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1.
Rev Sci Instrum ; 91(2): 023510, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32113382

RESUMO

The requirements of ITER neutral beam injectors (1 MeV, 40 A negative deuterium ion current for 1 h) have never been simultaneously attained; therefore, a dedicated Neutral Beam Test Facility (NBTF) was set up at Consorzio RFX (Padova, Italy). The NBTF includes two experiments: SPIDER (Source for the Production of Ions of Deuterium Extracted from Rf plasma), the full-scale prototype of the source of ITER injectors, with a 100 keV accelerator, to investigate and optimize the properties of the ion source; and MITICA, the full-scale prototype of the entire injector, devoted to the issues related to the accelerator, including voltage holding at low gas pressure. The present paper gives an account of the status of the procurements, of the timeline, and of the voltage holding tests and experiments for MITICA. As for SPIDER, the first year of operation is described, regarding the solution of some issues connected with the radiofrequency power, the source operation, and the characterization of the first negative ion beam.

2.
Rev Sci Instrum ; 87(2): 02B320, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932048

RESUMO

Neutral Beam Injectors (NBIs), which need to be strongly optimized in the perspective of DEMO reactor, request a thorough understanding of the negative ion source used and of the multi-beamlet optics. A relatively compact radio frequency (rf) ion source, named NIO1 (Negative Ion Optimization 1), with 9 beam apertures for a total H(-) current of 130 mA, 60 kV acceleration voltage, was installed at Consorzio RFX, including a high voltage deck and an X-ray shield, to provide a test bench for source optimizations for activities in support to the ITER NBI test facility. NIO1 status and plasma experiments both with air and with hydrogen as filling gas are described. Transition from a weak plasma to an inductively coupled plasma is clearly evident for the former gas and may be triggered by rising the rf power (over 0.5 kW) at low pressure (equal or below 2 Pa). Transition in hydrogen plasma requires more rf power (over 1.5 kW).

3.
Neuroscience ; 89(4): 1209-17, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10362308

RESUMO

We investigated whether D1 dopaminergic receptors modulate in vivo acetylcholine output in the shell and core areas of rat nucleus accumbens using the microdialysis technique. Subcutaneous injection (1, 2 and 3 mg/kg) of the D1 agonist SKF 82958 enhanced acetylcholine output in both areas of the nucleus accumbens while the selective D1 antagonist SCH 39166 (0.15 and 0.30 mg/kg, s.c.) lowered it. Both SKF 82958 and SCH 39166 were more effective in the shell than in the core region. The increase in acetylcholine release induced by SKF 82958 in the shell was tetrodotoxin-sensitive. The dopamine release inducer d-amphetamine (1 and 2mg/kg, s.c.) and the dopamine uptake inhibitor cocaine (10 and 20 mg/kg, i.p.) dose-dependently raised acetylcholine release in the shell and core areas. The dopaminergic stimulants, like the direct-acting D1 compounds, were more effective in the shell than in the core compartment of the nucleus accumbens. The acetylcholine increases in the shell induced by d-amphetamine (2 mg/kg), cocaine (20 mg/kg) and SKF 82958 (3 mg/kg) were antagonized by the D1 antagonists SCH 39166 (5 microM) and SCH 23390 (10 microM), applied locally by reverse dialysis. The results suggest that dopamine acting at the D1 receptors exerts a tonic stimulatory control over the cholinergic function of the shell and core compartments of the nucleus accumbens with the shell being more strongly influenced.


Assuntos
Acetilcolina/fisiologia , Benzazepinas/farmacologia , Agonistas de Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , Núcleo Accumbens/fisiologia , Receptores de Dopamina D1/fisiologia , Transmissão Sináptica/fisiologia , Animais , Cocaína/farmacologia , Dextroanfetamina/farmacologia , Feminino , Microdiálise , Núcleo Accumbens/efeitos dos fármacos , Ratos , Receptores de Dopamina D1/agonistas , Receptores de Dopamina D1/antagonistas & inibidores , Transmissão Sináptica/efeitos dos fármacos , Tetrodotoxina/farmacologia
4.
Invest Ophthalmol Vis Sci ; 18(3): 320-4, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-422336

RESUMO

Monoamine oxidase (MAO, E.C. 1.4.3.4) activity was determined by spectrophotofluorimetric assay of the reaction product of the artificial substrate kynuramine in platelets from venous blood samples from 50 outpatients with glaucomas and 47 sex- and age-matched controls. No significant differences were found between MAO activity in control subjects and that in subjects with glaucomas grouped according to diagnostic subcategories. Irrespective of ocular disease, women had significantly higher enzyme activity than men. Age-related changes in platelet MAO were inconsistent.


Assuntos
Plaquetas/enzimologia , Glaucoma/enzimologia , Monoaminoxidase/análise , Adulto , Fatores Etários , Idoso , Oftalmopatias/enzimologia , Feminino , Glaucoma/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Espectrometria de Fluorescência
5.
Br J Pharmacol ; 62(1): 31-8, 1978 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-620097

RESUMO

1 Control experiments were carried out by homogenizing rat brain at 0 degrees C with sucrose containing various concentrations of [3H]-etorphine. Subcellular fractionation of this homogenate showed that the distribution of the labelled drug amongst the primary fractions was dependent on the concentration of etorphine in the homogenate. 2 Rats were injected intravenously with 0.2 and 20 microgram/kg of [3H]-etorphine. The brains were homogenized and fractionated in sucrose containing 4.2 x 10(-5) M unlabelled etorphine in order to control redistribution artifacts. Different distribution profiles in the subcellular fractions were observed at these two dose levels. 3 Concurrent administration of either cyprenorphine or naloxone with intravenous etorphine, caused a shift of the labelled drug from the P3 fraction to the supernatant fraction. 4 The subcellular distribution of intravenously administered [3H]-etorphine was also studied by homogenizing brains in etorphine-free sucrose, and sucrose containing either levorphanol or dextrorphan. From these experiments it was concluded that the P3 microsomal fraction is a major site to which in vivo etorphine is stereospecifically bound in the rat brain.


Assuntos
Encéfalo/metabolismo , Etorfina/metabolismo , Morfinanos/metabolismo , Frações Subcelulares/metabolismo , Animais , Encéfalo/ultraestrutura , Etorfina/administração & dosagem , Técnicas In Vitro , Injeções Intravenosas , Masculino , Ratos , Estereoisomerismo
6.
Eur J Pharmacol ; 32(1): 39-44, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-1149824

RESUMO

Electrolytic lesions were produced in three separate parts of the raphe mesencephalic area: the nucleus raphe medianus, the nucleus raphe dorsalis and an area between these two nuclei. Seven days after the surgery, the animals were tested for morphine analgesia using the tail compression method and then sacrificed for the estimation of brain serotonin. It was found that the analgesic effect of morphine was significantly reduced in the rats lesioned in the nucleus raphe medianus but not in the animals lesioned either in the nucleus raphe dorsalis or in the 'intermediate raphe area'. Since a decrease of forebrain serotonin was observed in each experimental group, the reduction of morphine analgesia does not involve a simple direct correlation with a decrease of serotonin in the forebrain. The results are discussed in view of the possibility that the reduction of morphine analgesia after lesions of the nucleus raphe medianus is due to a disruption of a specific brain serotonergic system.


Assuntos
Mesencéfalo/fisiologia , Morfina/farmacologia , Fenômenos Fisiológicos do Sistema Nervoso , Vias Neurais/fisiologia , Analgesia , Animais , Encéfalo/metabolismo , Feminino , Ratos , Serotonina/metabolismo
7.
Toxicol Lett ; 5(6): 417-21, 1980 May.
Artigo em Inglês | MEDLINE | ID: mdl-7394839

RESUMO

(a) A kinetic study of plasma glutamic acid (GA) was made after monosodium glutamate (MSG) administration to human volunteers. MSG was given at doses of 30,60 and 120 mg/kg in a bouillon and of 60 mg/kg in tomato juice. In another experiment a normal meal was consumed without added MSG. (2) Plasma area under the curve (AUC) was found to be lower in females than in males. (3) Plasma AUC was lower when MSG was taken in tomato juice than when consumed in bouillon. (4) Consumption of the normal meal did not result in any significant increase in plasma GA.


Assuntos
Glutamatos/metabolismo , Glutamato de Sódio/metabolismo , Adulto , Feminino , Alimentos , Glutamatos/sangue , Humanos , Cinética , Masculino
8.
Comput Methods Programs Biomed ; 22(2): 209-18, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3635460

RESUMO

A computer program for a microcomputer (HP 86) is presented to discriminate between different models and to design new experiments for model discrimination. By a non-linear fitting algorithm a set of experimental data is fitted with different models suggested by the user. The parameters characterizing each model are estimated by minimizing the sum of squared residuals; different criteria are used to test the choice between two or more models at different levels of probability and the smallest number of additional experiments required for discrimination is computed. If discrimination is not achieved a direct search method is used to find the local maxima of the divergence (or information for discrimination) over a user-chosen domain of independent variables (x R'''). The x value corresponding to the absolute maximum of the divergence is the best choice to run a new experiment for discrimination.


Assuntos
Biometria , Computadores , Modelos Teóricos , Software , Microcomputadores
9.
Ital Heart J ; 1(11): 739-48, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11110516

RESUMO

BACKGROUND: Coronary stent has become an accepted treatment modality for selected indications. However, the literature shows diverse results when indications for coronary stenting are different from those tested in large randomized trials. The purpose of this study was to determine immediate and follow-up clinical and angiographic results in patients treated with coronary stenting for indications not specifically tested in large randomized trials. METHODS: Coronary stents were implanted in a total of 2060 lesions (1757 patients) in seven groups with expanded indications: left main coronary lesions, calcified lesions, small vessels (< 3 mm in size), small vessels with diffuse disease, large vessels with diffuse disease, and bifurcation lesions treated with stents in both branches or with one stent implanted only in the major branch. Stents were implanted using high balloon pressure for final inflation and in most cases with intravascular ultrasound. Clinical follow-up was achieved in 96% of patients at a mean time of 12+/-7 months. RESULTS: Primary success (range 89-96%) and acute complications (range 5.7-13%) were comparable in all groups. At follow-up, the mortality rate was highest in the group of left main stenting (12.5%) but 20% of these patients had coronary stenting on non-elective basis. The restenosis rates ranged between 16-43%. The restenosis rate was highest in the group of bifurcation lesions with stent implantation in both vessels leading to a major adverse cardiac event (MACE) rate of 62% in this group. However, the survival rate at 1 and 2 years in the overall study group was 97 and 96%, and the event free survival was 76 and 74%, respectively. The procedure-related predictors of MACE were: final intravascular ultrasound result, use of stents with non-slotted tube morphology, final stent percent stenosis, and vessel size. CONCLUSIONS: Coronary stenting beyond standard indications is feasible, with acceptable primary success and complication rates. However, the overall MACE rates were relatively high (34-62%), in particular for the indication of bifurcation lesions with stents implanted in both vessels.


Assuntos
Angioplastia Coronária com Balão , Doença das Coronárias/terapia , Stents , Fatores Etários , Idoso , Análise de Variância , Angiografia Coronária , Ponte de Artéria Coronária , Doença das Coronárias/mortalidade , Doença das Coronárias/cirurgia , Interpretação Estatística de Dados , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Fatores de Tempo
10.
Ann Ist Super Sanita ; 28(4): 533-46, 1992.
Artigo em Italiano | MEDLINE | ID: mdl-1303048

RESUMO

The results of five years activity of the National Register of children with Congenital Hypothyroidism (NRCH) have been evaluated. NRCH was established in Italy in 1987, as a pilot project of Health Ministry. All Italian Centers in charge of the screening, treatment and follow-up of CH are involved in the program. The results have provided further epidemiological informations about CH in Italy and have evidenced some aspects in the screening organization which had to be improved. Discussion of Register data in annual meetings has recently allowed to obtain an improvement especially for the beginning of treatment and the used dose of therapy.


Assuntos
Hipotireoidismo Congênito , Triagem Neonatal , Sistema de Registros , Humanos , Hipotireoidismo/complicações , Hipotireoidismo/tratamento farmacológico , Hipotireoidismo/epidemiologia , Recém-Nascido , Itália
11.
Rev Sci Instrum ; 85(2): 02A704, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593438

RESUMO

Neutral Beam Injectors (NBI), which need to be strongly optimized in the perspective of DEMO reactor, request a thorough understanding of the negative ion source used and of the multi-beamlet optics. A relatively compact RF ion source, named NIO1 (Negative Ion Optimization 1), with 9 beam apertures for a total H(-) current of 130 mA, 60 kV acceleration voltage, is being installed at Padua, in Consorzio RFX, to provide a test bench for source optimizations in the framework of the accompanying activities in support to the ITER NBI test facility. NIO1 construction and status of the overall installation, including a high voltage deck and an optical cavity ring down spectrometer are here summarized and reported. Plasma and low voltage beam operations are discussed. Development of a sampling beam calorimeter (with small sampling holes, and a segmented cooling circuit) is also discussed.

12.
Rev Sci Instrum ; 83(2): 02A707, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22380216

RESUMO

A 60 kV ion source (9 beamlets of 15 mA each of H(-)) and plasma generators are being developed at Consorzio RFX and INFN-LNL, for their versatility in experimental campaigns and for training. Unlike most experimental sources, the design aimed at continuous operation. Magnetic configuration can achieve a minimum ∣B∣ trap, smoothly merged with the extraction filter. Modular design allows for quick substitution and upgrading of parts such as the extraction and postacceleration grids or the electrodes in contact with plasma. Experiments with a radio frequency plasma generator and Faraday cage inside the plasma are also described.

13.
Rev Sci Instrum ; 81(2): 02A713, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20192383

RESUMO

Negative ion sources are a key component of the neutral beam injector to be installed in the International Thermonuclear Experimental Reactor. At present research and development activities address several important issues related to beam extraction, optics, and optimization. Together with the design of real size devices and the accumulation of atomic cross section databases, a relatively small negative ion source [130 mA of H(-) at 60 kV, named Negative Ion Optimization phase 1 (NIO1)] is under construction at Consorzio RFX to contribute to benchmark numerical simulation tools and to test components, such as emittance scanners, beam dumps, and cesium ovens. NIO1 design, magnet configuration, and rf coupling simulations are described.

14.
Comput Programs Biomed ; 15(2): 111-6, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6897213

RESUMO

Non-parametric statistical methods have been the subject of renewed interest. They are particularly useful in the behavioral sciences as they can be applied to a large class of distributions, and because the investigator is not forced into making any erroneous assumptions about a Gaussian distribution for the parent population or about equal variances in the contrasted groups. The randomization test is the most powerful non-parametric test [1] but it is rarely used because it calls for a prohibitive amount of computation. However, two tools now available make it more feasible: simulation and high-speed computer calculations. This test's importance lies in the extremely simple logic by which it is set up. The program described here is written in BASIC language for a microcomputer and carries out an approximate randomization test using a simulated distribution instead of the entire distribution. This version is slightly less powerful, a small price to pay for reducing the enormous calculation capacity otherwise required.


Assuntos
Computadores , Distribuição Aleatória , Projetos de Pesquisa , Software , Estatística como Assunto
15.
Comput Programs Biomed ; 14(1): 7-20, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7067421

RESUMO

The main routine statistical analyses can be carried out from start to finish on a minicomputer with basic language capability and greater than or equal to 32000 bytes of random access memory. However, no statistical software packs for minicomputers are ever complete enough for exhaustive analysis of most problems. Taking account of the requirements of statistical models, this paper gives an outline of how to set up a program. Examples are given from the package of statistical programs developed at this institute. The advantages and disadvantages of making these analyses on minicomputers are discussed, in comparison with the use of statistical programs requiring large computers.


Assuntos
Biometria , Computadores , Minicomputadores
16.
Toxicol Appl Pharmacol ; 68(3): 434-41, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6857677

RESUMO

Mouse strains with different susceptibility to aryl hydrocarbon hydroxylase (AHH) induction and with different levels and/or affinity for a specific cytosolic binding protein ("receptor") were used to investigate the immunosuppressive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Humoral antibody production was strongly inhibited in C57Bl/6 and C3H/HeN mice (more susceptible strains) with very low, single doses of TCDD (1.2 micrograms/kg), while other strains (DBA/2 and AKR) required higher doses (at least 6 micrograms/kg) to be partially suppressed. Longer exposure (8 weeks) did not increase the sensitivity of DBA/2 mice. A good correlation between the degree of enzyme inducibility and immunosuppression was observed in studies with B6D2F1 mice and backcrosses. Similar results were obtained with 2,3,7,8-tetrachlorodibenzofuran (TCDF), the most powerful competitor for TCDD "receptor" in vitro and in vivo. TCDD immunotoxic effects appeared to be associated with the presence of a specific cytosolic binding protein which mediates AHH induction.


Assuntos
Formação de Anticorpos/efeitos dos fármacos , Hidrocarboneto de Aril Hidroxilases/biossíntese , Dioxinas/toxicidade , Dibenzodioxinas Policloradas/toxicidade , Animais , Cruzamentos Genéticos , Indução Enzimática/efeitos dos fármacos , Terapia de Imunossupressão , Masculino , Camundongos , Camundongos Endogâmicos , Especificidade da Espécie
17.
Oncology ; 39(3): 173-8, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6952138

RESUMO

Data on anorexia and cachexia induced by Walker carcinoma 256 in Sprague-Dawley rats were analyzed in order to standardize an experimental model using a statistical (nondeterministical) procedure for assessing the efficacy of potential orexigenic agents. This model was characterized by a mean survival time of 14 +/- 1 days and by food intake and body weight loss starting from day 6 after tumor implantation. The complex course of cachexia was characterized by reduction in the weight of gastrocnemius muscle and epididymal adipose tissue, taken as representative sites of loss of proteins and lipids.


Assuntos
Anorexia/etiologia , Caquexia/etiologia , Carcinoma 256 de Walker/complicações , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Tecido Adiposo/anatomia & histologia , Animais , Peso Corporal , Modelos Animais de Doenças , Ingestão de Alimentos , Humanos , Proteínas Musculares/análise , Músculos/anatomia & histologia , Tamanho do Órgão , Ratos , Ratos Endogâmicos
18.
Epilepsia ; 16(5): 759-64, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1222752

RESUMO

Two preparations of carbamazepine, as tablets and in syrup, were given for 8 weeks to 20 patients with epilepsy in a randomized crossover study. Weekly plasma levels were 3-21 mg/1 on dosages of 5-24 mg/kg/day. There was no difference in absorption or steady-state level between the two preparations. Carbamazepine 10, 11-oxide was constantly present when the level of carbamazepine was over 5 mg/l, and tended to be lower with the syrup.


Assuntos
Carbamazepina/administração & dosagem , Epilepsia/tratamento farmacológico , Administração Oral , Adulto , Disponibilidade Biológica , Carbamazepina/efeitos adversos , Carbamazepina/sangue , Criança , Humanos , Masculino , Suspensões , Comprimidos , Fatores de Tempo
19.
Neuropsychobiology ; 1(5): 267-76, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1232561

RESUMO

The GH response to insulin hypoglycemia (insulin 0.1 IU/kg i.v.) was studied under basal conditions and during a course of haloperidol therapy in 19 chronic schizophrenics, 15 hebephrenics and four paranoids (ten men and nine women, age 16--53 years). Haloperidol was given for 30 days, at a daily dose of 6 mg i.m., and the GH response to insulin-induced hypoglycemia was tested twice, before, and 10, 20, 30 days following the initiation of the treatment. The psychopathological features were controlled daily by two psychiatrists and by the ward staff and by the use of a Wittenborn rating scale, rated at the same intervals as the hormonal assays. From the results obtained it appears that in schizophrenic patients, GH secretion and response to insulin stimulus are extremely variable and are unaffected by haloperidol treatment. On the basis of the results obtained, the neurotransmitter-neurohormone regulation of GH secretion in schizophrenics is discussed.


Assuntos
Hormônio do Crescimento/metabolismo , Esquizofrenia/fisiopatologia , Adolescente , Adulto , Doença Crônica , Feminino , Haloperidol/uso terapêutico , Humanos , Insulina/farmacologia , Masculino , Pessoa de Meia-Idade , Esquizofrenia Hebefrênica/tratamento farmacológico , Esquizofrenia Hebefrênica/metabolismo , Esquizofrenia Paranoide/tratamento farmacológico , Esquizofrenia Paranoide/metabolismo
20.
Gastroenterology ; 85(4): 852-8, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6193028

RESUMO

Overnight-fasted male rats given a single dose of tritium-labeled morphine either intraperitoneally or intravenously were fed a charcoal test meal by stomach tube. The drug remaining in tissues was assayed by liquid scintillation counting of thin-layer chromatograms from homogenates, and gastrointestinal transit was tested by measuring the portion of the small intestine traversed by charcoal in 5 min. Morphine, 0.15 mg/kg, given intraperitoneally either 10 min or 30 min before testing substantially reduced gastrointestinal transit (to 23% and 55% of drug-free controls, respectively), and produced maximum drug levels 5 min after administration in small intestine longitudinal muscle with attached myenteric plexus (500 +/- 42 ng/g, mean +/- SE, n = 4). Intact small intestine, plasma, and brain, respectively, contained decreasing drug concentrations that, in the latter, never exceeded 2%-3% of that in longitudinal muscle. Rats receiving 0.15 mg/kg morphine intravenously presented only minor and short-lived inhibition of gastrointestinal transit that was significantly below (approximately 35%) that of drug-free controls at 10 min, but not 30 min, after drug administration. Morphine levels in the brain and plasma of these rats were up to five times higher, and in the intact small intestine longitudinal muscle were up to 20 times lower than in intraperitoneally treated rats. Morphine concentration in the tissues assayed was plotted against the effect on gastrointestinal transit at the same interval for individual rats regardless of dose, administration route, and observation time: data analysis, in small intestine longitudinal muscle, but not in the brain or plasma, indicated a highly significant correlation and fitting of computer-generated curves described by a currently accepted equation according to the receptor occupation theory of drug response. In view of these findings, and of the complete prevention by the "peripherally selective" narcotic antagonist N-methyl naloxone of gastrointestinal transit inhibition after an intravenous analgesic dose of morphine (1 mg/kg), the investigated animal model is consistent with the primary role of a gut-located action site in opiate-induced constipation.


Assuntos
Motilidade Gastrointestinal/efeitos dos fármacos , Intestino Delgado/metabolismo , Morfina/farmacologia , Peristaltismo/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Hidromorfona/análogos & derivados , Hidromorfona/farmacologia , Intestino Delgado/fisiologia , Masculino , Morfina/sangue , Morfina/metabolismo , Oximorfona/farmacologia , Ratos
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