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1.
Artigo em Inglês | MEDLINE | ID: mdl-38598680

RESUMO

Flexible foam-based sensors have attracted substantial interest due to their high specific surface area, light weight, superior deformability, and ease of manufacture. However, it is still a challenge to integrate multimodal stimuli-responsiveness, high sensitivity, reliable stability, and good biocompatibility into a single foam sensor. To achieve this, a magnetoresistive foam sensor was fabricated by an in situ freezing-polymerization strategy based on the interpenetrating networks of sodium alginate, poly(vinyl alcohol) in conjunction with glycerol, and physical reinforcement of core-shell bidisperse magnetic particles. The assembled sensor exhibited preferable magnetic/strain-sensing capability (GF ≈ 0.41 T-1 for magnetic field, 4.305 for tension, -0.735 for bending, and -1.345 for pressing), quick response time, and reliable durability up to 6000 cycles under external stimuli. Importantly, a machine learning algorithm was developed to identify the encryption information, enabling high recognition accuracies of 99.22% and 99.34%. Moreover, they could be employed as health systems to detect human physiological motion and integrated as smart sensor arrays to perceive external pressure/magnetic field distributions. This work provides a simple and ecofriendly strategy to fabricate biocompatible foam-based multimodal sensors with potential applications in next-generation soft electronics.

2.
World J Urol ; 42(1): 36, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38217714

RESUMO

PURPOSE: This prospective study aimed to explore the microstructural alterations of the white matter in overactive bladder syndrome (OAB) using the Tract-based Spatial Statistics (TBSS) method of diffusion kurtosis imaging (DKI). METHODS: A total of 30 patients were enrolled and compared with 30 controls. White matter (WM) status was assessed using tract-based spatial statistics for DKI. The differences in DKI-derived parameters, including kurtosis fractional anisotropy (KFA), fractional anisotropy (FA), mean kurtosis (MK), mean diffusivity (MD), radial kurtosis (RK), axial kurtosis (AK), axial diffusivity (AD), and radial diffusivity (RD), were compared between the two groups using the TBSS method. The correlation between the altered DKI-derived parameters and the (OABSS) scores was analyzed. A receiver operating characteristic curve (ROC) was used to evaluate the diagnostic performance of different white matter parameters. RESULTS: As a result, compared with the HC group, the KFA, and FA values decreased significantly in the OAB group. Compared with the HC group, the MK and MD values increased significantly in the OAB group. The KFA values of the genu of corpus callosum (GCC) were significantly correlated with the OABSS scores (r = - 0.509; p = 0.004). The FA values of anterior corona radiata (ACR) were significantly correlated with OABSS scores (r = - 0.447; p = 0.013). The area under the ROC curve (AUC) for the genu of corpus callosum KFA values was higher than FA for the diagnosis of OAB patients. CONCLUSION: DKI is a promising approach to the investigation of the pathophysiology of OAB and a potential biomarker for clinical diagnosis of OAB.


Assuntos
Bexiga Urinária Hiperativa , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Estudos Prospectivos , Bexiga Urinária Hiperativa/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Encéfalo
3.
Front Oncol ; 13: 1244585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38304033

RESUMO

Objectives: To develop a CT-based radiomics model and a combined model for preoperatively discriminating infiltrative renal cell carcinoma (RCC) and pyelocaliceal upper urinary tract urothelial carcinoma (UTUC), which invades the renal parenchyma. Materials and methods: Eighty patients (37 pathologically proven infiltrative RCCs and 43 pathologically proven pyelocaliceal UTUCs) were retrospectively enrolled and randomly divided into a training set (n = 56) and a testing set (n = 24) at a ratio of 7:3. Traditional CT imaging characteristics in the portal venous phase were collected by two radiologists (SPH and ZXL, who have 4 and 30 years of experience in abdominal radiology, respectively). Patient demographics and traditional CT imaging characteristics were used to construct the clinical model. The radiomics score was calculated based on the radiomics features extracted from the portal venous CT images and the random forest (RF) algorithm to construct the radiomics model. The combined model was constructed using the radiomics score and significant clinical factors according to the multivariate logistic regression. The diagnostic efficacy of the models was evaluated using receiver operating characteristic (ROC) curve analysis and the area under the curve (AUC). Results: The RF score based on the eight validated features extracted from the portal venous CT images was used to build the radiomics model. Painless hematuria as an independent risk factor was used to build the clinical model. The combined model was constructed using the RF score and the selected clinical factor. Both the radiomics model and combined model showed higher efficacy in differentiating infiltrative RCC and pyelocaliceal UTUC in the training and testing cohorts with AUC values of 0.95 and 0.90, respectively, for the radiomics model and 0.99 and 0.90, respectively, for the combined model. The decision curves of the combined model as well as the radiomics model indicated an overall net benefit over the clinical model. Both the radiomics model and the combined model achieved a notable reduction in false-positive and false-negativerates, resulting in significantly higher accuracy compared to the visual assessments in both the training and testing cohorts. Conclusion: The radiomics model and combined model had the potential to accurately differentiate infiltrative RCC and pyelocaliceal UTUC, which invades the renal parenchyma, and provide a new potentially non-invasive method to guide surgery strategies.

4.
Nanomaterials (Basel) ; 12(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36014627

RESUMO

Recently, flexible sensors have gained significant attention due to their potential applications in soft robotics and biomimetic intelligent devices. However, the successful production of favorable flexible sensors integrated with high flexibility, sensitivity and excellent environment adaptability toward multiple external stimuli is still an enormous challenge. Herein, a lightweight polymeric porous sponge capable of detecting an external magnetic field and strain excitations is proposed by assembling a sodium alginate/chitosan (SA/CHI) porous sponge with micron carbonyl iron and nanoscale Fe3O4 magnetic particles (MPs). Based on the double network structure, the SA/CHI sponge possesses preferable mechanical strength and hydrophilicity, demonstrating its high flexibility and deformability. More importantly, the electrical response of the SA/CHI sponge sensors can display remarkable variation under external magnetic and mechanical stimuli due to their superior magnetic characteristics and electrical conductivity. Meanwhile, their sensing properties can maintain relatively stable recoverability and repeatability towards the periodic excitations and releases. Additionally, a potential mechanism is provided to investigate their stimuli-sensitive behavior. It is highly dependent on the microstructure variations in MPs and conductive multi-walled carbon nanotube (MWCNTs) networks. Due to its exceptional magnetic controllability and appropriate electrical sensitivity, the proposed sensor shows high potential in wearable multi-sensing electronics and intelligent transport devices.

5.
Eur Arch Psychiatry Clin Neurosci ; 272(6): 1033-1043, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34626218

RESUMO

Hubs in the brain network are the regions with high centrality and are crucial in the network communication and information integration. Patients with schizophrenia (SCZ) exhibit wide range of abnormality in the hub regions and their connected functional connectivity (FC) at the whole-brain network level. Study of the hubs in the brain networks supporting complex social behavior (social brain network, SBN) would contribute to understand the social dysfunction in patients with SCZ. Forty-nine patients with SCZ and 27 healthy controls (HC) were recruited to undertake the resting-state magnetic resonance imaging scanning and completed a social network (SN) questionnaire. The resting-state SBN was constructed based on the automatic analysis results from the NeuroSynth. Our results showed that the left temporal lobe was the only hub of SBN, and its connected FCs strength was higher than the remaining FCs in both two groups. SCZ patients showed the lower association between the hub-connected FCs (compared to the FCs not connected to the hub regions) with the real-life SN characteristics. These results were replicated in another independent sample (30 SCZ and 28 HC). These preliminary findings suggested that the hub-connected FCs of SBN in SCZ patients exhibit the abnormality in predicting real-life SN characteristics.


Assuntos
Mapeamento Encefálico , Esquizofrenia , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Vias Neurais/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Rede Social
6.
Int Urol Nephrol ; 53(1): 27-33, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32851576

RESUMO

OBJECTIVES: To investigate whether patients with overactive bladder syndrome (OAB) have brain volume changes using voxel-based morphometry (VBM) and correlations with clinical tests. METHODS: With institutional review board approval and after obtaining written informed consent, structural magnetic resonance imaging data were prospectively acquired in 28 patients and 28 control subjects. OAB symptoms were assessed using the OAB symptom score (OABSS) scale. The gray matter volume (GMV) of each voxel was compared between the two groups while controlling for the effects of age, sex, and education level. Correlation analysis was performed to identify correlations between abnormal GMV regions and OABSS scores in patients. Multiple comparisons were corrected using a false discovery rate (FDR) method. RESULTS: Patients with OAB exhibited a GMV reduction in the right cerebellum, bilateral hippocampus, left insula, right superior temporal gyrus, left anterior cingulate gyrus, bilateral caudate nucleus and right middle frontal gyrus. Furthermore, there was a significant negative correlation between the local GMV of the right cerebellar hemisphere and OABSS score. CONCLUSIONS: Patients with OAB have abnormal GMV in brain regions localized within the brain-bladder control network. It deepens our understanding of the structural changes in the brain area of the network. The patterns of structural reorganization in patients with OAB may provide useful information in the neuropathological mechanisms of the OAB.


Assuntos
Substância Cinzenta/patologia , Bexiga Urinária Hiperativa/complicações , Adulto , Atrofia/complicações , Atrofia/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Correlação de Dados , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Estudos Prospectivos , Adulto Jovem
7.
Neuroimage Clin ; 28: 102425, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32979843

RESUMO

Agenesis of the corpus callosum (AgCC) is a rare congenital malformation characterized by partial or complete absence of the corpus callosum (CC). The effects of AgCC on cerebral structural and functional networks are not clear. We aimed to utilize AgCC as a model to characterize the relationship between brain structure and function. Diffusion tensor imaging and resting-state fMRI data were collected from nine AgCC and ten healthy subjects. The interhemispheric functional connectivity (FC) was quantified using a voxel-mirrored-homotopic-connectivity (VMHC) method, and its correlation with the number (FN) and fractional anisotropy (FA) of the fibers crossing the CC was calculated. Graph-based network analyses of structural and functional topologic properties were performed. AgCC subjects showed markedly reduced VMHC compared to controls. VMHC was significantly correlated with the FN and FA of the fibers crossing the CC. Structural network analyses revealed impaired global properties, but intact local properties in AgCC compared to controls. Functional network analyses showed no significant difference in network properties between the groups. Finally, in both groups, brain areas with more fiber connections were more likely to build a positive FC with each other, while areas with decreased white matter connections were more likely to result in negative FC. Our observations demonstrate that interhemispheric FC is highly dependent on CC structure. Increased alternative intrahemispheric SC might be a compensatory mechanism in AgCC that helps to maintain normal global brain function. Our study provides insights into the underlying neurological pathophysiology of brain malformations, thereby helping to elucidate the structure-function relationship of normal human brain.


Assuntos
Corpo Caloso , Imagem de Tensor de Difusão , Agenesia do Corpo Caloso/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Corpo Caloso/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética
8.
World J Urol ; 38(4): 1027-1034, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31172280

RESUMO

PURPOSE: This study aims to determine whether intra-network and inter-network brain connectivities are altered using an independent component analysis (ICA). METHODS: Resting-state functional MRI (rs-fMRI) data were acquired from 26 patients with OAB and 28 healthy controls (HC). Eleven resting-state networks (RSNs) were identified via ICA. General linear model (GLM) was used to compare intra-network FC and inter-network FC of RSNs between the two groups. Pearson correlation analyses were performed to investigate the relationship between the identified RSNs and clinical variables. RESULTS: Compared with HC, the OAB group showed abnormal FC within the sensorimotor-related network (SMN), the dorsal attention network (DAN), the dorsal visual network (dVN), and the left frontoparietal network (LFPN). With respect to inter-network interactions, decreased FC was detected between the SMN and the anterior default mode network (aDMN). CONCLUSION: This study demonstrated that abnormal FC between RSNs may reflect the altered resting state of the brain-bladder network. The findings of this study provide complementary evidence that can help further understand the neural substrates of the overactive bladder.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética , Rede Nervosa/diagnóstico por imagem , Bexiga Urinária Hiperativa/diagnóstico por imagem , Adulto , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Síndrome
9.
Psychiatry Res Neuroimaging ; 293: 110987, 2019 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-31629132

RESUMO

Prospection, which has a close relationship with motivation and goal-directed behavior, could be a potential target for alleviating negative symptoms. The present study aimed to examine the structural neural correlates of prospection impairments and the involvement of working memory in prospection in schizophrenia patients. Thirty-seven patients with schizophrenia and 28 healthy controls were recruited and all of them completed a prospection task. Working memory was assessed with the Letter Number Span test. In addition, all participants underwent a structural MRI scan. Voxel-based morphometry (VBM) analysis was used to measure grey matter (GM) volume. We found that in schizophrenia patients, GM loss in the right lateral prefrontal cortex (PFC) and the right ventral medial PFC was correlated with decreased internal details in the prospection task. Moreover, GM volume of the right lateral PFC was found to mediate the relationship between working memory and internal details in these patients. In conclusion, GM loss in the PFC is associated with prospection impairments in schizophrenia patients. Working memory deficits may partially account for prospection impairments in schizophrenia patients.


Assuntos
Memória de Curto Prazo/fisiologia , Esquizofrenia/fisiopatologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtornos da Memória/diagnóstico por imagem , Transtornos da Memória/fisiopatologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Esquizofrenia/diagnóstico por imagem
10.
Urology ; 131: 64-70, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31150692

RESUMO

OBJECTIVE: To investigate the whole-brain functional connectivity strength (FCS) of patients with the overactive bladder syndrome (OAB). METHODS: This study investigates the changes of intrinsic whole brain functional connectivity pattern in OAB using FCS. We acquired resting-state fMRI data from 26 OAB patients and 28 healthy controls. FCS was used to compute the long-range and short-range FCS values for each voxel in the brain of each subject. The long or short-range FCS maps were compared between OAB patients and healthy controls. Pearson's correlation coefficients was also performed between abnormal FCS regions and clinical/psychometric scores in patients. RESULTS: Compared with healthy control subjects, the OAB patients exhibited significantly decreased short-range FCS in the right medial superior frontal gyrus and bilateral anterior cingulate gyrus, and increased short-range FCS in the middle frontal gyrus, the precentral gyrus, and bilateral caudate nucleus. In addition, significantly decreased long-range FCS was found in bilateral middle cingulate gyrus and posterior cingulate gyrus. Furthermore, the abnormal FCS values in the right caudate nucleus showed significantly negative correlation with Self-Rating Depression Scale of OAB patients. CONCLUSION: Patients with OAB have abnormal short-range and long-range FCS in brain regions associated with brain-bladder network. Our study provides new insights into the underlying brain network topology of OAB.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Imageamento por Ressonância Magnética , Bexiga Urinária Hiperativa/diagnóstico por imagem , Bexiga Urinária Hiperativa/fisiopatologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Descanso , Síndrome
11.
Artigo em Inglês | MEDLINE | ID: mdl-30822447

RESUMO

BACKGROUND: Prospection, which is closely related to negative symptoms in patients with schizophrenia, is mainly associated with the Default Mode Network (DMN). Although abnormalities of the DMN have been reported in schizophrenia patients and at-risk individuals, little is known about the relationship between functional connectivity of the DMN and prospection in these clinical and subclinical populations. METHOD: Study 1 recruited 40 schizophrenia patients and 29 healthy controls, while 31 individuals with social anhedonia (SocAhn) and 28 controls participated in Study 2. Participants in both studies were asked to complete a prospection task and underwent resting-state functional MRI scans. Eleven regions of interest (ROIs) in the DMN were defined. Functional connectivity between each ROI and whole brain voxels were calculated and compared between groups (schizophrenia vs. control and SocAhn vs. control). Correlation analysis was conducted between altered functional connectivity and prospection variables in the schizophrenia and SocAhn groups. RESULTS: Schizophrenia patients showed both hyper-connectivity and hypo-connectivity at the medial temporal lobe (MTL) subsystem of the DMN. Decreased connectivity between the ventral medial prefrontal cortex (vMPFC) and the right superior temporal gyrus (rSTG) was correlated with poor thought/emotion details in prospection. In individuals with SocAhn, decreased connectivity between the retrosplenial cortex (Rsp), a region of the MTL subsystem, and the right fusiform gyrus, was found and this was correlated with their prospection performance. CONCLUSION: Altered functional connectivity of the key nodes of the MTL subsystem was found in both patients with schizophrenia and individuals with SocAhn. Moreover, hypo-connectivity of the vMPFC was found to be correlated with prospection impairments in schizophrenia patients.


Assuntos
Anedonia/fisiologia , Vias Neurais/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Esquizofrenia/fisiopatologia , Lobo Temporal/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
12.
Prion ; 12(5-6): 310-314, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30223705

RESUMO

Sporadic Creutzfeldt-Jakob disease (sCJD) is a fatal progressive neurodegenerative disease. Multimodal approaches, including electroencephalogram, diffusion-weighted imaging (DWI) of brain MRI, and cerebrospinal fluid biomarkers, have been applied to increase the diagnostic accuracy of sCJD. Although previous studies suggested DWI could be the most useful modality for sCJD diagnosis, whether metabolism changes underlying in sCJD are still poorly understood. To the best of our knowledge, there are only one case using the technique of arterial spin labeling (ASL) to detection and follow-up of perfusion changes in CJD. Herein, we described a 71-year-old woman presented with progressive cognitive decline, behavioral and psychological symptoms for two months. The patient died one month later after her admission. As far as we know, this is the first report using the combination of fluorodeoxyglucose positron emission tomography and ASL to explore the metabolism changes in sCJD. Our case exemplifies the difficulty clinicians may face in the diagnosis of sCJD.


Assuntos
Encéfalo/patologia , Síndrome de Creutzfeldt-Jakob/diagnóstico por imagem , Espectroscopia de Ressonância de Spin Eletrônica , Tomografia por Emissão de Pósitrons , Marcadores de Spin , Idoso , Biomarcadores/líquido cefalorraquidiano , Encéfalo/efeitos dos fármacos , Síndrome de Creutzfeldt-Jakob/líquido cefalorraquidiano , Síndrome de Creutzfeldt-Jakob/patologia , Eletroencefalografia , Evolução Fatal , Feminino , Fluordesoxiglucose F18/farmacologia , Humanos
13.
Quant Imaging Med Surg ; 8(11): 1113-1120, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30701165

RESUMO

BACKGROUND: This study aimed to assess the feasibility of deep learning-based magnetic resonance imaging (MRI) in the prediction of smoking status. METHODS: The head MRI 3D-T1WI images of 127 subjects (61 smokers and 66 non-smokers) were collected, and 176 image slices obtained for each subject. These subjects were 23-45 years old, and the smokers had at least 5 years of smoking experience. Approximate 25% of the subjects were randomly selected as the test set (15 smokers and 16 non-smokers), and the remaining subjects as the training set. Two deep learning models were developed: deep 3D convolutional neural network (Conv3D) and convolution neural network plus a recurrent neural network (RNN) with long short-term memory architecture (ConvLSTM). RESULTS: In the prediction of smoking status, Conv3D model achieved an accuracy of 80.6% (25/31), a sensitivity of 80.0% and a specificity of 81.3%, and ConvLSTM model achieved an accuracy of 93.5% (29/31), a sensitivity of 93.33% and a specificity of 93.75%. The accuracy obtained by these methods was significantly higher than that (<70%) obtained with support vector machine (SVM) methods. CONCLUSIONS: The deep learning-based MRI can accurately predict smoking status. Studies with large sample size are needed to improve the accuracy and to predict the level of nicotine dependence.

14.
Neurol Res ; 39(12): 1094-1102, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28934078

RESUMO

Objectives Cigarette smoking is an important risk factor of central nervous system diseases. However, the white matter (WM) integrity of early adulthood chronic smokers has not been attached enough importance to as it deserves, and the relationship between the chronic smoking effect and the WM is still unclear. The purpose of this study was to investigate whole - brain WM microstructure of early adulthood smokers and explore the structural correlates of behaviorally relevant features of the disorder. Methods We compared multiple DTI-derived indices, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD), between early adulthood smokers (n = 19) and age-, education- and gender-matched controls (n = 23) using a whole-brain tract-based spatial statistics approach. We also explored the correlations of the mean DTI index values with pack-years and Fagerström Test for Nicotine Dependence. Results The smokers showed increased FA in left superior longitudinal fasciculus (SLF), left anterior corona radiate, left superior corona radiate, left posterior corona radiate, left external capsule (EC), left inferior fronto-occipital fasciculus and sagittal stratum (SS), and decreased RD in left SLF. There were significant negative correlations among the average FA in the left external capsule and pack-years in smokers. In addition, significant positive correlation was found between RD values in the left SLF and pack-years. Discussion These findings indicate that smokers show microstructural changes in several white-matter regions. The correlation between the cumulative effect and microstructural WM alternations suggests that WM properties may become the new biomarkers in practice.


Assuntos
Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão , Fumar/patologia , Substância Branca/diagnóstico por imagem , Adulto , Encéfalo/patologia , Estudos Transversais , Interpretação Estatística de Dados , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Fumantes , Substância Branca/patologia
15.
Eur Neurol ; 78(1-2): 41-47, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28618415

RESUMO

BACKGROUND: We aimed to explore the relation between the microstructural integrity of white matter using the technique of diffusion tensor imaging (DTI) and changes of cognition in leukoaraiosis (LA). METHODS: Fifty patients with LA and 50 age- and gender-matched controls were recruited consecutively. The average values of mean diffusivity (MD) and fractional anisotropy (FA) were quantified both within white matter lesions (WMLs) and normal-appearing white matter (NAWM) from the regions of interest (ROIs). RESULTS: We found significantly decreased FA and increased MD in WMLs at the 5 ROIs than that in NAWM and controls (p < 0.05). The values of FA in NAWM were significantly lower at centrum semiovale and posterior periventricular white matter than those of controls (p < 0.05). The values of MD in NAWM were significantly higher at the anterior periventricular white matter and corpus callosum than those of controls (p < 0.05). The values of FA in NAWM located at anterior periventricular white matter correlated inversely with the Z scores of executive function (r = -0.420, p = 0.028). CONCLUSIONS: DTI may provide some important information about the cognitive dysfunction in patients with LA, which may largely attribute to the "disconnection" of cortico-subcortical pathways, with the evidence of reduced FA and increased MD.


Assuntos
Disfunção Cognitiva/patologia , Imagem de Tensor de Difusão/métodos , Leucoaraiose/patologia , Vias Neurais/patologia , Substância Branca/patologia , Adulto , Anisotropia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Feminino , Humanos , Leucoaraiose/complicações , Leucoaraiose/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
16.
BMC Neurol ; 17(1): 103, 2017 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-28545419

RESUMO

BACKGROUND: Mild encephalitis/encephalopathy with reversible splenial lesion (MERS) is a rare clinico-radiological entity characterized by the magnetic resonance imaging (MRI) finding of a reversible lesion in the corpus callosum, sometimes involved the symmetrical white matters. Many cases of child-onset MERS with various causes have been reported. However, adult-onset MERS is relatively rare. The clinical characteristics and pathophysiologiccal mechanisms of adult-onset MERS are not well understood. We reviewed the literature on adult-onset MERS in order to describe the characteristics of MERS in adults and to provide experiences for clinician. METHODS: We reported a case of adult-onset MERS with acute urinary retension and performed literature search from PubMed and web of science databases to identify other adult-onset MERS reports from Januarary 2004 to March 2016. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was followed on selection process. And then we summarized the clinico-radiological features of adult-onset MERS. RESULTS: Twenty-nine adult-onset MERS cases were reviewed from available literature including the case we have. 86.2% of the cases (25/29) were reported in Asia, especially in Japan. Ages varied between 18 and 59 years old with a 12:17 female-to-male ratio. The major cause was infection by virus or bacteria. Fever and headache were the most common clinical manifestation, and acute urinary retention was observed in 6 patients. All patients recovered completely within a month. CONCLUSION: Adult-onset MERS is an entity with a broad clinico-radiological spectrum because of the various diseases and conditions. There are similar characteristics between MERS in adults and children, also some differences.


Assuntos
Encefalopatias/diagnóstico , Corpo Caloso/patologia , Encefalite/diagnóstico , Adulto , Encefalopatias/complicações , Encefalopatias/diagnóstico por imagem , Encefalopatias/patologia , Encefalite/complicações , Encefalite/diagnóstico por imagem , Encefalite/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Prognóstico , Adulto Jovem
17.
Medicine (Baltimore) ; 96(17): e6703, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28445276

RESUMO

Our study aimed to investigate the changes of white matter microstructure of cortico-subcortical pathways using diffusion tensor imaging (DTI), and to explore the relationship between abnormal parameters of DTI and cognitive function underlying in patients with leukoaraiosis (LA).A total of 42 patients with LA and 42 age- and sex-matched healthy controls were recruited from Beijing Chaoyang Hospital, Capital Medical University between January 2012 and December 2012. All the subjects underwent scans of conventional magnetic resonance imaging and DTI, and a comprehensive neuropsychological battery was utilized. The regions of interest (ROIs) were located at the white matter of centrum semiovale, anterior and posterior periventricular white matter, basal ganglia, corpus callosum. The averaged values of mean diffusivity (MD) and fractional anisotropy (FA) were quantified both within white matter lesions (WMLs) and normal appearing white matter (NAWM). A linear regression analysis was performed to assess the association between diffusion parameters and decline in cognitive domains.Patients with LA were associated with comprehensive cognitive function deficits. We found that significantly decreased FA and increased MD in WMLs at the 5 ROIs than that of NAWM and controls (P < .05). The values of FA in NAWM were significantly lower and MD in NAWM were significantly higher at centrum semiovale and posterior periventricular white matter than that of controls (P < .05). The values of FA in WMLs at anterior periventricular white matter were positively related to the performances of cognition in patients with LA (P < .05). The values of FA in NAWM located at anterior periventricular white matter were positively related to the score of Digit-symbol test (r = 0.446, P = .002). The values of FA in NAWM located at anterior periventricular white matter correlated inversely with the Z scores of executive function (r = -0.418, P = .03).In our study, patients with LA exhibited significant cognitive impairment especially in the domains of executive function. The technique of DTI revealed that the reduced FA and increased MD at the corresponding regions of cortico-subcortical pathways in patients with LA. DTI may be of great help for an early pathology of white matter microstructure underlying in patients with LA.


Assuntos
Disfunção Cognitiva/diagnóstico por imagem , Corpo Estriado/diagnóstico por imagem , Leucoaraiose/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Idoso , Cognição , Disfunção Cognitiva/etiologia , Imagem de Tensor de Difusão , Feminino , Humanos , Leucoaraiose/complicações , Leucoaraiose/psicologia , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Testes Neuropsicológicos , Substância Branca/diagnóstico por imagem
18.
Neurol Sci ; 38(7): 1279-1286, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28439672

RESUMO

Agenesis of the corpus callosum (AgCC) can result in subtle to severe cognitive deficits. Individuals with impaired cognition often show abnormalities on resting-state functional magnetic resonance imaging (rs-fMRI). This study used rs-fMRI to investigate changes in regional homogeneity (ReHo) and functional connectivity (FC) among individuals with AgCC. AgCC individuals (n = 10) and age-, sex-, and education-matched healthy control subjects (n = 19) were included in this study. The ReHo values were calculated to represent spontaneous brain activity. The regions which showed altered ReHo were selected as seeds to compare FC with the whole brain between the AgCC group and the healthy control group. Compared with healthy control subjects, the AgCC individuals had increased ReHo in the left anterior cingulate gyrus, left rolandic operculum, and right precuneus and decreased ReHo in the right calcarine, right cingual gyrus and right cuneus gyrus. The right calcarine and the right lingual gyrus in the AgCC exhibited decreased FC with bilateral cuneus, superior occipital gyrus, Rolandic operculum, superior temporal gyrus, posterior central gyrus, and midcingulate gyrus.The right cuneus gyrus in the AgCC individuals exhibited decreased FC with the bilateral calcarine gyrus, left cuneus, and left superior occipital gyrus. Our study revealed several subareas within the visual cortex exhibited remarkable abnormalities of spontaneous brain activity and decreased FC with the higher-order cognitive cortex.The abnormalities of ReHo and FC in AgCC individuals may provide new insights into the neurological pathophysiology.


Assuntos
Disfunção Cognitiva/fisiopatologia , Corpo Caloso/patologia , Imageamento por Ressonância Magnética , Adulto , Idoso , Mapeamento Encefálico/métodos , Córtex Cerebral/fisiopatologia , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Lobo Parietal/fisiopatologia , Córtex Visual/fisiopatologia
19.
Respirology ; 22(6): 1118-1124, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28374936

RESUMO

BACKGROUND AND OBJECTIVE: Smoking is a leading cause of death in the world. Aberrant brain function has been repeatedly linked to tobacco smoking. However, little is known about insula-based resting-state functional connectivity (rsFC) in non-deprived tobacco-dependent smokers. This study characterized the correlation between insula-based rsFC and tobacco dependence severity in non-deprived smokers. METHODS: A total of 37 male smokers and 37 age-matched male non-smokers completed resting-state functional MRI (fMRI) scans. The insula-based rsFC differences between smokers and controls were investigated and the correlation between insula-based rsFC and FTND (Fagerström Test for Nicotine Dependence) scores were then assessed. RESULTS: Compared with controls, smokers showed significantly lower rsFC between orbitofrontal cortex, superior frontal gyrus, temporal lobe and insula. The rsFC between orbitofrontal cortex, temporal lobe, inferior parietal cortex, occipital lobe and insula was positively correlated with FTND. However, the rsFC between anterior cingulate cortex and insula was negatively correlated with FTND. CONCLUSION: Our findings suggest differences in brain functional connectivity between smokers and non-smokers. This study sheds new insights into the neural mechanisms of tobacco dependence.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Imageamento por Ressonância Magnética , Fumar Tabaco/fisiopatologia , Tabagismo/diagnóstico por imagem , Tabagismo/fisiopatologia , Adulto , Estudos de Casos e Controles , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Masculino , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/fisiopatologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiopatologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Descanso/fisiologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiopatologia , Adulto Jovem
20.
Clin Respir J ; 11(5): 621-631, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26404024

RESUMO

INTRODUCTION: Many studies have reported brain volume changes in smokers. However, the volume differences of grey matter (GM) and white matter (WM) in young and middle-aged male smokers with different lifetime tobacco consumption (pack-years) remain uncertain. OBJECTIVES: To examine the brain volume change, especially whether more pack-years smoking would be associated with smaller gray matter and white matter volume in young and middle-aged male smokers. METHODS: We used a 3T MR scanner and performed Diffeomorphic anatomical registration through exponentiated lie algebra (DARTEL)-based voxel-based morphometry on 53 long-term male smokers (30.72 ± 4.19 years) and 53 male healthy non-smokers (30.83 ± 5.18 years). We separated smokers to light and heavy smokers by pack-years and compared brain volume between different smoker groups and non-smokers. And then we did analysis of covariance (ANCOVA) between smokers and non-smokers by setting pack-years as covariates. RESULTS: Light and heavy smokers all displayed smaller GM and WM volume than non-smokers and more obviously in heavy smokers. The main smaller areas in light and heavy smokers were superior temporal gyrus, insula, middle occipital gyrus, posterior cingulate, precuneus in GM and posterior cingulate, thalamus and midbrain in WM, in addition, we also observed more pack-years smoking was associated with some certain smaller GM and WM volumes by ANCOVA. CONCLUSION: Young and middle-aged male smokers had many smaller brain areas than non-smokers. Some of these areas' volume had negative correlation with pack-years, while some had not. These may due to different pathophysiological role of smokings.


Assuntos
Encéfalo/patologia , Substância Cinzenta/patologia , Substância Branca/patologia , Adulto , Algoritmos , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Masculino , Tamanho do Órgão , Fumantes , Uso de Tabaco/efeitos adversos , Uso de Tabaco/tendências , Substância Branca/diagnóstico por imagem , Adulto Jovem
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