Functional coupling of parietal α rhythms is enhanced in athletes before visuomotor performance: a coherence electroencephalographic study.

It has been shown that elite pistol shooters are characterized by a power increase of wide cortical electroencephalographic (EEG) alpha (about 8-12 Hz) and beta (about 14-35 Hz) rhythms during the preparation of air pistol shots, possibly related to selective attentional and "neural efficiency" processes [Del Percio C, Babiloni C, Bertollo M, Marzano N, Iacoboni M, Infarinato F, Lizio R, Stocchi M, Robazza C, Cibelli G, Comani S, Eusebi F (2009a) Hum Brain Mapp 30(11):3527-3540; Del Percio C, Babiloni C, Marzano N, Iacoboni M, Infarinato F, Vecchio F, Lizio R, Aschieri P, Fiore A, Toràn G, Gallamini M, Baratto M, Eusebi F (2009b) Brain Res Bull 79(3-4):193-200]. Here, we tested the hypothesis that such processes are associated with an enhanced functional coupling of posterior cortical regions involved in task-relevant attentional processes and visuo-motor transformations. To this aim, between-electrodes spectral coherence was computed from spatially enhanced EEG data collected during a previous study (i.e. right handed 18 elite air pistol shooters and 10 matched non-athletes; augmented 10-20 system; surface Laplacian estimation). Theta (about 4-6 Hz), low-frequency alpha (about 8-10 Hz), high-frequency alpha (about 10-12 Hz), low-frequency beta (14-22 Hz), high-frequency beta (23-35 Hz), and gamma (36-44 Hz) bands were considered. Statistical results showed that intra-hemispheric low-frequency alpha (parietal-temporal and parietal-occipital regions), high-frequency alpha (parietal-temporal and parietal-occipital regions), high-frequency beta, and gamma (parietal-temporal regions) coherence values were stable in amplitude in the elite athletes but not in the non-athletes during the preparation of pistol shots. The same applies to inter-hemispheric low-frequency alpha (parietal regions), high-frequency alpha (parietal regions), high-frequency beta and gamma coherence values. These findings suggest that under the present experimental conditions, elite athletes are characterized by the stabilization of functional coupling of preparatory EEG rhythms between "visuo-spatial" parietal area and other posterior cortical areas.

Effects of tiredness on visuo-spatial attention processes in elite karate athletes and non-athletes.

"Attentional" adaptations are fundamental effects for sport performance. We tested the hypothesis that tiredness and muscular fatigue poorly affect visuo-spatial attentional processes in elite karate athletes. To this aim, 14 elite karate athletes and 11 non-athletes were involved in an isometric contraction exercise protocol up to muscular fatigue. Blood lactate and attention measurements were taken. Posner's test probed "endogenous" (i.e., internally planned allocation of spatial attention) and "reflexive" (i.e., brisk variation of endogenous spatial attention due to unexpected external stimuli) attention. Lactate and attentional measurements were performed before (Block 1, B1) and after the fatiguing exercise (B2) and at the end of a recovery period (B3). Compared to the non-athletes, the athletes showed a better performance in the fatigue protocol, confirmed by the higher absolute lactate values in B2. The correct responses in the "valid trials" probing "endogenous" attention were 92.4% (B1), 93.9% (B2), and 95.8% (B3) in the non-athletes, and 98.5%, 96.4%, 95.5% in the elite karate athletes. The correct responses in the "invalid trials" probing "reflexive" attention were 95.4%, 89.7%, 93.2% in the non-athletes, and 96.4%, 97.3%, 98.5% in the elite karate athletes. The percentage of correct responses in the "invalid" trials significantly decreased from B1 to B2 in the non-athletes but not in the elite karate athletes. In conclusion, tiredness and muscular fatigue do not affect "reflexive" attentional processes of elite karate athletes, which is crucial to contrast attacks coming from an unexpected spatial region.

[Hyperparathyroidism from mediastinal parathyroid adenoma. Case report]. / Iperparatiroidismo da adenoma paratiroideo a localizzazione mediastinica. Caso clinico.

The authors, after reviewing parathyroid gland diseases, their location, and the modern strategies that can be used for their pre-operative detection, describe a case of primary hyperparathyroidism which recently came to their attention. The use of a combination of instrumental techniques (US, scintigraphy and SPEcT) enabled them to establish, prior to surgery, the mediastinal ectopic site of the parathyroid adenoma. Mini-invasive surgery proved to be the optimal technique to performing a targeted surgical excision that reduced the operative time and the hospitalisation.

[Hepatic hydatidosis: old and actual therapeutic strategies]. / L'idatidosi epatica: pregresse e attuali strategie terapeutiche.

The authors, reporting on their experience, confirm as the incidence of the hepatic hydatidosis and the complications related to this pathology today are very meaningful. They specify that the objectives to be pursued are: elimination of the parasite, prevention or treatment of the complications, prevention of the development of a new infestation. They dwell therefore upon the various techniques, both conservative and radical, that marked the history of the hepatic hydatidosis surgery, and they conclude affirming that the procedures of eradication of the parasite and the pericystectomy, in particular in laparotomic way, also represents the ideal treatment in consideration of the a little encouraging results of the medical therapy.

[Closed trauma of the spleen. Indications to surgical treatment]. / I traumi chiusi della milza. Indicazioni al trattamento chirurgico.

The Authors mention the historical evolution that led to consider the splenectomy as the ideal operation in patients with post-traumatic lesions of the spleen. They linger then on the actual knowledges about the physiopathology of this organ that determined a substantial change of mind to a conservative treatment, when possible. By reporting their experience of the last decade, they weigh up how every therapeutic choice must be consequent to an accurate clinical evaluation that suggests the surgical abdomen exploration in urgency or, on the contrary, the monitoring of the patient. They linger particularly on the validity of the investigation and quantization of organ lesions and of the subsequent hemoperitoneum. The Authors end affirming that an accurate diagnostic evaluation and the subsequent therapy must take place in a specialized Trauma Center that ensures intensive monitoring and, if necessary, a timely operation in these patients.

Homocysteine and electroencephalographic rhythms in Alzheimer disease: a multicentric study.

High plasma concentration of homocysteine is an independent risk factor for Alzheimer's disease (AD), due to microvascular impairment and consequent neural loss [Seshadri S, Beiser A, Selhub J, Jacques PF, Rosenberg IH, D'Agostino RB, Wilson PW, Wolf PA (2002) Plasma homocysteine as a risk factor for dementia and Alzheimer's disease. N Engl J Med 346(7):476-483]. Is high plasma homocysteine level related to slow electroencephalographic (EEG) rhythms in awake resting AD subjects, as a reflection of known relationships between cortical neural loss and these rhythms? To test this hypothesis, we enrolled 34 mild AD patients and 34 subjects with mild cognitive impairment (MCI). Enrolled people were then subdivided into four sub-groups of 17 persons: MCI and AD subjects with low homocysteine level (MCI- and AD-, homocysteine level <11 micromol/l); MCI and AD subjects with high homocysteine level (MCI+ and AD+, homocysteine level >or=11 micromol/l). Resting eyes-closed EEG data were recorded. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by low-resolution brain electromagnetic tomography (LORETA). Results showed that delta (frontal and temporal), theta (central, frontal, parietal, occipital, and temporal), alpha 1 (parietal, occipital, and temporal), and alpha 2 (parietal and occipital) sources were stronger in magnitude in AD+ than AD- group. Instead, no difference was found between MCI- and MCI+ groups. In conclusion, high plasma homocysteine level is related to unselective increment of cortical delta, theta, and alpha rhythms in mild AD, thus unveiling possible relationships among that level, microvascular concomitants of advanced neurodegenerative processes, and synchronization mechanisms generating EEG rhythms.

Controlled release by permeability alteration of cationic ammonio methacrylate copolymers using ionic interactions.

A multiparticulate drug delivery system was studied in which the drug release of a model drug theophylline could be modulated by interactions of ammonio methacrylate polymer and anions. The system consisted of a EUDRAGIT NE coated anionic core, layered with drug and further layered with EUDRAGIT RS. The effects of different anions like chloride, succinate, citrate, and acetate as well as the thickness of the polymer layers on the in vitro drug release were studied. It was seen that succinate and acetate anions had permeability enhancing effects and citrate and chloride anions had permeability retarding effects on the polymer. The results indicate that changing these variables would enable us to get a desired release profile and hence the proposed system could be a viable alternative to existing technologies for the development of a controlled drug delivery system.

Oral endotracheal intubation of rats for intratracheal instillation and aerosol drug delivery.

As reported in the literature, oral endotracheal intubation of rats is considered to be very difficult. Specialised equipment and complicated techniques have been described to perform this procedure. In our experiment we adopted a simple method, which allowed-without any complicated equipment-the insertion of a relatively wide tube into the trachea of rats, allowing drug administration.

Development of a new aerosol delivery system for systemic pulmonary delivery in anaesthetized and orotracheal intubated rats.

Over the last decade, the systemic absorption of a broad range of therapeutics after pulmonary application has been demonstrated in animals as well as in humans. The most common method used in the laboratory is the intratracheal instillation of drugs in solution. This method is, however, unsatisfactory, because of discrepancies in particle distribution, clearance, kind of injury and bioavailability between instillation and inhalative application. On the other hand, a precise determination of the amount of drug applied by aerosol, and of the aerosol volume retained within the lungs is rather difficult, and is not possible for use with small animals such as mice or rats. We describe a system which allows the delivery of aerosols directly into the animal's lungs, and calculation of the amount of drug retained in the lungs. Our system was tested in vitro and in vivo and was shown to allow precise and efficient pharmacokinetic and toxicological studies to be carried out.

Systemic delivery of cetrorelix to rats by a new aerosol delivery system.

PURPOSE: To study the pulmonary absorption and tolerability of various formulations of the decapeptide cetrorelix acetate in rats by a new aerosol delivery system (ASTA-ADS) for intratracheal application. METHODS: Using the ASTA-ADS, cetrorelix liquid formulations (aqueous solutions for ultrasonic nebulization) were firstly selected and subsequently delivered as nebulized aerosol to orotracheally cannulated rats. The pharmacologic effect (decrease of testosterone serum level) of four cetrorelix formulations was determined in rats by enzyme linked immunosorbant assay, and pharmacokinetic data were determined after measurement of cetrorelix serum level by radioimmunoassay. Histological examination of the lung was performed at the end of the experiments, and in a supplementary experiment the respiratory parameters (resistance and compliance) of rats were monitored by a validated pulmonary monitoring system during the aerosol application of the same formulations. RESULTS: After an exposure time of 5 min, the applied formulations reduced the testosterone concentration in serum to subnormal levels (< or =1 ng/ml) over a period of 24 h. Comparing the plasma concentration after intratracheal aerosolization with data of intravenous administration, the mean calculated bioavailabilities for the four formulations using the corrected dose (delivered--exhaled amount) were between 48.4 +/- 27.0% and 77.4 +/- 44.0%. The histologic examination of the lungs revealed different tolerability of the various tested formulations ranging from locally intolerable to well tolerated. The measurement of the lung function parameters did not reveal any compound or formulation related changes. CONCLUSIONS: Our studies show that cetrorelix can be effectively administered as aerosol and that intratracheal aerosolization via the ASTA-ADS provides results that are well comparable to other application routes, as demonstrated by statistical comparison of the newly obtained data with previous results from intratracheal instillation of cetrorelix solutions in rats.

Low-temperature micronization of a peptide drug in fluid propellant: case study cetrorelix.

Aim of this study was to elaborate an efficient method for the micronization of the decapeptide cetrorelix (a GnRH-antagonist), in order to obtain a microsuspension as basis for other pharmaceutical preparations, such as e.g. inhalation aerosols. A modified pearl-mill coupled with a cryostat was used for the micronization of cetrorelix in fluid propellant and operated under different conditions. The obtained cetrorelix suspensions were analyzed for particle size distribution, purity of cetrorelix, and for metal contamination through abrasion from parts of the mill. The method allowed an effective micronization of cetrorelix. The mean particle size of the initial cetrorelix lyophilizate bulk ware was reduced from 52.5 microm (Volume Mean Diameter, VMD) down to 14.9, 6.1 and 3.1 microm, respectively, respectively. The HPLC analysis of all cetrorelix suspensions after micronization did not show signs of decomposition as compared to the initial product. The elementary analysis of the suspensions performed by inductively coupled plasma mass spectrometry revealed a negligible amount of contaminants in the suspension (Zr = max. 0.6 ppm; Fe, Cr, Ni, Ba, below limit of quantification, i.e. < 0.14 ppm). The only appreciable contaminant, Aluminum (Al = 1.1 ppm), was derived from the mechanical capping of aluminum canisters prior to analysis. The Zr determination in the suspension of 0.6 ppm, is still considered to be negligible as compared to the legally tolerated limit of air contamination. By low-temperature micronization in fluid propellant, fine drug suspensions of cetrorelix for pMDIs can be directly manufactured in one-step procedure without destruction of the peptide structure and without appreciable product contamination.

Systemic delivery of the GnRH antagonist cetrorelix by intratracheal instillation in anesthetized rats.

Pulmonary absorption of the decapeptide cetrorelix acetate was studied in rats by a non-surgical intratracheal instillation method. The pharmacological effect (decrease of testosterone plasma concentration) following intratracheal (i.t.) instillation was determined in four groups of seven rats each at three different concentrations (0.5, 1.0 and 2.5 mg/kg body weight). The applied doses reduced testosterone plasma concentration to subnormal level (