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The study aimed to evaluate safety and efficacy of shifting stimulation settings from constant-voltage (CV) to constant-current (CC) programming in patients with Parkinson's disease (PD) and chronic subthalamic nucleus deep brain stimulation (STN DBS). Twenty PD patients with chronic STN DBS set in CV programming were shifted to CC and followed for 3 months; the other stimulation settings and the medication regimen remained unchanged. Side effects, motor, non-motor, executive functions, and impedance were assessed at baseline and during follow-up. No adverse events were observed at time of shifting or during CC stimulation. Motor and non-motor measures remained unchanged at follow-up despite impedance decreased. Compared to baseline, inhibition processes improved at follow-up. The shifting strategy was well tolerated and the clinical outcome was maintained with no need to adjust stimulation settings or medications notwithstanding a decrease of impedance. Improvement of inhibition processes is a finding which needed further investigation. [ABSTRACT FROM AUTHOR]

This work relates to the electrochemical deposition of Nb from a liquid solution in which the ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([BMP][TFSA]) is used as solvent. Conductive diamond was employed as substrate, while the experiments were carried out with NbF in the presence of either NaF or LiF. Cyclic voltammetries were used to characterise the electrochemical behaviour of the system. Deposition experiments were carried out at fixed potentials, corresponding to the voltammetric peaks of the cathodic scans. The surfaces were characterised by scanning electron microscope-energy dispersive X-ray (SEM-EDX) analysis and the results used in combination with the voltammetries to establish a possible mechanism for the Nb electrodeposition process. The electroreduction of Nb(V) to Nb(0) was found to proceed through different steps, involving the formation of the Nb(II) carbide and other nonstoichiometric carbide phases. The effect of Na and Li ions on the electrochemical process was studied: although three voltammetric peaks were detected in both cases, an appreciable depolarisation of the cathodic reactions was observed in the presence of Li ions. XRD analysis confirmed that a coating of metallic Nb was obtained at −1.5 V and 125 °C in the presence of LiF. [ABSTRACT FROM AUTHOR]

The results of an experimental study on the photo electrochemical behavior of nanotubular TiO structures are presented in this work. TiO samples were prepared by electrochemical anodization of Ti foils and submitted to thermal annealing. The influence of the current transient during the anodization, and of the annealing temperature on the photochemical response of the samples at different wavelengths was studied. Different behavior of the samples was observed, which may be attributed to the distributions of defects and to their different sensitivity to the temperature. The analysis of the performance of the samples in absence or in the presence of glycerol, used as hole scavenger, provided more information on the photo-catalytic properties of these structures. [ABSTRACT FROM AUTHOR]

In this work a undivided parallel plate cell equipped with boron doped diamond (BDD) anode was tested as electrochemical reactor for disinfection of water. Two configurations were adopted: a single pass configuration (SPC) and a recirculated configuration (RC) in which also a reservoir was inserted in the hydraulic circuit. In both the experimental configurations the system worked in continuous mode with a flow rate ranging from 0.05 to 0.42 dm min; in the RC the recirculating flow rate ranged from 0.45 to 6 dm min. Thermostated (25 °C) galvanostatic electrolyses were carried out with aqueous solutions containing 100 mg dm of chloride ions: values of current density from 2.5 to 5.0 mA cm were used. Steady state data revealed that active chlorine and chlorate ions were the main oxidation products. Particular attention was paid to the hydrodynamics both for SPC and RC: pulse-response curves were experimentally obtained with an inert tracer, and the behaviour of the system was interpreted by models based on a combination of ideal flow reactors, bypass flow elements, and dead zones. The hydrodynamic models were utilized to predict the outlet concentration of the electrolysis products. A good agreement between model predicted and experimental data was obtained for a wide range of experimental conditions. Preliminary disinfection tests were then performed using Escherichia coli as model microorganism. Results were discussed in terms of both disinfection efficiency and by-products formation. [ABSTRACT FROM AUTHOR]

In this work the products of the oxidation at BDD anode of chloride ions in aqueous solutions were identified during galvanostatic electrolyses performed in a filter-press reactor operating both in batch and continuous mode. A set of experiments were preformed in order to study the effect of operating conditions (current density, residence time, hydrodynamics and chloride concentration) on distribution and concentration of electrolysis by-products. As a comparison experiments were also performed using a commercial DSA anode. A simple mathematical model was formulated, and the model predictions agree with the experimental data in a wide range of experimental conditions. The results of this work showed that at low chloride concentrations electrolysis with BDD anode produce a mixture of powerful oxidant: low current density, high mass transfer conditions and low residence time were found as optimal conditions to maximize the concentration of oxidants and minimize the concentration of chlorates. The proposed reaction mechanism may also justify the controversial effect of chloride ions in wastewater treatments: the electrolysis carried out with BDD anodes and electrolyte containing chloride concentration higher 1 g/L could meet the target of the process only if the active chlorine is effective in oxidation of the pollutant that must be removed. [ABSTRACT FROM AUTHOR]

The results of an experimental study on electrochemical disinfection of water are presented. Attention was paid to the behaviour of chlorine compounds during electrolysis of water containing chlorides, with particular regard to the selectivity of the process towards the production of oxidising agents. Two reactor configurations were tested: a stirred tank cell and a filter press cell inserted in a hydraulic circuit. Both cells were equipped with boron doped diamond (BDD) anodes. Experiments were performed in batch and continuous mode. The effect of such operating parameters, current density, stirring rate or recirculating flow rate, on the behaviour of the process was investigated. The results at BDD anodes show that low current densities and perfect mixing of the system should be adopted in order to obtain high values of the concentration of oxidising agents avoiding the formation of such undesired by-products as chlorite, chlorate and perchlorate ions. Runs were also performed in which BDD was substituted by a commercial (Ti/RuO2) DSA anode and the results obtained with the two materials are compared. [ABSTRACT FROM AUTHOR]

Content of fluoride compounds in some typical Ethiopian water sources was analysed and several commonly available soils were characterized for their adsorption properties regarding the water defluoridation. Various soils were collected in different Ethiopian sites and the samples were analysed by X-ray diffractometry for their mineralogical composition. Batch experimental runs at room temperature were performed to evaluate the adsorption capacity of each soil sample as well as to deduce the adsorption isotherms of fluoride ions with respect to the examined soils. The best soil was identified in terms of adsorption capacity and considered for the design of two different adsorption apparatuses. Considering the water consumption of a small rural community, the capacity of the adsorption unit was selected to assure a reduction of the fluoride concentration in drinking water to the limits recommended by the World Health Organization and to allow a suitable working time of the adsorption unit before the replacement of adsorbent would be necessary. [ABSTRACT FROM AUTHOR]

Sensorimotor integration is an essential feature of the central nervous system that contributes to the accurate performance of motor tasks. Some patients with multiple system atrophy with parkinsonian features (MSAp) exhibit clinical signs compatible with an abnormal central nervous system excitability to somatosen- sory inputs, such as action myoclonus or enhanced cutaneo-muscular reflexes. To investigate further the site where such dysfunction in sensorimotor integration takes place, we examined the inhibitory effects of a cutaneous afferent volley at two different levels of the motor system in 10 MSAp patients and in 10 agematched healthy volunteers. Electrical digital nerve stimuli were given as the conditioning stimulus for the motor evoked potentials (MEP) elicited by transcranial magnetic stimulation in hand muscles, and for the blink reflex responses obtained in the orbicularis oculi muscles by supraorbital nerve stimulation. Intervals for the conditioning were 20 to 50ms for the MEP and 90 to 110ms for the blink reflex. The MEP was significantly inhibited in test trials in healthy volunteers, reaching a mean of 32% of the baseline values at the ISI of 35 ms. Significant inhibition occurred also in the blink reflex, in which the R2 response was a mean of 12% of baseline values at the ISI of 100 ms. The inhibitory effects were abnormally reduced in 8 patients on the MEP, and in 7 patients on the blink reflex. There were significant group differences between patients and control subjects in the size of the conditioned MEP and blink reflex. These results suggest that sensorimotor integration is abnormal in patients with MSAp in at least two central nervous system sites: the sensorimotor cortex, and the brainstem reticular formation. [ABSTRACT FROM AUTHOR]

This work investigates the performance of BDD electrodes during oxidation of aqueous solutions of phenol. The main reaction intermediates are identified, the effect of operating conditions on the faradic yield of the process, and the degree of mineralization achievable under different experimental conditions are evaluated. Due to the crucial role of mass transfer in the process, an impinging jet cell is used for the experiments. The results indicate that if a minimum value of current density is imposed, suitable initial conditions can be set at which the removal of the reactant is always under mass transfer control and the process is carried out at a faradic yield of about unity, up to the near-complete disappearance of total organic load. High current density and high mass transfer coefficient must be used in order to carry out the process with high space-time yield. The performance of BDD is compared to that obtained at Ti/RuO2 anodes. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the frequency of extra-articular manifestations (EAMs) of rheumatoid arthritis (RA) in a series of patients from nine Italian rheumatology clinics. A total of 587 patients underwent direct questioning, complete physical evaluation, and review of medical records and laboratory data. The relationships between EAMs and the eosinophilic count, IgM rheumatoid factor (RF), and antinuclear antibodies (ANA) were studied. EAMs were present in 240/587 (40.9%) patients. The most common features were sicca syndrome (17.5%) and rheumatoid nodules (16.7%). EAMs were significantly more frequent in male patients (OR=1.68), patients with ANA positivity (OR=2.82), high anatomical class (OR=2.3), and rheumatoid factor seropositivity (OR=2.22). EAMs were more common in patients from southern Italy than in those from northern Italy ( P < 0.001). EAMs seem to be rarer in Italy than in the Anglo-Saxon populations of northern Europe and the USA. Differences in prevalence of EAMs can exist even within the same country. [ABSTRACT FROM AUTHOR]

Electrochemical oxidation of 2-chlorophenol was studied at Ti/PbO2 and Ti/SnO2 anodes. The performance of the electrodes was evaluated in terms of faradaic yield and fraction of toxic intermediates removed during the electrolysis. Results showed that, although similar average faradaic yields were obtained using Ti/PbO2 or Ti/SnO2 anodes, the latter material is preferred because of its better ability to oxidise toxic compounds. An effective electrochemical treatment (ηF≅50%) may be accomplished, in which electrolysis at Ti/SnO2 can be stopped when, in spite of a relatively high COD, only a small amount of easily biodegradable oxalic acid is present in the effluent. [ABSTRACT FROM AUTHOR]

The effect of the 'in vivo' administration of sodium valproate on t-[S]butylbicyclophosphorothionate (S-TBPS) binding measured 'ex vivo' in the rat cerebral cortex was investigated. Sodium valproate produced a decrease of S-TBPS binding. The maximal effect (−32%) was reached with the dose of 400 mg/kg i. p., 60 min after the administration of the drug. Saturation experiments revealed that the effect of sodium valproate was due to a decrease in the total number of binding sites with no changes in the affinity constant. A small dose of diazepam (0.5 mg/kg, i. p.), which per se does not modify S-TBPS binding, markedly potentiated the inhibitory effect of sodium valproate on S-TBPS binding. Moreover, the 'in vitro' addition of sodium valproate to cortical membranes failed to modify S-TBPS binding, indicating that the effect of the 'in vivo' administration of this drug is not due to its direct interaction with the chloride associated binding sites. These results strongly suggest that this drug enhances the function of GABAergic synapses at the level of the GABA-coupled chloride channel. This conclusion supports the hypothesis that an enhancement of GABAergic transmission plays a role in the molecular mechanism involved in the antiepileptic action of sodium valporate. [ABSTRACT FROM AUTHOR]

The article presents a letter to the editor about the clinical trial focused on the applicability of interferon in treating chronic inflammatory demyelinating polyneuropathy.

A letter to the editor is presented in response to the article "Spinal cord involvement during hypertensive encephalopathy: clinical and radiological findings," by Antonio Lilia, J. Moller, G. Pilia, M. G. Mascia, P. Marchi, M. Mura, and M. G. Marrosu in the January 18, 2008 issue.

Chronic delusional psychosis with hallucinations (CDHP) is commonly assumed to complicate the later stages of Parkinson's disease, as a side effect of antiparkinsonian medication. We studied 7 patients with early onset PD, who had developed psychiatric manifestations consisting in CDHP after a few years of antiparkinsonian therapy. All patients underwent a neurological, psychiatric and brain imaging (CT or MRI) evaluation. Detailed clinical history was recorded in order to reveal prior psychiatric illness and to analyse the relationship between neurological disease, cognitive impairment and psychosis. Our findings suggest that CDHP occurring in patients with early onset PD, normal or slightly impaired cognitive functions and normal CT/MRI scans is invariably the expression of a coexisting psychiatric illness which prior to onset of the neurologic disease had not been correctly diagnosed and which has been disclosed by dopaminergic therapy. [ABSTRACT FROM AUTHOR]