and exclusion of persons answering 'yes' to at least three of questions 7-10) had a high sensitivity, high specificity and low false positive rate. CONCLUSION: A novel questionnaire was developed. It was designed to detect the symptoms of GERD while simultaneously excluding non-GERD patients. This simplified nine-item simplified questionnaire had a sensitivity of 79.8%, a specificity of 53.6% and an accuracy of 63.4%.

Development and evaluation of FSSG: frequency scale for the symptoms of GERD.

BACKGROUND: The aim of this study was to produce a simplified questionnaire for evaluation of the symptoms of gastroesophageal reflux disease (GERD). METHODS: A total of 124 patients with an endoscopic diagnosis of GERD completed a 50-part questionnaire, requiring only "yes" or "no" answers, that covered various symptoms related to the upper gastrointestinal tract, as well as psychosomatic symptoms. The 12 questions to which patients most often answered "yes" were selected, and were assigned scores (never = 0; occasionally = 1; sometimes = 2; often = 3; and always = 4) to produce a frequency scale for symptoms of GERD (FSSG). Sensitivity, specificity, and accuracy of the FSSG questionnaire were evaluated in another group of patients with GERD and non-GERD. The usefulness of this questionnaire was evaluated in 26 other GERD patients who were treated with proton pump inhibitors for 8 weeks. RESULTS: When the cutoff score was set at 8 points, the FSSG showed a sensitivity of 62%, a specificity of 59%, and an accuracy of 60%, whereas a cutoff score of 10 points altered these values to 55%, 69%, and 63%. The score obtained using the questionnaire correlated well with the extent of endoscopic improvement in patients with mild or severe GERD. CONCLUSIONS: This new questionnaire is useful for the objective evaluation of symptoms in GERD patients.

A case for gastrointestinal stromal tumor (GIST) with reference to its ultrastructure and 'gain-of-function' mutation.

A case for primary gastrointestinal stromal tumor (GIST) is described with reference to its ultrastructural characteristics and mutation within the exon 11 of c-kit gene. A forty-seven years old woman complaining of dysphasia was examined by endoscopy, which depicted a submucosal tumor (70 mm in diameter) with ulcerations at the fundus of the stomach. Histopathologically, the tumor cells had large nuclei and eosinophilic cytoplasm and were frequently during mitosis phase. The tumor cells were immunopositive for KIT, CD 34 and vimentin, suggesting their fibroblast-like characteristics. In contrast, desmin and S-100, a smooth muscle and an enteroglial marker, were not immunopositive within the cells. At least 30 % of the tumor cells possessed MIB-I and 20 % of them possessed p53, which are compatible with fast development of the tumor. By electron microscopy, the tumor cells possessed large oval nuclei, abundant mitochondria, caveolae and smooth endoplasmic reticulums, while no gap junctions were seen on the cells: The tumor cells thus possessed interstitial cells-like characteristics at least in part. DNA mutation search for the tumor cells however realized no gain-of-function mutation within the exon 11 of the c-kit gene, suggesting existence of other mechanism for neoplasmic growth of the tumor cells classified as gastrointestinal stromal tumors.