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BACKGROUND: The purpose of this study was to investigate the association between the mean upper cervical spinal cord cross-sectional area (MUCCA) and the risk and severity of cerebral small vessel disease (CSVD). METHODS: Community-dwelling residents in Lishui City, China, from the cross-sectional survey in the PRECISE cohort study (Polyvascular Evaluation for Cognitive Impairment and Vascular Events) conducted from 2017 to 2019. We included 1644 of 3067 community-dwelling adults in the PRECISE study after excluding those with incorrect, incomplete, insufficient, or missing clinical or imaging data. Total and modified total CSVD scores, as well as magnetic resonance imaging features, including white matter hyperintensity, lacunes, cerebral microbleeds, enlarged perivascular spaces, and brain atrophy, were assessed at the baseline. The Spinal Cord Toolbox was used to measure the upper cervical spinal cord cross-sectional area of the C1 to C3 segments of the spinal cord and its average value was taken as MUCCA. Participants were divided into 4 groups according to quartiles of MUCCA. Associations were analyzed using linear regression models adjusted for age, sex, current smoking and drinking, medical history, intracranial volume, and total cortical volume. RESULTS: The means±SD age of the participants was 61.4±6.5 years, and 635 of 1644 participants (38.6%) were men. The MUCCA was smaller in patients with CSVD than those without CSVD. Using the total CSVD score as a criterion, the MUCCA was 61.78±6.12 cm2 in 504 of 1644 participants with CSVD and 62.74±5.94 cm2 in 1140 of 1644 participants without CSVD. Using the modified total CSVD score, the MUCCA was 61.81±6.04 cm2 in 699 of 1644 participants with CSVD and 62.91±5.94 cm2 in 945 of 1644 without CSVD. There were statistical differences between the 2 groups after adjusting for covariates in 3 models. The MUCCA was negatively associated with the total and modified total CSVD scores (adjusted ß value, -0.009 [95% CI, -0.01 to -0.003] and -0.007 [95% CI, -0.01 to -0.0006]) after adjustment for covariates. Furthermore, the MUCCA was negatively associated with the white matter hyperintensity burden (adjusted ß value, -0.01 [95% CI, -0.02 to -0.003]), enlarged perivascular spaces in the basal ganglia (adjusted ß value, -0.005 [95% CI, -0.009 to -0.001]), lacunes (adjusted ß value, -0.004 [95% CI, -0.007 to -0.0007]), and brain atrophy (adjusted ß value, -0.009 [95% CI, -0.01 to -0.004]). CONCLUSIONS: The MUCCA and CSVD were correlated. Spinal cord atrophy may serve as an imaging marker for CSVD; thus, small vessel disease may involve the spinal cord in addition to being intracranial.
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Doenças de Pequenos Vasos Cerebrais , Medula Cervical , Masculino , Adulto , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Estudos de Coortes , Medula Cervical/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/epidemiologia , Doenças de Pequenos Vasos Cerebrais/complicações , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Atrofia/patologiaRESUMO
The network nature of the brain is gradually becoming a consensus in the neuroscience field. A set of highly connected regions in the brain network called "rich-club" are crucial high efficiency communication hubs in the brain. The abnormal rich-club organization can reflect underlying abnormal brain function and metabolism, which receives increasing attention. Diabetes is one of the risk factors for neurological diseases, and most individuals with prediabetes will develop overt diabetes within their lifetime. However, the gradual impact of hyperglycemia on brain structures, including rich-club organization, remains unclear. We hypothesized that the brain follows a special disrupted pattern of rich-club organization in prediabetes and diabetes. We used cross-sectional baseline data from the population-based PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events (PRECISE) study, which included 2218 participants with a mean age of 61.3 ± 6.6 years and 54.1% females comprising 1205 prediabetes, 504 diabetes, and 509 normal control subjects. The rich-club organization and network properties of the structural networks derived from diffusion tensor imaging data were investigated using a graph theory approach. Linear mixed models were used to assess associations between rich-club organization disruptions and the subjects' glucose status. Based on the graphical analysis methods, we observed the disrupted pattern of rich-club organization was from peripheral regions mainly located in frontal areas to rich-club regions mainly located in subcortical areas from prediabetes to diabetes. The rich-club organization disruptions were associated with elevated glucose levels. These findings provided more details of the process by which hyperglycemia affects the brain, contributing to a better understanding of the potential neurological consequences. Furthermore, the disrupted pattern observed in rich-club organization may serve as a potential neuroimaging marker for early detection and monitoring of neurological disorders in individuals with prediabetes or diabetes.
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Conectoma , Hiperglicemia , Estado Pré-Diabético , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Masculino , Imagem de Tensor de Difusão/métodos , Estado Pré-Diabético/diagnóstico por imagem , Estudos Transversais , Encéfalo/diagnóstico por imagem , Glucose , Vias NeuraisRESUMO
OBJECTIVES: To evaluate the feasibility of 0.2-mm isotropic lenticulostriate arteries (LSAs) imaging using compressed sensing time-of-flight (CS TOF) at around 10 min on 7T, and compare the delineation and characterization of LSAs using conventional TOF and CS TOF. METHODS: Thirty healthy volunteers were examined with CS TOF and conventional TOF at 7T for around 10 min each. CS TOF was optimized to achieve 0.2-mm isotropic LSA imaging. The numbers of LSA stems and branches were counted and compared on a vascular skeleton. The length and distance were measured and compared on the most prominent branch in each hemisphere. Another patient with intracranial artery stenosis was studied to compare LSA delineation in CS TOF and digital subtraction angiography (DSA). RESULTS: The number of stems visualized with CS TOF was significantly higher than with conventional TOF in both left (p = 0.002, ICC = 0.884) and right (p < 0.001, ICC = 0.938) hemispheres. The number of branches visualized by conventional TOF was significantly lower than that by CS TOF in both left (p < 0.001, ICC = 0.893) and right (p < 0.001, ICC = 0.896) hemispheres. The lengths were statistically higher in CS TOF than in conventional TOF (left: p < 0.001, ICC = 0.868; right: p < 0.001, ICC = 0.876). CONCLUSIONS: The high-resolution CS TOF improves the delineation and characterization of LSAs over conventional TOF. High-resolution LSA imaging using CS TOF can be a promising tool for clinical research and applications in patients with neurologic diseases. KEY POINTS: ⢠0.2-mm isotropic LSA imaging for around 10 min using CS TOF at 7T is feasible. ⢠More stems and branches of LSAs with longer lengths can be delineated with CS TOF than with conventional TOF at the same scan time. ⢠High-resolution CS TOF can be a promising tool for research and applications on LSA.
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Angiografia por Ressonância Magnética , Doenças Vasculares , Humanos , Angiografia por Ressonância Magnética/métodos , Artéria Cerebral Média , Artérias Cerebrais , Imageamento TridimensionalRESUMO
Previous research has linked specific modifiable lifestyle factors to age-related cognitive decline in adults. Little is known about the potential role of an overall healthy lifestyle in brain structure. We examined the association of adherence to a healthy lifestyle with a panel of brain structural markers among 2,413 participants in PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events (PRECISE) study in China and 19,822 participants in UK Biobank (UKB). A healthy lifestyle score (0-5) was constructed based on five modifiable lifestyle factors: diet, physical activity, smoking, alcohol consumption, and body mass index. Validated multimodal neuroimaging markers were derived from brain magnetic resonance imaging. In the cross-sectional analysis of PRECISE, participants who adopted four or five low-risk lifestyle factors had larger total brain volume (TBV; ß = 0.12, 95% CI: - 0.02, 0.26; p-trend = 0.05) and gray matter volume (GMV; ß = 0.16, 95% CI: 0.01, 0.30; p-trend = 0.05), smaller white matter hyperintensity volume (WMHV; ß = - 0.35, 95% CI: - 0.50, - 0.20; p-trend < 0.001) and lower odds of lacune (Odds Ratio [OR] = 0.48, 95% CI: 0.22, 1.08; p-trend = 0.03), compared to those with zero or one low-risk factors. Meanwhile, in the prospective analysis in UKB (with a median of 7.7 years' follow-up), similar associations were observed between the number of low-risk lifestyle factors (4-5 vs. 0-1) and TBV (ß = 0.22, 95% CI: 0.16, 0.28; p-trend < 0.001), GMV (ß = 0.26, 95% CI: 0.21, 0.32; p-trend < 0.001), white matter volume (WMV; ß = 0.08, 95% CI: 0.01, 0.15; p-trend = 0.001), hippocampus volume (ß = 0.15, 95% CI: 0.08, 0.22; p-trend < 0.001), and WMHV burden (ß = - 0.23, 95% CI: - 0.29, - 0.17; p-trend < 0.001). Those with four or five low-risk lifestyle factors showed approximately 2.0-5.8 years of delay in aging of brain structure. Adherence to a healthier lifestyle was associated with a lower degree of neurodegeneration-related brain structural markers in middle-aged and older adults.
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Envelhecimento , Encéfalo , Estilo de Vida Saudável , Idoso , Humanos , Pessoa de Meia-Idade , Encéfalo/diagnóstico por imagem , Estudos Transversais , Imageamento por Ressonância Magnética , Fatores de RiscoRESUMO
White matter hyperintensities (WMHs) represent the most common neuroimaging marker of cerebral small vessel disease (CSVD). The volume and location of WMHs are important clinical measures. We present a pipeline using deep fully convolutional network and ensemble models, combining U-Net, SE-Net, and multi-scale features, to automatically segment WMHs and estimate their volumes and locations. We evaluated our method in two datasets: a clinical routine dataset comprising 60 patients (selected from Chinese National Stroke Registry, CNSR) and a research dataset composed of 60 patients (selected from MICCAI WMH Challenge, MWC). The performance of our pipeline was compared with four freely available methods: LGA, LPA, UBO detector, and U-Net, in terms of a variety of metrics. Additionally, to access the model generalization ability, another research dataset comprising 40 patients (from Older Australian Twins Study and Sydney Memory and Aging Study, OSM), was selected and tested. The pipeline achieved the best performance in both research dataset and the clinical routine dataset with DSC being significantly higher than other methods (p < .001), reaching .833 and .783, respectively. The results of model generalization ability showed that the model trained on the research dataset (DSC = 0.736) performed higher than that trained on the clinical dataset (DSC = 0.622). Our method outperformed widely used pipelines in WMHs segmentation. This system could generate both image and text outputs for whole brain, lobar and anatomical automatic labeling WMHs. Additionally, software and models of our method are made publicly available at https://www.nitrc.org/projects/what_v1.
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Leucoaraiose/diagnóstico por imagem , Leucoaraiose/patologia , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação , Neuroimagem/métodos , Idoso , Conjuntos de Dados como Assunto , Humanos , Imageamento por Ressonância Magnética/normas , Neuroimagem/normasRESUMO
An automated experiment in multimodal imaging to probe structural, chemical, and functional behaviors in complex materials and elucidate the dominant physical mechanisms that control device function is developed and implemented. Here, the emergence of non-linear electromechanical responses in piezoresponse force microscopy (PFM) is explored. Non-linear responses in PFM can originate from multiple mechanisms, including intrinsic material responses often controlled by domain structure, surface topography that affects the mechanical phenomena at the tip-surface junction, and the presence of surface contaminants. Using an automated experiment to probe the origins of non-linear behavior in ferroelectric lead titanate (PTO) and ferroelectric Al0.93 B0.07 N films, it is found that PTO shows asymmetric nonlinear behavior across a/c domain walls and a broadened high nonlinear response region around c/c domain walls. In contrast, for Al0.93 B0.07 N, well-poled regions show high linear piezoelectric responses, when paired with low non-linear responses regions that are multidomain show low linear responses and high nonlinear responses. It is shown that formulating dissimilar exploration strategies in deep kernel learning as alternative hypotheses allows for establishing the preponderant physical mechanisms behind the non-linear behaviors, suggesting that automated experiments can potentially discern between competing physical mechanisms. This technique can also be extended to electron, probe, and chemical imaging.
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Multiplicative degree-Kirchhoff index is a very interesting topological index. In this article, we compute analytical expression for the expected value of the Multiplicative degree-Kirchhoff index in a random polygonal. Based on the result above, we also get the Multiplicative degree-Kirchhoff index of all polygonal chains with extremal values and average values.
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(K0.5 Na0.5 )NbO3 (KNN) is a promising lead-free alternative for ferroelectric thin films such as Pb(Zr,Ti)O3 . One main drawback is its high leakage current density at high electric fields, which has been previously linked to alkali non-stoichiometry. This paper compares three acetate-based chemical solution synthesis and deposition methods for 0.5â mol % Mn-doped KNN film fabrication, using lower crystallization temperature processes in comparison to the sintering temperatures necessary for fabrication of KNN ceramics. This paper shows the crucial role of the A site homogenization step during solution synthesis in preserving alkali chemical homogeneity of Mn doped KNN films. Chemically homogeneous films show a uniform grain size of 80â nm and a leakage current density under 2.8×10-8 â A cm-2 up to electric fields as high as 600â kV cm-1 , which is the highest breakdown strength reported for KNN thin films. Solution synthesis involving two-step pyrolysis resulted in films with dense, columnar microstructures, which are interesting for orientation control and enhancement of piezoelectric properties. This study reports detailed solution synthesis and deposition processes with good dielectric, ferroelectric and breakdown field properties. An optimized fabrication method that should couple low leakage current density with dense and oriented microstructures is proposed.
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Infarto Cerebral , Ataque Isquêmico Transitório , AVC Isquêmico , Imageamento por Ressonância Magnética , Humanos , Ataque Isquêmico Transitório/diagnóstico por imagem , AVC Isquêmico/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Infarto Cerebral/diagnóstico por imagem , Masculino , Feminino , Idoso , Pessoa de Meia-IdadeRESUMO
We present 'UBO Detector', a cluster-based, fully automated pipeline for extracting and calculating variables for regions of white matter hyperintensities (WMH) (available for download at https://cheba.unsw.edu.au/group/neuroimaging-pipeline). It takes T1-weighted and fluid attenuated inversion recovery (FLAIR) scans as input, and SPM12 and FSL functions are utilised for pre-processing. The candidate clusters are then generated by FMRIB's Automated Segmentation Tool (FAST). A supervised machine learning algorithm, k-nearest neighbor (k-NN), is applied to determine whether the candidate clusters are WMH or non-WMH. UBO Detector generates both image and text (volumes and the number of WMH clusters) outputs for whole brain, periventricular, deep, and lobar WMH, as well as WMH in arterial territories. The computation time for each brain is approximately 15â¯min. We validated the performance of UBO Detector by showing a) high segmentation (similarity index (SI)â¯=â¯0.848) and volumetric (intraclass correlation coefficient (ICC)â¯=â¯0.985) agreement between the UBO Detector-derived and manually traced WMH; b) highly correlated (r2â¯>â¯0.9) and a steady increase of WMH volumes over time; and c) significant associations of periventricular (tâ¯=â¯22.591, pâ¯<â¯0.001) and deep (tâ¯=â¯14.523, pâ¯<â¯0.001) WMH volumes generated by UBO Detector with Fazekas rating scores. With parallel computing enabled in UBO Detector, the processing can take advantage of multi-core CPU's that are commonly available on workstations. In conclusion, UBO Detector is a reliable, efficient and fully automated WMH segmentation pipeline.
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Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Processamento de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Idoso , Algoritmos , Análise por Conglomerados , Estudos Transversais , Feminino , Humanos , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos , Masculino , SoftwareRESUMO
Sulcal morphology has been reported to change with age-related neurological diseases, but the trajectories of sulcal change in normal ageing in the elderly is still unclear. We conducted a study of sulcal morphological changes over seven years in 132 normal elderly participants aged 70-90 years at baseline, and who remained cognitively normal for the next seven years. We examined the fold opening and sulcal depth of sixteen (eight on each hemisphere) prominent sulci based on T1-weighted MRI using automated methods with visual quality control. The trajectory of each individual sulcus with respect to age was examined separately by linear mixed models. Fold opening was best modelled by cubic fits in five sulci, by quadratic models in six sulci and by linear models in five sulci, indicating an accelerated widening of a number of sulci in older age. Sulcal depth showed significant linear decline in three sulci and quadratic trend in one sulcus. Turning points of non-linear trajectories towards accelerated widening of the fold were found to be around the age between 75 and 80, indicating an accelerated atrophy of brain cortex starting in the age of late 70s. Our findings of cortical sulcal changes in normal ageing could provide a reference for studies of neurocognitive disorders, including neurodegenerative diseases, in the elderly.
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Envelhecimento/patologia , Córtex Cerebral/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Atrofia/patologia , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , MasculinoRESUMO
RATIONALE: Intimal calcification is highly correlated with atherosclerotic plaque burden, but the underlying mechanism is poorly understood. We recently reported that cartilage oligomeric matrix protein (COMP), a component of vascular extracellular matrix, is an endogenous inhibitor of vascular smooth muscle cell calcification. OBJECTIVE: To investigate whether COMP affects atherosclerotic calcification. METHODS AND RESULTS: ApoE(-/-)COMP(-/-) mice fed with chow diet for 12 months manifested more extensive atherosclerotic calcification in the innominate arteries than did ApoE(-/-) mice. To investigate which origins of COMP contributed to atherosclerotic calcification, bone marrow transplantation was performed between ApoE(-/-) and ApoE(-/-)COMP(-/-) mice. Enhanced calcification was observed in mice transplanted with ApoE(-/-)COMP(-/-) bone marrow compared with mice transplanted with ApoE(-/-) bone marrow, indicating that bone marrow-derived COMP may play a critical role in atherosclerotic calcification. Furthermore, microarray profiling of wild-type and COMP(-/-) macrophages revealed that COMP-deficient macrophages exerted atherogenic and osteogenic characters. Integrin ß3 protein was attenuated in COMP(-/-) macrophages, and overexpression of integrin ß3 inhibited the shift of macrophage phenotypes by COMP deficiency. Furthermore, adeno-associated virus 2-integrin ß3 infection attenuated atherosclerotic calcification in ApoE(-/-)COMP(-/-) mice. Mechanistically, COMP bound directly to ß-tail domain of integrin ß3 via its C-terminus, and blocking of the COMP-integrin ß3 association by ß-tail domain mimicked the COMP deficiency-induced shift in macrophage phenotypes. Similar to COMP deficiency in mice, transduction of adeno-associated virus 2-ß-tail domain enhanced atherosclerotic calcification in ApoE(-/-) mice. CONCLUSIONS: These results reveal that COMP deficiency acted via integrin ß3 to drive macrophages toward the atherogenic and osteogenic phenotype and thereby aggravate atherosclerotic calcification.
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Aterosclerose/metabolismo , Proteína de Matriz Oligomérica de Cartilagem/deficiência , Macrófagos/fisiologia , Fenótipo , Calcificação Vascular/metabolismo , Animais , Aterosclerose/genética , Aterosclerose/patologia , Proteína de Matriz Oligomérica de Cartilagem/genética , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Calcificação Vascular/genética , Calcificação Vascular/patologiaRESUMO
BACKGROUND & AIMS: Cross-sectional studies have shown that apolipoprotein B (apoB) is positively associated with the prevalence of non-alcoholic fatty liver disease (NAFLD). This study aimed to investigate the prospective relationship between the serum apoB levels and the development of NAFLD in a Chinese population. METHODS: A cohort of 7077 initially NAFLD-free participants was enrolled in this prospectively study. The incidence of NAFLD was calculated among participants with different baseline serum apoB quintiles. Cox proportional hazards regression analyses were conducted to calculate the risks for incident NAFLD. RESULTS: During 41 555 person-year follow-ups, 1139 incident NAFLD cases were identified. The baseline apoB levels were linear and positively correlated with NAFLD incidence. The incidence was 16.99, 22.63, 24.73, 37.51 and 42.77 per 1000 person-year follow-up for participants with baseline apoB levels in quintiles 1-5, respectively. Compared with participants with baseline apoB levels in quintile 1, the hazard ratios (95% confidence interval) for incident NAFLD were 1.353 (1.100-1.663), 1.482 (1.207-1.820), 2.232 (1.832-2.720) and 2.543 (2.082-3.106) for participants with baseline apoB levels in quintile 2-5, respectively. The hazard ratios were attenuated but remained statistically significant after adjusting for age, gender, body mass index and variables associated with metabolic syndrome. CONCLUSION: Elevated serum apoB levels independently predict an increased risk for incident NAFLD.
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Apolipoproteína B-100/sangue , Hepatopatia Gordurosa não Alcoólica/sangue , Adulto , China , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de RiscoRESUMO
Chemokines and their receptors have been implicated in cell migration and metastasis of multiple malignant tumors. But the function of CXCR6 signaling in gastric cancer is not comprehensively understood. In the present study, we hypothesized that CXCR6 signaling might play an essential role in the progression of gastric cancer. The expression of CXCR6 was examined by immunohistochemical assay in human gastric cancer, and lentivirus-mediated CXCR6 knockdown by shRNA (Lv-shCXCR6) was used for investigating cell migration and invasion indicated by Wound-healing and Transwell assays. Consequently, the expression level of CXCR6 was increased in gastric cancer compared with the adjacent non-tumor tissues (54.2% vs. 27.1%, P = 0.006), and was closely associated with the metastatic lymph node in gastric cancer (P = 0.021). Furthermore, blockade of the CXCR6 signaling reduced the migration and invasion of gastric cancer cells followed by decreased expression of AKT, MMP-2, and MMP-9. In conclusion, these findings demonstrate that CXCR6 may promote the development of gastric cancer cells through regulation of AKT signaling.
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Antineoplásicos/farmacologia , Movimento Celular/efeitos dos fármacos , Invasividade Neoplásica/prevenção & controle , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Quimiocinas/antagonistas & inibidores , Receptores Virais/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Progressão da Doença , Feminino , Humanos , Lentivirus/metabolismo , Metástase Linfática/patologia , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , RNA Interferente Pequeno/metabolismo , Receptores CXCR6 , Receptores de Quimiocinas/metabolismoRESUMO
Most previous neuroimaging studies of age-related brain structural changes in older individuals have been cross-sectional and/or restricted to clinical samples. The present study of 345 community-dwelling non-demented individuals aged 70-90years aimed to examine age-related brain volumetric changes over two years. T1-weighted magnetic resonance imaging scans were obtained at baseline and at 2-year follow-up and analyzed using the FMRIB Software Library and FreeSurfer to investigate cortical thickness and shape and volumetric changes of subcortical structures. The results showed significant atrophy across much of the cerebral cortex with bilateral transverse temporal regions shrinking the fastest. Atrophy was also found in a number of subcortical structures, including the CA1 and subiculum subfields of the hippocampus. In some regions, such as left and right entorhinal cortices, right hippocampus and right precentral area, the rate of atrophy increased with age. Our analysis also showed that rostral middle frontal regions were thicker bilaterally in older participants, which may indicate its ability to compensate for medial temporal lobe atrophy. Compared to men, women had thicker cortical regions but greater rates of cortical atrophy. Women also had smaller subcortical structures. A longer period of education was associated with greater thickness in a number of cortical regions. Our results suggest a pattern of brain atrophy with non-demented people that resembles a less extreme form of the changes associated with Alzheimer's disease (AD).
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Envelhecimento/patologia , Encéfalo/patologia , Córtex Cerebral/patologia , Idoso , Idoso de 80 Anos ou mais , Atrofia/patologia , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Fatores SexuaisRESUMO
BACKGROUND: The purpose of this study was to explore the specific regions of abnormal cortical communication efficiency in patients with mild subcortical stroke and to investigate the relationship between these communication efficiency abnormalities and multidimensional cognition. METHODS: The research involved 35 patients with mild strokes affecting the basal ganglia and 29 healthy controls (HC). Comprehensive neuroimaging and neuropsychological assessments were conducted. Stroke patients were categorized into post-stroke cognitive impairment (PSCI) (MoCA ≤ 22) and non-cognitively impaired stroke patients (NPSCI) (MoCA ≥ 23) based on their cognitive performance. Additionally, 22 patients were reassessed three months later. RESULTS: PSCI patients, compared to HC and NPSCI groups, had significantly higher communication efficiency in specific brain regions. A notable finding was the significant correlation between increased communication efficiency in the medioventral occipital cortex and multidimensional cognitive decline. However, this increased communication efficiency in PSCI patients lessened during the three-month follow-up period. CONCLUSIONS: the heightened communication efficiency in the medio-ventral occipital cortex may represent a compensatory mechanism for cognitive impairment in PSCI patients, which undergoes adjustment three months after stroke.
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BACKGROUND: This study aimed to investigate the relationship between overall obesity, central obesity and brain volumes, as well as to determine the extent to which cardiometabolic and inflammatory measures act as mediators in the association between body mass index (BMI), waist-hip ratio (WHR) and brain volumes. METHODS: In the context of counterfactual framework, mediation analysis was used to explore the potential mediation in which cardiometabolic and inflammatory measures may mediate the relationship between BMI, WHR, and brain volumes. RESULTS: Among 2413 community-dwelling participants, those with high BMI or WHR levels experienced an approximately brain ageing of 4 years. Especially, individuals with high WHR or BMI under the age of 65 exhibited white matter hyperintensity volume (WMHV) differences equivalent to around 5 years of ageing. Conversely, in the high-level WHR population over the age of 65, premature brain ageing in gray matter volume (GMV) exceeded 4.5 years. For GMV, more than 45% of the observed effect of WHR was mediated by glycaemic metabolism indicators. This proportion increases to 78.70% when blood pressure, triglyceride, leucocyte count, and neutrophil count are jointly considered with glycaemic metabolism indicators. Regarding WHR and BMI's association with WMHV, cardiometabolic and inflammatory indicators, along with high-density lipoprotein cholesterol, mediated 35.50% and 20.20% of the respective effects. CONCLUSIONS: Overall obesity and central obesity were associated with lower GMV and higher WMHV, a process that is partially mediated by the presence of cardiometabolic and inflammatory measures.
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Brain aging is typically associated with a significant decline in cognitive performance. Vascular risk factors (VRF) and subsequent atherosclerosis (AS) play a major role in this process. Brain resilience reflects the brain's ability to withstand external perturbations, but the relationship of brain resilience with cognition during the aging process remains unclear. Here, we investigated how brain topological resilience (BTR) is associated with cognitive performance in the face of aging and vascular risk factors. We used data from two cross-ethnicity community cohorts, PolyvasculaR Evaluation for Cognitive Impairment and Vascular Events (PRECISE, n = 2220) and Sydney Memory and Ageing Study (MAS, n = 246). We conducted an attack simulation on brain structural networks based on k-shell decomposition and node degree centrality. BTR was defined based on changes in the size of the largest subgroup of the network during the simulation process. Subsequently, we explored the negative correlations of BTR with age, VRF, and AS, and its positive correlation with cognitive performance. Furthermore, using structural equation modeling (SEM), we constructed path models to analyze the directional dependencies among these variables, demonstrating that aging, AS, and VRF affect cognition by disrupting BTR. Our results also indicated the specificity of this metric, independent of brain volume. Overall, these findings underscore the supportive role of BTR on cognition during aging and highlight its potential application as an imaging marker for objective assessment of brain cognitive performance.
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BACKGROUND AND OBJECTIVES: Noninvasive and accurate biomarkers of neurologic Wilson disease (NWD), a rare inherited disorder, could reduce diagnostic error or delay. Excessive subcortical metal deposition seen on susceptibility imaging has suggested a characteristic pattern in NWD. With submillimeter spatial resolution and increased contrast, 7T susceptibility-weighted imaging (SWI) may enable better visualization of metal deposition in NWD. In this study, we sought to identify a distinctive metal deposition pattern in NWD using 7T SWI and investigate its diagnostic value and underlying pathophysiologic mechanism. METHODS: Patients with WD, healthy participants with monoallelic ATP7B variant(s) on a single chromosome, and health controls (HCs) were recruited. NWD and non-NWD (nNWD) were defined according to the presence or absence of neurologic symptoms during investigation. Patients with other diseases with comparable clinical or imaging manifestations, including early-onset Parkinson disease (EOPD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and neurodegeneration with brain iron accumulation (NBIA), were additionally recruited and assessed for exploratory comparative analysis. All participants underwent 7T T1, T2, and high-resolution SWI scanning. Quantitative susceptibility mapping and principal component analysis were performed to illustrate metal distribution. RESULTS: We identified a linear signal intensity change consisting of a hyperintense strip at the lateral border of the globus pallidus in patients with NWD. We termed this feature "hyperintense globus pallidus rim sign." This feature was detected in 38 of 41 patients with NWD and was negative in all 31 nNWD patients, 15 patients with EOPD, 30 patients with MSA, 15 patients with PSP, and 12 patients with NBIA; 22 monoallelic ATP7B variant carriers; and 41 HC. Its sensitivity to differentiate between NWD and HC was 92.7%, and specificity was 100%. Severity of the hyperintense globus pallidus rim sign measured by a semiquantitative scale was positively correlated with neurologic severity (ρ = 0.682, 95% CI 0.467-0.821, p < 0.001). Patients with NWD showed increased susceptibility in the lenticular nucleus with high regional weights in the lateral globus pallidus and medial putamen. DISCUSSION: The hyperintense globus pallidus rim sign showed high sensitivity and excellent specificity for diagnosis and differential diagnosis of NWD. It is related to a special metal deposition pattern in the lenticular nucleus in NWD and can be considered as a novel neuroimaging biomarker of NWD. CLASSIFICATION OF EVIDENCE: The study provides Class II evidence that the hyperintense globus pallidus rim sign on 7T SWI MRI can accurately diagnose neurologic WD.
Assuntos
Degeneração Hepatolenticular , Imageamento por Ressonância Magnética , Humanos , Degeneração Hepatolenticular/diagnóstico por imagem , Degeneração Hepatolenticular/metabolismo , Feminino , Masculino , Adulto , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Adulto Jovem , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , ATPases Transportadoras de Cobre/metabolismo , ATPases Transportadoras de Cobre/genética , Cobre/metabolismo , Adolescente , Globo Pálido/diagnóstico por imagem , Globo Pálido/metabolismoRESUMO
Measuring the geometry or morphology of sulcal folds has recently become an important approach to investigating neuroanatomy. However, relationships between cortical sulci and other brain structures are poorly understood. The present study investigates how age-related changes in sulcal width are associated with age-related changes in traditional indices of brain structure such as cortical thickness, and cortical gray matter (GM), white matter (WM), subcortical, and white matter hyperintensity (WMH) volumes. These indices and sulcal width were measured at baseline and at two-year follow up in 185 community-dwelling individuals (91 men) aged 70-89 years. There were significant increases in sulcal width and WMH volume, and significant decreases in all other indices between baseline and follow-up. Sulcal widening was associated with decreases in cortical GM, subcortical and WM volumes. A further association between sulcal width and cortical thickness became non-significant when cortical GM volume was controlled for. Our findings give insights into the mechanisms responsible for cortical sulcal morphology. The relationships between sulcal morphology and other common measures suggest that it could be a more comprehensive measure for clinical classifications than traditional neuroimaging metrics, such as cortical thickness.