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1.
Acta Neurol Scand ; 137(1): 24-28, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28875555

RESUMO

OBJECTIVE: A previous European cost-utility study reported that use of buccal midazolam in the community setting for the treatment of prolonged seizures (ie, seizures lasting ≥5 minutes) in children was associated with an overall €12 507 399 reduction in annual costs charged to the Italian national health service compared with rectal diazepam. We re-evaluated these findings by applying a more conservative approach. METHODS: The Italian Delphi panel reconvened to apply a more conservative assessment of available reports. A decision-tree model was used, allowing for different treatment pathways depending on whether or not a caregiver administers treatment, an ambulance is required for transport of the child to hospital, and an inpatient stay is required. Direct medical costs were derived from Italian healthcare system data. Estimates of the annual number of prolonged tonic-clonic seizures expected in the country were based on studies which assessed seizure duration using video-EEG recordings and medical records. RESULTS: Although drug acquisition costs were greater for buccal midazolam than for rectal diazepam, the acquisition cost difference was outweighed by larger cost savings resulting mostly from a reduction in hospital admissions. Assuming that 1.2% of tonic and/or clonic seizures occurring in children and adolescents over a 12-month period are prolonged, the annual nationwide reduction in costs from preferring buccal midazolam to rectal diazepam was estimated at €3 577 587.9. CONCLUSIONS: In this more conservative revised analysis, the high cost of buccal midazolam is still counteracted by greater cost savings compared with rectal diazepam, but cost reduction was less than previously estimated.


Assuntos
Anticonvulsivantes/economia , Diazepam/economia , Midazolam/economia , Convulsões/tratamento farmacológico , Administração Bucal , Administração Retal , Adolescente , Anticonvulsivantes/administração & dosagem , Criança , Árvores de Decisões , Diazepam/administração & dosagem , Farmacoeconomia , Feminino , Humanos , Lactente , Masculino , Midazolam/administração & dosagem
2.
Neuroscience ; 317: 130-40, 2016 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-26762804

RESUMO

Multiple sclerosis is a chronic, inflammatory and demyelinating disease of the central nervous system (CNS). As there is no cure for this disease, new therapeutic strategies and prophylactic measures are necessary. We recently described the therapeutic activity of the association between myelin oligodendrocyte glycoprotein peptide (MOG) and active vitamin D3 (VitD) against experimental autoimmune encephalomyelitis (EAE). The objective of this work was to evaluate the prophylactic potential of this association in EAE. C57BL/6 mice were vaccinated with MOG in the presence of VitD and then subjected to EAE induction. Animals were euthanized 7 and 19days after disease induction and the following parameters were evaluated: body weight, clinical score, inflammatory process in the CNS, amount of dendritic cells (DCs) and regulatory T cells in the spleen and cytokine production by spleen and CNS cell cultures. Vaccination with MOG associated with VitD determined a drastic reduction in clinical score, body weight loss, CNS inflammation, DCs maturation and also in the production of cytokines by CNS and spleen cell cultures. Collectively, our data indicate that this association prevents EAE development. A similar effect from specific self-antigens associated with VitD is expected in other autoimmune conditions and deserves to be experimentally appraised.


Assuntos
Sistema Nervoso Central/patologia , Encefalomielite Autoimune Experimental/prevenção & controle , Glicoproteína Mielina-Oligodendrócito/toxicidade , Vitamina D/administração & dosagem , Vitaminas/administração & dosagem , Animais , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Relação Dose-Resposta Imunológica , Esquema de Medicação , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/patologia , Feminino , Citometria de Fluxo , Adjuvante de Freund/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Glicoproteína Mielina-Oligodendrócito/imunologia , Neurônios/metabolismo , Baço/patologia , Fatores de Tempo
3.
Trop Biomed ; 33(3): 526-534, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33579126

RESUMO

Prevalence of allergic and autoimmune pathologies is clearly increasing in developed countries. This has been attributed to a decreased exposure to certain microorganisms and been referred as hygiene hypothesis. In this study we evaluated if a previous infection with Strongyloides venezuelensis would alter the progression of experimental autoimmune encephalomyelitis (EAE) in Lewis rats. Animals were initially infected with 4000 L3 infective larvae of S. venezuelensis by subcutaneous route. Encephalomyelitis was then induced during the acute phase of the infection by immunization with myelin basic protein emulsified with Complete Freund's Adjuvant plus Mycobacterium butyricum. Previous infection downmodulated cytokine production but did not change clinical and histopathological EAE manifestations. Cytometric analysis with antibodies specific for CD4+CD25+Foxp3+ regulatory T cells indicated that infection also did not alter the frequency of these cells in spleen and regional lymph nodes. This finding could partly explain the failure of this worm to avoid EAE progression. Altogether these results demonstrated that infection with S. venezuelensis was not able to modify EAE progression in Lewis rats. In the context of the hygiene hypothesis, these results reinforce the necessity of a comparative study among different helminth species to identify the ones with immunoregulatory competence.

4.
Clin Exp Immunol ; 173(3): 430-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23692306

RESUMO

Type I diabetes is a disease caused by autoimmune destruction of the beta cells in the pancreas that leads to a deficiency in insulin production. The aim of this study was to evaluate the prophylactic potential of a prime-boost strategy involving bacille Calmette-Guérin (BCG) and the pVAXhsp65 vaccine (BCG/DNAhsp65) in diabetes induced by streptozotocin (STZ) in C57BL/6 mice and also in spontaneous type 1 diabetes in non-obese diabetic (NOD) mice. BCG/DNAhsp65 vaccination in NOD mice determined weight gain, protection against hyperglycaemia, decreased islet inflammation, higher levels of cytokine production by the spleen and a reduced number of regulatory T cells in the spleen compared with non-immunized NOD mice. In the STZ model, however, there was no significant difference in the clinical parameters. Although this vaccination strategy did not protect mice in the STZ model, it was very effective in NOD mice. This is the first report demonstrating that a prime-boost strategy could be explored as an immunomodulatory procedure in autoimmune diseases.


Assuntos
Vacina BCG/imunologia , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Tipo 1/imunologia , Animais , Vacina BCG/genética , Citocinas/biossíntese , Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 1/prevenção & controle , Feminino , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Estreptozocina/efeitos adversos , Linfócitos T Reguladores/imunologia
5.
Parasite Immunol ; 33(5): 303-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21477142

RESUMO

According to the hygiene hypothesis, the increased incidence of allergic and autoimmune diseases in developed countries is mainly explained by the decreased contact between the human population and certain environmental agents as lactobacillus, mycobacteria and helminths. In this study, we evaluated the effect of multiple infections with Strongyloides venezuelensis on the development of experimental autoimmune encephalomyelitis (EAE) in Lewis rats. Multiple infections before EAE induction were not able to change the evolution of the disease. No alterations were observed in weight loss, clinical score and inflammation intensity at the central nervous system. The presence of significant levels of parasite-specific IgG1 but not IgG2b suggested a Th2 polarization. However, the percentage and absolute number of CD4+CD25+Foxp3+ T cells were not changed, being their levels in the spleen and lymph nodes of infected rats comparable to the ones found in normal animals. These results suggest that a Th2-polarized response without concomitant expansion of Foxp3+ regulatory T cells was not able to modify EAE progression. Even though these results do not threaten the hygiene hypothesis, they suggest that this paradigm might be an oversimplification. They also emphasize the need of a study to compare the immunoregulatory ability associated with different helminth spp.


Assuntos
Encefalomielite Autoimune Experimental/complicações , Encefalomielite Autoimune Experimental/patologia , Strongyloides/patogenicidade , Estrongiloidíase/complicações , Estrongiloidíase/patologia , Animais , Anticorpos Anti-Helmínticos/sangue , Peso Corporal , Antígenos CD4/análise , Sistema Nervoso Central/patologia , Feminino , Fatores de Transcrição Forkhead/análise , Imunoglobulina G/sangue , Subunidade alfa de Receptor de Interleucina-2/análise , Ratos , Índice de Gravidade de Doença , Subpopulações de Linfócitos T/química , Subpopulações de Linfócitos T/imunologia , Células Th2/imunologia
6.
Neurol Sci ; 31(6): 859-61, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20390435

RESUMO

Wernicke's encephalopathy (WE) is an acute or subacute syndrome that results from a deficiency in vitamin B1 (thiamine). The syndrome is characterised by a classical triad of symptoms: nystagmus and ophthalmoplegia,mental-status changes, and unsteadiness of stance and gait. When patients with WE are inappropriately treated with low doses of thiamine, mortality rates average out at 20% and Korsakoff's Psychosis develops in about 85% of survivors(Sechi and Serra in Lancet Neurol 6(5):442­455,2007). We report the case of a patient with a pyloric substenosis that developed a WE, and was treated with high doses of thiamine showing after few days of treatment a great improvement of neurological and neuroradiological assessment, even though cognitive impairment was still severe at discharge and at 6 months follow-up.


Assuntos
Estenose Pilórica/complicações , Tiamina/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Encefalopatia de Wernicke/complicações , Encefalopatia de Wernicke/tratamento farmacológico , Relação Dose-Resposta a Droga , Humanos , Masculino , Pessoa de Meia-Idade , Estenose Pilórica/diagnóstico , Estenose Pilórica/tratamento farmacológico , Encefalopatia de Wernicke/diagnóstico
7.
Parasite Immunol ; 32(1): 74-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20042010

RESUMO

In this study, we investigated the characteristics of the infection and subsequent immunity induced by Strongyloides venezuelensis in Lewis rats. Animals were infected with 4000 L3 of S. venezuelensis and number of eggs per gram of faeces indicated an acute phase around day 8 and a recovery phase around day 32 after infection. A strong Th2 polarization during recovery phase was ascertained by a significant increase in IgG1 and IgE compared with that in the acute period. A shift in the cytokine profile confirmed these findings. A predominant production of IFN-gamma during the acute phase was followed by IL-10 production during recovery. Together these findings show that experimental infection of Lewis rats with S. venezuelensis presents a kinetics of parasite establishment and immunity similar to that described in other models of helminthic infection.


Assuntos
Strongyloides/imunologia , Estrongiloidíase/imunologia , Células Th2/imunologia , Doença Aguda , Animais , Fezes/parasitologia , Feminino , Humanos , Imunidade Celular , Imunoglobulina E/biossíntese , Imunoglobulina G/biossíntese , Interferon gama/biossíntese , Interleucina-10/biossíntese , Contagem de Ovos de Parasitas , Ratos , Ratos Endogâmicos Lew , Remissão Espontânea , Estrongiloidíase/parasitologia , Estrongiloidíase/patologia , Células Th2/metabolismo , Células Th2/patologia , Fatores de Tempo
8.
J. venom. anim. toxins incl. trop. dis ; 15(3): 374-390, 2009. ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: lil-525828

RESUMO

Malnutrition may be a consequence of energy deficit or micronutrient deficiency. It is considered the most relevant risk factor for illness and death, particularly in developing countries. In this review we described the magnitude of this problem, as well as its direct effect on the immune system and how it results in higher susceptibility to infections. A special emphasis was given to experimental models used to investigate the relationship between undernutrition and immunity. Malnutrition is obviously a challenge that must be addressed to health authorities and the scientific community.(AU)


Assuntos
Micronutrientes , Desnutrição , Sistema Imunitário , Modelos Teóricos , Fatores de Risco
9.
Neurol Sci ; 27 Suppl 1: S52-4, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16708186

RESUMO

Status epilepticus (SE) is a medical emergency. It requires prompt and adequate diagnosis and treatment, as it may induce CNS injury. It is mainly distinguished into generalised and partial SE on the basis of its major clinical features. There are very few data about SE physiopathology, but it is generally characterised by increasing unresponsiveness to treatment. SE diagnosis is based on EEG recording, associated with neuroimaging techniques and laboratory assays to detect underlying pathologies. During SE we distinguish three different conditions: initial, defined and refractory. Benzodiazepines represent first-line treatment, followed by phenytoin. Refractory SE requires ICU treatment to perform general anaesthesia.


Assuntos
Estado Epiléptico , Humanos , Estado Epiléptico/patologia , Estado Epiléptico/fisiopatologia , Estado Epiléptico/terapia
10.
Clin Neurophysiol ; 116(11): 2577-85, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16214407

RESUMO

OBJECTIVE: The aim of this study is to evaluate the usefulness of a spectral function detecting cerebral hypoperfusion. METHODS: Continuous electroencephalographic monitoring was employed during 47 consecutive carotid endarterectomies. Patients were assigned to 3 different groups according to the entity of electroencephalographic changes during carotid clamping (major changes: group A; moderate changes: group B; no change: group C). The desynchronization function, indicating the reduction of the 8-15 Hz band power, and the desynchronization index were calculated. RESULTS: Group A function decreased within 20s from clamping, with a constant slope (7.14). Desynchronization indexes were: 76.85% (group A), 40.23% (group B) and 15.29% (group C). Difference among groups was statistically significant (P < 0.0001). A case of syncope due to asystole is also reported, showing the same pattern in the descending phase of the function. CONCLUSIONS: The stereotyped time course of the desynchronization function describes the cerebral reaction to significant blood flow reduction. Values of desynchronization index exceeding 65% seem to correctly detect patients with cerebral hypoxic risk. SIGNIFICANCE: The analysis of the 8-15 Hz band desynchronization is helpful in the evaluation of cerebral hypoperfusion during carotid endarterectomy. This method could be employed in monitoring different clinical situations of ischemia.


Assuntos
Artérias Carótidas/cirurgia , Circulação Cerebrovascular , Sincronização Cortical , Eletroencefalografia , Endarterectomia , Idoso , Constrição , Feminino , Parada Cardíaca/complicações , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Síncope/etiologia , Síncope/fisiopatologia
11.
Diabetes ; 50(3): 496-501, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11246868

RESUMO

Cardiovascular disease and the development of coronary artery disease play a pivotal role in increasing mortality in patients with type 1 diabetes. The aim of our study was to evaluate the effects of pancreas transplantation on atherosclerotic risk factors, endothelial-dependent dilation (EDD), and progression of intima media thickness (IMT) in patients with uremia and type 1 diabetes after kidney-alone (KA) or kidney-pancreas (KP) transplantation. A cross-sectional study comparing two groups of patients with type 1 diabetes was performed. Sixty patients underwent KP transplantation and 30 patients underwent KA transplantation. Age and cardiovascular risk profile were comparable in patients before transplantation. In all patients, atherosclerotic risks factors (lipid profile, fasting and post-methionine load plasma homocysteine, von Willebrand factor levels, D-dimer fragments, and fibrinogen) were assessed and Doppler echographic evaluation of IMT and endothelial function with flow-mediated and nitrate dilation of the brachial artery was performed. Twenty healthy subjects were chosen as controls (C) for EDD. Compared with patients undergoing KA transplantation, patients undergoing KP transplantation showed lower values for HbA1c (KP = 6.2 +/- 0.1% vs. KA = 8.4 +/- 0.5%; P < 0.01), fasting homocysteine (KP = 14.0 +/- 0.7 mcromol/l vs. KA = 19.0 +/- 2.0 micromol/l; P = 0.02), von Willebrand factor levels (KP = 157.9 +/- 8.6% vs. KA = 212.5 +/- 16.2%; P < 0.01), D-dimer fragments (KP = 0.29 +/- 0.02 microg/ml vs. KA = 0.73 +/- 0.11 microg/ml;P < 0.01), fibrinogen (KP = 363.0 +/- 11.1 mg/dl vs. KA = 397.6 +/- 19.4 mg/dl; NS), triglycerides (KP = 122.7 +/- 8.6 mg/dl vs. KA = 187.0 +/- 30.1 mg/dl; P = 0.01), and urinary albumin excretion rate (KP = 13.5 +/- 1.9 mg/24 h vs. KA = 57.3 +/- 26.3 mg/24 h; P < 0.01). Patients undergoing KP transplantation showed a normal EDD (KP = 6.21 +/- 2.42%, KA = 0.65 +/- 2.74%, C = 8.1 +/- 2.1%; P < 0.01), whereas no differences were observed in nitrate-dependent dilation. Moreover, IMT was lower in patients undergoing KP transplantation than in patients undergoing KA transplantation (KP = 0.74 +/- 0.03 mm vs. KA = 0.86 +/- 0.09 mm; P = 0.04). Our study showed that patients with type 1 diabetes have a lower atherosclerotic risk profile after KP transplantation than after KA transplantation. These differences are tightly correlated with metabolic control, fasting homocysteine levels, lower D-dimer fragments, and lower von Willebrand factor levels. Normal endothelial function and reduction of IMT was observed only in patients undergoing KP transplantation.


Assuntos
Arteriosclerose/etiologia , Diabetes Mellitus Tipo 1/complicações , Endotélio Vascular/fisiopatologia , Transplante de Rim , Transplante de Pâncreas , Uremia/complicações , Adulto , Diabetes Mellitus Tipo 1/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Trombose/etiologia , Uremia/fisiopatologia
12.
J Clin Neurophysiol ; 17(1): 101-7, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10709815

RESUMO

The purpose of this study was to develop a reliable method of EEG analysis during carotid endarterectomy. EEGs of 104 patients under general anesthesia were processed by three different methods: a) "on-line" visual analysis during surgery, b) "off-line" visual analysis in laboratory, and c) computer analysis. To identify pathological EEGs, variability and asymmetry indexes of the 0.5-3.5 Hz and 8-15 Hz bands, absolute power and variability indexes of spectral edge frequency (SEF), and main dominant frequency were evaluated. On-line visual analysis showed clamp-related modifications in 29 EEGs (27.9%). Off-line visual analysis detected 24 pathological EEGs (23.1%): 18 with major changes and 6 with moderate changes. Computer analysis showed 21 EEGs (20.19%) with at least one altered index and 7 (6.7%) with altered variability for both SEF and 8-15 Hz power. The statistical analysis was significant for SEF variability and for 8-15 Hz power variability and asymmetry (P < 0.0001, analysis of variance test). While SEF and 8-15 Hz power variability did not appear influenced by anesthesia and single electrode artifacts, 8-15 Hz power asymmetry index was confounded by the presence of contralateral internal carotid occlusion. The data show that the use of these spectral indexes adds objective information to visual analysis, supporting and making easier intraoperative strategies. Their routine clinical use does not involve additional costs remaining technical requirements unchanged compared to traditional recording.


Assuntos
Diagnóstico por Computador/métodos , Eletroencefalografia/métodos , Endarterectomia das Carótidas/métodos , Monitorização Intraoperatória/métodos , Idoso , Idoso de 80 Anos ou mais , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Epilepsia ; 39(9): 942-51, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9738673

RESUMO

PURPOSE: The chromosome 20 ring [r(20)] is a rare chromosomal disorder without clear phenotypical markers. We describe the electroclinical pattern in a group of patients with r(20). METHODS: We observed 3 patients (a boy, patient 1; his mother, patient 2; and an unrelated man, patient 3), performing prolonged video-EEG and cytogenetic studies and fluorescent in situ hybridization (FISH) with chromosome-specific telomeric probes. RESULTS: All 3 patients had a very similar abnormal electroclinical pattern characterized by long bursts or trains of rhythmic theta waves, which were sharply contoured or had a notched appearance (with no detectable clinical correlate), and generalized spike waves (SW) associated with seizures of probable frontotemporal origin (SFT). In all 3 patients, the cytogenetic analysis of T lymphocytes showed mosaicism with a normal cell line and a second cell line with a chromosome 20, although the latter was little represented in patients 2 and 3. A few cells with a single chromosome 20 were also found. The same cytogenetic findings were confirmed in the lymphoblastoid cell line of patient 1 and in the fibroblasts of patient 3. FISH with chromosome-specific telomeric probes and TTAGGG sequences demonstrated the integrity of the ring chromosomes. CONCLUSIONS: The clinical picture of these patients appears to be related to the instability of the r(20)-generating cells monosomic for chromosome 20 and is thus haploinsufficient for a gene. In these patients, the electroclinical pattern of theta waves (probably unrelated to epilepsy) and the SW and SFT, even with mild mental retardation (MR) or no MR and without dysmorphic features, suggest that the r(20) syndrome may be present.


Assuntos
Cromossomos Humanos Par 20/genética , Eletroencefalografia/estatística & dados numéricos , Cromossomos em Anel , Convulsões/diagnóstico , Adolescente , Adulto , Aberrações Cromossômicas/diagnóstico , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Mapeamento Cromossômico , Epilepsia/diagnóstico , Epilepsia/genética , Humanos , Hibridização In Situ , Deficiência Intelectual/genética , Masculino , Sequências Repetitivas de Ácido Nucleico , Convulsões/genética , Síndrome , Telômero
14.
Int J Cardiol ; 63(2): 175-8, 1998 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-9510492

RESUMO

This perspective study was performed to demonstrate the prevention of left ventricular hypertrophy by ACE-inhibitor, ramipril, in hypertensives of recent onset. Thirty-four hypertensive patients, treated with ramipril (group I), and 32 controls who received another frequently employed drug (the calcium channel-antagonist, felodipine (group II), were evaluated. Neither of two groups received any anti-hypertensive drug and did not suffer from left ventricular hypertrophy. All selected patients underwent M-mode echocardiography for measuring the following parameters: diastolic diameter of left ventricle, (DDLV); systolic diameter of left ventricle (SDLV); inter-ventricular septum (IVS); thickness of the posterior wall (PW); and left ventricular mass index (LVMI). Two anti-hypertensive drugs reduce systemic hypertension the same way. But, in hypertensives receiving ramipril (group I), the echocardiographic parameters of the left ventricle increased non-significantly. On the other hand, in those treated with felodipine (II group), these parameters significantly changed. The mechanisms of non-increase in cardiac and non-cardiac proteins, due to the ACE-inhibitors, are illustrated.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Felodipino/uso terapêutico , Hipertrofia Ventricular Esquerda/prevenção & controle , Ramipril/uso terapêutico , Adulto , Ecocardiografia , Feminino , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Resultado do Tratamento
15.
Ital J Neurol Sci ; 19(4): 211-6, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10933459

RESUMO

The electroencephalographic modifications that occur during the course of Alzheimer's disease are characterised by an increase in the potential of low frequency bands, a diminution in the potential of alpha activity, and a change in the topographical distribution of the potential of all band frequencies. In this study, the fast Fourier transform (FFT) approximation was used to characterise modifications in the electroencephalogram location or orientation of the source of the dipole equivalent of the delta, theta, alpha1, alpha2, beta1 and beta2 frequencies in 20 with patients with Alzheimer's disease and in a control group of 20 age-matched subjects. A statistical (t-test) comparison of the two groups revealed a significant change in the location of the dipolar source along the vertical axis in 18 (90%) of the patients; this change involved all the frequency bands. There was also a significant movement of the dipolar source of the alpha1 band towards the anterior regions. In addition, the control group showed that there was a significant correlation between age and a more surface expression of the source of the delta, theta, alpha1 and beta1 bands.


Assuntos
Doença de Alzheimer/diagnóstico , Eletroencefalografia , Fatores Etários , Idoso , Ritmo alfa , Ritmo Delta , Diagnóstico Diferencial , Humanos , Pessoa de Meia-Idade , Ritmo Teta
16.
Eur J Nucl Med ; 23(11): 1498-507, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8854849

RESUMO

The aim of this study was to evaluate, in 16 patients with drug-resistant partial epilepsy who were waiting to undergo surgical treatment, the relation between positron emission tomography (PET) findings with fluorine-18 fluorodeoxyglucose ([18F]FDG) in the interictal state and the different stereo-electroencephalography (SEEG) patterns that characterize: (a) the epileptogenic zone (low-voltage fast-activity discharge before or concurrent with ictal clinical symptoms), (b) the irritative zone (spikes, spikes and waves, isolated or grouped in short bursts) and (c) the lesional zone (continuous, sometimes polyrhythmic slow waves or continuous delta waves or very important voltage depression). SEEG was performed following an individually defined electrode implantation strategy. Whereas at least one area of hypometabolism was detected by visual interpretation of PET/[18F]FDG images in all the subjects in the study, there was poor agreement between PET/[18F]FDG quantitative measures of regional metabolism and SEEG findings. Normal metabolic rates were found in up to 62% of the areas with abnormal SEEG activity, independent of the type of electrical activity, i.e. epileptogenic, irritative, or lesional, while abnormal metabolic rates were found in up to 23% of the areas with normal SEEG activity. In conclusion, whereas the visual interpretation of interictal studies of glucose utilization in our series of drug-resistant epileptic patients consistently allowed the localization of an area of temporal hypometabolism, the quantitative and regional metabolic analysis demonstrated that such a finding is not specifically related to any of the three very different SEEG patterns (epileptogenic, irritative, lesional) or combinations thereof. These results complement those of previous interictal and ictal single-photon emission tomographic studies and of receptor studies in epileptics, suggesting functional and biochemical heterogeneity within the interictal hypoperfused/hypometabolic area in epileptic patients, and contribute to the debate on the use and interpretation of interictal PET/[18F]FDG studies in patients with medically refractory partial seizures.


Assuntos
Desoxiglucose/análogos & derivados , Eletroencefalografia/métodos , Epilepsias Parciais/diagnóstico , Radioisótopos de Flúor , Tomografia Computadorizada de Emissão , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Epilepsias Parciais/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino
17.
Technol Health Care ; 4(2): 169-85, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8885095

RESUMO

A method for the analysis of variability of EEG signals is described. We examined simulated signals and real EEGs obtained from a normal subject and two epileptic patients. The first step of the method is based on autoregressive (AR) modelling of short EEG epochs. Prediction coefficients of the AR model were computed as a function of time from partially-overlapping moving windows of 2 s duration. The temporal behaviour of these coefficients was analysed to detect variability: quasi-stationary activity causes only smooth changes in the coefficients while variations in the amplitude and/or the frequency content of the signal are shown to produce sharp changes in the coefficients. A segmentation algorithm was developed to detect and quantify with a numerical value (Difference Measure, DM) the AR coefficients variations.


Assuntos
Eletroencefalografia , Epilepsia/diagnóstico , Modelos Estatísticos , Processamento de Sinais Assistido por Computador , Algoritmos , Estudos de Casos e Controles , Humanos , Valor Preditivo dos Testes , Análise de Regressão , Reprodutibilidade dos Testes , Fatores de Tempo
20.
J Neurol Neurosurg Psychiatry ; 59(4): 427-31, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7561924

RESUMO

Positron emission tomography with [18F]-2-fluoro-2-deoxy-D-glucose ([18F]FDG) has been used to assess the pattern of cerebral metabolism in different types of epilepsies. However, PET with [18F]FDG has never been used to evaluate drug naive patients with cryptogenic temporal lobe epilepsy, in whom the mechanism of origin and diffusion of the epileptic discharge may differ from that underlying other epilepsies. In a group of patients with cryptogenic temporal lobe epilepsy, never treated with antiepileptic drugs, evidence has been found of significant interictal glucose hypermetabolism in a bilateral neural network including the temporal lobes, thalami, basal ganglia, and cingular cortices. The metabolism in these areas and frontal lateral cortex enables the correct classification of all patients with temporal lobe epilepsy and controls by discriminant function analysis. Other cortical areas--namely, frontal basal and lateral, temporal mesial, and cerebellar cortices--had bilateral increases of glucose metabolism ranging from 10 to 15% of normal controls, although lacking stringent statistical significance. This metabolic pattern could represent a pathophysiological state of hyperactivity predisposing to epileptic discharge generation or diffusion, or else a network of inhibitory circuits activated to prevent the diffusion of the epileptic discharge.


Assuntos
3-O-Metilglucose/análogos & derivados , Encéfalo/metabolismo , Epilepsia do Lobo Temporal/metabolismo , Glucose/metabolismo , Rede Nervosa/metabolismo , Adolescente , Adulto , Análise de Variância , Encéfalo/diagnóstico por imagem , Epilepsia do Lobo Temporal/diagnóstico por imagem , Feminino , Radioisótopos de Flúor , Humanos , Masculino , Metilglucosídeos , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Tomografia Computadorizada de Emissão
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