25 results on '"J-P. Idström"'
Search Results
2. Effect of Omeprazole on Regional and Temporal Variations in Intragastric Acidity
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Robert J. Fraser, David Armstrong, Francesco Viani, J P Idström, Michael Fried, A. L. Blum, Elena F. Verdu, and C. Cederberg
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Male ,Gastric acidity ,medicine.drug_class ,Chemistry ,Stomach ,digestive, oral, and skin physiology ,Gastroenterology ,Proton-pump inhibitor ,Gastric Acidity Determination ,Hydrogen-Ion Concentration ,Pharmacology ,digestive system diseases ,Circadian Rhythm ,Gastric Acid ,medicine.anatomical_structure ,Biochemistry ,medicine ,Humans ,Female ,Single-Blind Method ,Enzyme Inhibitors ,Electrodes ,Omeprazole ,medicine.drug - Abstract
Background: Conventional techniques for measuring gastric acidity have demonstrated the decrease in gastric acidity produced by proton pump inhibitors (PPI); however, such techniques do not detect transient or localized pH changes which may modify the intragastric environment without affecting the therapeutic efficacy of PPIs. Aim: To investigate local and temporal variations in intragastric pH and to test the hypothesis that omeprazole produces prolonged, generalized gastric anacidity (pH >6). Methods: A single-blind study was conducted with triple-point 24-hour gastric pH-metry on days 7, 14 and 21 in 14 healthy, Helicobacter pylori-negative volunteers (7 M; 20–46 years) who received placebo for 7 days, followed by omeprazole 20 mg daily for 14 days. Results: Omeprazole increased the median 24-hour pH significantly in the distal corpus (placebo: 1.3 (95% CI 1.1 to 1.6); omeprazole week 1: 4.0 (2.6–5.0); omeprazole week 2: 4.0 (2.8–4.6)) and at all other gastric recording sites (p < 0.01). At both corpus sites, nocturnal pH was lower and mealtime pH was higher than the non-meal daytime pH during placebo and both omeprazole administration periods; in the antrum, however, the major difference noted was that meal-time pH was higher than non-meal daytime pH. Antral pH was lower during meals and higher at night than proximal corpus pH. During placebo, gastric pH >6.0 was observed at 1 site only for 1.7% (median; 95% CI 0.4–3.3%), at 2 sites simultaneously for 0.24% (0.0–1.0%) and at 3 sites for 0.0% (0.0–0.28%), respectively, of the recording periods; during the second week of omeprazole, the equivalent results were 7.7% (1.4–14.0%), 4.9% (0.21–15.7%) and 4.7% (0.0–9.9%), respectively. Conclusions: Omeprazole, 20 mg daily, does not produce gastric anacidity despite significant increases in median 24-hour pH values. The time-, meal- and site-related variations in gastric pH observed under normal physiological conditions are seen to persist, with prolonged periods of low pH throughout the stomach and preservation of the normal, meal-related rise and nocturnal fall in gastric pH during omeprazole administration.
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- 2002
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3. The effect of ammonia on omeprazole-induced reduction of gastric acidity in subjects with Helicobacter pylori infection
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Michèle Markert, C. Cederberg, Manfred Stolte, Jean E. Crabtree, J P Idström, André L. Blum, David Armstrong, P Bercik, and Elena F. Verdu
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Adult ,Male ,medicine.medical_specialty ,medicine.drug_class ,Spirillaceae ,Proton-pump inhibitor ,Gastroenterology ,Helicobacter Infections ,Ammonia ,Internal medicine ,Humans ,Medicine ,Omeprazole ,Gastric Acidity Determination ,Helicobacter pylori ,Hepatology ,biology ,business.industry ,Stomach ,digestive, oral, and skin physiology ,Hydrogen-Ion Concentration ,Middle Aged ,Anti-Ulcer Agents ,bacterial infections and mycoses ,biology.organism_classification ,digestive system diseases ,medicine.anatomical_structure ,Gastritis ,Gastric acid ,Female ,medicine.symptom ,business ,Follow-Up Studies ,medicine.drug - Abstract
Omeprazole produces a higher intragastric pH during Helicobacter pylori (H. pylori) infection than after cure. We tested the hypothesis that this difference is due to the production of ammonia by H. pylori.Gastric acidity and acid output (AO) were measured overnight in 12 subjects, with and without omeprazole, before and 1 and 6 months after cure of H. pylori infection. Gastric ammonia ([NH3]), total bile acid ([TBA]) and protein concentrations and plasma omeprazole levels were measured.During omeprazole, median AO were 0.0 mmol/h before, 0.86 mmol/h (p = 0.003 vs before cure) at 1 month, and 0.34 mmol/h (p = 0.02) at 6 months after cure; median NH3 output was 0.17 mmol/h before, 0.03 mmol/h (p = 0.002) at 1 month, and 0.02 mmol/h (p = 0.005) at 6 months after cure. AO and NH3 output were similar 1 and 6 months after cure. When corrected for [NH3], AO and gastric pH curves were similar before and after cure. Omeprazole plasma levels increased after cure and gastric [TBA] were unchanged.The higher pH observed before cure of H. pylori during omeprazole administration is attributable, in large part, to ammonia production. Other acid-neutralizing substances and changes in acid secretion may also be important, but duodenogastric reflux and omeprazole pharmacokinetics are not involved.
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- 2000
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4. The effect of intra-gastric acidity and flora on the concentration of N-nitroso compounds in the stomach
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J P Idström, David Armstrong, C. Cederberg, André L. Blum, Francesco Viani, Hans H. Siegrist, Brigitte Pignatelli, Elena F. Verdu, and Michael Fried
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Adult ,Male ,medicine.medical_specialty ,Flora ,Gastric acidity ,Nitroso Compounds ,Atrophic gastritis ,Gastroenterology ,Bacterial colonization ,Reference Values ,Stomach Neoplasms ,Internal medicine ,medicine ,Humans ,Single-Blind Method ,Enzyme Inhibitors ,Gastric carcinogenesis ,Omeprazole ,Hepatology ,business.industry ,Achlorhydria ,Stomach ,digestive, oral, and skin physiology ,Hydrogen-Ion Concentration ,medicine.disease ,digestive system diseases ,medicine.anatomical_structure ,Biochemistry ,Carcinogens ,Female ,business ,medicine.drug - Abstract
Correa's hypothesis proposes that gastric carcinogenesis is due to atrophic gastritis and hypochlorhydria which permit gastric bacterial colonization, the reduction of dietary nitrates to nitrites and the formation of potentially carcinogenic N-nitroso compounds (NOCs).To test the hypothesis that omeprazole-induced hypochlorhydria is associated with increased intra-gastric concentrations of nitrate-reducing bacteria (NRB), nitrites and NOCs.Single-blind study in healthy volunteers.Fourteen healthy subjects (seven female, mean age 24 years), free of Helicobacter pylori infection, received a one-week course of placebo followed by a two-week course of omeprazole, 20 mg daily.Fasted gastric samples, aspirated using a sterile double-lumen nasogastric tube at the end of the 1 st week (placebo) and the 2nd and 3rd weeks (omeprazole), were cultured aerobically and anaerobically; gastric pH and intra-gastric concentrations of nitrates, nitrites and NOCs were also determined.After weeks 1, 2 and 3, the intra-gastric concentrations of nitrate-reducing bacteria exceeded 10(5) colony-forming units (c.f.u.)/ml in 3, 7 and 9 subjects, respectively (P0.05). A gastric pH greater than 4.0 was associated with increased NRB (P0.05); however, neither increased gastric pH nor increased NRB, alone or in combination, was associated with increased intra-gastric concentrations of nitrites or NOCs (P0.05).A two-week increase in gastric pH in healthy, H. pylori-negative subjects was associated with increased intra-gastric concentrations of nitrate-reducing bacteria but not of nitrites or N-nitroso compounds. These data suggest that reduced gastric acid secretion is not a necessary precursor to the formation of carcinogenic N-nitroso compounds and that other mechanisms should be invoked to explain gastric carcinogenesis.
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- 2000
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5. High Concentrations of Ammonia, But Not Volatile Amines, in Gastric Juice of Subjects with Helicobacter pylori Infection
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C. Cederberg, David Armstrong, Premysl Bercik, Elena F. Verdu, J P Idström, Lionella Sabovcikova, and André L. Blum
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Adult ,Male ,Helicobacter pylori infection ,Serial dilution ,Biosensing Techniques ,Helicobacter Infections ,Microbiology ,Ammonia ,chemistry.chemical_compound ,In vivo ,Humans ,Amines ,chemistry.chemical_classification ,Gastric Juice ,Chromatography ,Helicobacter pylori ,biology ,Gastroenterology ,General Medicine ,Middle Aged ,biology.organism_classification ,Dilution ,Infectious Diseases ,Enzyme ,chemistry ,Female - Abstract
Background.~ Helicobacter pylori (H. pylori) produces large amounts of ammonia. Based on higher readings obtained with an ammonia-sensitive electrode when compared to a specific enzymatic assay, it has been claimed that H. pylori also produces potentially toxic volatile amines. Method. We measured ammonia concentrations (NH3) in gastric aspirates from 11 H. pylori positive subjects (22–40 y, 6~ m), using an ammonia electrode sensitive to ammonia and amines, and an enzymatic assay specific for ammonia. Continuous aspiration was performed overnight and 220 aspirates were analyzed before and 6~weeks after cure of H. pylori. Gastric samples were diluted 1:3 (before cure) and 1:1 (after cure) according to dilution curves constructed prior to the assays. Results. Median (95% CI) NH3 detected by the elec-trode/enzymatic assay were 4.34~m m[4.12–4.61]/4.50~m m [4.28–4.68] (p~>~.05) before cure and 0.54~m m[0.42–0.60]/0.73~m m[0.71–0.81] after cure (p~>~.05). Intra-class correlation coefficient between the two methods was 0.91 before cure and 0.90 after cure (p~
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- 1998
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6. One-week low-dose triple therapy for Helicobacter pylori is sufficient for relief from symptoms and healing of duodenal ulcers
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Ulrich Peitz, J.‐P. Idström, Joachim Labenz, R. J. Adamek, B Tillenburg, and G. Börsch
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Male ,medicine.medical_specialty ,Time Factors ,Rapid urease test ,Placebo ,Gastroenterology ,Helicobacter Infections ,Double-Blind Method ,Clarithromycin ,Metronidazole ,Internal medicine ,medicine ,Humans ,Pharmacology (medical) ,Omeprazole ,Antibacterial agent ,Breath test ,Helicobacter pylori ,Hepatology ,biology ,medicine.diagnostic_test ,business.industry ,Anti-ulcer Agent ,Middle Aged ,Anti-Ulcer Agents ,biology.organism_classification ,Anti-Bacterial Agents ,Duodenal Ulcer ,Drug Therapy, Combination ,Female ,business ,medicine.drug - Abstract
Aim: To test the hypothesis that 1-week low-dose triple therapy for H. pylori is sufficient for relief from dyspeptic symptoms and healing of duodenal ulcers. Methods: Fifty-nine out-patients with duodenal ulcers and positive rapid urease test participated in this randomized, double-blind, two-centre study. All patients were treated for 1 week with omeprazole 20 mg b.d., clarithromycin 250 mg b.d. and metronidazole 400 mg b.d. In a double-blind fashion, patients were then randomly treated for another 3 weeks with either omeprazole 20 mg once daily or an identical-looking placebo. Patients were investigated endoscopically before treatment for H. pylori, after 2 weeks and after 4 weeks. H. pylori infection was assessed by a 13C-urea breath test at the time of enrolment and 4 weeks after cessation of any study medication. Results: Fifty-two patients were included in the ‘all patients treated’ analysis of efficacy. The overall H. pylori cure rate was 96% (95% CI=87–100%), with no difference between the treatment groups. After 2 weeks duodenal ulcer healing was confirmed in 91% (95% CI=80–100%) of patients treated with omeprazole and in 76% (95% CI=60–91%) in the placebo group (P=0.14). After 4 weeks all ulcers had healed. Relief from dyspeptic symptoms and adverse events (13.8 and 16.7%) did not differ between the treatment groups. Conclusions: One-week low-dose triple therapy consisting of omeprazole, clarithromycin and metronidazole is a highly effective and well-tolerated approach to the cure of H. pylori infection in patients with a duodenal ulcer. Our data suggest that continuation of antisecretory drug therapy beyond anti-H. pylori therapy is actually excessive regarding relief from dyspeptic symptoms and healing of duodenal ulcers.
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- 1997
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7. Eradication of Helicobacter pylori Using One-week Triple Therapies Combining Omeprazole with Two Antimicrobials: The MACH I Study
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Karna Dev Bardhan, Ekkehard Bayerdörffer, Sander Veldhuyzen van Zanten, J P Idström, Tore Lind, C. Cederberg, Naoki Chiba, Colm O'Morain, Marc Bradette, Robin C. Spiller, Michael Wrangstadh, and P. Unge
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Male ,medicine.medical_specialty ,medicine.drug_class ,Proton-pump inhibitor ,Placebo ,Gastroenterology ,Drug Administration Schedule ,Helicobacter Infections ,Pharmacotherapy ,Double-Blind Method ,Clarithromycin ,Metronidazole ,Internal medicine ,medicine ,Humans ,Enzyme Inhibitors ,Omeprazole ,Helicobacter pylori ,biology ,business.industry ,Amoxicillin ,General Medicine ,Middle Aged ,Anti-Ulcer Agents ,biology.organism_classification ,Treatment Outcome ,Infectious Diseases ,Duodenal Ulcer ,Gastritis ,Drug Therapy, Combination ,Female ,business ,medicine.drug - Abstract
The discovery of Helicobacter pylori (H. pylori) opened the doors to new insight and therapy for peptic ulcer disease. Earlier eradication treatment modalities based on bismuth compounds, with or without additional antimicrobials, were not well accepted mainly because of the, at least hypothetical, risks for neurological and/or renal side effects. The first proton pump inhibitor, omeprazole, had been proven as a very effective short-term anti-ulcer therapy, but after withdrawal of the drug, the recurrence rate was high. theoretically, acid suppression was believed to increase the H. pylori infestation as the environment became more neutral. On the other hand, acid suppression could increase the effect of acid labile antimicrobials. This was not investigated before the studies presented in this thesis were performed.A small pilot study (Paper I) in 24 patients showed that 7 out of 8 patients treated for fourteen days with omeprazole 40 mg o.m. + amoxicillin 750 mg b.i.d. were cleared of H. pylori, while it remained in 7/8 patients on omeprazole as monotherapy and in 2/7 patients on amoxicillin as monotherapy. However, the eradication rates 4 weeks after treatment were 5/8, 0/8 and 1/7 in the three groups, respectively. These results were confirmed in a large study (Paper II) comprising 248 consecutive patients with active duodenal ulcer disease. All had an initial treatment period for two weeks with omeprazole 40 mg o.m., followed by continued omeprazole in combination with amoxicillin 750 mg b.i.d. or amoxicillin placebo for a further two weeks. In the dual therapy group, 54% of patients were H. pylori eradicated compared to 4% in the omeprazole mono therapy group. Furthermore, the duodenal ulcer relapse rate was significantly lower in the combination group compared to the monotherapy group (p
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- 1996
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8. Effect of omeprazole on the distribution of metronidazole, amoxicillin, and clarithromycin in human gastric juice
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J-P. Idström, Paul N. Shaw, A. F. Goddard, C Cederberg, M.J. Jessa, David A. Barrett, and Robin C. Spiller
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Adult ,Male ,Saliva ,medicine.drug_class ,Antibiotics ,Penicillins ,Pharmacology ,Gastric Acid ,Double-Blind Method ,Clarithromycin ,Metronidazole ,medicine ,Humans ,Tissue Distribution ,Omeprazole ,Antibacterial agent ,Cross-Over Studies ,Gastric Juice ,Hepatology ,biology ,business.industry ,Gastroenterology ,Amoxicillin ,Helicobacter pylori ,Anti-Ulcer Agents ,biology.organism_classification ,Anti-Bacterial Agents ,Gastric Mucosa ,business ,medicine.drug - Abstract
BACKGROUND & AIMS: The mechanism by which antimicrobial therapy against Helicobacter pylori is enhanced by acid suppression is unknown. The aim of this study was to investigate the effect of omeprazole on gastric juice, plasma, and saliva concentrations of metronidazole, amoxicillin, and clarithromycin. METHODS: Single doses of antibiotic were administered intravenously to 24 healthy men (each antibiotic to 8 subjects) while taking placebo or omeprazole. Antibiotic concentrations were measured in gastric juice, plasma, and saliva. The pharmacokinetic parameters gastric clearance and gastric transfer fraction were calculated for each antibiotic. RESULTS: In the omeprazole group compared with the placebo group, mean maximum antibiotic gastric juice concentrations (in milligram per liter) of metronidazole decreased from 33.6 to 8.3 (P = 0.0001), whereas those of clarithromycin were unchanged, and those of amoxicillin increased from 0.13 to 0.68 (P = 0.02). Omeprazole increased salivary concentrations of metronidazole (P = 0.02) but had no effect on clarithromycin concentrations (no amoxicillin was detectable in saliva). CONCLUSIONS: Omeprazole decreases the intragastric concentrations of metronidazole by reducing acid secretion and increases intragastric concentrations of amoxicillin partly by reducing gastric juice volume. Novel pharmacokinetic parameters have been described that provide an insight into the mechanisms underlying drug transfer across the blood-stomach barrier. (Gastroenterology 1996 Aug;111(2):358-67)
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- 1996
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9. Helicobacter pylori augments the pH-increasing effect of omeprazole in patients with duodenal ulcer
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A. L. Blum, Manfred Stolte, Elena F. Verdu, B Tillenburg, G Borsch, Joachim Labenz, J P Idström, and Ulrich Peitz
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medicine.medical_specialty ,Chemotherapy ,Hepatology ,biology ,medicine.diagnostic_test ,business.industry ,Spirillaceae ,medicine.medical_treatment ,Urea breath test ,Gastroenterology ,Rapid urease test ,Helicobacter pylori ,biology.organism_classification ,medicine.anatomical_structure ,Internal medicine ,Duodenum ,Medicine ,In patient ,business ,Omeprazole ,medicine.drug - Abstract
BACKGROUND & AIMS: Omeprazole is less effective in healthy subjects than in patients with duodenal ulcers. The aim of this study was to determine whether Helicobacter pylori augments the pH-increasing effect of omeprazole in patients with duodenal ulcers. METHODS: In 16 patients with duodenal ulcers, baseline intragastric acidity was measured before and 4-6 weeks after the cure of H. pylori infection. In 17 patients with duodenal ulcers, 24-hour pH metry was performed during treatment with 20 mg omeprazole once daily before as well as after eradication of H. pylori. Intragastric acidity was measured using a glass electrode placed 5 cm below the cardia. H. pylori infection was assessed by [13C] urea breath test, culture, histology, and rapid urease test. RESULTS: H. pylori eradication resulted in marked decrease of the pH-increasing effect of omeprazole (24-hour median gastric pH, 5.5 vs. 3.0; P
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- 1996
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10. Gastrointestinal Transit of Amoxicillin Modified-Release Tablets and a Placebo Tablet Including Pharmacokinetic Assessments of Amoxicillin
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A. Svenheden, Magne Alpsten, J. Gottfries, B. Bake, A. Larsson, and J.-P. Idström
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Adult ,Male ,Biological Availability ,Penicillins ,Pharmacology ,Placebo ,Dosage form ,Placebos ,Eating ,Pharmacokinetics ,medicine ,Humans ,Gastrointestinal Transit ,Omeprazole ,Antibacterial agent ,Cross-Over Studies ,Gastric emptying ,business.industry ,digestive, oral, and skin physiology ,Gastroenterology ,Amoxicillin ,Fasting ,Crossover study ,Bioavailability ,Gastric Emptying ,Delayed-Action Preparations ,Drug Monitoring ,business ,medicine.drug - Abstract
We have investigated the gastrointestinal transit time of, the influence of food intake on, the disintegration of, and the pharmacokinetics of amoxicillin in a modified-release form.Radiolabelled modified-release tablets of amoxicillin and placebo tablets were administered, in an open three-way, randomized, crossover design, as single doses during omeprazole treatment, to six male healthy subjects during fasting and non-fasting conditions. Radioscintigraphic images and plasma samples were obtained.The estimated mean (and range) gastric emptying time of the modified-release tablet after drug administration was 0.3 h (0.1-1.0 h) during fasting conditions, 4.3 h (1.7-5.0 h) after a light breakfast, and 4.9 h (1.9-18.0 h) after a heavy breakfast. The small-intestinal transit time during fasting conditions was 4.7 h (2.9-6.9 h) and was not significantly changed after light or heavy breakfast intake. The relative bioavailability of the modified-release tablet was 55%, compared with a commercially available amoxicillin immediate-release tablet.The modified-release tablet of amoxicillin administered postprandially apparently increases the amoxicillin release time in the stomach. The relevance of its use for anti-H. pylori treatment can be questioned.
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- 1996
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11. Effect of curing Helicobacter pylori infection on intragastric pH during treatment with omeprazole
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Manfred Stolte, J P Idström, Gian Dorta, Joachim Labenz, David Armstrong, G Borsch, A. L. Blum, and Elena F. Verdu
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Adult ,Male ,medicine.medical_specialty ,Helicobacter pylori infection ,medicine.medical_treatment ,Spirillaceae ,Gastroenterology ,Helicobacter Infections ,Gastric Acid ,Internal medicine ,medicine ,Humans ,Omeprazole ,Chemotherapy ,Helicobacter pylori ,biology ,business.industry ,Anti-ulcer Agent ,Stomach ,Gastric Acidity Determination ,Hydrogen-Ion Concentration ,Anti-Ulcer Agents ,biology.organism_classification ,Antibodies, Bacterial ,medicine.anatomical_structure ,Breath Tests ,Gastric acid ,Female ,business ,Research Article ,medicine.drug - Abstract
It has been shown that omeprazole treatment produces higher intragastric pH values in Helicobacter pylori positive subjects than in H pylori negative subjects. This study aimed to investigate the effect of curing H pylori on the intragastric pH in both the presence and absence of omeprazole therapy. Twenty four hour intragastric pH recordings were performed before and after a one week course of omeprazole (20 mg once daily) in 18 H pylori positive subjects and were repeated after the infection had been cured. In the absence of omeprazole, the total 24 hour pH values before cure did not differ from those afterwards. During omeprazole treatment the 24 hour pH values were much higher before (median (95% CI) 5.4: 4.3, 6.0), than after cure of infection (3.6: 2.1, 4.4; p < 0.001). The omeprazole induced fall in H+ activity before cure of H pylori did not, however, differ from that afterwards. It is concluded that the apparently greater antisecretory effect of omeprazole during H pylori infection may be a result of the production of acid neutralising compounds by the H pylori. Although a direct interaction between H pylori and omeprazole cannot be excluded, it seems unlikely.
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- 1995
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12. Effect of Helicobacter pylori status on intragastric pH during treatment with omeprazole
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David Armstrong, Robert J. Fraser, J P Idström, A. L. Blum, Francesco Viani, Elena F. Verdu, and C. Cederberg
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Adult ,Male ,medicine.medical_specialty ,Time Factors ,Spirillaceae ,Placebo ,Gastroenterology ,Helicobacter Infections ,Double-Blind Method ,Internal medicine ,medicine ,Humans ,Single-Blind Method ,Antrum ,Omeprazole ,Gastric Acidity Determination ,Cross-Over Studies ,Helicobacter pylori ,biology ,business.industry ,Stomach ,Hydrogen-Ion Concentration ,Middle Aged ,bacterial infections and mycoses ,biology.organism_classification ,Crossover study ,medicine.anatomical_structure ,Breath Tests ,Female ,business ,Research Article ,medicine.drug - Abstract
To test the hypothesis that Helicobacter pylori infection is associated with a decreased intragastric acidity during omeprazole therapy, ambulatory 24 hour dual point gastric pH recordings were performed in 18 H pylori positive and 14 H pylori negative subjects. There was a four to six week washout period between the two pH recordings made in each subject after one week courses of placebo or omeprazole, 20 mg daily. During placebo, median 24 hour pH values were not different in the corpus (H pylori positive = 1.5, negative = 1.4; p = 0.9) or antrum (H pylori positive = 1.3, negative = 1.2; p = 0.1). However, during omeprazole treatment, median 24 hour pH values were higher in H pylori positive subjects, both in the corpus (H pylori positive = 5.5, negative = 4.0; p = 0.001) and antrum (H pylori positive = 5.5, negative = 3.5; p = 0.0004). During placebo treatment, the only difference between the two groups was a higher later nocturnal pH in the antrum in the H pylori positive group. During omeprazole treatment, gastric pH was higher both in the corpus and in the antrum in the H pylori positive group for all periods, except for mealtime in the corpus. These data indicate that omeprazole produces a greater decrease in gastric acidity in subjects with H pylori infection than in those who are H pylori negative. It is not, however, known whether there is a causal relationship between H pylori infection and increased omeprazole efficacy.
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- 1995
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13. Efficacy of omeprazole one year after cure of Helicobacter pylori infection in duodenal ulcer patients
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J, Labenz, B, Tillenburg, U, Peitz, G, Börsch, J P, Idström, E, Verdú, M, Stolte, and A L, Blum
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Adult ,Male ,Time Factors ,Helicobacter pylori ,Biopsy ,Remission Induction ,Gastric Acidity Determination ,Hydrogen-Ion Concentration ,Middle Aged ,Anti-Ulcer Agents ,Helicobacter Infections ,Gastric Mucosa ,Duodenal Ulcer ,Humans ,Female ,Omeprazole ,Follow-Up Studies - Abstract
We have previously shown that, in duodenal ulcer patients, pH control by omeprazole is less pronounced after cure of Helicobacter pylori infection. The present study was designed to test the hypothesis that this response to omeprazole persists 1 yr after cure of H. pylori infection.In 12 duodenal ulcer patients, intragastric acidity was measured with a glass electrode during treatment with omeprazole (20 mg) once daily before, and 4-6 wk and 1 yr after, cure of H. pylori infection. H. pylori infection was assessed by [13C]urea breath test, culture, histology (Warthin Starry stain), and rapid urease test.Cure of H. pylori infection resulted in a lowered pH during omeprazole treatment. This effect persisted after 1 yr. Median 24-h gastric pH before H. pylori treatment was 5.6; 4-6 wk after cure of the infection it was 2.9 (p = 0.003), and 1 yr after cure of the infection it remained unchanged (pH = 2.5; p = 0.5). Accordingly, twice as much time was spent above pH 3 and pH 4 before H. pylori treatment than 1 or 12 months after cure (percent of timeor = pH 3: 82.7 vs. 49.7 vs. 43.1; percent of timeor = pH 4: 72.7 vs. 38.3 vs. 26.4).In duodenal ulcer patients, cure of H. pylori infection resulted in a marked rapid and persistent decrease of the pH increasing effect of omeprazole. Therefore, H. pylori is a determinant of the pH achieved in response to omeprazole treatment in duodenal ulcer patients.
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- 1997
14. Intragastric pH during treatment with omeprazole: role of Helicobacter pylori and H. pylori-associated gastritis
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Elena F. Verdu, A. L. Blum, J P Idström, Joachim Labenz, G Borsch, David Armstrong, and M. Stolte
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Adult ,Male ,medicine.medical_specialty ,Helicobacter pylori infection ,Spirillaceae ,medicine.medical_treatment ,Radioimmunoassay ,Gastroenterology ,Antral gastritis ,Helicobacter Infections ,Internal medicine ,Gastrins ,Gastroscopy ,Medicine ,Humans ,Antrum ,Omeprazole ,Chemotherapy ,biology ,Helicobacter pylori ,business.industry ,Hydrogen-Ion Concentration ,biology.organism_classification ,Anti-Ulcer Agents ,Gastric Mucosa ,Gastritis ,Female ,medicine.symptom ,business ,medicine.drug - Abstract
Omeprazole treatment produces lower intragastric pH values 4 weeks after cure of Helicobacter pylori infection than before. We therefore investigated the effect of healing H. pylori-associated gastritis on intragastric pH in the presence and in the absence of omeprazole therapy.Before and on day 8 of omeprazole, 20 mg once daily, 24-h intragastric pH-recordings were performed in 14 subjects with H. pylori infection and repeated 4 and 52 weeks after cure of infection. Gastritis severity in corpus and antrum was graded by using a modified Sydney system.In the absence of omeprazole administration, median 24-h pH values before cure did not differ from those 4 and 52 weeks after cure. On day 8 of omeprazole administration, 24-h pH values were much higher before cure (median, 5.15; 95% confidence interval (CI), 4.3-6.0) than 4 weeks (3.6; 2.1-4.4; P0.001) and 52 weeks after cure (3.0; 2.1-4.4; P0.001). The activity of corpus and antral gastritis was not associated with the magnitude of H+ change induced by omeprazole.The increased pH produced by omeprazole during H. pylori infection is likely to be due to neutralizing substances produced by H. pylori and not to H. pylori-induced gastritis.
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- 1996
15. Effect of omeprazole on intragastric bacterial counts, nitrates, nitrites, and N-nitroso compounds
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Hans H. Siegrist, C. Cederberg, Elena F. Verdu, J P Idström, Brigitte Pignatelli, Francesco Viani, André L. Blum, David Armstrong, M. Fried, and Robert J. Fraser
- Subjects
Adult ,Male ,Nitroso Compounds ,medicine.drug_class ,Proton-pump inhibitor ,Pharmacology ,Placebo ,chemistry.chemical_compound ,medicine ,Humans ,Single-Blind Method ,Nitrite ,Carcinogen ,Omeprazole ,Nitrites ,Colony-forming unit ,Gastric Juice ,Nitrates ,Bacteria ,Chemistry ,Gastroenterology ,Hydrogen-Ion Concentration ,Middle Aged ,Biochemistry ,Gastric acid ,Female ,medicine.drug ,Research Article - Abstract
Previous studies have suggested that profound inhibition of gastric acid secretion may increase exposure to potentially carcinogenic N-nitroso compounds. The aim of this study was to find out if the proton pump inhibitor omeprazole (20 mg daily) is associated with increased concentrations of potentially carcinogenic N-nitroso compounds in gastric juice. The volume of gastric contents, number of bacteria, and concentrations of nitrates, nitrites, and N-nitroso compounds was determined in gastric aspirates obtained after an overnight fast in 14 healthy volunteers (7M:7F) after one week of treatment with placebo, and one and two weeks' treatment with omeprazole. Median bacterial concentrations were 1.0 x 10(4) (range 5.0 x 10(3)-5.0 x 10(6)) colony forming units (CFU)/ml after one weeks' treatment with placebo and increased significantly to 4.0 x 10(5) (0-3.3 x 10(7)) CFU/ml after two weeks' treatment with omeprazole (p < 0.05). A similar increase was seen in the concentration of nitrate reducing bacteria. There was no difference in the volume of gastric aspirates after treatment with omeprazole when compared with placebo (65 (29-155) ml v 42 (19-194) ml). The concentration of N-nitroso compounds was 0.13 (0-1.0) mumol/l after two weeks of omeprazole, which was not significantly different from that seen with placebo (0.15 (0-0.61) mumol/l). There was also no increase in the concentrations of nitrates or nitrites. It is concluded that omeprazole (20 mg once daily) for two weeks in healthy volunteers is associated with gastric bacterial proliferation but does not increase concentrations of N-nitroso compounds.
- Published
- 1994
16. Energetics of nutrition and polyamine-related tumor growth alterations in experimental cancer
- Author
-
J. P. Idström, K. Lundholm, Bengt Gustavsson, L. Hafström, Staffan Edström, Per Lindnér, B. Soussi, Thomas Westin, and E. Lydén
- Subjects
Male ,Cancer Research ,medicine.medical_specialty ,Eflornithine ,Magnetic Resonance Spectroscopy ,Cell division ,Phosphocreatine ,Ratón ,Biology ,Ornithine Decarboxylase ,chemistry.chemical_compound ,Eating ,Mice ,Adenosine Triphosphate ,In vivo ,Internal medicine ,medicine ,Animals ,Energy charge ,chemistry.chemical_classification ,DNA synthesis ,Cancer ,Phosphorus Isotopes ,Phosphorus ,Organ Size ,medicine.disease ,Mice, Inbred C57BL ,Endocrinology ,Enzyme ,Oncology ,chemistry ,Starvation ,Female ,Sarcoma, Experimental ,Polyamine ,Energy Metabolism ,Methylcholanthrene ,Research Article - Abstract
The aim of this study was to evaluate whether food intake modulates experimental tumour growth by acute alterations in the energy state and blood flow of the tumour, and if so whether such changes are related to alterations in the enzyme ornithinedecarboxylase (ODC) and DNA synthesis. Inbred mice (C57BL/J) bearing a syngeneic undifferentiated and rapidly growing tumour were used. The tumour levels of high energy phosphates were measured in vivo by 31-P-NMR spectroscopy and biochemically following tissue extraction. DNA synthesis was estimated by measuring the incorporation of bromodeoxy-uridine into tumour DNA. Difluoro-methylornithine (DFMO) was used to inhibit ODC-activity. Tumour blood flow was estimated by a 132Xe local clearance technique. Tumour progression was associated with a significant decrease in tumour tissue high energy phosphates. Acute starvation decreased DNA-synthesis and tumour energy charge as well as its PCr/Pi which were rapidly normalised during subsequent refeeding. These changes were related to similar alterations in tumour blood flow. The inorganic phosphate (Pi) resonance and the resonances in the phosphomonoester (PME) region were considerably increased in tumour tissue. Inhibition of ODC-activity by DFMO decreased DNA-synthesis, which was associated with a secondary increase in tumour high energy phosphates probably due to a lowered energy demand for tumour cell division. The results demonstrate that host undernutrition was translated into retarded tumour growth associated with a decrease in the energy state and blood flow of the tumour. The results have bearing for the evaluation and planning of all treatment protocols with potential influence on food intake in experimental tumour-bearing animals.
- Published
- 1993
17. 24-hour intragastric acidity and plasma gastrin during long-term treatment with omeprazole or ranitidine in patients with reflux esophagitis
- Author
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Hans Lönroth, Tore Lind, Lars Lundell, C. Cederberg, J.-P. Idström, and Lars Olbe
- Subjects
Adult ,Male ,medicine.medical_specialty ,Time Factors ,Ranitidine ,Gastroenterology ,Internal medicine ,Gastrins ,medicine ,Humans ,Reflux esophagitis ,Esophagitis, Peptic ,Omeprazole ,Gastrin ,Morning ,Aged ,Aged, 80 and over ,business.industry ,Stomach ,Gastric Acidity Determination ,Middle Aged ,medicine.disease ,Circadian Rhythm ,medicine.anatomical_structure ,Postprandial ,Female ,business ,Esophagitis ,medicine.drug - Abstract
The reduction in intragastric acidity and the subsequent increase in plasma gastrin were compared during long-term treatment with either omeprazole or ranitidine in 19 patients with erosive reflux esophagitis. The patients received 40 mg omeprazole in the morning or 300 mg ranitidine twice daily. After healing, half the dose was given as maintenance treatment for 1 year. Intragastric acidity and plasma gastrin were measured 24 h before entry and monthly with the high dose and after 1, 6, and 12 months with the low dose. Omeprazole reduced intragastric acidity more effectively than ranitidine (p less than 0.001). This difference in efficacy was more pronounced during the daytime. Plasma gastrin increased more after omeprazole than after ranitidine (p less than 0.01), and both drugs showed a normal postprandial response and approached fasting levels before the next dose. During long-term treatment with 20 mg omeprazole in the morning no progressive alterations were observed in 24-h intragastric acidity or plasma gastrin.
- Published
- 1991
18. Effect of omeprazole on the distribution of antibiotics in gastric juice
- Author
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J-P. Idström, M. Wrangstadh, A. F. Goddard, Robin C. Spiller, Paul N. Shaw, C. Wason, David A. Barrett, and M.J. Jessa
- Subjects
medicine.medical_specialty ,Hepatology ,medicine.drug_class ,business.industry ,Internal medicine ,Antibiotics ,Gastroenterology ,medicine ,Distribution (pharmacology) ,business ,Omeprazole ,medicine.drug - Published
- 1995
- Full Text
- View/download PDF
19. Amoxicillin, clarithromycin, erythromycin, roxithromycin in combination with omeprazole for eradication of H. pylori
- Author
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H Hallberg, Tore Lind, M. Wrangstadh, A. Jonsson, and J-P. Idström
- Subjects
medicine.medical_specialty ,Hepatology ,business.industry ,Roxithromycin ,Gastroenterology ,Erythromycin ,Amoxicillin ,Clarithromycin ,Internal medicine ,medicine ,business ,Omeprazole ,medicine.drug - Published
- 1995
- Full Text
- View/download PDF
20. Effect of curing Helicobacter pylori (HP) infection on intragastric pH during omeprazole treatment
- Author
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Gian Dorta, J P Idström, G Borsch, A. L. Blum, Elena F. Verdu, Joachim Labenz, Manfred Stolte, and David Armstrong
- Subjects
medicine.medical_specialty ,Hepatology ,biology ,business.industry ,Gastroenterology ,Helicobacter pylori ,biology.organism_classification ,Internal medicine ,medicine ,business ,Omeprazole ,Curing (chemistry) ,medicine.drug - Published
- 1995
- Full Text
- View/download PDF
21. Muscle respiration during exercise
- Author
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A C, Bylund-Fellenius, J P, Idström, and S, Holm
- Subjects
Male ,Oxygen Consumption ,Muscles ,Physical Exertion ,Animals ,Humans ,Intermittent Claudication ,Middle Aged ,Energy Metabolism ,Aged ,Muscle Contraction ,Rats - Abstract
The importance of oxygen as a limiting factor for the mitochondrial respiration in contracting skeletal muscle was studied. The oxygen tension was found to decrease in human gastrocnemius muscle during leg exercise, and the magnitude of the decrease was a function of the intensity as well as the frequency of the muscle contractions. Significant relationships were found between the intramuscular oxygen tension and various muscle metabolites such as the [phosphocreatine], the [ATP]/[ADP] ratio, and the [lactate]/[pyruvate] ratio. This suggests that the oxygen tension measured in the extracellular compartment is of importance for the intracellular energy, and redox state, in exercising muscle. These findings were confirmed in an experimental model where the oxygen delivery could be varied in a more predictable way. Thus, perfusing the contracting rat hindlimb at various oxygen partial pressures showed significant relationships between the oxygen delivery and the [phosphocreatine] and the [lactate] in the gastrocnemius muscle, respectively.
- Published
- 1984
22. Energy metabolism in relation to oxygen supply in contracting rat skeletal muscle
- Author
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J P, Idström, V H, Subramanian, B, Chance, T, Scherstén, and A C, Bylund-Fellenius
- Subjects
Magnetic Resonance Spectroscopy ,Phosphocreatine ,Muscles ,Rats, Inbred Strains ,Phosphates ,Rats ,Oxygen ,Adenosine Triphosphate ,Glucose ,Oxygen Consumption ,Lactates ,Animals ,Female ,Lactic Acid ,Energy Metabolism ,Muscle Contraction - Abstract
The regulation of the energy metabolism in contracting skeletal muscle is under close control, and several regulating factors have been reported. The aim of this study was to investigate the importance of the oxygen supply as a limiting factor for muscle performance during contractions and recovery from contractions. To perform well-controlled standardized experiments on contracting skeletal muscle, the perfused rat hind limb model was developed. The 31P NMR technique was adapted to the rat hind limb model. This enabled continuous nondestructive monitoring of the energy state at various levels of muscular activity. Significant correlations were found between oxygen delivery and oxygen consumption, lactate release, and glucose uptake, respectively. An increased degree of fatigue was observed at lower oxygen deliveries. In both soleus and gastrocnemius muscles, oxygen delivery correlated with the intramuscular concentrations of phosphocreatine (PCr), lactate, and glycogen. The 31P NMR experiments showed a correlation between oxygen delivery and the steady-state level of PCr/inorganic phosphate (Pi) during the contraction period. The rate of recovery in PCr/Pi after the contraction was also dependent on oxygen delivery. The results demonstrate a causal relationship between oxygen supply and energy state in contracting as well as recovering skeletal muscles.
- Published
- 1986
23. [Fibromyalgia--a new name for a syndrome with diffuse muscular disorders]
- Author
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A, Bjelle, A, Bengtsson, K G, Henriksson, J P, Idström, E, Torebjörk, and L E, Thornell
- Subjects
Diagnosis, Differential ,Fibromyalgia ,Terminology as Topic ,Humans - Abstract
This new name for an old and common disease has introduced fresh criteria and initiated clinical and basic research. The present clinical knowledge of the diagnosis and treatment is reviewed. Morphological and biochemical findings in the muscle of fibromyalgia patients have shown an unevenly distributed reduction of the oxygen tension. Hypoxia in the muscle sensitizes nociceptors, resulting in hyperalgesia with a diffuse distribution of pain symptoms. These are difficult for the individual to localize and are often combined with muscle stiffness and increased fatigability. These symptoms correspond to complaints received from fibromyalgia patients.
- Published
- 1989
24. Metabolic adaptation in response to intermittent hypoxia in rat skeletal muscles
- Author
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A, Elander, J P, Idström, S, Holm, T, Scherstén, and A C, Bylund-Fellenius
- Subjects
Oxygen Consumption ,Regional Blood Flow ,Muscles ,Animals ,Female ,Rats, Inbred Strains ,Hypoxia ,Adaptation, Physiological ,Electric Stimulation ,Rats - Published
- 1984
25. Biochemical and 31P-NMR studies of the energy metabolism in relation to oxygen supply in rat skeletal muscle during exercise
- Author
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J P, Idström, V H, Subramanian, B, Chance, T, Scherstén, and A C, Bylund-Fellenius
- Subjects
Magnetic Resonance Spectroscopy ,Oxygen Consumption ,Regional Blood Flow ,Muscles ,Physical Exertion ,Animals ,Phosphorus Isotopes ,Creatine ,Energy Metabolism ,Hindlimb ,Muscle Contraction ,Phosphates ,Rats - Published
- 1984
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