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1.
Acta Neuropathol Commun ; 12(1): 66, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654316

RESUMO

The elderly frequently present impaired blood-brain barrier which is closely associated with various neurodegenerative diseases. However, how the albumin, the most abundant protein in the plasma, leaking through the disrupted BBB, contributes to the neuropathology remains poorly understood. We here demonstrated that mouse serum albumin-activated microglia induced astrocytes to A1 phenotype to remarkably increase levels of Elovl1, an astrocytic synthase for very long-chain saturated fatty acids, significantly promoting VLSFAs secretion and causing neuronal lippoapoptosis through endoplasmic reticulum stress response pathway. Moreover, MSA-activated microglia triggered remarkable tau phosphorylation at multiple sites through NLRP3 inflammasome pathway. Intracerebroventricular injection of MSA into the brains of C57BL/6J mice to a similar concentration as in patient brains induced neuronal apoptosis, neuroinflammation, increased tau phosphorylation, and decreased the spatial learning and memory abilities, while Elovl1 knockdown significantly prevented the deleterious effect of MSA. Overall, our study here revealed that MSA induced tau phosphorylation and neuron apoptosis based on MSA-activated microglia and astrocytes, respectively, showing the critical roles of MSA in initiating the occurrence of tauopathies and cognitive decline, and providing potential therapeutic targets for MSA-induced neuropathology in multiple neurodegenerative disorders.


Assuntos
Apoptose , Camundongos Endogâmicos C57BL , Neurônios , Albumina Sérica , Tauopatias , Animais , Humanos , Masculino , Camundongos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Astrócitos/metabolismo , Astrócitos/patologia , Astrócitos/efeitos dos fármacos , Elongases de Ácidos Graxos/metabolismo , Microglia/metabolismo , Microglia/efeitos dos fármacos , Microglia/patologia , Neurônios/metabolismo , Neurônios/patologia , Neurônios/efeitos dos fármacos , Albumina Sérica/metabolismo , Albumina Sérica/farmacologia , Proteínas tau/metabolismo , Tauopatias/patologia , Tauopatias/metabolismo
2.
Transl Vis Sci Technol ; 12(11): 22, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37975841

RESUMO

Purpose: To develop and validate a fully automated deep-learning-based tool for segmentation of the human eyeball using a three-dimensional (3D) U-Net, compare its performance to semiautomatic segmentation ground truth and a two-dimensional (2D) U-Net, and analyze age and sex differences in eyeball volume, as well as gaze-dependent volume consistency in normal subjects. Methods: We retrospectively collected 474 magnetic resonance imaging (MRI) scans, including different gazing scans, from 119 patients. A 10-fold cross-validation was applied to separate the dataset into training, test, and validation sets for both the 3D U-Net and 2D U-Net. Performance accuracy was measured using four quantitative metrics compared to the ground truth, and Bland-Altman plot analysis was conducted. Age and sex differences in eyeball volume and variability in eyeball volume differences across gazing directions were analyzed. Results: The 3D U-Net outperformed the 2D U-Net with mean accuracy scores >0.95, showing acceptable agreement in the Bland-Altman plot analysis despite a tendency for slight overestimation (mean difference = -0.172 cm³). Significant sex differences and age effects on eyeball volume were observed for both methods (P < 0.05). No significant volume differences were found between the segmentation methods or within each method for the different gazing directions. Significant differences in performance accuracy were identified among the five gazing directions, with the upward direction showing a notably lower performance. Conclusions: Our study demonstrated the effectiveness of 3D U-Net human eyeball volume segmentation using T2-weighted MRI. The robustness and reliability of 3D U-Net across diverse populations and gaze directions support enhanced ophthalmic diagnosis and treatment strategies. Translational Relevance: Our findings demonstrate the feasibility of using the proposed 3D U-Net model for the automatic segmentation of the human eyeball, with potential applications in various ophthalmic research fields that require the analysis of 3D geometric eye globe shapes or eye movement detection.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Processamento de Imagem Assistida por Computador/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos
3.
J Korean Soc Radiol ; 84(3): 638-652, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37325007

RESUMO

Purpose: To investigate the MRI markers for the prediction of amyloid ß (Aß)-positivity in mild cognitive impairment (MCI) and Alzheimer's disease (AD), and to evaluate the differences in MRI markers between Aß-positive (Aß [+]) and -negative groups using the machine learning (ML) method. Materials and Methods: This study included 139 patients with MCI and AD who underwent amyloid PET-CT and brain MRI. Patients were divided into Aß (+) (n = 84) and Aß-negative (n = 55) groups. Visual analysis was performed with the Fazekas scale of white matter hyperintensity (WMH) and cerebral microbleeds (CMB) scores. The WMH volume and regional brain volume were quantitatively measured. The multivariable logistic regression and ML using support vector machine, and logistic regression were used to identify the best MRI predictors of Aß-positivity. Results: The Fazekas scale of WMH (p = 0.02) and CMB scores (p = 0.04) were higher in Aß (+). The volumes of hippocampus, entorhinal cortex, and precuneus were smaller in Aß (+) (p < 0.05). The third ventricle volume was larger in Aß (+) (p = 0.002). The logistic regression of ML showed a good accuracy (81.1%) with mini-mental state examination (MMSE) and regional brain volumes. Conclusion: The application of ML using the MMSE, third ventricle, and hippocampal volume is helpful in predicting Aß-positivity with a good accuracy.

4.
J Autism Dev Disord ; 53(1): 25-37, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34984638

RESUMO

Multimodal imaging studies targeting preschoolers and low-functioning autism spectrum disorder (ASD) patients are scarce. We applied machine learning classifiers to parameters from T1-weighted MRI and DTI data of 58 children with ASD (age 3-6 years) and 48 typically developing controls (TDC). Classification performance reached an accuracy, sensitivity, and specificity of 88.8%, 93.0%, and 83.8%, respectively. The most prominent features were the cortical thickness of the right inferior occipital gyrus, mean diffusivity of the middle cerebellar peduncle, and nodal efficiency of the left posterior cingulate gyrus. Machine learning-based analysis of MRI data was useful in distinguishing low-functioning ASD preschoolers from TDCs. Combination of T1 and DTI improved classification accuracy about 10%, and large-scale multi-modal MRI studies are warranted for external validation.


Assuntos
Transtorno do Espectro Autista , Criança , Humanos , Pré-Escolar , Transtorno do Espectro Autista/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Imageamento por Ressonância Magnética/métodos , Lobo Occipital , Aprendizado de Máquina , Encéfalo/diagnóstico por imagem
5.
ACS Nano ; 16(8): 12036-12048, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35881002

RESUMO

Cancer immunotherapy efficacy is largely limited by the suppressive tumor immune microenvironment (TIME) where antitumor immune cells are inhibited and tumor antigens continue to mutate or be lost. To remodel the TIME, we here applied weakly alkaline layered double hydroxide nanoparticles (LDH NPs) to neutralize the excess acid and block autophagy of tumor cells for neoadjuvant cancer immunotherapy. Peritumoral injection of LDH NPs provided a long-term and efficient acid-neutralization in the TIME, blocked the lysosome-mediated autophagy pathway in tumor cells, and increased the levels of antitumor tumor-associated macrophages and T cells. These LDH NPs captured tumor antigens released in the tumor tissues and effectively inhibited the growth of both melanoma and colon tumors in vivo. These findings indicate that LDH NPs, as an immunomodulator and adjuvant, successfully "awaken" and promote the host innate and adaptive immune systems, showing promising potential for solid tumor immunotherapy.


Assuntos
Hidróxidos , Nanopartículas , Linhagem Celular Tumoral , Imunoterapia , Autofagia , Adjuvantes Imunológicos , Microambiente Tumoral , Antígenos de Neoplasias
6.
Sci Rep ; 12(1): 12103, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35840614

RESUMO

The aim of this study is to quantitatively investigate the microstructural properties of the optic nerve (ON) in vivo using diffusion tensor imaging (DTI) in patients with unilateral optic atrophy (OA) and to determine their association with retinal nerve fiber layer (RNFL) thickness of the optic nerve head (ONH). Six patients with unilateral OA and 11 control subjects underwent DTI. ONs from ONH to the orbital apex were tracked. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were computed in both ONs and their correlation with RNFL thickness measured using optical coherence tomography was also analyzed. FA of atrophic ON was lower than that of non-affected and control ONs (atrophic [A], 0.136 ± 0.059; non-affected [N], 0.384 ± 0.048; control [C], 0.389 ± 0.053). MD and RD of atrophic ONs were higher than those of non-affected and control ONs (MD, A, 0.988 ± 0.247; N, 0.658 ± 0.058; C, 0.687 ± 0.079; RD, A, 0.920 ± 0.247; N, 0.510 ± 0.054; C, 0.532 ± 0.078). All DTI measures of atrophic ON except for AD showed a significant correlation with RNFL thickness of ONH; FA showed the strongest correlation, followed by RD and MD (FA, R2 = 0.936, P < 0.001; RD, R2 = 0.795, P < 0.001; MD, R2 = 0.655, P = 0.001). This study reports quantitative analysis of the ON using DTI and differences in DTI measures between atrophic and normal ONs. The significant correlation between DTI measures and RNFL thickness suggests the applicability of DTI as a clinical tool to evaluate the ON.


Assuntos
Atrofia Óptica , Doenças do Nervo Óptico , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Humanos , Atrofia Óptica/diagnóstico por imagem , Nervo Óptico/diagnóstico por imagem
7.
Front Neurol ; 12: 680488, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630272

RESUMO

Purpose: To quantitatively investigate the microstructural properties of the optic nerve (ON) in vivo using diffusion magnetic resonance imaging (dMRI) tractography in an elderly population and to determine the differences between the ON diffusion properties stratified by basic demographics. Methods: We measured fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD) of the intraorbital ON in cognitively normal controls selected from the Alzheimer's Disease Neuroimaging Initiative 3 database (n =104; mean age = 73. 8 ± 8.1 years) using dMRI probabilistic tractography and evaluated the correlation between diffusion parameters and demographic factors. Diffusion parameters were measured in 20 equidistant nodes along the tract, and the data from proximal 70% (14 nodes) of the intraorbital ON were averaged. Results: The mean FA of the intraorbital ON was 0.392 ± 0.063, and the mean MD was 1.163 ± 0.165 µm2/s. The mean RD was 0.882 ± 0.152 µm2/s, and the mean AD was 1.693 ± 0.183 µm2/s. The multiple linear regression model showed a negative correlation between FA and age. FA in females was significantly higher than males, whereas RD in female was significantly lower. Conclusions: We measured the diffusion properties of the intraorbital ON using dMRI tractography in an elderly cognitively normal population. The diffusion properties detected by dMRI tractography may substantially reflect the microstructure of the ON.

8.
Transl Vis Sci Technol ; 10(11): 20, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34570191

RESUMO

Purpose: To evaluate the eyeball rotation during lateral gaze in patients with intermittent exotropia (IXT) using three-dimensional magnetic resonance imaging (MRI). Methods: In this prospective observational study, patients with IXT (n = 29) underwent orbital MRI during central, right, and left gazes. Fixation targets were placed at a 40° angle for lateral gaze. After acquisition of MR images, the position of the static tissues other than the eyeball in the MR images were matched three-dimensionally. The optical axis was defined as the perpendicular line to its lens passing through the corneal vertex. The rotation angle was measured as the angle between optical axes in central gaze and lateral gaze using ImageJ. A difference of 3° or more in the rotational angle between both eyes was considered a significant difference. Results: Eight patients (26.7%) had a larger adduction angle than the abduction angle of the fellow eye and six patients (20.0%) showed a smaller adduction angle during lateral gaze on at least one side. There was no significant factor associated with the pattern of rotation. Conclusions: Almost one-half of the patients with IXT had significant difference in the rotation angle between both eyes during lateral gaze. Measurement of the rotation angle during lateral gaze using MRI showed that IXT is not a perfectly comitant disturbance of gaze in some subjects. Translational Relevance: Quantitative analysis for eye movements using MRI can provide useful information for physiologic mechanism and proper surgical planning in patients with IXT.


Assuntos
Exotropia , Exotropia/diagnóstico por imagem , Movimentos Oculares , Humanos , Imageamento por Ressonância Magnética , Músculos Oculomotores/diagnóstico por imagem , Rotação
9.
Int J Clin Exp Pathol ; 14(8): 875-880, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34527130

RESUMO

Primary small cell carcinoma (SCC) of the brain is rare, and there have been no reports of small cell carcinoma located at the resection site of a glioma without extracranial tumours. Herein, we report a case of brain SCC in the same intracranial region from which a malignant glioma had been surgically resected a year prior. The patient, a 68-year-old male, had headaches as a symptom, and brain CT and MRI revealed a hyperdense region measuring 5.5×5 centimetres. Blood test results showed no significant changes. H&E staining suggested that these tumour cells had the characteristics of small cell lung carcinoma cells. Immunohistochemical staining for the glioma marker S100 was negative, but immunohistochemical staining for the neuroendocrine marker synaptophysin and for the cell adhesion molecule CD56 was strongly positive; meanwhile, staining for thyroid transcription factor-1 (TTF-1), a relatively specific marker of lung and thyroid carcinoma, was positive, and the Ki67 index was 75%. The pathological examination strongly suggested that the tumour was a small cell lung carcinoma, but CT and MRI scans indicated that there were no extracranial tumours. Hence, the tumour could be a primary small cell brain carcinoma. The patient underwent surgical resection again; the excised tumour was a mass of grey and white tissues with fragmentary morphology, and its dimensions were 3.0 cm×1.5 cm×0.8 cm.

10.
Brain Behav ; 11(5): e02112, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33792194

RESUMO

OBJECTIVE: We evaluated disruption of the white matter (WM) network related with Alzheimer's disease (AD) and Lewy body disease (LBD), which includes Parkinson's disease and dementia with Lewy bodies. METHODS: We consecutively recruited 37 controls and 77 patients with AD-related cognitive impairment (ADCI) and/or LBD-related cognitive impairment (LBCI). Diagnoses of ADCI and LBCI were supported by amyloid PET and dopamine transporter PET, respectively. There were 22 patients with ADCI, 19 patients with LBCI, and 36 patients with mixed ADCI/LBCI. We investigated the relationship between ADCI, LBCI, graph theory-based network measures on diffusion tensor images, and cognitive dysfunction using general linear models after controlling for age, sex, education, deep WM hyperintensities (WMH), periventricular WMH, and intracranial volume. RESULTS: LBCI, especially mixed with ADCI, was associated with increased normalized path length and decreased normalized global efficiency. LBCI was related to the decreased nodal degree of left caudate, which was further associated with broad cognitive dysfunction. Decreased left caudate nodal degree was associated with decreased fractional anisotropy (FA) in the brain regions vulnerable to LBD. Compared with the control group, the LBCI group had an increased betweenness centrality in the occipital nodes, which was associated with decreased FA in the WM adjacent to the striatum and visuospatial dysfunction. CONCLUSION: Concomitant ADCI and LBCI are associated with the accentuation of LBCI-related WM network disruption centered in the left caudate nucleus. The increase of occipital betweenness centrality could be a characteristic biologic change associated with visuospatial dysfunction in LBCI.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença por Corpos de Lewy , Substância Branca , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Humanos , Doença por Corpos de Lewy/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
11.
RSC Adv ; 11(61): 38654-38666, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-35493257

RESUMO

Titanium dioxide, as a promising photocatalytic material, has attracted extensive attention in the field of photocatalytic degradation of organic pollutants in sewage. However, the photocatalytic performance needs to be further improved. In this work, fluorinated ZnO-TiO2 composites (F-ZTO) were prepared by a simple coprecipitation method. The photocatalytic performance of the samples was studied in detail with methyl orange as the target degradation product. The results indicated that under the same conditions, the degradation rates of 6% F-ZTO, F-TiO2 and TiO2 for methyl orange reached 93.75%, 76.56% and 62.89% respectively. This showed that the method used in this work could effectively improve the photocatalytic degradation performance of titanium dioxide. 6% F-ZTO showed an excellent photocatalytic activity, which was attributed to the small grain size, the large specific surface area and the effective inhibition of photoelectron-hole recombination due to fluorination and zinc oxide coupling. In three consecutive cycles, the photocatalytic activity was almost maintained, indicating that 6% F-ZTO had a good recycling performance.

12.
Sci Rep ; 10(1): 8905, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483122

RESUMO

Identification of EGFR mutations is critical to the treatment of primary lung cancer and brain metastases (BMs). Here, we explored whether radiomic features of contrast-enhanced T1-weighted images (T1WIs) of BMs predict EGFR mutation status in primary lung cancer cases. In total, 1209 features were extracted from the contrast-enhanced T1WIs of 61 patients with 210 measurable BMs. Feature selection and classification were optimized using several machine learning algorithms. Ten-fold cross-validation was applied to the T1WI BM dataset (189 BMs for training and 21 BMs for the test set). Area under receiver operating characteristic curves (AUC), accuracy, sensitivity, and specificity were calculated. Subgroup analyses were also performed according to metastasis size. For all measurable BMs, random forest (RF) classification with RF selection demonstrated the highest diagnostic performance for identifying EGFR mutation (AUC: 86.81). Support vector machine and AdaBoost were comparable to RF classification. Subgroup analyses revealed that small BMs had the highest AUC (89.09). The diagnostic performance for large BMs was lower than that for small BMs (the highest AUC: 78.22). Contrast-enhanced T1-weighted image radiomics of brain metastases predicted the EGFR mutation status of lung cancer BMs with good diagnostic performance. However, further study is necessary to apply this algorithm more widely and to larger BMs.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/secundário , Neoplasias Pulmonares/diagnóstico por imagem , Mutação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Idoso , Algoritmos , Área Sob a Curva , Neoplasias Encefálicas/genética , Meios de Contraste , Receptores ErbB/genética , Feminino , Humanos , Neoplasias Pulmonares/genética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Máquina de Vetores de Suporte
13.
J Alzheimers Dis ; 75(2): 531-545, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32310165

RESUMO

Alzheimer's disease (AD) is a common neurodegenerative disorder characterized by a heterogeneous distribution of pathological changes in the brain. Cortical thickness is one of the most sensitive imaging biomarkers for AD representing structural atrophy. The purpose of this study is to identify novel genes associated with cortical thickness. We measured the whole-brain mean cortical thickness from magnetic resonance imaging (MRI) scans in 919 subjects from the Alzheimer's Disease Neuroimaging Initiative cohort, including 163 AD patients, 488 mild cognitive impairment patients, and 268 cognitively normal participants. Based on the single-nucleotide polymorphism (SNP)-based genome-wide association study, we performed gene-based association analysis for mean cortical thickness. Furthermore, we performed expression quantitative trait loci, protein-protein interaction network, and pathway analysis to identify biologically functional information. We identified four genes (B4GALNT1, RAB44, LOC101927583, and SLC26A10), two pathways (cyclin-dependent protein kinase holoenzyme complex and nuclear cyclin-dependent protein kinase holoenzyme complex), and one protein-protein interaction (B4GALNT1 and GALNT8 pair). These genes are involved in protein degradation, GTPase activity, neuronal loss, and apoptosis. The identified pathways are involved in the cellular processes and neuronal differentiation, which contribute to neuronal loss that is responsible for AD. Furthermore, the most significant SNP (rs12320537) in B4GALNT1 is associated with expression levels of B4GALNT1 in several brain regions. Thus, the identified genes and pathways provide deeper mechanistic insight into the molecular basis of brain atrophy in AD.


Assuntos
Doença de Alzheimer/genética , Espessura Cortical do Cérebro , Endofenótipos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Progressão da Doença , Feminino , Marcadores Genéticos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Neuroimagem , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , RNA Longo não Codificante/genética
14.
Cancer Med ; 8(9): 4441-4453, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31218844

RESUMO

BACKGROUND: Recombinant human calcineurin B subunit (rhCNB) has been shown to be an immune-stimulatory protein promoting cytokine production and inducing phenotypic maturation of Dendritic cells (DCs). In vivo, it has good antitumor efficacy, and has potential as an antitumor drug. Exogenous rhCNB was found to be internalized into tumor cells via the Toll-like receptor 4 (TLR4) complex, but it was not known whether its immuno-modulatory and antitumor functions involved entry by this same route. METHODS: The production and secretion of the cytokines and chemokines in innate immune cells induced by rhCNB were determined by ELISA, and the expression of CD40, CD80, CD86, and MHCII was analyzed by FACs. Experimental Lewis lung cancer (LLC) model was prepared in C57 BL/6 wild-type (WT) mice, TLR4-/- mice or their littermates by the inoculation of LLCs in their right armpit, and then administrated daily intraperitoneal injections (0.2 mL) of normal saline, rhCNB 20 mg/kg, and rhCNB 40 mg/kg, respectively. RESULTS: Recombinant human calcineurin B subunit promoted the production of antitumor cytokines by innate immune cells, and culture supernatants of rhCNB-stimulated immune cells induced apoptosis of LLCs. In addition, rhCNB up-regulated CD40, CD80, CD86, and MHCII expression in macrophages and DCs in TLR4+ cells but failed to do so in TLR4 deficient cells. rhCNB also induced the formation of CD4+ and CD8+ T cells in splenocytes from WT mice, but not from TLR4-deficient littermates. Intraperitoneal administration of WT C57BL/6 mice with rhCNB resulted in a 50% reduction in LLC tumor growth, but failed to inhibit tumor growth in TLR4-/- littermates. CONCLUSIONS: The in vivo antitumor and immunomodulatory effects of rhCNB are mediated by the TLR4. This conclusion is important for the further understanding and development of rhCNB as an antitumor drug.


Assuntos
Antineoplásicos/administração & dosagem , Calcineurina/administração & dosagem , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Animais , Antineoplásicos/farmacologia , Calcineurina/genética , Calcineurina/farmacologia , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimiocinas/metabolismo , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Inativação de Genes , Humanos , Injeções Intraperitoneais , Camundongos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Pept Sci ; 25(6): e3159, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30843319

RESUMO

Calcineurin B subunit (CNB) is the regulatory subunit of calcineurin (CN), and its classical function is to regulate the activity of CN. Research in our laboratory has revealed that the recombinant human CNB (rhCNB) is a good antitumor candidate and can be internalized by tumor cells via TLR4 receptor complexes and targeted to tumor tissue in nude mice. However, the fragment or domain of rhCNB mediating internalization and target delivery has not been identified. To explore fragment- mediated rhCNB internalization and target delivery, we generated truncated derivatives of rhCNBs by recombinant DNA technology and examined their cellular uptake. Interactions between truncated rhCNBs and the TLR4 receptor were studied by ELISA and co-immunoprecipitation, and targeting of model tumors in nude mice was examined. The results showed that one truncated derivative, Trun3 (124-169aa), was taken up by cells and targeted tumors with almost the same efficiency as intact rhCNB. These results indicate that Trun3 (45aa) contains the major sequence responsible for rhCNB internalization and tumor targeting and might be developed for drug delivery to tumors.


Assuntos
Calcineurina/genética , Peptídeos/administração & dosagem , Receptor 4 Toll-Like/metabolismo , Animais , Calcineurina/química , Calcineurina/metabolismo , Linhagem Celular Tumoral , Células Hep G2 , Humanos , Camundongos , Camundongos Nus , Peptídeos/química , Peptídeos/genética , Peptídeos/farmacologia , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia
16.
Brain Behav ; 9(5): e01278, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30916450

RESUMO

BACKGROUND: Metamemory is the process of monitoring and controlling one's memory. Improving metamemory may reduce the memory problem in old age. We hypothesized that metamemory training (MMT) would improve cognition in older adults with subjective memory complaints and change the brain region related to metacognition. METHOD: We recruited and randomized older adults to the multi-strategic memory training of 10 weekly 90-min sessions, based on the metamemory concept or usual care. Cognitive tests including the Elderly Verbal Learning Test, Simple Rey Figure Test, Digit Span, Spatial Span, Categorical Fluency, and the Boston Naming Test were done in 201 participants, together with magnetic resonance imaging (MRI) in 49 participants before and after training. RESULTS: A total of 112 in the training group and 89 in the control group participated. The training group had a significant increase in long-term delayed free recall, categorical fluency, and the Boston Naming test. In MRI, the mean diffusivity of the bundles of axon tracts passing from the frontal lobe to the posterior end of the lateral sulcus decreased in the training group. CONCLUSION: These results indicate that the MMT program has a positive impact on enhancing older people' cognitive performance. Improved white matter integrity in the anterior and posterior cerebrum and increased cortical thickness of prefrontal regions, which related to metacognition, possibly suggest that the effects of the MMT would be induced via the enhancement of cognitive control.


Assuntos
Encéfalo/diagnóstico por imagem , Cognição/fisiologia , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética/métodos , Transtornos da Memória , Memória/fisiologia , Metacognição/fisiologia , Idoso , Idoso de 80 Anos ou mais , Autoavaliação Diagnóstica , Feminino , Humanos , Masculino , Transtornos da Memória/diagnóstico , Transtornos da Memória/psicologia
17.
J Alzheimers Dis ; 65(4): 1237-1246, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30149442

RESUMO

BACKGROUND/OBJECTIVE: In this study, we investigated a long-term trajectory of brain aging (from the 20 s to over-80) in cognitively normal (CN) individuals. We further determined whether differences in sex, education years, and apolipoprotein E ε 4 status affect age-related cortical thinning. METHODS: A total of 2,944 CN individuals who underwent high-resolution (3.0-Tesla) magnetic resonance imaging were included in this study. Cortical thickness was measured using a surface-based method. Multiple linear regression analyses were performed to evaluate age-related cortical thinning and related factors. RESULTS: Compared to those in their 20 s/30 s, participants in their 40 s showed thinning primarily in the medial and lateral frontal and inferior parietal regions, and cortical thinning occurred across most of the cortices with increasing age. Notably, the precuneus, inferior temporal and lateral occipital regions were relatively spared until later in life. Male and lower education years were associated with greater cortical thinning with distinct regional specificity. CONCLUSION: Our findings provide an important clue to understanding the mechanism of age-related cognitive decline and new strategies for preventing the acceleration of pathological brain aging.


Assuntos
Envelhecimento/fisiologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Apolipoproteína E4/genética , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Adulto Jovem
18.
Sci Rep ; 8(1): 5557, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29615677

RESUMO

We aimed to compare the longitudinal outcome of amnestic mild cognitive impairment (aMCI) patients with significant Pittsburgh Compound B uptake [PiB(+) aMCI] and those without [PiB(-) aMCI]. Cerebral ß-amyloid was measured in 47 patients with aMCI using PiB-positron emission tomography (PET) (31 PiB(+) aMCI and 16 PiB(-) aMCI). Clinical (N = 47) and neuropsychological follow-up (N = 37), and follow-up with brain magnetic resonance imaging (N = 38) and PiB-PET (N = 30) were performed for three years. PiB(+) aMCI had a higher risk of progression to dementia (hazard ratio = 3.74, 95% CI = 1.21-11.58) and faster rate of cortical thinning in the bilateral precuneus and right medial and lateral temporal cortices compared to PiB(-) aMCI. Among six PiB(-) aMCI patients who had regional PiB uptake ratio >1.5 in the posterior cingulate cortex (PCC), three (50.0%) progressed to dementia, and two of them had global PiB uptake ratio >1.5 at the follow-up PiB-PET. Our findings suggest that amyloid imaging is important for predicting the prognosis of aMCI patients, and that it is necessary to pay more attention to PiB(-) aMCI with increased regional PiB uptake in the PCC.


Assuntos
Amnésia/complicações , Amiloide/metabolismo , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/metabolismo , Idoso , Disfunção Cognitiva/complicações , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Masculino
19.
Sci Rep ; 8(1): 1095, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29348440

RESUMO

Previous studies have indicated that memory training may help older people improve cognition. However, evidence regarding who will benefit from such memory trainings has not been fully discovered yet. Understanding the clinical and neural inter-individual differences for predicting cognitive improvement is important for maximizing the training efficacy of memory-training programs. The purpose of this study was to find the individual characteristics and brain morphological characteristics that predict cognitive improvement after a multi-strategic memory training based on metamemory concept. Among a total of 49 older adults, 39 participated in the memory-training program and 10 did not. All of them underwent brain MRIs at the entry of the training and received the neuropsychological tests twice, before and after the training. Stepwise regression analysis showed that lower years of education predicted cognitive improvement in the training group. In MRI, thinner cortices of precuneus, cuneus and posterior cingulate gyrus and higher white matter anisotropy of the splenium of corpus callosum predicted cognitive improvement in the training group. Old age, lower education level and individual differences in cortical thickness and white matter microstructure of the episodic memory network may predict outcomes following multi-strategic training.


Assuntos
Cognição , Aprendizagem , Metacognição , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
20.
Oncotarget ; 8(39): 65876-65888, 2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-29029479

RESUMO

The calcineurin B subunit (CNB) has antitumor activity. We showed previously that recombinant human CNB (rhCNB) also had strong anti-tumor activity in vivo, and was thus a promising candidate anti-tumor drug. It appeared to kill tumor cells via immunomodulation. Here, we show that rhCNB inhibits the proliferation of human hepatoma HepG-2 cells, resulting in their apoptosis. Exogenous CNB was found to localize to mitochondria in tumor cells and activate the mitochondrial apoptosis pathway, as indicated by a decrease of mitochondrial transmembrane potential, release of cytochrome C and activation of caspase-9, which then activates caspase-3. At the same time Bcl-2 &Bcl-xL expression decreased, Bim expression increased, and Bax was activated. Interaction between rhCNB and Bcl-xL was detected, which may inhibit the function of Bcl-xL. Long-term tumor targeting was also observed in nude mice. These data deepened our understanding of the anti-tumor mechanism of rhCNB and provided guidance for its drug development.

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