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1.
J Chem Neuroanat ; 113: 101922, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33581266

RESUMO

Ample empirical evidence suggests that mitochondrial dysfunction and endoplasmic reticulum (ER) stress play a crucial role in the pathogenesis of Parkinson's disease (PD). Prohibitin (PHB), a mitochondrial inner-membrane protein involved in mitochondrial homeostasis and function, may be involved in the pathogenesis of PD. We investigated the functional role of PHB in mitochondrial biogenesis and ER stress in methyl-4-phenylpyridinium (MPP +)-induced in vivo and in vitro models of PD. The overexpression of PHB in SH-SY5Y cells block ed cell death and the apoptosis induced by MPP + incubation. PHB also block ed the activation of ER stress markers, including glucose-regulated protein 78, while increasing the expression of Xbox- binding protein 1 and caspase-12. Moreover, the intracerebroventricular administration of the PHB overexpression vector greatly block ed motor dysfunction and the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-mediated neurodegeneration in the mouse model of PD. The production of reactive oxygen species, ER stress, and autophagic stress induced by MPTP were also significantly block ed in PD mice overexpressing PHB. Our results suggest that PHB blocks the dopaminergic-neuron depletion by preserving mitochondrial function and inhibiting ER stress. The genetic manipulation of PHB may feature potential as a treatment for PD.


Assuntos
Apoptose/genética , Corpo Estriado/metabolismo , Neurônios Dopaminérgicos/metabolismo , Estresse do Retículo Endoplasmático/genética , Transtornos Parkinsonianos/metabolismo , Proteínas Repressoras/genética , Animais , Masculino , Camundongos , Proibitinas , Espécies Reativas de Oxigênio/metabolismo , Proteínas Repressoras/metabolismo , Substância Negra/metabolismo , alfa-Sinucleína/metabolismo
2.
PeerJ ; 8: e10056, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240590

RESUMO

Rhodioloside, the main effective constituent of Rhodiola rosea, demonstrates antiaging and antioxidative stress functions and inhibits calcium overloading in cells. These functions imply that rhodioloside may exert protective effects on hippocampal neurons after total cerebral ischemia/reperfusion injury. In this study, male Wistar rat models of total cerebral ischemia were constructed and randomly divided into four groups: sham-operation, ischemia/reperfusion, low-dosage, and high-dosage groups. The result showed that rhodioloside treatment reduced the apoptosis rates of hippocampal neurons and the histological grades of cone cells in the hippocampal CA1 region, but neuronal density was significantly increased. Besides, the protein expressions of Bcl-2/Bax and p53 were measured and found Bcl-2/Bax was increased and p53 protein level was reduced. Therefore, rhodioloside might have protective effects on rats with ischemia/reperfusion brain injury.

3.
IEEE Trans Vis Comput Graph ; 22(7): 1852-61, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26357400

RESUMO

Light fields (LFs) have been shown to enable photorealistic visualization of complex scenes. In practice, however, an LF tends to have a relatively small angular range or spatial resolution, which limits the scope of virtual navigation. In this paper, we show how seamless virtual navigation can be enhanced by stitching multiple LFs. Our technique consists of two key components: LF registration and LF stitching. To register LFs, we use what we call the ray-space motion matrix (RSMM) to establish pairwise ray-ray correspondences. Using Plücker coordinates, we show that the RSMM is a 5 ×6 matrix, which reduces to a 5 ×5 matrix under pure translation and/or in-plane rotation. The final LF stitching is done using multi-resolution, high-dimensional graph-cut in order to account for possible scene motion, imperfect RSMM estimation, and/or undersampling. We show how our technique allows us to create LFs with various enhanced features: extended horizontal and/or vertical field-of-view, larger synthetic aperture and defocus blur, and larger parallax.

4.
Stud Health Technol Inform ; 196: 479-85, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24732560

RESUMO

Providing real-time, interactive immersive surgical training has been a key research area in telemedicine. Earlier approaches have mainly adopted videotaped training that can only show imagery from a fixed view point. Recent advances on commodity 3D imaging have enabled a new paradigm for immersive surgical training by acquiring nearly complete 3D reconstructions of actual surgical procedures. However, unlike 2D videotaping that can easily stream data in real-time, by far 3D imaging based solutions require pre-capturing and processing the data; surgical trainings using the data have to be conducted offline after the acquisition. In this paper, we present a new real-time immersive 3D surgical training system. Our solution builds upon the recent multi-Kinect based surgical training system [1] that can acquire and display high delity 3D surgical procedures using only a small number of Microsoft Kinect sensors. We build on top of the system a client-server model for real-time streaming. On the server front, we efficiently fuse multiple Kinect data acquired from different viewpoints and compress and then stream the data to the client. On the client front, we build an interactive space-time navigator to allow remote users (e.g., trainees) to witness the surgical procedure in real-time as if they were present in the room.


Assuntos
Procedimentos Cirúrgicos Operatórios/educação , Telemedicina/métodos , Realidade Virtual , Humanos , Fatores de Tempo
5.
Stud Health Technol Inform ; 184: 161-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23400150

RESUMO

Surgical training plays an important role in assisting residents to develop critical skills. Providing effective surgical training, however, remains as a challenging task. Existing videotaped training instructions can only show imagery from a fixed viewpoint that lacks both depth perception and interactivity. We present a new portable immersive surgical training system that is capable of acquiring and displaying high fidelity 3D reconstructions of actual surgical procedures. Our solution utilizes a set of Microsoft Kinect sensors to simultaneously recover the participants, the surgical environment, and the surgical scene itself. We then develop a space-time navigator to allow the trainees to witness and explore a prior procedure as if they were there. Preliminary feedback from residents shows that our system is much more effective than conventional videotaped system.


Assuntos
Actigrafia/instrumentação , Biorretroalimentação Psicológica/instrumentação , Instrução por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Cirurgia Assistida por Computador/instrumentação , Transdutores , Interface Usuário-Computador , Colorimetria/instrumentação , Avaliação Educacional/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos
6.
Biodegradation ; 21(4): 513-23, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19960233

RESUMO

Methamidophos is one of the most widely used organophosphorus insecticides usually detectable in the environment. A facultative methylotroph, Hyphomicrobium sp. MAP-1, capable of high efficiently degrading methamidophos, was isolated from methamidophos-contaminated soil in China. It was found that the addition of methanol significantly promoted the growth of strain MAP-1 and enhanced its degradation of methamidophos. Further, this strain could utilize methamidophos as its sole carbon, nitrogen and phosphorus source for growth and could completely degrade 3,000 mg l(-1) methamidophos in 84 h under optimal conditions (pH 7.0, 30 degrees C). The enzyme responsible for methamidophos degradation was mainly located on the cell inner membrane (90.4%). During methamidophos degradation, three metabolites were detected and identified based on tandem mass spectrometry (MS/MS) and gas chromatography-mass spectrometry (GC-MS) analysis. Using this information, a biochemical degradation pathway of methamidophos by Hyphomicrobium sp. MAP-1 was proposed for the first time. Methamidophos is first cleaved at the P-N bond to form O,S-dimethyl hydrogen thiophosphate and NH(3). Subsequently, O,S-dimethyl hydrogen thiophosphate is hydrolyzed at the P-O bond to release -OCH(3) and form S-methyl dihydrogen thiophosphate. O,S-dimethyl hydrogen thiophosphate can also be hydrolyzed at the P-S bond to release -SCH(3) and form methyl dihydrogen phosphate. Finally, S-methyl dihydrogen thiophosphate and methyl dihydrogen phosphate are likely transformed into phosphoric acid.


Assuntos
Hyphomicrobium/metabolismo , Inseticidas/metabolismo , Compostos Organotiofosforados/metabolismo , Microbiologia do Solo , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , DNA Bacteriano/genética , DNA Ribossômico/genética , Hyphomicrobium/classificação , Hyphomicrobium/enzimologia , Hyphomicrobium/isolamento & purificação , Inseticidas/química , Dados de Sequência Molecular , Estrutura Molecular , Compostos Organotiofosforados/química , Filogenia , RNA Ribossômico 16S/genética
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