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Showing papers by "University of Palermo published in 1995"



Journal ArticleDOI
TL;DR: For maintenance treatment of reflux esophagitis, omeprazole alone or in combination with cisapride is more effective than ranitidine alone or cisap Ride alone, and the combination of omepazole and cisap ride is moreeffective than ran itidine plus cisapide.
Abstract: Background Patients with reflux esophagitis have a high rate of relapse within one year after therapy is discontinued. Methods We enrolled 175 adults with endoscopy-confirmed reflux esophagitis in a prospective study comparing five maintenance therapies. All the patients were initially treated with omeprazole (40 mg orally once a day) for four to eight weeks, and healing was confirmed by endoscopy. Participants were then stratified according to their initial grade of esophagitis and randomly assigned to 12 months of treatment with one of the following: cisapride (10 mg three times a day), ranitidine (150 mg three times a day), omeprazole (20 mg per day), ranitidine plus cisapride, or omeprazole plus cisapride. Endoscopy was repeated after 6 and 12 months of treatment; the endoscopists were blinded to the treatment assignments. Remission was defined as the absence of esophageal lesions on scheduled or unscheduled follow-up endoscopy. Results In an intention-to-treat analysis, the numbers of patients in con...

512 citations


Journal ArticleDOI
TL;DR: High proportion of patients with HBsAg‐positive compensated cirrhosis do not experience worsening of their condition for several years, but once decompensation occurs life expectancy is poor, and European, white patients with compensated Cirrhosis type B are at consistent risk for HCC.

396 citations


Journal ArticleDOI
TL;DR: By evolving neural controllers for a Khepera robot in computer simulations and then transferring the agents obtained to the real environment, it is shown that an accurate model of a particular robot-environment dynamics can be built by sampling the real world through the sensors and the actuators of the robot.
Abstract: The problem of the validity of simulation is particularly relevant for methodologies that use machine learning techniques to develop control systems for autonomous robots, as, for instance, the artificial life approach known as evolutionary robotics. In fact, although it has been demonstrated that training or evolving robots in real environments is possible, the number of trials needed to test the system discourages the use of physical robots during the training period. By evolving neural controllers for a Khepera robot in computer simulations and then transferring the agents obtained to the real environment we show that (a) an accurate model of a particular robot-environment dynamics can be built by sampling the real world through the sensors and the actuators of the robot; (b) the performance gap between the obtained behaviors in simulated and real environments may be significantly reduced by introducing a "conservative" form of noise; (c) if a decrease in performance is observed when the system is transferred to a real environment, successful and robust results can be obtained by continuing the evolutionary process in the real environment for a few generations.

365 citations


Journal ArticleDOI
TL;DR: Surgery and percutaneous ethanol injection improve survival in single hepatocellular carcinoma associated with Child A and B cirrhosis compared to untreated patients in the same Child class.

278 citations


Journal ArticleDOI
TL;DR: In this paper, a multivariate analysis based on Cox's proportional hazards regression model was performed on the most important prognostic factors and their association with invasion and death, an index was computed reflecting the risk of both invasion and malignant disease, respectively.

276 citations


Journal ArticleDOI
TL;DR: It is concluded that enhanced TXA2 biosynthesis in type IIa hypercholesterolemia is, at least in part, dependent on abnormal cholesterol levels and/or other simvastatin-sensitive mechanisms affecting platelet function.
Abstract: Thromboxane A2 (TXA2) biosynthesis is enhanced in the majority of patients with type IIa hypercholesterolemia. Because simvastatin (a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor) was previously shown to reduce platelet aggregation and TXB2 production ex vivo, we investigated TXA2 biosynthesis and platelet function in 24 patients with type IIa hypercholesterolemia randomized to receive in a double-blind fashion simvastatin (20 mg/d) or placebo for 3 months. The urinary excretion of 11-dehydro-TXB2, largely a reflection of platelet TXA2 production in vivo, was measured by a previously validated radioimmunoassay technique. Blood lipid levels and urinary 11-dehydro-TXB2 excretion were significantly (P < .001) reduced by simvastatin. In contrast, placebo-treated patients did not show any statistically significant changes in either blood lipids or 11-dehydro-TXB2 excretion. The reduction in 11-dehydro-TXB2 associated with simvastatin was correlated with the reduction in total cholesterol (r = .81, P < .0001), LDL cholesterol (r = .79, P < .0001), and apolipoprotein B (r = .76, P < .0001) levels. Platelets from patients with type IIa hypercholesterolemia required significantly (P < .01) more collagen and ADP to aggregate and synthesized less TXB2 in response to both agonists after simvastatin therapy. Bleeding time, platelet sensitivity to Iloprost, and blood lipoprotein(a) and HDL cholesterol levels were not significantly affected by either treatment. We conclude that enhanced TXA2 biosynthesis in type IIa hypercholesterolemia is, at least in part, dependent on abnormal cholesterol levels and/or other simvastatin-sensitive mechanisms affecting platelet function.

256 citations


Journal ArticleDOI
TL;DR: In this paper, a new theoretically based relationship is proposed for evaluating the sediment delivery ratio, SDRi, of each morphological unit, i, into which a basin is divided.
Abstract: Since eroded sediments are produced from different sources distributed throughout a basin, sediment delivery processes at basin scale have to be modelled by a spatially distributed approach. In this paper a new theoretically based relationship is proposed for evaluating the sediment delivery ratio, SDRi, of each morphological unit, i, into which a basin is divided. Then, using the sediment balance equation written for the basin outlet, a relationship between the basin sediment delivery ratio, SDRW and the SDRi is deduced. This relationship is shown to be independent of the soil erosion model used. Finally, a morphological criterion for estimating a coefficient, β, is proposed.

244 citations


Journal ArticleDOI
TL;DR: In this article, x-ray photoelectron spectroscopy (XPS) analysis was performed on pumice-supported nickel catalysts, which were prepared by the method of slow homogeneous precipitation with urea.
Abstract: Pumice-supported nickel catalysts, prepared by the method of slow homogeneous precipitation with urea, were analysed by x-ray photoelectron spectroscopy (XPS). By comparison with similarly prepared silica- and alumina-supported nickel catalysts, a preferential interaction of Ni2+ with Al3+ of the support has been determined. A quantitative XPS analysis indicated large segregation of nickel to the surface. The treatment with H2 at 673 K and 1073 K produced a partial reduction of Ni+2 to Ni0. The extent of the reduction was largest at 1073 K and in this case the reduced Ni in the metallic phase was detectable by x-ray diffraction. A decrease of the Ni 2p/Si 2p intensity ratio occurring in the lower temperature H2-treated catalysts was attributed to diffusion of nickel as Ni2+, as a consequence of a solid-state reaction between nickel ions and support oxides, whereas the decrease of the intensity ratio in the high-temperature reduced catalysts was attributed to sintering of the nickel particles and to diffusion of nickel atoms interacting with oxygen vacancies of the support.

154 citations


Journal ArticleDOI
TL;DR: These results confirm the high prevalence of adverse reactions to foods in diarrheic irritable bowel syndrome and the usefulness of cromolyn sodium treatment in these patients.
Abstract: Background: In a significant number of patients affected by the irritable bowel syndrome, an adverse reaction to food is proposed to be a causative factor. A diet that eliminates the offending food...

146 citations


Journal ArticleDOI
TL;DR: The prevalence of migraine headaches in males was constant through the ages studied, whereas the prevalence of migraines in females reached a peak at age 12 and plateaued over the following two years.
Abstract: We assessed the prevalence of migraine headaches in an epidemiological survey of an 11 to 14-year-old student population. Migraine headaches were classified on the basis of questionnaires and neurological examination using the operational diagnostic criteria of the International Headache Society. Prevalence of migraine without aura (IHS code 1.1) was 2.35%; that of migraine with aura (IHS code 1.2) was 0.62%. Migraine without aura was equally distributed among males and females, whereas migraine with aura was preponderant in the female cohort. The prevalence of migraine headaches in males was constant through the ages studied, whereas the prevalence of migraine headaches in females reached a peak at age 12 and plateaued over the following two years. Although the new IHS classification criteria of migraines are reliable and exhaustive, some subcriteria may not be valid in a juvenile population. For instance, the duration of the pain in young migraineurs is often briefer than in adults, and the intensity of pain was almost always described as moderate or severe. Therefore, in order to increase the reliability and comprehensiveness of the IHS classification, minor modifications should be made.

Journal ArticleDOI
TL;DR: Experiments carried out with exogenous PGE2 indicated that concentrations between 1 and 10 ng/mL are able to stimulate the expression of NOS and the release of NO, while higher concentrations (> 50 ng/ mL) are inhibitory.

Journal ArticleDOI
TL;DR: The fluoro-quinolone-loaded nanoparticles showed an enhancement of the antimicrobial activity against standard bacteria strains from 2- to 50-fold compared with the free drugs.

Journal ArticleDOI
TL;DR: It is concluded that constipation in infants with chronic "idiopathic" constipation may have an allergic pathogenesis.

Journal Article
TL;DR: Obesity with body fat distribution of central type, more than obesity of peripheral type, is associated to abnormalities in renal haemodynamics and function, consistent with the indication that change in renalHaemodynamics take place at an early stage in the obesity-induced hypertension.
Abstract: OBJECTIVE : To investigate the role of alterations in renal haemodynamics and function and in plasma renin activity on obesity-induced hypertension. DESIGN : Renal haemodynamics and function, salt-regulating hormones and structural cardiac parameters were evaluated in 20 lean normotensives and in 64 obese subjects with central or peripheral fat distribution, 43 of them were normotensives and 21 of them were hypertensives. Obesity and central fat distribution were defined according to sex-specific 85th percentile respectively of Body Mass Index (BMI) and Waist to Hip Ratio (WHR). MEASUREMENTS : Serum immunoreactive insulin (IRI), plasma renin activity (PRA), plasma aldosterone (PA), microalbuminuria (UAE) and 24h urinary excretion of sodium (NaU) were evaluated by current methods. Renal haemodynamics was evaluated by radionuclide study according to Schlegel's and Gate's methods. By radionuclide study, effective renal plasma flow (ERPF), effective renal blood flow (ERBF), glomerular filtration rate (GFR), filtration fraction (FF) and renal vascular resistances (RVR) were measured. Left ventricular mass (LVM) and indexed for body height (LVM/H), cardiac output (CO) and total peripheral resistances (TPR) by ecocardiography were also calculated. RESULTS : CO, LVM and LVM/H were significantly (P < 0.05) higher in all the obese groups than lean controls. In addition, LVM and LVM/H were significantly (P < 0.05) higher in obese hypertensives than obese normotensives either with central fat distribution. TPR values were significantly (P < 0.05) higher in central obese hypertensives than peripheral obese hypertensives and than central obese normotensives. Moreover, IRI levels were significantly (P < 0.05) higher in central normotensive and hypertensive obese subjects than lean subjects. ERBF and ERPF were significantly (P < 0.05) lower and PRA levels were significantly higher only in central obese than lean subjects. On the contrary RVR were significantly (P < 0.05) higher in both obese hypertensive groups and in central obese normotensives than lean subjects. Comparisons between peripheral and central obese groups indicated that PRA, RVR and UAE were significantly (P < 0.05) higher and ERBF and ERPF values were significantly (P < 0.05) lower in both central obese groups than comparable subjects with peripheral obesity. Multiple regression analysis indicated that RVR increased significantly (P < 0.05) with WHR and PRA but not with CO and IRI. CONCLUSIONS : Our results indicate that obesity with body fat distribution of central type, more than obesity of peripheral type, is associated to abnormalities in renal haemodynamics and function. These data are consistent with the indication that change in renal haemodynamics take place at an early stage in the obesity-induced hypertension.

Journal ArticleDOI
TL;DR: Results suggest that OrfX plays a direct role in the regulation of the dnaK operon, a novel heat‐shock gene of Streptomyces coelicolor A3(2) that is contained within a 4.3 kb operon.
Abstract: Transcriptional studies have demonstrated that the dnaK gene of Streptomyces coelicolor A3(2) is contained within a 4.3 kb operon. The operon is transcribed from a single (transiently) heat-inducible promoter, dnaKp, that resembles the typical vegetative (sigma 70-recognized) eubacterial consensus promoter sequence. dnaK transcription was found to be heat-inducible at all stages of development in surface-grown cultures. In addition, at the normal growth temperature of 30 degrees C, dnaK transcript levels were shown to vary at different stages of development, being more abundant in young germinating cultures and in mycelium undergoing sporogenesis. The nucleotide sequence of the dnaK operon has been completed, revealing the gene organization 5'dnaK-grpE-dnaJ orfX. orfX represents a novel heat-shock gene. Its predicted product displays high similarity to the GlnR repressor proteins of Bacillus spp. and to the MerR family of eubacterial transcriptional regulators. The S. coelicolor OrfX protein has been over-produced in Escherichia coli, and DNA-binding experiments indicate that it interacts specifically with the dnaKp region, binding to three partially related inverted repeat sequences; they are centered at -75, -49 and +4, respectively, relative to the transcription start site of the operon. These results suggest that OrfX plays a direct role in the regulation of the dnaK operon.

Journal ArticleDOI
TL;DR: In this article, wide variations were measured in the diffuse CO2 flux through the soils in three selected areas of Mt Etna between August 1989 and March 1993, and the highest fluxes measured in two most peripheral areas may correlate well with other geophysical and volcanological anomalous signals that preceded the strong eruption of 1991-1993 and that were interpreted as deep pressure increases.
Abstract: Wide variations were measured in the diffuse CO2 flux through the soils in three selected areas of Mt Etna between August 1989 and March 1993. Degassing of CO2 from the area of Zafferana Etnea-S. Venerina, on the eastern slope of the volcano, has been determined to be more strongly influenced by meteorological parameters than the other areas. The seasonal component found in the data from this area has been excluded using a filtering algorithm based on the best fitting equation calculated from the correlation between CO2 flux values and those of air temperature. The filtered data appear to have variations temporally coincident with those from the other areas, thus suggesting a common and probably deep source of gas. The highest fluxes measured in the two most peripheral areas may correlate well with other geophysical and volcanological anomalous signals that preceded the strong eruption of 1991–1993 and that were interpreted as deep pressure increases. Anomalous decreases in CO2 fluxes accompanied the onset and the evolution of that eruption and have been interpreted as a sign of upward migration of the gas source. The variations of CO2 flux at the 1989 SE fracture have also given interesting information on the timing of the magmatic intrusion that has then fed the 1991–1993 eruption.

Journal ArticleDOI
TL;DR: In this article, the authors measured cytosolic free calcium in primary cultures of vascular smooth muscle cells isolated from Sprague-Dawley rat tail artery before and after incubation with 5 (basal), 10, 15, and 20 mM glucose.
Abstract: We have previously suggested that hyperglycemia per se may contribute to diabetic hypertensive and vascular disease by altering cellular ion content. To more directly investigate the potential role of glucose in this process, we measured cytosolic free calcium in primary cultures of vascular smooth muscle cells isolated from Sprague-Dawley rat tail artery before and after incubation with 5 (basal), 10, 15, and 20 mM glucose. Glucose significantly elevated cytosolic free calcium in a dose- and time-dependent manner, from 110.0 +/- 5.4 to 124.5 +/- 9.0, 192.7 +/- 20.4, and 228.4 +/- 21.9 nM at 5, 10, 15, and 20 mM glucose concentrations, respectively. This glucose-induced cytosolic free calcium elevation was also specific, no change being observed after incubation with equivalent concentrations of L-glucose or mannitol. This glucose effect was also dependent on extracellular calcium and pH, since these calcium changes were inhibited in an acidotic or a calcium-free medium, or by the competitive calcium antagonist lanthanum. We conclude that ambient glucose concentrations within clinically observed limits may alter cellular calcium ion homeostasis in vascular smooth muscle cells. We suggest that these cellular ionic effects of hyperglycemia may underlie the predisposition to hypertension and vascular diseases among diabetic subjects and/or those with impaired glucose tolerance.

Journal ArticleDOI
01 Oct 1995-Cytokine
TL;DR: In Sicilian patients with active VL the cytokine profile is not clearly characterized by Th2 phenotype as in mice, and both Th1-like and Th2-like cells appear to proliferate and to be activated.

Journal ArticleDOI
TL;DR: In this paper, different preparation conditions have been able to influence the final PECA nanocapsule colloidal suspension, such as interfacial precipitation of a pre-formed polymer and the interfacial polymerization, and other variables such as the kind of the nonionic surfactant and the monomer concentration, affected in different ways the nanocapule formation process.


Journal Article
TL;DR: It is demonstrated that IL-4 is an essential cytokine at the effector stage of the CS reaction, as inhibition of its production or action blocked the passive transfer of CS.
Abstract: This study demonstrates an essential role for interleukin-4 (IL-4) in the delayed hypersensitivity reaction, as illustrated by contact sensitivity (CS) to trinitrochlorobenzene (TNCB). Injection of mice with monoclonal antibody to IL-4, but not with control antibody, reduced CS after active immunization by 75%, as judged by ear swelling. The histological alterations of CS were also reduced. IL-4 was essential to the effector stage, as inhibition of its production or action blocked the passive transfer of CS. In particular, treatment of immune lymph node cells with antisense oligonucleotide to IL-4 inhibited the systemic transfer of CS. Transfer was also inhibited by monoclonal antibody to IL-4 given to the recipient. The present results indicate that IL-4 is an essential cytokine at the effector stage of the CS reaction.

Journal ArticleDOI
TL;DR: In this paper, the authors studied the signal-to-noise ratio, signal and noise output levels in a fast bistable electronic system: a tunnel diode, and observed stochastic resonance when the system is driven by a sum of a small periodic signal and the noise.
Abstract: We study the signal-to-noise ratio, signal and noise output levels in a fast bistable electronic system: a tunnel diode. We observe stochastic resonance when the system is driven by a sum of a small periodic signal and noise. The phenomenon is investigated for values of the driving frequency as high as 10 kHz. This is the highest frequency value used in SR experiments until now. In the presence of «white noise», we observe a nonmonotonic behavior characterized by a sharp dip in the output noise level measured at 100Hz and 1 kHz. A similar behavior is predicated by recent theories. We also present preliminary experimental results of SR in the presence of an Ornstein-Uhlenbeck noise. For the set of investigated values of the correlation time of the noise, we still observe the characteristic dip in the output noise levels. The height of the dip is affected by the correlation time of the noise.

Journal ArticleDOI
TL;DR: Chemical stability studies in pH 1.1 buffer solution have shown that linking O-succinylacyclovir to PHEA increases the stability of the free drug even more than the succinic derivative.

Journal ArticleDOI
TL;DR: The data show that PTHrP [1-34], and, to a minor extent, [67-86] and [107-139], are anti-mitogenic but 'invadogenic' for 8701-BC cells, and suggest that diverse enzymatic activities may contribute to cell invasion in response to different P THrP fragments.

Journal ArticleDOI
TL;DR: The data suggest that obesity-associated hypertension is characterized by an endothelial dysfunction that may contribute to the higher cardiovascular risk detectable in these patients.

Journal ArticleDOI
TL;DR: Methods introduced here to analyse the response of groups of genes to multiple simultaneous stimuli should find broad applications to studies of other prokaryotic and eukaryotic regulons.
Abstract: In the differentiating eubacterium Streptomyces coelicolor, nutritional imbalances activate a developmental programme which involves the heat-shock stress regulon. In liquid batch cultures, the growth curve could be separated into four components: rapid growth 1 (RG1), transition (T), rapid growth 2 (RG2) and stationary (S). Patterns of gene expression in cultures subjected to heat shock in various phases were recorded on two-dimensional gels and analysed using advanced statistical methods. The responses of all heat-shock proteins (HSPs) were highly dependent upon the growth phase, thus demonstrating that the four phases of growth were physiologically distinct. For many HSPs, the levels of thermal induction attained were closely related to growth stage-determined levels of synthesis before heat shock, thus supporting the idea that developmental and thermal induction of this stress regulon have common control elements. Cluster analysis identified five groups of HSPs displaying similar kinetics of heat and developmentally induced synthesis, probably reflecting the influence of major regulatory systems. Methods introduced here to analyse the response of groups of genes to multiple simultaneous stimuli should find broad applications to studies of other prokaryotic and eukaryotic regulons.

Journal ArticleDOI
TL;DR: The data suggest that tumor markers detected in the circulation of carcinoma patients, at least in part, are carried by shed membrane vesicles, and suggest an important role for vesicle in the immunological escape of these cells.
Abstract: We have compared the pattern of surface antigen expression, as detected by monoclonal antibodies (mAbs), in plasma membranes vs shed membrane vesicles of two human breast carcinoma cell lines, MCF-7 and 8701-BC. Antigen expression was detected on cells by immunofluorescence (IF) analysis, whilst, due to their small dimensions, the same technique was not applicable to vesicles. For these structures dot-blot analysis and immunoelectron microscopy (IEM) were employed. When applicable, both cell membranes and membrane vesicles were immunoprecipitated and the precipitate (IP) was analyzed by SDS-PAGE. Cells of both lines expressed HLA class I antigens, epithelial cytokeratins, β1 integrins, CEA and the glycoprotein detected by mAb 19.9, but only MCF-7 cells expressed Lewis Y, episialin and globo-H antigens and only 8701-BC cells expressed folate receptor. Membrane vesicles of both cell lines appeared to be rich in β1, α3 and α5 integrin chains, expressed HLA class I antigens and carried most of the plasma membrane antigens found in the cell membranes. Overall we have analyzed 17 antigens on the two cell lines and on their vesicles. The results obtained for cells (IF and IP) and those for vesicles (dot-blot and IP) were generally concordantly positive or concordantly negative. We obtained a total of 26 clearly concordant combinations on 34 analyses. In three cases we found discordant results, whereas in the remaining combinations we observed slight reactivity and we found difficulties in determining concordance. Discordant results concerned the expression of the following antigens: folate receptors, which were clearly expressed in 8701-BC cells but not detected by dot-blot analysis or IEM on their shed membrane vesicles; neu (c-erb-B2) receptor found in MCF-7 cell membranes but not in their vesicles; and the globo-H antigen recognized by mAb MBr1, detected at low levels on 8701-BC plasma membranes but undetectable on their membrane vesicles. Like vesicles shed in vitro by cultured cells, the vesicles shed in vivo by human breast carcinoma cells could be tagged with several antibodies against tumor-associated antigens. The vesicles shed in vivo were found in association with a fiber network. Some of the fibers had the characteristic fibrin periodicity. These data suggest that tumor markers detected in the circulation of carcinoma patients, at least in part, are carried by shed membrane vesicles. Moreover the observation that membrane vesicles carry both tumor-associated antigens and HLA class I molecules indicate that these structures could in principle present antigens to the immune system. Together with our previous demonstration that membrane vesicles shed by breast carcinoma cells contain TGF-β, these results suggest an important role for vesicles in the immunological escape of these cells. The presence in membrane vesicles of integrins, together with the previous observation that they are rich in gelatinolytic activities, also points to a possible role of these structures in the metastatic behavior of tumor cells.

Journal ArticleDOI
TL;DR: In this paper, the exact stationary solution in terms of probability density function for a restricted class of nonlinear systems under both external and parametric non-normal delta-correlated processes is presented.
Abstract: In this paper the exact stationary solution in terms of probability density function for a restricted class of non-linear systems under both external and parametric non-normal delta-correlated processes is presented. This class has been obtained by imposing a given probability distribution and finding the corresponding dynamical system which satisfies the modified Fokker-Planck equation. The effectiveness of the results has been verified by means of a Monte Carlo simulation.

Journal ArticleDOI
G. Agrò1
TL;DR: In this article, the problem of obtaining maximum likelihood estimates for the three parameters of the exponential power function is addressed, and the information matrix is derived and the covariance matrix is presented; the regularity conditions which ensure asymptotic normality and efficiency are examined.
Abstract: This paper addresses the problem of obtaining maximum likelihood estimates for the three parameters of the exponential power function; the information matrix is derived and the covariance matrix is here presented; the regularity conditions which ensure asymptotic normality and efficiency are examined. A numerical investigation is performed for exploring the bias and variance of the maximum likelihood estimates and their dependence on sample size and shape parameter.