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2.
Math Biosci Eng ; 16(5): 4382-4398, 2019 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-31499667

RESUMO

Due to both the hidden nature and the irreversibility of Alzheimers disease (AD), it has become the killer of the elderly and is thus the focus of much attention in the medical field. Radiologists compare the predicted brain age with the ground truth in order to provide a preliminary analysis of AD, which helps doctors diagnose AD as early in its development as possible. In this paper, a transfer learning-based method of predicting brain age using MR images and dataset of a public brain was proposed. In order to get the best transfer results, we froze different layers and only fine-tuned the remaining layers. We used three planes of brain MR images together to predict age for the first time and experiment results showed that the proposed method performs better than the state-of-the-art method under mean absolute error metric by 0.6 years. In addition, to explore the relationship between brain MR images of different planes and predicted age accuracy, we used three different planes of brain MR images to predict age respectively for the first time and found that sagittal plane MR images outperformed two other planes in age estimation. Finally, our research identified, the effective regions that contribute to brain age estimation for cognitively normal individuals and for AD patients with deep learning. For AD patients, the effective region is mainly concentrated in the frontal lobe of the brain, verifying the relevant medical conclusions about AD.

3.
Nat Neurosci ; 22(10): 1649-1658, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31451801

RESUMO

Comorbid depressive symptoms (CDS) in chronic pain are a common health problem, but the neural circuit mechanisms underlying these symptoms remain unclear. Here we identify a novel pathway involving 5-hydroxytryptamine (5-HT) projections from the dorsal raphe nucleus (5-HTDRN) to somatostatin (SOM)-expressing and non-SOM interneurons in the central nucleus of the amygdala (CeA). The SOMCeA neurons project directly to the lateral habenula, an area known involved in depression. Inhibition of the 5-HTDRN→SOMCeA pathway produced depression-like behavior in a male mouse model of chronic pain. Activation of this pathway using pharmacological or optogenetic approaches reduced depression-like behavior in these mice. Human functional magnetic resonance imaging data showed that compared to healthy controls, functional connectivity between the CeA-containing centromedial amygdala and the DRN was reduced in patients with CDS but not in patients in chronic pain without depression. These findings indicate that a novel 5-HTDRN→SOMCeA→lateral habenula pathway may mediate at least some aspects of CDS.


Assuntos
Dor Crônica/patologia , Depressão/patologia , Vias Neurais/patologia , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Animais , Comportamento Animal , Dor Crônica/complicações , Dor Crônica/diagnóstico por imagem , Depressão/complicações , Depressão/diagnóstico por imagem , Núcleo Dorsal da Rafe/diagnóstico por imagem , Núcleo Dorsal da Rafe/patologia , Feminino , Habenula/diagnóstico por imagem , Habenula/patologia , Humanos , Imagem por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Vias Neurais/diagnóstico por imagem , Neuralgia/diagnóstico por imagem , Neuralgia/patologia , Optogenética , Serotonina/metabolismo , Somatostatina/metabolismo
4.
Nanoscale ; 11(24): 11789-11807, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31184642

RESUMO

Autophagy may represent a common cellular response to nanomaterials. In the present study, it was demonstrated that zinc oxide nanoparticle (ZON)-elicited autophagy contributes to tumor cell killing by accelerating the intracellular dissolution of ZONs and reactive oxygen species (ROS) generation. In particular, ZONs could promote Atg5-regulated autophagy flux without the impairment of autophagosome-lysosome fusion, which is responsible for ZON-elicited cell death in cancer cells. On the other hand, a further study revealed that a significant free zinc ion release in lysosomal acid compartments and sequential ROS generation in cells treated with ZONs were also associated with tumor cytotoxicity. Intriguingly, the colocalization between FITC-labeled ZONs and autophagic vacuoles indicates that the intracellular fate of ZONs is associated with autophagy. Moreover, the chemical or genetic inhibition of autophagy significantly reduced the level of intracellular zinc ion release and ROS generation separately, demonstrating that ZON-induced autophagy contributed toward cancer cell death by accelerating zinc ion release and sequentially increasing intracellular ROS generation. The modulation of autophagy holds great promise for improving the efficacy of tumor chemotherapy. Herein, ZONs were verified to enhance chemotherapy in both normal and drug-resistant cancer cells via synergistic autophagy elicitation. Further, this elicitation resulted in tremendous zinc ion release and ROS generation, which accounted for enhancing the tumor chemotherapy and overcoming drug resistance. No obvious changes in the expression level of P-gp proteins or the amount of doxorubicin uptake induced by ZONs in MCF-7/ADR cells also indicated that the increased zinc ion release and ROS generation via synergistic autophagy induction were responsible for overcoming the drug resistance. Finally, in vivo experiments involving animal models of 4T1 tumor cells revealed that the antitumor therapeutic effect of a combinatory administration obviously outperformed those of ZONs or free doxorubicin treatment alone at the same dose, which could be attenuated by the autophagy inhibitor wortmannin or ion-chelating agent EDTA. Taken together, our results reveal the mechanism wherein the autophagy induction by ZONs potentiates cancer cell death and a novel biological application for ZONs in adjunct chemotherapy in which autophagy reinforces zinc ion release and ROS generation.


Assuntos
Antineoplásicos , Doxorrubicina , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Nanopartículas , Neoplasias Experimentais/tratamento farmacológico , Óxido de Zinco , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Feminino , Células HeLa , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Espécies Reativas de Oxigênio/metabolismo , Óxido de Zinco/química , Óxido de Zinco/farmacologia
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