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F Vianello

Publications and source records attributed to F Vianello.

At least 19 recordsLinked to original sources
PubMed2003

Biphasic behavior of the kinetics of 31P-containing metabolites in ischemic porcine kidneys.

The assessment of kidney viability before transplantation (with a view of discarding nonviable organs) remains an obstacle to confidently extending organ harvesting to marginal donors. In the present study phosphorus magnetic resonance spectroscopy was used to monitor metabolic changes in (31)P-containing metabolites in isolated porcine kidneys. After various warm ischemia times, the organs were stored at 0 degrees C. Time-dependent changes in the phosphomonoester/inorganic-phosphate ratio were recorded at 0 degrees C were shown to follow a biexponential decay. The first-order kinetic rate constant of the short-time decay was strongly dependent on the warm ischemia time, a result that was discreted in terms of the underlying biochemistry. The metabolic events responsible for the dramatic decrease in phosphomonoester/inorganic phosphate ratio that occur immediately after organ perfusion and storage, suggest that any procedure to minimize organ damage must occur immediately after harvesting.

Animals↗
PubMed2003

GnRH agonist treatment before total laparoscopic hysterectomy for large uteri.

STUDY OBJECTIVE: To evaluate whether uterine shrinkage induced by gonadotropin-releasing hormone (GnRH) agonists in women with a large uterus (>14 wks) may facilitate total laparoscopic hysterectomy. DESIGN: Randomized, prospective study (Canadian Task Force classification I). SETTING: University-affiliated hospital. PATIENTS: Sixty-two women with symptomatic uterine myomas (size 16-20 wks). INTERVENTIONS: Total laparoscopic hysterectomy for benign pathology. MEASUREMENTS AND MAIN RESULTS: Before surgery, women were assigned, at a ratio of 1:1 by random selection, to receive injections of triptorelin depot 11.25 mg 3 months before surgery (group A) or no treatment (group B). Uterine volume, mean operating time, uterine weight, drop in hemoglobin, intraoperative complications, conversions to laparotomy, and hospital stay were recorded. Triptorelin decreased uterine volume, calculated by ultrasonography, by 26.5% in group A, whereas the volume remained unchanged in group B. Statistical differences were found between groups concerning uterine weight, operating time, and drop in hemoglobin level. Three patients in group B were converted to laparotomy because of uterine size. CONCLUSION: In women with a large uterus, a 3-month preoperative course of GnRH may facilitate laparoscopic hysterectomy, decreasing uterine size, operating time, and blood loss.

Antineoplastic Agents, Hormonal↗
PubMed2002

Hepatosplenic gammadelta T-cell lymphoma presenting with immune-mediated thrombocytopenia and hemolytic anemia (Evans' syndrome).

We describe an unusual case of hepatosplenic T-cell lymphoma in a 61-year-old man who presented with fever, hepatosplenomegaly, anemia, and thrombocytopenia. A spleen biopsy was consistent with T-cell lymphoma. Cytogenetic studies did not reveal chromosome abnormalities. Using the polymerase chain reaction approach, clonality of the T-cell receptor gamma-chain gene rearrangement could be demonstrated, while Southern blot analysis disclosed only a germline configuration of the T-cell receptor beta chain genes. Of interest, an immune-mediated mechanism was demonstrated and was most likely responsible for erythrocyte and platelet destruction; this is, therefore, the first report of gamma T-cell lymphoma in association with Evans' syndrome. Initial steroid treatment was efficacious in limiting autoimmunity but constitutional symptoms did not subside. Chemotherapy (MACOP-B) was successful in obtaining complete clinical remission. Finally, thrombocytopenia in gammadelta T-cell lymphoma patients should be routinely evaluated for platelet autoantibodies.

Anemia, Hemolytic↗
PubMed2002

A study of hysteroscopic metroplasty in 141 women with a septate uterus.

141 patients who had a hysteroscopic septum resection of a partial uterine septum (class Vb, American Society for Reproductive Medicine, ASRM) were divided into two groups: Group I (69 patients) presented with infertility and Group II (72 patients) with recurrent abortion. The mean+/-SD post-operative follow up period was 36+/-19.5 months. Thiry-six Group I patients (52.1%) and 38 Group II patients (52.7%) achieved pregnancy, with respective abortion rates of 20% and 25%.

Abortion, Habitual↗
PubMed2002

Tentative guidelines and practical suggestions to avoid venous thromboembolism during oral contraceptive therapy.

Oral contraceptive therapy (OCT) is widely used in the world. It is usually safe and effective but side effects are occasionally seen. Venous thromboembolism is one of the most feared side effects. To avoid this complication adequate guidelines are needed. These have to take into account family history, personal history, and suitable laboratory investigations. The presence of an idiopathic venous thrombosis in the family or in the personal history is of paramount importance. However it is often difficult to ascertain whether a venous thrombosis is idiopathic or not. Even when there is doubt, a coagulation study should be carried out. An adequate coagulation study in this case should include at least an evaluation of antithrombin, protein C, and protein S. A search for homozygosity of factor V Leiden appears advisable. These defects represent absolute contraindications to the use of OCT. Relative contraindications may be represented by other minor coagulation disorders such as heterozygous factor V Leiden, fibrinolysis defects, and a G-to-A 20210 prothrombin abnormality. Other noncoagulation-related conditions such as hypertension, liver damage, and obesity may represent absolute or relative contraindications to the use of OCT.

Contraceptives, Oral↗
PubMed2001

A new factor X defect (factor X Padua 3): a compound heterozygous between true deficiency (Gly(380)-->Arg) and an abnormality (Ser(334)-->Pro).

We report a novel mutation in Factor X (FX) gene which results in a phenotype without any bleeding tendency. The proband has been found to be a compound heterozygote between a novel FX true deficiency (Gly(380)-->Arg) and a previously reported dysfunctional mutation Ser(334)-->Pro (FX Marsiglia). Prothrombin time (PT) and partial thromboplastin time (PTT) were moderately prolonged and were fully corrected by the addition of normal serum. Her FX activity level varied between 8% and 19% of normal according to the method used whereas the FX antigen level was 40% of the normal control value. All the exons and intron/exon junctions of the FX gene were studied using a combined approach of polymerase chain reaction and conformation sensitive gel electrophoresis. A transversion G to A in exon 8 resulting in the replacement of Gly380 by Arg was found in the proband, in the father and in a proband's brother, whereas heterozygous FX Marsiglia was present in the proband's mother and her sister. Gly380 is strictly linked to Ser379, a component of the catalytic triad. The substitution of Gly for Arg causes the introduction of a large charged amino acid which could affect the catalytic function of FX leading to secretion problem, accounting for the cross-reactive material (CRM) negative phenotype.

Adult↗
PubMed2001

Deuterium nuclear magnetic resonance for evaluating the metabolic status of livers subjected to warm ischemia.

BACKGROUND: The development of reliable methods for assessing the viability of currently available livers is expected to increase the number of successful transplantations. METHODS: 2 H nuclear magnetic resonance (NMR) was used to search for metabolic markers of ischemia in explanted rat livers. Deuterium oxide (2 H2O) was used as a source of 2 H. A total of 10-80% v/v 2 H2O was added to homogenates obtained from a liver biopsy and the formation of 2 H-labeled metabolites was monitored. RESULTS: Some well-resolved 2 H resonances were found in the homogenates from biopsies of warm ischemic liver. Two of these were identified as [3-2 H] lactate and [2-2 H] lactate, and a linear relationship was found between the ratio of [[2-2 H] lactate] to [[3-2 H] lactate] and the warm ischemia time. The deuterium incorporation into lactate was explained on the basis of the metabolic events occurring under hypoxic conditions. CONCLUSIONS: The experimental results support the application of 2 H NMR for a reliable evaluation of the metabolic status of a liver harvested from non-heart-beating donors.

Animals↗
PubMed2001

A dysfunctional factor X (factor X San Giovanni Rotondo) present at homozygous and double heterozygous level: identification of a novel microdeletion (delC556) and missense mutation (Lys(408)-->Asn) in the factor X gene. A study of an Italian family.

Low levels of factor X (F.X) were detected in a 4-year-old boy who experienced acute lymphoblastic leukemia and bleeding manifestations. Laboratory data suggested the presence of a dysfunctional F.X molecule. Two novel F.X gene mutations were identified in the proband that was double heterozygous for both: a microdeletion (delC556) in exon VI resulting in a frameshift leading to a termination codon at position 226. This deletion was found in six family members with reduced F.X antigen and activity levels. A second mutation characterised by a G(1344)-->C transversion in exon VIII was detected in the proband resulting in a Lys(408)-->Asn substitution. This latter mutation was present in several asymptomatic family members from the paternal and the maternal side. The proband's sister was homozygous for the Lys(408)-->Asn substitution and exhibited low F.X activity with a normal antigen level. The naturally occurring F.X Lys(408)-->Asn (F.X(K408N)) variant was isolated from plasma of either homozygous or double heterozygous individuals. NH(2)-terminal sequencing of the heavy chain of F.X(K408N) failed to show any sequence abnormality in patients who were also carriers of the delC556, suggesting that this latter lesion accounted for the lack of F.X synthesis. Purified F.X Lys(408)-->Asn had an identical behaviour to normal F.X as judged by SDS-PAGE and immunoblotting. Clotting assay using purified F.X(K408N) and F.X-deficient plasma resulted in a laboratory phenotype similar to that observed in a homozygous subject for F.X Lys(408)-->Asn substitution. This is the first characterisation of a naturally occurring F.X variant with a mutation at the COOH-terminal end of the molecule.

Amino Acid Sequence↗
PubMed2001

Prevalence of intestinal metaplasia in the distal oesophagus, oesophagogastric junction and gastric cardia in symptomatic patients in north-east Italy: a prospective, descriptive survey. The Italian Ulcer Study Group "GISU".

BACKGROUND: Incidence of adenocarcinoma of distal oesophagus and gastric cardia, probably arising from areas of intestinal metaplasia, has been increasing rapidly. AIMS: To define prevalence of intestinal metaplasia of distal oesophagus, oesophagogastric junction and gastric cardia and to evaluate potential associated factors, by means of a prospective multicentre study including University and teaching hospitals, and primary and tertiary care centres. PATIENTS: Each of 24 institutions involved in study enrolled 10 consecutive patients undergoing first-time routine endoscopy for dyspeptic symptoms. METHODS: Patients answered symptom questionnaires and underwent gastroscopy Three biopsies were taken from distal oesophagus, oesophago-gastric junction and gastric cardia, and were stained with haematoxylin and eosin. Specimens were also evaluated for Helicobacter pylori infection. RESULTS: A total of 240 patients (124 male, 116 female; median age 56 years, range 20-90) were enrolled in study. Intestinal metaplasia affected distal oesophagus in 5, oesophago-gastric junction in 19 and gastric cardia in 10 patients. Low-grade dysplasia was found at distal oesophagus and/or oesophago-gastric junction of 3/24 patients with intestinal metaplasia vs 2/216 without intestinal metaplasia (p<0.05). A significant association was found between symptoms and presence of intestinal metaplasia, regardless of location, and between Helicobacter pylori infection and intestinal metaplasia at oesophago-gastric junction. CONCLUSIONS: Intestinal metaplasia of distal oesophagus, oesophagogastric-junction and gastric cardia is found in a significant proportion of symptomatic patients undergoing gastroscopy and is associated with dysplasia in many cases. Although prevalence of dysplasia seems to decrease when specialized columnar epithelium is found in short segment, or even focally in oesophago-gastric junction, these small foci of intestinal metaplastic cells may represent source of most adenocarcinomas of cardia.

Barrett Esophagus↗
PubMed2001

Early transfusion of factor VIII/von Willebrand factor concentrates seems to be effective in the treatment of gastrointestinal bleeding in patients with von Willebrand type III disease.

The association between gastrointestinal angiodysplasia and von Willebrand disease was reported 30 years ago. The clinical course of patients with von Willebrand disease and angiodysplasia is characterized by numerous admissions to hospital for gastrointestinal bleeding necessitating transfusion with packed red cells, factor VIII and plasma. The management of these patients is problematic. Numerous treatments for the gastrointestinal bleeding have been proposed: surgery, electrocoagulation, laser photocoagulation, sclerotherapy, arteriography with embolization, immunoglobulins, oestrogens, and octreotide, but no treatment modality has been successful in all cases. We report a 66-year-old-female with small bowel angiodysplasia and von Willebrand type III disease in whom prompt administration of factor VIII/vWF concentrates was effective. Education of patients to recognize minimal gastrointestinal bleeding manifestations, periodical clinical visits and early infusion of factor VIII/vWF seems to be fundamental for the success of this therapy. A longer follow-up and the study of other patients are needed to confirm our observation.

Aged↗
PubMed2001

Mild bleeding diathesis in a boy with combined severe haemophilia B (C(10400)-->T) and heterozygous factor V Leiden.

Haemophilia B patients with factor IX (FIX) activity < 1% are usually characterized by severe bleeding episodes early in life. We report a case of sporadic severe haemophilia B, clinically characterized by mild bleeding diathesis. The presence of anamnestic thrombophlebitis in the patient's mother prompted us to investigate a possible associated hypercoagulable condition. Resistance to activated protein C due to factor V R506Q mutation was present in the mother and in the propositus, in the homozygous and heterozygous form, respectively. Molecular analysis of the FIX gene led to the identification of a nonsense mutation resulting in a stop codon at position 50, previously described and usually responsible for a severe pattern of haemophilia B. The implications of this unusual association are discussed.

Activated Protein C Resistance↗
PubMed2001

Stable free radicals as ubiquitous components of red wines.

A stable ESR signal, centred at g = 2.0037 +/- 0.0002, characterised by a single resonance and assignable to a free radical, was found in all the bottled red wines, both commercial and experimental, that we have examined. The radical concentration was calculated to be in the range of 5-82 nM. After exposure of the wines to air for a few minutes a two fold increase of the ESR signal, followed by a slow decrease with time, was observed. The intensity of ESR signal in experimental red wines, was found to increase with the ageing of the wines and was strictly correlated to the total content of polyphenols. The formation of semiquinone radicals of polyphenols is suggested as one possible mechanism leading to the presence of stable free radicals in red wines.

Electron Spin Resonance Spectroscopy↗
PubMed2001

Low-dose flutamide (125 mg/day) as maintenance therapy in the treatment of hirsutism.

OBJECTIVE: To evaluate the safety and efficacy of a low dose of flutamide (125 mg/day) in maintaining the clinical results already obtained using a higher dose (250 mg/day), in women suffering from hirsutism. METHOD: Forty-three women suffering from hirsutism of varying origin received 250 mg/day of flutamide as an initial treatment for 12 months and, subsequently, 125 mg/day of flutamide for an additional 12 months as a maintenance treatment. Hirsutism was evaluated by the Ferriman-Gallwey score, and hair diameter and hair growth rate were determined by a special image analysis processor. Biochemical, clinical and hormonal parameters were evaluated in basal conditions and every 2-6 months. RESULTS: The significant decrease in the hirsutism score, hair diameter and hair growth rate during the initial treatment period was confirmed at the end of the maintenance treatment period. Androgen levels decreased up to the end of the initial treatment period and partially decreased during the maintenance treatment. During the initial treatment period, 4 subjects showed an increase of aspartate aminotransferase and alanine aminotransferase and dropped out. During the maintenance treatment period, no side effects or complications were observed. CONCLUSION: Satisfactory management of hirsutism with flutamide seems to be represented by an initial treatment period using 250 mg/day to achieve satisfactory results, followed by a long maintenance treatment period using 125 mg/day.

Adult↗
PubMed2001

Colonic metaplasia in the long-term follow-up of the ileal neobladder.

OBJECTIVE: To look for the presence of colonic metaplasia (CM), the shifting from sialomucins (SIs) to sulfomucins (SUs), considered as a probably premalignant lesion in the stomach in the mucosa of the ileal neobladder (IN). METHODS: 19 patients with IN were subjected to endoscopic biopsy; the samples were analyzed by means of histochemistry with high iron diamine, a test indicated to identify SIs and SUs. RESULTS: CM was never observed earlier than 1 year after the operation, was absent in 9/19 patients (mean follow-up 14 months) and present in 10/19 (mean follow-up 59 months). CONCLUSION: Time-dependent phenotypic changes, already described in the stomach as being premalignant, take place after constant contact with urine in the mucosa of the IN. It is at present unclear whether they may be defíned as only metaplastic or frankly preneoplastic; anyway, a careful follow-up remains indicated in all patients with íntestinal urinary diversions.

Aged↗
PubMed2000

Preparation, morphological characterization, and activity of thin films of horseradish peroxidase.

Active uniform films of horseradish peroxidase (HRP) have been prepared by covalent binding on Si/SiO(2) or glass supports previously activated by silanization and succinylation. Labeling by fluorescent or by Electron Spin Resonance (ESR) probes was used to quantify the surface density of active groups and of horseradish peroxidase. Atomic Force Microscopy (AFM) imaging was used to characterize the surface morphology. We observed that a non-uniform protein adsorption due to physical interactions was present when the supports were not activated for covalent binding and was, in large part, removed by washing. The enzyme deposited by covalent binding formed homogeneous layers with a height in the range 60-90 A. By using a fluorescent label, we calculated a protein density of 3.6 x 10(12) molecules cm(-2) on Si/SiO(2), corresponding to an estimated area per molecule of 2800 A(2) which is in agreement with the value expected on the basis of the crystallographic data considering the formation of a monomolecular layer. The protein density of the layer immobilized on glass was similar (1.9 x10(12) molecules cm(-2)). The enzyme immobilized on both supports showed a k(cat)/K(M) being of the order of 3-5x10(5) M(-1)s(-1) that is 1/20th of free HRP. The half-life time of the activity of the enzyme immobilized by covalent binding was longer than 40 days at 6 degrees C.

Bisphenol A-Glycidyl Methacrylate↗
PubMed2000

Contribution of proanthocyanidins to the peroxy radical scavenging capacity of some Italian red wines.

Highly reactive radicals, ROO(*), were generated from 2, 2'-azobis[2-(2-imidazolin-2-yl)propane] and linoleic acid. The ROO(*) scavenging capacity of some Italian red wines was evaluated following the changes in oxygen consumption. Under the experimental conditions the time course of oxygen consumption shows two typical behaviors: trolox-like (class I) and gallic acid-like (class II). Usually the time course of wine was similar to that of gallic acid. The rate of oxygen consumption was found to decrease exponentially with the amount of wine or gallic acid added to the test solution. On this basis the capacity of red wines to scavenge peroxy radicals was expressed as content of gallic acid (S(GA)). The S(GA) values were found to be correlated to the amount of total proanthocyanidins and total polyphenols of some Italian red wines (p < 0.01). The proanthocyanidins extracted from seeds were shown to make a major contribution to the peroxy radical scavenging capacity of red wines, whereas, interestingly, the chemical class of the low molecular weight tannins reactive to vanillin did not correlate with the S(GA) values.

Anthocyanins↗