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1.
Front Neurol ; 15: 1360705, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38566852

RESUMO

Cases of iatrogenic cerebral amyloid angiopathy (CAA) have been increasingly reported recently, particularly those associated with neurosurgery. Preclinical studies have shown taxifolin to be promising for treating CAA. We describe a young 42-year-old man with a history of childhood traumatic brain injury that required a craniotomy for hematoma evacuation. He later presented with recurrent lobar intracerebral hemorrhage (ICH) decades later, which was histologically confirmed to be CAA. Serial 11C-Pittsburgh compound B positron emission tomography (11C-PiB-PET) imaging showed a 24% decrease in global standardized uptake value ratio (SUVR) at 10 months after taxifolin use. During this period, the patient experienced clinical improvement with improved consciousness and reduced recurrent ICH frequency, which may be partly attributable to the potential amyloid-ß (Aß) clearing the effect of taxifolin. However, this effect seemed to have diminished at 15 months, CAA should be considered in young patients presenting with recurrent lobar ICH with a history of childhood neurosurgery, and serial 11C-PiB-PET scans warrant further validation as a strategy for monitoring treatment response in CAA for candidate Aß-clearing therapeutic agents such as taxifolin.

3.
J Alzheimers Dis ; 97(2): 883-893, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38189749

RESUMO

BACKGROUND: Pilot study showed that Alzheimer's disease resemblance atrophy index (AD-RAI), a machine learning-derived MRI-based neurodegeneration biomarker of AD, achieved excellent diagnostic performance in diagnosing AD with moderate to severe dementia. OBJECTIVE: The primary objective was to validate and compare the performance of AD-RAI with conventional volumetric hippocampal measures in diagnosing AD with mild dementia. The secondary objectives were 1) to investigate the association between imaging biomarkers with age and gender among cognitively unimpaired (CU) participants; 2) to analyze whether the performance of differentiating AD with mild dementia from CU will improve after adjustment for age/gender. METHODS: AD with mild dementia (n = 218) and CU (n = 1,060) participants from 4 databases were included. We investigated the area under curve (AUC), sensitivity, specificity, and balanced accuracy of AD-RAI, hippocampal volume (HV), and hippocampal fraction (HF) in differentiating between AD and CU participants. Among amyloid-negative CU participants, we further analyzed correlation between the biomarkers with age/gender. We also investigated whether adjustment for age/gender will affect performance. RESULTS: The AUC of AD-RAI (0.93) was significantly higher than that of HV (0.89) and HF (0.89). Subgroup analysis among A + AD and A- CU showed that AUC of AD-RAI (0.97) was also higher than HV (0.94) and HF (0.93). Diagnostic performance of AD-RAI and HF was not affected by age/gender while that of HV improved after age adjustment. CONCLUSIONS: AD-RAI achieves excellent clinical validity and outperforms conventional volumetric hippocampal measures in aiding the diagnosis of AD mild dementia without the need for age adjustment.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Demência , Humanos , Doença de Alzheimer/diagnóstico por imagem , Projetos Piloto , Disfunção Cognitiva/diagnóstico , Imageamento por Ressonância Magnética/métodos , Biomarcadores , Aprendizado de Máquina
4.
Cereb Circ Cogn Behav ; 4: 100168, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37397268

RESUMO

Background and aims: Recent preclinical studies and meta-analysis of clinical trials suggested that acupuncture may improve cognition in cerebral small vessel disease (CSVD). We investigated the cerebral hemodynamics of acupuncture in subjects with CSVD and compared its impact upon the cerebral hemodynamics in normal elderly subjects. Methods: 10 subjects with CSVD (CSVD group) and 10 aged-matched control subjects who had no or insignificant CSVD (control group) were recruited. A single session of acupuncture was applied for 30 min in both groups. We assessed the effect of our acupuncture intervention on cerebral hemodynamics by transcranial Doppler ultrasound (TCD). Peak systolic velocity (PSV) and pulsatility index (PI) of the middle cerebral artery (MCA) were assessed. Results: We observed that PSV increased by a maximum of 39% at 20 min (p<0.05), while there was no significant change in PI in the CSVD group during the acupuncture session. In the control group, although we observed no significant change in PSV during the acupuncture session, there was a significant decrease in PI by a maximum of 22% at 20 min (p<0.05). No adverse events were reported during or after the procedure. Conclusion: This study suggested that our acupuncture prescription was associated with an increase in cerebral blood flow in subjects with established moderate to severe CSVD yet without apparent impact on distal vascular resistance. While, in subjects with no or insignificant CSVD, it may reduce cerebral small vessel distal vascular resistance. A larger study is needed to confirm our findings.

5.
Cereb Cortex ; 33(17): 9867-9876, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37415071

RESUMO

Menstrually-related migraine (MM) is a primary migraine in women of reproductive age. The underlying neural mechanism of MM was still unclear. In this study, we aimed to reveal the case-control differences in network integration and segregation for the morphometric similarity network of MM. Thirty-six patients with MM and 29 healthy females were recruited and underwent MRI scanning. The morphometric features were extracted in each region to construct the single-subject interareal cortical connection using morphometric similarity. The network topology characteristics, in terms of integration and segregation, were analyzed. Our results revealed that, in the absence of morphology differences, disrupted cortical network integration was found in MM patients compared to controls. The patients with MM showed a decreased global efficiency and increased characteristic path length compared to healthy controls. Regional efficiency analysis revealed the decreased efficiency in the left precentral gyrus and bilateral superior temporal gyrus contributed to the decreased network integration. The increased nodal degree centrality in the right pars triangularis was positively associated with the attack frequency in MM. Our results suggested MM would reorganize the morphology in the pain-related brain regions and reduce the parallel information processing capacity of the brain.


Assuntos
Encéfalo , Transtornos de Enxaqueca , Humanos , Feminino , Encéfalo/diagnóstico por imagem , Transtornos de Enxaqueca/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Córtex Pré-Frontal , Dor
6.
Alzheimers Dement ; 19(11): 4987-4998, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37087687

RESUMO

INTRODUCTION: We compared the machine learning-derived, MRI-based Alzheimer's disease (AD) resemblance atrophy index (AD-RAI) with plasma neurofilament light chain (NfL) level in predicting conversion of early AD among cognitively unimpaired (CU) and mild cognitive impairment (MCI) subjects. METHODS: We recruited participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) who had the following data: clinical features (age, gender, education, Montreal Cognitive Assessment [MoCA]), structural MRI, plasma biomarkers (p-tau181 , NfL), cerebrospinal fluid biomarkers (CSF) (Aß42, p-tau181 ), and apolipoprotein E (APOE) ε4 genotype. We defined AD using CSF Aß42 (A+) and p-tau181 (T+). We defined conversion (C+) if a subject progressed to the next syndromal stage within 4 years. RESULTS: Of 589 participants, 96 (16.3%) were A+T+C+. AD-RAI performed better than plasma NfL when added on top of clinical features, plasma p-tau181 , and APOE ε4 genotype (area under the curve [AUC] = 0.832 vs. AUC = 0.650 among CU, AUC = 0.853 vs. AUC = 0.805 among MCI) in predicting A+T+C+. DISCUSSION: AD-RAI outperformed plasma NfL in predicting syndromal conversion of early AD. HIGHLIGHTS: AD-RAI outperformed plasma NfL in predicting syndromal conversion among early AD. AD-RAI showed better metrics than volumetric hippocampal measures in predicting syndromal conversion. Combining clinical features, plasma p-tau181 and apolipoprotein E (APOE) with AD-RAI is the best model for predicting syndromal conversion.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Imageamento por Ressonância Magnética/métodos , Disfunção Cognitiva/líquido cefalorraquidiano , Apolipoproteínas E/genética , Biomarcadores/líquido cefalorraquidiano , Aprendizado de Máquina , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano
7.
Alzheimers Dement (N Y) ; 8(1): e12369, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36583111

RESUMO

Introduction: Cerebral small vessel disease (SVD) is an important cause of dementia that lacks effective treatment. We evaluated the efficacy and safety of cilostazol, an antiplatelet agent with potential neurovascular protective effects, in slowing the progression of white matter hyperintensities (WMHs) in stroke- and dementia-free subjects harboring confluent WMH on magnetic resonance imaging (MRI). Methods: In this single-center, randomized, double-blind, placebo-controlled study, we randomized stroke- and dementia-free subjects with confluent WMHs to receive cilostazol or placebo for 2 years in a 1:1 ratio. The primary outcome was change in WMH volume over 2 years. Secondary outcomes were changes in brain volumes, lacunes, cerebral microbleeds, perivascular space, and alterations in white matter microstructural integrity, cognition, motor function, and mood. Results: We recruited 120 subjects from October 27, 2014, to January 21, 2019. A total of 55 subjects in the cilostazol group and 54 subjects in the control group were included for intention-to-treat analysis. At 2-year follow-up, the changes in WMH volume were not statistically different between cilostazol treatment and placebo (0.3±1.0 mL vs -0.1±0.8 mL, p = 0.167). Secondary outcomes, bleeding and vascular events, were also not statistically different between the two groups. Discussion: In this trial with stroke- and dementia-free subjects with confluent WMHs, cilostazol did not impact WMH progression but demonstrated an acceptable safety profile. Future studies should address the treatment effects of cilostazol on subjects at different clinical stages of SVD.

8.
Lancet Digit Health ; 4(11): e806-e815, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36192349

RESUMO

BACKGROUND: There is no simple model to screen for Alzheimer's disease, partly because the diagnosis of Alzheimer's disease itself is complex-typically involving expensive and sometimes invasive tests not commonly available outside highly specialised clinical settings. We aimed to develop a deep learning algorithm that could use retinal photographs alone, which is the most common method of non-invasive imaging the retina to detect Alzheimer's disease-dementia. METHODS: In this retrospective, multicentre case-control study, we trained, validated, and tested a deep learning algorithm to detect Alzheimer's disease-dementia from retinal photographs using retrospectively collected data from 11 studies that recruited patients with Alzheimer's disease-dementia and people without disease from different countries. Our main aim was to develop a bilateral model to detect Alzheimer's disease-dementia from retinal photographs alone. We designed and internally validated the bilateral deep learning model using retinal photographs from six studies. We used the EfficientNet-b2 network as the backbone of the model to extract features from the images. Integrated features from four retinal photographs (optic nerve head-centred and macula-centred fields from both eyes) for each individual were used to develop supervised deep learning models and equip the network with unsupervised domain adaptation technique, to address dataset discrepancy between the different studies. We tested the trained model using five other studies, three of which used PET as a biomarker of significant amyloid ß burden (testing the deep learning model between amyloid ß positive vs amyloid ß negative). FINDINGS: 12 949 retinal photographs from 648 patients with Alzheimer's disease and 3240 people without the disease were used to train, validate, and test the deep learning model. In the internal validation dataset, the deep learning model had 83·6% (SD 2·5) accuracy, 93·2% (SD 2·2) sensitivity, 82·0% (SD 3·1) specificity, and an area under the receiver operating characteristic curve (AUROC) of 0·93 (0·01) for detecting Alzheimer's disease-dementia. In the testing datasets, the bilateral deep learning model had accuracies ranging from 79·6% (SD 15·5) to 92·1% (11·4) and AUROCs ranging from 0·73 (SD 0·24) to 0·91 (0·10). In the datasets with data on PET, the model was able to differentiate between participants who were amyloid ß positive and those who were amyloid ß negative: accuracies ranged from 80·6 (SD 13·4%) to 89·3 (13·7%) and AUROC ranged from 0·68 (SD 0·24) to 0·86 (0·16). In subgroup analyses, the discriminative performance of the model was improved in patients with eye disease (accuracy 89·6% [SD 12·5%]) versus those without eye disease (71·7% [11·6%]) and patients with diabetes (81·9% [SD 20·3%]) versus those without the disease (72·4% [11·7%]). INTERPRETATION: A retinal photograph-based deep learning algorithm can detect Alzheimer's disease with good accuracy, showing its potential for screening Alzheimer's disease in a community setting. FUNDING: BrightFocus Foundation.


Assuntos
Doença de Alzheimer , Aprendizado Profundo , Humanos , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides , Estudos Retrospectivos , Estudos de Casos e Controles
9.
Epilepsia Open ; 7(4): 570-577, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35867810

RESUMO

OBJECTIVE: As Hong Kong faced the 5th wave of the COVID-19 pandemic, the facilitators and hurdles toward effective vaccination is important for healthcare professionals to understand the vaccination gap among patients with epilepsy. METHODS: A cross-sectional, pragmatic study of COVID-19 vaccination was performed at a tertiary epilepsy center with regards to patterns of vaccination and any unusually high rate of adverse events. Patients having recent visits at the epilepsy center (4 months) had their anonymized electronic linkage records examined 12 months after the inception of vaccination program for types of vaccines, seizure demographics, and adverse events following immunization (AEFI). RESULTS: A total of 200 patients with epilepsy and their anonymized data were analyzed. The vaccine uptake was approximately 60% of that of the general population. Twice as many patients with epilepsy chose to receive mRNA vaccine as compared with inactivated vaccine. The proportion of patients who kept up-to-date with all available dosing was 7%. Patients with epilepsy with genetic etiology were least likely to receive vaccination (13/38, 34%, P = .02). There was no unreasonably high rate of unacceptable side effects after vaccination among patients with epilepsy. Only 3 patients reported worsening of seizures without meeting the criteria for AEFI. Refractory epilepsy, allergy to antiseizure medications and elder age (≥65) did not confer any significant difference in vaccination patterns or adverse effects. SIGNIFICANCE: A vaccination gap exists among epilepsy patients which calls for actionable strategies for improving vaccine uptake, including education and outreach programs.


Assuntos
COVID-19 , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Epilepsia , Vacinas , Humanos , Idoso , Estudos Transversais , Vacinas contra COVID-19/efeitos adversos , Pandemias/prevenção & controle , COVID-19/prevenção & controle , Hong Kong/epidemiologia , Vacinação/efeitos adversos , Epilepsia/tratamento farmacológico , Epilepsia/complicações , Convulsões/etiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/complicações , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Vacinas de mRNA
10.
Brain Sci ; 12(6)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35741606

RESUMO

Alzheimer's disease (AD) was recently defined as a biological construct to reflect neuropathologic status, and both abnormal amyloid and tau are required for a diagnosis of AD. We aimed to determine the proton MR spectroscopic (1H-MRS) patterns of the posterior cingulate in biologically defined AD. A total of 68 participants were included in this study, comprising 37 controls, 16 early AD, and 15 late AD, who were classified according to their amyloid and tau status and presence of hippocampal atrophy. Compared with controls, early AD showed lower N-acetylaspartate (NAA)/creatine (Cr) (p = 0.003), whereas late AD showed lower NAA/Cr and higher myoInositol (mI)/Cr (all with p < 0.05). Lower NAA/Cr correlated with a greater global amyloid load (r = −0.47, p < 0.001) and tau load (r = −0.51, p < 0.001) and allowed a discrimination of early AD from controls (p < 0.001). Subgroup analysis showed that NAA/Cr also allowed a differentiation of early AD from controls in the cognitively unimpaired subjects, with an area under the receiver operating characteristics curve, sensitivity, and specificity of 0.96, 100%, and 83.8%, respectively. Lower posterior cingulate NAA levels may help to inform underlying neuropathologic changes in the early stage of AD.

11.
Int J Stroke ; 17(5): 517-525, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34109903

RESUMO

BACKGROUND: Stroke not only substantially increases the risk of incident dementia early after stroke but also the risk remains elevated years after. AIM: We aimed to determine the risk factors of dementia onset more than three to six months after stroke or transient ischemic attack. METHODS: This is a single-center prospective cohort study. We recruited consecutive subjects with stroke/transient ischemic attack without early-onset dementia. We conducted an annual neuropsychological assessment for five years. We investigated the association between baseline demographic, clinical, genetic (APOEɛ4 allele), and radiological factors as well as incident recurrent stroke with delayed-onset dementia using Cox proportional hazards models. RESULTS: In total, 1007 patients were recruited, of which 88 with early-onset dementia and 162 who lost to follow-ups were excluded. Forty-nine (6.5%) out of 757 patients have incident delayed-onset dementia. The presence of ≥3 lacunes, history of ischemic heart disease, history of ischemic stroke, and a lower baseline Hong Kong version of the Montreal Cognitive Assessment (MoCA) score were significantly associated with delayed-onset dementia. APOEɛ4 allele, medial temporal lobe atrophy, and recurrent stroke were not predictive. CONCLUSION: The presence of ≥3 lacunes, history of ischemic heart disease, history of ischemic stroke, and a lower baseline MoCA score are associated with delayed-onset dementia after stroke/transient ischemic attack.


Assuntos
Demência , Ataque Isquêmico Transitório , AVC Isquêmico , Isquemia Miocárdica , Acidente Vascular Cerebral , Estudos de Coortes , Demência/etiologia , Demência/genética , Humanos , Ataque Isquêmico Transitório/complicações , Ataque Isquêmico Transitório/epidemiologia , Estudos Longitudinais , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/psicologia
12.
Int J Stroke ; 17(4): 444-454, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33724087

RESUMO

BACKGROUND: Depicting the time trends of ischemic stroke subtypes may inform healthcare resource allocation on etiology-based stroke prevention and treatment. AIM: To reveal the evolving ischemic stroke subtypes from 2004 to 2018. METHODS: We determined the stroke etiologies of consecutive first-ever transient ischemic attack or ischemic stroke patients admitted to a regional hospital in Hong Kong from 2004 to 2018. We analyzed the age-standardized incidences and the two-year recurrence rate of major ischemic stroke subtypes. RESULTS: Among 6940 patients admitted from 2004 to 2018, age-standardized incidence of ischemic stroke declined from 187.0 to 127.4 per 100,000 population (p < 0.001), driven by the decrease in large artery disease (43.0-9.67 per 100,000 population (p < 0.001)), and small vessel disease (71.9-45.7 per 100,000 population (p < 0.001)). Age-standardized incidence of cardioembolic stroke did not change significantly (p = 0.2). Proportion of cardioembolic stroke increased from 20.4% in 2004-2006 to 29.3% in 2016-2018 (p < 0.001). Two-year recurrence rate of intracranial atherothrombotic stroke reduced from 19.3% to 5.1% (p < 0.001) with increased prescriptions of statin (p < 0.001) and dual antiplatelet therapy (p < 0.001). In parallel with increased anticoagulation use across the study period (p < 0.001), the two-year recurrence of AF-related stroke reduced from 18.9% to 6% (p < 0.001). CONCLUSION: Etiology-based risk factor control might have led to the diminishing stroke incidences related to atherosclerosis. To tackle the surge of AF-related strokes, arrhythmia screening, anticoagulation usage, and mechanical thrombectomy service should be reinforced. Comparable preventive strategies might alleviate the enormous stroke burden in mainland China.


Assuntos
Fibrilação Atrial , AVC Embólico , AVC Isquêmico , Acidente Vascular Cerebral , Anticoagulantes , Fibrilação Atrial/epidemiologia , Hospitais , Humanos , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia
13.
Stroke Vasc Neurol ; 7(3): 182-189, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34880113

RESUMO

OBJECTIVES: The predisposition of intracranial atherosclerotic disease (ICAD) to East Asians over Caucasians infers a genetic basis which, however, remains largely unknown. Higher prevalence of vascular risk factors (VRFs) in Chinese over Caucasian patients who had a stroke, and shared risk factors of ICAD with other stroke subtypes indicate genes related to VRFs and/or other stroke subtypes may also contribute to ICAD. METHODS: Unrelated symptomatic patients with ICAD were recruited for genome sequencing (GS, 60-fold). Rare and potentially deleterious single-nucleotide variants (SNVs) and small insertions/deletions (InDels) were detected in genome-wide and correlated to genes related to VRFs and/or other stroke subtypes. Rare aneuploidies, copy number variants (CNVs) and chromosomal structural rearrangements were also investigated. Lastly, candidate genes were used for pathway and gene ontology enrichment analysis. RESULTS: Among 92 patients (mean age at stroke onset 61.0±9.3 years), GS identified likely ICAD-associated rare genomic variants in 54.3% (50/92) of patients. Forty-eight patients (52.2%, 48/92) had 59 rare SNVs/InDels reported or predicted to be deleterious in genes related to VRFs and/or other stroke subtypes. None of the 59 rare variants were identified in local subjects without ICAD (n=126). 31 SNVs/InDels were related to conventional VRFs, and 28 were discovered in genes related to other stroke subtypes. Our study also showed that rare CNVs (n=7) and structural rearrangement (a balanced translocation) were potentially related to ICAD in 8.7% (8/92) of patients. Lastly, candidate genes were significantly enriched in pathways related to lipoprotein metabolism and cellular lipid catabolic process. CONCLUSIONS: Our GS study suggests a role of rare genomic variants with various variant types contributing to the development of ICAD in Chinese patients.


Assuntos
Arteriosclerose Intracraniana , Acidente Vascular Cerebral , Povo Asiático/genética , China/epidemiologia , Genômica , Humanos , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico por imagem , Arteriosclerose Intracraniana/genética , Acidente Vascular Cerebral/epidemiologia
14.
Aging (Albany NY) ; 13(10): 13496-13514, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34091443

RESUMO

Alzheimer's Disease-resemblance atrophy index (AD-RAI) is an MRI-based machine learning derived biomarker that was developed to reflect the characteristic brain atrophy associated with AD. Recent study showed that AD-RAI (≥0.5) had the best performance in predicting conversion from mild cognitive impairment (MCI) to dementia and from cognitively unimpaired (CU) to MCI. We aimed to validate the performance of AD-RAI in detecting preclinical and prodromal AD. We recruited 128 subjects (MCI=50, CU=78) from two cohorts: CU-SEEDS and ADNI. Amyloid (A+) and tau (T+) status were confirmed by PET (11C-PIB, 18F-T807) or CSF analysis. We investigated the performance of AD-RAI in detecting preclinical and prodromal AD (i.e. A+T+) among MCI and CU subjects and compared its performance with that of hippocampal measures. AD-RAI achieved the best metrics among all subjects (sensitivity 0.74, specificity 0.91, accuracy 85.94%) and among MCI subjects (sensitivity 0.92, specificity 0.81, accuracy 86.00%) in detecting A+T+ subjects over other measures. Among CU subjects, AD-RAI yielded the best specificity (0.95) and accuracy (85.90%) over other measures, while hippocampal volume achieved a higher sensitivity (0.73) than AD-RAI (0.47) in detecting preclinical AD. These results showed the potential of AD-RAI in the detection of early AD, in particular at the prodromal stage.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/diagnóstico , Imageamento por Ressonância Magnética , Sintomas Prodrômicos , Idoso , Doença de Alzheimer/patologia , Atrofia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/diagnóstico por imagem , Estudos de Coortes , Feminino , Hipocampo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Temporal/patologia
17.
J Alzheimers Dis ; 79(3): 1023-1032, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33459705

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) provides objective information about brain structural atrophy in patients with Alzheimer's disease (AD). This multi-structural atrophic information, when integrated as a single differential index, has the potential to further elevate the accuracy of AD identification from normal control (NC) compared to the conventional structure volumetric index. OBJECTIVE: We herein investigated the performance of such an MRI-derived AD index, AD-Resemblance Atrophy Index (AD-RAI), as a neuroimaging biomarker in clinical scenario. METHOD: Fifty AD patients (19 with the Amyloid, Tau, Neurodegeneration (ATN) results assessed in cerebrospinal fluid) and 50 age- and gender-matched NC (19 with ATN results assessed using positron emission tomography) were recruited in this study. MRI-based imaging biomarkers, i.e., AD-RAI, were quantified using AccuBrain®. The accuracy, sensitivity, specificity, and area under the ROC curve (AUC) of these MRI-based imaging biomarkers were evaluated with the diagnosis result according to clinical criteria for all subjects and ATN biological markers for the subgroup. RESULTS: In the whole groups of AD and NC subjects, the accuracy of AD-RAI was 91%, sensitivity and specificity were 88% and 96%, respectively, and the AUC was 92%. In the subgroup of 19 AD and 19 NC with ATN results, AD-RAI results matched completely with ATN classification. AD-RAI outperforms the volume of any single brain structure measured. CONCLUSION: The finding supports the hypothesis that MRI-derived composite AD-RAI is a more accurate imaging biomarker than individual brain structure volumetry in the identification of AD from NC in the clinical scenario.


Assuntos
Doença de Alzheimer/diagnóstico , Encéfalo/patologia , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Atrofia , Biomarcadores , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
18.
Chin Med J (Engl) ; 134(2): 143-150, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33410627

RESUMO

ABSTRACT: Age-related sporadic cerebral small vessel disease (CSVD) has gained increasing attention over the past decades because of its increasing prevalence associated with an aging population. The widespread application of and advances in brain magnetic resonance imaging in recent decades have significantly increased researchers' understanding in the in vivo evolution of CSVD, its impact upon the brain, its risk factors, and the mechanisms that explain the various clinical manifestation associated with sporadic CSVD. In this review, we aimed to provide an update on the pathophysiology, risk factors, biomarkers, and the determinants and spectrum of the clinical manifestation of sporadic CSVD.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Pandemias , Idoso , Envelhecimento , Encéfalo/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/epidemiologia , Humanos , Imageamento por Ressonância Magnética
19.
Alzheimers Dement (N Y) ; 7(1): e12224, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35005205

RESUMO

INTRODUCTION: The benefit and risk of aerobic exercise among older people harboring advanced cerebral small vessel disease (CSVD) upon cognition, mood, and motor functions are unknown. METHODS: This rater-blind randomized trial examined effects of a 24-week aerobic exercise training (60 min/session, twice/week) upon clinical (cognition, mood, motor functions) and hemodynamic (pulse pressure [PP], blood pressure [BP], pulsatility index) measures in older people harboring moderate to severe CSVD, as evidenced by confluent white matter hyperintensity and/or ≥2 lacunes on magnetic resonance imaging. We further investigated interactions between treatment conditions and hemodynamics measures. RESULTS: Fifty-three and 54 subjects were randomized into the active and control group, respectively. There was no between-group difference in any of the clinical outcomes. The active group had a greater between-group reduction in systolic BP and PP than the control group. Within-group comparison showed that global cognition of the active group remained similar at end of the study compared to baseline, whereas it declined significantly in the control group. We observed "diverging" interaction effects in that greater reduction in systolic BP/PP was associated with greater improvement in memory functions and global cognition but worsening in processing speed in the active group. Side effects were comparable between the two groups. DISCUSSION: Future study should investigate the mechanisms of the diverging impacts of aerobic exercise upon different cognitive domains so that the benefit-risk ratio of aerobic exercise in older people harboring more advanced CSVD can be better defined.

20.
J Clin Neurosci ; 83: 108-111, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33317883

RESUMO

BACKGROUND: Serum neurofilament light chain (sNfL) is a promising biomarker for neuromyelitis optica spectrum disorders (NMOSD) and multiple sclerosis (MS), but there is limited validation data in specific ethnic and disease groups. OBJECTIVE: To investigate the levels of sNfL in a cohort of Chinese patients with NMOSD and compare sNfL levels in patients with different disease courses and treatments. METHODS: We analysed sNfL levels in 153 Chinese patients with NMOSD (n = 51) and MS (n = 102) using single-molecule array (Simoa) technology. The sNfL levels were compared with those of 71 healthy controls from two centres in southern China. For each disease, we assessed correlations between sNfL and disease phases and treatments. RESULTS: Higher levels of sNfL were found in the patients with NMOSD [17.97 (10.55-27.94) pg/mL] and MS [15.83 (8.92-25.67) pg/mL] compared to healthy controls [10.09 (7.19-13.29) pg/mL, p < 0.001]. No significant differences were found between the AQP4-IgG-positive NMOSD group and OCB-positive MS group. CONCLUSIONS: sNfL measured by Simoa technology is a potential candidate blood biomarker for the diagnosis and disease monitoring of NMOSD in Chinese patients, warranting further prospective and multicentre studies.


Assuntos
Biomarcadores/sangue , Proteínas de Neurofilamentos/sangue , Neuromielite Óptica/sangue , Adulto , Aquaporina 4/imunologia , Povo Asiático , China , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Esclerose Múltipla/imunologia , Neuromielite Óptica/imunologia , Bandas Oligoclonais/imunologia
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