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L Tessieri

Publications and source records attributed to L Tessieri.

7 recordsLinked to original sources
PubMed2000

Effect of Helicobacter pylori eradication on 24-hour gastric pH and duodenal gastric metaplasia.

Published data on the regression of the extent of duodenal gastric metaplasia (DGM) after the eradication of Helicobacter pylori infection and the normalization of the organism-induced alterations in gastric physiology are scanty and controversial. Therefore, we decided to assess the circadian pattern of gastric acidity and the degree of DGM before and one year after H. pylori eradication in a group of duodenal ulcer patients. Fifteen consecutive H. pylori-positive patients with endoscopically proven duodenal ulcer were recruited for this study. The diagnosis of H. pylori infection was based on CLO-test and histology, and DGM was assessed on four bulb biopsies taken before and one year after H. pylori eradication. At the same time, gastric pH was measured by 24-hr continuous intraluminal recording. H. pylori eradication was ascertained by means of concomitant negative CLO-test and histology performed both four weeks after the end of the eradicating treatment and at the one-year endoscopic control. After successful cure, all patients discontinued any antiulcer medication. The mean 24-hr gastric pH was 1.7 +/- 0.4 before and 1.6 +/- 0.4 after one year of H. pylori eradication (P = 0.75). DGM improved in three cases, worsened in four cases, and was unchanged in eight cases at the one-year control (P = 0.87). No correlation was found between 24-hr gastric pH and DGM (P = NS) both at baseline and one year after eradication. Our results show that neither circadian gastric acidity nor DGM change significantly one year after H. pylori eradication in duodenal ulcer patients. Thus, the disappearance of H. pylori infection does not determine any increase in gastric pH and any reversal of gastric-type epithelium in the duodenum.

Adult↗
PubMed2000

Isotope ratio mass spectrometry (IRMS) versus laser-assisted ratio analyzer (LARA): a comparative study using two doses of.

This study was carried out to compare the measurements and the diagnostic accuracy of the traditional expensive IRMS and the new economical LARA system using two doses of [13C]urea + two different test meals in patients undergoing upper gastrointestinal endoscopy, both before and after anti-Helicobacter treatment. A total of 354 dyspeptic patients underwent endoscopy with gastric biopsies to diagnose H. pylori infection by CLO-test and histology. No patients had taken antibiotics, bismuth, or antisecretory drugs in the 4 weeks before testing. After overnight fasting, breath samples were collected simultaneously in both plastic and glass tubes at baseline and at 30 and 60 min after urea ingestion. In 237 patients 100 mg [13C]urea + Ensure and in 117 patients 75 mg [13C]urea + citric acid were given. The test was also performed with the two urea dosages and meals in 67 and 64 infected patients, respectively, four weeks after anti-Helicobacter therapy. H. pylori was considered eradicated when both biopsy-based tests were negative. A delta value >5 per thousand was considered positive. Breath samples with insufficient CO2 levels at both 30 and 60 min were excluded from final analysis (N = 37 in pre- and N = 8 in posttreatment). There was excellent agreement between overall delta values of the two machines with both [13C]urea 100 mg + Ensure and [13C]urea 75 mg + citric acid. The 95% CI of the difference against the mean was wider with the former (mean -1.3, +6.3, and -9.4) than with the latter urea dosage and test meal (mean -1.2, +5.2 and -8.1). LARA and IRMS were equally effective (P = NS) in distinguishing infected from uninfected patients before therapy using both doses of [13C]urea and test meals (sensitivity ranged from 95% to 99% and specificity from 95% to 97%). This good performance was maintained in the posttreatment phase (sensitivity ranged from 90% to 100% and specificity from 90% to 97%), without any statistical difference among the various combinations (P = NS). The LARA system is a valid alternative to IRMS in the diagnosis of H. pylori infection. Both machines provide highly reliable results after 30 min, so that the 60 min sample can be avoided. The dose of 75 mg + citric acid suffices to ensure an accurate UBT. The test performed with both devices and [13C]urea dosages is very effective also for posttherapy evaluation of H. pylori status.

Adult↗
PubMed2000

The impact of antibiotic resistance on the efficacy of three 7-day regimens against Helicobacter pylori.

BACKGROUND: Antibiotic resistance affects the success of anti-Helicobacter pylori therapies and varies greatly from country to country. AIM: To compare the efficacy of three short-term triple regimens in relation to H. pylori primary resistance in our region. METHODS: We enrolled 210 H. pylori-positive dyspeptic patients for this randomized, open, parallel-group study. Three arms of 70 patients each received the following 1-week regimens: (1) ranitidine bismuth citrate 400 mg b.d. + clarithromycin 250 mg b.d. + metronidazole 500 mg b.d. (RCM); (2) bismuth subcitrate 240 mg b.d. + amoxycillin 1000 mg b.d. + metronidazole 500 mg b.d. (BAM); (3) omeprazole 20 mg o.d. + clarithromycin 250 mg b.d. + metronidazole 500 mg b.d. (OCM). H. pylori was assessed by CLO-test and histology before and 4 weeks after therapy. Antibiotic resistance was assessed by E-test. RESULTS: On intention-to-treat analysis RCM was more effective than OCM (84% vs. 69%; P < 0.03) and BAM (84% vs. 63%; P < 0.004). MIC determination was successful in 117 out of 210 patients (55%); metronidazole resistance was present in 52 out of 117 patients (44%) and clarithromycin resistance was present in 17 out of 117 patients (14%). Excellent cure rates were achieved when strains were sensitive to both antibiotics (100% with RCM and BAM and 90% with OCM), whereas RCM was superior to OCM (P=0.009) and BAM (P=0.001) with respect to overall resistant strains (94% vs. 57% and 38%, respectively). CONCLUSIONS: One-week RCM is the best regimen to eradicate H. pylori in our geographical area. This seems to be linked to the better ability of RCM compared to OCM and BAM in overcoming the high prevalence of H. pylori resistance to both metronidazole and clarithromycin in our region.

Adult↗
PubMed2000

Anderson localization as a parametric instability of the linear kicked oscillator

We rigorously analyze the correspondence between the one-dimensional standard Anderson model and a related classical system, the "kicked oscillator" with noisy frequency. We show that the Anderson localization corresponds to a parametric instability of the oscillator, the localization length being related to the rate of exponential growth of the energy of the oscillator. Analytical expression for a weak disorder is obtained, which is valid both inside the energy band and at the band edge.

Journal Article↗
PubMed2000

[Can Helicobacter pylori infection be a risk factor for the severity of rheumatoid arthritis?].

AIM: In this study we assessed the effect of Helicobacter pylori eradication in patients with established rheumatoid arthritis (RA) in order to show a possible pathogenetic role of the infection in this disease. METHODS: We recruited 31 patients with variable RA activity. Of them, 15 were Hp-positive (12 F and 3 M, mean age 55 +/- 10.6 years) and 16 Hp-negative (13 F and 3 M, mean age 54.2 +/- 9.1 years) on the basis of the concomitant positive or negative findings of both CLO-test and histology performed on both antral and corpus biopsies. The infected group was treated and the bacterium was considered eradicated when both tests were negative a month after therapy. We have evaluated the disease activity at baseline and during a total follow-up period of 16 months with check-points every 4-months and compared clinical and laboratory findings between the Hp-negative and the eradicated groups. Both groups were being treated with NSAIDs and prednisolone (< or = 7.5 mg/die) or its equivalents. RESULTS: Hp-eradicated RA patients showed a progressive improvement overtime (p = 0.0009) of all clinical indices compared with baseline, while Hp-negative RA patients did not. At the 16-month checkpoint, the eradicated RA patients differed significantly (p < 0.006) from patients without Hp infection by all indices, except grip strength of the hands. Also all laboratory data improved significantly from baseline to the 16 month checkpoint (p < 0.03) within the Hp-eradicated group and between the two groups of eradicated and Hp-negative RA patients (p < 0.0007) except for Hb, aCL IgM and gamma-globulins. CONCLUSIONS: Our data suggest that Hp infection is implicated in the pathogenesis of RA. On the basis of our data, the eradication of Hp should be recommended in infected RA patients.

Aged↗