Production and characterization of 111Ag radioisotope for medical use in a TRIGA Mark II nuclear research reactor.

Radio Pharmaceutical Therapy (RPT) comes forth as a promising technique to treat a wide range of tumors while ensuring low collateral damage to nearby healthy tissues. This kind of cancer therapy exploits the radiation following the decay of a specific radionuclide to deliver a lethal dose to tumor tissues. In the framework of the ISOLPHARM project of INFN, 111Ag was recently proposed as a promising core of a therapeutic radiopharmaceutical. In this paper, the production of 111Ag via neutron activation of 110Pd-enriched samples inside a TRIGA Mark II nuclear research reactor is studied. The radioisotope production is modeled using two different Monte Carlo codes (MCNPX and PHITS) and a stand-alone inventory calculation code FISPACT-II, with different cross section data libraries. The whole process is simulated starting from an MCNP6-based reactor model producing the neutron spectrum and flux in the selected irradiation facility. Moreover, a cost-effective, robust and easy-to-use spectroscopic system, based on a Lanthanum Bromo-Chloride (LBC) inorganic scintillator, is designed and characterized, with the aim of using it, in the future, for the quality control of the ISOLPHARM irradiated targets at the SPES facility of the Legnaro National Laboratories of INFN. natPd and 110Pd-enriched samples are irradiated in the reactor main irradiation facility and spectroscopically characterized using the LBC-based setup and a multiple-fit analysis procedure. Experimental results are compared with theoretical predictions of the developed models, showing that inaccuracies in the available cross section libraries prevent an accurate reproduction of the generated radioisotope activities. Nevertheless, models are normalized to our experimental data allowing for a reliable planning of the 111Ag production in a TRIGA Mark II reactor.

Radioisotopic purity and imaging properties of cyclotron-produced 99mTc using direct 100Mo(p,2n) reaction.

Evaluation of the radioisotopic purity of technetium-99m (99mTc) produced in GBq amounts by proton bombardment of enriched molibdenum-100 (100Mo) metallic targets at low proton energies (i.e. within 15-20 MeV) is conducted. This energy range was chosen since it is easily achievable by many conventional medical cyclotrons already available in the nuclear medicine departments of hospitals. The main motivation for such a study is in the framework of the research activities at the international level that have been conducted over the last few years to develop alternative production routes for the most widespread radioisotope used in medical imaging. The analysis of technetium isotopes and isomeric states (9xTc) present in the pertechnetate saline Na99mTcO4 solutions, obtained after the extraction/purification procedure, reveals radionuclidic purity levels basically in compliance with the limits recently issued by European Pharmacopoeia 9.3 (2018 Sodium pertechnetate (99mTc) injection 4801-3). Moreover, the impact of 9xTc contaminant nuclides on the final image quality is thoroughly evaluated, analyzing the emitted high-energy gamma rays and their influence on the image quality. The spatial resolution of images from cyclotron-produced 99mTc acquired with a mini-gamma camera was determined and compared with that obtained using technetium-99m solutions eluted from standard 99Mo/99mTc generators. The effect of the increased image background contribution due to Compton-scattered higher-energy gamma rays (E γ > 200 keV), which could cause image-contrast deterioration, was also studied. It is concluded that, due to the high radionuclidic purity of cyclotron-produced 99mTc using 100Mo(p,2n)99mTc reaction at a proton beam energy in the range 15.7-19.4 MeV, the resulting image properties are well comparable with those from the generator-eluted 99mTc.

Modified α,α'-trehalose and d-glucose: green monomers for the synthesis of vinyl copolymers.

Allyl saccharide/vinyl copolymers were synthesized using renewable feedstocks (α,α'-trehalose and d-glucose) to obtain 'green monomers'. Properly designed synthetic procedures were used to obtain copolymers with high purity and without protection/deprotection steps in agreement with the principles of green chemistry and industrial sustainability. The use of saccharide derivatives as monomers allowed products to be obtained that showed high affinity and compatibility for the cellulosic substrates, like paper or wood, and that were suitable for applications like adhesion or consolidation in the field of cultural heritage. All reaction products were characterized by FT-IR and NMR spectroscopies and SEC analyses, while thermal properties were evaluated by DSC analyses.

Radiation resistance of elastomeric O-rings in mixed neutron and gamma fields: Testing methodology and experimental results.

Materials and components employed in the presence of intense neutron and gamma fields are expected to absorb high dose levels that may induce deep modifications of their physical and mechanical properties, possibly causing loss of their function. A protocol for irradiating elastomeric materials in reactor mixed neutron and gamma fields and for testing the evolution of their main mechanical and physical properties with absorbed dose has been developed. Four elastomeric compounds used for vacuum O-rings, one fluoroelastomer polymer (FPM) based and three ethylene propylene diene monomer rubber (EPDM) based, presently available on the market have been selected for the test. One EPDM is rated as radiation resistant in gamma fields, while the other elastomers are general purpose products. Particular care has been devoted to dosimetry calculations, since absorbed dose in neutron fields, unlike pure gamma fields, is strongly dependent on the material composition and, in particular, on the hydrogen content. The products have been tested up to about 2 MGy absorbed dose. The FPM based elastomer, in spite of its lower dose absorption in fast neutron fields, features the largest variations of properties, with a dramatic increase in stiffness and brittleness. Out of the three EPDM based compounds, one shows large and rapid changes in the main mechanical properties, whereas the other two feature more stable behaviors. The performance of the EPDM rated as radiation resistant in pure gamma fields does not appear significantly better than that of the standard product. The predictive capability of the accelerated irradiation tests performed as well as the applicable concepts of threshold of radiation damage is discussed in view of the use of the examined products in the selective production of exotic species facility, now under construction at the Legnaro National Laboratories of the Italian Istituto Nazionale di Fisica Nucleare. It results that a careful account of dose rate effects and oxygen penetration in the material, both during test irradiations and in operating conditions, is needed to obtain reliable predictions.

Neutron flux characterisation of the Pavia TRIGA Mark II research reactor for radiobiological and microdosimetric applications.

Nowadays the Pavia TRIGA reactor is available for national and international collaboration in various research fields. The TRIGA Mark II nuclear research reactor of the Pavia University offers different in- and out-core neutron irradiation channels, each characterised by different neutron spectra. In the last two years a campaign of measurements and simulations has been performed in order to guarantee a better characterisation of these different fluxes and to meet the demands of irradiations that require precise information on these spectra in particular for radiobiological and microdosimetric studies. Experimental data on neutron fluxes have been collected analysing and measuring the gamma activity induced in thin target foils of different materials irradiated in different TRIGA experimental channels. The data on the induced gamma activities have been processed with the SAND II deconvolution code and finally compared with the spectra obtained with Monte Carlo simulations. The comparison between simulated and measured spectra showed a good agreement allowing a more precise characterisation of the neutron spectra and a validation of the adopted method.

Locating industrial VOC sources with aircraft observations.

Observation and characterization of environmental pollution, focussing on Volatile Organic Compounds (VOCs), in a high-risk industrial area, are particularly important in order to provide indications on a safe level of exposure, indicate eventual priorities and advise on policy interventions. The aim of this study is to use the Solid Phase Micro Extraction (SPME) method to measure VOCs, directly coupled with atmospheric measurements taken on a small aircraft environmental platform, to evaluate and locate the presence of VOC emission sources in the Marghera industrial area. Lab analysis of collected SPME fibres and subsequent analysis of mass spectrum and chromatograms in Scan Mode allowed the detection of a wide range of VOCs. The combination of this information during the monitoring campaign allowed a model (Gaussian Plume) to be implemented that estimates the localization of emission sources on the ground.

[The laparoscopic treatment of splenic rupture, a case report]. / Trattamento laparoscopico di rottura di milza, descrizione di un caso.

The case report refers to a splenic traumatic rupture treated conservatively by diagnostic and interventional laparoscopy. The peculiarities of the method are discussed and related to the various problems of the situation: direct observation, washing and the use of fibrin glue are the key of the success.

[Laparoscopic cholecystectomy and percutaneous echo-guided cholecystostomy. Their applications in acute cholecystitis]. / Colecistectomia laparoscopica e colecistostomia percutanea ecoguidata. Applicazioni nella colecistite acuta.

Laparoscopic cholecystectomy is nowadays proposed as elective treatment in acute cholecystitis; the advantages obtained with this method are comparable with those of laparoscopic cholecystectomy outside inflammatory complications. Moreover in emergency we have the advantage of better diagnostic definition and less surgical trauma. When acute cholecystitis affects high risk patients from the anesthesiologic view percutaneous US-assisted cholecystostomy is considered more valuable than the medical conservative treatment. Drainage of gallbladder is followed from a dramatic clinical improvement with more time for a laparoscopic cholecystectomy or for a percutaneous lithotripsy or eventually for the simple withdrawal of the catheter.

Electromagnetic shock-wave lithotripsy of gallbladder calculi. Multicentered preliminary report on experience with 276 patients.

The Lithostar Working Group reports on the first 276 patients who underwent lithotripsy of biliary calculi by means of an electromagnetic Lithotriptor (Lithostar Plus from Siemens). Some 66% (183/276) and 27% (75/276) of the patients had solitary and two or three stones, respectively while 7% (18/276) had more than three gallbladder calculi. Calcified calculi were found in 11% of the patients. On an average the patients were treated in 1.6 (range 1.4-2.15) sessions; with the exception of one user the maximal energy (setting 9) was applied. The upper limit of shock waves per session was 1500-6000 (x = 2189 +/- 1058). 17% and 48% of the patients were free from calculi after 3 and 6 months, respectively. During the follow-up period 14% of the patients complained of severe biliary pain and 1.5% suffered from pancreatitis, which was controlled by conservative treatment. In three out of five patients with a transitory cholestatic jaundice endoscopic papillotomy was necessary. Four patients underwent an elective cholecystectomy. Considering the selection of the patients, the results obtained are comparable with those found in other studies.

Experimental study on the action of diltiazem on detrusor muscle and clinical evaluation in patients with detrusor hyperactivity.

Diltiazem added to the medium before administration of the agonist, caused a concentration-dependent antagonism of potassium chloride-induced contractions in strips of rat detrusor and human detrusor. When added at the time of peak potassium chloride-induced increase in muscle tone, the drug lowered the tone gradually and concentration-dependently. Diltiazem also depressed carbachol-induced contractions. In patients with disturbances of micturition due to detrusor hyperactivity, oral diltiazem (Angizem) treatment for 10 days significantly increased bladder capacity, lowered bladder pressure and maximum detrusor pressure and raised the threshold of the second sensation of micturition. In addition, diltiazem significantly reduced frequency of diurnal and nocturnal micturition and number of episodes of incontinence. Diltiazem appears to be an effective detrusor muscle relaxant and may be useful for the treatment of disturbances of micturition due to detrusor hyperactivity.

Digital angiography of erectile failure.

Digital angiography of pudendal and penile arteries was performed in 44 consecutive patients with erectile failure of suspected vascular origin. Intra-arterial injection of contrast medium via selective catheterisation of the hypogastric arteries was used in six cases. In 39 patients, one of whom had already had arterial catheterisation, contrast medium was administered by the intravenous route, using a single, large volume, high speed bolus. In 12/44 cases (27%), digital angiography showed a normal vascular picture at the pudendal and penile level but the remaining 32 patients (73%) had steno-occlusive lesions of different degrees of severity. The pictures obtained after administration of intravenous contrast were diagnostically as good as the studies with selective arterial catheterisation. In addition, the intravenous route allowed the simultaneous representation of the arterial network on both sides and was quicker and less invasive. In 31/44 patients (79%), functional determinations of nocturnal penile tumescence and of penile blood flow with Doppler ultrasonography were performed for comparison. Nocturnal penile tumescence results correlated well with the angiographic picture. Penile blood flow measurements with the Doppler technique were less sensitive than digital angiography.

Ano-rectal manometry as an evaluating test for impaired ano-rectal function in diabetes mellitus.

Diarrhea and/or rectal incontinence may represent a sign of autonomic neuropathy in diabetes. The present investigation was performed to study ano-rectal function and reactivity to appropriate stimuli in 20 diabetic patients with or without autonomic neuropathy (14 insulin-dependent diabetics; 6 non-insulin-dependent diabetics; mean age 39.2 years; mean duration of diabetes 12.6). Twenty-five healthy subjects (mean age 43.5 years) were studied as controls. All subjects underwent ano-rectal manometry by means of special open-ended-tip catheters connected with a 6-channel polygraph. A rectal latex balloon was inflated with 30 or 60 ml air to induce a stimulus which, under normal conditions, is apt to relax the internal sphincter and to contract the external one (ano-rectal inhibitory reflex). Eleven diabetics had symptoms and signs of autonomic neuropathy: 8 of these (73%) showed marked abnormalities of ano-rectal function (i.e. no response even to maximum stimulus or contraction of both sphincters). All non-neuropathic patients showed a normal pattern of ano-rectal manometry. A relationship between abnormal response to rectal stimulation and the presence of autonomic neuropathy involving the pelvic parasympathetic section or regional intramural plexuses may be suspected and demonstrated in diabetic neuropathic patients.

[Digital angiography of the pudendal arteries in erectile impotence]. / L'angiografia digitale delle arterie pudende nello studio della impotenza erettile.

Digital angiography of pudendal and penile arteries was performed on 32 consecutive patients with erectile failure of suspected vascular origin. Intra-arterial injection of contrast medium via selective catheterization of the hypogastric arteries was used in 6 cases. In 27 cases, one of which already submitted to arterial catheterism, the intravenous route was employed for contrast administration, using a single, large volume, high speed bolus. In one case, digital angiography was diagnostically unreliable due to patient's motion and to blurring artifacts. Among the remaining cases, 9/31 (29%) showed a normal angiographic picture, while 22/31 (71%) possessed stenotic-obstructive lesions of different severity. The pictures obtained after intravenous contrast administration were diagnostically equivalent to those obtained with arterial catheterism: in addition, intravenous route allowed the simultaneous representation of the arterial network of both sides and the overall examination resulted less invasive and quicker. In 22/32 patients (69%), functional determinations of erectile capability and of penile blood flow were performed for comparison. Nocturnal penile tumescence (12 cases diagnostically useful) was well correlated with the angiographic picture. Penile blood flow measurements with the Doppler technique (21 cases) seemed on the contrary to be less sensitive than digital angiography.

[Comparative observations on the course of different types of necrosis]. / Osservazioni comparative sulla evoluzione di differenti tipi di necrosi.

Histological comparison between cryonecrosis and thermonecrosis has shown that cryonecrosis in generally better delimited and surrounded by a layer of finer and more regular granulation tissue than thermonecrosis. Moreover, the course of the cold lesion is faster and is less open to phenomena of suppurative septic and oedematous phenomena.

[Cryotherapy of hemorrhoids. Analysis of 40 cases]. / Crioterapia emorroidaria. Analisi di 40 casi.

An appraisal is made of the results of cryotherapy in 40 carefully selected cases of haemorrhoids. It is shown that the method is effective if practised in accordance with the correct technique and where specifically indicated. The incidence of possible complications and recurrences is also discussed. Points in favour of the method include its greater tolerability, the possibility of using it in out-patient management, and the fact that it permits an earlier return to work. Attention must be paid to the narrowness of its indications and the anorectal diseases that may often be present.