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1.
N Engl J Med ; 384(18): 1691-1704, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33720637

RESUMO

BACKGROUND: A hallmark of Alzheimer's disease is the accumulation of amyloid-ß (Aß) peptide. Donanemab, an antibody that targets a modified form of deposited Aß, is being investigated for the treatment of early Alzheimer's disease. METHODS: We conducted a phase 2 trial of donanemab in patients with early symptomatic Alzheimer's disease who had tau and amyloid deposition on positron-emission tomography (PET). Patients were randomly assigned in a 1:1 ratio to receive donanemab (700 mg for the first three doses and 1400 mg thereafter) or placebo intravenously every 4 weeks for up to 72 weeks. The primary outcome was the change from baseline in the score on the Integrated Alzheimer's Disease Rating Scale (iADRS; range, 0 to 144, with lower scores indicating greater cognitive and functional impairment) at 76 weeks. Secondary outcomes included the change in scores on the Clinical Dementia Rating Scale-Sum of Boxes (CDR-SB), the 13-item cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-Cog13), the Alzheimer's Disease Cooperative Study-Instrumental Activities of Daily Living Inventory (ADCS-iADL), and the Mini-Mental State Examination (MMSE), as well as the change in the amyloid and tau burden on PET. RESULTS: A total of 257 patients were enrolled; 131 were assigned to receive donanemab and 126 to receive placebo. The baseline iADRS score was 106 in both groups. The change from baseline in the iADRS score at 76 weeks was -6.86 with donanemab and -10.06 with placebo (difference, 3.20; 95% confidence interval, 0.12 to 6.27; P = 0.04). The results for most secondary outcomes showed no substantial difference. At 76 weeks, the reductions in the amyloid plaque level and the global tau load were 85.06 centiloids and 0.01 greater, respectively, with donanemab than with placebo. Amyloid-related cerebral edema or effusions (mostly asymptomatic) occurred with donanemab. CONCLUSIONS: In patients with early Alzheimer's disease, donanemab resulted in a better composite score for cognition and for the ability to perform activities of daily living than placebo at 76 weeks, although results for secondary outcomes were mixed. Longer and larger trials are necessary to study the efficacy and safety of donanemab in Alzheimer's disease. (Funded by Eli Lilly; TRAILBLAZER-ALZ ClinicalTrials.gov number, NCT03367403.).


Assuntos
Doença de Alzheimer/tratamento farmacológico , Placa Amiloide/tratamento farmacológico , Atividades Cotidianas , Administração Intravenosa , Idoso , Edema Encefálico/induzido quimicamente , Cognição/efeitos dos fármacos , Progressão da Doença , Método Duplo-Cego , Epitopos , Feminino , Humanos , Masculino , Testes de Estado Mental e Demência , Ácido Pirrolidonocarboxílico/antagonistas & inibidores , Índice de Gravidade de Doença
2.
Alzheimers Dement ; 20(3): 2240-2261, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38170841

RESUMO

INTRODUCTION: The pace of innovation has accelerated in virtually every area of tau research in just the past few years. METHODS: In February 2022, leading international tau experts convened to share selected highlights of this work during Tau 2022, the second international tau conference co-organized and co-sponsored by the Alzheimer's Association, CurePSP, and the Rainwater Charitable Foundation. RESULTS: Representing academia, industry, and the philanthropic sector, presenters joined more than 1700 registered attendees from 59 countries, spanning six continents, to share recent advances and exciting new directions in tau research. DISCUSSION: The virtual meeting provided an opportunity to foster cross-sector collaboration and partnerships as well as a forum for updating colleagues on research-advancing tools and programs that are steadily moving the field forward.


Assuntos
Doença de Alzheimer , Tauopatias , Humanos , Proteínas tau
3.
Mov Disord ; 37(3): 513-524, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34859493

RESUMO

BACKGROUND: Mevidalen is a selective positive allosteric modulator (PAM) of the dopamine D1 receptor subtype. OBJECTIVE: To assess the safety and efficacy of mevidalen for treatment of cognition in patients with Lewy body dementia (LBD). METHODS: PRESENCE was a phase 2, 12-week study in participants with LBD (N = 344) randomly assigned (1:1:1:1) to daily doses of mevidalen (10, 30, or 75 mg) or placebo. The primary outcome measure was change from baseline on Cognitive Drug Research Continuity of Attention (CoA) composite score. Secondary outcomes included Alzheimer's Disease Assessment Scale-Cognitive Subscale 13 (ADAS-cog13 ), Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS), and Alzheimer's Disease Cooperative Study-Clinical Global Impression of Change (ADCS-CGIC). Numerous safety measures were collected. RESULTS: Mevidalen failed to meet primary or secondary cognition endpoints. Mevidalen resulted in significant, dose-dependent improvements of MDS-UPDRS total score (sum of Parts I-III, 10 mg P < 0.05, 30 mg P < 0.05, 75 mg P < 0.01, compared to placebo). The 30 mg and 75 mg mevidalen doses significantly improved ADCS-CGIC scores compared to placebo (minimal or better improvement: 30 mg P < 0.01, 75 mg P < 0.01; moderate or better improvement: 30 mg P < 0.05, 75 mg P < 0.001). Increases in blood pressure, adverse events, and cardiovascular serious adverse events were most pronounced at the 75 mg dose. CONCLUSIONS: Mevidalen harnesses a novel mechanism of action that improves motor symptoms associated with LBD on top of standard of care while improving or not worsening non-motor symptoms associated with traditional dopaminergic therapy. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença de Alzheimer , Doença por Corpos de Lewy , Fármacos Neuroprotetores , Cognição , Método Duplo-Cego , Humanos , Doença por Corpos de Lewy/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico
4.
BMC Neurol ; 21(1): 459, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34814867

RESUMO

BACKGROUND: Dopamine transporter single-photon emission computed tomography (DaT-SPECT) can quantify the functional integrity of the dopaminergic nerve terminals and has been suggested as an imaging modality to verify the clinical diagnosis of Parkinson's disease (PD). Depending on the stage of progression, approximately 5-15% of participants clinically diagnosed with idiopathic PD have been observed in previous studies to have normal DaT-SPECT patterns. However, the utility of DaT-SPECT in enhancing early PD participant selection in a global, multicenter clinical trial of a potentially disease-modifying therapy is not well understood. METHODS: The SPARK clinical trial was a phase 2 trial of cinpanemab, a monoclonal antibody against alpha-synuclein, in participants with early PD. DaT-SPECT was performed at screening to select participants with DaT-SPECT patterns consistent with degenerative parkinsonism. Acquisition was harmonised across 82 sites. Images were reconstructed and qualitatively read at a central laboratory by blinded neuroradiologists for inclusion prior to automated quantitative analysis. RESULTS: In total, 482 unique participants were screened between January 2018 and May 2019; 3.8% (15/398) of imaged participants were excluded owing to negative DaT-SPECT findings (i.e., scans without evidence of dopaminergic deficit [SWEDD]). CONCLUSION: A smaller proportion of SPARK participants were excluded owing to SWEDD status upon DaT-SPECT screening than has been reported in prior studies. Further research is needed to understand the reasons for the low SWEDD rate in this study and whether these results are generalisable to future studies. If supported, the radiation risks, imaging costs, and operational burden of DaT-SPECT for enrichment may be mitigated by clinical assessment and other study design aspects. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03318523 . Date submitted: October 19, 2017. First Posted: October 24, 2017.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina , Doença de Parkinson , Biomarcadores , Dopamina , Humanos , Doença de Parkinson/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único
5.
Mov Disord ; 34(8): 1154-1163, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31211448

RESUMO

BACKGROUND: Pathological and genetic evidence implicates toxic effects of aggregated α-synuclein in the pathophysiology of neuronal dysfunction and degeneration in Parkinson's disease. Immunotherapy targeting aggregated α-synuclein is a promising strategy for delaying disease progression. OBJECTIVE: This study (NCT02459886) evaluated the safety, tolerability, and pharmacokinetics of BIIB054, a human-derived monoclonal antibody that preferentially binds to aggregated α-synuclein, in healthy volunteers and participants with Parkinson's disease. METHODS: A total of 48 healthy volunteers (age 40-65, 19 women) and 18 Parkinson's disease participants (age 47-75, 5 women, Hoehn and Yahr stage ≤2.5) were in the study. Volunteers were enrolled into 6 single-dose cohorts of BIIB054 (range 1-135 mg/kg) or placebo, administered intravenously; Parkinson's disease participants received a single dose of BIIB054 (15 or 45 mg/kg) or placebo. All participants were evaluated for 16 weeks with clinical, neuroimaging, electrocardiogram, and laboratory assessments. Serum and cerebrospinal fluid BIIB054 concentrations were measured. BIIB054/α-synuclein complexes were measured in plasma. RESULTS: Most adverse events were mild and assessed by investigators as unrelated to the study drug. Pharmacokinetic parameters for volunteers and the Parkinson's disease participants were similar. BIIB054 serum exposure and maximum concentrations were dose proportional during the dose range studied. In volunteers and the Parkinson's disease participants, the serum half-life of BIIB054 was 28 to 35 days; the cerebrospinal fluid-to-serum ratio ranged from 0.13% to 0.56%. The presence of BIIB054/α-synuclein complexes in plasma was confirmed; all Parkinson's disease participants showed almost complete saturation of the BIIB054/α-synuclein complex formation. CONCLUSIONS: BIIB054 has favorable safety, tolerability, and pharmacokinetic profiles in volunteers and Parkinson's disease participants, supporting further clinical development. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Fatores Imunológicos/uso terapêutico , Doença de Parkinson/tratamento farmacológico , alfa-Sinucleína/imunologia , Adulto , Idoso , Anticorpos Monoclonais/farmacocinética , Método Duplo-Cego , Feminino , Humanos , Fatores Imunológicos/farmacocinética , Masculino , Pessoa de Meia-Idade
6.
Neurology ; 102(5): e208061, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38386949

RESUMO

BACKGROUND AND OBJECTIVES: Zagotenemab (LY3303560), a monoclonal antibody that preferentially targets misfolded, extracellular, aggregated tau, was assessed in the PERISCOPE-ALZ phase 2 study to determine its ability to slow cognitive and functional decline relative to placebo in early symptomatic Alzheimer disease (AD). METHODS: Participants were enrolled across 56 sites in North America and Japan. Key eligibility criteria included age of 60-85 years, Mini-Mental State Examination score of 20-28, and intermediate levels of brain tau on PET imaging. In this double-blind study, participants were equally randomized to 1,400 mg or 5,600 mg of zagotenemab, or placebo (IV infusion every 4 weeks for 100 weeks). The primary outcome was change on the Integrated AD Rating Scale (iADRS) assessed by a Bayesian Disease Progression model. Secondary measures include mixed model repeated measures analysis of additional cognitive and functional endpoints as well as biomarkers of AD pathology. RESULTS: A total of 360 participants (mean age = 75.4 years; female = 52.8%) were randomized, and 218 completed the treatment period. Demographics and baseline characteristics were reasonably balanced among arms. The mean disease progression ratio (proportional decline in the treated vs placebo group) with 95% credible intervals for the iADRS was 1.10 (0.959-1.265) for the zagotenemab low-dose group and 1.05 (0.907-1.209) for the high-dose, where a ratio less than 1 favors the treatment group. Secondary clinical endpoint measures failed to show a drug-placebo difference in favor of zagotenemab. No treatment effect was demonstrated by flortaucipir PET, volumetric MRI, or neurofilament light chain (NfL) analyses. A dose-related increase in plasma phosphorylated tau181 and total tau was demonstrated. Zagotenemab treatment groups reported a higher incidence of adverse events (AEs) (85.1%) compared with the placebo group (74.6%). This difference was not attributable to any specific AE or category of AEs. DISCUSSION: In participants with early symptomatic AD, zagotenemab failed to achieve significant slowing of clinical disease progression compared with placebo. Imaging biomarker and plasma NfL findings did not show evidence of pharmacodynamic activity or disease modification. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov: NCT03518073. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with early symptomatic AD, zagotenemab does not slow clinical disease progression.


Assuntos
Doença de Alzheimer , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/psicologia , Anticorpos Monoclonais/uso terapêutico , Teorema de Bayes , Progressão da Doença , Método Duplo-Cego , Resultado do Tratamento , Masculino
7.
Magn Reson Med ; 65(1): 128-37, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20939094

RESUMO

Due to methodological difficulties related to the small size, variable distribution of hippocampal arteries, and the location of the hippocampus in the proximity of middle cranial fossa, little is known about hippocampal blood flow (HBF). We have tested the utility of a pulsed arterial spin labeling sequence based on multi-shot true fast imaging in steady precession to measure HBF in 34 normal volunteers (17 women, 17 men, 26-92 years old). Flow sensitivity to a mild hypercapnic challenge was also examined. Coregistered 3D MPRAGE sequence was used to eliminate from hippocampal and cortical regions of interest all voxel with <75% of gray matter. Large blood vessels were also excluded. HBF in normal volunteers averaged 61.2 ± 9.0 mL/(100 g min). There was no statistically significant age or gender effect. Under a mild hypercapnia challenge (end tidal CO(2) pressure increase of 6.8 ± 1.9 mmHg over the baseline), HBF response was 14.1 ± 10.8 mL/(100 g min), whereas cortical gray matter flow increased by 18.0 ± 12.2 mL/(100 g min). Flow response among women was significantly larger than in the men. The average absolute difference between two successive HBF measures was 3.6 mL/(100 g min) or 5.4%. The 3T true fast imaging in steady precession arterial spin labeling method offers a HBF measurement strategy that combines good spatial resolution, sensitivity, and minimal image distortions.


Assuntos
Envelhecimento/fisiologia , Artérias Cerebrais/fisiologia , Hipocampo/fisiologia , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Velocidade do Fluxo Sanguíneo/fisiologia , Artérias Cerebrais/anatomia & histologia , Feminino , Hipocampo/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Marcadores de Spin
8.
Proc Natl Acad Sci U S A ; 104(48): 19067-72, 2007 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-18003925

RESUMO

Having a parent affected with late-onset Alzheimer's disease (AD) is a risk factor for developing AD among cognitively normal subjects. We examined whether cognitively normal subjects with a parental family history of AD show cerebral metabolic rate of glucose (CMRglc) reductions consistent with AD as compared with those without a family history and whether there are parent gender effects. Forty-nine 50- to 80-year-old normal subjects were examined who received clinical, neuropsychological, and 2-[(18)F]fluoro-2-deoxy-d-glucose-positron emission tomography examinations, including 16 subjects with a maternal (FHm) and eight with a paternal (FHp) family history of AD and 25 with no family history (FH(-)). FH groups were comparable for demographic and neuropsychological measures. As compared with both FH(-) and FHp groups, FHm subjects showed CMRglc reductions in the same regions as clinically affected AD patients, involving the posterior cingulate cortex/precuneus, parietotemporal and frontal cortices, and medial temporal lobes (P < 0.05, corrected for multiple comparisons). These effects remained significant after accounting for possible risk factors for AD, including age, gender, education, apolipoprotein E genotype, and subjective memory complaints. No CMRglc differences were found between FHp and FH(-) subjects. This study shows a relationship between reduced CMRglc in AD-vulnerable brain regions and a maternal family history of AD in cognitively normal individuals.


Assuntos
Doença de Alzheimer/genética , Córtex Cerebral/metabolismo , Impressão Genômica , Glucose/metabolismo , Tomografia por Emissão de Pósitrons , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/metabolismo , Apolipoproteína E4/genética , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Feminino , Radioisótopos de Flúor/farmacocinética , Fluordesoxiglucose F18/farmacocinética , Genes Mitocondriais , Heterogeneidade Genética , Predisposição Genética para Doença , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mães , Estudos Retrospectivos , Risco
9.
Neurol Neurochir Pol ; 44(4): 339-49, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20827607

RESUMO

BACKGROUND AND PURPOSE: It is not clear how cardiovascular autonomic nervous system dysfunction can affect falls in Parkinson disease (PD) patients. The aim of the study was to evaluate cardiovascular autonomic responses to orthostatic stress and occurrence of falls in PD patients over a period of 1-2 years. MATERIAL AND METHODS: In 53 patients, who either experienced at least one fall during 12 months preceding the study onset (fallers) or did not fall (non-fallers), we monitored RR intervals (RRI), heart rate (HR) and systolic (SBP) and diastolic (DBP) blood pressure, and calculated the coefficient of variation of RRI (RRI-CoV) and the ratio of low to high frequency spectral powers of RRI oscillations (LF/HF) at rest and upon tilting at study entry and after at least 12 months. Based on the number of falls at study closure, we identified three subgroups: non-fallers, chronic fallers, and new fallers. RESULTS: At study entry, RR-CoV, SBP, or DBP did not differ between fallers and non-fallers, while LF/HF ratios were lower in fallers than non-fallers at rest and upon tilting. After the follow-up period, HR and RRI-CoV responses to head-up tilt were reduced in new fallers as compared to study entry, whereas these variables remained unchanged during the study in non-fallers and chronic fallers. Prevalence of orthostatic hypotension did not differ between subgroups of patients. CONCLUSIONS: Cardiac responses to orthostatic stress deteriorate in PD patients who begin to fall. Orthostatic blood pressure responses remain unchanged over time and are not associated with falls in PD.


Assuntos
Acidentes por Quedas , Doenças do Sistema Nervoso Autônomo/etiologia , Sistema Cardiovascular/fisiopatologia , Hipotensão Ortostática/etiologia , Doença de Parkinson/complicações , Estresse Fisiológico , Adulto , Idoso , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea , Sistema Cardiovascular/inervação , Feminino , Hemodinâmica , Humanos , Hipotensão Ortostática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Polônia , Postura , Fatores de Risco
10.
Hum Brain Mapp ; 30(3): 874-82, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18381771

RESUMO

OBJECTIVES: Magnetic resonance (MRI) studies rely on sulcal boundaries to delineate the human entorhinal cortex (EC) and typically show that EC size is reduced in Alzheimer's disease (AD) and a predictor of future dementia. However, it is unknown if variations in the EC sulcal patterns are associated with AD. We classified the lateral EC sulcal boundary as either a rhinal or collateral pattern and tested the hypotheses that the rhinal pattern was (1) more common in AD and (2) associated with a smaller EC size. EXPERIMENTAL DESIGN: MRI was used to determine the prevalence of the rhinal and collateral EC patterns in 421 subjects (212 AD, 107 old normal (ONL), and 102 young NL (YNL). Anatomical validation studies of normal subjects were conducted at postmortem in 34 brain hemispheres and in vivo with 21 MRI volume studies. EC pattern reliability was studied with MRI in both cross-sectional and longitudinal designs. PRINCIPAL OBSERVATIONS: The rhinal pattern was more frequent in the right hemisphere in AD (47%) compared with ONL (28%, odds ratio = 2.25, P = 0.001). EC pattern was not related to ApoE genotype. The validations showed that the EC sulcal pattern was not associated with the neuronal number, surface area, or volume of the EC. In patients with antemortem MRI studied at postmortem it was equivalently determined, that EC patterns are reliably determined on MRI and do not change with the progressive atrophy of AD. CONCLUSIONS: The data indicate that the right hemisphere rhinal pattern is over represented in AD as compared with control. However, in normal subjects the EC rhinal pattern is not associated with a diminished EC tissue size. It remains to be demonstrated if the right EC rhinal sulcus pattern association with AD reflects genetic or developmental influences.


Assuntos
Doença de Alzheimer/patologia , Córtex Entorrinal/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
11.
J Alzheimers Dis ; 16(2): 351-62, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19221425

RESUMO

Little is known of combined utility of magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF) biomarkers for prediction of Alzheimer's disease (AD) and longitudinal data is scarce. We examined these biomarkers at baseline and longitudinally in incipient AD. Forty-five subjects [21 controls (NL-NL), 16 stable MCI (MCI-MCI), 8 MCI who declined to AD (MCI-AD)] received MRI and lumbar puncture at baseline and after 2 years. CSF measures included total and phosphorylated tau (T-tau, P-tau(231)), amyloid-beta (Abeta(42)/Abeta(40)) and isoprostane. Voxel-based morphometry identified gray matter concentration (GMC) differences best distinguishing study groups and individual GMC values were calculated. Rate of medial temporal lobe (MTL) atrophy was examined using regional boundary shift (rBS) method. At baseline, for MRI, MCI-AD showed reduced GMC-MTL, and for CSF higher CSF T-tau, P-tau(231), IP and lower Abeta(42)/Abeta(40) as compared with MCI-MCI or NL-NL. Longitudinally, rBS-MTL atrophy was higher in MCI-AD than in either MCI-MCI or NL-NL, particularly in the left hemisphere. CSF data showed longitudinally greater increases of isoprostane in MCI-AD as compared with NL-NL. Combining baseline CSF-P-tau(231) and GMC-MTL significantly increased overall prediction of AD from 74% to 84% (p(step)<0.05). These results provide support for including multiple modalities of biomarkers in the identification of memory clinic patients at increased risk for dementia.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/patologia , Imageamento por Ressonância Magnética/métodos , Idoso , Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Apolipoproteína E4/genética , Área Sob a Curva , Transtornos Cognitivos/líquido cefalorraquidiano , Transtornos Cognitivos/complicações , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/genética , Feminino , Lateralidade Funcional , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Processamento de Imagem Assistida por Computador , Isoprostanos/líquido cefalorraquidiano , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Sensibilidade e Especificidade , Proteínas tau/líquido cefalorraquidiano
12.
Brain Imaging Behav ; 13(1): 200-209, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28942477

RESUMO

Cognitive impairment in Parkinson's disease (PD) is related to the reorganization of brain topology. Although drug challenge studies have proven how levodopa treatment can modulate functional connectivity in brain circuits, the role of chronic dopaminergic therapy on cognitive status and functional connectivity has never been investigated. We sought to characterize brain functional topology in mid-stage PD patients under chronic antiparkinson treatment and explore the presence of correlation between reorganization of brain architecture and specific cognitive deficits. We explored networks topology and functional connectivity in 16 patients with PD and 16 matched controls through a graph theoretical analysis of resting state-functional MRI data, and evaluated the relationships between network metrics and cognitive performance. PD patients showed a preserved small-world network topology but a lower clustering coefficient in comparison with healthy controls. Locally, PD patients showed lower degree of connectivity and local efficiency in many hubs corresponding to functionally relevant areas. Four disconnected subnetworks were also identified in regions responsible for executive control, sensory-motor control and planning, motor coordination and visual elaboration. Executive functions and information processing speed were directly correlated with degree of connectivity and local efficiency in frontal, parietal and occipital areas. While functional reorganization appears in both motor and cognitive areas, the clinical expression of network imbalance seems to be partially compensated by the chronic levodopa treatment with regards to the motor but not to the cognitive performance. In a context of reduced network segregation, the presence of higher local efficiency in hubs regions correlates with a better cognitive performance.


Assuntos
Antiparkinsonianos/uso terapêutico , Encéfalo/fisiopatologia , Cognição , Doença de Parkinson/fisiopatologia , Doença de Parkinson/psicologia , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Mapeamento Encefálico/métodos , Cognição/efeitos dos fármacos , Cognição/fisiologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/tratamento farmacológico , Estudos Prospectivos , Descanso
13.
Neuropsychology ; 22(4): 469-84, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18590359

RESUMO

The aim of the study was to compare the performance of Robust and Conventional neuropsychological norms in predicting clinical decline among healthy adults and in mild cognitive impairment (MCI). The authors developed Robust baseline cross sectional and longitudinal change norms from 113 healthy participants retaining a normal diagnosis for at least 4 years. Baseline Conventional norms were separately created for 256 similar healthy participants without follow-up. Conventional and Robust norms were tested in an independent cohort of longitudinally studied healthy (n=223), MCI (n=136), and Alzheimer's disease (AD, n=162) participants; 84 healthy participants declined to MCI or AD (NL-->DEC), and 44 MCI declined to AD (MCI-->AD). Compared to Conventional norms, baseline Robust norms correctly identified a higher proportion of NL-->DEC with impairment in delayed memory and attention-language domains. Both norms predicted decline from MCI-->AD. Change norms for delayed memory and attention-language significantly incremented baseline classification accuracies. These findings indicate that Robust norms improve identification of healthy individuals who will decline and may be useful for selecting at-risk participants for research studies and early interventions.


Assuntos
Envelhecimento , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/fisiopatologia , Testes Neuropsicológicos/estatística & dados numéricos , Testes Neuropsicológicos/normas , Idoso , Atenção/fisiologia , Progressão da Doença , Feminino , Humanos , Idioma , Estudos Longitudinais , Masculino , Memória/fisiologia , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Valores de Referência , Sensibilidade e Especificidade
14.
Alzheimers Dement ; 4(4): 242-50, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18631974

RESUMO

The molecular and cellular mechanisms responsible for the etiology and pathogenesis of Alzheimer's disease (AD) have not been defined; however, inflammation within the brain is thought to play a pivotal role. Studies suggest that peripheral infection/inflammation might affect the inflammatory state of the central nervous system. Chronic periodontitis is a prevalent peripheral infection that is associated with gram-negative anaerobic bacteria and the elevation of serum inflammatory markers including C-reactive protein. Recently, chronic periodontitis has been associated with several systemic diseases including AD. In this article we review the pathogenesis of chronic periodontitis and the role of inflammation in AD. In addition, we propose several potential mechanisms through which chronic periodontitis can possibly contribute to the clinical onset and progression of AD. Because chronic periodontitis is a treatable infection, it might be a readily modifiable risk factor for AD.


Assuntos
Doença de Alzheimer/etiologia , Inflamação/complicações , Doenças Periodontais/complicações , Doença de Alzheimer/patologia , Progressão da Doença , Humanos , Inflamação/microbiologia , Inflamação/patologia , Doenças Periodontais/patologia , Fatores de Risco
15.
Exp Gerontol ; 42(1-2): 129-38, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16839732

RESUMO

Neuroimaging is being increasingly used to complement clinical assessments in the early detection of Alzheimer's disease (AD). Structural magnetic resonance imaging (MRI) and metabolic positron emission tomography (FDG-PET) are the most clinically used and promising modalities to detect brain abnormalities in individuals who might be at risk for AD but who have not yet developed symptoms. The knowledge of established risk factors for AD enabled investigators to develop enrichment strategies for longitudinal imaging studies to reduce the sample sizes and study duration. The present review focuses on the results obtained by MRI and FDG-PET studies that examined the preclinical AD stages in several at risk populations: (1) individuals from families with autosomal dominant early-onset AD (FAD), (2) patients with mild cognitive impairment (MCI), particularly in memory, who are at very high risk for declining to AD with an estimated decline rate of 10-30% per year, (3) normal young and middle-age subjects carriers of known susceptibility genes for late-onset AD such as the Apolipoprotein E (ApoE) E4 allele, and (4) as age is the main risk factor for AD, normal elderly individuals followed to the onset of MCI and AD. Overall, these studies show that the use of imaging for the early detection of AD is successful even in the earlier stages of disease when clinical symptoms are not fully expressed and the regional brain damage may be limited.


Assuntos
Doença de Alzheimer/diagnóstico , Encéfalo/patologia , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Doença de Alzheimer/genética , Apolipoproteínas E/genética , Encéfalo/diagnóstico por imagem , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/genética , Diagnóstico Precoce , Fluordesoxiglucose F18 , Genótipo , Humanos , Compostos Radiofarmacêuticos
16.
Przegl Lek ; 63(8): 616-9, 2006.
Artigo em Polonês | MEDLINE | ID: mdl-17441368

RESUMO

BACKGROUND: To prevent the recurrence of primary intracerebral hemorrhage (PIH) it is important to identify patients with underlying structural vascular abnormalities (VA). According to previous study data-- the site of hemorrhage, the patient's age and pre-existing hypertension affect the likelihood of finding VA. However, the indications for angiography, the gold standard for the diagnosis of VA, still remain controversial. PURPOSE: To assess the frequency of VA and to determine features that might increase the probability of finding VA in patients with PIH. MATERIAL AND METHODS: 100 patients with PIH, without a history of trauma, coagulopathy, or known pre-existing brain abnormality, who were admitted to the Stroke Unit of the Department of Neurology, Jagiellonian University, between January 1999 and November 2000 entered this prospectively designed study. In the group of 96 patients, 53 persons underwent conventional angiography within 14 days of stroke onset (in 4 cases we found bleeding into the tumor and these patients were not included in further analysis). RESULTS: Vascular abnormalities were found in 14 of 53 patients (26.4%); ruptured aneurysms in 9 patients (17.0%), arteriovenous malformations (AVM) in 3 patients (5.7%), venous angioma in 1 patient (1.8%) and cavernous angioma in 1 patient (1.9%). Vascular malformations were found in 12 of 25 patients with lobar hemorrhage, in 1 of 8 patients with hemorrhage originating in the thalamus and in 1 of 2 patients with hemorrhage originating in the pons. Angiographic findings were negative in 8 patients with hemorrhage in the periventricular white matter, in 8 with hemorrhage originating in the basal ganglia and in 2 patients with hemorrhage in the cerebellum. Patients with VA were significantly younger than patients without VA (49.9 +/- 11.7 years and 58.7 +/- 13.3 years respectively, p = 0.03) and they had a history of hypertension significantly less often (50.0% and 89.7%, p = 0.001). Intraventricular hemorrhage and subarachnoid bleeding occurred in a similar percentage of patients with ICH, independent of whether or not they had VA (28.6% and 38.5%; 21.4% and 10.3% respectively, p = n.s.). CONCLUSIONS: (1) A vascular abnormality is the cause of about 26% of ICH, with a higher likelihood in younger patients and with lobar hemorrhage. (2) A history of hypertension does not exclude the presence of VA. (3) Intraventricular hemorrhage or subarachnoid bleeding does not predict the presence of VA.


Assuntos
Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/etiologia , Malformações Arteriovenosas Intracranianas/complicações , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Cerebral , Hemorragia Cerebral/cirurgia , Feminino , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
17.
Neurodegener Dis Manag ; 6(5): 431-46, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27599588

RESUMO

Freezing of gait (FOG) is 'an episodic inability to generate effective stepping in the absence of any known cause other than parkinsonism or high level gait disorders'. FOG is one of the most disabling symptoms in Parkinson's disease, especially in its more advanced stages. Early recognition is important as FOG is related to higher fall risk and poorer prognosis. Although specific treatments are still elusive, there have been recent advances in the development of new therapeutic approaches. The aim of this review is to present the latest knowledge regarding the phenomenology, pathogenesis, diagnostic assessment and conventional treatment of FOG in Parkinson's disease. A review of the evidence supporting noninvasive brain stimulation will follow to highlight the potential of these strategies.


Assuntos
Transtornos Neurológicos da Marcha/etiologia , Doença de Parkinson/complicações , Marcha , Transtornos Neurológicos da Marcha/diagnóstico , Transtornos Neurológicos da Marcha/fisiopatologia , Transtornos Neurológicos da Marcha/terapia , Humanos , Doença de Parkinson/fisiopatologia
18.
Neurology ; 87(18): 1907-1915, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27708129

RESUMO

OBJECTIVE: To assess whether multifocal, high-frequency repetitive transcranial magnetic stimulation (rTMS) of motor and prefrontal cortex benefits motor and mood symptoms in patients with Parkinson disease (PD). METHODS: Patients with PD and depression were enrolled in this multicenter, double-blind, sham-controlled, parallel-group study of real or realistic (electric) sham rTMS. Patients were randomized to 1 of 4 groups: bilateral M1 ( + sham dorsolateral prefrontal cortex [DLPFC]), DLPFC ( + sham M1), M1 + DLPFC, or double sham. The TMS course consisted of 10 daily sessions of 2,000 stimuli for the left DLPFC and 1,000 stimuli for each M1 (50 × 4-second trains of 40 stimuli at 10 Hz). Patients were evaluated at baseline, at 1 week, and at 1, 3, and 6 months after treatment. Primary endpoints were changes in motor function assessed with the Unified Parkinson's Disease Rating Scale-III and in mood with the Hamilton Depression Rating Scale at 1 month. RESULTS: Of the 160 patients planned for recruitment, 85 were screened, 61 were randomized, and 50 completed all study visits. Real M1 rTMS resulted in greater improvement in motor function than sham at the primary endpoint (p < 0.05). There was no improvement in mood in the DLPFC group compared to the double-sham group, as well as no benefit to combining M1 and DLPFC stimulation for either motor or mood symptoms. CONCLUSIONS: In patients with PD with depression, M1 rTMS is an effective treatment of motor symptoms, while mood benefit after 2 weeks of DLPFC rTMS is not better than sham. Targeting both M1 and DLPFC in each rTMS session showed no evidence of synergistic effects. CLINICALTRIALSGOV IDENTIFIER: NCT01080794. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that in patients with PD with depression, M1 rTMS leads to improvement in motor function while DLPFC rTMS does not lead to improvement in depression compared to sham rTMS.


Assuntos
Transtornos do Humor/etiologia , Transtornos do Humor/terapia , Doença de Parkinson/complicações , Córtex Pré-Frontal/fisiologia , Idoso , Análise de Variância , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/terapia , Escalas de Graduação Psiquiátrica , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
19.
Brain ; 127(Pt 9): 2090-8, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15240436

RESUMO

This study was performed to assess cutaneous nerve fibre loss in conjunction with temperature and sweating dysfunction in familial dysautonomia (FD). In ten FD patients, we determined warm and cold thresholds at the calf and shoulder, and sweating in response to acetylcholine iontophoresis over the calf and forearm. Punch skin biopsies from calf and back were immunostained and imaged to assess nerve fibre density and neuropeptide content. Mean temperature thresholds and baseline sweat rate were elevated in the patients, while total sweat volume and response time did not differ from controls. The average density of epidermal nerve fibres was greatly diminished in the calf and back. There was also severe nerve loss from the subepidermal neural plexus (SNP) and deep dermis. The few sweat glands present within the biopsies had had reduced innervation density. Substance P immunoreactive (-ir) and calcitonin gene related peptide-ir (CGRP-ir) were virtually absent, but vasoactive intestinal peptide-ir (VIP-ir) nerves were present in the SNP. Empty Schwann cell sheaths were observed. Temperature perception was more impaired than sweating. Epidermal nerve fibre density was found to be profoundly reduced in FD. Decreased SP and CGRP-ir nerves suggest that the FD gene mutation causes secondary neurotransmitter depletions. Empty Schwann cell sheaths and VIP-ir nerves suggest active denervation and regeneration.


Assuntos
Temperatura Corporal/fisiologia , Disautonomia Familiar/fisiopatologia , Pele/inervação , Sudorese/fisiologia , Adolescente , Adulto , Disautonomia Familiar/patologia , Epiderme/inervação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Neuropeptídeos/análise , Células de Schwann/patologia , Glândulas Sudoríparas/patologia
20.
Neuroimaging Clin N Am ; 15(4): 803-26, x, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16443492

RESUMO

The goal of this article is to review the role of structural neuroimaging in the diagnosis of Alzheimer's disease (AD). We present relevant neuroanatomy, highlight progress in the domain of AD imaging, and review the clinical characteristics of the prodromal phase of AD. We describe the history of the diagnostic issue by examining at cross-section and longitudinally the differences between patients who have AD and normal controls. We also present how subsequent works applied these characteristic traits to the early detection of the prodromal disease and to prediction of future decline. The article delineates the differences between subjects who have mild cognitive impairment and AD, which illustrate the spreading of the pathology with disease progression. The last section describes problems encountered in the differential diagnosis.


Assuntos
Doença de Alzheimer/diagnóstico , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Transtornos Cognitivos/diagnóstico , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Diagnóstico Diferencial , Progressão da Doença , Diagnóstico Precoce , Humanos , Valor Preditivo dos Testes
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