0000000000337280

AUTHOR

Maria Raffaella Mele

showing 15 related works from this author

Comparison of isotope ratio mass spectrometry and nondispersive isotope-selective infrared spectroscopy for 13C-urea breath test.

1999

The 13C-urea breath test (UBT) is a sensitive and noninvasive method to diagnose Helicobacter pylori infection, but mass spectrometry (IRMS) is very expensive. The aims of this study were to compare the new low-priced infrared spectroscopy with IRMS in detecting the infection and to assess the influence of feeding on test accuracy.One hundred thirty-four patients with dyspeptic symptoms were recruited. Of these, 74 were infected and 60 uninfected on the basis of both CLO-test and histology. A subgroup of 37 patients (22 H. pylori-positive and 15 H. pylori-negative) was studied under fasting and nonfasting conditions on two different days. Duplicate breath samples were analyzed with two IRMS…

MalePathologymedicine.medical_specialtySpectrophotometry InfraredAnalytical chemistryInfrared spectroscopyMass spectrometrySensitivity and SpecificityMass Spectrometry13C urea breath testHelicobacter Infectionschemistry.chemical_compoundmedicineHumansUreaIsotope-ratio mass spectrometryDyspepsiaBreath testCarbon IsotopesHepatologymedicine.diagnostic_testIsotopeHelicobacter pyloribusiness.industryGastroenterologyMiddle AgedchemistryBreath TestsDuodenal UlcerUreaFemalebusiness
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Negative Effect of Ranitidine on The Results of Urea Breath Test for The Diagnosis of Helicobacter Pylori

2001

In analogy with proton pump inhibitors, H2-antagonists may also be responsible for false-negative results on urea breath test for the detection of Helicobacter pylori. In this study we assessed the frequency and duration of false-negative urea breath tests in patients given different doses of ranitidine.A total of 120 consecutive dyspeptic patients infected with H. pylori on the basis of concomitant positive results of CLO-test, histology and urea breath test were recruited for this prospective, open, parallel-group study performed in an urban university gastroenterological clinic. They were randomized to receive an acute treatment with either ranitidine 300 mg once a day in the evening, ra…

Malemedicine.medical_specialtyTime FactorsUrea breath testSpirillaceaeRanitidineGastroenterologyHelicobacter InfectionsRanitidinechemistry.chemical_compoundInternal medicinemedicineHumansUreaProspective StudiesDyspepsiaFalse Negative ReactionsBreath testCarbon IsotopesDose-Response Relationship DrugHelicobacter pyloriHepatologymedicine.diagnostic_testbiologybusiness.industrydigestive oral and skin physiologyFalse Negative ReactionsGastroenterologyMiddle AgedHelicobacter pyloribacterial infections and mycosesHelicobacter Infectionsbiology.organism_classificationBreath TestsHistamine H2 AntagonistschemistryUreaFemalebusinessmedicine.drugAmerican Journal of Gastroenterology
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Head-to-head comparison of 1-week triple regimens combining ranitidine or omeprazole with two antibiotics to eradicate Helicobacter pylori

1999

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…

medicine.medical_specialtyHepatologybiologymedicine.drug_classbusiness.industrySpirillaceaeAntibioticsGastroenterologyProton-pump inhibitorHelicobacter pyloribiology.organism_classificationGastroenterologySurgeryRanitidineClarithromycinInternal medicinemedicinePharmacology (medical)businessOmeprazolemedicine.drugAntibacterial agentAlimentary Pharmacology & Therapeutics
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Optimal duration of therapy combining ranitidine bismuth citrate with clarithromycin and metronidazole in the eradication of Helicobacter pylori infe…

1999

Background: Ranitidine bismuth citrate (RBC) co-prescribed with clarithromycin and metronidazole for 1 week has been shown to be an effective eradicating regimen for Helicobacter pylori. Aim: To determine the optimal duration of this regimen. Methods: A series of 165 dyspeptic patients were recruited for this randomized, open, parallel-group study. They were subdivided into three groups receiving RBC 400 mg b.d. plus clarithromycin 250 mg b.d. and metronidazole 500 mg b.d. for three different periods (4, 7 and 10 days). H. pylori infection was assessed by the concomitant positivity of CLO-test and histology performed at the pre-entry endoscopy. The bacterium was considered eradicated on the…

Breath testmedicine.medical_specialtyIntention-to-treat analysisHepatologymedicine.diagnostic_testbiologybusiness.industryGastroenterologyHelicobacter pyloribiology.organism_classificationGastroenterologySurgeryRanitidineMetronidazoleRegimenInternal medicineClarithromycinmedicinePharmacology (medical)businessAntibacterial agentmedicine.drugAlimentary Pharmacology & Therapeutics
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Stool antigen assay (HpSA) is less reliable than urea breath test for post-treatment diagnosis of Helicobacter pylori infection

2002

Summary Background : The diagnostic yield of the stool antigen test (HpSA) in evaluating the results of Helicobacter pylori eradication therapy is controversial, but many studies have used only the 13C-urea breath test (13C-UBT) as a gold standard which has greatly reduced their relevance. Aim : To compare the reliability of HpSA and 13C-UBT in patients post-treatment using biopsy-based methods as reference tests. Methods : A total of 100 consecutive dyspeptic patients (42 male and 58 female; mean age, 56 ± 18 years) were enrolled in our study. All patients were H. pylori positive on the basis of at least two biopsy-based methods, and underwent 1 week of treatment with various triple therap…

Breath testmedicine.medical_specialtyHepatologymedicine.diagnostic_testbiologybusiness.industryUrea breath testGastroenterologyRapid urease testGold standard (test)Helicobacter pyloribiology.organism_classificationGastroenterologySurgeryPredictive value of testsInternal medicineBiopsymedicinePharmacology (medical)businessAntibacterial agentAlimentary Pharmacology & Therapeutics
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Evaluation of 24-hour gastric acidity in patients with hepatic cirrhosis.

1996

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…

AdultLiver CirrhosisMalemedicine.medical_specialtyCirrhosisGastroenterologyGastric AcidReference ValuesInternal medicinemedicineHumansCircadian rhythmProspective StudiesProspective cohort studyAntrumParietal cellAgedHepatologybiologybusiness.industryStomachdigestive oral and skin physiologyHelicobacter pyloriHydrogen-Ion ConcentrationMiddle Agedmedicine.diseasebiology.organism_classificationCircadian Rhythmmedicine.anatomical_structureGastric MucosaGastric acidFemalebusiness
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Helicobacter pyloriinfection is not involved in the pathogenesis of either erosive or non-erosive gastro-oesophageal reflux disease

2003

Summary Background : The majority of reflux patients have non-erosive reflux disease. Aim : To evaluate the influence of Helicobacter pylori on oesophageal acid exposure in patients with both non-erosive and erosive reflux disease and in a group of controls. The pattern and distribution of chronic gastritis were also assessed. Methods : One hundred and twelve consecutive patients with symptoms of gastro-oesophageal reflux disease agreed to undergo both upper gastrointestinal endoscopy and 24-h oesophageal pH-metry. Patients were grouped as H. pylori-positive or H. pylori-negative on the basis of both CLO-test and histology, and as cases with or without oesophagitis on the basis of endoscopy…

medicine.medical_specialtyHepatologybiologyEsophageal diseasebusiness.industrySpirillaceaeGastroenterologyRefluxChronic gastritisHelicobacter pyloribiology.organism_classificationmedicine.diseaseGastroenterologymedicine.anatomical_structureInternal medicinemedicinePharmacology (medical)EsophagusGastritismedicine.symptombusinessAntrumAlimentary Pharmacology & Therapeutics
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Comparison of the main oesophageal pathophysiological characteristics between short- and long-segment Barrett's oesophagus

2002

Aim: To assess the oesophageal manometric characteristics and 24-h pH profiles of patients with both short-segment and long-segment Barrett's oesophagus and compare them with those of patients with reflux oesophagitis and controls. Methods: Seventy-nine patients who had undergone upper digestive endoscopy were recruited: 16 had short-segment Barrett's oesophagus, 13 had long-segment Barrett's oesophagus, 25 had grade III oesophagitis according to the Savary–Miller classification and 25 were used as controls. The diagnosis of Barrett's oesophagus was based on the histological detection of specialized intestinal metaplasia, which extended  3 cm in patients with long-segment disease. All subje…

medicine.medical_specialtyHepatologybusiness.industryEsophageal diseasedigestive oral and skin physiologyGastroenterologyCase-control studyRefluxIntestinal metaplasiaLong segmentmedicine.diseasedigestive systemGastroenterologydigestive system diseasesPathophysiologymedicine.anatomical_structureInternal medicineotorhinolaryngologic diseasesmedicinePharmacology (medical)EsophagusbusinessEsophagitisAlimentary Pharmacology & Therapeutics
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A new 1-week therapy for Helicobacter pylori eradication: rani- tidine bismuth citrate plus two antibiotics

1997

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…

Malemedicine.medical_specialtyRanitidineGastroenterologyGroup BHelicobacter InfectionsRanitidineClarithromycinMetronidazoleClarithromycinInternal medicinePyloric AntrummedicineHumansPharmacology (medical)Antibacterial agentHelicobacter pyloriHepatologybiologybusiness.industryGastroenterologyHelicobacter pyloribiology.organism_classificationAnti-Bacterial AgentsSurgeryMetronidazoleRegimenHistamine H2 AntagonistsRanitidine HydrochlorideDrug Therapy CombinationFemalebusinessBismuthmedicine.drugAlimentary Pharmacology and Therapeutics
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Effect of gastric acid suppression on 13 C-urea breath test: comparison of ranitidine with omeprazole

2000

Background: The assessment of the effect of H2 antagonists on the results of the urea breath test has produced controversial results. Aim: To assess whether standard doses of both omeprazole and H2 blockers can adversely influence the accuracy of the urea breath test. Methods: Sixty dyspeptic patients with ascertained Helicobacter pylori infection were recruited for this prospective, open study. They were randomized to receive either omeprazole 20 mg at 08:00 hours (n = 30) or ranitidine 300 mg at 22:00 hours (n = 30) for 14 days. The urea breath test was performed at baseline, on day 14, while patients were still taking the antisecretory drugs, and on day 21, 1 week after their cessation. …

Breath testmedicine.medical_specialtyHepatologybiologymedicine.diagnostic_testbusiness.industrymedicine.drug_classUrea breath testGastroenterologyProton-pump inhibitorHelicobacter pyloribiology.organism_classificationGastroenterologySurgeryRanitidineInternal medicineMedicineIngestionPharmacology (medical)businessAdverse effectOmeprazolemedicine.drugAlimentary Pharmacology & Therapeutics
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Circadian pattern of intragastric acidity in patients with non-erosive reflux disease (NERD)

2003

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%) …

Breath testmedicine.medical_specialtyHepatologybiologymedicine.diagnostic_testbusiness.industryNerdEsophageal diseaseSpirillaceaeStomachdigestive oral and skin physiologyGastroenterologyRefluxHelicobacter pyloribiology.organism_classificationmedicine.diseaseGastroenterologydigestive system diseasesmedicine.anatomical_structureInternal medicinemedicinePharmacology (medical)businessEsophagitisAlimentary Pharmacology & Therapeutics
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Variability in individual response to various doses of omeprazole. Implications for antiulcer therapy.

1994

This study was carried out in order to perform a combined prospective assessment of the individual pharmacodynamic response and of duodenal ulcer healing in patients treated with three different doses of omeprazole. Ninety-nine patients with endoscopically proven duodenal ulcers were subdivided into three parallel groups of 33 cases, who were randomly assigned to receive orally at 0800 hr, in single blind fashion, either 10 mg, 20 mg, or 40 mg of omeprazole. All of them underwent continuous intragastric pH monitoring both in basal conditions and on the fifth day of each dose regimen; ulcer healing was then assessed endoscopically after four weeks of treatment. All three doses of omeprazole …

Malemedicine.medical_specialtyTime FactorsPhysiologymedicine.medical_treatmentGastroenterologyGastric AcidBasal (phylogenetics)PharmacokineticsInternal medicineMedicineHumansSingle-Blind MethodOmeprazoleMonitoring PhysiologicChemotherapyWound HealingDose-Response Relationship Drugbusiness.industryGastroenterologyHepatologyHydrogen-Ion ConcentrationMiddle AgedRegimenmedicine.anatomical_structurePharmacodynamicsDuodenal UlcerDuodenumFemalebusinessIon-Selective ElectrodesOmeprazolemedicine.drugDigestive diseases and sciences
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Time pattern of gastric acidity in Barrett's esophagus.

1996

Increased gastroesophageal acid reflux is frequently found in patients with Barrett's esophagus, and it has been hypothesized that gastric acid hypersecretion could be an important factor aggravating the exposure of esophageal mucosa to acid and then contributing to the development of this disorder. The aim of the present study was to assess whether the circadian pattern of gastric acidity differs between refluxer patients with and without Barrett's esophagus and normal subjects. Continuous 24-hr gastric pH monitoring was performed in 119 healthy volunteers, 20 patients with Barrett's esophagus, 37 patients with moderate and 10 patients with severe reflux esophagitis without Barrett's esoph…

Malemedicine.medical_specialtyPhysiologyPopulationGastroenterologyGastric AcidBarrett EsophagusInternal medicinemedicineHumansEsophagusReflux esophagitiseducationEsophagitis PepticMonitoring Physiologiceducation.field_of_studybusiness.industryEsophageal diseaseStomachdigestive oral and skin physiologyGastroenterologyRefluxGastric Acidity DeterminationMiddle Agedmedicine.diseasedigestive system diseasesCircadian Rhythmmedicine.anatomical_structureBarrett's esophagusGastric acidFemalebusinessDigestive diseases and sciences
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Circadian gastric acidity in Helicobacter pylori positive ulcer patients with and without gastric metaplasia in the duodenum.

1996

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…

AdultMalemedicine.medical_specialtyDuodenumSpirillaceaeGastroenterologyEpitheliumHelicobacter InfectionsGastric AcidInternal medicineMetaplasiaBiopsymedicineHumansAntrumMonitoring PhysiologicAnalysis of VarianceMetaplasiabiologymedicine.diagnostic_testHelicobacter pyloribusiness.industrydigestive oral and skin physiologyStomachGastroenterologyHistologyHelicobacter pyloriHydrogen-Ion ConcentrationMiddle Agedbiology.organism_classificationdigestive system diseasesCircadian Rhythmmedicine.anatomical_structureGastric MucosaDuodenal UlcerDuodenumFemaleGastritismedicine.symptombusinessResearch Article
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The effects of omeprazole 20 and 40 mg twice daily on intragastric acidity in duodenal ulcer patients.

1996

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…

AdultMalemedicine.medical_specialtymedicine.drug_classProton-pump inhibitorGastroenterologyHelicobacter InfectionsGastric AcidInternal medicineClarithromycinmedicineHumansSingle-Blind MethodPharmacology (medical)Enzyme InhibitorsOmeprazoleGastric Acidity DeterminationCross-Over StudiesHelicobacter pyloriHepatologybiologybusiness.industryStomachGastroenterologyProton Pump InhibitorsGastric Acidity DeterminationMiddle AgedHelicobacter pyloribiology.organism_classificationCrossover studyCircadian Rhythmmedicine.anatomical_structureDuodenal UlcerDuodenumFemalebusinessOmeprazolemedicine.drugAlimentary Pharmacology & Therapeutics
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