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1.
Comput Methods Biomech Biomed Engin ; 26(4): 450-459, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35472257

RESUMO

When assessing a patient with knee osteoarthritis (OA), a number of factors are considered to guide treatment plan, namely, demographic, radiographic, clinical, musculoskeletal, and biomechanical factors. The aim of this study is to identify which of these factors are the most related to each other to potentially better prioritize the modifiable factors to be addressed as they may influence treatment outcomes. We investigated a multimodal canonical correlation analysis to evaluate associations between these factors. The analysis was performed on 415 OA patients who were not candidates for knee arthroplasty, to identify factors that are associated to the patients' clinical conditions.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/terapia , Osteoartrite do Joelho/cirurgia , Resultado do Tratamento , Tomada de Decisões
3.
Eur J Neurol ; 25(5): 787-789, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29427459

RESUMO

BACKGROUND AND PURPOSE: Acute onset of amnestic syndrome may represent a challenging diagnostic issue. In addition to non-vascular etiology, thalamic strokes or infarction involving several temporal lobe structures have been reported. METHODS: We describe three patients in whom an isolated bilateral anterior fornix infarction presented with an acute amnestic syndrome. Clinical presentation, differential diagnosis and magnetic resonance images are discussed for each patient and vascular anatomy of the involved brain regions is also considered. RESULTS: Bilateral anterior columns of the fornix showed cytotoxic edema and bilateral narrowing of anterior cerebral artery was demonstrated. CONCLUSIONS: We suggest that bilateral fornix infarction should always be considered in the diagnostic work-up of an amnestic syndrome with acute onset.


Assuntos
Amnésia/etiologia , Infarto Cerebral/complicações , Fórnice/patologia , Acidente Vascular Cerebral/complicações , Idoso , Amnésia/diagnóstico por imagem , Amnésia/patologia , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/patologia , Feminino , Fórnice/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia
4.
Neurol Sci ; 38(1): 83-91, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27624723

RESUMO

Dementia with Lewy bodies (DLB) causes elevated outlays for the National Health Systems due to high institutionalization rate and patients' reduced quality of life and high mortality. Furthermore, DLB is often misdiagnosed as Alzheimer's disease. These data motivate harmonized multicenter longitudinal cohort studies to improve clinical management and therapy monitoring. The Italian DLB study group of the Italian Neurological Society for dementia (SINdem) developed and emailed a semi-structured questionnaire to 572 national dementia centers (from primary to tertiary) to prepare an Italian large longitudinal cohort. The questionnaire surveyed: (1) prevalence and incidence of DLB; (2) clinical assessment; (3) relevance and availability of diagnostic tools; (4) pharmacological management of cognitive, motor, and behavioural disturbances; (5) causes of hospitalization, with specific focus on delirium and its treatment. Overall, 135 centers (23.6 %) contributed to the survey. Overall, 5624 patients with DLB are currently followed by the 135 centers in a year (2042 of them are new patients). The percentage of DLB patients was lower (27 ± 8 %) than that of Alzheimer's disease and frontotemporal dementia (56 ± 27 %) patients. The majority of the centers (91 %) considered the clinical and neuropsychological assessments as the most relevant procedure for a DLB diagnosis. Nonetheless, most of the centers has availability of magnetic resonance imaging (MRI; 95 %), electroencephalography (EEG; 93 %), and FP-CIT single photon emission-computerized tomography (SPECT; 75 %) scan for clinical applications. It will be, therefore, possible to recruit a large harmonized Italian cohort of DLB patients for future cross-sectional and longitudinal multicenter studies.


Assuntos
Doença por Corpos de Lewy/diagnóstico , Doença por Corpos de Lewy/terapia , Doença de Alzheimer/diagnóstico , Estudos de Coortes , Diagnóstico Diferencial , Gerenciamento Clínico , Humanos , Itália , Projetos de Pesquisa , Inquéritos e Questionários
5.
Eur J Neurol ; 23(8): 1322-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27132982

RESUMO

BACKGROUND AND PURPOSE: Transcranial sonography (TCS) of the brain parenchyma is used to visualize alterations in the substantia nigra (SN) and it is applied for early diagnosis of Parkinson's disease. Our aim was to explore specific echogenic alterations of the SN in dementia with Lewy bodies (DLB) compared to Alzheimer's disease (AD). METHODS: Seventy-one subjects underwent TCS: 22 DLB, 28 AD and 21 healthy elderly controls. Cognitive impairment, extrapyramidal signs, visual hallucinations, fluctuations and rapid eye movement sleep behaviour symptoms were investigated. TCS assessed SN hyperechogenicity and symmetry. RESULTS: Transcranial sonography revealed SN hyperechogenicity in 100% of DLB compared to 50% of AD and 30% of controls. Mean SN echogenic area (cm(2) ) was 0.22 ± 0.03 in DLB, 0.15 ± 0.03 in AD and 0.14 ± 0.03 in controls (P < 0.0001). More than 50% of DLB presented a marked hyperechogenicity (cutoff value >0.22 cm(2) ) compared to only 10% of AD (P < 0.0003). DLB had symmetrical SN enlargement, whereas AD were mostly asymmetrical (P = 0.015). A combination of SN echogenic area and asymmetry index had a sensitivity of 88.9% and a specificity of 81.2% in discriminating DLB from AD (positive predictive value 85.7%, negative predictive value 85.7%). No association was found between SN hyperechogenicity and Unified Parkinson's Disease Rating Scale part III, Mini Mental State Examination or the presence of visual hallucinations. CONCLUSIONS: Transcranial sonography may be a valid supportive tool in the diagnostic workup of neurodegenerative dementia helping clinicians to distinguish DLB from AD even at the early stages.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença por Corpos de Lewy/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Sensibilidade e Especificidade , Ultrassonografia Doppler Transcraniana
6.
Am J Alzheimers Dis Other Demen ; 30(6): 635-44, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25792664

RESUMO

Although the Anosognosia Questionnaire-Dementia (AQ-D) is one of the main instruments for assessing awareness in Alzheimer's disease (AD), the normative data were until now limited to people from Argentina and Japan. This study aims to validate this instrument in an European context, in particular in an Italian sample. In a multicenter project (Verona, Padova, and Trapani), 130 patients with AD and their caregivers participated in the study. Psychometric characteristics of AQ-D are confirmed indicating that the scale permits the early identification of anosognosia and the correct care management of patients. Indeed, anosognosia results to be present also in patients with very mild AD (moderate: 44.44%; mild: 47.17%; and very mild: 23.73%). Moreover, the results indicate that deficits in awareness may vary in severity and that different types of anosognosia may be identified.


Assuntos
Agnosia/diagnóstico , Doença de Alzheimer/diagnóstico , Escalas de Graduação Psiquiátrica/normas , Psicometria/métodos , Idoso , Idoso de 80 Anos ou mais , Agnosia/etiologia , Doença de Alzheimer/complicações , Feminino , Humanos , Itália , Masculino , Psicometria/instrumentação , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
7.
Neurology ; 77(21): 1873-6, 2011 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22076548

RESUMO

OBJECTIVE: To explore the efficacy of spinal MRI study with subtraction analysis as a rapid, reliable, and noninvasive procedure to detect epidural CSF collection in spontaneous intracranial hypotension (SIH) syndrome. METHODS: Seventeen patients (mean age 42 years, age range 17-65 years; 11 female) with SIH diagnosed using the International Classification of Headache Disorders criteria and 13 age-matched control subjects underwent standard sagittal spinal MRI. Postprocessing image analysis with subtraction of T1-weighted from T2-weighted MRI scans was performed and tested for the detection of the CSF leak. RESULTS: The CSF epidural collection was visible in all patients with SIH and was detected at the dorsal (16 of 17), cervical (13 of 17), lumbar (13 of 17), and sacral (12 of 17) levels. None of the control subjects showed a CSF leak. Diverticula were present in 23% of patients, whereas the actual site of the CSF leak was recognized in only one patient. Eight patients were treated conservatively, whereas 9 patients required an epidural blood patch, performed at a fixed L2-L3 or L3-L4 spinal level, with complete recovery. CONCLUSIONS: Spinal MRI with dedicated subtraction analysis could represent the first-line diagnostic tool in the management of patients with SIH, thus leaving invasive investigation for selected patients, such those requiring dural surgery.


Assuntos
Rinorreia de Líquido Cefalorraquidiano/diagnóstico , Rinorreia de Líquido Cefalorraquidiano/etiologia , Hipotensão Intracraniana/complicações , Imageamento por Ressonância Magnética , Adolescente , Adulto , Idoso , Espaço Epidural/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mielografia/métodos , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Adulto Jovem
8.
J Neurooncol ; 99(2): 287-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20146085

RESUMO

Thymoma-associated paraneoplastic diseases include myasthenia gravis (MG), neuromyotonia (NMT), Morvan's syndrome, and several non-neurological paraneoplastic manifestations, including glomerulonephritis. Paraneoplastic syndromes often precede the occurrence of thymoma, but cases occurring after thymomectomy, which sometimes herald the recurrence of thymoma, have also been described. We report on a patient who developed MG after thymomectomy for a malignant thymoma. After MG remission, NMT and Morvan's syndrome occurred, which heralded a mediastinic recurrence, as demonstrated only by autopsy findings.


Assuntos
Síndrome de Isaacs/etiologia , Miastenia Gravis/etiologia , Síndromes Paraneoplásicas/etiologia , Siringomielia/etiologia , Timectomia/efeitos adversos , Timoma/cirurgia , Neoplasias do Timo/cirurgia , Adulto , Evolução Fatal , Humanos , Síndrome de Isaacs/tratamento farmacológico , Masculino , Miastenia Gravis/tratamento farmacológico , Síndromes Paraneoplásicas/tratamento farmacológico , Prognóstico , Siringomielia/tratamento farmacológico
9.
BMJ Case Rep ; 2008: bcr0620080283, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-21716820

RESUMO

Wegener's granulomatosis (WG) is a multisystemic necrotising granulomatous vasculitis of small and medium sized vessels, that primarily involves the upper and lower respiratory tracts, lung tissues and kidneys. Serum antineutrophil cytoplasmic antibodies (ANCA) are a sensitive and specific marker of WG. Whereas the peripheral nervous system is often involved in WG, central nervous system manifestations are reported only in 2-8%, and are rarely present at onset. We report on a patient with atypical neurological presentation of ANCA negative WG in whom the diagnosis was made only after a meningeal biopsy.


Assuntos
Encéfalo/patologia , Doenças do Sistema Nervoso Central/diagnóstico , Doenças do Sistema Nervoso Central/etiologia , Granulomatose com Poliangiite/diagnóstico , Idoso , Anticorpos Anticitoplasma de Neutrófilos/sangue , Biópsia , Doenças do Sistema Nervoso Central/complicações , Transtornos de Deglutição/etiologia , Disfonia/etiologia , Feminino , Granulomatose com Poliangiite/complicações , Granulomatose com Poliangiite/tratamento farmacológico , Humanos
10.
J Neural Transm Suppl ; (72): 175-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17982892

RESUMO

Alterations in cholesterol homeostasis are associated with Alzheimer's disease (AD). The role played by specific fractions of serum lipoproteins in modifying the risk of AD, and the interaction with APOE genotype has not yet been investigated. We studied serum lipoprotein profiles using a gradient-density ultracentrifugation method in a cohort of late-onset sporadic AD patients without cerebrovascular lesions and in healthy elderly subjects. In the AD group the lipoprotein cholesterol distribution showed an increase in LDL cholesterol, reaching a significant difference with respect to controls in the LDL sub-fractions representing the transition between small dense-LDL (fraction 11, p = 0.04) and normal-density LDL particles (fraction 12, p = 0.03). APOE genotype and LDL cholesterol were independently associated with AD. The mean concentration of LDL in fractions 11 and 12 increased the risk of developing AD (p = 0.01 and p = 0.025, respectively). These results confirm that an alteration of cholesterol homeostasis is associated with AD and that serum concentrations of LDL cholesterol are higher in AD patients without cerebrovascular pathology than in elderly normal subjects. The presence of the APOE epsilon4+ allele is a risk factor for AD independent of increased serum cholesterol or a modification of other vascular risk factors. Increased levels of specific sub-fractions of LDL cholesterol may be associated with increased risk of AD.


Assuntos
Doença de Alzheimer/genética , Apolipoproteínas E/genética , LDL-Colesterol/sangue , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/sangue , Apolipoproteína E4/genética , Centrifugação com Gradiente de Concentração , Colesterol/sangue , Estudos de Coortes , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Triglicerídeos/sangue
12.
Acta Neurol Scand Suppl ; 185: 107-14, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16866919

RESUMO

Evidence from numerous neuropathological observations and in vivo clinical imaging studies suggests a prominent role of activated microglia, the main effector cell of the brain's innate immune system, in Alzheimer's disease and other neurodegenerative diseases. Though the comprehensive molecular definition of the microglial activation process is still incomplete, the de novo expression of 'peripheral benzodiazepine-binding sites (PBBS)' by activated but not resting microglia has been established as a useful descriptor of functional state changes in microglia. As microglial transformation to an activated state is closely linked to progressive changes in brain disease, the detection of activated microglia can provide information about disease distribution and rate of disease progression. Positron emission tomography (PET) and [(11)C](R)-PK11195, a specific ligand of the PBBS, have been used to study systematically microglial activation in vivo. Significant microglial activation is present in the brains of patients with neurodegenerative dementia even at early and possibly preclinical stages of the disease with a spatial distribution reflecting different clinical phenotypes. We review some of the posited functions of activated microglia in the pathophysiology of dementia and speculate on the relationship between increased regional [(11)C](R)-PK11195 signals and the ensuing changes in brain volume. Finally, we provide a brief outlook on the development of new radioligands for the PBBS.


Assuntos
Demência/etiologia , Microglia/fisiologia , Doenças Neurodegenerativas/etiologia , Benzodiazepinas/metabolismo , Sítios de Ligação , Encéfalo/metabolismo , Encéfalo/patologia , Demência/patologia , Humanos , Doenças Neurodegenerativas/patologia
13.
Gut ; 55(4): 547-53, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16210399

RESUMO

BACKGROUND AND AIMS: One proposed mechanism whereby hepatic encephalopathy (HE) leads to loss of brain function is dysregulated synthesis of neurosteroids. Mitochondrial synthesis of neurosteroids is regulated by "peripheral benzodiazepine binding sites" (PBBS). Expressed in the brain by activated glial cells, PBBS can be measured in vivo by the specific ligand [11C](R)-PK11195 and positron emission tomography (PET). Recently, it has been suggested that PBBS expressing glial cells may play a role in the general inflammatory responses seen in HE. Therefore, we measured PBBS in vivo in the brains of patients with minimal HE using [11C](R)-PK11195 PET. METHODS: Five patients with minimal HE and biopsy proven cirrhosis of differing aetiology were assessed with a neuropsychometric battery. Regional expression of PBBS in the brain was detected by [11C](R)-PK11195 PET. RESULTS: All patients showed brain regions with increased [11C](R)-PK11195 binding. Significant increases in glial [11C](R)-PK11195 binding were found bilaterally in the pallidum, right putamen, and right dorsolateral prefrontal region. The patient with the most severe cognitive impairment had the highest increases in regional [11C](R)-PK11195 binding. CONCLUSION: HE is associated with increased cerebral binding of [11C](R)-PK11195 in vivo, reflecting increased expression of PBBS by glial cells. This supports earlier experimental evidence in rodent models of liver failure, suggesting that an altered glial cell state, as evidenced by the increase in cerebral PBBS, might be causally related to impaired brain functioning in HE.


Assuntos
Benzodiazepinas/metabolismo , Encéfalo/metabolismo , Encefalopatia Hepática/metabolismo , Idoso , Sítios de Ligação , Estudos de Coortes , Feminino , Encefalopatia Hepática/psicologia , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/psicologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Psicometria/métodos
14.
Eur J Neurol ; 11(10): 709-10, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15469457

RESUMO

Thiethylperazine (Torecan) is a piperazine phenothiazine employed to relieve vertigo. Its use may be associated with extrapyramidal side effects (dystonia, akathisia, tardive dyskinesia) (Sulkava, 1984), but parkinsonism has rarely been described. We describe a woman who, 1 month after the onset of thiethylperazine treatment, developed parkinsonism that disappeared 2 months after withdrawal of the drug. However, cerebral single-photon emission computed tomography (SPECT) with the dopamine (DA) D2 receptors ligand 123I-iodobenzamide (123I-IBZM) revealed a persistent reduced DA D2 receptors activity (by 45%) in the basal ganglia (BG), which may be clinically not effective.


Assuntos
Benzamidas/farmacologia , Antagonistas dos Receptores de Dopamina D2 , Transtornos Parkinsonianos/diagnóstico por imagem , Pirrolidinas/farmacologia , Gânglios da Base/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Humanos , Isótopos de Iodo , Pessoa de Meia-Idade , Transtornos Parkinsonianos/induzido quimicamente , Tietilperazina , Tomografia Computadorizada de Emissão de Fóton Único/métodos
15.
Neurobiol Dis ; 15(3): 601-9, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15056468

RESUMO

Microglial activation is implicated in the pathogenesis of ALS and can be detected in animal models of the disease that demonstrate increased survival when treated with anti-inflammatory drugs. PK11195 is a ligand for the "peripheral benzodiazepine binding site" expressed by activated microglia. Ten ALS patients and 14 healthy controls underwent [(11)C](R)-PK11195 PET of the brain. Volumes of interest were defined to obtain [(11)C](R)-PK11195 regional binding potential values for motor and "extra-motor" regions. Significantly increased binding was found in motor cortex (P = 0.003), pons (P = 0.004), dorsolateral prefrontal cortex (P = 0.010) and thalamus (P = 0.005) in the ALS patients, with significant correlation between binding in the motor cortex and the burden of upper motor neuron signs clinically (r = 0.73, P = 0.009). These findings indicate that cerebral microglial activation can be detected in vivo during the evolution of ALS, and support the previous observations that cerebral pathology is widespread. They also argue for the development of therapeutic strategies aimed at inflammatory pathways.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Microglia/metabolismo , Adulto , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Feminino , Humanos , Isoquinolinas/metabolismo , Masculino , Microglia/patologia , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão
16.
Neurology ; 61(5): 686-9, 2003 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-12963764

RESUMO

Microglia, the brain's intrinsic macrophages, bind (R)-PK11195 when activated by neuronal injury. The authors used [11C](R)-PK11195 PET to localize in vivo microglial activation in patients with multiple system atrophy (MSA). Increased [11C](R)-PK11195 binding was primarily found in the dorsolateral prefrontal cortex, putamen, pallidum, pons, and substantia nigra, reflecting the known distribution of neuropathologic changes in MSA. Providing an indicator of disease activity, [11C](R)-PK11195 PET can thus be used to characterize the in vivo neuropathology of MSA.


Assuntos
Isoquinolinas , Microglia/diagnóstico por imagem , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Idoso , Radioisótopos de Carbono , Humanos , Masculino , Pessoa de Meia-Idade
18.
J Neural Transm (Vienna) ; 109(3): 393-8, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11956959

RESUMO

Neuropathological hallmarks of Alzheimer's disease (AD) are amyloid plaques and neurofibrillary tangles, containing betaA(42) peptide and tau protein, respectively. Amyloid plaques contain also glycosaminoglycans (GAGs). Whereas cerebrospinal fluid (CSF) levels of betaA(42) peptide and tau protein have been demonstrated as potential markers of Alzheimer's disease (AD), no data are available for GAGs. We determined (Elisa) tau and betaA(42) CSF levels, as well as serum antibodies to GAGs in 9 AD patients, and the values were analyzed in relation to age and severity of the disease. Beta-A42 and tau CSF levels were significantly reduced and increased, respectively, in AD patients when compared to controls, but they did not correlate with the severity of the disease. Despite their role in amyloidogenesis, we did not find evidence for the use of GAGs as diagnostic marker of AD.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Anticorpos/sangue , Encéfalo/metabolismo , Glicosaminoglicanos/imunologia , Fragmentos de Peptídeos/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Idoso , Doença de Alzheimer/patologia , Encéfalo/imunologia , Progressão da Doença , Glicosaminoglicanos/metabolismo , Humanos , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/metabolismo , Emaranhados Neurofibrilares/patologia , Placa Amiloide/metabolismo , Placa Amiloide/patologia
19.
Neuroreport ; 12(16): 3439-42, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11733686

RESUMO

Limb denervation leads to reorganization of the representational zones of the somatosensory cortex. Using [11C](R)-PK11195, a sensitive in vivo marker of glial cell activation, and PET, we provide first evidence that limb denervation induces a trans-synaptic increase in [11C](R)-PK11195 binding in the human thalamus but not somatosensory cortex: these brain structures appeared morphologically normal on magnetic resonance imaging (MRI). The increased thalamic signal was detectable many years after nerve injury, indicating persistent reorganization of the thalamus. This glial activation, beyond the first-order projection area of the injured neurons, may reflect continually altered afferent activity. Our findings support the view that long-term rearrangement of cortical representational maps is significantly determined within the thalamus.


Assuntos
Neuroglia/fisiologia , Traumatismos dos Nervos Periféricos , Sinapses/fisiologia , Tálamo/fisiopatologia , Adulto , Amputação Traumática/metabolismo , Amputação Traumática/fisiopatologia , Sítios de Ligação , Feminino , Humanos , Isoquinolinas/metabolismo , Masculino , Pessoa de Meia-Idade , Neuroglia/metabolismo , Plasticidade Neuronal/fisiologia , Nervos Periféricos/metabolismo , Receptores de GABA-A/análise , Sinapses/metabolismo , Tálamo/metabolismo , Fatores de Tempo , Tomografia Computadorizada de Emissão/métodos
20.
Brain ; 124(Pt 10): 2014-27, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11571219

RESUMO

A major challenge in the assessment of brain injury and its relationship to the ensuing functional deficits is the accurate delineation of the areas of damage. Here, we test the hypothesis that the anatomical distribution pattern of activated microglia, a normally dormant population of resident brain macrophages, can be used as a surrogate marker of neuronal injury not only at the primary lesion site but also in the antero- and retrograde projection areas of the lesioned neurones. Two patients with asymmetrical herpes simplex encephalitis were serially scanned 6 and 12 months after the acute illness using PET with [11C] (R)-PK11195, a marker of activated microglia/brain macrophages. The evolving structural changes in the brain were measured by volumetric MRI and compared with the pattern of [11C](R)-PK11195 binding. Corresponding to the clinically observed cognitive deficits, quantitative [11C](R)-PK11195-PET revealed highly significant signal increases within the affected limbic system and additionally in areas connected to the limbic system by neural pathways, including the lingual gyrus in the occipital lobe and the inferior parietal lobe, which had normal morphology on structural MRI. The increased [11C](R)-PK11195 binding, signifying the presence of activated microglia, persisted many months (>12) after antiviral treatment. Cortical areas that showed early high [11C](R)-PK11195 binding subsequently underwent atrophy. These observations demonstrate that in vivo imaging of activated microglia/brain macrophages provides a dynamic measure of active tissue changes following an acute focal lesion. Importantly, the glial tissue response in the wake of neuronal damage is protracted and widespread within the confines of the affected distributed neural system and can be related to the long-term functional deficits.


Assuntos
Encefalite por Herpes Simples/metabolismo , Isoquinolinas/metabolismo , Neuroglia/metabolismo , Neurônios/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sítios de Ligação , Encéfalo/metabolismo , Encéfalo/patologia , Radioisótopos de Carbono , Distribuição de Qui-Quadrado , Análise por Conglomerados , Encefalite por Herpes Simples/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroglia/patologia , Neurônios/metabolismo , Análise de Regressão , Tomografia Computadorizada de Emissão
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