0000000000170366

AUTHOR

G. S. Mela

Are morphology and composition of gallstones related? An x-ray diffraction study

Abstract An x-ray diffractometric technique was used to study the crystalline composition of gallstones removed during surgery from 106 patients. Monohydrate cholesterol was found in the stones of 70 (66%) patients, either alone (33%) or in association with calcium salts (33%). The anhydrous form of cholesterol was found in the stones of 28 (26%) patients, either alone (10%) or in association with calcium salts (16%). These salts (vaterite, aragonite, and calcite) were found in 50% of cases in varying amounts (from 12% to 15% of the stone weight). Eight stones contained no cholesterol: 4 showed an amorphous pattern and 4 were composed of calcium carbonate salts. In 7 of 8 patients with bile…

research product

Head-to-head comparison of 1-week triple regimens combining ranitidine or omeprazole with two antibiotics to eradicate Helicobacter pylori

Background : Triple therapies containing omeprazole and ranitidine have been shown to be equivalent in eradicating H. pylori infection, but have been assessed either separately or head-to-head, only in small trials. Aim : To carry out a large randomized controlled study comparing omeprazole and ranitidine combined with two antibiotic combinations for 1 week. Methods : Three hundred and twenty H. pylori-positive patients were randomly subdivided into four equal-sized groups and received one of the following treatments: OAM = omeprazole 20 mg b.d. + amoxycillin 1 g b.d. + metronidazole 500 mg b.d.; RAM = ranitidine 300 mg b.d. + amoxycillin 1 g b.d. + metronidazole 500 mg b.d.; OAC = omeprazo…

research product

Mealtime versus nighttime acid inhibition

This study was carried out in order to compare the effects of mealtime and bedtime regimens of ranitidine on gastric acidity. Fifteen duodenal ulcer patients in clinical remission were randomized to receive in single-blind fashion either placebo, ranitidine 300 mg at night (2200 hr) or ranitidine 150 mg three times a day given before each of the three daily meals (1800, 0800 and 1200 hr). Over 24 hr, the two active treatments produced a significantly greater acid inhibition than placebo, while the single daily regimen was superior to the three times a day regimen of ranitidine in terms of both rise in pH values (P less than 0.001) and duration of action expressed as time spent above 3.0 pH …

research product

Evaluation of 24-hour gastric acidity in patients with hepatic cirrhosis.

Data from previous studies on gastric acid secretion in patients with hepatic cirrhosis are controversial, due, at least in part, to the possible interference of liver failure and altered gastric mucosal microcirculation on the pharmacological action of the substances used to stimulate the parietal cell. For this reason, we wished to investigate the circadian pattern of gastric acidity by means of continuous 24-hour pH monitoring, which permits measurement of pH fluctuations in a nearly physiological manner and does not require any pharmacological stimulus.Forty-nine patients with liver cirrhosis of different aetiology were recruited for this study. They underwent 24-hour gastric pH-metry w…

research product

A new 1-week therapy for Helicobacter pylori eradication: rani- tidine bismuth citrate plus two antibiotics

Background: One-week triple regimens are currently the most recommended therapy for the eradication of Helicobacter pylori. No previous study has evaluated the efficacy of a short-term regimen combining ranitidine bismuth citrate with two antibiotics. Methods: Seventy-two consecutive H. pylori-positive dyspeptic patients were recruited for this randomized, three-centre, open, parallel-group study. They were subdivided into two groups receiving either ranitidine bismuth citrate 400 mg b.d. + clarithromycin 250 mg b.d. and metronidazole 500 mg b.d. (group A) or ranitidine bismuth citrate 400 mg b.d. + clarithromycin 250 mg b.d. and metronidazole 250 mg q.d.s (group B) for 1 week. H. pylori in…

research product

Eradication of Helicobacter pylori in Recurrent Duodenal Ulcer

research product

Anti-helicobacter regimens

research product

Circadian pattern of intragastric acidity in patients with non-erosive reflux disease (NERD)

Summary Background : Most patients with gastro-oesophageal reflux disease have non-erosive reflux disease. Proton pump inhibitors are less effective than expected in these patients, but no previous study has measured their 24-h gastric pH values. Aims : To evaluate whether there are differences in 24-h intragastric acidity between reflux patients with and without oesophagitis and controls. The influence of Helicobacter pylori on the gastric pH of reflux patients was also assessed. Methods : Sixty-three consecutive patients with gastro-oesophageal reflux disease symptoms who agreed to undergo endoscopy and 24-h pH-metry were recruited. Twenty-five (39%) had erosive oesophagitis and 38 (61%) …

research product

Comparison of 24-h control of gastric acidity by three different dosages of pantoprazole in patients with duodenal ulcer

Background It is now clear that the extent to which gastric acid secretion must be suppressed varies with the clinical condition being treated. Aim To assess the 24-h control of gastric acidity and the individual response variability of three different doses of pantoprazole. Methods Sixty-four duodenal ulcer patients were recruited for this prospective, randomized, multicentre, double-blind, parallel-group study. They were subdivided into three well-matched groups treated with 20 mg o.m., 40 mg o.m. and 40 mg b.d. of pantoprazole, respectively. Endoscopy and intragastric pH monitoring were performed in each patient before and after 14 days of treatment. Results Fifty-five patients were elig…

research product

Acid and gastric metaplasia in the duodenum.

Duodenal and antral mucosal biopsy specimens were obtained from 139 patients with dyspeptic complaints to study the prevalence and extent of gastric metaplasia in the duodenal bulb in relation to Helicobacter pylori (H pylori) infection and duodenal ulcer disease. On logistic regression, the presence and extent of gastric metaplasia was not significantly associated with H pylori infection. The prevalence of gastric metaplasia, however, was found to be higher in patients with current or past evidence of duodenal ulcer disease in comparison with subjects with functional dyspepsia (p = 0.01). A follow up study on 22 patients before and at least one year after eradication of H pylori showed tha…

research product

Circadian gastric acidity in Helicobacter pylori positive ulcer patients with and without gastric metaplasia in the duodenum.

BACKGROUND: The presence of gastric metaplasia allows helicobacter pylori to colonise the duodenum and this condition is thought to be acquired as a response to acid hypersecretion. This functional disorder, however, is present only in a subgroup of duodenal ulcer patients and, in addition, surface gastric metaplasia has been frequently found in the proximal duodenum of normal subjects and patients with non-ulcer dyspepsia, who cannot be certainly considered as acid hypersecretors. AIMS: To clarify the role of acid in inducing gastric type epithelium in the duodenum. This study aimed at assessing whether the pattern of circadian gastric acidity differs between H pylori positive duodenal ulc…

research product

The effects of omeprazole 20 and 40 mg twice daily on intragastric acidity in duodenal ulcer patients.

BACKGROUND: The combination of omeprazole with amoxycillin or clarithromycin is used as treatment against Helicobacter pylori. It seems likely that the antibacterial activity of the antibiotic may be improved by increasing gastric pH towards neutrality, and a twice daily regimen of omeprazole is probably needed. AIM: To assess the effects of twice daily administration of omeprazole 20 and 40 mg. METHODS: Twelve duodenal ulcer patients in remission were randomized to receive in single-blind fashion either placebo, omeprazole 20 mg or omeprazole 40 mg twice daily (08.00 and 20.00 h). On the sixth day of dosing they underwent 24-h gastric pH-metry. RESULTS: Omeprazole 20 and 40 mg b.d. produce…

research product