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1.
Ann Neurol ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888141

RESUMO

OBJECTIVE: Patients with Lewy body diseases have an increased risk of dementia, which is a significant predictor for survival. Posterior cortical hypometabolism on [18F]fluorodeoxyglucose positron emission tomography (PET) precedes the development of dementia by years. We therefore examined the prognostic value of cerebral glucose metabolism for survival. METHODS: We enrolled patients diagnosed with Parkinson's disease (PD), Parkinson's disease with dementia, or dementia with Lewy bodies who underwent [18F]fluorodeoxyglucose PET. Regional cerebral metabolism of each patient was analyzed by determining the expression of the PD-related cognitive pattern (Z-score) and by visual PET rating. We analyzed the predictive value of PET for overall survival using Cox regression analyses (age- and sex-corrected) and calculated prognostic indices for the best model. RESULTS: Glucose metabolism was a significant predictor of survival in 259 included patients (n = 118 events; hazard ratio: 1.4 [1.2-1.6] per Z-score; hazard ratio: 1.8 [1.5-2.2] per visual PET rating score; both p < 0.0001). Risk stratification with visual PET rating scores yielded a median survival of 4.8, 6.8, and 12.9 years for patients with severe, moderate, and mild posterior cortical hypometabolism (median survival not reached for normal cortical metabolism). Stratification into 5 groups based on the prognostic index revealed 10-year survival rates of 94.1%, 78.3%, 34.7%, 0.0%, and 0.0%. INTERPRETATION: Regional cerebral glucose metabolism is a significant predictor of survival in Lewy body diseases and may allow an earlier survival prediction than the clinical milestone "dementia." Thus, [18F]fluorodeoxyglucose PET may improve the basis for therapy decisions, especially for invasive therapeutic procedures like deep brain stimulation in Parkinson's disease. ANN NEUROL 2024.

2.
Ann Neurol ; 94(4): 684-695, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37376770

RESUMO

OBJECTIVE: The purpose of this study was to characterize a metabolic brain network associated with X-linked dystonia-parkinsonism (XDP). METHODS: Thirty right-handed Filipino men with XDP (age = 44.4 ± 8.5 years) and 30 XDP-causing mutation negative healthy men from the same population (age = 37.4 ± 10.5 years) underwent [18 F]-fluorodeoxyglucose positron emission tomography. Scans were analyzed using spatial covariance mapping to identify a significant XDP-related metabolic pattern (XDPRP). Patients were rated clinically at the time of imaging according to the XDP-Movement Disorder Society of the Philippines (MDSP) scale. RESULTS: We identified a significant XDPRP topography from 15 randomly selected subjects with XDP and 15 control subjects. This pattern was characterized by bilateral metabolic reductions in caudate/putamen, frontal operculum, and cingulate cortex, with relative increases in the bilateral somatosensory cortex and cerebellar vermis. Age-corrected expression of XDPRP was significantly elevated (p < 0.0001) in XDP compared to controls in the derivation set and in the remaining 15 patients (testing set). We validated the XDPRP topography by identifying a similar pattern in the original testing set (r = 0.90, p < 0.0001; voxel-wise correlation between both patterns). Significant correlations between XDPRP expression and clinical ratings for parkinsonism-but not dystonia-were observed in both XDP groups. Further network analysis revealed abnormalities of information transfer through the XDPRP space, with loss of normal connectivity and gain of abnormal functional connections linking network nodes with outside brain regions. INTERPRETATION: XDP is associated with a characteristic metabolic network associated with abnormal functional connectivity among the basal ganglia, thalamus, motor regions, and cerebellum. Clinical signs may relate to faulty information transfer through the network to outside brain regions. ANN NEUROL 2023;94:684-695.


Assuntos
Distonia , Distúrbios Distônicos , Doenças Genéticas Ligadas ao Cromossomo X , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Distúrbios Distônicos/diagnóstico por imagem , Distúrbios Distônicos/genética , Distúrbios Distônicos/complicações , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico por imagem , Doenças Genéticas Ligadas ao Cromossomo X/genética , Distonia/diagnóstico por imagem , Distonia/genética , Biomarcadores
3.
Inorg Chem ; 63(1): 353-368, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38113182

RESUMO

Combining magnetic and dielectric materials to form a composite can significantly improve its impedance matching and electromagnetic wave absorption performance. Furthermore, composite materials with a core-shell structure hold promise in meeting the demand for lightweight and highly electromagnetic-absorbing properties. In this study, uniform hexagonal flake barium ferrite (BaFe12O19) was prepared using the hydrothermal method. Subsequently, BaFe12O19@PVDF composites were synthesized by the sol-gel method. By adjusting the mass ratio of BaFe12O19 and PVDF, the shell size of the BaFe12O19@PVDF composite material was controlled, and its electromagnetic absorption performance was enhanced. The shell thickness of BaFe12O19@PVDF is 19.64 nm when the BaFe12O19: PVDF mass ratio is 1:1.0, and the optimal impedance matching is obtained at 13.4 GHz. Meanwhile, at a thickness of 1.5 mm, the minimum reflection loss (RLmin) reached -58.04 dB, and an effective absorption bandwidth (EAB) (RL ≤ -10 dB) of 5.53 GHz was achieved within the frequency range of 11.65 to 15.63 GHz and from 16.36 to 17.91 GHz. Besides, the composites with a matching thickness of 3.5 mm show a maximum EAB of 15.90 GHz when the mass ratio of BaFe12O19 to PVDF is 1:1.2. Within the frequency range of 2-18 GHz, the coverage of reflection loss less than -10 dB is 99.38%, almost achieving full coverage. These results demonstrate that BaFe12O19@PVDF composites exhibit excellent electromagnetic-absorbing performances, making them an excellent candidate for electromagnetic wave absorption in 5G communications.

4.
Inorg Chem ; 62(14): 5872-5879, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36978229

RESUMO

The d10 metal oxides with low effective mass and high mobility of photoexcited electrons have received much attention in photocatalytic water splitting. However, there are still challenges in practical application due to insufficient visible light absorption. Here, an unusual phenomenon of the In2+ cation in PtIn6(GeO4)2O and PtIn6(Ga/InO4)2 with a narrow band gap is systematically investigated using density functional theory calculations. According to chemical bond analysis, the final band edge structure results from the interaction between the empty In-5p orbitals and the occupied antibonding state of the In 5s-O 2p orbitals as well as the further hybridization of adjacent In cations in PtIn6 octahedrons. The unique bonding characteristic of In2+ cations endows them with a narrow band gap and visible light response ability. Moreover, the occupied antibonding state could weaken the strength of the In-O covalent bond and strengthen the orbital hybridization of the In-In bond, causing the conduction band minimum to be located in the electroactive In6 cavity. This work reveals the origin of the narrow band gap of PtIn6(GeO4)2O and PtIn6(Ga/InO4)2 in view of bond theory and shows that they are promising semiconductors for the application of photocatalytic H2 generation.

5.
Molecules ; 27(9)2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35566335

RESUMO

In order to improve the properties of wood flour (WF)/poly(lactic acid) (PLA) 3D-printed composites, WF was treated with a silane coupling agent (KH550) and acetic anhydride (Ac2O), respectively. The effects of WF modification and the addition of acrylicester resin (ACR) as a toughening agent on the flowability of WF/PLA composite filament and the mechanical, thermal, dynamic mechanical thermal and water absorption properties of fused deposition modeling (FDM) 3D-printed WF/PLA specimens were investigated. The results indicated that the melt index (MI) of the specimens decreased after WF pretreatment or the addition of ACR, while the die swell ratio increased; KH550-modified WF/PLA had greater tensile strength, tensile modulus and impact strength, while Ac2O-modified WF/PLA had greater tensile modulus, flexural strength, flexural modulus and impact strength than unmodified WF/PLA; after the addition of ACR, all the strengths and moduli of WF/PLA could be improved; after WF pretreatment or the addition of ACR, the thermal decomposition temperature, storage modulus and glass transition temperature of WF/PLA were all increased, and water absorption was reduced.


Assuntos
Farinha , Madeira , Poliésteres , Impressão Tridimensional , Água
6.
Eur J Neurol ; 28(9): 2927-2939, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34110063

RESUMO

BACKGROUND AND PURPOSE: The diagnosis and monitoring of semantic variant primary progressive aphasia (sv-PPA) are clinically challenging. We aimed to establish a distinctive metabolic pattern in sv-PPA for diagnosis and severity evaluation. METHODS: Fifteen sv-PPA patients and 15 controls were enrolled to identify sv-PPA-related pattern (sv-PPARP) by principal component analysis of 18 F-fluorodeoxyglucose positron emission tomography. Eighteen Alzheimer disease dementia (AD) and 14 behavioral variant frontotemporal dementia (bv-FTD) patients were enrolled to test the discriminatory power. Correspondingly, regional metabolic activities extracted from the voxelwise analysis were evaluated for the discriminatory power. RESULTS: The sv-PPARP was characterized as decreased metabolic activity mainly in the bilateral temporal lobe (left predominance), middle orbitofrontal gyrus, left hippocampus/parahippocampus gyrus, fusiform gyrus, insula, inferior orbitofrontal gyrus, and striatum, with increased activity in the bilateral lingual gyrus, cuneus, calcarine gyrus, and right precentral and postcentral gyrus. The pattern expression had significant discriminatory power (area under the curve [AUC] = 0.98, sensitivity = 100%, specificity = 94.4%) in distinguishing sv-PPA from AD, and the asymmetry index offered complementary discriminatory power (AUC = 0.91, sensitivity = 86.7%, specificity = 92.9%) in distinguishing sv-PPA from bv-FTD. In sv-PPA patients, the pattern expression correlated with Boston Naming Test scores at baseline and showed significant increase in the subset of patients with follow-up. The voxelwise analysis showed similar topography, and the regional metabolic activities had equivalent or better discriminatory power and clinical correlations with Boston Naming Test scores. The ability to reflect disease progression in longitudinal follow-up seemed to be inferior to the pattern expression. CONCLUSIONS: The sv-PPARP might serve as an objective biomarker for diagnosis and progression evaluation.


Assuntos
Doença de Alzheimer , Afasia Primária Progressiva , Demência Frontotemporal , Afasia Primária Progressiva/diagnóstico por imagem , Humanos , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Semântica
7.
Mov Disord ; 35(12): 2201-2210, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32853481

RESUMO

BACKGROUND: Alterations in the GBA gene (NM_000157.3) are the most important genetic risk factor for Parkinson's disease (PD). Biallelic GBA mutations cause the lysosomal storage disorder Gaucher's disease. The GBA variants p.E365K and p.T408M are associated with PD but not with Gaucher's disease. The pathophysiological role of these variants needs to be further explored. OBJECTIVE: This study analyzed clinical, neuropsychological, metabolic, and neuroimaging phenotypes of patients with PD carrying the GBA variants p.E365K and p.T408M. METHODS: GBA was sequenced in 56 patients with mid-stage PD. Carriers of GBA variants were compared with noncarriers regarding clinical history and symptoms, neuropsychological features, metabolomics, and multimodal neuroimaging. Blood plasma gas chromatography coupled to mass spectrometry, 6-[18 F]fluoro-L-Dopa positron emission tomography (PET), [18 F]fluorodeoxyglucose PET, and resting-state functional magnetic resonance imaging were performed. RESULTS: Sequence analysis detected 13 heterozygous GBA variant carriers (7 with p.E365K, 6 with p.T408M). One patient carried a GBA mutation (p.N409S) and was excluded. Clinical history and symptoms were not significantly different between groups. Global cognitive performance was lower in variant carriers. Metabolomic group differences were suggestive of more severe PD-related alterations in carriers versus noncarriers. Both PET scans showed signs of a more advanced disease; [18 F]fluorodeoxyglucose PET and functional magnetic resonance imaging showed similarities with Lewy body dementia and PD dementia in carriers. CONCLUSIONS: This is the first study to comprehensively assess (neuro-)biological phenotypes of GBA variants in PD. Metabolomics and neuroimaging detected more significant group differences than clinical and behavioral evaluation. These alterations could be promising to monitor effects of disease-modifying treatments targeting glucocerebrosidase metabolism. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , Glucosilceramidase/genética , Humanos , Metabolômica , Mutação/genética , Neuroimagem , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/genética , Fenótipo
8.
Mol Med ; 25(1): 24, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31146675

RESUMO

BACKGROUND: Alcohol abuse affects the brain regions responsible for memory, coordination and emotional processing. Binge alcohol drinking has shown reductions in brain activity, but the molecular targets have not been completely elucidated. We hypothesized that brain cells respond to excessive alcohol by releasing a novel inflammatory mediator, called cold inducible RNA-binding protein (CIRP), which is critical for the decreased brain metabolic activity and impaired cognition. METHODS: Male wild type (WT) mice and mice deficient in CIRP (CIRP-/-) were studied before and after exposure to binge alcohol level by assessment of relative brain glucose metabolism with fluorodeoxyglucose (18FDG) and positron emission tomography (PET). Mice were also examined for object-place memory (OPM) and open field (OF) tasks. RESULTS: Statistical Parametric Analysis (SPM) of 18FDG-PET uptake revealed marked decreases in relative glucose metabolism in distinct brain regions of WT mice after binge alcohol. Regional analysis (post hoc) revealed that while activity in the temporal (secondary visual) and limbic (entorhinal/perirhinal) cortices was decreased in WT mice, relative glucose metabolic activity was less suppressed in the CIRP-/- mice. Group and condition interaction analysis revealed differing responses in relative glucose metabolism (decrease in WT mice but increase in CIRP-/- mice) after alcohol in brain regions including the hippocampus and the cortical amygdala where the percent changes in metabolic activity correlated with changes in object discrimination performance. Behaviorally, alcohol-treated WT mice were impaired in exploring a repositioned object in the OPM task, and were more anxious in the OF task, whereas CIRP-/- mice were not impaired in these tasks. CONCLUSION: CIRP released from brain cells could be responsible for regional brain metabolic hypoactivity leading to cognitive impairment under binge alcohol conditions.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas/complicações , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Proteínas de Ligação a RNA/metabolismo , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Fluordesoxiglucose F18/análise , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Tomografia por Emissão de Pósitrons , Proteínas de Ligação a RNA/genética , Memória Espacial/efeitos dos fármacos
9.
Gastroenterology ; 155(2): 542-556, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29702115

RESUMO

BACKGROUND & AIMS: Single nucleotide polymorphisms could affect risk for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). We performed a germline copy number variation (CNV)-based genome-wide association study (GWAS) in populations of Chinese ancestry to search for germline CNVs that increase risk of HCC. METHODS: We conducted a CNV-based GWAS of 1583 HCC cases (persons with chronic HBV infection and HCC) and 1540 controls (persons with chronic HBV infection without HCC) in Chinese populations. Identified candidates were expressed in L-02, HepG2, or TP53-/- or wild-type HCT116 cells, and knocked down with short hairpin RNAs in HepG2, Bel-7402, and SMMC-7721 cells; proliferation, colony formation, and apoptosis were measured. Formation of xenograft tumors from cell lines was monitored in nude mice. Subcellular localization of ribosome proteins and levels or activity of p53 were investigated by co-immunoprecipitation, immunofluorescence, and immunoblot analyses. Levels of small nucleolar RNA H/ACA box 18-like 5 (SNORA18L5) were quantified by quantitative reverse transcription polymerase chain reaction. RESULTS: We identified a low-frequency duplication at chromosome 15q13.3 strongly associated with risk of HBV-related HCC (overall P = 3.17 × 10-8; odds ratio, 12.02). Copy numbers of the 15q13.3 duplication correlated with the expression of SNORA18L5 in liver tissues. Overexpression of SNORA18L5 increased HCC cell proliferation and growth of xenograft tumors in mice; knockdown reduced HCC proliferation and tumor growth. SNORA18L5 overexpression in HepG2 and SMMC-7721 cells inhibited p53-dependent cell cycle arrest and apoptosis. Overexpression of SNORA18L5 led to hyperactive ribosome biogenesis, increasing levels of mature 18S and 28S ribosomal RNAs and causing the ribosomal proteins RPL5 and RPL11 to stay in the nucleolus, which kept them from binding to MDM2. This resulted in increased MDM2-mediated ubiquitination and degradation of p53. Levels of SNORA18L5 were increased in HCC tissues compared with nontumor liver tissues and associated with shorter survival times of patients. CONCLUSIONS: In a CNV-based GWAS, we associated duplication at 15q13.3 with increased risk of HBV-related HCC. We found SNORA18L5 at this location to promote HCC cell proliferation and tumor growth in mice. SNORA18L5 increases ribosome biogenesis, facilitates ribosomal RNA maturation, and alters localization of RPL5 and RPL11, allowing for increased MDM2-mediated proteolysis of p53 and cell cycle arrest.


Assuntos
Carcinoma Hepatocelular/genética , Cromossomos Humanos Par 15/genética , Hepatite B Crônica/genética , Neoplasias Hepáticas/genética , RNA Nucleolar Pequeno/genética , Proteínas Ribossômicas/metabolismo , Proteína Supressora de Tumor p53/genética , Adulto , Animais , Povo Asiático/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Variações do Número de Cópias de DNA/genética , Feminino , Duplicação Gênica , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Estudo de Associação Genômica Ampla , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Humanos , Fígado/patologia , Fígado/virologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , RNA Interferente Pequeno/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Hum Brain Mapp ; 39(7): 2842-2858, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29536636

RESUMO

Progressive supranuclear palsy (PSP) is a rare movement disorder and often difficult to distinguish clinically from Parkinson's disease (PD) and multiple system atrophy (MSA) in early phases. In this study, we report reproducible disease-related topographies of brain network and regional glucose metabolism associated with PSP in clinically-confirmed independent cohorts of PSP, MSA, and PD patients and healthy controls in the USA and China. Using 18 F-FDG PET images from PSP and healthy subjects, we applied spatial covariance analysis with bootstrapping to identify a PSP-related pattern (PSPRP) and estimate its reliability, and evaluated the ability of network scores for differential diagnosis. We also detected regional metabolic differences using statistical parametric mapping analysis. We produced a highly reliable PSPRP characterized by relative metabolic decreases in the middle prefrontal cortex/cingulate, ventrolateral prefrontal cortex, striatum, thalamus and midbrain, covarying with relative metabolic increases in the hippocampus, insula and parieto-temporal regions. PSPRP network scores correlated positively with PSP duration and accurately discriminated between healthy, PSP, MSA and PD groups in two separate cohorts of parkinsonian patients at both early and advanced stages. Moreover, PSP patients shared many overlapping areas with abnormal metabolism in the same cortical and subcortical regions as in the PSPRP. With rigorous cross-validation, this study demonstrated highly comparable and reproducible PSP-related metabolic topographies at network and regional levels across different patient populations and PET scanners. Metabolic brain network activity may serve as a reliable and objective marker of PSP, although cross-validation applying recent diagnostic criteria and classification is warranted.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/metabolismo , Glucose/metabolismo , Atrofia de Múltiplos Sistemas/metabolismo , Rede Nervosa/metabolismo , Doença de Parkinson/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Paralisia Supranuclear Progressiva/metabolismo , Idoso , Encéfalo/diagnóstico por imagem , China , Diagnóstico Diferencial , Feminino , Fluordesoxiglucose F18/farmacocinética , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Compostos Radiofarmacêuticos/farmacocinética , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Estados Unidos
11.
Proc Natl Acad Sci U S A ; 112(8): 2563-8, 2015 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-25675473

RESUMO

The delineation of resting state networks (RSNs) in the human brain relies on the analysis of temporal fluctuations in functional MRI signal, representing a small fraction of total neuronal activity. Here, we used metabolic PET, which maps nonfluctuating signals related to total activity, to identify and validate reproducible RSN topographies in healthy and disease populations. In healthy subjects, the dominant (first component) metabolic RSN was topographically similar to the default mode network (DMN). In contrast, in Parkinson's disease (PD), this RSN was subordinated to an independent disease-related pattern. Network functionality was assessed by quantifying metabolic RSN expression in cerebral blood flow PET scans acquired at rest and during task performance. Consistent task-related deactivation of the "DMN-like" dominant metabolic RSN was observed in healthy subjects and early PD patients; in contrast, the subordinate RSNs were activated during task performance. Network deactivation was reduced in advanced PD; this abnormality was partially corrected by dopaminergic therapy. Time-course comparisons of DMN loss in longitudinal resting metabolic scans from PD and Alzheimer's disease subjects illustrated that significant reductions appeared later for PD, in parallel with the development of cognitive dysfunction. In contrast, in Alzheimer's disease significant reductions in network expression were already present at diagnosis, progressing over time. Metabolic imaging can directly provide useful information regarding the resting organization of the brain in health and disease.


Assuntos
Doença de Alzheimer/fisiopatologia , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Saúde , Rede Nervosa/fisiopatologia , Doença de Parkinson/fisiopatologia , Descanso , Doença de Alzheimer/metabolismo , Mapeamento Encefálico , Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Atividade Motora , Doença de Parkinson/metabolismo , Tomografia por Emissão de Pósitrons , Análise de Componente Principal , Análise e Desempenho de Tarefas
12.
Hum Brain Mapp ; 38(2): 617-630, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27207613

RESUMO

Spatial covariance mapping can be used to identify and measure the activity of disease-related functional brain networks. While this approach has been widely used in the analysis of cerebral blood flow and metabolic PET scans, it is not clear whether it can be reliably applied to resting state functional MRI (rs-fMRI) data. In this study, we present a novel method based on independent component analysis (ICA) to characterize specific network topographies associated with Parkinson's disease (PD). Using rs-fMRI data from PD and healthy subjects, we used ICA with bootstrap resampling to identify a PD-related pattern that reliably discriminated the two groups. This topography, termed rs-MRI PD-related pattern (fPDRP), was similar to previously characterized disease-related patterns identified using metabolic PET imaging. Following pattern identification, we validated the fPDRP by computing its expression in rs-fMRI testing data on a prospective case basis. Indeed, significant increases in fPDRP expression were found in separate sets of PD and control subjects. In addition to providing a similar degree of group separation as PET, fPDRP values correlated with motor disability and declined toward normal with levodopa administration. Finally, we used this approach in conjunction with neuropsychological performance measures to identify a separate PD cognition-related pattern in the patients. This pattern, termed rs-fMRI PD cognition-related pattern (fPDCP), was topographically similar to its PET-derived counterpart. Subject scores for the fPDCP correlated with executive function in both training and testing data. These findings suggest that ICA can be used in conjunction with bootstrap resampling to identify and validate stable disease-related network topographies in rs-fMRI. Hum Brain Mapp 38:617-630, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Descanso , Adulto , Idoso , Antiparkinsonianos/uso terapêutico , Encéfalo/efeitos dos fármacos , Mapeamento Encefálico , Estudos de Coortes , Feminino , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador , Levodopa/uso terapêutico , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Doença de Parkinson/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Reprodutibilidade dos Testes
13.
Neuroradiology ; 59(5): 507-515, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28386687

RESUMO

PURPOSE: The purpose of this study was to identify the specific metabolic brain pattern characteristic for Parkinson's disease (PD): Parkinson's disease-related pattern (PDRP), using network analysis of [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) brain images in a cohort of Slovenian PD patients. METHODS: Twenty PD patients (age 70.1 ± 7.8 years, Movement Disorder Society Unified Parkinson's Disease Motor Rating Scale (MDS-UPDRS-III) 38.3 ± 12.2; disease duration 4.3 ± 4.1 years) and 20 age-matched normal controls (NCs) underwent FDG-PET brain imaging. An automatic voxel-based scaled subprofile model/principal component analysis (SSM/PCA) was applied to these scans for PDRP-Slovenia identification. RESULTS: The pattern was characterized by relative hypermetabolism in pallidum, putamen, thalamus, brain stem, and cerebellum associated with hypometabolism in sensorimotor cortex, posterior parietal, occipital, and frontal cortices. The expression of PDRP-Slovenia discriminated PD patients from NCs (p < 0.0001) and correlated positively with patients' clinical score (MDS-UPDRS-III, p = 0.03). Additionally, its topography agrees well with the original PDRP (p < 0.001) identified in American cohort of PD patients. We validated the PDRP-Slovenia expression on additional FDG-PET scans of 20 PD patients, 20 NCs, and 25 patients with atypical parkinsonism (AP). We confirmed that the expression of PDRP-Slovenia manifests good diagnostic accuracy with specificity and sensitivity of 85-90% at optimal pattern expression cutoff for discrimination of PD patients and NCs and is not expressed in AP. CONCLUSION: PDRP-Slovenia proves to be a robust and reproducible functional imaging biomarker independent of patient population. It accurately differentiates PD patients from NCs and AP and correlates well with the clinical measure of PD progression.


Assuntos
Encéfalo/metabolismo , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Idoso , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Progressão da Doença , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade
14.
Int J Cancer ; 139(4): 928-37, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27038145

RESUMO

The purpose of our study was to test the hypothesis that sorafenib-related dermatologic adverse events (AEs) as an early biomarker can predict the long-term outcomes following the combination therapy of transarterial chemoembolization (TACE) plus sorafenib (TACE-S). The intermediate-stage hepatocellular carcinoma patients who received either TACE-S or TACE-alone treatment were consecutively included into analysis. In the TACE-S group, patients with ≥ grade 2 dermatologic AEs within the first month of sorafenib initiation were defined as responders; whereas those with < grade 2 were defined as nonresponders. In the TACE-S group, the median overall survival (OS) of the responders was significantly longer than that of nonresponders (28.9 months vs. 16.8 months, respectively; p = 0.004). Multivariate analysis demonstrated that nonresponders were significantly associated with an increased risk of death compared with responders (HR = 1.9; 95% confidence Interval-CI: 1.3-2.7; p = 0.001). The survival analysis showed that the median OS was 27.9 months (95% CI: 25.0-30.8) among responders treated with TACE-S vs.18.3 months (95% CI: 14.5-22.1) among those who received TACE-alone (p = 0.046). The median time to progression was 13.1 months (95% CI: 4.4-21.8) in the TACE-S group, a duration that was significantly longer than that in the TACE-alone group [5 months (95% CI: 6.4-13.3), p = 0.014]. This study demonstrated that sorafenib-related dermatologic AEs are clinical biomarkers to identify responders from all of the patients for TACE-S therapy. Sorafenib-related dermatologic AEs, clinical biomarkers, can predict the efficacy of TACE-S in future randomized controlled trials.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Neoplasias Hepáticas/terapia , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/mortalidade , Quimioembolização Terapêutica/efeitos adversos , Quimioembolização Terapêutica/métodos , Progressão da Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Compostos de Fenilureia/efeitos adversos , Prognóstico , Estudos Retrospectivos , Sorafenibe , Resultado do Tratamento , Adulto Jovem
15.
Anticancer Drugs ; 27(7): 689-94, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27145327

RESUMO

Raltitrexed has shown efficacy and safety in many tumor types; however, the clinical data on the treatment of hepatocellular carcinoma is rare. In this report, we aim to assess the efficacy and safety of raltitrexed plus oxaliplatin (OXA)-based transarterial chemoembolization (TACE) in patients with unresectable hepatocellular carcinoma (uHCC). Patients with uHCC were recruited from multi-centers in China and assigned randomly to raltitrexed+OXA-based (n=76), fluorouracil+OXA-based (n=76), and doxorubicin+OXA-based (n=75) TACE treatment. The primary end point was overall survival (OS). Tumor response was assessed using response evaluation criteria in solid tumors (RECIST), modified response evaluation criteria in solid tumors (mRECIST), and European Association for the Study of the Liver criteria (EASL). Safety and toxicity were evaluated using the National Cancer Institute Common Toxicity Criteria. The raltitrexed group showed a better disease control rate evaluated using RECIST (raltitrexed vs. fluorouracil vs. doxorubicin: 96.1 vs. 84.2 vs. 86.7%, P=0.05) and a better overall response rate on the basis of mRECIST (67.1 vs. 47.4 vs. 50.7%, P=0.03) and EASL (67.1 vs. 47.4 vs. 49.3%, P=0.02). The median OS and median progression-free survival (PFS) were higher in the raltitrexed group (median OS: 13.4 vs. 9.6 vs. 8.5 months; median PFS: 6.7 vs 4.9 vs 4.6 months). The most common toxicities included elevated aspartate aminotransferase (78.9 vs. 86.8 vs. 81.3%) and abdominal nonspecific pain (68.4 vs. 81.6 vs. 78.7%). No significant differences were found in the overall number of patients who experienced any toxicity. Raltitrexed plus OXA-based TACE suggested a safe and efficacious regimen in uHCC patients. The results warrant further clinical investigation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Adulto , Idoso , Doxorrubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Quinazolinas/administração & dosagem , Tiofenos/administração & dosagem , Adulto Jovem
16.
Phytochem Anal ; 27(3-4): 153-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27313152

RESUMO

INTRODUCTION: 5-O-Galloylquinic acid from green tea and other plants is attracting increasing attention for its antioxidant and antileishmanial bioactivities. It is always isolated using a silica column, a Sephadex column and high-performance liquid chromatography (HPLC) methods, which are either laborious or instrument dependent. OBJECTIVE: To develop a new method to easily separate 5-O-galloylquinic acid. METHODOLOGY: Mesoporous zirconium phosphate (m-ZrP) was prepared to conveniently separate 5-O-galloylquinic acid from Chinese green tea extract, and the target compound was easily obtained by simple steps of adsorption, washing and desorption. The effects of the green tea extraction conditions, extract concentrations, and m-ZrP adsorption/desorption dynamics on the 5-O-galloylquinic acid separation were evaluated. RESULTS: 5-O-Galloylquinic acid that was separated from a 70% ethanol extract of green tea was of moderate HPLC purity (92%) and recovery (88%), and an increased non-specific binding of epigallocatechin gallate (EGCG) on m-ZrP was observed in the diluted tea extract. The times for maximal adsorption of 5-O-galloylquinic acid in 70% ethanol extract and maximal desorption of 5-O-galloylquinic acid in 0.4% phosphoric acid solution were confirmed as 7 h and 5 h, respectively. CONCLUSION: A facile method to separate 5-O-galloylquinic acid from Chinese green tea extract using m-ZrP was established. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Antioxidantes/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Ácido Quínico/isolamento & purificação , Chá/química , Zircônio/química , Adsorção , Antioxidantes/química , Catequina/análogos & derivados , Catequina/química , Catequina/isolamento & purificação , Fracionamento Químico , Estrutura Molecular , Extratos Vegetais/química , Ácido Quínico/química
17.
Hum Brain Mapp ; 36(9): 3575-85, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26037537

RESUMO

Parkinson's disease (PD) is associated with distinct metabolic covariance patterns that relate to the motor and cognitive manifestations of the disorder. It is not known, however, how the expression of these patterns relates to measurements of nigrostriatal dopaminergic activity from the same individuals. To explore these associations, we studied 106 PD subjects who underwent cerebral PET with both (18) F-fluorodeoxyglucose (FDG) and (18) F-fluoro-L-dopa (FDOPA). Expression values for the PD motor- and cognition-related metabolic patterns (PDRP and PDCP, respectively) were computed for each subject; these measures were correlated with FDOPA uptake on a voxel-by-voxel basis. To explore the relationship between dopaminergic function and local metabolic activity, caudate and putamen FDOPA PET signal was correlated voxel-wise with FDG uptake over the entire brain. PDRP expression correlated with FDOPA uptake in caudate and putamen (P < 0.001), while PDCP expression correlated with uptake in the anterior striatum (P < 0.001). While statistically significant, the correlations were only of modest size, accounting for less than 20% of the overall variation in these measures. After controlling for PDCP expression, PDRP correlations were significant only in the posterior putamen. Of note, voxel-wise correlations between caudate/putamen FDOPA uptake and whole-brain FDG uptake were significant almost exclusively in PDRP regions. Overall, the data indicate that PDRP and PDCP expression correlates significantly with PET indices of presynaptic dopaminergic functioning obtained in the same individuals. Even so, the modest size of these correlations suggests that in PD patients, individual differences in network activity cannot be explained solely by nigrostriatal dopamine loss.


Assuntos
Encéfalo/metabolismo , Dopamina/metabolismo , Doença de Parkinson/metabolismo , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Radioisótopos de Flúor , Fluordesoxiglucose F18 , Humanos , Levodopa , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/metabolismo , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos
18.
Mov Disord ; 30(9): 1283-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26377152

RESUMO

BACKGROUND: We have previously defined a parkinsonism-related metabolic brain network in rhesus macaques using a high-resolution research positron emission tomography camera. This brief article reports a descriptive pilot study to assess the reproducibility of network activity and regional glucose metabolism in independent parkinsonian macaques using a clinical positron emission tomography/CT camera. METHODS: [(18)F]fluorodeoxyglucose PET scans were acquired longitudinally over 3 months in three drug-naïve parkinsonian and three healthy control cynomolgus macaques. Group difference and test-retest stability in network activity and regional glucose metabolism were evaluated graphically, using all brain images from these macaques. RESULTS: Comparing the parkinsonian macaques with the controls, network activity was elevated and remained stable over 3 months. Normalized glucose metabolism increased in putamen/globus pallidus and sensorimotor regions but decreased in posterior parietal cortices. CONCLUSIONS: Parkinsonism-related network activity can be reliably quantified in different macaques with a clinical positron emission tomography/CT scanner and is reproducible over a period typically employed in preclinical intervention studies. This measure can be a useful biomarker of disease process or drug effects in primate models of Parkinson's disease.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Glucose/metabolismo , Intoxicação por MPTP/diagnóstico por imagem , Intoxicação por MPTP/patologia , Príons/metabolismo , Animais , Mapeamento Encefálico , Modelos Animais de Doenças , Feminino , Fluordesoxiglucose F18/farmacocinética , Macaca fascicularis , Projetos Piloto , Tomografia por Emissão de Pósitrons , Radiografia , Tomógrafos Computadorizados
19.
Brain ; 137(Pt 12): 3122-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25338949

RESUMO

Rapid eye movement sleep behaviour disorder has been evaluated using Parkinson's disease-related metabolic network. It is unknown whether this disorder is itself associated with a unique metabolic network. 18F-fluorodeoxyglucose positron emission tomography was performed in 21 patients (age 65.0±5.6 years) with idiopathic rapid eye movement sleep behaviour disorder and 21 age/gender-matched healthy control subjects (age 62.5±7.5 years) to identify a disease-related pattern and examine its evolution in 21 hemi-parkinsonian patients (age 62.6±5.0 years) and 16 moderate parkinsonian patients (age 56.9±12.2 years). We identified a rapid eye movement sleep behaviour disorder-related metabolic network characterized by increased activity in pons, thalamus, medial frontal and sensorimotor areas, hippocampus, supramarginal and inferior temporal gyri, and posterior cerebellum, with decreased activity in occipital and superior temporal regions. Compared to the healthy control subjects, network expressions were elevated (P<0.0001) in the patients with this disorder and in the parkinsonian cohorts but decreased with disease progression. Parkinson's disease-related network activity was also elevated (P<0.0001) in the patients with rapid eye movement sleep behaviour disorder but lower than in the hemi-parkinsonian cohort. Abnormal metabolic networks may provide markers of idiopathic rapid eye movement sleep behaviour disorder to identify those at higher risk to develop neurodegenerative parkinsonism.


Assuntos
Movimentos Oculares/fisiologia , Redes e Vias Metabólicas/fisiologia , Rede Nervosa/fisiologia , Doença de Parkinson/metabolismo , Transtorno do Comportamento do Sono REM/metabolismo , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Encéfalo/fisiopatologia , Mapeamento Encefálico , Feminino , Humanos , Masculino , Redes e Vias Metabólicas/genética , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Transtorno do Comportamento do Sono REM/etiologia , Transtorno do Comportamento do Sono REM/genética
20.
J Neurosci ; 33(10): 4540-9, 2013 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-23467370

RESUMO

We used a network approach to assess systems-level abnormalities in motor activation in humans with Parkinson's disease (PD). This was done by measuring the expression of the normal movement-related activation pattern (NMRP), a previously validated activation network deployed by healthy subjects during motor performance. In this study, NMRP expression was prospectively quantified in (15)O-water PET scans from a PD patient cohort comprised of a longitudinal early-stage group (n = 12) scanned at baseline and at two or three follow-up visits two years apart, and a moderately advanced group scanned on and off treatment with either subthalamic nucleus deep brain stimulation (n = 14) or intravenous levodopa infusion (n = 14). For each subject and condition, we measured NMRP expression during both movement and rest. Resting expression of the abnormal PD-related metabolic covariance pattern was likewise determined in the same subjects. NMRP expression was abnormally elevated (p < 0.001) in PD patients scanned in the nonmovement rest state. By contrast, network activity measured during movement did not differ from normal (p = 0.34). In the longitudinal cohort, abnormal increases in resting NMRP expression were evident at the earliest clinical stages (p < 0.05), which progressed significantly over time (p = 0.003). Analogous network changes were present at baseline in the treatment cohort (p = 0.001). These abnormalities improved with subthalamic nucleus stimulation (p < 0.005) but not levodopa (p = 0.25). In both cohorts, the changes in NMRP expression that were observed did not correlate with concurrent PD-related metabolic covariance pattern measurements (p > 0.22). Thus, the resting state in PD is characterized by changes in the activity of normal as well as pathological brain networks.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiopatologia , Estimulação Encefálica Profunda/métodos , Atividade Motora/fisiologia , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Idoso , Antiparkinsonianos/uso terapêutico , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Circulação Cerebrovascular , Estudos de Coortes , Óxido de Deutério , Feminino , Humanos , Levodopa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Atividade Motora/efeitos dos fármacos , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/terapia , Tomografia por Emissão de Pósitrons , Núcleo Subtalâmico/fisiologia
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