Effects of aspirin on the development of Helicobacter pylori-induced gastric inflammation and heterotopic proliferative glands in Mongolian gerbils

BACKGROUND

Helicobacter pylori infection is a major cause of gastritis and gastric carcinoma. Aspirin has anti-inflammatory and antineoplastic activity. The aim of the present study was to determine the effects of aspirin on H. pylori-induced gastritis and the development of heterotopic proliferative glands.

METHODS

H. pylori strain SS1 was inoculated into the stomachs of Mongolian gerbils. Two weeks after inoculation, the animals were fed with the powder diets containing 0 p.p.m. (n = 10), 150 p.p.m. (n = 10), or 500 p.p.m. (n = 10) aspirin. Mongolian gerbils were killed after 36 weeks of infection. Uninfected Mongolian gerbils (n = 10) were used as controls. Histologic changes, epithelial cell proliferation and apoptosis, and prostaglandin E(2) (PGE(2)) levels of gastric tissue were determined.

RESULTS

H. pylori infection induced gastric inflammation. Administration of aspirin did not change H. pylori-induced gastritis, but alleviated H. pylori-induced hyperplasia and the development of heterotopic proliferative glands. Administration of aspirin accelerated H. pylori-associated apoptosis but decreased H. pylori-associated cell proliferation. In addition, the increased gastric PGE(2) levels due to H. pylori infection were suppressed by treatment with aspirin, especially at the dose of 500 p.p.m.

CONCLUSIONS

Aspirin alleviates H. pylori-induced hyperplasia and the development of heterotopic proliferative glands. Moreover, aspirin increases H. pylori-induced apoptosis. We demonstrated the antineoplastic activities of aspirin in H. pylori-related gastric carcinogenesis.

Washed microbiota transplantation reduces proton pump inhibitor dependency in nonerosive reflux disease

BACKGROUND

The pathogenesis of gastroesophageal reflux disease (GERD) is closely associated with the intestinal bacteria composition and their metabolites.

AIM

To investigate whether washed microbiota transplantation (WMT) improves symptoms of nonerosive reflux disease (NERD) with proton pump inhibitor (PPI) dependency.

METHODS

Patients with recurrent NERD and PPI dependency at the First Affiliated Hospital of Guangdong Pharmaceutical University from 2017 to 2018 were included and divided into a WMT or PPI group treated with PPI with/without WMT. The endpoint was NERD symptom frequency evaluated 1 mo after WMT using reflux disease questionnaire (RDQ) and GERD questionnaire (GERDQ) scores, remission time, PPI dose, and the examination of intestinal mucosal barrier function.

RESULTS

In the WMT (n = 15) and PPI (n = 12) groups, the total remission rate at 1 mo after treatment was 93.3% vs 41.7%. Compared with the PPI group, the WMT group showed better results in GERDQ (P = 0.004) and RDQ (P = 0.003) and in remission months (8 vs 2, P = 0.002). The PPI dose was reduced to some extent for 80% of patients in the WMT group and 33.3% in the PPI group. In 24 patients, intestinal mucosal barrier function was examined before treatment, and changes in the degree of damage were observed in 13 of these patients after treatment. Only one of the 15 patients had minor side effects, including a mushy stool two or three times a day, which resolved on their own after 1 wk.

CONCLUSION

This study is the first to demonstrate that WMT may be safe and effective for relieving NERD symptoms and reducing PPI dependency and recurrence.

Evaluation of a rapid stoolantigen test for the diagnosis of Helicobacter pylori infection in Chinese patients

OBJECTIVE:  To evaluate the accuracy of a rapid assay that wasdeveloped to detect Helicobacter pylori antigen in the stool,using the principle of immunochromatography, in the Chinese population.

METHODS:  Eligible patients without prior treatment of H.pylori were recruited. An in‐house rapid urease test (RUT) andhistology were used as the gold standard. The results of the rapidstool antigen test were compared with the gold standard.

RESULTS:  Valid rapid stool antigen test results for interpretationwere obtained from 94 consecutive patients (mean age: 52.5, range:22−82 years). Sensitivity, specificity, positive predictivevalue, negative predictive value and accuracy were, respectively, 77.5%,87.0%, 81.6%, 83.9% and 83.0%.The test was easy to perform and results were available within 15 min.

CONCLUSION:  The rapid stool antigen test using immunochromatography accuratelydiagnoses H. pylori infection in Chinese patients.

The correlation between intestinal mucosal lesions and hepatic dysfunction in patients without chronic liver disease

Patients with cirrhosis are known to develop small bowel mucosal lesions. However, the occurrence of mucosal lesions in patients with abnormal liver function test results in the absence of chronic liver disease has not been fully evaluated. This study aims to examine the association between small bowel endoscopic lesions and liver dysfunction in patients without confirmed chronic liver disease.Two hundred ninety six consecutive patients who met the selection criteria underwent capsule endoscopy. The severity of the small intestinal mucosal lesions was evaluated quantitatively using the Lewis scoring system, and hepatic dysfunction was evaluated using an algorithm-based combination scoring system with 8 individual serological markers.Small bowel lesions were observed in 121 patients (40.88%). Hepatic dysfunction was significantly more prevalent in patients with small bowel lesions than in those without lesions (33.1%; 40/121 and 5.7%; 10/175, respectively; P < .001). The mean serum ALT and AST levels were significantly higher in patients with small bowel lesions than in those without lesions (P = .007 and P = .004, respectively). The mean scores for AST to Platelet Ratio Index, Forns Index, S-Index, Fibrosis-4 Index and BARD were significantly higher in patients with small bowel lesions than those without lesions. The Lewis score significantly and positively correlated with the Forns Index (P = .008) and the FIB-4 Index (P = .006).There is a close correlation between small intestinal mucosal lesions and hepatic dysfunction. The severity of hepatic dysfunction is directly proportional to the severity of the small intestinal mucosal lesions in patients without confirmed chronic liver disease.

Helicobacter pylori infection--current treatment practice

Helicobacter pylori infection, which is present in 30 - 60% of the population in developed countries and in more than 60% in developing countries, is established to be a major cause of gastritis, peptic ulcer disease and gastric cancer. Eradication therapy has been incorporated into clinical practice over the past 15 years. Treatment regimens include a 2 week bismuth-based triple therapy (a bismuth compound plus metronidazole, tetracycline or amoxycillin), a 1 week proton-pump inhibitor (PPI)-based triple therapy and a 1 week ranitidine bismuth citrate (RBC)-based triple therapy (a PPI or RBC plus any two of the three antibiotics, metronidazole, amoxycillin and clarithromycin). These regimens achieve eradication rates of >> 80%. H. pylori resistance to metronidazole and clarithromycin decreases the clinical efficacy of most regimens, despite the high eradication rates for resistant strains achieved by the RBC-triple therapy in some recent trials. The dose of antibiotics (especially clarithromycin) and the duration of treatment may also influence the eradication rate. Doctors' beliefs impact on clinical practice and, thus, influence the clinical application of eradication therapy. Whereas peptic ulcer disease and primary gastric low-grade B-cell mucosa-associated lymphoid tissue lymphoma (MALToma) have become established as definite indications for eradication therapy, there remain controversies surrounding non-ulcer dyspepsia, gastro-oesophageal reflux disease, atrophic gastritis, intestinal metaplasia, use of non-steroidal anti-inflammatory drugs (NSAIDs) and H. pylori-related extradigestive diseases.

Efficacy of washed microbiota transplantation for therapeutic targets of refractory functional constipation and the influencing factors: a single-center, retrospective, 24-week follow-up study

BACKGROUND

The efficacy of washed microbiota transplantation (WMT) in terms of refractory functional constipation (FC)-related therapeutic targets and influencing factors have not been elucidated. This study aimed to assess the efficacy and influencing factors of WMT in treating refractory FC-related therapeutic targets.

METHODS

The clinical data of patients diagnosed with refractory FC and received with WMT were retrospectively collected. The therapeutic targets included straining, hard stools, incomplete evacuation, a sense of anorectal obstruction, manual maneuvers, and decreased stool frequency. Each target was recorded as 1 (yes) or 0 (no). All patients were followed up for approximately 24 weeks from the end of the first course of WMT. The primary outcomes were the improvement rates for the individual therapeutic targets and the overall response in respect of the therapeutic targets decreased by 2 at weeks 4, 8, and 24. The secondary outcomes were the clinical remission rate (i.e., the proportion of patients with an average of 3 or more spontaneous complete bowel movements per week), clinical improvement rate (i.e., the proportion of patients with an average increase of 1 or more SCBMs/week or patients with remission), stool frequency, Wexner constipation score, Bristol Stool Form Scale (BSFS) score, and adverse events. The factors influencing the efficacy were also analyzed.

RESULTS

Overall, 63 patients with 112 WMT courses were enrolled. The improvement rates at weeks 8 and 24 were 45.6% and 35.0%, 42.9% and 38.6%, 45.0% and 35.7%, 55.6% and 44.4%, and 60.9% and 50.0%, respectively, for straining, hard stools, incomplete evacuation, a sense of anorectal obstruction, and decreased stool frequency. The overall response rates were 49.2%, 50.8%, and 42.9%, respectively, at weeks 4, 8, and 24. The rates of clinical remission and clinical improvement were 54.0% and 68.3%, respectively, at weeks 4. The stool frequency, BSFS score, and Wexner constipation score tended to improve post-WMT. Only 22 mild adverse events were observed during the 112 WMT courses and the follow-up. The number of WMT courses was identified to be the independent factor influencing the efficacy.

CONCLUSIONS

WMT is efficacious in improving refractory FC-related therapeutic targets. The effectiveness of WMT in the management of FC is enhanced with the administration of multiple courses.

Topographic association of gastric epithelial expression of Ki-67, Bax, and Bcl-2 with antralization in the gastric incisura, body, and fundus

OBJECTIVES

Helicobacter pylori (H. pylon) infection seems to induce antralization (ie., gastric mucosal transformation from transitional or body type to antral type), which is strongly associated with gastric atrophy and intestinal metaplasia. The aim of this study was to determine the topographic associations of Ki-67 (a protein expressed in proliferative cells), Bax (a pro-apoptotic protein), and Bcl-2 (an antiapoptotic protein) expression with antralization.

METHODS

In each of 104 patients, eight biopsy specimens were taken from the gastric antrum, incisura, body, and fundus for the determination of H. pylori infection, histological changes, and epithelial expression of Ki-67, Bax, and Bcl-2. A labeling index (LI), i.e., the rate of positive cells over total cells counted, was used for Ki-67 and Bax expression. Bcl-2 overexpression was considered to be present if the rate of Bcl-2 positive cells over total cells counted was > or = 5%.

RESULTS

H. pylori infection was present at the gastric antrum, incisura, body, and fundus in 50, 48, 51, and 49 patients, respectively. Ki-67 LI was greater in the presence vs absence) of H. pylori infection at the antrum (51 vs 40), incisura (47 vs 36), body (43 vs 30), and fundus (41 vs 31) (all p < 0.001). At the incisura, Ki-67 LI was greater (47 vs 32, p < 0.001), Bax LI was lower (22 vs 30, p < 0.05), and prevalence of Bcl-2 overexpression was higher (44% vs 18%, p < 0.001) in the presence (vs absence) of antralization. Compared with normal mucosa, gastric atrophy/intestinal metaplasia were associated with an increased Ki-67 LI and decreased Bax LI at the antrum (49 vs 32 and 15 vs 23, respectively), incisura (47 vs 32 and 15 vs 26, respectively) (all p < 0.001). Bcl-2 overexpression was more frequent in gastric atrophy/intestinal metaplasia at the antrum (56% vs 11%, p < 0.001) and incisura (63% vs 19%, p < 0.001) compared with normal mucosa.

CONCLUSIONS

Antralization at the incisura is topographically associated with increased cell proliferation, reduced Bax expression, and Bcl-2 overexpression, which implies that antralization may be an important histological marker for future cancer risk.

Chemoprevention of gastric cancer: current status

The development of gastric cancer is a multi-factor process. In addition to genetic factors, environmental factors including smoking, low gastric acidity, excessive intake of salt or salty food and low consumption of fresh fruits and vegetables all contribute to the development of gastric cancer. Of particular interest, epidemiological and experimental studies have demonstrated that Helicobacter pylori (H. pylori) infection is causally linked to gastric cancer. Most studies using micronutrient supplementation have failed to demonstrate any preventive effect against the development of gastric cancer. The use of non-steroidal anti-inflammatory drugs has been consistently observed to protect against the development of gastric cancer. Recently, eradication of H. pylori infection by a chemopreventative approach is being studied in a number of trials. Studies using precancerous lesions as an end point of the treatment have produced conflicting and mostly negative results. Trials using cancer as an end point are being cautiously carried out in high-risk populations, and will provide the definitive answer to this important question. In the end, vaccination may be proven to be the optimal strategy in human for the management of H. pylori infection and prevention of gastric cancer.

[Chronic Helicobacter pylori infection induces apoptosis-resistance in gastric epithelial cells]

OBJECTIVE

To establish a cell model by chronically infecting human gastric epithelial cells with H.pylori, and to determine the effect of chronic H.pylori infection on apoptosis of gastric epithelial cells.

METHODS

Human non-tumor gastric epithelial cells GES-1 were cocultured with an H.pylori strain SS1 for 16 weeks, in order to obtain GES-1 "model" cells. Biological characteristics of the model cells including growth, adherence and clone formation were determined. Apoptosis of the "model" cells in response to apoptosis inducers such as H.pylori and other enterobacteria and agents commonly used in the chemotherapy of gastric cancer were measured by flow cytometry.

RESULTS

A cell model of human gastric epithelial cells with chronic H.pylori infection (GES-1 model cells) was successfully established. Apoptosis was dramatically decreased in the "model" cells with and without stimulation by H.pylori and other enterobacteria and some chemotherapeutic agents.

CONCLUSION

Chronic H.pylori infection induces apoptosis resistance in gastric epithelial cells, which may increase the risk of the development of gastric cancer.

Recrudescence of Helicobacter pylori infection in patients with healed duodenal ulcer after treatment with different regimens

OBJECTIVE

To determine the 12-month posttherapy recurrence (recrudescence) of Helicobacter pylori in patients with healed duodenal ulcer after apparent eradication of the organism with anti-H. pylori treatment. The influence of original anti-H. pylori treatment regimens on the recrudescence was also evaluated.

METHODS

One hundred and ninety patients who had duodenal ulcer healed and H. pylori eradicated (as assessed by four routine techniques 4 wk after the end of anti-H. pylori therapy) with one of five regimens were studied. The five regimens were: 1) colloidal bismuth subcitrate (CBS) 120 mg; 2) CBS plus amoxicillin (500 mg); 3) CBS plus metronidazole (400 mg); 4) CBS plus metronidazole and amoxicillin; and 5) CBS plus metronidazole and tetracycline (500 mg). CBS was taken four times daily for 4 wk, and antibiotics were taken three times daily for the first week. The patients were re-endoscoped, and the status of H. pylori, duodenal ulcer, and gastritis was assessed after a period of follow-up (mean 14 months after commencement of treatment).

RESULTS

H. pylori infection recurred in 36 (18.9%) of these patients. Recrudescence rate with monotherapy was 47.1%, with dual therapy 29.2-35% and with triple therapy 9.2-14.3%. Nineteen (52.7%) of the 36 patients with recrudescent infection had ulcer relapse, and the rate for H. pylori-negative patients was 3.2% (5/154).

CONCLUSION

Recrudescence of H. pylori infection after apparent eradication can occur, but it could be that the treatment was only suppressing the organism. The definition of eradication of H. pylori infection may need to be revised, and more sensitive techniques to assess eradication of H. pylori are required.

Normal 24-hour ambulatory proximal and distal gastroesophageal reflux parameters in Chinese

OBJECTIVE

To quantify normal proximal and distal oesophageal acid parameters in healthy Chinese.

DESIGN

Observational study.

SETTING

University teaching hospital, Hong Kong.

SUBJECTS AND METHODS

Twenty healthy adults who were not on medication and were free from gastrointestinal symptoms were recruited by advertisement. Ambulatory oesophageal acid (pH<4) exposure parameters were recorded at distal and proximal sites, 5 and 20 cm, respectively above the lower oesophageal sphincter.

RESULTS

The 95th percentile for reflux parameters assessed in the distal/proximal oesophagus were: percent total time pH<4, 4.6/0.7%; percent upright time pH<4, 7.0/1.1%; percent supine time pH<4, 4.5/0.5%; number of reflux episodes, 73/12; number of reflux episodes with pH<4 for >5 minutes, 4/0; and the longest single acid exposure episode, 11.2/3.0 minutes.

CONCLUSION

Physiological gastroesophageal reflux occurs in healthy Chinese. These initial data provide a preliminary reference range that could be utilised by laboratories studying Chinese subjects.

Natural acquisition and spontaneous elimination of Helicobacter pylori infection: clinical implications

OBJECTIVES

The natural history of Helicobacter pylori infection in humans is not well established. We aimed to systematically review the literature on the natural acquisition and spontaneous elimination of the infection and its clinical consequences.

METHODS

A broad-based MEDLINE and Current Contents search was performed to identify all related publications between 1986 and 1996. Abstracts from recent major conferences that provided adequate data were also included.

RESULTS

The prevalence of H. pylori infection increases with age, the rates being significantly lower in developed countries than in developing countries. However, the overall prevalence is decreasing in both developing and developed countries, which probably is responsible for the steep decline of gastric cancer in some industrialized countries. The natural acquisition of H. pylori infection occurs, for the most part, in childhood, and it appears that the incidence is currently slightly higher in developing countries than in industrialized countries. Spontaneous elimination of the infection also occurs, especially in young children and the elderly. The route of transmission continues to be uncertain, with the best evidence favoring both the gastro-oral and fecal-oral routes. Low socioeconomic status is a major risk factor for acquisition of the infection. Genetics probably plays a role in the acquisition or clearance of H. pylori infection in individuals.

CONCLUSIONS

Low rates of natural acquisition and elimination of the infection in adults suggest that it is worthwhile to eradicate the organism from adults, but there should be further evaluation of the need for eradication of H. pylori in children.

[Association between Helicobacter pylori virulence and duodenal ulcer disease in patients from Hong Kong in China]

OBJECTIVE

A number of putative virulence factors have been postulated to be relevant to the clinical outcome of Helicobacter pylori infection based on strains identified in the western countries. The aim of this study was to investigate the association between genotypes of vacA, cagA and iceA and duodenal ulcer disease in patients from Hong Kong.

METHODS

Seventy-two dyspeptic patients with or without duodenal ulcer disease, with proven H.pylori infection, were studied. Gastric biopsy specimens were analyzed by specific polymerase chain reaction and Southern blot to determine the genotypes of these virulence factors.

RESULTS

Except 6 (8.3%) cases with evidence of multiple infections, all of the remaining 66 cases had vacA signal sequence s1 type strains. Twenty-seven (90%) of the 30 cases with duodenal ulcers were infected with cagA-positive strains, compared with 32 (88.9%) of 36 with non-ulcer dyspepsia (P > 0.05). Similarly, vacA middle region sequences were detected with no significant difference in the two groups, 9 (30.0%) versus 13 (36.1%) for m1b and 21 (70.0%) versus 23 (63.9%) for m2 type. IceA1 subtype was detected in the same frequency in 42 (63.6%) of the 66 cases. Neither cagA nor vacA and iceA were associated with duodenal ulcer disease.

CONCLUSION

No clear differences were found in the distribution of cagA, vacA and iceA genotypes among patients with duodenal ulcer or non-ulcer dyspepsia. The association of these virulence genes and duodenal ulcer disease needs reappraisal, particularly under geographic considerations.