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1.
Int J Neurosci ; 126(4): 354-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26000822

RESUMO

OBJECTIVE: Iron homeostasis appears altered in Parkinson's disease (PD). Recent genetic studies and meta-analyses have produced heterogeneous and inconclusive results. In order to verify the possible role of iron status in PD, we have screened some of the main metal gene variants, evaluated their effects on iron systemic status, and checked for possible interactions with PD. MATERIALS AND METHODS: In 92 PD patients and 112 healthy controls, we screened the D544E and R793H variants of the ceruloplasmin gene (CP), the P589S variant of the transferrin gene (TF), and the H63D and C282Y variants of the HFE gene, encoding for homologous proteins, respectively. Furthermore, we analyzed serum concentrations of iron, copper and their related proteins. RESULTS: The genetic investigation revealed no significant differences in allelic and genotype distributions between patients and controls. Two different multivariable forward stepwise logistic models showed that, when the effect of sex is considered, an increase of the probability of having PD is associated with low iron concentration and Tf-saturation. CONCLUSIONS: This study provides new evidence of the involvement of iron metabolism in PD pathogenesis and reveals a biological effect of sex.


Assuntos
Ceruloplasmina/genética , Proteína da Hemocromatose/genética , Ferro/sangue , Doença de Parkinson/genética , Transferrina/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Casos e Controles , Cobre/sangue , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/sangue , Polimorfismo Genético , Caracteres Sexuais
2.
J Neurol ; 270(2): 986-994, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36326890

RESUMO

INTRODUCTION: Although migraine prevalence decreases with aging, some older patients still suffer from chronic migraine (CM). This study aimed to investigate the outcome of OnabotulinumtoxinA (OBT-A) as preventative therapy in elderly CM patients. METHODS: This is a post hoc analysis of real-life prospectively collected data at 16 European headache centers on CM patients treated with OBT-A over the first three treatment cycles (i.e., Cy1-3). We defined: OLD patients aged ≥ 65 years and nonOLD those < 65-year-old. The primary endpoint was the changes in monthly headache days (MHDs) from baseline to Cy 1-3 in OLD compared with nonOLD participants. The secondary endpoints were the responder rate (RR) ≥ 50%, conversion to episodic migraine (EM) and the changes in days with acute medication use (DAMs). RESULTS: In a cohort of 2831 CM patients, 235 were OLD (8.3%, 73.2% females, 69.6 years SD 4.7). MHDs decreased from baseline (24.8 SD 6.2) to Cy-1 (17.5 SD 9.1, p < 0.000001), from Cy-1 to Cy-2 (14.8 SD 9.2, p < 0.0001), and from Cy-2 to Cy-3 (11.9 SD 7.9, p = 0.001). DAMs progressively reduced from baseline (19.2 SD 9.8) to Cy-1 (11.9 SD 8.8, p < 0.00001), to Cy-2 (10.9 SD 8.6, p = 0.012), to Cy-3 (9.6 SD 7.4, p = 0.049). The 50%RR increased from 30.7% (Cy-1) to 34.5% (Cy-2), to 38.7% (Cy-3). The above outcome measures did not differ in OLD compared with nonOLD patients. CONCLUSION: In a population of elderly CM patients with a long history of migraine OBT-A provided a significant benefit, over the first three treatment cycles, as good as in non-old patients.


Assuntos
Toxinas Botulínicas Tipo A , Transtornos de Enxaqueca , Idoso , Feminino , Humanos , Masculino , Toxinas Botulínicas Tipo A/uso terapêutico , Doença Crônica , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/epidemiologia , Cefaleia/tratamento farmacológico , Resultado do Tratamento
3.
Int J Immunopathol Pharmacol ; 25(4): 1157-65, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23298507

RESUMO

Neuropsychiatric manifestations are not rarely associated with systemic lupus erythematosus (SLE). Magnetic resonance angiography and positron emission tomography can provide excellent images of cerebral perfusion and metabolism whereas information is still lacking on a possible diagnostic role of ultrasound. In this study we aim to assess whether duplex sonography of neck and intracranial vessels may be useful in distinguishing patients with and without neuropsychiatric SLE (NPSLE). Neck and transcranial duplex sonography was performed by a single operator on 33 women affected by SLE (mean age +/- SD: 47.69+/-8.17 years) and on 15 healthy control subjects. Nineteen patients presented NPSLE. Pulsatility and resistivity indices (PI and RI) were automatically calculated by the ultrasound instrument in internal carotid (ICA) and middle cerebral artery (MCA), on both sides, according to standard methods. No significant haemodynamic differences were found in mean and median PI and RI values of ICA and MCA comparing SLE with NPSLE patients and with healthy control subjects. No correlation was found between MCA and ICA parameters in the same group of patients. Duplex sonography of cerebral vessels is unable to distinguish SLE and NPSLE patients. Heterogeneity of causes in the pathogenesis of NPSLE and the different vascular adaptation of cerebral macrocirculation as opposed to cerebral microcirculation may represent possible reasons that explain the inability of ultrasound to differentiate SLE patients from NPSLE patients.


Assuntos
Ecoencefalografia , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico por imagem , Adulto , Idoso , Artéria Carótida Interna/fisiopatologia , Artérias Cerebrais/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Epilepsy Behav ; 23(3): 342-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22377332

RESUMO

The prevalence and characteristics of interictal headache, epilepsy and headache/epilepsy comorbidity were assessed in 858 women and 309 men aged 18-81 years from headache and epilepsy centers in Italy. The research hypothesis was that comorbidity among patients with either disorder would be expected to be higher than in the general population. Interictal headache was diagnosed in 675 cases (migraine 482; tension-type headache 168; other types 25), epilepsy in 336 (partial 171; generalized 165) and comorbidity in 156 (1.6% from headache centers; 30.0% from epilepsy centers). Patients with epilepsy, headache and comorbidity differed in a number of demographic and clinical aspects. However, for both headache and epilepsy, a family history of the same clinical condition was equally prevalent in patients with and without comorbidity. These findings do not support the purported association between headache and epilepsy.


Assuntos
Epilepsia/epidemiologia , Transtornos da Cefaleia Primários/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Comorbidade , Estudos Transversais , Epilepsia/diagnóstico , Feminino , Transtornos da Cefaleia Primários/classificação , Transtornos da Cefaleia Primários/diagnóstico , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
5.
Eur J Neurol ; 16(1): 81-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19087154

RESUMO

BACKGROUND AND PURPOSE: Aim of our study was to evaluate cerebral hemodynamic changes during performance of attention tasks and to correlate them with reaction time (RT) and percentage of right answers. METHODS: Mean flow velocity (MFV) in middle cerebral arteries was monitored in 30 subjects by transcranial Doppler during tonic alertness, phasic alertness, focused and divided attention tasks. RESULTS: Mean flow velocity increase was significantly higher during divided attention with respect to other tasks (P < .001). MFV increase was higher in the right than in the left side (P < .001). Asymmetry during attention tasks resulted significantly higher than that observed in tonic alertness condition. RT was increased during focused attention tasks (P < .001 vs. both alert tasks), with further increase during divided attention tasks (P < .001 vs. focused attention task). RT was inversely related to MFV increase only during tonic alertness (P = 0.012 for left side; P = 0.008 for right side). During the divided attention tasks, an association was found between MFV increase and correct answers (r = 0.39, P = 0.033). CONCLUSIONS: These data show a relationship between RT, correct answers and changes in blood flow velocity and suggest that this method of cerebral blood flow investigation could be a useful approach during assessment of patients with attention deficit.


Assuntos
Atenção/fisiologia , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/fisiologia , Circulação Cerebrovascular/fisiologia , Ultrassonografia Doppler Transcraniana/métodos , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Adulto Jovem
6.
Mult Scler Relat Disord ; 27: 344-349, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30472414

RESUMO

BACKGROUNG: Multiple sclerosis (MS) results in a broad range of symptoms, including motor, visual, cognitive, and neuropsychiatric deficits. Some studies, considering affective facial expressions to study emotion processing, demonstrated emotion recognition difficulties in MS patients. OBJECTIVE: We investigated the impact of MS on the emotional-behaviour rating and neurophysiological response (Event Related Potentials-ERP) through a battery of affective visual stimuli selected from the International Affective Picture System (IAPS). METHODS: Twenty patients with diagnosis of Relapsing Remitting MS (RRMS) and 20 Healthy Controls (HC) matched by age, gender and education were enrolled. Each of them, after a neuropsychological assessment, were asked to evaluate arousal and valence of affective visual stimuli. RESULTS: Our results showed higher P300 amplitudes in RRMS patients than HC group for pleasant and unpleasant images. Moreover, RRMS patients showed lower Reaction Time (RT) respect HC in valence rating. No other effect did emerge between groups. CONCLUSION: Our study shows early compensatory cerebral mechanisms in RRMS patients throughout emotional information processing, particularly for unpleasant and pleasant stimuli. We hypothesize that this compensatory cerebral mechanism reduces the behavioural dissimilarity between patients and HC.


Assuntos
Afeto , Córtex Cerebral/fisiopatologia , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Esclerose Múltipla Recidivante-Remitente/psicologia , Adulto , Eletroencefalografia , Potenciais Evocados P300 , Potenciais Evocados Visuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estimulação Luminosa , Tempo de Reação , Percepção Visual/fisiologia
7.
Cephalalgia ; 28(7): 689-95, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18460006

RESUMO

Migraine with aura (MA) is associated with changes in cerebral blood flow (CBF), whereas the role of cerebral autoregulation is uncertain. This study aimed to evaluate basal CBF, cerebral blood volume (CBV) and vasomotor reactivity (VMR) in MA patients. Twenty-one controls and 16 MA patients (eight with side predominance) underwent simultaneous examination of flow velocity in the middle cerebral arteries by transcranial Doppler (TCD) and of near-infrared spectroscopy (NIRS) parameters [oxygen haemoglobin saturation: oxygen%, and total haemoglobin content (THC)] at rest and after hypercapnia. Cerebral VMR, THC and oxygen% increases were significantly greater on the predominant compared with the non-predominant migraine side, with both sides of patients without side predominance and with controls. These findings suggest altered autoregulation in MA patients, possibly secondary to impaired cerebrovascular autonomic control. Simultaneous TCD and NIRS investigation could represent a non-invasive approach to evaluate cerebral haemodynamics at the cortical and subcortical level.


Assuntos
Circulação Cerebrovascular/fisiologia , Homeostase/fisiologia , Enxaqueca com Aura/fisiopatologia , Oxigênio/sangue , Oxiemoglobinas/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler Transcraniana , Sistema Vasomotor/fisiopatologia , Adulto , Sistema Nervoso Autônomo/fisiopatologia , Velocidade do Fluxo Sanguíneo/fisiologia , Dominância Cerebral/fisiologia , Feminino , Hemodinâmica/fisiologia , Humanos , Hipercapnia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiopatologia , Enxaqueca com Aura/diagnóstico por imagem , Valores de Referência
8.
J Neurol ; 255(1): 94-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18080850

RESUMO

Production of reactive oxygen species after cerebral blood flow disruption may enhance tissue damage through multiple molecular pathways. Changes in nitric oxide (NO) metabolism and oxidative stress status were investigated in 47 patients with ischemic stroke by measuring plasma nitric oxide (NO) and peroxynitrite (ONOO(-)) levels.A correlation was sought between these two parameters and i) baseline stroke severity based on the National Institute of Health stroke scale (NIHSS) and ii) neurological outcome in terms of NIHSS changes from entry (T(0)) to 30 days after symptom onset (T(1)). The control group consisted of 30 age- and sex-matched healthy subjects. Mean plasma levels of ONOO(-) (arbitrary fluorescence number +/- SD) were significantly higher in patients (7.70 +/- 1.71 vs 5.35 +/- 0.69, p < 0.001), whereas mean NO levels (nmol/mg protein) were significantly higher in controls (115.40 +/- 12.40 vs. 51.10 +/- 12.50, p < 0.001). Plasma ONOO(-) was significantly higher among patients with non-lacunar stroke (8.48 +/- 1.50 vs. 6.95 +/- 1.58 in those with lacunar stroke; p = 0.001), whereas NO levels were significantly higher among lacunar stroke patients (60.00 +/- 7.86, vs. 41.77 +/- 9.29 in patients with nonlacunar stroke; p < 0.001). Nitric oxide plasma levels were also associated with an unfavorable evolution in non-lacunar stroke, since a 10 unit increase in NO predicted a 1 point reduction in the NIHSS score at T1. Findings show that changes in NO metabolism may be considered as markers of brain injury in patients with ischemic stroke. Further work is needed to establish whether the amount of biochemical changes related to oxidative stress may influence outcome in these patients.


Assuntos
Encéfalo/metabolismo , Encéfalo/fisiopatologia , Óxido Nítrico/sangue , Estresse Oxidativo/fisiologia , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/fisiopatologia , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Biomarcadores/sangue , Infarto Encefálico/sangue , Infarto Encefálico/fisiopatologia , Isquemia Encefálica/sangue , Isquemia Encefálica/fisiopatologia , Progressão da Doença , Feminino , Radicais Livres/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Peroxinitroso/sangue , Índice de Gravidade de Doença , Regulação para Cima/fisiologia
9.
Eur J Neurol ; 14(6): 679-82, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17539949

RESUMO

Evidence suggests the important role of vascular factors both in vascular dementia (VaD) and Alzheimer disease (AD) pathogenesis. However, the relationship between apolipoprotein E (APOE) polymorphism and markers of atherosclerosis is still controversial. The aim of the study was to investigate the interplay between APOE polymorphisms and atherosclerosis in patients with AD and VaD. In this cross-sectional study, 101 demented (68 AD and 33 VaD) patients underwent APOE genotyping and neck vessel ultrasound to evaluate carotid artery disease [intima-media thickness (IMT) and plaques]. Patients with AD carrying epsilon4 allele presented increased IMT values with respect to non-epsilon4 carriers and VaD patients, whereas no relation was found between APOE polymorphisms and the presence or grade of carotid plaques both in AD and VaD patients. The epsilon4 APOE allele may promote intima-media thickening, interacting with other factors contributing to AD development.


Assuntos
Doença de Alzheimer/genética , Apolipoproteína E4/genética , Aterosclerose/genética , Demência Vascular/genética , Polimorfismo Genético , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Aterosclerose/etiologia , Estudos Transversais , Análise Mutacional de DNA , Demência Vascular/complicações , Feminino , Humanos , Masculino
10.
Eura Medicophys ; 43(2): 241-54, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17589415

RESUMO

Topographical cortical organization of sensorimotor area has been shown to be highly plastic, altering his configuration in response to training in different tasks in healthy controls and neurological patients. The term ''brain plasticity'' encompasses all possible mechanisms of neuronal reorganization: recruitment of pathways that are functionally homologous to, but anatomically distinct from, the damaged ones (eg, non-pyramidal corticospinal pathways), synaptogenesis, dendritic arborisation and reinforcement of existing but functionally silent synaptic connections (particularly at the periphery of core lesion). The study of neuroplasticity has clearly shown the ability of the developing brain--and of the adult and ageing brain--to be shaped by environmental inputs both under normal conditions (ie, learning) and after a lesion. Neuronal aggregates adjacent, or distant to a lesion in the sensorimotor area can progressively adopt the function of the injured area. Imaging studies indicate that recovery of motor function after a lesion (i.e. stroke) is associated with a progressive change of activation patterns in specific brain structures. Transcranial magnetic stimulation (TMS) and magnetoencephalography (MEG) can detect reshaping of sensorimotor areas; they have a high temporal resolution but have several limitations. TMS can only provide bidimensional scalp maps and MEG depicts three-dimensional spatial characteristics of virtual neural generators obtained by use of a mathematical model of the head and brain. However, the use of objective methods that assess brain reactivity to a physical stimulus (i.e., TMS) or to a sensory input (ie, electrical stimulation to hand and fingers) can integrate information from self-paced motor tasks, because the resolution of abnormal activation over time could be secondary to recovery. Functional MRI (fMRI) and positron emission tomography (PET), on their own, have insufficient time resolution to follow the hierarchical activation of relays within a neural network; however, because of their excellent spatial resolution, they can integrate the findings of TMS and MEG. An integrated approach constitutes, at present, the best way to assess the brain plasticity both under normal conditions and after a lesion.


Assuntos
Atividade Motora/fisiologia , Plasticidade Neuronal/fisiologia , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Magnetoencefalografia , Tomografia por Emissão de Pósitrons , Estimulação Magnética Transcraniana
11.
Behav Neurol ; 2017: 7404289, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28912625

RESUMO

Cognitive dysfunction affects 40-65% of multiple sclerosis (MS) patients and can occur in the early stages of the disease. This study aimed to explore cognitive functions by means of the Italian version of the minimal assessment of cognitive function in MS (MACFIMS) in relapsing-remitting MS (RRMS) patients with very mild clinical disability to identify the primarily involved cognitive functions. Ninety-two consecutive RRMS patients with Expanded Disability Status Scale (EDSS) scores ≤ 2.5 and forty-two healthy controls (HC) were investigated. Our results show that 51.1% of MS patients have cognitive dysfunction compared to HC. An impairment of verbal and visual memory, working memory, and executive functions was found in the RRMS group. After subgrouping RRMS by EDSS, group 1 (EDSS ≤ 1.5) showed involvement of verbal memory and executive functions; moreover, group 2 (2 ≤ EDSS ≤ 2.5) patients were also impaired in information processing speed and visual memory. Our results show that utilizing a comprehensive neuropsychological assessment, approximately half of MS patients with very mild physical disability exhibit cognitive impairment with a primary involvement of prefrontal cognitive functions. Detecting impairment of executive functions at an early clinical stage of disease could be useful to promptly enroll MS patients in targeted rehabilitation.


Assuntos
Cognição/fisiologia , Disfunção Cognitiva/complicações , Função Executiva/fisiologia , Memória de Curto Prazo/fisiologia , Esclerose Múltipla Recidivante-Remitente/complicações , Adulto , Disfunção Cognitiva/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Esclerose Múltipla Recidivante-Remitente/psicologia , Testes Neuropsicológicos , Índice de Gravidade de Doença
12.
Stroke ; 33(3): 689-94, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11872889

RESUMO

BACKGROUND AND PURPOSE: Increases in the thickness of the intima and media of the carotid artery have been associated with an increased risk of myocardial infarction and stroke in subjects without a history of cardiovascular disease. Lacunar infarcts, one of the most common subtype of ischemic stroke, show unique pathological and clinicoradiological characteristics. The present study examines the relationship between vascular risk factors, including carotid artery intima-media thickness (IMT), and lacunar versus nonlacunar infarcts. METHODS: We collected data from patients with acute ischemic stroke admitted to hospital. Patients and 129 control subjects underwent B-mode ultrasonographic measurements of IMT of the common carotid artery. We examined the association of lacunar and nonlacunar infarcts with age, sex, and potential vascular risk factors. RESULTS: Of 292 adult patients with an acute first-ever ischemic stroke, 96 were considered lacunar and 196 were considered nonlacunar strokes. We did not find a significantly different percentage of diabetes, smoking, hypertension, dyslipidemia, myocardial infarction, and previous transient ischemic attack between the 2 groups of patients. The multinomial logistic regression procedure selected carotid artery IMT and atrial fibrillation as the only independent factors able to discriminate between lacunar and nonlacunar patients. IMT values were significantly higher in patients with nonlacunar stroke versus both those with lacunar stroke and control subjects. CONCLUSIONS: The present results indicate the usefulness of noninvasive measurement of IMT with ultrasonic techniques as a diagnostic tool that may help to identify different subtypes of ischemic stroke patients. The noninvasive measurements may have predictive power with respect to lacunar versus nonlacunar infarcts.


Assuntos
Infarto Encefálico/classificação , Infarto Encefálico/diagnóstico , Artéria Carótida Primitiva/diagnóstico por imagem , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , Doença Aguda , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Infarto Encefálico/epidemiologia , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco , Distribuição por Sexo , Ultrassonografia Doppler em Cores
13.
Stroke ; 32(7): 1552-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11441200

RESUMO

BACKGROUND AND PURPOSE: Evidence suggests that an alteration in cerebral hemodynamics plays a relevant role in the occurrence of stroke in patients with carotid occlusion. The purpose of the present study was to evaluate the relationships among baseline characteristics, type and number of collateral pathways, cerebral vasomotor reactivity (VMR), and outcome of patients with carotid occlusion. METHODS: One hundred four patients with symptomatic or asymptomatic internal carotid artery occlusion were followed up prospectively for a median period of 24 months. Cerebral VMR to apnea was calculated with transcranial Doppler ultrasonography by means of the breath-holding index (BHI) in the middle cerebral arteries. The patency of the 3 major intracranial collateral vessels was also evaluated. RESULTS: During the follow-up period, 18 patients experienced an ischemic stroke ipsilateral to internal carotid artery occlusion. Among factors considered, only older age, number of collateral pathways, and BHI values in the middle cerebral artery ipsilateral to the occluded side were significantly associated with the risk of ipsilateral stroke (P<0.001, P=0.008, and P<0.001, respectively; multiple Cox regression analysis). A normal VMR and favorable prognosis characterized patients with full collateral development; in this group, no patient experienced an ischemic event. On the other hand, an impaired VMR and increased probability of experiencing a stroke were found in patients without collateral pathways; the annual risk of ipsilateral stroke in this group was 32.7%. Patients with 1 or 2 collateral pathways showed a different VMR ranging from normal to strongly reduced BHI values. The ipsilateral stroke event risk was 17.5% in patients with 1 collateral vessel and 2.7% in patients with 2 collateral pathways. In this case, the risk of cerebrovascular events occurring during the follow-up period was significantly related to VMR. CONCLUSIONS: These data suggest that cerebral hemodynamic status in patients with carotid occlusive disease is influenced by both individual anatomic and functional characteristics. The planning of strategies to define the risk profile and any attempt to influence patients' outcome should be based on the evaluation of the intracranial hemodynamic adaptive status, with particular attention to the number of collateral vessels and the related VMR.


Assuntos
Isquemia Encefálica/etiologia , Estenose das Carótidas/complicações , Córtex Cerebral/irrigação sanguínea , Circulação Cerebrovascular , Acidente Vascular Cerebral/etiologia , Sistema Vasomotor , Idoso , Velocidade do Fluxo Sanguíneo , Isquemia Encefálica/mortalidade , Isquemia Encefálica/fisiopatologia , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/fisiopatologia , Circulação Colateral , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Estudos Prospectivos , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/fisiopatologia , Taxa de Sobrevida , Ultrassonografia Doppler Transcraniana
14.
Neurology ; 55(1): 35-40, 2000 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-10891901

RESUMO

OBJECTIVE: To investigate the correlation between changes in cerebral functional activity during mental engagement and the potential for neurologic recovery after stroke. BACKGROUND: Transcranial Doppler ultrasonography (TCD) makes it possible to detect the dynamic adjustment of cerebral perfusion related to functional neuronal changes. METHODS: TCD monitoring of flow velocity changes in the middle cerebral artery of 29 ischemic stroke patients was performed during an object recognition task. The study took place within 4 weeks from stroke onset. Based on recovery occurring after 2 months, the patients were divided into four groups depending on the side of hemispheric lesion and the presence or absence of neurologic recovery. Ten healthy subjects served as control subjects. RESULTS: During the recognition task, control subjects showed a bilateral increase in flow velocity with respect to the rest phase (right side, 7.02 +/- 1.3%; left side, 6.65 +/- 1. 1%), with no side-to-side difference. In patients who experienced recovery, a similar pattern of bilateral activation was observed, irrespective of the side of the lesion. Conversely, in patients with no recovery, the increase of flow velocity was significantly higher on the side contralateral to the brain lesion (p < 0.0001) with respect to the lesion side. Performance during the recognition task was comparable in the four groups of patients. CONCLUSIONS: These findings suggest that satisfactory recovery from a neurologic deficit requires the persistence of functional activity in the damaged hemisphere despite the presence of an anatomic lesion. The possibility of obtaining early prognostic indications with TCD may be relevant for an early selection of patients with the best probability of benefiting from rehabilitation therapy.


Assuntos
Córtex Cerebral/fisiopatologia , Circulação Cerebrovascular/fisiologia , Processos Mentais/fisiologia , Artéria Cerebral Média/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Idoso , Córtex Cerebral/diagnóstico por imagem , Lateralidade Funcional/fisiologia , Humanos , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Testes Neuropsicológicos , Valor Preditivo dos Testes , Prognóstico , Desempenho Psicomotor/fisiologia , Acidente Vascular Cerebral/psicologia , Ultrassonografia Doppler Transcraniana
15.
Neurology ; 59(8): 1153-61, 2002 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-12391342

RESUMO

OBJECTIVE: To determine whether serum trace metals and oxidative species are related to abnormal cognition in AD. METHODS: The authors studied serum peroxides, copper, iron, transferrin, and antioxidant capacity in 79 patients with AD (mean age 74.3 years; 25 men, 54 women) and in 76 cognitively normal individuals (mean age 70.1 years; 33 men, 43 women). The relation of these oxidative and trace metals to APOE epsilon4 allele frequency, neuropsychological performance, and cerebrovascular or atrophic burden, as estimated by brain MRI and ultrasonography of cerebral vessels, was evaluated. RESULTS: Copper level was higher (p < 0.001) in subjects with AD than control subjects (specificity = 95%, sensitivity = 60%) with a cutoff serum level of 16 micro mol/L (1.02 mg/L). An increase of 1 micro mol/L in serum copper accounted for 80% of the risk of having AD and correlated with poor neuropsychological performance and medial temporal lobe atrophy (p < 0.03). Antioxidant capacity decreased and correlated with medial temporal lobe atrophy (p < 0.009) and with APOE epsilon4 allele (p = 0.004). CONCLUSIONS: Copper may play a role in neurodegenerative processes in AD, and serum copper measurement may prove to be a peripheral diagnostic marker for AD.


Assuntos
Doença de Alzheimer/sangue , Cobre/sangue , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Análise de Variância , Biomarcadores/sangue , Distribuição de Qui-Quadrado , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Peróxidos/sangue , Estatísticas não Paramétricas , Ultrassonografia
16.
Neurology ; 57(1): 55-61, 2001 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-11445628

RESUMO

BACKGROUND: The motor impairment in Parkinson's disease (PD) could partly reflect a failure to activate processes of motor imagery. OBJECTIVE: To verify any selective changes of motor output during motor imagery, lateralized to the hemisphere contralateral to the clinically affected side of hemiparkinsonian patients. METHODS: Transcranial magnetic stimulation (TMS) was used to map the cortical representations of the contralateral abductor digiti minimi muscle (ADM) during rest, contraction, and motor imagery in a group of patients with hemi-PD and in a group of healthy volunteers. Seven patients with hemi-PD and seven healthy subjects were examined. Focal TMS was applied over a grid of 20 scalp positions on each hemiscalp. Maps were characterized by area (number of excitable positions), volume (the sum of motor evoked potential amplitudes at all scalp positions), and center of gravity (a map position representing an amplitude-weighted calculation of the excitable area). RESULTS: In healthy control subjects, the area of cortical representation of ADM was symmetrically increased in both hemispheres by mental simulation of movement and real muscle contraction. In patients with hemi-PD, there was a hemispheric asymmetry in the area of cortical representation elicited by motor imagery. The area was reduced in the clinically affected hemisphere. The volume of cortical representation was increased under all conditions and in both hemispheres in patients with PD. However, largely because the volume was so high at rest in patients, the increment in volume associated with contraction was smaller than in control subjects. CONCLUSION: This study demonstrates the presence of a tonic hyperactivation of motor cortical circuitry in PD in conjunction with an abnormality of either motor imagery or the process by which motor imagery engages the sensorimotor cortices in the clinically affected hemisphere.


Assuntos
Imaginação , Córtex Motor/fisiopatologia , Movimento , Doença de Parkinson/fisiopatologia , Mapeamento Encefálico , Limiar Diferencial , Dominância Cerebral , Eletromiografia , Potencial Evocado Motor , Feminino , Dedos/fisiopatologia , Humanos , Magnetismo , Masculino , Pessoa de Meia-Idade , Contração Muscular , Músculo Esquelético/fisiopatologia , Estimulação Física , Valores de Referência
17.
Brain Res ; 881(2): 159-64, 2000 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-11036154

RESUMO

In order to investigate the role of visceral afferent inputs flowing along autonomic fibers on corticospinal tract excitability, the variability of Motor Evoked Potentials (MEPs), elicited by Transcranial Magnetic Stimulation (TMS), was analysed during simultaneous monitoring of electrocardiogram (EKG) phases, breathing phases and sudomotor skin responses (SSRs) in a group of 10 healthy subjects. A cascade of at least 60 consecutive magnetic stimuli, with an interstimulus interval randomly varying between 20 and 40 s, was acquired. At the end of the recording session, the subject was asked to make at random five not consecutive self-paced forced inspirations. TMS was carried out at an intensity 10% above motor threshold excitability via a circular coil placed over the motor area of the right hemisphere. MEPs were recorded from the contralateral abductor digiti minimi muscle (ADM). Sudomotor Skin Responses (SSRs) were recorded on both hand palms. MEPs latency and amplitude did not show significant correlation with any of the EKG and respiratory phases. During forced inspiration, a significant latency shortening was found. TMS elicited SSRs, whose amplitudes were not correlated with MEP parameters. During forced inspiration a significant SSR amplitude increment, not correlated with MEP latency shortening, was also observed. These results assign a minor if any role to the considered autonomic parameters in modulating corticospinal motor excitability.


Assuntos
Vias Autônomas/fisiologia , Potencial Evocado Motor/fisiologia , Resposta Galvânica da Pele/fisiologia , Frequência Cardíaca/fisiologia , Tratos Piramidais/fisiologia , Respiração , Adulto , Análise de Variância , Intervalos de Confiança , Eletrocardiografia/métodos , Fenômenos Eletromagnéticos , Feminino , Humanos , Masculino
18.
J Neurol ; 246(12): 1172-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10653311

RESUMO

This study assessed the use of transcranial Doppler ultrasound in detecting selective changes in cerebral blood flow velocity during emotional processes. The role of the respective hemispheres in emotional processing is controversial. Cerebral control of emotional processing has previously been investigated by analysis of patients with unilateral brain damage, experiments with selective stimulation of only one hemisphere, and more recently by imaging techniques measuring local cerebral blood flow. We investigated mean flow velocity continuously and simultaneously in both the right and left middle cerebral arteries (MCAs) in 16 healthy right-handed young subjects at rest and during the performance of three tasks: task 1: 15 slides with nonemotional content; task 2: 15 slides with negative emotional content; task 3: 15 slides with nonemotional content with different content from that in task 1. The three tasks produced significantly different effects on the right and left hemispheres. During the two nonemotional tasks the increase in mean flow velocity over basal values was similar in the two MCAs (task 1: left MCA = 3.27 +/- 1.9%; right MCA = 3.63 +/- 2.1%; task 3: left MCA = 2.42 +/- 0.7%; right MCA = 2.56 +/- 1.3%); the negative emotional task was accompanied by a significantly higher increase in the right (11.31 +/- 1.6%) than in the left MCA (4.72 +/- 3.7%; analysis of variance two-way interaction: side of recording x task, F = 43.6, P < 0.001). These results show the possibility of obtaining specific functional information from bilateral transcranial Doppler ultrasound and suggest the involvement of the right hemisphere in emotional processing.


Assuntos
Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/fisiologia , Dominância Cerebral/fisiologia , Emoções/fisiologia , Ultrassonografia Doppler Transcraniana , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Mapeamento Encefálico , Feminino , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Humanos , Masculino
19.
J Neurol ; 248(2): 104-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11284126

RESUMO

Transcranial Doppler ultrasonography (TCD) has been widely used to obtain information about changes in cerebral perfusion during motor activity after stroke. This type of application is greatly limited when severe motor deficits are present that impede the performance of an active motor task. In this study, we explored the effect of performing passive arm movements on cerebral perfusion. Twenty healthy subjects were investigated. A bilateral TCD monitoring of the middle cerebral artery (MCA) flow velocity was performed during the following experimental conditions: 1-min of active and passive flexion-extension elbow movement and 1-min of active and passive dorsal extension hand movement. Each task was performed with both left and right arms. The percentage increase in flow velocity from rest to task performance was calculated. Each task produced a significantly greater increase in mean flow velocity in the contralateral MCA with respect to the ipsilateral. When comparing the effect of passive and active tasks, no significant difference in mean flow velocity changes recorded in the ipsilateral and the contralateral MCA was detected regarding either elbow or hand movements. These findings demonstrate the possibility of obtaining information about changes in hemispheric cerebral perfusion during passive movements involving elbow and hand. This type of application deserves further attention in the study of cerebral functional changes following cerebral lesions.


Assuntos
Circulação Cerebrovascular/fisiologia , Cotovelo/fisiologia , Mãos/fisiologia , Atividade Motora/fisiologia , Adulto , Análise de Variância , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Humanos , Masculino , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiologia , Valores de Referência , Ultrassonografia Doppler Transcraniana
20.
J Neurol ; 249(8): 993-1000, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12195443

RESUMO

This study evaluated the use of transcranial Doppler ultrasonography for detecting selective changes in cerebral blood flow velocity during emotional processes. The aim was to investigate the possibility of obtaining functional information on the neuropsychology of emotions in patients with Parkinson's disease (PD). For this reason, blood flow velocity changes were investigated in both middle cerebral arteries (MCA) during a rest condition and when viewing non emotional (tasks 1 and 3) and emotional (task 2) slide sequences. The study included 12 PD patients and 12 healthy subjects. All patients were in treatment with levodopa or dopamine agonist. Investigation of PD patients was performed during an on-phase. The three tasks produced significantly different effects on the right and left side in the PD patients compared with the control group. During the two non emotion-related tasks the increase of mean flow velocity (MFV) compared with the basal values was similar in the two middle cerebral arteries in both groups [(PD Patients: Task 1: left MCA = 3.95 % 2.2, Right MCA = 4.33 % +/- 2.3, Task 3: left MCA = 3.04 % +/- 1.9, Right MCA = 2.71 % +/- 2.2) (control group: Task 1: left MCA = 4.57 % +/- 1.4, Right MCA = 4.46 % +/- 1.7, Task 3: left MCA = 2.32 % +/- 0.9, Right MCA = 2.52 % +/- 1.2)] The negative emotional task was accompanied by a significantly higher increase in the right (10.53 % +/- 3.2) than in the left middle cerebral artery (4.52 % +/- 1.51) only in the control group. The PD patients showed a bilateral and symmetrical increase of MFV (left MCA = 4.28 % +/- 2.3 and right MCA 5.77 % +/-3.8). To determine whether there was a dysfunction in cerebrovascular reactivity and a deficit in the ability to activate both hemispheres in response to non emotion-related stimuli in the PD patients, the protocol study included a cerebrovascular reactivity test to apnea, a motor task (thumb-to-finger opposition), a cognitive task (word fluency and visual discrimination of objects), performed by both patients and controls. The pattern of MFV changes during these tasks was not statistically significantly different in the two experimental groups. In order to evaluate the possible influence of drug treatment on cerebrovascular reactivity, seven patients were also evaluated during an off-phase, after a 48-hour wash-out period. Changes in MFV during every task were similar to that observed during the on-phase. These findings show the possibility of obtaining specific functional information from bilateral transcranial Doppler and suggest the selective and specific deficit of PD patients in emotional processing.


Assuntos
Encéfalo/irrigação sanguínea , Doença de Parkinson/fisiopatologia , Ultrassonografia Doppler Transcraniana , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Emoções/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/fisiopatologia , Testes Neuropsicológicos , Doença de Parkinson/psicologia
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