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R Calabrese

Publications and source records attributed to R Calabrese.

At least 19 recordsLinked to original sources
PubMed2006

Predicting the insurgence of human genetic diseases associated to single point protein mutations with support vector machines and evolutionary information.

MOTIVATION: Human single nucleotide polymorphisms (SNPs) are the most frequent type of genetic variation in human population. One of the most important goals of SNP projects is to understand which human genotype variations are related to Mendelian and complex diseases. Great interest is focused on non-synonymous coding SNPs (nsSNPs) that are responsible of protein single point mutation. nsSNPs can be neutral or disease associated. It is known that the mutation of only one residue in a protein sequence can be related to a number of pathological conditions of dramatic social impact such as Alzheimer's, Parkinson's and Creutzfeldt-Jakob's diseases. The quality and completeness of presently available SNPs databases allows the application of machine learning techniques to predict the insurgence of human diseases due to single point protein mutation starting from the protein sequence. RESULTS: In this paper, we develop a method based on support vector machines (SVMs) that starting from the protein sequence information can predict whether a new phenotype derived from a nsSNP can be related to a genetic disease in humans. Using a dataset of 21 185 single point mutations, 61% of which are disease-related, out of 3587 proteins, we show that our predictor can reach more than 74% accuracy in the specific task of predicting whether a single point mutation can be disease related or not. Our method, although based on less information, outperforms other web-available predictors implementing different approaches. AVAILABILITY: A beta version of the web tool is available at http://gpcr.biocomp.unibo.it/cgi/predictors/PhD-SNP/PhD-SNP.cgi

Algorithms↗
PubMed2006

Oral vinorelbine plus capecitabine (oral vincap) combination in patients with advanced breast cancer (ABC). A phase II study of the GOIM (Gruppo Oncologico dell'Italia Meridionale).

BACKGROUND: Vinorelbine i.v. and capecitabine are two of the most effective single agents in previously treated advanced breast cancer (ABC). A number of studies have been reported with the combination of these agents. Actually, the availability of oral formulation for vinorelbine allows a full oral combination of the two agents. The aim of this study was to evaluate the activity and toxicity of this novel combination. PATIENTS AND METHODS: Thirty-eight advanced breast cancer patients refractory to anthracyclines and taxanes were included in this study. Treatment consisted of vinorelbine 60 mg/m(2) (days 1 + 8), and capecitabine 2000 mg/m(2) (days 2-7 and 9-16) every 3 weeks. RESULTS: A total of 228 courses were given with a mean of three cycles/patient (range 1-12). Five patients (13.1%) had no toxicity at all. Hematologic side-effects were: neutropenia grade 2-3 in seven patients (18.9%) and grade 4 in one patient (2.7%), anemia grade 1 in 11 patients (29.7%), grade 2-3 in five patients (13.5%), thrombocytopenia grade 1 in six patients (16.2%) and grade 3 in one patient (2.7%). Non-hematologic side-effects were: fatigue grade 1 in five patients (13.5%), hand-foot syndrome grade 1 in two patients (5.4%) and grade 2 in two patients (5.4%), nausea/vomiting grade 1 in two patients (5.4%), grade 2 in three patients (8.1%) and grade 3 in one patient (2.7%), constipation grade 1 in two patients (5.4%), peripheral neurotoxicity grade 1 in three patients (8.1%) and grade 2 in one patient (2.7%), gastric pain grade 1 in two patients (5.4%), stomatitis grade 1 in three patients (8.1%) and grade 2 in one patient (2.7%). Out of 38 patients assessable, we observed two (5.4%) CR, 13 (34 %) PR, 14 (37.8%) SD and nine (26.3%) PD. The median time to progression was 4.5 months (range 1-18 months), the median response duration was 7 months (range 2-18 months) and the median survival duration was 10 months (range 2-26+). CONCLUSIONS: The oral vincap should be considered as an alternative to single agent capecitabine or vinorelbine in ABC refractory to antra-taxane combination.

Administration, Oral↗
PubMed2006

[Duodenal angiodysplasia and Turner's syndrome. Case report].

UNLABELLED: The Turner's syndrome is the most common chromosomic disease in the women and touches 1:2,500 women born live. The most important anomaly is the presence of short stature and ovarian failure. Others disorders are increasing in case reports: osteoporosis, hypothyroidism, renal diseases and gastroenteric diseases. The Authors, after careful review of the literature, that proves rarity of the disease, report a case of duodenal vascular anomaly associated with Turner's syndrome and describe surgical therapy, peculiar to this atypical localization. CASE REPORT: A 31 years old woman, genotypic XO and female phenotypic, with diabetes mellitus type I, arterial hypertension and hypertransaminasemia. Since three days the patient reports epigastric pain discontinuous, not widespread, not nocturnal, with wretch, bowel open only to gas. The patient underwent Rx abdomen, Rx with gastrografin, TC abdomen. Diagnosed as a high digestive occlusion, the patient underwent explorative laparotomy. As laparotomy she had a necrotic-hemorrhagic lesion in duodenum D3-D4 and first jejunal loop, with stenosis of the jejunal lumen, perforation of serosa and blood in peritoneal cavity. Resection of necrotic loop and reconstruction with Y loop performing manual duodenum jejunal L-L anastomosis, mechanical gastroenterostomy and enteric-enteric L-L mechanical anastomosis. After operation hemorrhage from anastomosis was observed, treated with omeprazole therapy and total parenteral nutrition. The patient was discharged in 14th p. o. day. After two years she is in good health without gastrointestinal symptoms. In patients with Turner's syndrome gastrointestinal vascular anomalies have to be considered as diagnostic hypothesis in cause of abdominal pain.

Adult↗
PubMed2003

Interference study of the chi c0(13P0) in the reaction -pp-->pi0pi0.

Fermilab experiment E835 has observed (-)pp annihilation production of the charmonium state chi(c0) and its subsequent decay into pi(0)pi(0). Although the resonant amplitude is an order of magnitude smaller than that of the nonresonant continuum production of pi(0)pi(0), an enhanced interference signal is evident. A partial wave expansion is used to extract physics parameters. The amplitudes J=0 and 2, of comparable strength, dominate the expansion. Both are accessed by L=1 in the entrance (-)pp channel. The product of the input and output branching fractions is determined to be B((-)pp-->chi(c0))xB(chi(c0)-->pi(0)pi(0))=(5.09+/-0.81+/-0.25)x10(-7).

Journal Article↗
PubMed2002

Contrast-enhanced three-dimensional MR angiography of neck vessels: does dephasing effect alter diagnostic accuracy?

The aim of this study was to evaluate diagnostic accuracy of contrast-enhanced MRA (CEMRA) compared with digital subtraction angiography (DSA) in studying neck vessels of 48 patients. In three groups of patients, we used three MRA protocols differing for voxel size to assess if intravoxel dephasing effects could modify accuracy of CEMRA. Accuracy and correlation with DSA results were calculated in all patients and separately in the three groups. A qualitative analysis of the likeness between morphology of the stenosis in CEMRA and DSA images was also assessed. In all patients accuracy and agreement with DSA were 96% and k=0.85 in subclavian arteries, 96% and k=0.84 in vertebral artery, 97% and k=0.88 in common carotid arteries, and 94% and k=0.86 in internal carotid arteries. In the three groups accuracy and agreement with DSA did not show any significant difference. Qualitative analysis of CEMRA and DSA images revealed a better agreement in depicting the morphology of stenosis using a smaller voxel size. The CEMRA represents a powerful tool for the non-invasive evaluation of neck vessels. Overestimation trend of CEMRA is confirmed and the reduction of voxel size, decreasing the dephasing intravoxel effect, allows to have a better overlapping of stenosis morphology on CEMRA compared with DSA, but it does not yield diagnostic gain in the stenosis grading.

Aged↗
PubMed2002

Risk factors for Aujeszky's-disease seropositivity of swine herds of a region of northern Italy.

Vaccination programs to control Aujeszky's-disease virus (ADV) using gE-deleted vaccines are being considered in several European countries. Knowledge of factors influencing ADV-seropositivity for vaccinated herds might contribute to the success of these programs. A multivariable analysis of ADV-seropositivity in 1248 swine herds (332 farrow-to-finish, 260 farrow-to-feeder and 656 finishing herds) in the Emilia-Romagna region of Italy revealed that (1) high pig density (number of pigs in a 6-km radius), (2) gilt purchasing, and (3) increased number of fattening pigs were risk factors for farrow-to-finish herds. In farrow-to-feeder herds, ADV-seropositivity was related to (1) increased number of breeders, (2) heavy-gilt purchasing, and (3) increased pig density. In finishing herds, (1) increased herd size was related to ADV-seropositivity, whereas (2) periodic rearing suspension was protective.

Animal Husbandry↗
PubMed2001

Explosive vaporization of metallic sodium microparticles by CW resonant laser radiation.

Explosive vaporization of metallic Na microparticles stimulated by resonant cw laser radiation has been observed in a glass cell. Vaporization occurs at low laser-power density. The effect consists in the generation of optically thick and sharply localized Na vapor clouds propagating in the cell against the laser beam. The effect is explained by laser excitation of Na atoms, which collide onto the surface of the microparticles and transfer their internal energy. This causes other atoms to be vaporized and to continue the avalanche process.

Journal Article↗
PubMed2001

Nitric oxide (NO) modulation of PAF-induced cardiopulmonary action: interaction between NO synthase and cyclo-oxygenase-2 pathways.

1. To further investigate into the mechanisms of PAF-induced cardiopulmonary actions, we examined the effects of the nitric oxide synthase (NOS) inhibitor L-N(omega)-nitro-L-arginine (L-NNA), of the specific cyclooxygenase-2 (COX-2) inhibitor NS 398, and of the combined presence of both COX and NOS inhibitors on the PAF responses in the heart lung preparation of guinea-pig (HLP). 2. In HLPs perfused with homologous blood, dose-response curves for the haemodynamic and bronchial effects of PAF (1 - 32 ng) were carried out in the absence or presence of L-NNA (200 microM). L-NNA caused an increase in the resting pulmonary arterial pressure (PAP) without affecting the other basal values, and strongly potentiated the bronchoconstriction and pulmonary hypertension elicited by PAF. An enhancement of the PAF-induced actions on right atrial pressure (RAP) and cardiac output (CO) was also observed. All the effects of L-NNA were antagonized by L-arginine (2 mM). 3. The presence of L-NNA in the perfusing blood of HLPs failed to affect the pulmonary hypertensive and bronchoconstrictor responses induced by the thromboxane A(2) mimetic U46619 (0.05 - 1.6 microg), 5-hydroxytryptamine (0.1 - 1.6 microg), and histamine (0.1 - 1.6 microg), thus suggesting that these PAF secondary mediators are not responsible for the hyper-responsiveness to PAF induced by L-NNA. 4. Blocking COX-2 pathway with NS 398 (15 - 30 microM) did not alter the cardiopulmonary resting variables. However, a reduction of the PAF-mediated pulmonary hypertension, but not of bronchoconstriction, was observed. When L-NNA was added to the perfusing medium of HLPs pre-treated with NS 398 or with indomethacin (15 microM), the basal PAP values were enhanced. However, in the combined presence of COX and NOS inhibitors, only a slight increase in the hypertensive responses to the highest doses of PAF was observed, whereas the PAF mediated actions at bronchial and cardiac level were unaffected. 5. This study indicates that (i) the cardiopulmonary actions induced by PAF are specifically modulated by endogenous NO through the NOS pathway, and (ii) COX-2 isoform is involved in the pulmonary hypertensive, but not bronchoconstrictor, effects of PAF. Furthermore, an interaction between PAF stimulated COX, particularly COX-2, and NOS pathways appears to take a functional role at both bronchial and cardiovascular level.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1998

[Post-cholecystectomy syndrome: hepatobiliary scintigraphy and cholangiopancreatography with magnetic resonance in 5 consecutive patients. Comparison of results and integrated diagnosis].

PURPOSE: To investigate the clinical effectiveness of combined hepatobiliary scintigraphy (HBS) and MR-cholangiopancreatography (MRCP) studies in the postcholecystectomy syndrome. MATERIAL AND METHODS: June 1997, to February 1998, we examined with HBS and MRCP five women, three of them submitted to surgical and two to laparoscopic cholecystectomy. All patients had biliary pain but no changes in cholestasis and liver function blood parameters. After at least 4 hours' fasting HBS was performed dynamically, for one hour, injecting a 185 MBq 99mTc-mebrofenin bolus i.v. A fatty meal was given at the end of the basal test and serial static images were acquired till complete biliary washout. RESULTS: MRCP was normal in one case while in the others it showed biliary tree dilation, severe stricture of the distal common bile duct (CBD) and marked enlargement of the remnant cystic duct (RCD), which lodged a 6-mm stone in one patient. Pancreatic ducts were regular. HBS showed delayed biliary transit in all patients, which was however completed within 3 hours of injection, favored by the fatty meal. The RCD was not injected in three cases. Finally, HBS detected an early liver dysfunction in three cases. DISCUSSION: HBS and MRCP allow to evaluate the biliary tree function and anatomy, respectively, adding further data on liver function and pancreatic duct morphology. We detected associated functional and organic biliary alterations which were the likely cause of postcholecystectomy pain, such as severe spasm in Oddi's sphincter, nonpatent enlarged RCD and RCD stones. Moreover, HBS detected an early liver dysfunction in three cases. In conclusion, combined HBS and MRCP studies make a noninvasive, simple and accurate diagnostic approach in postcholecystectomy syndrome and for the screening of patients needing prompt surgical treatment.

Aged↗
PubMed1997

Case report. MRI and MR angiography of basilar artery dissection in a child.

MRI showed a pontine infarct and mural thickening of intermediate signal in T1-weighted images proximal to occlusion of the basilar artery in a 10-year-old boy. Two days later the mural thickening was of high signal, consistent with methaemoglobin formation and MR angiography (MRA) showed nonspecific lack of flow in the mid-segment of the basilar artery, which corresponded to a tapered occlusion at arteriography. MRI is more useful than MRA for noninvasive diagnosis of basilar artery dissection.

Aortic Dissection↗
PubMed1996

ETB receptor mediating pulmonary hypertension and bronchoconstriction induced by endothelin-1 in the guinea pig.

Endothelin (ET-1) caused dose-related contraction of isolated superfused bronchus and pulmonary artery and bronchoconstriction and pulmonary vascular hypertension of the heart lung preparation (HLP) of guinea pig. The specific ETA receptor antagonist BQ 123 completely blocked the responses of the pulmonary artery, but failed to affect those of bronchus and of HLPs. The specific ETB receptor agonist Sarafotoxin S6c caused contractions of bronchus, but not of pulmonary artery, and bronchoconstriction and pulmonary hypertension in HLPs. It is concluded that non-ETA subtype receptors, perhaps ETB, appear to be the main responsible for the potent pulmonary hypertensive effects of ET-1.

Animals↗