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C Rossi

Publications and source records attributed to C Rossi.

At least 73 records · Page 4Linked to original sources
PubMed2001

Solution structure of hyaluronic acid oligomers by experimental and theoretical NMR, and molecular dynamics simulation.

The conformational properties of hyaluronic acid (HA) oligomers in aqueous solution were investigated by combining high-resolution NMR experimental results, theoretical simulation of NMR two-dimensional (2D) spectra by Complete Relaxation Matrix Analysis (CORMA), and molecular dynamics calculations. New experimental findings recorded for the tetra- and hexasaccharides enabled the stiffness of the HA and its viscoelastic properties to be interpreted. In particular, rotating frame nuclear Overhauser effect spectroscopy spectra provided new information about the arrangement of the glycosidic linkage. From (13)C NMR relaxation the rotational correlation time (tau(c)) were determined. The tau(c) were employed in the calculation of geometrical constraints, by using the MARDIGRAS algorithm. Restrained simulated annealing and 1 ns of unrestrained molecular dynamic simulations were performed on the hexasaccharide in a box of 1215 water molecules. The beta(1 --> 3) and beta(1 --> 4) glycosidic links were found to be rigid. The lack of rotational degree of freedom is due to direct and/or water-mediated interresidue hydrogen bonding. Both single or tandem water bridges were found between carboxylate group and N-acetil group. The carboxylate group of glucuronic acid is not involved in a direct link with the amide group of N-acetyl glucosamine and this facilitated bonding between the residue and the water molecules.

Biopolymers↗
PubMed2001

Laminin alpha2 chain (merosin M chain) distribution and VEGF, FGF(2), and TGFbeta1 gene expression in angiogenesis of supraglottic, lung, and breast carcinomas.

The prognostic significance of vessel quantification in human solid tumours is still debated, due to the presence of multiple factors modulating neoangiogenesis and the invasiveness of neoplastic cells. This study examined ten supraglottic squamous carcinomas, ten non-small cell lung carcinomas (three squamous, five bronchioloalveolar, two adenocarcinomas), and nine classic (NOS) invasive ductal breast carcinomas. The properties studied in these tumours were vascularity; the immunohistochemical distribution of adhesion molecules such as alpha2beta1, alpha3beta1, alpha4beta1, alpha5beta1, alpha6beta4, and ICAM-1 in endothelial cells; extracellular matrix proteins (ECMPs) and laminin alpha2 chain (merosin M chain) in basal membranes of vessels; and gene expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGF2), and transforming growth factor beta1 (TGFbeta1), by in situ hybridization. Independently of tumour type and vascularity, laminin alpha2 chain expression was observed in the basal membranes of a limited proportion of vessels. In vitro experiments demonstrated laminin alpha2 chain expression mainly in early endothelial cell cultures, suggesting that laminin alpha2 chain expression in vivo can be considered a marker of early angiogenesis. Stromal and parenchymal vascularity was associated with laminin alpha2 chain expression in supraglottic carcinomas, whereas in the other tumours, laminin alpha2 chain-positive vessels were observed only in the stroma. In supraglottic carcinomas, VEGF-positive cells were mainly represented by neoplastic cells, whereas in the other tumours, the great majority of VEGF-positive cells were macrophages and fibroblasts. FGF2- and TGFbeta1-positive cells were macrophages and fibroblasts in all tumours. These observations suggest that in addition to the quantification and distribution of vessels, evaluation of their maturation may contribute to a better understanding of the role of angiogenesis in the growth and spread potential of solid tumours. In this regard, in supraglottic carcinomas, parenchymal angiogenesis seems to be regulated mainly by neoplastic cells, which may help to explain their high metastatic potential; in solid tumours of different histogenesis, different cells might be responsible for modulating tumour angiogenesis.

Aged↗
PubMed2001

Urban airborne particulate: genotoxicity evaluation of different size fractions by mutagenesis tests on microorganisms and comet assay.

The genotoxic effects of different size fractions of airborne particulate (Total, PM10 and PM25), extracted with acetone or toluene, were evaluated by: the Ames plate test (TA98 and TA100 strains, w/o S9), gene conversion and reversion (w/o endogenous metabolic activation) in the Saccharomyces cerevisiae D7 strain, and the comet assay on human leukocytes. The data on human leukocytes confirm the sensitivity of the comet assay and its applicability to assess genotoxicity in environmental samples. The PM2.5 fraction of airborne particulate generally shows the highest concentration of DNA-damaging compounds. Genotoxic response, in all the test systems applied, is highly dependent on extraction solvent used. Acetone seems to extract compounds with more similar genotoxic responses in the three test systems used than toluene extracts. Toluene appears to extract air pollutants genotoxic on yeast and leukocytes but is mainly cytotoxic on Salmonella.

Acetone↗
PubMed2001

Microbiological and densitometric TLC analyses for peptides in liposomes.

Quantitative determination of Leucinostatins and/or of similar peptides, such as Peptaibols, is sometimes quite difficult to perform especially when they are entrapped in vectors, i.e. liposomes, whose components display UV absorbances that may obscure those of the active principle. Therefore, in these cases, it is useful to find alternative ways, especially when high pressure liquid chromatography (HPLC) is difficult to perform or needs long procedure times. In the present paper, the use of microbiological and densitometric methods for quantitative analysis of Leucinostatin A (Leu-A) are described and the results compared with those from HPLC analyses. The use of microbiological and densitometric assays, furnished results comparable with those obtained by HPLC. Of the two methods used, the microbiological procedure appeared to be less accurate and precise.

Chromatography, Thin Layer↗
PubMed2001

Vascular endothelial growth factor expression, S-phase fraction and thymidylate synthase quantitation in node-positive colon cancer: relationships with tumor recurrence and resistance to adjuvant chemotherapy.

BACKGROUND: The behaviour of colorectal carcinomas may depend on molecular properties of tumors. In node-positive colon cancer, we assessed the S-phase fraction (SPF) index, the vascular endothelial growth factor (VEGF) expression and the TS levels. The combined analysis of SPF/VEGF was studied for predictivity of recurrent disease, the TS quantitation was related to the efficacy of fluorouracil-based adjuvant chemotherapy. PATIENTS AND METHODS: Consecutive patients with surgically-resected, node-positive colon cancer were studied. Flow cytometry for the SPF and immunohistochemistries for the TS and the VEGF expression were carried out on the primary tumor. Recurrences had to be proven by biopsy or surgery, and they were categorized as early, if occurred within 12 months after surgery, or late if occured 13 months or more. RESULTS: Of 150 evaluable patients, 100 had received fluorouracil-based adjuvant chemotherapy and 50 control patients were untreated. The combined analysis of the VEGF and the SPF showed a strong association between the two markers; 48 patients (32%) had high SPF/VEGF positive tumors and 69 patients (46%) had low SPF/VEGF negative tumors (P < 0.0001). The majority of disease-free patients (73.4%) showed VEGF negative/low SPF tumors (P < 0.0001). Early recurrences occurred more frequently in patients with VEGF positive/high SPF tumors (P < 0.001). In the 100 patients treated with adjuvant chemotherapy, 86% of relapsed patients had TS overexpressing tumors and 69% of disease-free patients had TS negative tumors (P < 0.001). Also, early recurrences occurred more frequently in TS overexpressing tumors (P < 0.0001). CONCLUSIONS: Evidence is supported that node-positive colon cancer constitutes a heterogenous disease. Patients with VEGF positive/high SPF tumors showed an unfavourable outcome compared to patients with VEGF negative/low SPF tumors. The efficacy of fluorouracil-based adjuvant chemotherapy may depend on the TS status.

Adult↗
PubMed2001

Congenital giant megaureter: first neonatal case.

The authors report the first neonatal presentation of a congenital giant megaureter (CGM), a very rare unilateral urinary anomaly, which is defined as "a ureter whose lumen is congenitally, focally and segmentally dilated to more than 10 times the normal diameter, in presence of normal bladder volume and function." The definition of CGM is purely descriptive; it can be secondary to several different diseases, and in the series of 21 CGM (12 in duplex system) reported by Chen-Ju Huang, the morphology of the distal ureter varied from a near normal caliber to a ureteral stenosis, a ureterocele or a complete ureteral atresia. J Pediatr Surg 36:944-945.

Abnormalities, Multiple↗
PubMed2001

Subjective health status assessment: evaluation of the Italian version of the SF-12 Health Survey. Results from the MiOS Project.

BACKGROUND: SF-12 is a generic short form health survey, developed in the USA from the original SF-36. It produces two summary measures evaluating physical and mental self-perceived health that are interchangeable with those from the SF-36. SF-12 has been successfully tested in nine Western European countries on large samples of the general population, where it has proved its brevity, comprehensiveness, reliability, validity and cross-cultural applicability. The present analysis directly assesses the SF-12 for the first time in various Italian settings, including the general population and specific patient groups. METHODS: Data for this report were collected from five different samples; in four of them the SF-12 was used as a 'stand-alone' instrument, while in the other one (used as the reference) it was embedded in the SF-36. Descriptive statistics, Spearman's correlation coefficients, confirmatory factor analysis, ordinal uni- and multi-variate least squares regression model and covariance analysis were used to evaluate the summary measures in each sample, and across relevant subgroups. Studies were ordered according to the expected deviance, from the 'normal' health status of the reference group to the sample with the expected highest level of illness. RESULTS: Overall, more than 11,000 subjects were evaluated. Response rates ranged from 63 to 100%, while missing items accounted only for 0.2-8.2% of all items. Uni- and multi-variate analyses showed a positive association between both physical component summary (PCS) and mental component summary (MCS) scores and their respective items in all examined samples. MCS scores were fairly similar across all samples, with the only exception being patients recently discharged from hospital, whose subjective mental health perception was higher than expected and the highest of all (52.2). Finally, we found a substantial impact of ageing on physical health perception, while the MCS was shown to be less sensitive to the age effect. CONCLUSIONS: This analysis shows that the SF-12 has good validity, while some issues related to its most appropriate mode of administration and target groups might require further attention.

Adolescent↗
PubMed2001

alpha-Blockade improves symptoms suggestive of bladder outlet obstruction but fails to relieve it.

PURPOSE: We investigated the effect of the alpha-blockers alfuzosin, terazosin and tamsulosin on urodynamic parameters after 6 months of therapy. MATERIALS AND METHODS: Between February 1992 and June 1998, 163 patients with lower urinary tract symptoms suggestive of bladder outlet obstruction were treated with alfuzosin (60), terazosin (66) and tamsulosin (37). Patients were evaluated with urodynamic studies, including pressure flow analysis, before treatment and after 6 months of therapy. Initially, all patients were also assessed by the International Prostate Symptom Score questionnaire and measurement of urinary flow rate. RESULTS: The majority of patients had no clear improvement in obstructive parameters, regardless of the alpha-blocker used, as urethral resistance factor and detrusor pressure maximum flow rate decreased by only 4 cm. H2O. There was a clear subjective and statistically significant decrease in International Prostate Symptom Score and quality of life scores of 6 and 2 points, respectively. No relevant statistical difference was noted among the effects of the 3 alpha-blockers on relieving symptoms or improving urodynamic parameters of obstruction. CONCLUSIONS: The alpha-blockers are effective for treating symptoms suggestive of bladder outlet obstruction in patients presenting with lower urinary tract symptoms but not for treating the obstruction.

Adrenergic alpha-Antagonists↗
PubMed2001

Impact of interferon therapy on the natural history of hepatitis C virus related cirrhosis.

BACKGROUND: The role of interferon treatment on the natural history of hepatitis C virus related cirrhosis is under debate. AIM: To evaluate the effect of interferon on the clinical course of compensated hepatitis C virus related cirrhosis. PATIENTS AND METHODS: Seventy two cirrhotic patients treated with interferon and 72 untreated controls matched treated patients with for quinquennia of age, sex, and Child-Pugh's score were enrolled in a prospective non-randomised controlled trial. Treated patients received leucocytic interferon alfa, with an escalating schedule for 12 months. The incidence and risk (Cox regression analysis) of clinical complications (hepatocellular carcinoma, ascites, jaundice, variceal bleeding, and encephalopathy) and death were calculated. RESULTS: Over median follow up periods of 55 months for treated and 58 for untreated subjects, seven and nine patients, respectively, died, and 20 and 32, respectively, developed at least one clinical complication (ns). Hepatocellular carcinoma developed in six treated and 19 untreated patients (p=0.018). Seven treated patients showed sustained aminotranferase normalisation and none died or developed complications. Clinical complications were significantly associated with low albumin, bilirubin, and prothrombin activity while hepatocellular carcinoma was significantly related to no treatment with interferon, oesophageal varices, and high alpha fetoprotein levels. By stratified analysis, the beneficial effect of interferon was statistically evident only in patients with baseline alpha fetoprotein levels > or =20 ng/ml. CONCLUSIONS: Interferon does not seem to affect overall or event free survival of patients with hepatitis C virus related cirrhosis while it seems to prevent the development of hepatocellular carcinoma. Patients who achieved sustained aminotransferase normalisation survived and did not develop any complications during follow up.

Antiviral Agents↗
PubMed2001

Beneficial effects of Batimastat (BB-94), a matrix metalloproteinase inhibitor, in rat experimental colitis.

BACKGROUND AND AIMS: Matrix metalloproteinases (MMPs) represent a group of enzymes that regulate cell-matrix composition playing a major role in the inflammatory response. In the present study we evaluated the ability of the MMP inhibitor Batimastat (BB-94) to modify the course of experimental colitis induced in the rat by trinitrobenzensulfonic acid (TNB). METHODS: Colitis was induced in 40 rats by intracolonic administration of TNB. Animals were divided into four groups of ten rats each: group 1 received only intracolonic TNB, group 2 received TNB+5 mg/kg intraperitoneal BB-94, group 3 TNB+10 mg/kg BB-94 and group 4 TNB+20 mg/kg BB-94. The MMP inhibitor was administered 30 min before induction of colitis and twice daily until death. Ten rats receiving only intracolonic 0.9% saline served as controls. Animals were killed after seven days; segments of colon were removed and used for histological score of inflammation and myeloperoxidase (MPO) activity. RESULTS: Rats receiving only intracolonic 0.9% saline showed no evidence of colitis. The inflammation score was 0.9, MPO activity 0.235 U/mg. Group 1 (TNB-treated rats) exhibited a high inflammation score (12.4) and MPO activity (0.715 U/mg). Conversely, BB-94-treated rats showed, compared to the TNB group, a significantly lower inflammation score and MPO activity in a dose-dependent fashion. Group 2: inflammatory score 10.1, MPO activity 0.474 (p < 0.05 vs. TNB); group 3: inflammatory score 8.3, MPO activity 0.287 (p < 0.01 vs. TNB); group 4: inflammatory score 5.0, MPO activity 0.256 (p < 0.01 vs. TNB). CONCLUSIONS: Treatment with BB-94 has dose-dependent beneficial effects on the inflammatory alterations in rat experimental colitis. Thus, the inhibition of MMPs may represent a novel therapeutic approach for treatment of intestinal inflammation.

Animals↗
PubMed2001

Endovascular repair as first-choice treatment for anastomotic and true iliac aneurysms.

PURPOSE: To report our experience with the endovascular repair of iliac aneurysms secondary to aortoiliac bypass grafting. METHODS: Thirteen patients (12 men; age range 62-86 years) with histories of aortoiliac reconstructions were treated with endovascular stent-grafts for 11 false and 2 true iliac aneurysms that averaged 5.2 cm in diameter (range 3.0-7.0). Via a percutaneous access and 9-F or 12-F sheaths, Passager or Wallgraft stent-grafts were delivered to exclude the aneurysms. RESULTS: Twelve (92%) of 13 interventions were completed satisfactorily; 1 procedure for a true iliac aneurysm was converted to traditional bypass grafting. Two patients underwent additional surgical procedures. The average hospital stay for the patients with endovascular repairs only was 3 days (range 2-5). After a mean follow-up of 28 months (range 17-40), no complication or endoleak has been detected in any patient, and all endografts are patent. CONCLUSIONS: Endovascular repair is an effective treatment for secondary aneurysms arising after aortoiliac surgery. It is less invasive and involves a shorter hospital stay. Endovascular repair should be the first choice treatment for iliac aneurysms.

Aged↗
PubMed2001

Direct costs of schizophrenia in Italian community psychiatric services.

OBJECTIVE: To estimate resource utilisation and direct costs of treatment for patients with schizophrenia in Italian Community Mental Health Centers (CMHCs). DESIGN: Multicentre, retrospective observational study. CMHCs recruited all patients who attended a follow-up consultation during the period September to December 1998. At enrollment, psychiatrists completed a questionnaire on consumption of resources in the 2 months before recruitment. SETTING: 14 CMHCs. PERSPECTIVE: Italian National Health Service (INHS). PATIENTS: 702 patients with a diagnosis of schizophrenia or other psychotic disorders, defined according to the Diagnostic and Statistical Manual of Mental Disorders-fourth edition. These patients had been followed by the CMHCs for at least 2 years and attended a follow-up consultation either during the period September to December 1998 or on randomly selected days during this period. Patients were classified into seven groups according to their diagnosis. RESULTS: The mean direct cost of patients with schizophrenia in the 2-month observation period was 2,234,475 Italian lire [L] (1154.01 Euro; EUR); direct costs ranged from L.1,545,818 to L.2,775,658 (EUR798.35 to EUR1433.51) by prognostic group. There was wide variability for prognostic groups in the impact of most cost components on total cost. Admissions accounted for between 11.4 and 56.3% of the total cost, daycare centre days for between 11.3 and 35.5%, home visits for 7.8 to 16.4%, and day-hospital days for 5.4 to 32.8%. Antipsychotics and anxiolytics were the most prescribed drugs and also the most costly. CONCLUSION: Despite the limitations of the study related to the short period considered, we believe this study offers some interesting information on the burden of schizophrenia, a disease for which its cost has received limited attention so far in Italy.

Adult↗
PubMed2001

Anthracyclines: selected new developments.

Anthracycline antibiotics play an important role in cancer chemotherapy. The need for an improvement of their therapeutic index has stimulated an ongoing search for anthracycline analogues with improved properties. Analogue development was originally limited by a lack of information on the cellular drug target, nevertheless almost 20 years ago the mechanism of action of doxorubicin and daunorubicin was revealed and DNA topoisomerase II was recognised to be their main cellular target. Several anthracyclines interfere with topoisomerase II functions by stabilizing a reaction intermediate in which DNA strands are cut and covalently linked to tyrosine residues of the enzyme. Investigations on the sequence specificity of doxorubicin in vitro and in nuclear chromatin of living cell have led to a molecular model of drug receptor on the topoisomerase II-DNA complex. Anthracyclines are likely placed at the interface between the DNA cleavage site and the active site of the enzyme, forming a DNA-drug-enzyme ternary complex. Moreover, a quite detailed structure-function relationship has been established for anthracyclines. First, drug intercalation is necessary but not sufficient for topoisomerase II poisoning; second, the removal of the 4-methoxy and 3'-amino substituents greatly increases the drug activity and third, the 3' substituent of the sugar moiety markedly influences the sequence selectivity of anthracycline-stimulated DNA cleavage. These relationships have been exploited during the last decade by several groups, including ours, in the search for new anthracycline drugs with lower side effects and higher activity against resistant cancer cells. This review will focus on areas of the anthracycline field including synthesis of new analogues, new strategies of synthesis and recent developments in the area of drug delivery.

Animals↗
PubMed2001

Long-term followup of randomized transurethral microwave thermotherapy versus transurethral prostatic resection study.

PURPOSE: We evaluate the durable effect of high-energy transurethral microwave thermotherapy and transurethral prostatic resection for treatment of patients with lower urinary tract symptoms suggestive of bladder outflow obstruction. MATERIALS AND METHODS: Between January 1996 and March 1997, 155 patients with lower urinary tract symptoms suggestive of bladder outflow obstruction were randomized to receive transurethral microwave thermotherapy (Prostatron*; device and commercial software) (82) or undergo transurethral prostatic resection (73). Initial patient evaluation was performed according to international standards. Patients were followed annually with the International Prostate Symptom Score (I-PSS) and uroflowmetry (maximum flow rate). The Kaplan-Meier survival analysis was used to calculate the cumulative risk of re-treatment, adjusted for loss to followup. RESULTS: A total of 78 patients received transurethral microwave thermotherapy and 66 underwent transurethral prostatic resection. Median followup was 33 months. In the thermotherapy group mean maximum urinary flow rate improved from 9.2 ml. per second at baseline to 15.1, 14.5 and 11.9 ml. per second at 1, 2 and 3 years, and mean I-PSS decreased from 20 to 8, 9, and 12, respectively. In the resection group the corresponding numbers for maximum urinary flow rate were 7.8, 24.5, 23.0 and 24.7 ml. per second at 1, 2 and 3 years, and for I-PSS were 20, 3, 4 and 3, respectively. At 36 months, 14 patients in the thermotherapy and 8 from the resection groups underwent re-treatment, and the cumulative risk was 19.8% (95% confidence interval 10.4% to 29.3%) and 12.9% (4.5% to 21.3%), respectively (p = 0.28). CONCLUSIONS: Transurethral microwave thermotherapy and transurethral prostatic resection achieve durable improvement in patients with lower urinary tract symptoms suggestive of bladder outflow obstruction, while the magnitude of improvement is higher with resection. The repeat thermotherapy is based on failure of therapy whereas repeat resection is based on complications of therapy.

Aged↗
PubMed2001

[Antibiotic therapy in Italy. Current data and proposals for the future].

Data concerning antibiotic therapy in italian ICUs are presented. These data were not directly measured: they have been derived from a previous study on costs of intensive care treatments. 78% of 1065 patients received antibiotic therapy. Empirical therapy was started in 82% of septic patients. 93% of septic patients had at least one antibiogram. In 96% of cases, 2 or more antibiotics were given. 85% of surgical non septic patients received antibiotic prophylaxis for an average of 3.6 days, with a 3rd generation cephalosporin in the majority of cases. 60% of medical non septic patients received antibiotic prophylaxis for an average of 6.2 days, mostly with a 3rd generation cephalosporin. These data raise doubts about the proper use of prophylaxis. These data can be considered a useful starting point for the development of a program of surveillance of infections in Italian ICUs.

Anti-Bacterial Agents↗
PubMed2001

[Bronchopulmonary infections].

Infections of the lower respiratory tract usually occurs during winter and are responsible for a high mortality and morbidity rate. The major clinical syndromes that are observed ranges from acute bronchitis to fatal pneumonia. In order to give optimal treatment and to avoid inappropriate use of antibiotics a careful diagnosis is necessary when signs and symptoms of lower respiratory tract infection are presents. Different clinical lower respiratory tract infections are presented with diagnostic and therapeutic approach considering actual belgium epidemiology.

Anti-Bacterial Agents↗
PubMed2001

[Third and fourth generation fluoroquinolones].

Levofloxacin, levorotatory isomer of ofloxacine, is the only FQ3G on the belgian market since the middle of 2000 and is a little more efficient than the FQ2G against S. pneumoniae. The FQ4G are in vitro active against the common and atypic respiratory pathogenes and significantly more efficient against the Gram positive cocci, principally against S. pneumoniae. Their long duration of action allows one oral administration a day sufficient to obtain bactericidal levels in the serum. Their secondary effects are located principally at the level of digestive tract, neurologic system or cutaneous area. In the U.S.A., several FQ4G (clina-, grepa-, spar-, trova-floxacin) were withdrawn from use after observance of severe toxicity, while there were being administrated on a large scale. Furthermore, two of these "respiratory" FQ4G (gemi- and moxi-floxacin) should reinforced our therapeutic armoury, moxifloxacin as of 2002 and gemifloxacin as of 2004. The position of FQ3G and 4G are in discussion. In the case of pneumonia acquired in the community and confirmed by X-Ray, our recommendation is to administer a new FQ at the first choice if the patient is allergic to penicillin, debilitated or if a penicillin resistant S. pneumoniae suspected (epidemiology, recent antibiotherapy) and at the second choice if it is resistance to penicillin or to macrolide, in case of atypic pneumonia. Today, the majority of the pneumonia acquired outside the hospital is empirically treated with a betalactam (oral or intravenous), with or without macrolide. The new FQ are important drugs. One must avoid overprescription which leads to bacterial resistance (especially S. pneumoniae).

Administration, Oral↗