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A Gentile

Publications and source records attributed to A Gentile.

At least 37 records · Page 2Linked to original sources
PubMed2001

A gene trap vector system for identifying transcriptionally responsive genes.

We present a method for fast and efficient trapping of genes whose transcription is regulated by exogenous stimuli. We constructed a promoterless retroviral vector transducing a green fluorescent protein-nitroreductase (GFNR) fusion protein downstream from a splice acceptor site. Flow cytometric analysis of the infected population allows identification and sorting of cells in which the trap is integrated downstream from an active promoter. Conversely, the nitroreductase (NTR) moiety allows pharmacological selection against constitutive GFNR expression. Using hepatocyte growth factor (HGF) stimulation of liver cells combined with either positive or negative selection, we recovered cell populations carrying traps in induced or suppressed genes, respectively. Several distinct responsive clones were isolated, and regulated expression of the trapped gene was confirmed at the RNA level. Positive and negative selection can be calibrated to recover traps in genes showing different levels of basal expression or transcriptional regulation. The flexibility and efficiency of the GFNR-based trap screening procedure make it suitable for wide surveys of transcriptionally regulated genes.

Blotting, Northern↗
PubMed2001

Helicobacter heilmannii gastritis: a histological and immunohistochemical trait.

AIM: Biopsies of the gastric antrum were reviewed over a period of 10 years to determine the prevalence of Helicobacter heilmannii in symptomatic subjects from this geographical area and to relate its presence to distinctive histopathological and immunohistochemical features. METHODS: Biopsies from 7926 symptomatic patients were reviewed. Ten serial sections were stained with haematoxylin and eosin for conventional histology. Another 10 sections were stained with the Gram method for spiral bacteria. When H heilmannii was suspected, 10 additional serial sections were stained with methylene blue to obtain homogeneous colouring. An equal number of sections from patients affected by isolated H heilmannii or H pylori gastritis were analysed by immunohistochemistry to evaluate lymphoid aggregate/mucosal lymphocyte clonality (CD20 and CD3) and tumour necrosis factor alpha (TNF-alpha) in stromal cells. RESULTS: The prevalence of H heilmannii was 0.1% (eight of 7926), whereas H pylori was present in 60.7% of patients (4813 of 7926). In two of the eight H heilmannii positive patients both helicobacters were found. In all subjects infected by H heilmannii only, distinctive histology (lymphocyte exudation into gastric foveolae) was seen. Lymphoid aggregates, chronic mucosal inflammation with patchy activity, and the absence of epithelial mucus depletion were regular features of H heilmannii gastritis. Immunohistochemistry did not reveal different lymphocyte clonal patterns between H pylori and H heilmannii gastritis: CD20 positive cells were predominant in the centre of aggregates and mucosal infiltrates, whereas CD3 positive cells were prevalent at the periphery of follicles. Only H pylori gastritis showed a significant increase in TNF-alpha positive stromal cells. CONCLUSION: These data suggest that an unusual lymphocyte reaction, with the tendency to invade the foveolar lumen, is a distinctive histopathological aspect of H heilmannii chronic gastritis, although further studies in a larger series are necessary to confirm this fact. Nevertheless, lymphocyte clones do not differ qualitatively from those found in H pylori infection. Moreover, compared with H heilmannii, H pylori provokes a more intense release of TNF-alpha, suggesting that different inflammatory responses exist to these two organisms.

Adolescent↗
PubMed2001

[Primary lymphoma of the gastrointestinal tract].

BACKGROUND: A retrospective analysis of 12 years' experience (1987-1999), concerning gastro-intestinal lymphomas (LNH-GI) has been performed, to offer a contribution for the identification of the diagnostic and prognostic criteria. METHODS: During this period, 11 cases (9 male and 2 female) have been treated: 8 with gastric localization and 3 with intestinal localization, with age ranging between 12 and 78 years. Most of the analyzed cases (5 cases out of 8 with gastric localization and all the cases with intestinal localization) underwent surgical treatment without a sure understanding of the nature of lymphoma. Clinical observation showed forms in an advanced state of local development. RESULTS: However, the low specifity of available diagnostic tools and the therapeutic delay are factors that seems do not influence the prognosis, as well as the stage of the disease determined with traditional classification methods. The aspect that seems to be crucial for the prognosis of the disease is the histotype (5 low grade cases free of desease from 36 months to 10 years, vs 4 high grade cases died between 46 days and 40 months after the surgical treatment). CONCLUSIONS: Some interesting considerations arise from the analysis of the diagnostic procedure and from the method of treatment: the specifity and precocity of the diagnosis could be improved by a large use of endoscopic ultrasonography that allow to obtain deep biopsy; the identification of histotype before surgical treatment can address and modulate the therapeutic strategy eliminating the over treatment for L.G. forms.

Adolescent↗
PubMed2001

A nodular pulmonary lesion due to Linguatula serrata in an HIV-positive man.

A coin-shaped pulmonary lesion was accidentally detected in a 42-year-old, HIV-seropositive man residing in Bari (Apulia, Southern Italy) during a routine X-ray examination. A lung cancer was suspected, obliging physicians to investigate surgically. After thoracotomy a lung nodule, 1.8 cm in diameter, was excised and submitted for histological examination. Histological analysis revealed a nodular infarctual lesion containing a larva of Pentastomida. Despite the poor state of preservation of the parasite it was possible to recognise some morphological characteristics which enabled the parasite to be identified as Linguatula serrata (Pentastomida, Porocephalida). This is the first case reported in Europe in the lung in a living man due to this parasite, the few others occurring in autopsy reports. No evident correlations were found in the present case between HIV-seropositivity and the development of the parasitosis. The importance of lung nodules caused by metazoan invertebrates is emphasised: even though they are rare in man, they are regularly mistaken for cancer at X-ray examination.

Adult↗
PubMed2000

Characterization of peroxisomal 3-hydroxy-3-methylglutaryl coenzyme A reductase in UT2 cells: sterol biosynthesis, phosphorylation, degradation, and statin inhibition.

We have previously identified a CHO cell line (UT2 cells) that expresses only one 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase protein which is localized exclusively in peroxisomes [Engfelt, H.W., Shackelford, J.E., Aboushadi, N., Jessani, N., Masuda, K., Paton, V.G., Keller, G.A., and Krisans, S.K. (1997) J. Biol. Chem. 272, 24579-24587]. In this study, we utilized the UT2 cells to determine the properties of the peroxisomal reductase independent of the endoplasmic reticulum (ER) HMG-CoA reductase. We demonstrated major differences between the two proteins. The peroxisomal reductase is not the rate-limiting enzyme for cholesterol biosynthesis in UT2 cells. The peroxisomal reductase protein is not phosphorylated, and its activity is not altered in the presence of inhibitors of cellular phosphatases. Its rate of degradation is not accelerated in response to mevalonate. Finally, the degradation process is not blocked by N-acetyl-Leu-Leu-norleucinal (ALLN). Furthermore, the peroxisomal HMG-CoA reductase is significantly more resistant to inhibition by statins. Taken together, the data support the conclusion that the peroxisomal reductase is functionally and structurally different from the ER HMG-CoA reductase.

Acetic Acid↗
PubMed1999

Phase I/II dose finding study of paclitaxel and carboplatin in advanced non-small cell lung cancer.

INTRODUCTION: This phase I study was designed to establish the maximum tolerated dose (MTD) of the carboplatin paclitaxel combination, given without routine growth factor support to previously untreated patients with stage IIIB and IV non-small cell lung cancer. PATIENTS AND METHODS: Fifty patients (one stage IIIa, 31 stage IIIb and 18 stage IV) were sequentially assigned to one of 14 treatment groups in which paclitaxel and carboplatin were administered in doses ranging from 130 to 235 mg/m2 and from 230 to 375 mg/m2 , respectively. Paclitaxel was administered as a 3-h intravenous infusion using non-polyvinylchloride tubing and connectors. The carboplatin infusion, over 30 min, was administered at the completion of the paclitaxel infusion. RESULTS: The MTD for the combination has been reached at 235 mg/m2 of paclitaxel and at 375 mg/m2 of carboplatin. The combination shows a good safety profile with very few and brief episodes of neutropenia without any infectious episodes. At the doses tested thrombocytopenia did not occur at all. Among 47 assessable patients there was one complete response and 17 partial responses for an overall response rate of 38%. There has been a tendency to a dose-response relationship for the combination with only six partial responses (27%) reported in 22 patients who received paclitaxel at doses < or = 195 mg/m2 and carboplatin at doses < 350 mg/m2 and 12 partial responses in 25 patients (48%) receiving paclitaxel > 195 mg/m2 and carboplatin > or = 350 mg/m2, respectively. The median event-free survival time is 33 weeks (range, 4-156 +). With a minimum follow up duration of 57 weeks the median overall survival time is 51.81 weeks (range, 7-162 +) and the 1-year survival rate is 49%. CONCLUSION: In advanced NSCLC the carboplatin-paclitaxel combination can be safely administered at the doses of 375 and 225 mg/m2 every 4 weeks, it appears to be active and well tolerated.

Adolescent↗
PubMed1999

Effects of simvastatin and pravastatin on hyperlipidemia and cyclosporin blood levels in renal transplant recipients.

Thirty-one renal transplant recipients, submitted to treatment with cyclosporin in association with other immunosuppressive agents, were also treated for 9 months with two hydroxymethylglutaryl coenzyme A reductase inhibitors, simvastatin (10 mg/day) or pravastatin (20 mg/day), for concomitant hypercholesterolemia and hypertriglyceridemia. Both drugs significantly decreased total cholesterol and triglyceride serum levels, but they did not modify whole-blood trough concentrations of polyclonal and monoclonal cyclosporin or polyclonal/monoclonal cyclosporin ratio. No alterations of the clinical and laboratory parameters investigated were found. The results of this study show the efficacy and safety of hydroxymethylglutaryl coenzyme A reductase inhibitors in the treatment of hyperlipidemia in kidney transplant patients.

Adult↗
PubMed1999

[Doppler echography in the intraoperative assessment of the liver circulation: an experimental study in swine].

In this experimental study the authors report an experience in the evaluation of hepatic blood flow with intraoperative echo-Doppler during orthotopic liver transplantation and side-to-side or end-to-side portacaval shunt. Doppler ultrasonography studied the flow of portal vein, hepatic artery and inferior vena cava before the recipient hepatectomy, and after reperfusion during liver grafting. Furthermore echo-Doppler of the portal system was performed to confirm portacaval shunt efficacy. Usually intraoperative Doppler ultrasonography may give informations about the patency of the shunt and regarding the development of early hepatic artery thrombosis during liver transplantation, but often unclear is the exact evaluation of the velocity of the blood flow through the liver. Further experimental studies and clinical evaluations need to find safe parameters and markers of vascular alteration using this superior diagnostic procedure.

Animals↗
PubMed1999

[Study of the Ki-67 antibody immunolabeling of renal adenocarcinomas with or without renal vein thrombosis].

OBJECTIVES: The objective of this study was to compare the proliferation index (immunolabelling by monoclonal antibody Ki67 - MIB-1) of renal cell carcinomas as a function of the presence or absence of renal vein thrombus. Analysis of the numbers of Ki67-positive nuclei can be used to assess the degree of aggressiveness of the cell populations of these various carcinomas (tumour without thrombus, tumour with thrombus and neoplastic thrombus). METHODS: Twenty three renal cell carcinomas with renal vein thrombus were matched for Furhman grade (1st degree), tumour volume (2nd degree) and the patient's age (3rd degree) with 23 renal cell carcinomas not presenting any vascular embolus on histology. Monoclonal antibody MIB-1 immunolabelling was performed on 69 paraffin-embedded specimens: 23 tumours with thrombosis, the 23 corresponding neoplastic thrombi and 23 tumours without vascular embolus. RESULTS: A correlation between Furhman grade and the percentage of immunolabelled nuclei was observed (mean: 2.67% for low-grade tumours and 14.34% for high-grade tumours). No labelling difference was observed between the two populations of primary tumours (with thrombus/without embolus). Primary tumours presented significantly weaker Ki67 labelling than their corresponding neoplastic thrombus (mean of 2.47% versus 10.3%, p < 0.01). CONCLUSION: This study shows that there is no difference of the proliferation index between tumours with neoplastic venous thrombus and those with no histological vascular embolus. However, a difference of proliferation index was observed between the primary tumour and its corresponding thrombus, which presented a statistically higher immunolabelling. This finding suggests that the thrombus possesses more dividing cells than the primary tumour, i.e. has a shorter doubling time.

Adenocarcinoma↗
PubMed1999

Immunohistochemical detection of Helicobacter pylori vacuolating cytotoxin in the hepatocytes of patients with isolated hypertransaminasaemia.

BACKGROUND AND AIM: Even if different Helicobacter species can colonise animal livers and induce hepatitis, there is no evidence that Helicobacter pylori can damage this organ and only a potential capacity of cytotoxic strains to increase transaminases in humans has been suggested. We have, therefore, carried out an immunohistochemical study on vacuolating cytotoxin in the hepatocytes of subjects with isolated hypertransaminasaemia. PATIENTS, METHODS AND RESULTS: Five male patients with isolated hypertransaminasaemia without signs of known causes of liver diseases were studied. Endoscopy demonstrated diffuse mucosal hyperaemia in 3 patients and duodenal ulcer in one. Histology revealed active chronic pangastritis in all. Helicobacter pylori was assessed by histology and culture and its cytotoxity, demonstrated by positive immunoblotting for both anti-CagA and VacA. Percutaneous liver biopsy showed minimal changes. Hepatic and gastric sections were tested either with autologous serum and rabbit antibody to VacA toxin. Immune reaction was revealed by immunoperoxidase. Both autologous sera and anti-VacA toxin antibody showed a reaction with a similar pattern which involved 60% of hepatocytes. Anti-VacA toxin showed a reaction to gastric epithelial cells and autologous sera to parietal cells in 4/5 patients. All patients received triple therapy and eradication of Helicobacter pylori was assessed by urea breath test. Serum transaminase levels 3 months after eradication, are still abnormal. CONCLUSIONS: Our immunohistochemical findings suggest that vacuolating cytotoxin could reach the hepatocytes of patients suffering from both isolated hypertransaminasaemia and infection by cytotoxic strains of Helicobacter pylori. Nevertheless, a clear relationship between these two condition remains uncertain.

Adult↗
PubMed1998

Weekly paclitaxel-cisplatin administration with G-CSF support in advanced breast cancer. A phase II study.

PURPOSE: In a previous phase I study we found the MTDs of paclitaxel and cisplatin when given together weekly, with or without G-CSF support, in patients with advanced solid tumors. The present study was conducted to define the toxicity and efficacy of this regimen, when used with G-CSF support, in chemotherapy-naive or pretreated patients with advanced breast cancer, and to compare the antiproliferative activity of paclitaxel-cisplatin and paclitaxel-doxorubicin combinations on two human breast cancer cell lines. METHODS: Patients with metastatic breast cancer received weekly paclitaxel (as a 3-hour i.v. infusion) at the dose of 85 mg/m2 (75 mg/m2 in pretreated women) followed by cisplatin (40 mg/m2) for a minimum of 6 weeks. An additional 6 weekly cycles were delivered in patients showing absence of documented disease progression after the first 6 weeks. After the 12th cycle only patients who had shown a substantial tumor shrinkage received 6 further cycles. G-CSF 5 microg/kg was also given, SC on days 3 to 5 of each week, for the whole duration of chemotherapy. The combination of paclitaxel with cisplatin or doxorubicin was also tested in vitro on two breast cancer cell lines (MCF-7 and MDAMB-231). RESULTS: Forty-three women with metastatic breast cancer entered this trial between June 1995 and January 1997. Twenty-seven patients were previously untreated for their metastatic disease (but 23 had previously received adjuvant chemotherapy). The dominant site of disease involvement was visceral in 23, bone in 13, and soft tissues in 7 patients. Seven complete and 15 partial responses were observed in unpretreated patients, while no complete and 6 partial responses were achieved in the pretreated population. The overall response rate, assessed on an 'intent to treat' basis, was 81% (26% CRs) in patients unpretreated for metastatic disease and 37% in those who had received one or more previous chemotherapy regimens. Eighteen responder patients had previously received anthracyclines either as adjuvant chemotherapy (12) or in the treatment of metastatic disease (6). At a median potential follow-up of 12 (range, 3-21) months, 14/27 unpretreated and 12/16 pretreated patients had shown disease progression. The median time to treatment failure was 13 and 7 months, respectively, in the 2 subgroups. The 1-year survival probability was 95% in unpretreated patients. The treatment showed a moderate toxicity in both subgroups of patients. Both hematological toxicity and peripheral neuropathy occurred more frequently in pretreated patients. Treatment-related deaths did not occur, and severe myelosuppression was observed only in pretreated patients with massive liver involvement. Delays in chemotherapy administration were very uncommon, especially during the first 6 treatment cycles, and the average actually delivered dose intensity exceeded 90% in unpretreated patients. The in vitro data on MCF-7 and MDA-MB-231 human breast cancer cell lines showed that exposure to the combination of cisplatin and paclitaxel produced a tumor cell killing similar to that achievable with equivalent concentrations of doxorubicin and paclitaxel. CONCLUSIONS: Weekly paclitaxel and cisplatin with G-CSF support is an active and particularly well tolerated treatment for patients with either unpretreated or pretreated metastatic breast cancer. This approach seems quite effective also in patients relapsing after anthracycline-based adjuvant chemotherapy. In view of the negligible hematological toxicity associated with this regimen, further clinical trials testing the addition of non cross-resistant drugs to this combination should be performed.

Adult↗
PubMed1998

The combination of paclitaxel and carboplatin as first-line chemotherapy in patients with stage III and stage IV ovarian cancer: a phase I-II study.

The combination of paclitaxel 135 mg/m2 (24-hour infusion) and cisplatin 75 mg/m2 is now considered the standard treatment in first-line chemotherapy for stage III suboptimally debulked and stage IV ovarian cancer. Interest is focused on the possibility of evaluating the combination of paclitaxel with carboplatin, because it was found to be less nefrotoxic and less neurotoxic than cisplatin. This study seeks to determine the maximum tolerated dose and to assess the antitumor activity of the combination of a 3-hour paclitaxel infusion followed by carboplatin. Thirty-three chemotherapy-naive patients with stage III-IV epithelial ovarian cancer entered this open, nonrandomized dose-finding study. The first dose level investigated was paclitaxel 125 mg/m2 and carboplatin 250 mg/m2: the dose level progression was performed by alternatively increasing paclitaxel 25 mg/m2 and carboplatin 50 mg/m2. Cycles were repeated every 28 days. At least three patients were treated at each dose level. Overall, 233 and 224 cycles, respectively, are evaluable for nonhematologic and hematologic toxicity. Dose-limiting toxicities (febrile neutropenia and severe fatigue) were observed in two of six patients at level VIII (paclitaxel 225 mg/m2 and carboplatin 400 mg/m2) and therefore the previous dose-level (paclitaxel 200 mg/m2 and carboplatin 400 mg/m2) was considered as the maximum tolerated dose. Neutropenia (grade 3-4 in 63% of cycles), neurotoxicity (grade 2 in 37.5% and grade 3 in 9% of patients), arthromyalgias (grade 2 in 53% of patients and grade 3 in 3% of patients), and grade 3 alopecia were the most common toxicities observed. The incidence of thrombocytopenia was low (grade 3 in 4% of cycles) and no renal toxicity was observed. An objective remission was documented in 74% of 31 evaluated patients, including eight complete remissions (26%) confirmed by second-look surgery. The combination of paclitaxel 200 mg/m2 3-hour infusion followed by carboplatin 400 mg/m2 (30-minute infusion) is a safe and active regimen as first-line chemotherapy for advanced ovarian cancer.

Adult↗
PubMed1998

Gastric and intestinal ethanol toxicity in the rat. Effect on glutathione level and role of alcohol and acetaldehyde metabolisms.

BACKGROUND/AIMS: This study investigated the dose- and time-dependent effect of ethanol on gastric and intestinal glutathione and protein oxidative state in the rat. METHODS: Rats received 1 or 4 g/kg of 25% ethanol solution orally or isocaloric glucose. Some rats received diethylmaleate, cimetidine or cyanamide before ethanol (1 g/kg). Glutathione, carbonyl proteins and histological damage were evaluated in the gastric and intestinal mucosa 6 hours after treatment. RESULTS: An increase in glutathione was observed 2 to 6 hours after 1 g/kg of ethanol both in the gastric and intestinal mucosa, whereas 4 g/kg decreased glutathione. The rise in glutathione after ethanol was associated with increased levels of its oxidized form; however, the total/oxidized ratio was significantly decreased only in the intestinal tract. Diethylmaleate depleted mucosal glutathione, while the subsequent ingestion of ethanol increased it. Unlike stomach, intestine showed a significant increase in carbonyl proteins and marked histological lesions after ethanol ingestion. Cimetidine and cyanamide inhibited by 50% the activity of alcohol dehydrogenase and by 80% aldehyde dehydrogenase, respectively, in the gastric and intestinal mucosa. Cyanamide significantly enhanced ethanol-induced protein oxidation and mucosal injury in the stomach. No such effect was observed in the intestine. CONCLUSIONS: The increase of glutathione after ingestion of low amounts of ethanol appears to be an adaptive mechanism against ethanol toxicity. Depletion of glutathione increased protein oxidation and the extent of histological damage in ethanol-treated rats. At gastric level, the effects of ethanol are exaggerated by the inhibition of acetaldehyde metabolism; while intestinal damages appear to be ascribed to ethanol itself.

Acetaldehyde↗
PubMed1998

[Systemic effects of ruminal acidosis following ruminal drinking in dairy calves. A retrospective analysis of 293 cases].

In a retrospective study the data of 293 young calves (age upon admission less than four weeks) with evidence of ruminal drinking (rumen pH < 6.0) were analyzed for possible associations between ruminal acidosis and various parameters of systemic acid-base metabolism (blood pH, blood levels of HCO3- and L-lactate, as well as anion gap). On the basis of the degree of ruminal acidosis (pH < 5.0/ > or = 5.0) and evidence of diarrhea, the animals were assigned to one of four groups. The results indicate that severe ruminal acidosis leads to disturbances of systemic acid-base metabolism in young calves, too. With additional diarrhea, those disturbances can be complex.

Acid-Base Equilibrium↗
PubMed1997

Liver inflammation and acute respiratory distress syndrome in a patient receiving hepatitis B vaccine: a possible relationship?

We describe a patient in whom clinical evidence of liver and lung dysfunction developed after he received the second dose of recombinant hepatitis B vaccine, despite no serologic evidence of viral hepatitis. However, liver biopsy specimens demonstrated both surface antigens and core antigens, possibly indicating silent hepatitis B virus infection. A search for an infective etiology for the patient's subsequent clinical deterioration in lung function did not yield pathogens: postmortem examination revealed evidence of immune complex-mediated organ injury in the liver, lungs, and kidneys.

Antigen-Antibody Complex↗