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1.
Nature ; 610(7933): 656-660, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36289385

RESUMO

Proposed mechanisms for the production of calcium in the first stars (population III stars)-primordial stars that formed out of the matter of the Big Bang-are at odds with observations1. Advanced nuclear burning and supernovae were thought to be the dominant source of the calcium production seen in all stars2. Here we suggest a qualitatively different path to calcium production through breakout from the 'warm' carbon-nitrogen-oxygen (CNO) cycle through a direct experimental measurement of the 19F(p, γ)20Ne breakout reaction down to a very low energy point of 186 kiloelectronvolts, reporting a key resonance at 225 kiloelectronvolts. In the domain of astrophysical interest2, at around 0.1 gigakelvin, this thermonuclear 19F(p, γ)20Ne rate is up to a factor of 7.4 larger than the previous recommended rate3. Our stellar models show a stronger breakout during stellar hydrogen burning than previously thought1,4,5, and may reveal the nature of calcium production in population III stars imprinted on the oldest known ultra-iron-poor star, SMSS0313-67086. Our experimental result was obtained in the China JinPing Underground Laboratory7, which offers an environment with an extremely low cosmic-ray-induced background8. Our rate showcases the effect that faint population III star supernovae can have on the nucleosynthesis observed in the oldest known stars and first galaxies, which are key mission targets of the James Webb Space Telescope9.

2.
Ann Neurol ; 94(4): 672-683, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37377170

RESUMO

OBJECTIVE: Emerging pathological evidence suggests that there is an association between glymphatic dysfunction and the progression of Parkinson's disease (PD). However, the clinical evidence of this association remains lacking. METHODS: In this study, the index for diffusion tensor image analysis along the perivascular space (ALPS index) was calculated to evaluate glymphatic function. RESULTS: Overall, 289 patients with PD were enrolled in the cross-sectional study. The ALPS index was found to be negatively correlated with age, disease severity, and dyskinesia. In the longitudinal study, the information on a total of 95 PD patients with 5-year follow-up examinations was collected from the Parkinson's Progression Marker Initiative, 33 of which were classified into the low ALPS index group, and all others were classified into the mid-high ALPS index group based on the first tertile of the baseline ALPS index. The results of longitudinal regression indicated that there was a significant main group effect on autonomic dysfunction, as well as on activities of daily living. In addition, the low ALPS index group had faster deterioration in MDS-UPDRS part III and part II, Symbol Digit Modalities Test and Hopkins Verbal Learning Test. Path analysis showed that ALPS index acted as a significant mediator between tTau/ Aß1-42 and cognitive change in the Symbol Digit Modalities Test score at year 4 and year 5. INTERPRETATION: The ALPS index, an neuroimaging marker of glymphatic function, is correlated with PD disease severity, motor symptoms, and autonomic function, and is predictive of faster deterioration in motor symptoms and cognitive function. Additionally, glymphatic function may mediate the pathological role of toxic protein in cognitive decline. ANN NEUROL 2023;94:672-683.


Assuntos
Atividades Cotidianas , Doença de Parkinson , Humanos , Estudos Transversais , Estudos Longitudinais , Doença de Parkinson/diagnóstico por imagem , Neuroimagem
3.
Neurol Sci ; 45(1): 155-169, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37578631

RESUMO

OBJECTIVE: Our study aimed to explore the functional connectivity alterations between cortical nodes of resting-state networks in Parkinson's disease (PD) patients with wearing-off (WO) at different levels. METHODS: Resting-state functional magnetic resonance imaging was performed on 36 PD patients without wearing-off (PD-nWO), 30 PD patients with wearing-off (PD-WO), and 35 healthy controls (HCs) to extract functional networks. Integrity, network, and edge levels were calculated for comparison between groups. UPDRS-III, MMSE, MOCA, HAMA, and HAMD scores were collected for further regression analysis. RESULTS: We observed significantly reduced connectivity strength in the dorsal attention network and limbic network in the PD-WO group compared with the HC group. The PD-WO group showed a decreased degree of functional connectivity at 12 nodes, including the bilateral orbital part of the superior frontal gyrus, right olfactory cortex, left medial orbital part of the superior frontal gyrus, bilateral gyrus rectus, right parahippocampal gyrus, right thalamus, left Heschl's gyrus, right superior temporal gyrus part of the temporal pole, left middle temporal gyrus part of the temporal pole, and right inferior temporal gyrus. Furthermore, the PD-WO group showed a significantly lower degree of functional connectivity in the left orbital part of the superior frontal gyrus and right gyrus rectus than the PD-nWO group. Internetwork analysis indicated reduced functional connectivity in five pairs of resting-state networks. CONCLUSION: Our results demonstrated altered intra- and internetwork connections in PD patients with WO. These findings will facilitate a better understanding of the distinction between the network changes in PD pathophysiology.


Assuntos
Mapeamento Encefálico , Doença de Parkinson , Humanos , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/diagnóstico por imagem , Córtex Pré-Frontal , Lobo Temporal
4.
Cell Mol Neurobiol ; 43(8): 4279-4293, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37864627

RESUMO

To investigate the molecular mechanism of communication network factor 1 (CCN1) regulating pentylenetetrazol (PTZ)-induced epileptogenesis, deepen the understanding of epilepsy seizure pathogenesis, and provide new drug action targets for its clinical prevention and treatment. Differentially expressed genes (DEGs) on microarrays GSE47516 and GSE88992 were analyzed online using GEO2R. Pathway enrichment and protein-protein interaction network (PPI) analysis of DEGs were carried out using Metascape. Brain tissue samples of severe traumatic brain injury patients (named Healthy group) and refractory epilepsy patients (named Epilepsy group) were obtained and analyzed by qRT-PCR and immunohistochemistry (IHC) staining. A PTZ-induced epilepsy mouse model was established and verified. Morphological changes of neurons in mouse brain tissue were detected using hematoxylin and eosin (HE) staining. qRT-PCR was conducted to detect the mRNA expressions of apoptosis-associated proteins Bax, Caspase-3 and bcl2. TUNEL staining was performed to detect brain neuron apoptosis. The levels of myocardial enzymology, GSH, MDA and ROS in blood of mouse were detected by biochemical assay. CCN1 expression was increased in epilepsy brain tissue samples. CCN1 decreasing effectively prolongs seizure incubation period and decreases seizure duration. Silencing of CCN1 also reduces neuronal damage and apoptosis, decreases mRNA and protein expression of proapoptotic proteins Bax and Caspase-3, increases mRNA expression of antiapoptotic protein Bcl2. Moreover, decrease of CCN1 decreases myocardial enzymatic indexes CK and CK-MB levels, reduces myocardial tissue hemorrhage, and relieves oxidative stress response in hippocampal and myocardial tissue. CCN1 expression is increased in epileptic samples. CCN1 decreasing protects brain tissue by attenuating oxidative stress and inhibiting neuronal apoptosis triggered by PTZ injection, which probably by regulating Nrf2/HO-1 pathway.


Assuntos
Epilepsia , Pentilenotetrazol , Humanos , Camundongos , Animais , Pentilenotetrazol/efeitos adversos , Caspase 3/metabolismo , Proteína X Associada a bcl-2/metabolismo , Epilepsia/induzido quimicamente , Epilepsia/genética , Epilepsia/tratamento farmacológico , Convulsões/induzido quimicamente , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo
5.
J Neural Transm (Vienna) ; 130(4): 549-560, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36859555

RESUMO

Cerebellar dysfunction may substantially contribute to the clinical symptoms of Parkinson's disease (PD). The role of cerebellar subregions in tremors and gait disturbances in PD remains unknown. To investigate alterations in cerebellar subregion volumes and functional connectivity (FC), as well as FC between the dentate nucleus (DN) and ventral lateral posterior nucleus (VLp) of the thalamus, which are potentially involved in different PD motor subtypes. We conducted morphometric and resting-state functional connectivity analyses in various cerebellar subregions in 22 tremor-dominant (TD)-PD and 35 postural instability gait difficulty dominant (PIGD)-PD patients and 38 sex- and age-matched healthy controls (HCs). The volume and FC alterations in various cerebellar subregions and the neural correlates of these changes with the clinical severity scores were investigated. The PIGD-PD group showed greater FC between the right motor cerebellum (CBMm) and left postcentral gyrus than the HC group, and a higher FC was associated with less severe PIGD symptoms. In contrast, the TD-PD group had decreased FC between the right DN and left VLp compared with the PIGD-PD and HC groups, and lower FC was associated with worse TD symptoms. Furthermore, the PIGD-PD group had higher FC between the left DN and left inferior temporal gyrus than the TD-PD group. Morphometric analysis revealed that the TD-PD group showed a significantly higher volume of left CBMm than the HC group. Our findings point to differential alteration patterns in cerebellar subregions and offer a new perspective on the pathophysiology of motor subtypes of PD.


Assuntos
Transtornos Neurológicos da Marcha , Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tremor/etiologia , Tremor/complicações , Cerebelo/diagnóstico por imagem , Córtex Somatossensorial , Transtornos Neurológicos da Marcha/diagnóstico por imagem , Transtornos Neurológicos da Marcha/etiologia
6.
BMC Neurol ; 23(1): 350, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794323

RESUMO

BACKGROUND: Chorea-acanthocytosis (ChAc) is a rare hereditary autosomal recessive neurodegenerative disorder caused by pathogenic variants of the Vacuolar Protein Sorting 13 homolog A (VPS13A) gene. The variant spectrum of VPS13A has not been completely elucidated. This study reports two novel heterozygous VPS13A pathogenic variants in ChAc that expand the variant spectrum of VPS13A. CASE PRESENTATION: We described a case of a 29-year-old man with typical clinical manifestations of ChAc, including chorea, orofacial lingual dyskinesia, vocal tics, elevated serum biochemical indicators, increased acanthocytes in peripheral blood, and caudate nucleus atrophy. Next-generation sequencing revealed two heterozygous variants of VPS13A: a nonsense variant (NM_033305.2: c.8215G > T, p. Glu2739Ter) and a deletion variant in the exons 25-31. CONCLUSION: The identified nonsense variant gives rise to premature translation termination, while the deletion variant is expected to cause a significant in-frame deletion of amino acid residues in the encoded protein. Both variants are considered to be pathogenic and result in loss-of-function proteins. These findings have implications for the genetic counseling of patients with VPS13A variants.


Assuntos
Discinesias , Neuroacantocitose , Tiques , Masculino , Humanos , Adulto , Neuroacantocitose/genética , Proteínas de Transporte Vesicular/genética , Núcleo Caudado/metabolismo , Núcleo Caudado/patologia
7.
J Environ Manage ; 317: 115296, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35644676

RESUMO

Energy-saving reconstruction of old residential buildings is a vital way to achieve sustainable development, but the potential of rooftop photovoltaic (PV) energy-saving in old residential buildings has not been studied. This study established a basic framework for the estimation of rooftop PV technical, economic and environmental potential in the old residential buildings of Nanjing City, and provide the prediction results for the development of rooftop PV development plan in Nanjing. We estimated the available area, maximum electricity generation, environmental and economic benefits of rooftop PV in five districts of Nanjing by using building roof profile data, calculation method of maximum solar radiation at optimal tilt angle and GIS method. We find that the electricity generation potential of installing rooftop PV in the old residential buildings in the study area would meet about 17.7-20% of the residential electricity demand under three scenarios of the PV performance ratios (PR). Additionally, the carbon reduction potential of the life cycle rooftop PV reaches 13912874.12t (PR = 0.85), 13094469.76t (PR = 0.8), and 12276065.4t (PR = 0.75), respectively; and the result of economic potential shows that the life cycle of rooftop PV cannot generate economic benefits with an NPV value less than 0. The feasibility analysis framework provided in this paper can be applied to the assessment of rooftop PV potential in other cities in China, and provide valuable advice for the rational planning of rooftop PV.


Assuntos
Energia Solar , Carbono , China , Cidades , Eletricidade
8.
Eur Radiol ; 31(10): 7386-7394, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33389038

RESUMO

OBJECTIVES: To analyse the changes of quantitative electroencephalogram (qEEG) and cortex structural magnetic resonance (MR) imaging in Parkinson's disease with mild cognitive impairment (PD-MCI) and to explore the "composite marker"-based machine learning model in identifying PD-MCI. METHODS: Retrospective analysis of patients with PD identified 36 PD-MCI and 35 PD with normal cognition (PD-NC). QEEG features of power spectrum and structural MR features of cortex based on surface-based morphometry (SBM) were extracted. Support vector machine (SVM) was established using combined features of structural MR and qEEG to identify PD-MCI. Feature importance evaluation algorithm of mean impact value (MIV) was established to sort the vital characteristics of qEEG and structural MR. RESULTS: Compared with PD-NC, PD-MCI showed a statistically significant difference in 5 leads and waves of qEEG and 7 cortical region features of structural MR. The SVM model based on these qEEG and structural MR features yielded an accuracy of 0.80 in the training set and had a high prediction accuracy of 0.80 in the test set (sensitivity was 0.78, specificity was 0.83, area under the receiver operating characteristic curve was 0.77), which was higher than the model built by the feature separately. QEEG features of theta wave in C3 had a marked impact on the model for classification according to the MIV algorithm. CONCLUSIONS: PD-MCI is characterized by widespread structural and EEG abnormality. "Composite markers" could be valuable for the individualized diagnosis of PD-MCI by machine learning. KEY POINTS: • Explore the brain abnormalities in Parkinson's disease with mild cognitive impairment by using the quantitative electroencephalogram and cortex structural MR simultaneously. • Multimodal features based support vector machine for identifying Parkinson's disease with mild cognitive impairment has an acceptable performance. • Theta wave in C3 is the most influential feature of qEEG and cortex structure MR imaging in identifying Parkinson's disease with mild cognitive impairment using support vector machine.


Assuntos
Disfunção Cognitiva , Doença de Parkinson , Disfunção Cognitiva/diagnóstico por imagem , Eletroencefalografia , Humanos , Imageamento por Ressonância Magnética , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Estudos Retrospectivos
9.
Int J Neurosci ; 131(4): 411-424, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32253965

RESUMO

Background: Nowadays, antidepressants still are the mainstay of treatment for depression in Parkinson's disease (PD) but some recent studies report that medication might aggravate motor symptoms in PD patients. This meta-analysis aims to assess the effect of non-pharmacological treatments for depression in patients with PD.Materials and Methods: Only randomized controlled trials (RCTs) were included. The participants were PD patients with comorbid depression (dPD). The interventions had the equivalent effect of non-pharmacological treatments alone compared with control(s). Scores of depression scale were selected as the primary outcome, while scores of Unified Parkinson's Disease Rating Scale part III and the incidence of side effects were the secondary outcome. The statistics were pooled and presented as weighted mean differences (WMDs), standardized mean differences (SMDs), or risk ratios (RRs) with their 95% confidence intervals (CIs).Results: Fifteen articles were eventually included; twelve studies reported on repetitive transcranial magnetic stimulation (rTMS) and three used cognitive behavioral therapy (CBT). Other interventions failed to have qualified studies. Our data indicated that both rTMS and CBT could significantly improve depression scores in a short term (SMD = -0.621, 95% CI [-0.964, -0.278]; SMD = -1.148, 95% CI [-1.498, -0.798], respectively). In addition, rTMS could alleviate motor symptom (WMD = -2.617, 95% CI [-4.183, -1.051]) and was relatively safe (RR = 1.054, 95% CI [0.698, 1.592]).Conclusion: Our data suggest that rTMS can safely alleviate depression and motor symptoms in dPD at least for a short period. Moreover, compared with clinical monitoring, CBT can improve depressive symptoms.


Assuntos
Terapia Cognitivo-Comportamental , Depressão/complicações , Doença de Parkinson/complicações , Doença de Parkinson/terapia , Estimulação Magnética Transcraniana , Terapia Combinada , Humanos , Resultado do Tratamento
10.
Neuroradiology ; 62(2): 167-174, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31673747

RESUMO

PURPOSE: Computed tomography (CT) perfusion (CTP) source images contain both brain perfusion and cerebrovascular information, and may allow a dynamic assessment of collaterals. The purpose of the study was to compare the image quality and the collaterals identified on multiphase CT angiography (CTA) derived from CTP datasets (hereafter called CTPA) reconstructed with iterative model reconstruction (IMR) algorithm in patients with middle cerebral artery (MCA) steno-occlusion with those of routine CTA. METHODS: Consecutive patients with a unilateral MCA steno-occlusion underwent non-contrast CT (NCCT), CTP, and CTA. CTPA images were reconstructed from CTP datasets. The vascular attenuation, image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of routine CTA and CTPA were measured and analyzed by Student's t test. Subjective image quality and collaterals were scored and compared using the Wilcoxon signed-rank test. RESULTS: Fifty-eight patients (mean age 61.7 years, 78% males, median National Institutes of Health Stroke Scale score = 12) were included. The effective radiation dose of CTP was 1.28 mSv. The vascular attenuation, SNR, CNR, and the image quality of CTPA were considerably higher than that of CTA (all, p < 0.001). Collaterals were rated higher on CTPA compared with CTA (1.79 ± 0.64 vs. 1.22 ± 0.84, p < 0.001). Fifty-three percent of patients with poor collaterals assessed on single-phase CTA had good collaterals on CTPA. CONCLUSION: CTPA derived from CTP datasets reconstructed with IMR algorithm offers image quality comparable to routine CTA and provides time-resolved evaluation of collaterals in patients with MCA ischemic disease.


Assuntos
Arteriopatias Oclusivas/diagnóstico por imagem , Angiografia Cerebral/métodos , Doenças Arteriais Cerebrais/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Artéria Cerebral Média/diagnóstico por imagem , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Razão Sinal-Ruído
11.
Neuroradiology ; 62(10): 1323-1334, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32494963

RESUMO

PURPOSE: To evaluate the feasibility and safety of endovascular recanalization for symptomatic subacute and chronic internal carotid artery occlusion (ICAO); to propose a newly modified radiographic classification of ICAO that can rigorously identify suitable candidates for endovascular ICAO treatment. METHODS: We included 42 consecutive patients who had ICAO with ischaemic symptoms refractory to medical therapy. We examined the symptomatology, complications, follow-up results and radiographic images of ICAO receiving attempted endovascular treatment. We attempted to stratify all radiographic images into categories based on morphological occlusion patterns, occlusion segments and distal ICA reconstitution on digital subtraction angiography (DSA). RESULTS: Four types (A-D) of radiographic ICAO were identified. We redefined type B as having a tapered stump but no distal lumen. The rate of successful recanalization was 83.33% (35/42 ICAOs; type A, 18/20; type B, 7/10; type C, 10/11; type D, 0/1). The perioperative complication rate was 11.90% (5/42), including 3 asymptomatic distal embolisms, 1 symptomatic cerebral infarction and 1 asymptomatic carotid artery dissection. None of these technique-related complications led to severe neurological damage or death. Modified Rankin Scale (mRS) scores after 1-20 months of follow-up were significantly decreased in successfully revascularized patients (P < 0.001). There was no significant change in mRS scores in the 7 patients in whom recanalization failed (P > 0.05). CONCLUSIONS: Endovascular recanalization seems to achieve technical success and clinical improvement for symptomatic subacute and chronic ICAO. Additionally, our newly modified radiographic classification of ICAO may be valuable in assessing the technical feasibility and safety of procedures in symptomatic ICAO patients.


Assuntos
Artéria Carótida Interna , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Procedimentos Endovasculares/métodos , Neuroimagem/métodos , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Estudos Retrospectivos
12.
Neurol Sci ; 41(4): 809-815, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31792718

RESUMO

BACKGROUND: Idiopathic rapid eye movement sleep behavior disorder (iRBD) is an important risk factor for α-synucleinopathy. OBJECTIVE: We investigated alterations in the cerebral blood flow (CBF) based on arterial spin-labeled (ASL) imaging in patients with iRBD to determine brain perfusion changes associated with the disorder. METHODS: Fifteen patients with iRBD and twenty age-gender-matched healthy controls were enrolled. Cortical perfusions were compared between the two groups after the ASL data was co-registered to the high-resolution T1-weighted images. RESULTS: No significant differences were detected between the groups in regard to age, gender, education, or UPDRS-III score. The iRBD group showed a lower MMSE score than the healthy controls (27.07 ± 2.25 vs. 28.55 ± 1.23, p < 0.05). Compared with the healthy controls, the iRBD group showed significantly decreased CBF values in the right inferior frontal gyrus, right middle frontal gyrus, and right insula (p < 0.05 corrected). CONCLUSION: The cortical hypoperfusion areas in patients with iRBD were similar to the patterns in patients with α -synucleinopathies. ASL perfusion MRI is a potential approach to find biomarkers in preclinical stages of α -synucleinopathies.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Circulação Cerebrovascular , Angiografia por Ressonância Magnética , Transtorno do Comportamento do Sono REM/diagnóstico por imagem , Sinucleinopatias/diagnóstico por imagem , Idoso , Córtex Cerebral/fisiopatologia , Circulação Cerebrovascular/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Transtorno do Comportamento do Sono REM/fisiopatologia , Marcadores de Spin , Sinucleinopatias/fisiopatologia
13.
Sensors (Basel) ; 20(17)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32846961

RESUMO

Ocean latent heat flux (LHF) is an essential variable for air-sea interactions, which establishes the link between energy balance, water and carbon cycle. The low-latitude ocean is the main heat source of the global ocean and has a great influence on global climate change and energy transmission. Thus, an accuracy estimation of high-resolution ocean LHF over low-latitude area is vital to the understanding of energy and water cycle, and it remains a challenge. To reduce the uncertainties of individual LHF products over low-latitude areas, four machine learning (ML) methods (Artificial Neutral Network (ANN), Random forest (RF), Bayesian Ridge regression and Random Sample Consensus (RANSAC) regression) were applied to estimate low-latitude monthly ocean LHF by using two satellite products (JOFURO-3 and GSSTF-3) and two reanalysis products (MERRA-2 and ERA-I). We validated the estimated ocean LHF using 115 widely distributed buoy sites from three buoy site arrays (TAO, PIRATA and RAMA). The validation results demonstrate that the performance of LHF estimations derived from the ML methods (including ANN, RF, BR and RANSAC) were significantly better than individual LHF products, indicated by R2 increasing by 3.7-46.4%. Among them, the LHF estimation using the ANN method increased the R2 of the four-individual ocean LHF products (ranging from 0.56 to 0.79) to 0.88 and decreased the RMSE (ranging from 19.1 to 37.5) to 11 W m-2. Compared to three other ML methods (RF, BR and RANSAC), ANN method exhibited the best performance according to the validation results. The results of relative uncertainty analysis using the triangle cornered hat (TCH) method show that the ensemble LHF product using ML methods has lower relative uncertainty than individual LHF product in most area. The ANN was employed to implement the mapping of annual average ocean LHF over low-latitude at a spatial resolution of 0.25° during 2003-2007. The ocean LHF fusion products estimated from ANN methods were 10-30 W m-2 lower than those of the four original ocean products (MERRA-2, JOFURO-3, ERA-I and GSSTF-3) and were more similar to observations.

14.
Ann Vasc Surg ; 58: 338-346, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30769077

RESUMO

BACKGROUND: The aims of this study were to explore (i) the dynamic changes in cerebral microbleeds (CMBs) in patients with symptomatic cerebral artery stenosis who received endovascular stent-assisted angioplasty and (ii) the risk factors associated with the new incidence of CMBs as well as whether CMBs increased the risk of vascular events in these patients. METHODS: Clinical information and magnetic resonance images were collected on admission and 3 months after endovascular stent-assisted angioplasty. Based on susceptibility-weighted imaging, the patients were divided into groups with or without newly developed CMBs, and between-group differences in risk factors were compared. We also compared whether CMBs increased the risk of vascular events among those patients. RESULTS: Seventy-three patients completed the relevant follow-up examinations. After an average follow-up period of 109 days, 7 (9.6%) patients showed new CMBs. A univariate analysis showed that the number of lacunar infarcts and the increase in systolic blood pressure were higher in patients with new CMBs than in those without new CMBs, and these differences were significant (P = 0.034, P = 0.001). Increased systolic blood pressure was an independent risk factor for developing new CMBs (P = 0.017). CONCLUSIONS: CMBs may be a continuously progressing cerebral small-vessel disease. The newly developed CMBs in patients with intracranial and/or extracranial stents were associated with increased systolic blood pressure but not with the number of baseline CMBs.


Assuntos
Angioplastia/instrumentação , Doenças Arteriais Cerebrais/terapia , Hemorragia Cerebral/etiologia , Doenças de Pequenos Vasos Cerebrais/terapia , Stents , Idoso , Angiografia Digital , Angioplastia/efeitos adversos , Pressão Sanguínea , Angiografia Cerebral/métodos , Doenças Arteriais Cerebrais/complicações , Doenças Arteriais Cerebrais/diagnóstico por imagem , Doenças Arteriais Cerebrais/fisiopatologia , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/fisiopatologia , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/fisiopatologia , Imagem de Difusão por Ressonância Magnética , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Sístole , Fatores de Tempo , Resultado do Tratamento
15.
Biochem Biophys Res Commun ; 499(4): 797-802, 2018 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-29621548

RESUMO

Neuroinflammation and overactivated microglia underlies the pathogenesis of Parkinson's disease (PD). Furthermore, microglia could polarize into classic inflammatory M1 and immunosuppressive M2 phenotype. Thus, inhibiting the overactivated inflammatory M1 microglia by promoting the transformation of microglia to the protective M2 phenotype provides potential therapy for PD, but the mechanism that modulates microglia polarization remains unknown. Triggering receptor expressed on myeloid cells-2 (TREM2) is a recently identified immune receptor expressed by the microglia in the brain. Emerging evidence indicates that TREM2 enhances the phagocytosis function of microglia and suppress inflammation. Based on these evidence, we hypothesized that TREM2 might play a protective role through regulating microglia polarization. Here, we employ a lentiviral strategy to overexpress or suppress TREM2 on microglia and found that TREM2 was essential for M2 microglia polarization. Knockdown of TREM2 in BV2 microglia inhibited M2 polarization and lead to exaggeration of M1 microglial inflammatory responses, whereas overexpression of TREM2 promoted M2 polarization and alleviated microglial inflammation. We also observed that the TREM2 level was higher in the midbrain of PD mice, which was accompanied by an elevated level of Arginase-1 and increased proinflammatory cytokines, suggesting that TREM2 is an important factor in switching the microglia phenotypes. Taken together, these findings indicate that TREM2 plays a crucial role in altering the proinflammatory M1 microglia to M2 phenotype and has beneficial effects in the immune pathogenesis of PD.


Assuntos
Inflamação/metabolismo , Inflamação/patologia , Glicoproteínas de Membrana/metabolismo , Microglia/metabolismo , Microglia/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Receptores Imunológicos/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Animais , Arginase/metabolismo , Linhagem Celular , Polaridade Celular , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Técnicas de Silenciamento de Genes , Lentivirus/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Doença de Parkinson/genética , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução Genética , Regulação para Cima/genética
16.
BMC Neurol ; 18(1): 221, 2018 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-30591018

RESUMO

BACKGROUND: Dopamine agonists (DAs) are efficacious for the treatment of motor and nonmotor symptoms in patients with Parkinson's disease (PD). The treatment of PD with DAs is often complicated by adverse drug reactions (ADRs) of dopaminergic and non-dopaminergic origins. The DA piribedil is widely used in Asian, European, and Latin American countries; therefore, its ADRs are pertinent to clinicians. Here we present a rare case of hypotension and bradycardia that is significantly related to the dosage of piribedil. CASE PRESENTATION: A middle-aged male, diagnosed with PD, received dopamine replacement with piribedil. When taking 50 mg piribedil daily dose, the patient didn't feel any discomfort. Two hours after taking 100 mg piribedil he presented with serious concomitant hypotension and bradycardia with a blood pressure (BP) reading of 85/48 mmHg and a heart rate (HR) of 45 beats/min when sitting. After taking 75 mg piribedil, the patient showed the same symptoms with BP reading at 70/45 mmHg and HR of 47 beats/min in the same position. Upon replacing treatment with pramipexole 0.125 mg, 0.25 mg, and 0.375 mg three times a day, no further cardiovascular effects persisted. CONCLUSIONS: No studies have previously reported the simultaneous observation of position-unrelated hypotension and bradycardia after taking small doses of piribedil. More studies are needed to explore the effects of DAs on BP and HR, especially piribedil. Piribedil is efficacious for the treatment of PD, but it is important to weigh the potential risk of hypotension and bradycardia against the clinical benefits of this drug.


Assuntos
Bradicardia/induzido quimicamente , Hipotensão/induzido quimicamente , Piribedil/efeitos adversos , Dopamina/metabolismo , Agonistas de Dopamina/administração & dosagem , Agonistas de Dopamina/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/tratamento farmacológico , Piribedil/administração & dosagem , Pramipexol/administração & dosagem
18.
Int J Neurosci ; 127(1): 66-72, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26785609

RESUMO

The aim of this study was to investigate changes in brain activity associated with mild cognitive impairment (MCI) in a large sample of nondemented Parkinson's disease (PD) patients and its relationship with specific neuropsychological deficits. Electroencephalography (EEG) and neuropsychological assessment were performed in a sample of 135 nondemented PD patients and 44 healthy controls. All patients underwent a neuropsychological battery to assess global cognitive function. Patients were classified according to their cognitive status as PD patients with MCI (n = 61) and without MCI (n = 74). EEG data were used to analyze the relative band power parameters for the following frequency bands: delta (0.5-4 Hz), theta (4-8 Hz), alpha (8-13 Hz) and beta (13-30 Hz). In addition, relative band power parameters were compared between groups and examined for correlations with neuropsychological performance. The relative theta band powers in three regions (O1, T5 and F4) exhibited statistically significant increases in PD patients with MCI. Beta band powers also exhibited obvious decreases in five regions (T5, T6, P3, P4 and C3) in the PD-MCI group compared with the normal control group. Furthermore, correlation analyses revealed that attention, visuospatial and executive functions were associated with theta power in local regions, mainly in the frontal region (F4). The present study demonstrated that changes in brain activities limited to distinct cognitive domains, especially the theta power in the frontal region, could serve as an electrophysiological marker of cognitive impairment in nondemented PD patients.


Assuntos
Disfunção Cognitiva/fisiopatologia , Lobo Frontal/fisiopatologia , Lobo Occipital/fisiopatologia , Doença de Parkinson/fisiopatologia , Lobo Temporal/fisiopatologia , Ritmo Teta/fisiologia , Adulto , Idoso , Disfunção Cognitiva/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações
19.
Int J Neurosci ; 127(11): 1028-1035, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28281852

RESUMO

The aim of this study was to investigate the patterns of brain activity changes in early-onset Parkinson's disease (EOPD) patients and its relationship with the severity of disease and motor deterioration. Electroencephalography (EEG) was performed in a sample of 52 nondemented EOPD patients and 20 healthy controls with similar age. All patients underwent a battery to assess PD severity and motor deterioration. The EEG data were rated by visual and quantitative analyses with the grant total EEG (GTE) score and NicoletOne Software. The parameters of relative band power and coherences for various frequency bands were calculated. In addition, all parameters were compared between groups and examined for correlations with the severity of disease and motor deterioration. The GTE score and two subscores including "Diffuse Slow Waves" and "Frequency of Rhythmic Background Activity" of EOPD increased comparing to control group. The relative beta band powers in seven regions (O1,O2,T5,T6,P3,P4 and C3) indicated significant decreases in EOPD patients and obvious increases in interhemispheric beta coherences were observed in the midtemporal area and frontal area (T3T4 and F3F4). Furthermore, correlation analyses revealed that longer duration was associated with the subscore of "background wave frequency". The beta frequency bands in the right posterior temporal (T6) showed negative relationship with the modified Hoehn-Yahr grading scores. This study is the first to depict the patterns of EEG changes in EOPD patients without dementia and offer a better understanding of the pathophysiological mechanisms underlying and prognostic purposes in EOPD. Some of these changes could serve as useful biomarkers in the study of EOPD.


Assuntos
Ondas Encefálicas/fisiologia , Córtex Cerebral/fisiopatologia , Sincronização de Fases em Eletroencefalografia/fisiologia , Doença de Parkinson/fisiopatologia , Adulto , Idade de Início , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
20.
Int J Neurosci ; 126(3): 227-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26001202

RESUMO

AIM: To investigate the influence of onset age on the occurrence and progression of cognitive dysfunction using neuropsychological tests and the electrophysiological component P300 in both early-onset Parkinson's disease (EOPD) and late-onset Parkinson's disease (LOPD) patients. METHODS: A cohort of 76 EOPD patients and 166 LOPD patients was recruited for this study. Demographic information and clinical features, including age, disease duration, education level, family history, the Unified Parkinson's Disease Rating Scale, the Hoehn and Yahr stage, and depression scores were documented for each patient. The Mini-Mental State Examination, Montreal Cognitive Assessment (MoCA), Wechsler Adult Intelligence Scale - Revised, Chinese version (WAIS-RC) and Wechsler Memory Scale - Revised, Chinese version (WMS-RC) were used. In addition, P300 was also examined to assess cognitive function. RESULTS: Although EOPD patients had longer disease duration, their cognitive dysfunction progressed more slowly. The MoCA tests revealed that EOPD patients had higher scores in visuospatial function, attention, delayed recall, and orientation than the LOPD patients. The difference between the two groups on the WMS-RC test did not reach significance, whereas the scores in executive function, visuospatial function and attention as measured on the WAIS-RC test were significantly lower in the LOPD group. In addition, P300 latencies were markedly delayed and P300 amplitudes were reduced in the LOPD group. CONCLUSIONS: The current findings demonstrated that cognitive dysfunction progressed more slowly in the EOPD group. Although the LOPD patients exhibited shorter disease durations, their cognitive abilities, including executive function, visuospatial function and attention, may have been impaired.


Assuntos
Idade de Início , Atenção/fisiologia , Cognição/fisiologia , Função Executiva/fisiologia , Doença de Parkinson/psicologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Doença de Parkinson/diagnóstico
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