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Biomedical subjects

A D'Onofrio

Publications and source records attributed to A D'Onofrio.

At least 19 recordsLinked to original sources

Peyronie's disease: lights and shadows.

Peyronie's disease (PD) is characterized by the onset of fibrous plaque inside the tunica albuginea of the penile corpora cavernosa that can cause pain and bending during the erection, making intercourse difficult or impossible. Evidence of the literature supports the autoimmune etiology of PD and suggests genetic and familiar conditions, penile traumatisms, and a history of genital tract diseases as risk factors, but no definitive conclusions arise about the pathogenesis of the disease. Few randomized trials demonstrated that medical therapies, such as vitamin E, colchicine, potassium aminobenzoate, tamoxifen, and injection therapy with verapamil, can stabilize the acute phase of the disease. Extracorporeal shock wave therapy and iontophoresis cannot be considered first-line or gold standard therapies. Satisfactory results have been published with the Nesbit operation in large series with low-stage disease, whereas plication procedures have shown significant relapse rates. A high incidence of long-term penile retractions has been reported in high-stage disease treated with plaque incision and simple graft insertion. Malleable, soft, or inflatable prostheses combined with graft implantation have given the best results in terms of penile straightening and lengthening and patient satisfaction. In conclusion, the etiopathogenesis of PD is not yet clearly understood, no medical therapy is fully effective, and surgery remains the gold standard in patients with severe deformity and/or erectile dysfunction.

Antineoplastic Agents↗

Nonlinear fingering dynamics of reaction-diffusion acidity fronts: self-similar scaling and influence of differential diffusion.

Nonlinear interactions between chemical reactions and buoyancy-driven Rayleigh-Taylor instability of reaction-diffusion acidity fronts of the chlorite-tetrathionate (CT) reaction are studied theoretically in a vertical Hele-Shaw cell or a porous medium. To do so, we perform a numerical integration of a two-variable reaction-diffusion model of the CT system coupled through an advection term to Darcy's law ruling the evolution of the velocity field of the fluid. The fingering dynamics of these chemical fronts is characterized by the appearance of several fingers at onset. These fingers then undergo coarsening and eventually merge to form one single symmetric finger. We study this asymptotic dynamics as a function of the three dimensionless parameters of the problem, i.e., the Damkohler number Da, the diffusivity ratio delta of the two chemical species, and the Rayleigh number Ra constructed here on the basis of the width L(y) of the system. For moderate values of Ra, the asymptotic single finger is shown to have self-similar scaling properties while above a given value of Ra, which depends on the other values of the parameters, tip splitting comes into play. Increasing the difference of diffusivities of the two chemical species (i.e., increasing delta) leads to more efficient coarsening and smaller asymptotic fingers. Experimental procedures to verify our predictions are proposed.

Journal Article↗

Optimized sample preparation for isotopic analyses of CO2 in air: systematic study of precision and accuracy dependence on driving variables during CO2 purification process.

A systematic analysis of efficiency, reproducibility and accuracy of cryogenic purification of CO(2) from air samples for isotopic analyses is presented. The technical characteristics of the cryogenic line are given in detail. To study the cryogenic process, three different operating parameters are considered: flow rate of the gas entering the line, pressure of the gas in the line, and CO(2)-trap shape. Experimental results demonstrate that efficiency, reproducibility and accuracy strongly depend on the CO(2)trap shape. Moreover, a dependence of reproducibility and accuracy on the flow rate of the gas is found, but not on its pressure. High precision (< or =0.02 per thousand for delta(13)C and < or =0.05 per thousand for delta(18)O) and good accuracy (<0.09 per thousand for delta(13)C and <0.14 per thousand for delta(18)O) is achieved after applying the N(2)O correction.

Journal Article↗

Transfer of 137Cs and 60Co from irrigation water to a soil-tomato plant system.

An experiment has been performed at the nuclear power plant of Garigliano (Caserta, Italy), aiming at the measurement of transfer factors of 137Cs and 60Co radionuclides from the irrigation water to a soil-plant system, with particular attention to the influence on such transfers of the irrigation technique (ground or aerial). Tomato plants were irrigated weekly with water contaminated with 137Cs and 60Co (about 375 Bq/m2 week), using both irrigation techniques. After 13 weeks, fruits, leaves, stems, roots and soil were sampled, and radionuclide concentrations were measured by high-resolution gamma spectroscopy. It was found that the activity allocated to the plant organs is significantly dependent upon the irrigation technique, amounting to 2.1% and 1.6% of the activity given in the cultivation for aerial treatment and 0.4% and 0.3% for the ground treatment, for 137Cs and 60Co respectively. The activity absorbed by plants is allocated mainly in leaves (> 55%), while less then 10% is stored in the fruits, for both irrigation techniques. Transfer factors (soil-plant and irrigation water-plant) of tomato plants and of weeds have been determined for 137Cs and 60Co, as well as for natural 40K in the soil.

Adsorption↗

A compact multiparameter acquisition system for radon concentration studies

A compact device suitable to acquire and display, at the same time, radon concentrations in a given atmosphere, and the environmental parameters characterising the atmosphere, is presented and described. It consists of two main blocks: (i) a detection section including a set of sensors for measuring pressure, humidity and temperature, and a set of silicon surface barrier detectors mounted in electrostatic cells collecting the ionised radon daughters; (ii) a single NIM module featuring an eight channel 12 bit ADC and the linear electronics to shape the signals from the silicon detectors. The system is controlled by a computer via a RS232 port. The software, implemented in Visual Basic, allows to display the energy distribution of the pulses coming from the alpha detectors and to initialise and control all phases of the acquisition. The results of preliminary tests show the high reliability of the system.

Journal Article↗

A comparison of consumer and provider preferences for research on homeless veterans.

Despite the dramatic growth of homelessness research, there have been no systematic assessments of consumer and provider preferences regarding the content of this research. Therefore, 87 clients and 28 staff of a homeless veterans program were administered a 15-item questionnaire requesting identification of the 5 "most" and 5 "least" important research topics. Staff and clients differed significantly on 6 items considered most important and 4 items considered least important. Clients wanted more research that focused on material needs, whereas staff preferences were more broadly distributed. The fact that appreciable data exist for many of the research topics that respondents identified as important raises concerns about the accessibility of homelessness research.

Attitude↗

Right bundle branch block, persistent ST-segment elevation in V1-V3 and sudden cardiac death: always a distinct syndrome?

Right bundle branch block, persistent ST segment elevation in right precordial leads and sudden cardiac death, unexplainable by currently known disease, define a new distinct clinical and electrocardiographic syndrome. This report describe a patient with these features, whose physical examination, echocardiography, chest computed tomography and right ventricular angiography were normal. However, despite the negativity of these examinations, cardiac nuclear magnetic resonance allowed the identification of right ventricular dysplasia. Thus, right ventricular dysplasia should be considered in the differential diagnosis of the syndrome characterized by right bundle branch block, persistent ST segment elevation and sudden cardiac death.

Adult↗

Flecainide single oral dose for management of paroxysmal supraventricular tachycardia in children and young adults.

The efficacy of a single oral dose of flecainide to terminate paroxysmal supraventricular tachycardia (PSVT) was evaluated in 25 children and young adults. The subjects were selected from a group of 35 patients with recurrent attacks of PSVT evaluated by means of electrophysiologic study and intravenous electropharmacologic testing with flecainide. In all 25 patients the induced PSVT was stopped by intravenous flecainide and was then no longer inducible or nonsustained. All patients had normal hearts. At least 48 hours after acute intravenous testing, 25 patients underwent electrophysiologic study with a transesophageal catheter and PSVT was induced in all of them: atrioventricular reentrant tachycardia in 16 and atrioventricular nodal reentrant tachycardia in nine. During stable tachycardia, a single oral dose of flecainide (2.9 +/- 0.3 mg/kg; 2.5 to 3.3 mg/kg) was administered. This approach was effective for termination of PSVT in 22 patients. The mean plasma level of flecainide at cessation of tachycardia was 277 +/- 92 ng/ml (150 to 500 mg/ml). All 22 patients who responded were given a single oral dose of flecainide for recurrences of PSVT during follow-up. During a period of 12 +/- 7 months (2 to 27 months) a total of 134 spontaneous episodes of PSVT were reported, and 127 of these episodes were terminated with periodic management. Thus oral periodic flecainide seems useful for management of PSVT in selected patients.

Administration, Oral↗

[Transient alkaline hyperphosphatasemia in childhood. A report of 4 clinical cases and etiopathogenetic hypotheses].

The paper reports four cases of idiopathic transient alkaline hyperphosphatasemia during episodes of acute infection of presumable viral etiology. It is interesting to note that one patient present a exanthematous febrile reaction to an anti-measles vaccination, which seems to confirm that the measles virus may be one of the possible causal factors of the pathology. The assay of alkaline phosphatase isoenzymes showed an increase in the three hepatic, bone and intestinal fractions, thus excluding a sectorial pathology (bone or hepatic). This will avoid the need to subject the child to superfluous diagnostic tests in this transient and benign condition of increased enzyme levels.

Alkaline Phosphatase↗

Left posterior fascicular tachycardia due to localized microreentry.

Fascicular tachycardia in young patients without overt heart disease constitutes a rare but electrophysiologically distinct arrhythmia entity. Microreentry within the left posterior fascicle has been proposed as its mechanism, but evidence for this is inconclusive. This report details a patient with incessant fascicular tachycardia. The electrophysiological features, in particular the pattern of resetting response, provided strong evidence for reentry as the tachycardia mechanism. Satisfactory long-term arrhythmia control was achieved with flecainide.

Adult↗