Search PubMed⌕ Search

Biomedical subjects

A Walan

Publications and source records attributed to A Walan.

At least 37 records · Page 2Linked to original sources
PubMed1989

Clinical utility and safety of omeprazole.

Omeprazole inhibits H+,K+-ATPase, the enzyme responsible for the exchange of H+ and K+ in the final step in the acid secretory process within the parietal cell. It has been shown to produce a marked and long-lasting inhibition of acid secretion with a decrease in 24-hour intragastric acidity after repeated daily dosing. Omeprazole has been shown to give significantly higher healing rates than ranitidine or cimetidine in patients with duodenal ulcer and gastric ulcer. Similarly, a more pronounced effect on ulcer symptoms has been observed. In patients with reflux esophagitis, omeprazole has been shown to decrease the time with an acid milieu in the esophagus. Omeprazole has consistently given about twice as high healing rates and faster decrease in symptoms than with ranitidine. In patients with Zollinger-Ellison syndrome, omeprazole has been found to have a rapid and long-lasting effect on acid secretion and acid-induced symptoms.

Animals↗
PubMed1988

Omeprazole.

Explore the source record for details and available documents.

Clinical Trials as Topic↗
PubMed1988

Surface charge and hydrophobicity of Campylobacter jejuni strains in relation to adhesion to epithelial HT-29 cells.

Hydrophobicity and surface charge of clinical isolates of Campylobacter jejuni strains were investigated by aqueous two-phase partitioning (one-step and counter-current distribution), ion exchange chromatography and hydrophobic interaction chromatography. There was a good correlation between the different physico-chemical methods reflecting the same bacterial property. All strains were negatively charged and exposed a hydrophobic surface, but to a varying extent. Bacteria with a high negative surface charge and a weak hydrophobic surface adhered better to human intestinal HT-29 cells than strains with less charge and a more hydrophobic surface. Highest adhesion was shown by a strain differing from all the others in charge properties. It was also found that the tendency to aggregate was higher among the strains showing the greatest degree of adherence.

Bacterial Adhesion↗
PubMed1988

Are endoscopic and/or histologic findings in gastroduodenal mucosa a predictor of clinical outcome in peptic ulcer disease? A 1-year follow-up study after initial healing with either cimetidine or medium-dose antacid.

Patients with duodenal ulcer (DU; n = 79) or prepyloric ulcer (PPU; n = 39) received cimetidine, 400 mg twice daily, or Novaluzid, 10 ml four times daily (acid-neutralizing capacity, 340 mmol/day), in a multicentre, randomized, double-blind trial. Ulcer healing was almost identical with the two treatments at 4, 6, and 12 weeks in the DU group. Cimetidine was significantly more effective than antacids in alleviating symptoms in PPU disease, with no significant difference in ulcer healing. In the PPU group the symptomatic improvement was inferior irrespective of treatment, and there was a significantly lower healing rate at 4 weeks (p less than 0.05) than in the DU group. The relapse rate over a 1-year follow-up period with no therapy did not differ between the two treatment groups or between the two ulcer groups. No factors in history of disease or endoscopic or histologic variables were of predictive value with regard to delayed healing. The macroscopic appearance of the duodenal and antral mucosae improved significantly when ulcers had healed. In the subgroup of about 50% DU patients who experienced a relapse during the 1-year follow-up period, the histologic scoring of duodenitis remained basically unchanged, contrary to the significant improvement seen in the non-relapsing subgroup. The microscopic changes of the antral mucosa from the time of inclusion to healing seen in the PPU patients were of no predictive value with regard to relapse rate.

Adult↗
PubMed1987

Maintenance treatment with cimetidine in peptic ulcer disease for up to 4 years.

A multinational maintenance trial was conducted in 1842 peptic ulcer patients to investigate the efficacy and safety of continuous cimetidine maintenance therapy for up to 4 years. Patients with healed ulcers entered maintenance treatment with a 400-mg bedtime dose of cimetidine. Symptomatic ulcer relapse occurred in 17.2% of patients during the 1st year of treatment, in 9.6% during the 2nd year, and in 8.8% during the 3rd year. In addition to life-table analysis, the monthly prevalence of active ulceration over the 3-year period was examined. The average monthly prevalence rates were 2.1%, 1.8%, and 1.5% for the three successive yearly periods of continued cimetidine treatment. The adverse reactions observed in this study were not different from those previously reported with cimetidine. Moreover, there was a progressive decrease in the incidence of adverse events over the 4 years, thus establishing the long-term safety of continuous cimetidine treatment. It is concluded from this study that cimetidine maintenance treatment not only continues to be effective and safe beyond 1 year but also may reduce the risk of relapse over time.

Adult↗
PubMed1987

The effect of 20 Mg omeprazole daily on serum gastrin, 24-h intragastric acidity, and bile acid concentration in duodenal ulcer patients.

Serum gastrin, 24-h intragastric acidity, and bile acid concentrations were measured during physiologic conditions in 10 patients with duodenal ulcer disease. Omeprazole, 20 mg daily, for 8 days reduced acidity by greater than or equal to 99% in six patients and by 47-54% in four patients. The degree of acid reduction was related to the area under the plasma omeprazole concentration time curve (AUC). Serum gastrin levels were not significantly increased by omeprazole. Intragastric bile acid concentrations were increased by omeprazole, but this seems to be of little importance for the healing of duodenal ulcers.

Adult↗
PubMed1987

Modified sham feeding test after parietal cell vagotomy for juxtapyloric ulcer disease in patients with and without recurrent ulcers.

The mean of individual coefficients of variation of acid output after modified sham feeding was 39% in 22 patients operated on with parietal cell vagotomy. The reproducibility of the interpretation of the sham feeding test as 'positive' or 'negative' was good. An intragastric infusion of a marker to correct for pyloric loss did not increase the accuracy of the test. The prognostic value of the qualitative estimation of the sham feeding test 2 months after operation to predict recurrent ulcer after parietal cell vagotomy was poor in 39 patients studied prospectively over 3 years. With the criterion sham feeding minus basal acid output over 1.0 mmol/30 min as a positive test, 63% of patients with a positive and 24% with a negative test later had recurrent ulcers. The consistency of the interpretation as either positive or negative was low in annual tests during the 3 years of follow-up study. After parietal cell vagotomy the sham-feeding-stimulated acid output was higher in patients with duodenal than in those with prepyloric recurrent ulcers and also in those without recurrences. This indicates that the amount of vagal innervation left after parietal cell vagotomy is of special importance in the occurrence of duodenal ulcer relapse.

Duodenal Ulcer↗
PubMed1986

Pharmacokinetics of [14C]omeprazole in patients with impaired renal function.

Pharmacokinetics of [14C]omeprazole and its metabolites were studied after single intravenous and oral doses of 20 and 40 mg, respectively, to 12 patients with chronic renal insufficiency. Blood samples for determination of total radioactivity, omeprazole, OH-omeprazole, sulfone, and sulfide were taken for 24 hours. Urine was collected over 96 hours for determination of total radioactivity and during the first 24 hours for additional assay of omeprazole and metabolites. The mean systemic availability was 70%. The mean plasma t1/2 of omeprazole was 0.6 hours. Unchanged omeprazole was not measurable in urine. Derived pharmacokinetic constants of intact omeprazole were within the range of those reported in healthy individuals. The accumulated 24-hour excretion of radioactive metabolites was related significantly to creatinine clearance. The cumulative excretion of total radioactivity in urine over 96 hours in percent of given dose varied between 25% and 83%.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1986

A comparison of two different doses of omeprazole versus ranitidine in treatment of duodenal ulcers.

In a study involving three centers, 105 patients with duodenal ulcer proven by endoscopy were randomly assigned to treatment with either the H+, K+, ATPase inhibitor omeprazole (20 mg or 40 mg taken as a single morning dose), or ranitidine (150 mg morning and night). It was a double-blind study using a double-dummy technique. Clinical assessment and laboratory investigations were carried out at 2, 4, and 8 weeks; endoscopy was done at 2 weeks, and if not healed, at 4 and 8 weeks. The patients in the three treatment groups were well matched. Significantly more patients treated with omeprazole healed compared with ranitidine at 2 weeks (p = 0.007) and at 4 weeks (p = 0.007), but there was no statistically significant difference between the two omeprazole groups. Pain was of similar severity at the start in all groups, but patients treated with omeprazole had fewer days with pain (median values being omeprazole 20 mg: 2 days; omeprazole 40 mg: 1 day; ranitidine: 7 days). The difference between the combined omeprazole groups and ranitidine was significant (p less than 0.02). There was also a tendency towards less severe daytime pain on omeprazole during the first week. The difference was statistically significant between omeprazole (40 mg) and ranitidine for days 2-7 (p less than 0.01). No change in laboratory screen attributable to drug treatment occurred. After healing, 79 patients entered a 6-month follow-up study with endoscopy at 3 and 6 months or whenever symptoms occurred. After 6 months relapses occurred in 14/24, 19/23, and 15/25 after 20 mg omeprazole, 40 mg omeprazole, and ranitidine, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Duodenal, prepyloric, and combined duodenal/prepyloric ulcer disease: three distinct entities of juxtapyloric ulcer disease?

One hundred and seven patients with long-standing and severe chronic juxtapyloric ulcer disease were classified in accordance with the location of the present ulcer and previous ulcers into 1) pure duodenal (DU), 2) pure prepyloric (PU), and 3) combined duodenal/prepyloric (DU/PU) or prepyloric/duodenal (PU/DU) ulcer disease. In a prospective follow-up study over a 3-year period after parietal cell vagotomy (n = 39) or during continuous treatment with cimetidine (n = 62) patients with DU had recurrent ulcers located exclusively to the duodenal bulb and patients with PU, exclusively to the prepyloric region. In patients with DU/PU and PU/DU recurrent ulcers occurred on either side of the pylorus. Basal acid and basal pepsin outputs were higher and bile acid in gastric juice was lower in patients with DU than in those with PU. There are a considerable number of patients who possess features of both duodenal and prepyloric ulcer disease. The clinical outcome of both continuous cimetidine treatment and vagotomy in these patients (DU/PU and PU/DU) was less satisfactory than in pure DU. All patients presenting with active DU should therefore be investigated for evidence of previous prepyloric ulceration.

Bile Acids and Salts↗
PubMed1986

Results of short- and long-term cimetidine treatment in patients with juxtapyloric ulcers, with special reference to gastric acid and pepsin secretion.

One hundred and seven patients with active juxtapyloric ulcers and a history of chronic ulcer disease were treated with cimetidine. After ulcer healing 67 patients were selected for medical management, testing the value of cimetidine maintenance treatment. Time to healing was shorter for patients with duodenal ulcers when compared with those with active prepyloric ulcers. Recurrences were fewer for patients with pure duodenal ulcer disease (DUD) when compared with those with active or previous prepyloric ulcer disease (PUD). Patients whose ulcers were slow to heal and those with active or previous prepyloric ulcers (PUD) required a higher dose of cimetidine for effective control of their disease. All patients with slowly healing ulcers (more than 6 weeks) relapsed with 400 mg cimetidine at night. Among patients with relapse 46% with DUD and 31% with PUD were controlled by increasing cimetidine to 400 mg twice daily. Tests of acid secretion were of no value in predicting the rate of ulcer healing or relapse rate. Pepsin secretion studies, however, were of predictive value for patients with DUD but of indeterminate value for patients with PUD. Long-term cimetidine produced a significant decrease in pentagastrin-stimulated pepsin secretion (without treatment) in both patients with and without relapse. No significant changes in acid secretion were observed. As a result of these studies we recommend a cimetidine maintenance dosage of 400 mg twice a day for all patients whose ulcers are slow to heal on 1 g cimetidine a day and in patients with prepyloric ulcer disease regardless of rate of healing.

Cimetidine↗
PubMed1986

24-H study of gastric acidity and bile acid concentration after parietal cell vagotomy.

Intragastric pH and bile acid concentration (BAC) were measured over 24 h in 15 sham-feeding-negative patients, 7 with and 8 without recurrence after parietal cell vagotomy (PCV). Nocturnal acidity was significantly higher (p less than 0.02), and BAC at night significantly lower (p less than 0.02), in the group with recurrent ulcers after PCV. There were no significant differences postoperatively in acidity or BAC between seven patients who had duodenal ulcers preoperatively and eight patients with prepyloric ulcers. High nocturnal acidity may be a predisposing factor for the recurrence of ulcers after PCV.

Adult↗
PubMed1986

Variation of disaccharidase activities in duodenal biopsy specimens.

Multiple biopsy specimens were taken from the duodenal cap and/or from the descending part of the duodenum in patients admitted for routine upper endoscopy, to determine the degree of variation in disaccharidase activity. Four specimens were taken from each site and assayed in pairs. The mean coefficients of variation (CV) of enzymatic activities between duplicate measurements in the same pair of specimens were less than 3.5% and between two pairs of biopsies about 30%. The large variation in disaccharidase activity between assays performed on simultaneously biopsied specimens from the same area of the bulb and the descending part of the duodenum in the same individual implies that single values for enzyme activity must be interpreted with caution.

Adult↗
PubMed1986

Treatment of duodenal ulcer disease. Clinical results with omeprazole.

This paper reviews the results of clinical trials with omeprazole, including UK and Scandinavian multicentre trials. The effect of omeprazole on ulcer healing and symptom relief has been of a magnitude never seen before. The action of the drug has also been so rapid and pronounced that it has not yet been possible to determine the lowest dose which should be recommended to achieve an optimal effect.

Alanine Transaminase↗
PubMed1986

Clinical perspectives of drugs inhibiting acid secretion--H+K+-ATPase inhibitors.

The H+K+-ATPase is supposed to be the terminal step in the acid-secreting pathway in the parietal cell. Omeprazole blocks this enzyme, resulting in a marked inhibition of basal and stimulated acid secretion. With omeprazole 20 mg daily, 24-hour intragastric acidity is decreased by about 90%. Several clinical studies have now been published in which omeprazole has been compared with the H2-receptor antagonists cimetidine and ranitidine. Omeprazole in doses between 20 and 40 mg daily resulted in healing rates between 65% and 82% after treatment for 2 weeks and between 90% and 100% after treatment for 4 weeks. Treatment with omeprazole also gave faster and more pronounced pain relief. One comparative study in gastric ulcer has also been published showing healing rates equal to those with ranitidine. Placebo-controlled trials have also shown very pronounced therapeutic effect in reflux esophagitis. Omeprazole seems to be the drug of choice in Zollinger-Ellison syndrome, giving beneficial clinical effects and pronounced and long-lasting reduction in gastric acid secretion.

Adenosine Triphosphatases↗
PubMed1985

The rate of healing of duodenal ulcers during omeprazole treatment.

We have studied the rate of healing of duodenal ulcers in 44 patients treated with omeprazole, 40 mg once daily for 4 weeks, with or without an 80-mg loading dose on day 1. Fourteen patients (32%) had healed by the end of the 1st week's treatment and a further 27 after a further week (giving a cumulative total of 93%). All patients (100%) had healed by the end of the treatment period. There was no significant difference in healing rate between the two treatment groups. Ulcer symptoms were relieved rapidly, and the drug was well tolerated.

Adult↗