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G Pisani

Publications and source records attributed to G Pisani.

At least 19 recordsLinked to original sources
PubMed2006

The role of vascular endothelial growth factor and its receptor Flk-1/KDR in promoting tumour angiogenesis in feline and canine mammary carcinomas: a preliminary study of autocrine and paracrine loops.

Vascular Endothelial Growth Factor (VEGF) and its receptor KDR are involved in the regulation of angiogenesis and are up-regulated in a number of tumours in humans and in particular, breast cancer. We therefore evaluated the prognostic potential of the angiogenetic process in feline and canine mammary carcinomas by the immunohistochemical assessment of VEGF expression and micro vessel density (MVD) quantification and examined the interplay between VEGF and KDR. These variables were related to some relevant clinicopathological parameters and to overall survival (OS). VEGF and KDR expression were evaluated in epithelial, stromal and endothelial compartments in order to identify autocrine and/or paracrine loops. In dogs an increased VEGF expression did not show any statistical correlation with the clinicopathological parameters examined and was not correlated to a poorer prognosis. MVD was found to be significantly correlated to the histologic type (P=0.04), tumour grading (P=0.02), and to the OS (P=0.01). In cats VEGF expression was significantly correlated to tumor grading (P=0.01) and OS (P=0.03), while no significant associations were found between MVD and the other parameters. VEGF and KDR were found to be detected on the epithelial, and/or endothelial and/or stromal cells of the carcinomas in both species, suggesting indications for some possible autocrine and paracrine loops. Our results encourage further studies on the possible prognostic role of VEGF and MVD in canine and feline mammary tumours and on the role of growth factors and their receptors in promoting tumour proliferation and an "angiogenetic shift". The VEGF/KDR system may play a role in malignant transformation and tumor progression.

Animals↗
PubMed2006

Androgen receptor expression in normal, hyperplastic and neoplastic hepatoid glands in the dog.

Neoplasms of the perianal glands are common in the dog, particularly in the male. The occurrence of these tumours appears to be hormone related and castration, without excision of the tumour, has sometimes resulted in regression of the tumour. The aim of this study was to investigate the expression of androgen receptors (AR) in normal, hyperplastic and neoplastic hepatoid glands in the dog. Thirty-one samples of canine hepatoid gland tissues were investigated. The lesions, classified according to WHO criteria, were comprised of 19 hyperplastic tissues, 10 benign lesions (2 hepatoid gland epithelioma and 8 hepatoid adenomas), and 19 carcinomas. Five samples from normal hepatoid glands were also investigated. The AR expression was evaluated by immunohistochemistry using a streptavidin-biotin peroxidase method. The immunoexpression was scored by two pathologists as the percentage of positive nuclei. The intensity of staining was also considered. AR expression was detected in all normal and abnormal glands. However, in hyperplastic tissues the percentage of positive nuclei was significantly higher than in normal tissue and especially in reserve basaloid cells. A similar increase in the percent of positive nuclei was also observed in hepatoid epitheliomas, while in hepatoid adenoma the percent of AR-immunolabelling was only slightly increased compared to normal tissue. In hepatoid carcinomas the percent of AR-positive cells was similar to that observed in benign tumours. The grade of differentiation of hepatoid carcinomas did not affect AR expression. These results demonstrate that increased AR expression is maintained throughout perianal gland cancer progression and that hepatoid gland carcinomas still express AR. Although further studies may be required to evaluate the hormonal background of these diseases, dogs bearing those carcinomas might benefit from castration or anti hormonal therapy.

Anal Gland Neoplasms↗
PubMed2006

[Knowledge and use of Pap-smear among HIV-positive women].

AIM: HIV-positive women are at increased risk for preneoplastic lesions and invasive cervical cancer (ICC). The occurrence of these lesions can be substantially reduced by appropriate cervico-vaginal screening protocols (i.e., Pap-test). The aim of study was to assess: 1) awareness of Pap-smear and 2) the association between awareness of Pap-smear and screening attitudes of HIV-positive women. METHODS: Three-hundred and ninety HIV-positive women who attended the HIV outpatient gynecological unit of the National Institute for Infectious Diseases, Rome, from January 2003 to April 2005 were included in this investigation. These 390 women were interviewed to assess whether they were aware that Pap-test was a preventive tool against cervical cancer. In addition, past history of Pap-test, socioeconomic condition, history of HIV infection, and sexual habits were investigated. Odds ratios (OR) and 95% confidence intervals (CI) were used to assess the association between knowledge of Pap-test and covariates. RESULTS: Of these 390 HIV-positive women, 54.6% were not aware that Pap-test could prevent ICC. Women with a low educational level (OR = 6.6) or women who originated from Africa (OR = 6.5) were more likely to be unaware of Pap-test. Lack of Pap-test awareness was strongly associated with negative history for lifetime Pap-test (OR = 4.7). CONCLUSIONS: We showed that a large proportion of HIV-infected women are not aware that ICC could be prevented through Pap-test screening, and that lack of Pap-test screening is strongly associated with lack of awareness. The need for Pap-test counseling targeted to HIV-infected women clearly emerges from our findings.

Adult↗
PubMed2005

World Health Organization collaborative study to establish a replacement WHO international standard for hepatitis C virus RNA nucleic acid amplification technology assays.

BACKGROUND AND OBJECTIVES: A collaborative study was undertaken to establish a replacement for the current (1st) World Health Organization (WHO) hepatitis C virus (HCV) International Standard, 96/790. MATERIALS AND METHODS: Both the 1(st) International Standard and the replacement standard were prepared from the same starting material by diluting a high titre genotype 1a HCV isolate in pooled, human plasma. The only difference was that each standard was lyophilized in two, separate lyophilisation runs but under the same conditions. RESULTS: In the study to establish the 1st International Standard, no significant difference in potency was found between the material eventually designated as the 1st International Standard and that now selected as the 2nd International Standard. The present study also showed no significant differences between the materials stored at -20 degrees C and no evidence of degradation over 5 years. CONCLUSIONS: Material 96/798 was established as the 2nd HCV International Standard and assigned the same unitage as the 1st International Standard, i.e. 10(5) IU/ml (50,000 IU/vial).

DNA Primers↗
PubMed2005

A World Health Organization International Standard for hepatitis A virus RNA nucleic acid amplification technology assays.

BACKGROUND AND OBJECTIVES: Sixteen laboratories from 10 different countries participated in an international collaborative study to evaluate candidate materials as the first World Health Organization (WHO) International Standard for hepatitis A virus (HAV) RNA nucleic acid amplification technology (NAT) assays. MATERIALS AND METHODS: Five candidate materials were analysed in this study: materials AA and BB were lyophilized, while materials CC, DD and EE were liquid preparations. Samples were diluted in pooled plasma or in pooled cryo-poor plasma (sample EE). Serial dilutions of the candidate materials were tested by each laboratory in four independent assays and the results were analysed statistically. RESULTS: The mean log(10)'equivalents' per ml were 5.29 for sample AA, 5.07 for sample BB, 4.99 for sample CC, 5.40 for sample DD and 4.08 for sample EE. CONCLUSIONS: Based on the results of this study, sample AA was established as the first International Standard for HAV RNA NAT assays at the WHO Expert Committee on Biological Standardizaton (ECBS) meeting held in February 2003. The code number of this preparation is 00/560 and the potency, based on the study, is 100 000 International Units (IU)/ml.

Cooperative Behavior↗
PubMed2004

External quality assessment for the detection of blood-borne viruses in plasma by nucleic acid amplification technology: the first human immunodeficiency virus and hepatitis B virus studies (HIV EQA/1 and HBV EQA/1) and the fifth hepatitis C virus study (HCV EQA/5).

BACKGROUND AND OBJECTIVES: This External Quality Assessment (EQA) study was aimed at assessing the proficiency of blood centres and blood product manufacturers in detecting, by nucleic acid amplification technology (NAT), the possible contamination of plasma with hepatitis C virus (HCV), human immunodeficiency virus (HIV) and hepatitis B virus (HBV). MATERIALS AND METHODS: Three independent panels, one for each virus, were prepared at the Istituto Superiore di Sanità (ISS) by diluting the respective reference preparations. NAT methods used by the EQA participants included polymerase chain reaction (PCR) assays by Roche, transcription-mediated amplification (TMA) assays by Chiron and in-house PCR assays. RESULTS: Forty-three of the 45 participants (95.6%) in the HCV EQA/5 who used a validated method were consistently able to detect a nominal concentration of 100 IU/ml for all six major genotypes. In the case of the HIV EQA/1, all 35 participants detected the samples containing 1000 IU/ml HIV, while five (14.3%) did not identify the samples containing 100 IU/ml HIV. With respect to the HBV EQA/1, all 16 participants correctly identified the positive samples containing either 1000 IU/ml or 100 IU/ml HBV. No false-positive results were observed with any of the three panels. CONCLUSIONS: The HCV EQA/5 showed an improved proficiency of laboratories as compared with the HCV EQA/4. In fact, HCV genotypes 1, 2, 3 and 5 were correctly identified in 100% of the assays and genotypes 4 and 6 in 97.8% of the assays. While most of the participants in the HIV EQA/1 showed a good level of proficiency, an excellent performance was shown by all participants in the HBV EQA/1.

False Positive Reactions↗
PubMed2004

Hepatorenal syndrome.

PURPOSE: Discuss exhaustively the clinical aspects of hepatorenal syndrome (HRS), laboratory data, the progress made in understanding the pathogenesis, and treatment. DESIGN: The work is a result of the research conducted in the framework of the most important studies on HRS. RESULTS AND CONCLUSIONS: Functional renal failure (FRF) is the most severe manifestation of hepatorenal syndrome, and becomes manifest with a decreased renal perfusion along with oliguresis, reduced excretion of sodium, high urinary osmolarity, azotemia and creatinemia. Liver transplantation restores normal renal function in patients affected by HRS; this suggests the functional origin of the disease. Portal hypertension determines systemic arterial vasodilatation (peripheral vasodilatation theory), with non absolute but effective hypovolemia in terms of its ability to release high circulating levels of vasoactive substances (PG vasodilators, endotoxins, nitric oxide, calcitonin-GPP, glucagon and PAF). Following vasodilatation, a number of systems are triggered to restore peripheral resistance, such as the renin-angiotensin-aldosterone system, the sympathetic systems and the antidiuretic hormone. In some subjects, the activation of these hormones is sufficient to restore resistance and fill the dilated vascular bed, with the subsequent inactivation of the systems themselves. Conversely, in a subgroup of cirrhosis patients with severe portal hypertension, the activation of water retention and vasoconstrictive systems is not sufficient to restore an effective volemia. These subjects present hypotension, effective hypovolemia, high renin levels, high norepinephrine levels and high antidiuretic hormone levels. These substances cause in a sequence, at the renal level, water and sodium retention, progressive vasoconstriction, reduction of plasma flow and GF, initially countered by intrarenal defense mechanisms such as PG, prostacyclins and callicreins. The FRF also sets in because the kidney, in its context, produces determinant endogenous ischemia-inducing substances like tromboxanes, endothelines and leukotrienes. Kidney transplantation is the only treatment.

Albumins↗
PubMed2003

High proficiency in detecting the six major hepatitis C virus genotypes of laboratories involved in testing plasma by nucleic acid amplification technology.

Since the introduction of mandatory HCV RNA testing of plasma pools for fractionation by nucleic acid amplification technology, we have organised External Quality Assessment studies (EQAs) addressed to blood products manufacturers and blood centres. Here we report the results of a new EQA, the first one to include all six major HCV genotypes. The results, reported by laboratories worldwide, showed that genotypes 1, 2 and 3 were correctly identified in 100% of the tests, genotype 4 in 96.7% and genotypes 5 and 6 in 98.3% of the assays. As detection of all HCV genotypes is critical for laboratories involved in testing plasma for HCV, all six genotypes should continue to be included in the next EQA studies.

Blood Transfusion↗
PubMed2001

Hepatitis C virus testing of plasma pools by nucleic acid amplification technology: external quality assessment.

BACKGROUND AND OBJECTIVES: Since 1 July 1999, in accordance with European regulations, only batches of blood products obtained from plasma pools tested and found to be non-reactive for hepatitis C virus (HCV) RNA are being released. As monitoring the performance of manufacturers involved in plasma pool testing is important to ensure reliable amplification techniques, the Istituto Superiore di Sanità, as the Italian regulatory authority, organized an external quality assessment study. MATERIALS AND METHODS: A reference HCV RNA panel calibrated in international units (IU) was sent to each participant to be tested according to the validated procedure they routinely used in plasma pool testing. The panel consisted of 20 coded samples, four of which were obtained from a negative plasma pool. The remaining 16 samples, prepared by diluting the national reference preparation (ISS HCV RNA 0498), represented four half-log dilution series, each consisting of four samples containing 100, 32, 10 and 3.2 IU/ml of HCV RNA. RESULTS: The overall performance of the laboratories was very satisfactory. All laboratories correctly identified the negative samples. The 100- and 32-IU/ml samples were both detected in 98.4% of the assays, while the 10- and 3.2-IU/ml samples were detected in 73.4 and 50.0% of the assays, respectively. No substantial differences were observed between in-house procedures and commercial kits. CONCLUSION: This external quality assessment study showed that manufacturers of blood products have reached a high level of proficiency that fully complies with the European Pharmacopoeia requirements. This finding is reassuring in the context of the safety of blood products.

Blood Specimen Collection↗
PubMed2001

Prevalence of TT virus in healthy children and thalassemic pediatric and young adult patients.

BACKGROUND: The recently discovered TT virus (TTV) has been shown to be highly prevalent in patients with cryptogenetic chronic liver disease and fulminant hepatitis. To study the frequency of TTV and to evaluate the possible association with liver disease, 37 pediatric and young adult patients with thalassemia, and 36 healthy children were included in the study. The sera of 100 blood donors selected randomly in the same period were also tested for TTV DNA. METHODS: The TTV amplification by polymerase chain reaction (PCR) was performed using a first set of primers that recognize an internal sequence into N22 and a second set of primers amplifying a sequence within 5;NCR (5; noncoding region). RESULTS: The first set of primers revealed TTV DNA in 73% of thalassemic patients, in 8% of healthy children, and in 5% of healthy blood donors. With the second set of primers, the prevalence of TTV DNA was, respectively, 100% in thalassemic patients, 44.5% in healthy pediatric patients, and 87% in healthy blood donors. All individuals who tested positive for TTV by the first set of primers were also positive by the second primer set. The TTV infection seemed not to be the cause of altered transaminase levels. Sequencing of TTV clones from thalassemic patients showed the presence of different TTV variants in the same serum. CONCLUSION: The prevalence of TTV in polytransfused children is similar to that detected in blood donors. Moreover, TTV can be detected in healthy children of all ages. The presence of TTV seems to have no clinical significance.

Adolescent↗
PubMed2001

[In vivo apoptotic effect of alpha-2b interferon (IFN) on rat preneoplastic liver ].

In order to know whether IFN alpha prevents in vivo oncogenesis in the very-early-stage cancer cells, we evaluated the action of IFN alpha-2b on preneoplastic foci in rats. Animals were divided into six groups: subjected to an initiation-promotion model of cancer development (G1), treated with IFN alpha-2b during: a) initiation-promotion (G2), b) initiation (G3), promotion (G4); subjected only to an initiation stage (G5) and treated with IFN alpha-2b during this period (G6). The number and area of rGST P-positive foci were reduced and the Apoptotic index was increased in G2, 3 and 6. Bcl-2 and Bcl-XL protein levels were decreased in IFN alpha-2b-treated rats. Increased levels of mitochondrial Bax protein were observed in G2, 3 and 6. In conclusion, preneoplastic hepatocytes in the IFN alpha-2b-treated rats undergo programmed cell death as a result of a significant increase of Bax and its translocation to the mitochondria.

Animals↗
PubMed2000

Calibration of HCV working reagents for NAT assays against the HCV international standard. The Collaborative Study Group.

BACKGROUND AND OBJECTIVES: Five HCV RNA reference reagents, the Paul Ehrlich Institut (PEI) reference 75, the National Institute for Biological Standards and Control (NIBSC) reagent 96/586, the Central Laboratory of the Netherlands Red Cross Blood Transfusion Service (CLB) Pelispy HCV RNA run control S2001, the Istituto Superiore di Sanità (ISS) reagent 0498 and the CBER panel member No. 1, were calibrated against the WHO International Standard, 96/790. MATERIALS AND METHODS: The reference materials were calibrated in a collaborative study organised by NIBSC. Nineteen laboratories, using a range of qualitative and quantitative assays returned results. RESULTS: The concentrations of the reagents were: 25,000 IU/ml for the PEI material, 710 IU/ml for the NIBSC material 96/586, 1,000 IU/ml for the CLB material, 1,700 IU/ml for the ISS material 0498 and 250 IU/ml for the CBER panel member No. 1. CONCLUSIONS: The calibration of these five reference reagents for HCV RNA nucleic acid amplification technology (NAT) assays enables them to be used for standardisation and validation of assays. Such calibrants are essential for meeting the requirements of the European Medicinal Evaluation Agency (EMEA) for the testing of plasma pools and donations for HCV RNA for the release of blood products and the PEI requirements for the release testing of erythrocyte and thrombocyte concentrates.

Calibration↗
PubMed2000

Prevalence of TT viral DNA in italian blood donors with and without elevated serum ALT levels: molecular characterization of viral DNA isolates.

BACKGROUND AND OBJECTIVE: A novel non-enveloped DNA virus, called TT virus (TTV), has been reported to be associated with post-transfusion hepatitis of unknown etiology. Although its clinical role still remains obscure, its presence in blood donations might cause problems. It, therefore, appeared of interest to investigate TTV prevalence in voluntary blood donors. DESIGN AND METHODS: A total of 595 Italian blood donors with and without elevated serum alanine aminotransferase (ALT) levels were tested by polymerase chain reaction using two sets of semi-nested primers that amplify the well-known region in the N22 clone. The amplified products were then sequenced to assess the genotype by phylogenetic and restriction fragment length polymorphism analyses. RESULTS: The prevalence of TTV in blood donors was 5+/-1.9% (25 out of 500) with a 95% confidence limit. A similar prevalence was found in 95 selected blood donors with increased ALT levels. A viral load of 10(3)-10(4) viral DNA molecules/mL was found, thus indicating a rather narrow range of variability. A phylogenetic tree built up on the basis of 210 base sequences of ORF1 allowed isolates to be classified into 2 groups corresponding, at least, to two of the putatives TTV genotypes, group 1 and group 2 of Okamoto's classification. A similar classification was also obtained by site restriction enzyme analysis. INTERPRETATION AND CONCLUSIONS: The results show that TTV infection is present among Italian blood donors. No significant difference in prevalence of TTV infection was found between patients with normal and increased ALT, making the association between TTV infection and human hepatitis questionable.

Adolescent↗
PubMed1999

Adaptive hepatic changes in mild stenosis of the common bile duct in the rat.

Adaptive hepatic changes were investigated in rats with mild stenosis of the common bile duct and in sham-operated controls. The studies were performed 24 h and 7-12 days postoperatively. A continuous intravenous infusion of taurocholic acid at stepwise-increasing rates was performed to explore the responses to bile acid effects. During the infusion, bile flow and the outputs of bile acids, phospholipids, cholesterol, alkaline phosphatase and gamma glutamyl transpeptidase were studied. At the end of the infusion, hepatic morphometric measurements were performed. In other experimental sets, biliary excretions of horseradish peroxidase, a marker of microtubule-dependent vesicular transport in the hepatocyte, and sulphobromophthalein, a well-known organic anion model, were studied. In other rats, bile acid pool size and composition were determined by depletion of bile. The results in rats with mild stenosis maintained for 24 h showed a greater susceptibility to the toxicity of taurocholic acid, as revealed by the abrupt decrement in bile flow at high rates of infusion, and increased outputs of phospholipids and canalicular enzymes. Conversely, rats with mild stenosis maintained for 7-12 days showed decreased bile acid maximum secretory rate and biliary outputs of phospholipids and canalicular enzymes, as well as hepatocyte hypertrophy. These findings may explain the limited hepatic and systemic repercussion of experimental mild stenosis of the common bile duct and help us to understand the early stages of constriction of the common bile duct in man.

Adaptation, Physiological↗
PubMed1999

Prevalence of TT virus in plasma pools and blood products.

A high prevalence of TT virus (TTV), a novel virus recently identified in the serum of a patient with post-transfusion hepatitis of unknown aetiology, has been reported in blood donors worldwide. We investigated the presence of TTV DNA in several lots of blood products and in the corresponding plasma pools. In the process, we determined, from three sets of primers, the one which was most efficient in detecting the viral nucleic acid. This set amplifies the region closest to the 3'-end of the TTV genome which was proved, by sequence analysis, to be more conserved than the other two regions. Whereas all 10 intravenous immunoglobulin and 21 albumin batches were TTV negative, 4/5 factor VIII concentrates and 4/10 intramuscular immunoglobulin batches were TTV positive. A high prevalence of TTV DNA (70%) was found in the plasma pools that were collected from four different countries. These results confirm the worldwide distribution of this virus and show that TTV is removed with a varying efficiency during the manufacture of blood products.

Blood↗