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T Bianchi

Publications and source records attributed to T Bianchi.

At least 19 recordsLinked to original sources
PubMed2006

The tumor suppressor p16Ink4a regulates T lymphocyte survival.

In contrast to other cell cycle inhibitors, the tumor suppressor p16Ink4a is not detectable or expressed at very low levels in embryonic and adult mouse tissues, and therefore it has often been considered as a specialized checkpoint protein that does not participate in the control of normal cell cycle progression. However, Ink4a-/- mice possess increased thymus size and cellularity, thus suggesting the involvement of p16(Ink4a) in the control of thymocyte proliferation. In this study, we found increased numbers of CD8 and CD4 T lymphocytes in thymus and spleen from Ink4a-/- mice. Unexpectedly, this was not related to an increase in T-cell division rates, which were similar in lymphoid organs of Ink4a-/- and wild-type mice. In contrast, T-cell apoptosis rates were significantly decreased in thymus and spleen from Ink4a-/- mice. Moreover, whereas p16Ink4a-deficient and wild-type T cells were equally sensitive to Fas or TCR-mediated apoptosis, the former were clearly more resistant to apoptosis induced by oxidative stress or gamma irradiation. Our results indicate that p16Ink4a function is associated with T-cell apoptosis, and subsequently contributes to the control of T-cell population size in lymphoid organs.

Animals↗
PubMed2005

Presence of high-risk mucosal human papillomavirus genotypes in primary melanoma and in acquired dysplastic melanocytic naevi.

BACKGROUND: Some studies have shown that cutaneous and mucosal melanoma biopsy specimens harbour human papillomavirus (HPV), suggesting that this virus may play a role in development and progression of the tumour. OBJECTIVES: To investigate the presence of HPV DNA and the prevalence of different high-risk mucosal HPV genotypes in primary melanoma (PM) and in acquired dysplastic melanocytic naevi (ADMN). METHODS: Fifty-one PMs from 18 men and 33 women (median age 55.5 years), 33 ADMN from 15 men and 18 women (median age 35.1 years) and 20 control skin samples from nine men and 11 women (median age 43.5 years) were studied. All diagnoses were made after histological analysis. HPV DNA analysis was made using two different polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA) methods, namely MY-PCR and GP-PCR. RESULTS: Using GP-PCR, mucosal HPVs were detected in 14 PMs (27%; P = 0.0166) and eight ADMN (24%; P = 0.0367), while with MY-PCR, mucosal HPVs were found in 11 PMs (22%; P = 0.04) and five ADMN (15%; P not significant). All control skin samples were negative for mucosal HPVs with both DNA amplification procedures. CONCLUSIONS: Using our PCR-ELISA methods, the detection of mucosal high-risk HPV genotypes in 24% of precursor lesions (ADMN) and in 27% of PMs adds to the body of evidence indicating a colocalization of mucosal HPV and tumoral melanocytic pathologies.

Adolescent↗
PubMed2001

Asbestos exposure in malignant mesothelioma of the pleura: a survey of 557 cases.

A series of 557 malignant mesotheliomas of the pleura diagnosed in the Trieste-Monfalcone area, Italy, in the period 1968-2000 were reviewed. The series included 492 men and 65 women, aged between 32 and 93 years (median age 69 years). Necropsy findings were available in 456 cases (82%). Occupational histories were obtained from the patients themselves or from their relatives by personal or telephone interviews. Routine lung sections were examined for asbestos bodies in 442 cases. In 109 cases isolation and counting of asbestos bodies were performed. A majority of people had histories of working in the shipyards. Asbestos bodies were observed in lung sections in 67% of the cases. Lung asbestos body burdens after isolation ranged between 20 bodies and about 10 millions of bodies/g dried tissue. Latency periods (time intervals between first exposure to asbestos and death) ranged between 14 and 75 years (mean 48.8 years, median 51.0). Latency periods among insulators and dock workers were shorter than among the other categories. High asbestos consumption occurred in many countries in the 1960s and in the 1970s. The data on latency periods obtained in the present study suggest that a world mesothelioma epidemic has to be expected in the coming decades.

Adult↗
PubMed2000

Malignant mesothelioma in central and Eastern Europe.

To obtain data on mesothelioma incidence in Central and Eastern Europe, a short questionnaire was sent to 83 researchers from 19 countries. The questions referred to the approximate number of mesotheliomas diagnosed per year in the country, degree of asbestos consumption, and percentage of lung carcinomas attributable to asbestos. Answers were received from 12 countries. For some major asbestos producers and/or consumers, such as Russia and Ukraine, mesothelioma data were unavailable or unreliable. In various countries of Central-Eastern Europe, the crude incidence of mesothelioma appeared to be lower than in Western countries. The reported annual numbers of mesotheliomas were 120 in Poland, 133 in Romania, and 78 in Hungary. Among the countries with a population of 5 million or less, the highest incidence was observed in Croatia (46 cases per year, peritoneal tumors not included). Data on the percentage of asbestos-related lung carcinomas are lacking. The knowledge about asbestos related cancer in Central and Eastern Europe remains fragmentary. Further investigations in this relevant area of public health should be encouraged.

Asbestos↗
PubMed1998

Thymic lineage commitment rather than selection causes genetic variations in size of CD4 and CD8 compartments.

During their development, immature CD4+ CD8+ thymocytes become committed to either the CD4 or CD8 lineage. Subsequent complete maturation of CD4+ and CD8+ cells requires a molecular match of the expressed coreceptor and the MHC specificity of the TCR. The final size of the mature CD4+ and CD8+ thymic compartments is therefore determined by a combination of lineage commitment and TCR-mediated selection. In humans and mice, the relative size of CD4+ and CD8+ peripheral T cell compartments shows marked genetic variability. We show here that genetic variations in thymic lineage commitment, rather than TCR-mediated selection processes, are responsible for the distinct CD4/CD8 ratios observed in common inbred mouse strains. Genetic variations in the regulation of lineage commitment open new ways to analyze this process and to identify the molecules involved.

Animals↗
PubMed1998

Assessment using ELISA of the herd immunity levels induced in cattle by foot-and-mouth disease oil vaccines.

The development of a liquid-phase blocking sandwich ELISA (LPBE) to measure antibodies (Ab) produced in cattle with the O, A and C foot-and-mouth disease virus (FMDV) types of commercial vaccines used in Argentina is described. The test was specific: 99% of naïve cattle sera (n = 130) gave titres below log10 = 1.2, and none had a titre above log10 = 1.5. Comparative studies with serum neutralization test (SNT) using sera from cattle which received one or more vaccine doses is reported. The overall rank correlation coefficient (Spearman's rho, rs) between SNT and LPBE were highly significant (rs > 0.67, P < 0.0001) for all vaccine strains. LBPE Ab titres on sera collected 90 days post vaccination were compared with results of cattle protection tests by applying a logistic regression. The minimum Ab titres at which 85% and 75% of the cattle were protected for each FMDV type were determined in order to interpret field Ab data in terms of protection. Application of this method allows large scale serological examinations to monitor antibody levels in vaccinated animals as an indirect indicator of the FMD control program status in the field. Its use in the evaluation of commercial batches of FMD vaccine is discussed.

Animals↗
PubMed1996

Early and intermediate term results of Carpentier's repair for Ebstein's anomaly.

BACKGROUND: Various surgical techniques have been used for correction of Ebstein's anomaly. This paper reports our early and intermediate term results for repair of this disease using the technique initially employed by Carpentier. PATIENTS AND METHODS: Since December 1987 through December 1991, 13 consecutive patients with Ebstein's anomaly underwent a Carpentier's type of repair. Their mean age was 16.3 years ranging from 6 to 51 years. The indications for operation were advanced NYHA functional class (III-IV) in 4 cases, cyanosis in 4, severe arrhythmia in 3 and cyanosis with arrhythmia in 2. Associated malformations were present in 9 patients. Eight had an atrial septal defect and four of them had, also, mitral prolapse whereas the remaining patient had a ventricular septal defect with subaortic stenosis. Tricuspid regurgitation was severe in 12 cases and moderate in one. According to the anatomo-functional classification described by Carpentier, seven patients had Ebstein's type C, whereas a type B was present in five patients and only one patient had a type A. RESULTS: There were three hospital deaths all of which occurred in patients with type C anomaly. Causes of death were respectively low output syndrome, sepsis and cerebral hemorrhage. Follow-up ranged from 49 to 105 months (median 58 months). There were no late deaths and all patients were in NYHA functional class I or II. Preoperative arrhythmia was improved or abolished in 4 out of 5 patients. Echocardiography showed that tricuspid regurgitation was absent in 2, mild in 4, moderate in 3 and severe in the remaining patient. CONCLUSIONS: Repair of Ebstein's anomaly, using the technique reported by Carpentier, can be accomplished with an acceptable operative risk and satisfactory intermediate term results. Echocardiography has an important role in the diagnosis of Ebstein's anomaly as well as in the indications and timing for repair and it is particularly useful for intra- and postoperative monitoring and anatomofunctional evaluation.

Adolescent↗
PubMed1995

Assessment of foot and mouth disease vaccine potency by liquid-phase blocking ELISA: a proposal for an alternative to the challenge procedure in Argentina.

The lowest expected protection (LEP) at a 95% confidence of 245 foot and mouth disease (FMD) commercial vaccines was calculated from the titres of liquid-phase blocking sandwich ELISA (lpELISA) of cattle sera obtained from 3920 animals at 60 days post-vaccination (d.p.v.) and challenged with live virus at 90 d.p.v. It was found that LEP evaluation is highly specific (i.e. it is able to predict the failure in 100% of the cases) although its ability to predict the challenge (PG test) approval (i.e. sensitivity) comprised only 65% of the vaccines that passed the trial. It was possible, nevertheless, to improve the sensitivity of the evaluation by using an alternative coefficient (Ro), exclusively dependent on the number of animals exhibiting the highest and lowest lpELISA titres in a particular vaccine trial. This coefficient was capable of predicting the PG approval of 90% of the vaccines, yet maintaining acceptable levels of safety (87% of specificity). Based on these results and as a first step towards the replacement of the challenge protocol in Argentina, we propose a swift approval for commercialization of FMD vaccines which are able to reach the highly restricting LEP passmark of 82%, and the rejection of those not reaching the 50% LEP limit. More extensive experience with this new protocol will allow a finer adjustment of the LEP and Ro values and to set more precisely the cut-off points for direct approval or disapproval of vaccines by lpELISA, eliminating the use of live FMDV in the field.

Animals↗
PubMed1994

Treatment of bile leaks from the cystohepatic ducts after laparoscopic cholecystectomy.

The cystohepatic ducts represent accessory bile ducts of variable size which frequently travel within the gallbladder fossa or in the posterior wall of the gallbladder. These ducts can be injured during laparoscopic cholecystectomy and can result in bile collections if transected. Successful treatment by operative means or radiologically guided percutaneous drainage is possible, but endoscopic management has several advantages. We describe cases managed by endoscopic retrograde cholangiopancreatography (ERCP) with stent placement and discuss the advantages of this method. Also discussed is the anatomy of these accessory bile ducts, additional management options, and techniques for avoiding this injury during open or closed cholecystectomy.

Aged↗
PubMed1994

A new frontier for cardiac therapy. Principles and practice of aerobic cardiac surgery.

As recently reported in the literature, aerobic cardiac surgery (normothermic total body perfusion + continuous normothermic blood cardioplegia) might achieve optimal heart protection by virtually eliminating myocardial ischemia during aortic cross-clamping. Two-hundred and fifty consecutive patients underwent cardiac surgery by this technique. Mean cross-clamp time was 72.6 +/- 30.7 minutes. Ten patients (4%) died, 20 (8%) needed major inotropic support and 8 (3.2%) required circulatory assistance. Two-hundred and twenty-three patients (89.2%) returned spontaneously to normal sinus rhythm and 8 (3.2%) had evidence of perioperative myocardial infarction. Nineteen patients (7.6%) had a cross-clamp time longer than 120 minutes and no significant difference in mortality was observed with those undergoing a shorter cross-clamping. When comparing 154 patients receiving retrograde continuous normothermic blood cardioplegia induction with 46 receiving antegrade induction, no difference was found in perioperative parameters, mortality and morbidity. By univariate analysis, impaired preoperative LV performance was identified as the only risk factor for operative mortality. In our experience aerobic cardiac surgery appears most suitable for emergency and redo operations, extensive coronary revascularization, complex mitral reconstruction, aortic valve replacement (particularly with unstented biological prostheses), cardiac transplants and whenever two or more valvular and/or coronary procedures are associated. Retrograde induction is as effective as antegrade and simplifies the technique, facilitating unmodified continuous normothermic blood cardioplegia in different anatomical and clinical situations.

Adolescent↗
PubMed1993

Helicobacter pylori detection: a quality and cost analysis.

Histopathologic interpretation of hematoxylin and eosin (H&E)-stained endoscopic biopsies is a common method for identifying Helicobacter pylori. Few studies report the accuracy of this method, and none have compared costs of other diagnostic methods. In the clinical setting of a community hospital using standard diagnostic techniques, the purpose of this study were to determine 1) the comparative sensitivities and specificities of the H&E stain, the Warthin-Starry silver stain, the Giemsa stain, and the CLOtest; 2) the sensitivity and specificity of an "experienced" pathologist in identifying H. pylori by H&E stains, compared with a rotating pathology faculty; and 3) the time to diagnosis (turnaround time) and current patient charges for each diagnostic method. Bacterial identification by the silver stain (or a combination of other tests which were likely to compensate for false-positive and false-negative silver stains) were used as the diagnostic standard in evaluating 94 consecutive cases with the following results: The H&E stain interpreted by the rotating pathology staff was the least sensitive method and one of the least specific tests that were studied. The silver and Giemsa stains were equally sensitive in identifying H. pylori; the silver stain was more specific. The CLOtest was less sensitive than the silver and Giemsa stains, but was equally specific. CLOtest was similar in sensitivity to the H&E stain examined by the "experienced" pathologist, but was more specific. An experienced pathologist was significantly more sensitive than the rotating pathologists in evaluating H&E-stained slides. Therefore, if H&E stains are used to identify H. pylori, which is a common practice, it may be advantageous to use an experienced pathologist. The CLOtest was a simple, rapid, and cost effective substitute for H&E stains in the identification of H. pylori.

Biopsy↗