Biomedical subjects

Giorgio Talamini

Publications and source records attributed to Giorgio Talamini.

13 recordsLinked to original sources

PubMed2006

Intraductal papillary mucinous neoplasms and chronic pancreatitis.

BACKGROUND: Intraductal papillary mucinous neoplasms (IPMNs) may present with clinical and radiological pictures resembling those of chronic pancreatitis (CP). AIMS: To compare the clinical and epidemiological characteristics of patients suffering from CP with those of patients suffering from IPMN. To assess whether CP is associated with an increased risk of developing IPMN. METHODS: In our departments, from 1981 to 1998, we prospectively followed 473 patients suffering from CP, including 93 cases of chronic obstructive pancreatitis (COP), and 45 patients with a histologically confirmed diagnosis of IPMN. Another 6 patients had an initial diagnosis of CP and a subsequent diagnosis of IPMN. RESULTS: Patients with IPMN were more often female (females 53 vs. 15%; p < 0.001), were older (mean age 63.1 vs. 42.8 years; p < 0.001), drank less alcohol (19 vs. 107 g/day; p < 0.001) and smoked fewer cigarettes (mean 8 vs. 21 cigarettes/day) than CP patients. These results were also confirmed when considering only patients with COP. The 6 patients with a subsequent diagnosis of IPMN were males (p n.s.) with a mean age of 51.4 years (p < 0.05). Only 1 patient was a drinker (p < 0.05) and 4 were smokers (p n.s.). Comparing CP and IPMN, logistic regression analysis selected sex, age, alcohol and smoking, whereas only sex and age were selected when comparing COP vs. IPMN. CONCLUSIONS: In general patients with IPMN present different epidemiological characteristics than those with CP and the subgroup with COP. The clinical and pathological features suggest that in most cases IPMN is the cause of CP and not vice versa.

Adenocarcinoma, Mucinous↗

PubMed2006

Reference values for exhaled nitric oxide (reveno) study.

BACKGROUND: Despite the widespread use of fractional exhaled nitric oxide (FENO) as a biomarker of airways inflammation, there are no published papers describing normal FENO values in a large group of healthy adults. OBJECTIVE: The aim of this study was to establish adult FENO reference values according to the international guidelines. METHODS: FENO was measured in 204 healthy, non-smoking adults with normal spirometry values using the on-line single-breath technique, and the results were analysed chemiluminescently. RESULTS: The main result of the study was the significant difference in FENO values between men and women, thus indicating that gender-based reference FENO values are necessary. The FENO levels obtained at expiratory flows of 50 ml/s ranged from 2.6 to 28.8 ppb in men, and from 1.6 to 21.5 ppb in women. CONCLUSION: We propose reference FENO values for healthy adult men and women that could be used for clinical and research purposes.

Adult↗

PubMed2005

Prevalence of hepatitis A among drug users in north-eastern Italy. Is vaccination necessary in low prevalence areas?

BACKGROUND: The authors report on the prevalence of, and risk factors for, hepatitis A virus (HAV) in a group of drug users in Italy. METHODS: 404 heroin users were recruited and compared with a control group of 107 subjects in the general population. RESULTS: Drug users born in north-eastern Italy have a prevalence of anti-HAV similar to the control group. A much higher prevalence was found in drug users born in southern Italy. CONCLUSION: The similar prevalence of anti-HAV in drug users born in north-eastern Italy and in the general population, suggests that their lifestyle does not involve a substantial additional risk of HAV. The much higher prevalence found in drug users born in southern Italy is more likely to be related to infection during infancy.

Adult↗

PubMed2005

Duodenal acidity may increase the risk of pancreatic cancer in the course of chronic pancreatitis: an etiopathogenetic hypothesis.

Chronic pancreatitis patients have an increased risk of developing pancreatic cancer. The cause of this increase has yet to be fully explained but smoking and inflammation may play an important role. To these, we must now add a new potential risk factor, namely duodenal acidity. Patients with chronic pancreatitis very often present pancreatic exocrine insufficiency combined with a persistently low duodenal pH in the postprandial period. The duodenal mucosa in chronic pancreas patients with pancreatic insufficiency has a normal concentration of s-cells and, therefore, the production of secretin is preserved. Pancreatic ductal cells are largely responsible for the amount of bicarbonate and water secretion in response to secretin stimulation. When gastric acid in the duodenum is not well-balanced by alkaline pancreatic secretions, it may induce a prolonged secretin stimulus which interacts with the pancreatic ductal cells resulting in an increased rate of ductular cell activity and turnover. N-Nitroso compounds from tobacco, identified in human pancreatic juice and known to be important carcinogens, may then act on these active cells, thereby increasing the risk of cancer. Duodenal acidity is probably of particular concern in patients who have undergone a duodenum-preserving pancreatic head resection, since, in this anatomic situation, pancreatic juice transits directly via the jejunal loop, bypassing the duodenum. Patients undergoing a Whipple procedure or side-to-side pancreaticojejunostomy are probably less critically affected because secretions transit, at least in part, via the papilla. If the duodenal acidity hypothesis proves correct, then, in addition to stopping smoking, reduction of duodenal acid load in patients with pancreatic insufficiency may help decrease the risk of pancreatic cancer.

Alcohol Drinking↗

PubMed2004

DNA breaks as measured by the alkaline comet assay in exfoliated cells as compared to voided urine cytology in the diagnosis of bladder cancer: a study of 105 subjects.

In this study we evaluated the clinical usefulness of identifying urothelial cells with increased DNA damage with the alkaline comet assay and compare it with voided urine cytology for the assessment of markers indicative of bladder cancer. The analysis was carried out on 105 subjects having clinical suspicion of bladder cancer, and who had undergone cytology for the first time. Urine cytology and alkaline comet assay were performed on the same fresh urine samples obtained from each patient. The subjects were divided according to negative or positive cytology. The Mann-Whitney U-test showed that the comet parameters (tail moment, tail length, and % of DNA in the tail) and the numbers of comets (cells with an arbitrary cut-off value of head intensity <90% of DNA content) in subjects positive in both tests were significantly higher than in the negative group. Sensitivity, specificity, and positive and negative predictive value of the comet assay were compared with those of cytology, which is regarded as the gold standard. Sensitivity was 71.4%, specificity was 91.8%, positive and negative predictive values were 38.5 and 97.8, respectively. Two subjects negative in the comet assay were positive in cytology. Eight patients were positive in the comet assay and negative for cytology. Interestingly, one of these eight patients was later found positive for cytology. Logistic regression analysis indicates that the tail moment is significantly associated with an increased risk for positive cytology.

Aged↗

PubMed2003

Determinants of platelet activation in human essential hypertension.

Experimental data suggest that oxidative stress might be enhanced in hypertension and contribute to platelet activation. We hypothesized that both oxidative stress and platelet activation could be related to the clinical characteristics of hypertensive patients. The urinary excretion of 11-dehydrothromboxane (TX) B2, reflecting in vivo platelet activation, was measured in 75 patients with mild to severe essential hypertension and 75 pair-matched, healthy controls. The urinary excretion of 8-iso-prostaglandin (PG) F2alpha was determined as an index of in vivo lipid peroxidation. Urinary 11-dehydro-TXB2 was significantly higher in essential hypertensives compared with controls. Although no statistically significant difference in urinary 8-iso-PGF2alpha was observed between patients and controls, plasma vitamin C was lower and plasma homocysteine higher in hypertensive patients than in controls. Both urinary 11-dehydro-TXB2 and 8-iso-PGF2alpha were higher in patients with advanced hypertensive retinopathy compared with patients without retinopathy. Multivariate linear regression analysis identified urinary 8-iso-PGF2alpha, plasma fibrinogen, homocysteine, and vitamin E as the only variables independently correlated with urinary 11-dehydro-TXB2. Logistic regression analysis showed that high urinary 8-iso-PGF2alpha, plasma fibrinogen, and homocysteine, as well as low plasma vitamin E, advanced retinopathy, elevated diastolic blood pressure, and the absence of antihypertensive treatment, were predictors of high urinary 11-dehydro-TXB2. We demonstrated increased oxidative stress and persistent platelet activation in essential hypertensives with advanced vascular lesions. These findings might help identify hypertensive patients who are at increased risk of cardiovascular events and who might benefit from long-term antiplatelet therapy.

Adolescent↗

PubMed2003

SEL1L expression in pancreatic adenocarcinoma parallels SMAD4 expression and delays tumor growth in vitro and in vivo.

Recent data suggest that SEL1L may play an important role in pancreatic carcinoma, similar to breast cancer, where the expression of SEL1L has been associated with a reduction in both proliferative activity in vitro and clinical tumor aggressiveness. To investigate this possibility, we examined the expression of Sel1L in a series of primary pancreatic carcinomas by immunohistochemistry and characterized the effects of Sel1L overexpression both in vitro and in vivo. In 74 pancreatic cancers analysed, 36% lacked Sel1L expression, although there was no significant correlation between the expression of Sel1L and any clinicopathologic parameter, including survival. However, immunohistochemical reactivity for Sel1L and Dpc4/Smad4 was concordant in 69% of cases (chi(2) test P&<0.004). Overexpression of SEL1L in stably transfected pancreatic cancer cells caused both a decrease in clonogenicity and anchorage-independent growth as well as a significant increase in the levels of activin A and SMAD4. When implanted in nude mice, Suit-2-SEL1L-overexpressing clones displayed a considerably reduced rate of tumor growth. Thus, it can be hypothesized that Sel1L plays an important function in the growth and aggressiveness of pancreatic carcinoma. Moreover, our data provide evidence that SEL1L has an impact on the expression of genes involved in regulation of cellular growth, possibly through the TGF-beta signaling pathway.

Activins↗

PubMed2003

Factors associated with hepatitis C virus infection in injection and noninjection drug users in Italy.

We describe the prevalence of hepatitis C virus (HCV) infection among noninjection users of heroin in Italy and compare the prevalence of HCV infection among noninjection drug users (NIDUs) and injection drug users (IDUs). Multiple logistic regression analysis of data from NIDUs showed that hepatitis B virus (HBV) infection status was the only independent predictor of HCV seroprevalence. Among IDUs, the number of years of drug use and HBV and human immunodeficiency virus infection status were independent predictors of HCV seropositivity. We found an HCV infection prevalence of 20% among NIDUs. This rate was much lower than that for IDUs, who are 11 times more likely to have antibodies against HCV. The prevalence of HCV infection was much higher than that of HBV infection among the IDUs. In contrast, the prevalence of HBV infection was slightly higher than that of HCV infection among unvaccinated NIDUs. The prevalence of HCV infection among long-term IDUs approached true population saturation; among long-term NIDUs, however, it appeared to plateau at approximately 40%. Additional research on HCV infection among NIDUs is needed to develop a strategic prevention program for this patient subgroup.

Adult↗

PubMed2002

Ampulla of vater cancers: T-stage and histological subtype but not Dpc4 expression predict prognosis.

Loss of immunohistochemical expression of Dpc4 occurs in about 50% of pancreatic ductal cancers and its loss correlates with DPC4/Smad4 gene inactivation. Dpc4 expression was also lost in 6 of 16 (37%) ampulla of Vater cancers (AVCs) previously analyzed. Furthermore, chromosomal losses involving 18q, where DPC4 is located, have been observed in 34% of AVCs and are associated with decreased survival. To evaluate the possibility that expression of Dpc4 may be correlated with survival, we analyzed 89 AVCs for inactivation of DPC4 by immunohistochemical staining. Thirty-seven cases showed no expression of Dpc4 (41%). Multivariate survival analysis was performed including age, sex, tumor size, histological subtype (intestinal or pancreatobiliary), grade of differentiation, T-stage, lymph-node metastases and Dpc4 status. T-stage and histological subtype were selected as independent prognostic factors, while Dpc4 immunostaining was not significantly associated with any clinicopathological variable, including histological subtype. Although Dpc4 expression is of no clinical relevance, its involvement in AVC gives additional weight to the hypothesis that, among all pancreatic exocrine and endocrine tumors, only AVC and common ductal adenocarcinomas have similar molecular fingerprints. Moreover, comparison of the frequencies of allelic loss on chromosomal arm 18q and the loss of Dpc4 expression (34% and 41%, respectively) is highly suggestive that DPC4 is the major target of these losses.

Adult↗

PubMed2002

Lead induced DNA strand breaks in lymphocytes of exposed workers: role of reactive oxygen species and protein kinase C.

Lead and lead compounds play a significant role in modern industry; a wide variety of population is at risk of occupational exposure and lead is suspected to be a human carcinogen. The biochemical and molecular mechanisms of lead toxicity are poorly understood, but emerging data suggest that some of the effects of lead may be due to its interference with calcium in the activation of protein kinase C (PKC) and/or through production of reactive oxygen species (ROS). Many of these results are conducted in vitro on cell lines or ex vivo on human lymphocytes treated in vitro. We, therefore, performed a study on the induction of DNA damage, using the alkaline comet assay, in lymphocytes of battery plant workers. To elucidate in vivo the mechanism(s) responsible for this effect, we determined ROS production, and glutathione (GSH) levels in living cells using the fluorescent probe (2',7'-dichlorofluorescein and monochlorobimane, respectively). Subcellular fractions were obtained from sonicated lymphocytes; cytosolic and membrane expression of PKC isoforms (alpha, and zeta) was evaluated after electrophoresis by immunoblot analysis. The results indicate that lead-exposed workers have significantly elevated levels of DNA breaks compared to the unexposed group. A multivariate analysis of variance (ANOVA) shows that the most common confounding factors (smoking, drinking and age) have no synergistic effects with lead-exposure on the comet parameters or on GSH levels and ROS production. The logistic regression analysis distinguishing the exposed and non-exposed indicates that only GSH with tail moment are selected as significant risk factors. There is a significant positive correlation with ROS production and negative correlation with GSH levels. The content of PKC alpha in cytosol and membranes is decreased 40% (indicating a down-regulation of protein), whereas PKC zeta isoform is not modified in an evident manner. Our results suggest that lead-exposure induces an increase of DNA breakage with an alternate cellular redox state and a significant down-regulation of PKC alpha, suggesting that this metal may act as a tumor promoter.

Adult↗

PubMed2002

Effects of gabexate mesilate, a protease inhibitor, on human sphincter of Oddi motility.

Gabexate mesilate is an antiprotease drug, which reduced the severity of pancreatitis and frequency of post-ERCP pancreatitis. In dogs gabexate inhibits sphincter of Oddi motility but no data are available in humans. The aim of this study was to verify by manometry the action of gabexate on human sphincter of Oddi motility. We enrolled 12 patients with idiopathic recurrent pancreatitis (eight males, five females, mean age 46 +/- 8 years). Standard preendoscopic sphincter of Oddi manometry was done in basal conditions and during infusion of gabexate 20 mg/min: basal pressure, amplitude and frequency of phasic contractions, and motility index (amplitude per frequency) were calculated before and after gabexate injection. Statistical analysis was performed by using Wilcoxon rank test for paired data. Six patients had a manometric diagnosis of stenosis (basal pressure greater than 40 mm Hg); six had normal findings. Phasic activity was not evaluable in five patients with stenosis. Basal pressure was unaffected by drug infusion, while gabexate caused a significant reduction of phasic activity, both in terms of frequency (4.5 +/- 1 vs 3.6 +/- 1; P < 0.05) and amplitude (157.4 +/- 44 vs 80.0 +/- 32; P < 0.05) of contractions. Motility index was reduced on average by 49%. In conclusion, this pilot study confirms, in patients with acute recurrent pancreatitis, the inhibitory action of gabexate on sphincter of Oddi motility already described in dogs. This action needs to be revaluated at therapeutic dosages. On the other hand, prophylactic use of the drug should be avoided during sphincter of Oddi manometry, in order to avoid false negative results.

Acute Disease↗

PubMed2002

Compliance with hepatitis B vaccination in 1175 heroin users and risk factors associated with lack of vaccine response.

AIMS: To investigate the feasibility of hepatitis B vaccination among heroin users, assessing adherence to the vaccination schedules and identifying factors associated with antibody response. DESIGN AND PARTICIPANTS: A large cohort study in nine public centres for drug users (PCDUs) in north-eastern Italy, with data collected between January 1989 and December 1998. A total of 1175 heroin users were selected and vaccinated with a recombinant vaccine using two schedules (0-1-6 months and 0-1-2 months). FINDINGS: Eighty-eight per cent of patients completed the vaccination series and a protective antibody response occurred in 77% of subjects. Completion of the vaccination series was not related to the length of the vaccination schedule or whether the patient was still in drug abuse treatment at the end of the series, but was related strongly to the number of patients enrolled at each PCDU (Spearman correlation = - 0.93, P < 0.001). Four variables were significantly associated with lack of seroconversion in response to vaccination: older age (AOR = 0.91 per year, 95% CI 0.88-0.94, P < 0.001), 2-month vaccination schedule (AOR = 3.10, 95% CI 2.06-4.68, P < 0.001), HCV seropositivity (AOR = 0.69, 95% CI 0.47-0.99, P = 0.04), HIV seropositivity (AOR = 0.27, 95% CI 0.10-0.77, P = 0.01). CONCLUSIONS: A large-scale, multi-site hepatitis B vaccination programme for heroin users proved feasible and effective. The factors associated with a lack of antibody response may be useful in identifying patients who would benefit most from routine post-vaccination testing, with booster doses for non-responders. These results suggest that hepatitis B vaccination for drug users should become a routine public health practice.

Adult↗

PubMed2002

Prevalence of tuberculosis infection and comparison of multiple-puncture liquid tuberculin test and Mantoux test among drug users.

In order to determine the prevalence of latent infection due to Mycobacterium tuberculosis in drug users and to provide centres for drug users with a practical tool for tuberculosis screening, 237 drug users were subjected to the Monotest and, for reference purposes, to the Mantoux test. The overall prevalence of subjects with a tuberculin skin reaction size > or = 5 mm in the Mantoux test was 25.7%; utilizing a cut-off of > or = 10 mm, the prevalence was 11.4%. Irrespective of cut-off, the Monotest showed a sensitivity of > 90% and a specificity of > 80%. At a prevalence of 25.7%, and with cut-offs of > or = 5 or > or = 10 mm, the positive predictive value was 83% or 62.2%, respectively. Irrespective of cut-off, the negative predictive value was > 97%. In conclusion, the Monotest proved satisfactory as a tool for epidemiological screening in a population with a high prevalence for latent tuberculosis, namely drug users.

Adult↗