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1.
Mol Neurobiol ; 61(3): 1687-1703, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37755583

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation under investigation for treatment of a wide range of neurological disorders. In particular, the therapeutic application of rTMS for neurodegenerative diseases such as Alzheimer's disease (AD) is attracting attention. However, the mechanisms underlying the therapeutic efficacy of rTMS have not yet been elucidated, and few studies have systematically analyzed the stimulation parameters. In this study, we found that treatment with rTMS contributed to restoration of memory deficits by activating genes involved in synaptic plasticity and long-term memory. We evaluated changes in several intracellular signaling pathways in response to rTMS stimulation; rTMS treatment activated STAT, MAPK, Akt/p70S6K, and CREB signaling. We also systematically investigated the influence of rTMS parameters. We found an effective range of applications for rTMS and determined the optimal combination to achieve the highest efficiency. Moreover, application of rTMS inhibited the increase in cell death induced by hydrogen peroxide. These results suggest that rTMS treatment exerts a neuroprotective effect on cellular damage induced by oxidative stress, which plays an important role in the pathogenesis of neurological disorders. rTMS treatment attenuated streptozotocin (STZ)-mediated cell death and AD-like pathology in neuronal cells. In an animal model of sporadic AD caused by intracerebroventricular STZ injection, rTMS application improved cognitive decline and showed neuroprotective effects on hippocampal histology. Overall, this study will help in the design of stimulation protocols for rTMS application and presents a novel mechanism that may explain the therapeutic effects of rTMS in neurodegenerative diseases, including AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Animais , Estimulação Magnética Transcraniana/métodos , Doença de Alzheimer/metabolismo , Estreptozocina , Hipocampo/metabolismo
2.
BMC Cancer ; 22(1): 852, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927628

RESUMO

Tumor acidosis, a common phenomenon in solid cancers such as breast cancer, is caused by the abnormal metabolism of cancer cells. The low pH affects cells surrounding the cancer, and tumor acidosis has been shown to inhibit the activity of immune cells. Despite many previous studies, the immune surveillance mechanisms are not fully understood. We found that the expression of PD-L1 was significantly increased under conditions of extracellular acidosis in MDA-MB-231 cells. We also confirmed that the increased expression of PD-L1 mediated by extracellular acidosis was decreased when the pH was raised to the normal range. Gene set enrichment analysis (GSEA) of public breast cancer patient databases showed that PD-L1 expression was also highly correlated with IL-6/JAK/STAT3 signaling. Surprisingly, the expression of both phospho-tyrosine STAT3 and PD-L1 was significantly increased under conditions of extracellular acidosis, and inhibition of STAT3 did not increase the expression of PD-L1 even under acidic conditions in MDA-MB-231 cells. Based on these results, we suggest that the expression of PD-L1 is increased by tumor acidosis via activation of STAT3 in MDA-MB-231 cells.


Assuntos
Antígeno B7-H1 , Neoplasias da Mama , Antígeno B7-H1/metabolismo , Mama/patologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Microambiente Tumoral
3.
Int J Mol Sci ; 23(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35887140

RESUMO

Previous studies have shown that early therapeutic events of neural precursor cells (NPCs) transplantation to animals with acute ischemic stroke readily protected neuronal cell damage and improved behavioral recovery through paracrine mechanisms. In this study, we tested the hypothesis that administration of conditioned medium from NPCs (NPC-CMs) could recapitulate the beneficial effects of cell transplantation. Rats with permanent middle cerebral artery occlusion (pMCAO) were randomly assigned to one of the following groups: PBS control, Vehicle (medium) controls, single (NPC-CM(S)) or multiple injections of NPC-CM(NPC-CM(M)) groups. A single intravenous injection of NPC-CM exhibited strong neuroregenerative potential to induce behavioral recovery, and multiple injections enhanced this activity further by suppressing inflammatory damage and inducing endogenous neurogenesis leading to histopathological and functional recovery. Proteome analysis of NPC-CM identified a number of proteins that are known to be associated with nervous system development, neurogenesis, and angiogenesis. In addition, transcriptome analysis revealed the importance of the inflammatory response during stroke recovery and some of the key hub genes in the interaction network were validated. Thus, our findings demonstrated that NPC-CM promoted functional recovery and reduced cerebral infarct and inflammation with enhanced endogenous neurogenesis, and the results highlighted the potency of NPC-CM in stroke therapy.


Assuntos
AVC Isquêmico , Células-Tronco Neurais , Células-Tronco Pluripotentes , Acidente Vascular Cerebral , Animais , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Humanos , Neurogênese , Neurônios , Células-Tronco Pluripotentes/patologia , Ratos , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/terapia
4.
J Toxicol Environ Health A ; 85(4): 163-174, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-34763616

RESUMO

Bisphenol F (BPF) is classified as a harmful substance by the U.S. Environmental Protection Agency. Although previous studies focused on human exposure to BPF via direct consumption or inhalation, few investigators assessed potential toxicological effects following skin contact. The aim of this study was to examine (1) the degree and pattern by which BPF is absorbed onto the skin in vivo, and (2) determination of toxicity and safety using the following tests: acute dermal; a 28-day repeat dermal; a skin irritation; an eye irritation; and a skin sensitization. As indicated by the amount of BPF remaining in the epidermis or dermis, data demonstrated that BPF was absorbed through the skin at a 26.5% rate. BPF penetrated the subcutaneous layer at a "fast rate" (Kp: 2.2E-02). Although no toxicological changes or local irritation were observed following skin exposure, BPF induced potent sensitization. In summary, the findings of this study showed that BPF penetrated and was absorbed into the skin at a high rate which was associated with enhanced chemical-induced skin sensitization and this may have significant implications following exposure of skin to BPF.


Assuntos
Compostos Benzidrílicos/toxicidade , Olho/efeitos dos fármacos , Fenóis/toxicidade , Pele/efeitos dos fármacos , Animais , Feminino , Humanos , Masculino , Coelhos , Ratos Sprague-Dawley , Absorção Cutânea , Testes de Toxicidade Aguda
5.
Med Biol Eng Comput ; 57(12): 2693-2703, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31650342

RESUMO

Center of pressure (COP) trajectories of human can maintain regulation of forward progression and stability of lateral sway during walking. The insole pressure system can only detect COP trajectories of each foot during single stance. In this study, we developed artificial neural network models that could present COP trajectories in an integrated coordinate system during a complete gait cycle using pressure information of the insole system. A feed forward artificial neural network (FFANN) and a long short-term memory (LSTM) model were developed. For FFANN, among 198 pressure sensors from Pedar-X insoles, proper input variables were selected using sequential forward selection to reduce input dimension. The LSTM model used all 198 signals as inputs because of its self-learning characteristic. As results of cross-validation, the FFANN model showed correlation coefficients of 0.98-0.99 and 0.93-0.95 in anterior/posterior and medial/lateral directions, respectively. For the LSTM model, correlation coefficients were similar to those of FFANN. However, the relative root mean square error (12.5%) of the FFANN model was higher than that (9.8%) of the LSTM model in medial/lateral direction (p = 0.03). This study can be used for quantitative evaluation of clinical diagnosis and rehabilitation status for patient with various diseases through further training using varied databases. Graphical abstract Architectures of neural networks developed in this study (a feed forward artificial neural network; b LSTM network).


Assuntos
Marcha/fisiologia , Adulto , Fenômenos Biomecânicos/fisiologia , Bases de Dados Factuais , Pé/fisiologia , Humanos , Aprendizado de Máquina , Masculino , Redes Neurais de Computação , Sapatos , Caminhada/fisiologia , Adulto Jovem
6.
Technol Health Care ; 26(S1): 291-306, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29710757

RESUMO

This study was conducted according to the method presented in the Republic of Korea Pharmacopoeia 11th Revision, aseptic test method to evaluate the suitability of sterilization for a sterile needle (4 Pin Multi-needle). In this study, four tests were conducted: sterility test, cytotoxicity test, acute toxicity test, skin sensitization test. First, in the aseptic test, the microorganism was not proliferated in the aseptic test of the medium. As a result of the performance test of the medium, it was confirmed that the microorganism developed within 3 days and the fungus was evident within 5 days. Based on this, it was confirmed that the medium was suitable, and as a result of the aseptic test, the development of microorganisms was not observed during the total culture period. Based on these results, tests were conducted which were confirmed to be suitable for aseptic testing because the development of bacteria on the provided samples was not recognized. For cytotoxicity tests ISO10993-5; 2009 (Biological Evaluation of Medical Devices, Part 5: Test for in vitro Cytotoxicity). As a result, the MEM eluate of the test substance caused very slight cytotoxicity to the fibroblasts of the mouse and was judged to be Grade 1 (Slightly cytotoxic) according to the judgment standard of ISO 10993-5. On the other hand, solvent control, negative control and positive control showed the expected results on the test. Acute Toxicity Test Results: It was judged that there was no systemic toxicity change when ICR mice were treated with 50 mL/kg B.W. of the eluate of sterile injectable needle for 72 hours. Skin sensitization test result: The Hartley guinea pig was evaluated as a substance which is evaluated as a substance which does not induce any skin reaction when skin sensitization is applied to the dissected material of the sterile injectable needle and is weak in skin sensitivity. Based on the above tests, we will study the stability and efficacy of more reliable medical devices based on the verification and performance of medical devices.


Assuntos
Mesoterapia/métodos , Agulhas/microbiologia , Esterilização/métodos , Animais , Dermatite Alérgica de Contato/microbiologia , Fibroblastos/microbiologia , Cobaias , Camundongos , Reprodutibilidade dos Testes , República da Coreia , Testes Cutâneos , Esterilização/normas , Testes de Toxicidade
7.
Technol Health Care ; 24 Suppl 2: S569-75, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27163319

RESUMO

An abdominal aortic aneurysm doesn't result in specific symptoms, and so providing a successful diagnosis can be challenging. Patients may require surgery for successful treatment, with the risk of aortic rupture being dependent on diameter. In this study, a CT screen of a patient with an aneurysm of the abdominal aorta was processed. In order to provide a more accurate and comfortable diagnosis, and to more easily determine the diameter of the abdominal aortic aneurysm, the Sobel and Top-hat methods were employed. Using a filtered screen overlap for the CT scan, the aortic diameter of a patient could be compared with the diameter of a healthy individual, thus allowing an immediate and accurate comparison. It was found that with a diameter of more than 40 mm the risk of rupture is higher.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/patologia , Ruptura Aórtica , Humanos , Medição de Risco , Tomografia Computadorizada por Raios X/métodos
8.
Biomed Mater Eng ; 26 Suppl 1: S1193-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26405878

RESUMO

In this study, the radiation generated in the diagnosis of scoliosis, to solve the problems by using an infrared camera and an optical marker system that can diagnose scoliosis developed. System developed by the infrared camera attached to the optical spinal curvature is recognized as a marker to shoot the angle between the two optical markers are measured. Measurement of angle, we used the Cobb's Angle method used in the diagnosis of spinal scoliosis. We developed a software to be able to output to the screen using an infrared camera to diagnose spinal scoliosis. Software is composed of camera output unit was manufactured in Labview, angle measurement unit, in Cobb's Angle measurement unit. In the future, kyphosis, Hallux Valgus, such as the diagnosis of orthopedic disorders that require the use of a diagnostic system is expected case.


Assuntos
Pontos de Referência Anatômicos/patologia , Marcadores Fiduciais , Interpretação de Imagem Assistida por Computador/métodos , Fotografação/instrumentação , Fotografação/métodos , Escoliose/patologia , Adolescente , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Imageamento Tridimensional/métodos , Raios Infravermelhos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Biochem Biophys Res Commun ; 463(4): 1122-8, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26079886

RESUMO

Camptothecin is an anti-cancer drug extracted from Camptotheca acuminata, a tree native to mainland China. Phase III clinical trials for camptothecin have been completed, and it is now used as a chemotherapeutic reagent. We identified a novel function of camptothecin that affects adipocyte differentiation. Following treatment with camptothecin, endogenous or overexpressed PPARγ becomes destabilized; this was prevented in the presence of MG132, a proteasome inhibitor. Our findings suggest that camptothecin is able to induce proteasome-dependent degradation of PPARγ. The ubiquitylation of PPARγ increased in the presence of camptothecin. Adipogenic differentiation of 3T3-L1 cells was prevented by campothecin and topotecan, but not by irinotecan, confirming our initial findings. Our results suggest a possible role for camptothecin analogs in the regulation of PPARγ.


Assuntos
Adipócitos/efeitos dos fármacos , Camptotecina/farmacologia , Diferenciação Celular/efeitos dos fármacos , PPAR gama/metabolismo , Inibidores da Topoisomerase I/farmacologia , Topotecan/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Proteólise
11.
Anal Chem ; 85(3): 1468-74, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23276151

RESUMO

Analysis of protein dynamics using single-molecule fluorescence resonance energy transfer (smFRET) is widely used to understand the structure and function of proteins. Nonetheless, site-specific labeling of proteins with a pair of donor and acceptor dyes still remains a challenge. Here we present a general and facile method for site-specific dual labeling of proteins by incorporating two different, readily available, unnatural amino acids (p-acetylphenylalanine and alkynyllysine) for smFRET. We used newly evolved alkynyllysine-specific aminoacyl-tRNA synthetase/tRNA(UCA) and p-acetylphenylalanyl-tRNA synthetase/tRNA(CUA). The utility of our approach was demonstrated by analyzing the conformational change of dual-labeled calmodulin using smFRET measurements. The present labeling approach is devoid of major limitations in conventional cysteine-based labeling. Therefore, our method will significantly increase the repertoire of proteins available for FRET study and expand our ability to explore more complicated molecular dynamics.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Proteínas/metabolismo , RNA de Transferência/metabolismo , Sequência de Bases , Sítios de Ligação/fisiologia , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Proteínas/química , Proteínas/genética , RNA de Transferência/química , RNA de Transferência/genética
12.
BMB Rep ; 45(9): 496-508, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23010170

RESUMO

Fas-associated protein with death domain (FADD), an adaptor that bridges death receptor signaling to the caspase cascade, is indispensible for the induction of extrinsic apoptotic cell death. Interest in the non-apoptotic function of FADD has greatly increased due to evidence that FADD-deficient mice or dominant-negative FADD transgenic mice result in embryonic lethality and an immune defect without showing apoptotic features. Numerous studies have suggested that FADD regulates cell cycle progression, proliferation, and autophagy, affecting these phenomena. Recently, programmed necrosis, also called necroptosis, was shown to be a key mechanism that induces embryonic lethality and an immune defect. Supporting these findings, FADD was shown to be involved in various necroptosis models. In this review, we summarize the mechanism of extrinsic apoptosis and necroptosis, and discuss the in vivo and in vitro roles of FADD in necroptosis induced by various stimuli.


Assuntos
Apoptose/imunologia , Proteína de Domínio de Morte Associada a Fas/metabolismo , Necrose , Animais , Caspase 8/metabolismo , Receptores de Morte Celular/metabolismo , Transdução de Sinais/imunologia , Receptores Toll-Like/metabolismo , Fatores de Necrose Tumoral/metabolismo
13.
FEBS Lett ; 586(6): 729-33, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22289181

RESUMO

Posttranslational modifications play a crucial role in modulating protein structure and function. Genetic incorporation of unnatural amino acids into a specific site of a protein facilitates the systematic study of protein modifications including acetylation. We here report the directed evolution of pyrrolysyl-tRNA synthetase (PylRS) from Methanosarcina mazei to create N-acetyl lysyl-tRNA synthetases (AcKRSs) using a new selection system based on the killing activity of the toxic ccdB gene product. The amino acid specificity of these and of published AckRSs was tested in vitro and in vivo, and the enzyme-kinetic properties of the AckRSs were evaluated for the first time.


Assuntos
Proteínas de Bactérias/metabolismo , Evolução Molecular Direcionada , Lisina-tRNA Ligase/metabolismo , Lisina/metabolismo , Aminoacil-RNA de Transferência/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Lisina/química , Lisina-tRNA Ligase/química , Lisina-tRNA Ligase/genética , Methanosarcina/genética , Methanosarcina/metabolismo , Processamento de Proteína Pós-Traducional , Aminoacil-RNA de Transferência/química , Aminoacil-RNA de Transferência/genética , Especificidade por Substrato
14.
BMB Rep ; 42(5): 299-303, 2009 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-19470245

RESUMO

In this study, we use promoter analysis to show that interaction between Jab1 and p53 induces suppression of p53 activation in U2OS and H1299 cells. Interaction between p53 and Jab1 was further confirmed by immunoprecipitation and immunofluorescent analyses. In particular, Jab1 was able to induce nuclear export of p53 as previously reported. When Jab1 was overexpressed in U2OS cells followed by etoposide or hydrogen peroxide (H(2)O(2)), cell death induced by such stresses was protected against. On the contrary, when the level of Jab1 was suppressed in U2OS cells, cytotoxicity imposed by etoposide and H(2)O(2) was dramatically increased, suggesting a cell protective role for Jab1. These results indicate that Jab1 is a negative regulator of p53 and a plausible oncogene.


Assuntos
Dano ao DNA , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeo Hidrolases/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Antineoplásicos Fitogênicos/metabolismo , Complexo do Signalossomo COP9 , Morte Celular/fisiologia , Linhagem Celular Tumoral , Etoposídeo/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Oxidantes/metabolismo , Peptídeo Hidrolases/genética , Ligação Proteica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteína Supressora de Tumor p53/genética
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