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1.
Rev Sci Instrum ; 81(10): 10D937, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21061483

RESUMO

The oblique electron cyclotron emission (ECE) diagnostic installed at JET allows simultaneous analysis of the ECE spectra along three lines of sight (with toroidal angles of 0°, ∼ 10°, and ∼ 20°) and two linear polarizations for each oblique line of sight. The diagnostic is capable of measuring EC emission over the band of 75­800 GHz with 5 ms time resolution and 7.5 GHz spectral resolution, and it is designed to investigate the features of ECE spectra related to electron distribution in the thermal velocity range. Instrumental accuracy was assessed using sources at different temperatures (77­900 K) and with plasma emission. ECE from high temperature plasmas and in the presence of fast ions has been compared to simulations performed with the modeling code SPECE, setting an upper limit to possible discrepancies from thermal emission.

2.
Exp Neurol ; 215(2): 388-96, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19071114

RESUMO

An altered glutamatergic input at corticostriatal synapses has been shown in experimental models of Parkinson's disease (PD). In the present work, we analyzed the membrane and synaptic responses of striatal neurons to metabotropic glutamate (mGlu) receptor activation in two different mouse models of inherited PD, linked to mutations in PINK1 or Parkin genes. Both in PINK1 and Parkin knockout ((-/-)) mice, activation of group I mGlu receptors by 3,5-DHPG caused a membrane depolarization coupled to an increase in firing frequency in striatal cholinergic interneurons that was comparable to the response observed in the respective wild-type (WT) interneurons. The sensitivity to group II and III mGlu receptors was tested on cortically-evoked excitatory postsynaptic potentials (EPSPs) recorded from medium spiny neurons (MSNs). Both LY379268 and L-AP4, agonists for group II and III, respectively, had no effect on intrinsic membrane properties, but dose-dependently reduced the amplitude of corticostriatal EPSPs. However, both in PINK1(-/-) and Parkin(-/-) mice, LY379268, but not L-AP4, exhibited a greater potency as compared to WT in depressing EPSP amplitude. Accordingly, the dose-response curve for the response to LY379268 in both knockout mice was shifted leftward. Moreover, consistent with a presynaptic site of action, both LY379268 and L-AP4 increased the paired-pulse ratio either in PINK1(-/-) and Parkin(-/-) or in WT mice. Acute pretreatment with L-dopa did not rescue the enhanced sensitivity to LY379268. Together, these results suggest that the selective increase in sensitivity of striatal group II mGlu receptors represents an adaptive change in mice in which an altered dopamine metabolism has been documented.


Assuntos
Córtex Cerebral/citologia , Corpo Estriado/citologia , Neurônios/fisiologia , Proteínas Quinases/deficiência , Receptores de Glutamato Metabotrópico/metabolismo , Sinapses/genética , Ubiquitina-Proteína Ligases/deficiência , Aminoácidos/farmacologia , Animais , Fenômenos Biofísicos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Dopaminérgicos/farmacologia , Estimulação Elétrica/métodos , Agonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/genética , Técnicas In Vitro , Levodopa/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/genética , Camundongos , Camundongos Knockout , Neurônios/citologia , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp/métodos , Propionatos/farmacologia , Sinapses/efeitos dos fármacos
3.
Neuropharmacology ; 55(4): 392-5, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18602651

RESUMO

In the recent past, evidence accumulated in favour of a central role of group I metabotropic glutamate (mGlu) receptors, mGlu1 and mGlu5, in the modulation of cell excitability both of striatal medium spiny projection neurons (MSNs) and interneuronal population. Electrophysiological and pharmacological studies have clearly shown that activation of mGlu1 and mGlu5 receptors exerts distinct actions, depending on the neuronal subtype involved. MGlu5 receptor activation mediates the potentiation of NMDA responses in MSNs, and underlies the retrograde inhibitory signaling by endocannabinoids at corticostriatal synapses. Conversely, both group I mGlu receptors are involved in long-term synaptic plasticity of MSNs. Likewise, either mGlu1 or mGlu5 receptors are engaged in shaping the excitability of large cholinergic interneurons, playing different roles in the membrane responses. Differently, although GABAergic parvalbumin-positive, fast-spiking interneurons have been shown to express both group I receptors, only mGlu1 receptor seems to mediate membrane and synaptic responses. This review provides a brief survey of the cellular and synaptic actions of group I mGlu receptors, and discusses the potential relevance of these findings in neostriatal function and motor control.


Assuntos
Corpo Estriado/metabolismo , Receptores de Glutamato Metabotrópico/fisiologia , Animais , Humanos
4.
Eur Rev Med Pharmacol Sci ; 10(1): 17-22, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16494106

RESUMO

BACKGROUND AND OBJECTIVES: Faecal calprotectin is predictive of clinical relapse in inflammatory bowel disease and ultrasound is sensitive in detecting its post-surgical recurrence. However, no data regarding the role of calprotectin in predicting post-surgical recurrence in asymptomatic Crohn's disease are available. The aim of this study was to prospectively evaluate the role of calprotectin as a predictive marker for one year post-surgical endoscopic recurrence in comparison with ultrasound in patients with asymptomatic Crohn's disease. MATERIAL AND METHODS: We consecutively enlisted 50 patients who had undergone a resection for Crohn's disease. Faecal calprotectin was analysed and ultrasound were performed at the third month, and a colonoscopy after one year. The sensitivity and specificity of these two techniques were evaluated using endoscopic findings as a golden standard. A Receiver Operator Curve (ROC) curve was plotted, in order to identify the best-cut off value for calprotectin. RESULTS: 39 out of 50 patients were evaluated by performing a colonoscopy after one year; 19 patients had an endoscopic recurrence after one year. Calprotectin sensitivity and specificity were calculated for 5 different cut-off values; the best cut-off value for calprotectin sensitivity (63%) and specificity (75%) was > 200 mg/L. The US sensitivity and specificity at the third month were 26% and 90% respectively. CONCLUSIONS: When performed three months after surgery ultrasound is more specific than calprotectin in predicting endoscopic recurrence. Faecal calprotectin at a dosage > 200 mg/L seems to have a better sensitivity than ultrasound. Values of calprotectin > 200 mg can be an indication to colonoscopy in the group of patients with negative ultrasound in order to detect early recurrence.


Assuntos
Doença de Crohn/diagnóstico por imagem , Doença de Crohn/metabolismo , Fezes/química , Íleo/diagnóstico por imagem , Complexo Antígeno L1 Leucocitário/análise , Adolescente , Adulto , Biomarcadores/análise , Colonoscopia , Feminino , Humanos , Íleo/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Recidiva , Sensibilidade e Especificidade , Ultrassonografia
5.
Neuropharmacology ; 47(8): 1198-204, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15567429

RESUMO

The effects of the acetylcholinesterase inhibitor donepezil on cell viability and proliferation events have been analysed in SH-SY5Y human neuroblastoma cells. Short- (48 h) or long-term (7 days) exposure of SH-SY5Y cells to donepezil (100 nM-10 microM) induced a concentration-dependent inhibition of cell proliferation that was not modified by muscarinic and nicotinic receptor antagonists, or mimicked by galantamine, and was not related to induction of apoptosis. By analysing the distribution profile of cell populations within the cell cycle following treatment with 10 microM donepezil, a reduction of cells in the S-G2/M phases of the cycle and a parallel increase of the G0/G1 population were observed. In addition, the expression of two cyclins of the G1/S and G2/M transitions, cyclin E and cyclin B, was significantly reduced in donepezil-treated cells. In contrast, the expression of the cell cycle inhibitor p21 rapidly (6 h) increased following exposure to the drug. Finally, donepezil increased the expression of the neuronal marker MAP-2 in selected subpopulations of SH-SY5Y cells, suggesting that the effect on cell proliferation by donepezil may correlate to a trend to neuronal differentiation.


Assuntos
Inibidores da Colinesterase/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Indanos/administração & dosagem , Neurônios/efeitos dos fármacos , Piperidinas/administração & dosagem , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Donepezila , Relação Dose-Resposta a Droga , Humanos , Neurônios/citologia , Neurônios/enzimologia
6.
Minerva Chir ; 54(9): 573-89, 1999 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-10549204

RESUMO

BACKGROUND: In the last years the real innovation in the treatment of groin hernia is represented by tension-free hernioplasty under local anaesthesia, based on the techniques of Lichtenstein and Trabucco, which use synthetic prosthesis (polypropylene) to restore the floor of inguinal tract and enable an early deambulation and return to work. METHODS: In 21 months the authors have treated, only under local anaesthesia, 100 patients, 95 men and 5 women; the age ranged from 18 to 82 years; some of them suffer from systemic pathology (7 patients with cardiovascular diseases, 1 with epilepsy, 3 with pulmonary diseases, 1 with liver cirrhosis). All patients underwent short-term antibiotic prophylaxis. No mortality was recorded. The mean follow-up was 12.5 months with only one little and low recurrence detected. RESULTS: Good results were obtained also in terms of intraoperative complication (nausea, vomiting, bradycardia, pain) and post-operative complications, (ecchymosis of scrotum and penis, edema of the scrotum, swelling of the skin suture, subcutaneous hematoma, inguinal pain, fever), not life-threatening, well tolerated and resolved spontaneously. CONCLUSIONS: The authors stress the advantages of local anaesthesia, the economic spare due, to one day hospital stay, the safety of the technique also in patients with severe general diseases (0.9-1% in USA). The authors survey the international literature confirming the great effectiveness of tension-free inguinal hernioplasty, in particular in terms of recurrences (Trabucco 0-0.025%, Amid 0.1%).


Assuntos
Anestesia Local/métodos , Hérnia Inguinal/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Polipropilenos , Cuidados Pré-Operatórios/métodos , Telas Cirúrgicas , Procedimentos Cirúrgicos Operatórios/métodos
7.
Chir Ital ; 31(4): 602-15, 1979 Aug.
Artigo em Italiano | MEDLINE | ID: mdl-553731

RESUMO

The authors review several existing classifications of traumatic events affecting the peripheral blood vessels; after discussing the symptoms of such events and diagnostic guidelines, they outline therapeutic approaches and emphasize above all the need for prompt surgery with the least possible delay after the injury. They review of cases of their own observation, and conclude by highlighting the basic concepts of modern surgery in this field of pathology.


Assuntos
Vasos Sanguíneos/lesões , Acidentes de Trânsito , Adolescente , Adulto , Criança , Emergências , Feminino , Humanos , Masculino , Procedimentos Cirúrgicos Vasculares/métodos , Ferimentos por Arma de Fogo/cirurgia , Ferimentos Perfurantes/cirurgia
9.
Chir Ital ; 28(2): 163-70, 1976 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-1009641

RESUMO

16 patients suffering from acute pancreatitis were treated by intramuscular or intravenous administration of glucagon, with control of the amylasemia and amylasuria values at the start of treatment, the 12th hour and the 36th hour. By the 12th hour from the start of therapy they already observed a reduction in amylasemia and amylasuria to normal values, with disappearance of the symptomatology (pains, vomiting, shock) and complete cure of the patients in 94% of cases. On the basis of their own and others' experience, the Authors therefore believe that glucagon can advantageously be used in this disease, which is characterised by much higher mortality if treated with the traditional therapeutic means.


Assuntos
Glucagon/uso terapêutico , Pancreatite/tratamento farmacológico , Doença Aguda , Adulto , Idoso , Amilases/metabolismo , Avaliação de Medicamentos , Feminino , Glucagon/administração & dosagem , Humanos , Injeções Intramusculares , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade
10.
Chir Ital ; 28(2): 136-51, 1976 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-1009639

RESUMO

Using a diagnostic technique allowing thermal variations of the body surface to be translated into pictures by remote recordings (telethermography), the Authors studied a group of patients suffering from peripheral arteriopathies. The patients were also subjected to other tests (oscillography, pletysmography, electrothermometry, arteriography). The diagnostic reliability of the telethermographic procedure in the cases studied was 80% (8 cases out of 10), with 20% of false negatives. Even in the two falsely negative cases, however, the investigation proved useful, since it allowed the improvement obtained with medical and surgical therapy to be evaluated. The Authors therefore conclude by asserting that telethermography is an effective diagnostic means because of the reliability of the results and its simplicity in use, as well as being non-traumatic and hence easily repeatable.


Assuntos
Termografia , Doenças Vasculares/diagnóstico , Adulto , Idoso , Aneurisma/diagnóstico , Braço/irrigação sanguínea , Arteriosclerose/diagnóstico , Fístula Arteriovenosa/diagnóstico , Estudos de Avaliação como Assunto , Feminino , Humanos , Perna (Membro)/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Doença de Raynaud/diagnóstico
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