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Biomedical subjects

G Ferretti

Publications and source records attributed to G Ferretti.

At least 55 records · Page 3Linked to original sources
PubMed2004

Morphological, histochemical and phytochemical investigation of the genus Hypericum of the Central Italy.

Eight entities of the genus Hypericum that spontaneously grow on the Central Italy (Appennino Umbro-Marchigiano) have been studied under the morphological, histochemical and phytochemical aspects. From the morphological standpoint, they differ in the shape and size of flowers and leaves and in the dimension and distribution of the secretory structures through the various parts of the plant. It has been possible, with the histochemical and phytochemical studies, to localize and identify some secondary metabolites inside the secretory structures.

Humans↗
PubMed2004

Low-dose intramuscular hepatitis B immune globulin and lamivudine for long-term prophylaxis of hepatitis B recurrence after liver transplantation.

The combination of lamivudine and hepatitis B immunoglobulins (HBIg) to prevent recurrence of HBV hepatitis has significantly improved the survival of patients transplanted for HBV-related end-stage liver disease. Generally, HBIg are administered intravenously. We evaluated the efficacy, tolerability, and cost savings of long-term intramuscular HBIg and lamivudine in 28 patients (23 men and 5 women), who received liver transplants for acute or chronic HBV-related liver disease. Twelve patients started lamivudine before and 16 at the time of liver transplantation. HBIg were administered intravenously during the first week (50 to 70,000 IU) and intramuscularly thereafter (1200 IU every 3 to 6 weeks) to maintain an HbsAb titer >100 IU/L. Mean follow-up was 20 +/- 13 months. Only one patient experienced HBV recurrence (9 months after transplantation). This patient had failed to follow the scheduled prophylaxis. Cumulative survival at 3 years was 83%. Intramuscular HBIg were well tolerated in all cases. Cost analysis comparing intramuscular vs intravenous HBIg administration showed that 39,490 Euros were saved per patient per year. These preliminary results show that low-dose intramuscular HBIg and lamivudine are efficacious and cost-effective for long-term prophylaxis of hepatitis B recurrence after liver transplantation.

Antiviral Agents↗
PubMed2004

[Surgical and/or endoscopic treatment of acquired tracheal stenosis in adult patients].

OBJECTIVES: Retrospective survey (over 13 Years) of the surgical treatment of 46 acquired tracheal stenosis, in adult patients. Our goals were to study their epidemiology, changes in the surgical technique with the cervical or endoscopic approach, and the recent contribution of endoprotheses. MATERIALS AND METHODS: Sixty-six therapeutic procedures were performed for 46 tracheal stenoses. Most of stenoses were post-intubation and/or post-tracheotomy and were fixed in 50% of the cases. We used 21 sleeve resections with end-to-end anastomoses, 9 tracheal stents, 27 dilations, 6 calibrations, and 3 electro-coagulations. RESULTS: The sleeve resection gave 91% success (1 failure and 1 death). The endoscopic treatments were less efficient: 79% for tracheal stents (2 mobilizations), 50% success for iterative dilations. The respiratory tests were meaningfully improved with a mean follow-up of 18 Months. CONCLUSION: Sleeve resection remains the gold standard treatment. For all temporary or definitive contraindications to open surgery, tracheal stents would be an excellent alternative to avoid often inefficient iterative dilations.

Adolescent↗
PubMed2004

[Bronchial carcinoid tumors: role of imaging for diagnosis and local staging].

PURPOSE: To describe the imaging features of bronchial carcinoids and to define the role of CT as a diagnostic and pretherapeutic tool. MATERIALS AND METHODS: We performed a retrospective study including 54 carcinoids. We evaluated and compared the clinical, radiographic, CT, fiberoptic, and pathologic data. RESULTS: At presentation, the mean age was 48.5 years (14-81) and patients mainly complained of signs related to bronchial obstruction (55.7%). 72% of bronchial carcinoids were located in the proximal airway. CT showed calcifications in 26% of 54 cases and contrast enhancement in 60%. Typical carcinoids differed from atypical carcinoids in their size and lymph node extension. As compared to fiberoptic bronchoscopy, CT identified proximal carcinoids with exo-bronchial extension (7.4%), peripheral tumors (20.4%), and parenchymal complications. The sensitivity and predictive positive-value of CT for lymph node extension was 28% and 20%, respectively. CONCLUSION: CT is a useful technique for diagnosing and localizing bronchial carcinoids. The results of CT in determining lymph node extension is disappointing, and should raise caution in case of localized treatment using fiberoptic bronchoscopy.

Adolescent↗
PubMed2004

Effect of non-enzymatic glycation on aluminium-induced lipid peroxidation of human high density lipoproteins (HDL).

BACKGROUND AND AIM: Several studies have shown that non-enzymatic glycation and oxidative damage play an important role in the pathogenesis of neurological diseases. Increased levels of advanced glycation end-products (AGEs) and of lipid peroxidation products have been observed in the brain, in the cerebrospinal fluid (CSF) and in the plasma of subjects affected by Alzheimer's disease (AD). The aim of this study was to investigate the effect of non-enzymatic glycation on aluminium-induced lipid peroxidation and on the stimulatory effect exerted by aluminium on iron-triggered oxidation of high density lipoproteins (HDL) isolated from human plasma. METHODS AND RESULTS: Aluminium (10-200 microM) and iron (20 microM) induced a significant increase in lipid hydroperoxides in HDL compared to untreated HDL. Therefore, our results confirm that aluminum and iron exert an oxidant effect on HDL. Moreover, aluminium exerted a stimulatory effect on iron-induced lipid peroxidation of HDL, in agreement with our previous studies. The aluminum/iron-induced increase in lipid hydroperoxides was significantly higher in HDL incubated for different time periods (24-72 hours) in the presence of 50 mM glucose (Gly-HDL) compared to HDL incubated alone. These results demonstrate that Gly-HDL is more susceptible to aluminium and iron-oxidative treatment with respect to control HDL. CONCLUSION: We suggest that aluminium and iron-induced oxidative damage on HDL could be involved in the development of neurological diseases and that glycation of HDL could represent an additional risk factor for these human diseases.

Adult↗
PubMed2004

Factor V Leiden and G20210A prothrombin mutation and the risk of subclavian vein thrombosis in patients with breast cancer and a central venous catheter.

BACKGROUND: To analyze the influence of the prothrombotic gene mutation factor V G1691A (factor V Leiden) and prothrombin G20210A on the risk of a first episode of catheter-related deep venous thrombosis (DVT) in a group of patients with breast cancer treated with chemotherapy. PATIENTS AND METHODS: Between January 1999 and February 2001, the occurrence of a first symptomatic DVT was investigated in a cohort of 300 consecutive patients with locally advanced or metastatic breast cancer treated at a single institution with fluorouracil-based chemotherapy, administered continuously through a totally implanted access port. A nested case-control study included 25 women (cases) with catheter-related DVT and 50 controls without DVT matched with cases for age, identical chemotherapy, stage of disease and prognostic features. The G1691A factor V and G20210A prothrombin mutation genotypes were analyzed. RESULTS: Five cases [20%; 95% confidence interval (CI) 9% to 39%)] and two controls (4%; 95% CI 1% to 14%) were heterozygous carriers of G1691A factor V (P = 0.04). The age-adjusted odds ratio for catheter-related DVT was 6.1 (95% CI 1.1-34.3). Only one patient (case) had the G20210A prothrombin gene mutation. Time from start of chemotherapy infusion to DVT was not significantly different between patients with (median 31 days) and without (median 43 days) G1691A factor V mutation (P = 0.6). CONCLUSIONS: Factor V Leiden carriers with locally advanced or metastatic breast cancer have an increased risk of developing catheter-related DVT during chemotherapy.

Adult↗
PubMed2004

Incidence of chemotherapy-induced amenorrhea depending on the timing of treatment by menstrual cycle phase in women with early breast cancer.

BACKGROUND: The aim of this study was to characterize the factors associated with chemotherapy-induced amenorrhea (CIA) and to examine whether the phase of the menstrual cycle at chemotherapy start could affect the rate of CIA in premenopausal women with early breast cancer. METHODS: CIA was defined as the cessation of menses for at least 3 months during or after chemotherapy. Menstrual phase was defined as days 1-6, follicular phase as days 7-14, luteal phase as days 15-20 and premenstrual phase as days 21-28. Univariate and multivariate predictors of CIA were examined. RESULTS: Among 111 premenopausal women, univariate analysis showed a higher incidence of CIA in patients treated in the follicular phase rather than in other menstrual cycle phases (67.6% compared with 45.5%; P=0.03). The rate of CIA increased with age: 65.2% and 45.8% in patients aged >42 and </=42 years, respectively (P=0.05). Upon multivariate analysis these differences remained statistically significant and duration of chemotherapy of more than six cycles correlated significantly with the incidence of CIA (P=0.03). CONCLUSIONS: The major implication of this analysis is that the timing of treatment within the menstrual cycle may potentially modulate the onset of CIA. This work and its future confirmation using prospective randomized trials would be useful in predicting the likelihood of CIA and in counseling breast cancer patients, especially those with a good prognosis who benefit less from chemical castration.

Adult↗
PubMed2004

Protective effect of paraoxonase activity in high-density lipoproteins against erythrocyte membranes peroxidation: a comparison between healthy subjects and type 1 diabetic patients.

High-density lipoproteins (HDL) plays a key role in the protection against oxidative damage of lipoprotein and biological membranes. The aim of the present study was to investigate the relationship between the antioxidant role of HDL and the HDL-paraoxonase (PON) activity in healthy subjects and in type 1 diabetic patients. Moreover, the ability of HDL of controls and diabetic patients to protect and/or repair biological membranes from oxidative damage was studied. HDL were isolated from 31 type 1 diabetic patients and 31 sex- and age-matched healthy subjects and immediately used to evaluate lipid hydroperoxides and HDL-PON activity. Erythrocyte membranes obtained from healthy subjects were oxidized with 2,2-azo-bis(2-aminidinopropane)dihydrochloride and then incubated in the presence of HDL isolated from healthy or type 1 diabetic subjects, with measurements of membrane lipid hydroperoxides before and after the incubation. HDL from type 1 diabetic patients showed higher levels of lipid hydroperoxides and a lower activity of HDL-PON than healthy subjects. Moreover, HDL of type 1 diabetic patients protected less efficiently erythrocyte membranes against oxidative damage compared with HDL from healthy subjects. A negative correlation was found between HDL-PON activity and the levels of hydroperoxides of HDL, confirming the relationship between PON and lipid peroxidation and suggesting that subjects with low PON activity are more exposed to oxidative damage than subjects with high PON activity. The ability of HDL to protect erythrocyte membranes was positively correlated with HDL-PON activity and negatively correlated with the levels of lipid hydroperoxides of HDL of healthy subjects. These results confirm a linkage between PON activity and lipid peroxidation of lipoproteins and suggest that the ability of HDL to protect erythrocyte membranes might be related to the PON activity. It might be hypothesized that the decrease of PON activity in diabetic patients and the lower HDL protective action against membrane peroxidation could contribute to acceleration of arteriosclerosis in type 1 diabetes mellitus.

Adult↗
PubMed2004

Modification induced by homocysteine and low-density lipoprotein on human aortic endothelial cells: an in vitro study.

The aim of the present study was to investigate the effect exerted by low-density lipoprotein (LDL) modified by homocysteine (Hcy)-thiolactone (Hcy-LDL) on functional properties on human endothelial cells. Hcy-thiolactone, a reactive product formed in human cells from enzymatic conversion of Hcy, was hypothesized to play an important role in Hcy-induced vascular damages. Using endothelial cultured cells [human aortic endothelial cells (HAEC)] as cellular model, we evaluated nitric oxide (NO) production, cytoplasmic Ca(2+) levels, Na(+)/K(+)-ATPase activity, and peroxynitrite production in cells incubated in the presence of control LDL or Hcy-LDL. Homocysteinylation of LDL was carried out by incubation of LDL, isolated from plasma of healthy subjects, with 100 microm Hcy-thiolactone. A significant increase in cytoplasmic Ca(2+) levels and peroxynitrite production and a decrease in Na(+)/K(+)-ATPase and NO production in HAEC incubated with Hcy-LDL compared with HAEC incubated with control LDL were observed. Moreover, a positive correlation was found between Na(+)/K(+)-ATPase activity and cytoplasmic Ca(2+) content and between peroxynitrite activity and cytoplasmic Ca(2+) content. In conclusion, our results demonstrated that LDL homocysteinylated in vitro induced alterations of functional properties and NO metabolism of human endothelial cells.

Adult↗
PubMed2004

[Preclinical and clinical results with the epidermal growth factor receptor inhibitor Gefitinib (ZD1839, Iressa)].

Since epidermal growth factor receptor (EGFR) is involved in tumor proliferation and angiogenesis, and in the mechanisms of resistance to chemo- and hormono-therapy, it represents a unique promising target for anticancer treatment. Gefinitib (Iressa, ZD1839), an inhibitor of the EGFR tyrosine kinase activity able to bind the intracellular domain of the receptor, is at present in clinical development. In preclinical models Gefitinib induced a dose-dependent response rate in tumor xenografts obtained from different human cancer cells lines. The expression of EGFR in the prior tumor did not appear to be a predictive marker for Gefitinib sensitivity. Furthermore, long-term drug use was well tolerated in mice without inducing resistance. However, tumors started to grow again after treatment interruption. Laboratory findings and in vivo data have prompted the evaluation of Gefitinib administered as a single oral daily dose alone or in combination with conventional anticancer treatment.

Animals↗
PubMed2003

Binding of nicotine and homoazanicotine analogues at neuronal nicotinic acetylcholinergic (nACh) receptors.

A total of 20 substituted analogues of nicotine (1a) and homoazanicotine (3a) were examined in order to determine whether or not they might bind in a similar manner at alpha4beta2 nicotinic acetylcholinergic (nACh) receptors. It was found that parallel structural changes in the two series resulted in parallel shifts in affinity. Evidence suggests that the two series are binding in a comparable fashion.

Humans↗
PubMed2003

Severity assessment of acute pulmonary embolism: evaluation using helical CT.

The objective was to evaluate the helical CT (HCT) criteria that could indicate severe pulmonary embolism (PE). In a retrospective study, 81 patients (mean age 62 years) with clinical suspicion of PE explored by HCT were studied. The patients were separated into three different groups according to clinical severity and treatment decisions: group SPE included patients with severe PE based on clinical data who were treated by fibrinolysis or embolectomy ( n=20); group NSPE included patients with non-severe PE who received heparin ( n=30); and group WPE included patients without PE ( n=31). For each patient we calculated a vascular obstruction index based on the site of obstruction and the degree of occlusion in the pulmonary artery. We noted the HCT signs, i.e., cardiac and pulmonary artery dimensions, that could indicate acute cor pulmonale. According to multivariate analysis, factors significantly correlated with the severity of PE were: the vascular obstruction index (group SPE: 54%; group NSPE: 24%; p<0.001); the maximum minor axis of the left ventricle (group SPE: 30.2 mm; group NSPE: 40.4 mm; p<0.001); the diameter of the central pulmonary artery (group SPE: 32.4 mm; group NSPE: 28.3 mm; p<0.001); the maximum minor axis of the right ventricle (group SPE: 47.5 mm; group NSPE: 42.7 mm; p=0.029); the right ventricle/left ventricle minor axis ratio (group SPE: 1.63; group NSPE: 1.09; p<0.0001). Our data suggest that hemodynamic severity of PE can be assessed on HCT scans by measuring four main criteria: the vascular obstruction index; the minimum diameter of the left ventricle; the RV:LV ratio; and the diameter of the central pulmonary artery.

Case-Control Studies↗
PubMed2003

Coenzyme Q10, antioxidant status and ApoE isoforms.

The aim of this study was to inquire the antioxidant status in plasma and lipoproteins isolated from normal subjects possessing different ApoE genotypes. For this purpose we investigated blood samples from 106 healthy blood donors: the distribution of ApoE alleles (E2/E2 = 0.9%, E2/E3 = 10.4%, E2/E4 = 2.8%, E3/E3 = 71.7%, E3/E4 = 12.3% and E4/E4 1.9% with 1, 11, 3, 76, 13, and 2 subjects respectively for each genotype) was in agreement with previous data. Almost no differences were found in the concentrations of both coenzyme Q10 (CoQ10) and vitamin E for the different genotypes. Concentration of CoQ10 in isolated lipoproteins was also similar, in the different genotypes, when referred to cholesterol; CoQ10 in LDL was higher for the E3/E3 subjects when referred to protein. Neither CoQ10 nor vitamin E correlated with paraoxonase (PON) activity or cholesteryl-ester hydroperoxides (CHP). Furthermore, there was no correlation between the same lipophilic antioxidants and CHP levels. The only E2 homozygous subject found had high levels of PON and low levels of CHP; the two E4/E4 subjects had low PON activity together with low levels of CHP.

Alleles↗