Biomedical subjects

A Pastorelli

Publications and source records attributed to A Pastorelli.

6 recordsLinked to original sources

PubMed2001

Helicobacter pylori CagA-positive strains affect oxygen free radicals generation by gastric mucosa.

BACKGROUND: Helicobacter pylori plays a key role in production of reactive oxygen metabolites (ROMs). However, the importance of virulent CagA-positive H. pylori strains remains to be determined. The aim of this study was to assess ROMs production in gastric biopsies of patients infected by H. pylori. Results were correlated to CagA status and acute inflammatory infiltration. METHODS: Patients undergoing gastroscopy were enrolled. H. pylori infection was assessed by histology and 13C urea breath test. CagA status was assessed through serology. ROMs were assayed in gastric biopsies by luminol-enhanced chemiluminescence (CLS). Gastric mucosal inflammation was histologically graded and neutrophils were individually counted. Macroscopical damage was scored according to a modified Lanza score. RESULTS: 40 out of 60 patients evaluated were H. pylori (HP) positive. Of the 40 infected patients, 24 were CagA-positive. CLS emission was significantly higher in HP-CagA-positive patients than in HP-CagA-negatives and uninfected. ROMs production showed a significant correlation to neutrophil infiltrate in all groups. CONCLUSIONS: Gastric mucosa of patients infected by HP-CagA-positive strains is characterized by a higher generation of ROMs and by greater neutrophil counts than that observed in HP-CagA-negative subjects. Since ROMs production is associated with DNA oxidative damage, a long-term stimulation by these strains might be relevant in the pathogenesis of gastric malignancies. Assessment of CagA status might be useful to discriminate patients in which H. pylori eradication is advisable.

Antigens, Bacterial↗

PubMed2000

Five-day regimens containing ranitidine bismuth citrate plus high-dose clarithromycin and either amoxycillin or tinidazole for Helicobacter pylori infection.

BACKGROUND: Ranitidine bismuth citrate (RBC)-based triple therapies for a period of 7 days have proved to be an effective treatment for Helicobacter pylori. AIM: To investigate the eradication efficacy, safety profile and patient compliance of two RBC-based triple therapies given for 5 days. METHODS: Eighty H. pylori-positive patients with dyspeptic symptoms, referred to us for gastroscopy, were consecutively enrolled in this prospective, randomized, open-label study. These patients were randomly assigned to receive a 5-day course of RBC 400 mg b.d. plus clarithromycin 500 mg b.d. and either tinidazole 500 mg b.d. (RBCCT group) or amoxycillin 1 g b.d. (RBCCA group). The H. pylori status was assessed by means of histology and rapid urease test at entry, and by 13C-urea breath test 8 weeks after the completion of treatment. RESULTS: All enrolled patients completed the study. Thirty-seven of 40 patients treated with RBCCT (both PP and ITT analysis: 93%; 95% CI: 80-98%) and 35 of 40 in the RBCCA group (both PP and ITT analysis: 88%; 95% CI: 73-96%) returned H. pylori-negative. Slight or mild side-effects occurred in 4/40 patients (10%) in the RBCCT group and in 5/40 (12%) in the RBCCA group. CONCLUSIONS: This is the first study demonstrating the efficacy of RBC-based triple therapies given for only 5 days. RBC regimens containing high-dose clarithromycin and either amoxycillin or tinidazole prove to be well tolerated, safe and preserve good eradication rates even when administered for a shorter than conventional duration.

Amoxicillin↗

PubMed2000

Efficacy of a multistep strategy for Helicobacter pylori eradication.

BACKGROUND: Helicobacter pylori eradication therapies do not achieve 100% success rates. Antibiotic resistant strains are among the major causes of failure. Current recommendations concerning the management of treatment failures are not fully clear. AIM: To evaluate the efficacy of a multi-step therapeutic strategy in a large group of infected patients. METHODS: A total of 2606 H. pylori-positive patients were administered tinidazole, clarithromycin and a proton pump inhibitor for 1 week. Patients with continuing infection were then given a second 1-week course of amoxycillin, clarithromycin and ranitidine bismuth citrate. Patients still infected after the second course underwent upper gastrointestinal endoscopy with H. pylori culture, and then received a 1-week quadruple proton pump inhibitor-bismuth based scheme established on H. pylori antibiotic sensitivity. RESULTS: After the first step, eradication was achieved in 2063 out of 2413 patients [86% per protocol analysis (PP); 79% intention-to-treat analysis (ITT)]. First-step failures (350 out of 2413; 14.5% PP) showed second-step eradication rates of 82% (271 out of 329 patients, PP; 77% ITT). The specific quadruple therapy for second-step failures (58 out of 329, 18% PP) achieved 77% (30 out of 39 patients, PP) or 52% (ITT) success. This algorithm led to overall eradication rates of 99% (PP) or 91% (ITT). CONCLUSIONS: This multi-step strategy succeeded in a high percentage of H. pylori infected patients. Given the lack of precise guidelines on treatment failures, assessing H. pylori sensitivity to antibiotics only after failure of the second treatment could be suggested in clinical practice.

Algorithms↗

PubMed1999

Six-day or seven-day regimens with ranitidine bismuth citrate plus high-dose clarithromycin and tinidazole are both effective against Helicobacter pylori infection.

We compared the efficacy of two therapies to eradicate H. pylori infection including ranitidine bismuth citrate (400 mg twice daily), clarithromycin (500 mg twice daily), and tinidazole (500 mg twice daily), administered for six or seven days. Eighty H. pylori-positive patients were consecutively recruited and randomly subdivided into groups A and B, receiving one of the two treatment regimens. The H. pylori status was evaluated by means of histology and rapid urease test at entry, and by [13C]urea breath test alone eight weeks after treatment. All 40 patients in group A and 39/40 in group B completed the study. Thirty-six of 40 patients in the group A (90%) and 36 of 39 in the group B (92%) became H. pylori-negative. Slight or mild side-effects occurred in 4/40 patients (10%) of group A and in 5/39 (13%) of group B. In conclusion, both regimens we tested yielded high eradication rates with modest side effects. This is the first trial investigating a triple-drug RBC-based regimen administered for only six days.

Adolescent↗

PubMed1999

Hepatic stellate cell activation and liver fibrosis are associated with necroinflammatory injury and Th1-like response in chronic hepatitis C.

BACKGROUND/AIMS: The involvement of a direct viral cytopathic effect or an immune-mediated mechanism in the progression of hepatic damage in chronic hepatitis C is controversial. The type of immune response is itself a matter of controversy, and histological data are lacking. The aim of this study was to identify the factors associated with the progression of liver injury in 30 HCV/RNA-positive untreated patients with chronic hepatitis. METHODS: Necroinflammatory and architectural damage were evaluated using Ishak's score. Activated hepatic stellate cells (HSC) were visualized by immunohistochemistry for alpha-smooth muscle actin (alphaSMA) and quantitated by morphometry. Plasma HCV/RNA was evaluated using a competitive RT-PCR method. To study the type of immune response involved in the progression of liver injury, interferon gamma (IFNgamma)-positive cells (as expression of a Th1-like response) were evaluated by immunohistochemistry and quantitated by morphometry. RESULTS: HSC were mostly detected close to areas of lobular necroinflammation or lining fibrotic septa. The alphaSMA- and Sirius Red-positive parenchyma correlated significantly with necroinflammatory and architectural scores. IFNgamma-positive cells were detected in periportal areas associated with the inflammatory infiltrates and significantly correlated with architectural damage. No relationship was found between the histological features of liver injury and viral load. CONCLUSIONS: HSC activation and progression of liver injury are unrelated to viral load but associated with a Th1-like response, a plausible target for the treatment of chronic hepatitis C.

Actins↗

PubMedDate not supplied

[Reconversion after Hartmann's procedure. Our experience].

An increasing number of intestinal reconversion after Hartmann have been performed in recent years, especially due to improved surgical techniques and progressively lengthened lifespan. The authors report 33 cases of intestinal recanalization of 100 interventions according to Hartmann from 1984 to 1996 (21 not neoplastic pathologies, 12 neoplasias). The variables considered included: patient age, type of disease requiring intervention according to Hartmann, oncologic characteristic of patients with neoplasia, interval between the two interventions, preoperative examinations performed, morbidity and mortality after reconversion. Furthermore, the fundamental indications for reconversion are described, in particular in patients with neoplasias (CEA, transanal echo, total body Ct, anal manometry). The low frequency of preoperative complications, zero mortality, satisfactory long-term follow-up (only one patient with neoplastic relapse) indicate that colon-rectal reconversion can also be performed in the elderly and patients with neoplasias with favorable prognosis.

Aged↗