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Mario Rizzetto

Publications and source records attributed to Mario Rizzetto.

At least 19 recordsLinked to original sources
PubMed2007

Pancreatic cancer imaging: the new role of endoscopic ultrasound.

Pancreatic cancer is the most deadly of all gastrointestinal malignancies and has a very poor prognosis. Unfortunately, most patients present late in the course of their disease and, at the time of diagnosis, only 10 to 25% of patients will be eligible for potentially curative resection. Efforts must be oriented towards an early diagnosis and towards reliably identifying patients who can really benefit from major surgery. A suspected pancreatic tumor can be a difficult challenge for the clinician. In the last ten years, we have witnessed notable technological improvements in radiological and nuclear imaging. Taking this into account, we will try to delineate the new role of endoscopic ultrasound (EUS) in pancreatic tumor imaging and to place EUS in a shareable diagnostic and staging algorithm. To date, the most accurate imaging techniques for pancreatic neoplasms remain contrast-enhanced computed tomography and EUS. EUS has the highest accuracy in detecting small lesions, in assessing tumor size and lymph node involvement, but helical CT must still be the first choice in patients with a suspected pancreatic tumor. However, after this first step, there is a place for EUS as a second diagnostic level in several cases: negative results on CT scan and persistent strong clinical suspicion of pancreatic cancer, doubtful results on CT scans or the need for cytohistological confirmation. In the near future, there will be great opportunities for the development of diagnostic and therapeutic EUS and pancreatic cancer could be the best testing ground.

Biopsy, Fine-Needle↗
PubMed2007

Potential role for the common cystic fibrosis DeltaF508 mutation in Crohn's disease.

BACKGROUND: Inflammatory bowel disease (IBD) is an epithelial barrier disease that is thought to result from a dysregulated interaction with bacteria in the intestine of genetically predisposed individuals. The cystic fibrosis transmembrane conductance regulator (CFTR), which is mutated in the autosomal recessive disease cystic fibrosis, modulates gut permeability, mucus production, and epithelial interactions with bacteria. The cystic fibrosis DeltaF508 mutation is commonly found in the general population and has been shown to result in a reduced number of CFTR molecules at the surface of epithelial cells. Given the important biological functions of CFTR in the intestine, we tested whether this mutation is of relevance to IBD. METHODS: Using DNA heteroduplex analysis, we investigated the distribution of DeltaF508 heterozygosity in 2568 subjects from three independent cohorts of Italian, Swedish, and Scottish IBD patients and controls. RESULTS: In all three cohorts an association between DeltaF508 and Crohn's disease (CD) was observed. Specifically, DeltaF508 heterozygosity was markedly underrepresented in CD patients from Italy and Sweden (P = 0.021 and 0.027 versus controls, respectively), while stratification for disease location revealed an absence of DeltaF508 carriers among Scottish CD patients with right-sided colitis (P = 0.023 versus all other locations). CONCLUSIONS: DeltaF508 heterozygosity might exert a protective effect in CD.

Adolescent↗
PubMed2006

Long-term therapy with adefovir dipivoxil for HBeAg-negative chronic hepatitis B for up to 5 years.

BACKGROUND & AIMS: Treatment with adefovir dipivoxil for 48 weeks resulted in clinical improvement in patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B that was lost when treatment was discontinued. We investigated the efficacy, safety, and resistance profile of adefovir dipivoxil treatment for up to 240 weeks. METHODS: HBeAg-negative patients were treated double blind with placebo or adefovir dipivoxil 10 mg once daily for 48 weeks, followed by adefovir dipivoxil from week 49 to 96. At week 97, 125 patients enrolled in a 144-week, open-label phase. Patients received adefovir dipivoxil for up to 192 or 240 weeks. RESULTS: Serum hepatitis B virus (HBV) DNA levels were less than 1000 copies per milliliter in 67% of patients, and alanine aminotransferase (ALT) levels normalized in 69% after 240 weeks. After 192 or 240 weeks of treatment, over 83% of patients had improvement in necroinflammation, and over 73% had improvement in fibrosis. Ishak fibrosis scores improved compared with baseline in 35%, 55%, and 71% of patients after 48, 192, and 240 weeks of adefovir dipivoxil, respectively. After 240 weeks, the cumulative probability of HBV polymerase mutations was 29%, but the cumulative probability of mutations with virologic resistance was 20% and of mutations, virologic resistance, and ALT elevations was 11%. Slight elevations in creatinine were confirmed in 4 (3%) patients. CONCLUSIONS: Treatment with adefovir dipivoxil for up to 240 weeks was well tolerated and produced significant, increasing improvement in hepatic fibrosis, durable suppression of HBV replication, normalization of liver enzymes, and delayed development of resistance.

Adenine↗
PubMed2006

Long-term follow-up of previous hepatitis C virus positive nonresponders to interferon monotherapy successfully retreated with combination therapy: are they really cured?

OBJECTIVES: To evaluate whether in chronic hepatitis C-positive patients who failed to respond to interferon (IFN) monotherapy a sustained response obtained with retreatment using the combination therapy of IFN + ribavirin can be safely considered to reflect eradication of the infection. METHODS: Prospective follow-up of a cohort of 97 patients who responded to retreatment with different regimens of IFN + ribavirin after failing to respond to a first IFN monotherapy course. The patients were followed throughout 7 yr of follow-up with determinations of HCV viremia every 6 months. RESULTS: At the end of the follow-up, 11 patients (11.3%) showed a viremic reappearance. HCV late relapse rates were 0%, 13%, 20%, and 12% in patients retreated, respectively, with 3 MU IFN + ribavirin for 12 months (Group 1), 5 MU IFN + ribavirin for 12 months (Group 2), 3 MU IFN + ribavirin for 6 months (Group 3), and 5 MU IFN + ribavirin for 6 months (Group 4) (Group 2 vs Group 3, p= 0.005). The virologic relapses occurred within 2 yr from therapy withdrawal. Among patients with genotype 1 and 4, the long-term response was significantly higher in Group 2 than in Group 3 (15%vs 3%, p= 0.03). In patients with genotype 2 and 3, the long-term virological response was not affected by the different regimens. CONCLUSIONS: Nonresponders to IFN monotherapy who achieve a sustained virologic response after retreatment with IFN + ribavirin stand a discrete risk of HCV reactivation within 2 yr after therapy.

Adult↗
PubMed2006

Feasibility and safety of G-CSF administration to induce bone marrow-derived cells mobilization in patients with end stage liver disease.

BACKGROUND/AIMS: To evaluate feasibility, safety and pattern of bone marrow-derived cells (BMC) mobilization in patients with end stage liver cirrhosis following granulocyte-colony stimulating factor (G-CSF) administration. METHODS: Eight patients with severe liver cirrhosis (Child-Pugh score B-C, spleen diameter less than 170 mm) were included. They were treated with G-CSF (5 microg/kg b.i.d for three consecutive days) to mobilize BMC, evaluated as circulating CD34+ve cells (flow cytometry) and myeloid CFU-GM progenitors (in vitro colony growth assay). Co-expression in CD34+ve cells markers of differentiation (Thy1, CD133, CXCR4, c1qRp) were investigated on CD34+ve cells by double direct immunofluorescence. Data from 40 healthy haematopoietic stem cell donors were used as controls. RESULTS: Mobilization of CD34+ve cells occurred in all patients. It was paralleled by expansion of circulating CFU-GM progenitors. Circulating CD34+ve cells co-expressed epithelial and stem cell markers in both cirrhotics and volunteer stem cell donors. G-CSF was well tolerated, no adverse event occurred, a significant reversible increase of splenic longitudinal diameter was observed. CONCLUSIONS: (i) G-CSF mobilization of BMC co-expressing epithelial and stem markers occurred in all cirrhotic patients; (ii) splenomegaly up to 170 mm does not prevent safe BMC mobilization following G-CSF in patients with end stage liver disease; (iii) mobilized BMC may represent an easy immature cell source potentially useful for novel approaches for liver regeneration.

Aged↗
PubMed2006

Pegylated interferon alpha-2b as monotherapy or in combination with ribavirin in chronic hepatitis delta.

Therapy of chronic hepatitis delta with standard interferon therapy has met with limited efficacy. This study was designed to examine the efficacy and safety of peginterferon with or without ribavirin. Thirty-eight serum hepatitis B surface antigen- and HDV RNA-positive patients with alanine aminotransferase (ALT) more than 1.5 times the upper normal limit received peginterferon alpha-2b (1.5 microg/kg) alone as monotherapy (n=16) or in combination with ribavirin (n=22), for 48 weeks. Thereafter, all the patients were maintained on peginterferon for 24 weeks and followed for 24 weeks off therapy. The primary end point studied was the virological and biochemical response at the end of follow-up. HDV RNA was determined by single or nested polymerase chain reaction assays. Twenty-seven patients (71%), 11 receiving monotherapy and 16 receiving the combination treatment, completed the follow-up. At the end of treatment, a virological response was observed in 3 of the patients treated with peginterferon (19%) and in 2 of the patients treated with combination therapy (9%), and a biochemical response was observed in 6 (37.5%) and 9 patients (41%), respectively. In nonresponders, ALT diminished from a mean of 174+/-53 to 86+/-41 IU/L. At the end of follow-up, serum HDV RNA was negative in 8 patients (21%), and a biochemical response was detected in 10 patients (26%). Treatment was discontinued in 25% of the patients, and dosing was modified in 58%. In conclusion, a prolonged course of peginterferon alpha-2b resulted in clearance of serum HDV RNA and ALT normalization in a fifth of patients with chronic hepatitis D, while ribavirin had no effect on the viral clearance rate. Overall tolerance of therapy was poor.

Adult↗
PubMed2006

Fibrosis in genotype 3 chronic hepatitis C and nonalcoholic fatty liver disease: Role of insulin resistance and hepatic steatosis.

Hepatic steatosis has been associated with fibrosis, but it is unknown whether the latter is independent of the etiology of fat infiltration. We analyzed the relationship between clinical characteristics, insulin resistance (HOMA-R) and histological parameters in 132 patients with "viral" steatosis caused by genotype 3 chronic hepatitis C (CHC-3) and 132 patients with "metabolic" steatosis caused by nonalcoholic fatty liver disease (NAFLD), matched by age, BMI, and degree of liver fat accumulation. Tests of liver function were comparable in the two study populations. The prevalence of features of insulin resistance was higher in NAFLD, as was HOMA-R (P = .008). Logistic regression analysis confirmed that steatosis was associated with a high viral load and low serum cholesterol in CHC-3, and with high aminotransferase, glucose, ferritin and hypertriglyceridemia in NAFLD. At univariate analysis, advanced fibrosis was associated with steatosis in NAFLD, but not in CHC-3. Other parameters related to fibrosis severity were HOMA-R and a low platelet count in CHC-3, and high aminotransferases, HOMA-R, ferritin and low HDL-cholesterol in NAFLD. On multivariate analysis, only low platelet count (OR = 0.78; 95% CI, 0.67-0.92) and HOMA-R (OR = 2.98; 1.13-7.89) were independent predictors of advanced fibrosis in CHC-3. In NAFLD, severe fibrosis was predicted by fat grading (OR = 3.03; 1.41-6.53), ferritin (OR = 1.13; 1.03-1.25) and HOMA-R (OR = 1.16; 1.02-1.31). In conclusion, insulin resistance is an independent predictor of advanced fibrosis in both NAFLD and CHC-3, but the extent of steatosis contributes to advanced disease only in NAFLD. Virus-induced hepatic steatosis as seen in CHC-3 does not contribute significantly to liver fibrosis.

Adult↗
PubMed2006

Daily dose of interferon alpha-2b and ribavirin in treatment-naive patients with chronic hepatitis C virus genotype 1 infection: a randomised controlled study.

OBJECTIVE: The treatment of patients with hepatitis C virus (HCV) genotype 1 infection remains disappointing. METHODS: In 1999, we started a multicentre study comparing two regimens of recombinant interferon (IFN) alpha-2b plus ribavirin. Group A (90 patients) received ribavirin plus IFN alpha-2b 5 MU/day for 1 month (induction therapy) followed by IFN alpha-2b 5 MU thrice weekly for 5 months. Group B (85 patients) received ribavirin plus IFN alpha-2b 5 MU thrice weekly for 6 months. Responders in both arms received IFN alpha-2b 3 MU thrice weekly for a further 6 months. A follow-up evaluation was performed at 18 months. RESULTS: One hundred and seventy-five consecutive treatment-naive patients with HCV genotype 1 infection were enrolled in the study. A sustained virological response (SVR) was obtained in 51 (29%) patients: 28 in group A (31%) and 23 in group B (27%). HCV-RNA clearance was greater at 3 months among patients who received induction therapy (57 vs 39%; p < 0.02). Age, sex, and initial viral load did not influence the achievement of a SVR. HCV clearance at the end of the study was lower in cirrhotic patients (3/26 vs 48/149; p < 0.05). The only SVR in patients with cirrhosis occurred in those from group A (p < 0.05). Both regimens were well tolerated. CONCLUSIONS: This study confirms the low rate of SVR in treatment-naive patients with HCV genotype 1 infection treated with IFN alpha-2b plus ribavirin. A 4-week induction regimen was slightly superior to standard IFN alpha-2b plus ribavirin. Although the number of patients with cirrhosis was low, induction therapy seemed to be more effective in cirrhotics. Given its safety and tolerability, the induction regimen evaluated here may be a therapeutic option in treatment-naive patients with HCV genotype 1 infection.

Adult↗
PubMed2006

Epithelial microchimerism: consistent finding in human liver transplants.

BACKGROUND: Eleven liver biopsies from six male patients who received a liver transplant (LT) from female donors were examined in order to determine whether male host-derived hepatic cells were present in female grafts that exhibited minimal or important inflammatory damage. METHODS: Immunohistochemistry for epithelial cell type differentiation (anticytokeratin monoclonal antibody) and fluorescence in situ hybridization for XY chromosomes identification were performed on each slide. RESULTS: Host-derived hepatic cells were found in all except one transplant, with a frequency ranging from 2.3 to 25 per thousand of the total hepatocytes in the biopsy specimen. They were usually found as isolated cells scattered throughout the hepatic lobule; in one patient they were grouped into little clusters. Host-derived hepatic cells persisted throughout the histological follow up (up to 535 days after LT). Polyploidy for XY chromosome was observed. CONCLUSION: Hepatocytes derived from extra-hepatic stem cells are frequently found in small numbers in human liver grafts and persist over time.

Aged↗
PubMed2005

Prevalence of Helicobacter pylori infection and intestinal metaplasia in subjects who had undergone surgery for gastric adenocarcinoma in Northwest Italy.

AIM: To investigate the seroprevalence of Helicobacter pylori (H pylori) infection and its more virulent strains as well as the correlation with the histologic features among patients who had undergone surgery for gastric cancer (GC). METHODS: Samples from 317 (184 males, 133 females, mean age 69+/-3.4 years) consecutive patients who had undergone surgery for gastric non-cardia adenocarcinoma were included in the study. Five hundred and fifty-five (294 males, 261 females, mean age 57.3+/-4.1 years) patients consecutively admitted to the Emergency Care Unit served as control. Histological examination of tumor, lymph nodes and other tissues obtained at the time of surgery represented the diagnostic "gold standard". An enzyme immunosorbent assay was used to detect serum anti-H pylori (IgG) antibodies and Western blotting technique was utilized to search for anti-CagA protein (IgG). RESULTS: Two hundred and sixty-one of three hundred and seventeen (82.3%) GC patients and 314/555 (56.5%) controls were seropositive for anti-H pylori (P<0.0001; OR, 3.58; 95%CI, 2.53-5.07). Out of the 317 cases, 267 (84.2%) were seropositive for anti-CagA antibody vs 100 out of 555 (18%) controls (P<0.0001; OR, 24.30; 95%CI, 16.5-35.9). There was no difference between the frequency of H pylori in intestinal type carcinoma (76.2%) and diffuse type cancer (78.8%). Intestinal metaplasia (IM) was more frequent but not significant in the intestinal type cancer (83.4% vs 75.2% in diffuse type and 72.5% in mixed type). Among the patients examined for IM, 39.8% had IM type I, 8.3% type II and 51.9% type III(type III vs others, P = 0.4). CONCLUSION: This study confirms a high seroprevalence of H pylori infection in patients suffering from gastric adenocarcinoma and provides further evidence that searching for CagA status over H pylori infection might confer additional benefit in identifying populations at greater risk for this tumor.

Adenocarcinoma↗
PubMed2005

Interferon beta-1a alone or in combination with ribavirin: a randomized trial to compare efficacy and safety in chronic hepatitis C.

AIM: To compare the efficacy and safety of recombinant human IFN beta-1a alone or in combination with ribavirin in treatment-naive subjects with chronic hepatitis C. METHODS: Open, randomized trial was performed in 6 Italian tertiary centers: 102 of the 108 patients screened were randomized to receive 6 MIU of recombinant human IFN beta-1a subcutaneously daily for 24 wk, alone (Group 1, n = 51) or in combination with ribavirin 1,000 to 1,200 mg/d (Group 2, n = 51). RESULTS: The end-of-treatment virologic response rate was 29.4% in Group 1 and 41.2% in Group 2 (non-significant). Twenty-four weeks after stopping therapy, sustained virologic response rate was 21.6% in Group 1 and 27.4% in Group 2 (non-significant). All subjects in Group 1 completed treatment, while two subjects in Group 2 stopped therapy due to treatment-related adverse events. CONCLUSION: Recombinant human IFN beta-1a, alone or in combination with ribavirin, has an excellent safety profile and, may represent an alternative for chronic hepatitis C patients who are unable to tolerate pegylated alpha-interferon.

Adjuvants, Immunologic↗
PubMed2005

Long-term therapy with adefovir dipivoxil for HBeAg-negative chronic hepatitis B.

BACKGROUND: Treatment with adefovir dipivoxil for 48 weeks resulted in histologic, virologic, and biochemical improvement in patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B. We evaluated the effect of continued therapy as compared with cessation of therapy. METHODS: One hundred eighty-five HBeAg-negative patients with chronic hepatitis B were assigned to receive 10 mg of adefovir dipivoxil or placebo once daily for 48 weeks (ratio, 2:1). After week 48, patients receiving adefovir dipivoxil were again randomly assigned either to receive an additional 48 weeks of the drug or to switch to placebo. Patients originally assigned to placebo were switched to adefovir dipivoxil. Patients treated with adefovir dipivoxil during weeks 49 through 96 were subsequently offered continued therapy. The primary end points were changes in hepatitis B virus (HBV) DNA and alanine aminotransferase levels. RESULTS: Treatment with adefovir dipivoxil resulted in a median decrease in serum HBV DNA of 3.47 log copies per milliliter (on a base-10 scale) at 96 weeks and 3.63 log copies per milliliter at 144 weeks. HBV DNA levels were less than 1000 copies per milliliter in 71 percent of patients at week 96 and 79 percent at week 144. In the majority of patients who were switched from adefovir dipivoxil to placebo, the benefit of treatment was lost (median change in HBV DNA levels from baseline, -1.09 log copies per milliliter; only 8 percent of patients had levels below 1000 copies per milliliter at week 96). Side effects during weeks 49 through 144 were similar to those during the initial 48 weeks. Resistance mutations rtN236T and rtA181V were identified in 5.9 percent of patients after 144 weeks. CONCLUSIONS: In patients with HBeAg-negative chronic hepatitis B, the benefits achieved from 48 weeks of adefovir dipivoxil were lost when treatment was discontinued. In patients treated for 144 weeks, benefits were maintained, with infrequent emergence of viral resistance.

Adenine↗
PubMed2005

Neutral endopeptidase (EC 3.4.24.11) in cirrhotic liver: a new target to treat portal hypertension?

BACKGROUND/AIMS: In liver cirrhosis atrial natriuretic peptide (ANP) decreases portal vascular resistance and tributary flow. The enzyme neutral endopeptidase (NEP) degrades ANP and bradykinin and generates endothelin-1 from big-endothelin. We determined the effects of NEP inhibition by candoxatrilat on hormonal status, liver function and arterial and portal pressures in rats with CCl4-induced cirrhosis. METHODS: Two groups of seven control rats received 1 ml 5% glucose solution alone or containing 10 mg/kg candoxatrilat; three groups of 10 ascitic cirrhotic rats received placebo, 5 or 10 mg/kg candoxatrilat. NEP protein concentration and immunostaining were analyzed in normal and cirrhotic livers. RESULTS: In cirrhotic rats 10 mg/kg candoxatrilat significantly increased steady-state indocyanine green clearance (a parameter reflecting liver plasma flow) (P<0.01), decreased portal pressure (P<0.01), had no effect on arterial pressure and plasma renin activity but increased ANP plasma levels (P<0.05) and urinary excretions (P<0.01) of ANP and cGMP. In the cytosol fraction of rat cirrhotic livers a 280% increase in NEP content was found (P<0.01), chiefly localized in desmin-positive myofibroblast-like cells of fibrous septa. CONCLUSIONS: Candoxatrilat has few effects on systemic hemodynamics and hormonal status; its portal hypotensive action depends on effects exerted on intrahepatic vascular resistance.

Animals↗
PubMed2005

Digestive endoscopy is not a major risk factor for transmitting hepatitis C virus.

BACKGROUND: The potential role of digestive endoscopy as a mode for transmission of hepatitis C virus (HCV) is controversial. OBJECTIVE: To evaluate the role of digestive endoscopy in transmitting HCV by comparing the incidence of HCV infection in a cohort of patients undergoing endoscopy and in a cohort of blood donors. DESIGN: Prospective cohort study. SETTING: 3 endoscopic units and 2 blood banks in northwestern Italy. PATIENTS: The potentially exposed cohort consisted of 9188 outpatients consecutively recruited from 3 endoscopic units. Of 9008 patients negative for antibody to HCV (anti-HCV), 8260 (92%) were retested for anti-HCV 6 months after endoscopy. The unexposed cohort consisted of 51,230 healthy, anti-HCV-negative persons who donated blood at 2 blood banks in the same area and during the same time period; 38,280 of them (75%) were tested again for anti-HCV 6 to 48 months after the first blood donation (95,317 person-years of observation). MEASUREMENTS: Differences in the anti-HCV seroconversion rate between the exposed cohort (patients undergoing endoscopy) and the unexposed cohort (blood donors). Seroconversion was evaluated by a third-generation enzyme immunoassay for anti-HCV; persons positive for anti-HCV were tested for HCV RNA by polymerase chain reaction. RESULTS: All 8260 persons undergoing endoscopy remained negative for anti-HCV 6 months after the procedure (risk per 1000 persons, 0 [95% CI, 0 to 0.465]); in particular, none of the 912 patients who underwent endoscopy with the same instrument previously used on HCV carriers showed anti-HCV seroconversion (risk per 1000 persons, 0 [CI, 0 to 4.195]). Four blood donors became positive for anti-HCV and HCV RNA (mean follow-up, 2.49 years; 0.042 case per 1000 person-years [CI, 0.011 to 0.107 case per 1000 person-years]); each had undergone minor surgery before the second test. LIMITATIONS: In the endoscopy cohort, 8.3% of patients were lost to follow-up. CONCLUSIONS: These findings support the hypothesis that properly performed digestive endoscopy is not a major risk factor for the transmission of HCV.

Adult↗