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1.
Zhongguo Zhong Yao Za Zhi ; 49(9): 2512-2521, 2024 May.
Artigo em Zh | MEDLINE | ID: mdl-38812155

RESUMO

The Shexiang Zhuifeng Zhitong Ointment with the effects of dispelling wind, removing dampness, dissipating cold, and relieving pain is used for treating arthralgia, muscular pain, and sprain pain caused by cold-dampness obstruction. To evaluate the efficacy and safety of Shexiang Zhuifeng Zhitong Ointment in relieving the pain due to knee osteoarthritis(syndrome of cold-dampness obstruction), a randomized, double-blind, parallel controlled, multicenter clinical trial was conducted. The stratified randomization method was used to randomize the 240 subjects into a treatment group and a control group in a ratio of 1∶1. In each group, 60 patients received external application for 12 h and the other 60 patients received external application for 6 h. The treatment group received external application of Shexiang Zhuifeng Zhitong Ointment, while the control group received external application of Shexiang Zhuifeng Ointment. The treatment lasted for 21 days in both groups. Follow-up was conducted on days 7, 14, and 21 of treatment. The results based on the full analysis set were as follows.(1)In visual analog scale(VAS) score, the mean difference in the VAS score between baseline and 12 h post-treatment was 3.02 in the treatment group and 2.31 in the control group, with a significant difference(P<0.05). The mean difference in the VAS score between baseline and 6 h post-treatment was 3.19 in the treatment group and 2.48 in the control group, with a significant difference(P<0.05).(2)Response rate in terms of VAS score, after treatment for 12 h, the response rate was 93.22% in the treatment group and 73.33% in the control group, with a significant difference(P<0.05). After treatment for 6 h, theresponse rate in the treatment group was 88.33%, which was higher than that(63.33%) in the control group(P<0.05).The results showed that Shexiang Zhuifeng Zhitong Ointment applied for 12 and 6 h effectively relieved the knee joint pain of patients with knee osteoarthritis due to cold-dampness obstruction, as demonstrated by the reduced VAS score, Western Ontario and McMaster Universities Arthritis Index(WOMAC), stiffness, and joint function score. Moreover, Shexiang Zhuifeng Zhitong Ointment outperformed the positive control Shexiang Zhuifeng Ointment in terms of reducing the VAS score, demonstrating a definitetherapeutic effect on the pain due to knee osteoarthritis(syndrome of cold-dampness obstruction).In addition, Shexiang Zhuifeng Zhitong Ointment did not cause other adverse reactions except for mild allergic reactions, which were common in the external application of traditional Chinese medicine plasters on the skin, inseveral patients.Neither other adverse reactions nor abnormalities of liver and kidney functions and electrocardiogram were observed. This ointment had high safety and could be popularized in clinical application.


Assuntos
Medicamentos de Ervas Chinesas , Pomadas , Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Masculino , Pessoa de Meia-Idade , Feminino , Método Duplo-Cego , Idoso , Resultado do Tratamento , Adulto , Dor/tratamento farmacológico , Dor/etiologia
2.
Int J Mol Sci ; 24(24)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38138967

RESUMO

In response to injury, vascular smooth muscle cells (VSMCs) of the arterial wall dedifferentiate into a proliferative and migratory phenotype, leading to intimal hyperplasia. The ERK1/2 pathway participates in cellular proliferation and migration, while dual-specificity phosphatase 6 (DUSP6, also named MKP3) can dephosphorylate activated ERK1/2. We showed that DUSP6 was expressed in low baseline levels in normal arteries; however, arterial injury significantly increased DUSP6 levels in the vessel wall. Compared with wild-type mice, Dusp6-deficient mice had smaller neointima. In vitro, IL-1ß induced DUSP6 expression and increased VSMC proliferation and migration. Lack of DUSP6 reduced IL-1ß-induced VSMC proliferation and migration. DUSP6 deficiency did not affect IL-1ß-stimulated ERK1/2 activation. Instead, ERK1/2 inhibitor U0126 prevented DUSP6 induction by IL-1ß, indicating that ERK1/2 functions upstream of DUSP6 to regulate DUSP6 expression in VSMCs rather than downstream as a DUSP6 substrate. IL-1ß decreased the levels of cell cycle inhibitor p27 and cell-cell adhesion molecule N-cadherin in VSMCs, whereas lack of DUSP6 maintained their high levels, revealing novel functions of DUSP6 in regulating these two molecules. Taken together, our results indicate that lack of DUSP6 attenuated neointima formation following arterial injury by reducing VSMC proliferation and migration, which were likely mediated via maintaining p27 and N-cadherin levels.


Assuntos
Fosfatases de Especificidade Dupla , Neointima , Lesões do Sistema Vascular , Animais , Camundongos , Caderinas , Movimento Celular , Proliferação de Células , Células Cultivadas , Fosfatases de Especificidade Dupla/genética , Hiperplasia , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso , Neointima/genética , Neointima/prevenção & controle , Lesões do Sistema Vascular/genética
3.
J Biomed Sci ; 29(1): 25, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35414069

RESUMO

BACKGROUND: Abdominal aortic aneurysm (AAA) is a relatively common and often fatal condition. A major histopathological hallmark of AAA is the severe degeneration of aortic media with loss of vascular smooth muscle cells (VSMCs), which are the main source of extracellular matrix (ECM) proteins. VSMCs and ECM homeostasis are essential in maintaining structural integrity of the aorta. Cysteine-rich protein 2 (CRP2) is a VSMC-expressed protein; however, the role of CRP2 in AAA formation is unclear. METHODS: To investigate the function of CRP2 in AAA formation, mice deficient in Apoe (Apoe-/-) or both CRP2 (gene name Csrp2) and Apoe (Csrp2-/-Apoe-/-) were subjected to an angiotensin II (Ang II) infusion model of AAA formation. Aortas were harvested at different time points and histological analysis was performed. Primary VSMCs were generated from Apoe-/- and Csrp2-/-Apoe-/- mouse aortas for in vitro mechanistic studies. RESULTS: Loss of CRP2 attenuated Ang II-induced AAA incidence and severity, accompanied by preserved smooth muscle α-actin expression and reduced elastin degradation, matrix metalloproteinase 2 (MMP2) activity, deposition of collagen, particularly collagen III (Col III), aortic tensile strength, and blood pressure. CRP2 deficiency decreased the baseline MMP2 and Col III expression in VSMCs and mitigated Ang II-induced increases of MMP2 and Col III via blunting Erk1/2 signaling. Rescue experiments were performed by reintroducing CRP2 into Csrp2-/-Apoe-/- VSMCs restored Ang II-induced Erk1/2 activation, MMP2 expression and activity, and Col III levels. CONCLUSIONS: Our results indicate that in response to Ang II stimulation, CRP2 deficiency maintains aortic VSMC density, ECM homeostasis, and structural integrity through Erk1/2-Col III and MMP2 axis and reduces AAA formation. Thus, targeting CRP2 provides a potential therapeutic strategy for AAA.


Assuntos
Angiotensina II , Aneurisma da Aorta Abdominal , Angiotensina II/efeitos adversos , Angiotensina II/metabolismo , Animais , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/genética , Apolipoproteínas E/metabolismo , Colágeno/efeitos adversos , Colágeno/metabolismo , Cisteína , Modelos Animais de Doenças , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo
4.
BMC Bioinformatics ; 22(Suppl 5): 94, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749635

RESUMO

BACKGROUND: Differentiating and counting various types of white blood cells (WBC) in bone marrow smears allows the detection of infection, anemia, and leukemia or analysis of a process of treatment. However, manually locating, identifying, and counting the different classes of WBC is time-consuming and fatiguing. Classification and counting accuracy depends on the capability and experience of operators. RESULTS: This paper uses a deep learning method to count cells in color bone marrow microscopic images automatically. The proposed method uses a Faster RCNN and a Feature Pyramid Network to construct a system that deals with various illumination levels and accounts for color components' stability. The dataset of The Second Affiliated Hospital of Zhejiang University is used to train and test. CONCLUSIONS: The experiments test the effectiveness of the proposed white blood cell classification system using a total of 609 white blood cell images with a resolution of 2560 × 1920. The highest overall correct recognition rate could reach 98.8% accuracy. The experimental results show that the proposed system is comparable to some state-of-art systems. A user interface allows pathologists to operate the system easily.


Assuntos
Aprendizado Profundo , Leucemia , Medula Óssea , Humanos , Processamento de Imagem Assistida por Computador , Leucócitos
5.
Eur Spine J ; 30(2): 576-584, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33180193

RESUMO

BACKGROUND: Posterior atlantoaxial fixation with screw rod forms an approximate "II" shape or "H" increasing transverse link for better stability. In order to improve stability and in consideration of difficult placement of transverse connecting rod, possibility of inadequate bone graft, some scholars have preliminarily researched biomechanics of a novel crossed rod as an approximate "X" configuration of screw rod. PURPOSE: The aim of this study was to evaluate and compare the biomechanics of the crossed and parallel rod configurations in the screw rod system for posterior atlantoaxial fixation on a cadaveric model. METHODS: Six fresh cervical specimens were used to complete the range of motion (ROM) testing by applying pure moments of ± 2.0 nm. Following intact state and under destabilization testing, screws were implanted. The specimens were then tested in the following sequence: Group BLS + PR (C2 bilateral laminar screws + parallel rod), Group BLS + CR (C2 bilateral laminar screws + crossed rod), LPRLS + PR (C2 left pedicle screw and right laminar screw + parallel rod), LPRLS + CR (C2 left pedicle screw and right laminar screw + crossed rod), BPS + PR (C2 bilateral pedicle screws + parallel rod) and BPS + CR (C2 bilateral pedicle screws + crossed rod). The ROM of the C1-2 segments was measured in flexion-extension, lateral bending and axial rotation. Six surgical constructs were compared between the groups and with intact condition, respectively. RESULTS: The six fixed modes significantly increased stability compared with both the intact and destabilization group in flexion-extension, lateral bending and axial rotation (p < .05). In extension, BPS + CR and BLS + CR showed greater stability than BLS + PR (p < .05). During flexion, the six fixation methods showed no statistical significance (p > .05). In left lateral bending, stability of the other five screw rod fixation techniques significantly increased when compared with BLS + PR (p < .05). In the right lateral bending direction, the stability of BLS + PR was worse than that of BPS + CR and BPS + PR (p < .05). In the left axial rotation, stability of BLS + CR, LPRLS + CR and BPS + CR was greater than that of BLS + PR, LPRLS + PR and BPS + PR (p < .05). In the right axial rotation, the stability of BPS + CR and BLS + CR was greater than that of BLS + PR (p < .05). CONCLUSION: The six investigated fixation methods provide sufficient biomechanical stability. The crossed rod configuration can further enhance the axial rotation stability of the screw rod system, which consists of C1 bilateral pedicle and C2 pedicle, or C2 lamina screws. The crossed rod can also improve the stability of the screw rod system made up of C1 bilateral pedicle and C2 lamina screws in lateral bending and extension. The crossed rod configuration is reliable and provides superior stability for clinical application.


Assuntos
Articulação Atlantoaxial , Fusão Vertebral , Articulação Atlantoaxial/cirurgia , Fenômenos Biomecânicos , Cadáver , Vértebras Cervicais , Humanos , Amplitude de Movimento Articular
6.
IEEE Trans Cybern ; 51(12): 5717-5727, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31944970

RESUMO

An imposing task for a reinforcement learning agent in an uncertain environment is to expeditiously learn a policy or a sequence of actions, with which it can achieve the desired goal. In this article, we present an incremental model learning scheme to reconstruct the model of a stochastic environment. In the proposed learning scheme, we introduce a clustering algorithm to assimilate the model information and estimate the probability for each state transition. In addition, utilizing the reconstructed model, we present an experience replay strategy to create virtual interactive experiences by incorporating a balance between exploration and exploitation, which greatly accelerates learning and enables planning. Furthermore, we extend the proposed learning scheme for a multiagent framework to decrease the effort required for exploration and to reduce the learning time in a large environment. In this multiagent framework, we introduce a knowledge-sharing algorithm to share the reconstructed model information among the different agents, as needed, and develop a computationally efficient knowledge fusing mechanism to fuse the knowledge acquired using the agents' own experience with the knowledge received from its teammates. Finally, the simulation results with comparative analysis are provided to demonstrate the efficacy of the proposed methods in the complex learning tasks.

7.
Polymers (Basel) ; 13(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198515

RESUMO

Photocurable polymers have become increasingly important for their quick prototyping and high accuracy when used in three dimensional (3D) printing. However, some of the common photocurable polymers are known to be brittle, cytotoxic and present low impact resistance, all of which limit their applications in medicine. In this study, thermal treatment was studied for its effect and potential applications on the mechanical properties, degradability and biocompatibility of glycerol-based photocurable polymers, poly(glycerol sebacate) acrylate (PGSA). In addition to the slight increase in elongation at break, a two-fold increase in both Young's modulus and ultimate tensile strength were also observed after thermal treatment for the production of thermally treated PGSA (tPGSA). Moreover, the degradation rate of tPGSA significantly decreased due to the increase in crosslinking density in thermal treatment. The significant increase in cell viability and metabolic activity on both flat films and 3D-printed scaffolds via digital light processing-additive manufacturing (DLP-AM) demonstrated high in vitro biocompatibility of tPGSA. The histological studies and immune staining indicated that tPGSA elicited minimum immune responses. In addition, while many scaffolds suffer from instability through sterilization processes, it was proven that once glycerol-based polymers have been treated thermally, the influence of autoclaving the scaffolds were minimized. Therefore, thermal treatment is considered an effective method for the overall enhancement and stabilization of photocurable glycerol-based polymeric scaffolds in medicine-related applications.

8.
Biofabrication ; 13(4)2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34233298

RESUMO

Development of transplantable engineered tissue has been hampered by lacking vascular network within the engineered tissue. Three-dimensional (3D) printing has emerged as a new technology with great potential in fabrication and customization of geometric microstructure. In this study, utilizing digital light processing system, we manufactured a recently designed novel 3D architecture scaffold with poly(glycerol sebacate) acrylate (PGSA). Vascular construct was subsequently generated by seeding stem cells within this scaffold. PGSA provided inductive substrate in terms of supporting three-germ layer differentiation of embryonic stem cells (ESCs) and also promoting ESCs-derived vascular progenitor cells (VPCs) differentiation into endothelial cells (ECs). Furthermore, the differentiation efficiency of VPCs into ECs on PGSA was much higher than that on collagen IV or fibronectin. The results from seeding VPCs in the rotating hexagonal PGSA scaffold suggest that this architectural framework is highly efficient for cell engraftment in 3D structures. After long-term suspension culture of the VPCs in scaffold under directed EC differentiation condition, VPC-differentiated ECs were populated in the scaffold and expressed EC markers. Transplantation of the vascular construct in mice resulted in formation of new vascular network and integration of the microvasculature within the scaffold into the existing vasculature of host tissue. Importantly, in a mouse model of wound healing, ECs from the transplanted vascular construct directly contributed to revascularization and enhanced blood perfusion at the injured site. Collectively, this transplantable vascular construct provides an innovative alternative therapeutic strategy for vascular tissue engineering.


Assuntos
Células Endoteliais , Células-Tronco , Animais , Diferenciação Celular , Camundongos , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais
9.
Comput Med Imaging Graph ; 84: 101763, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32805673

RESUMO

Conventional computer-aided detection systems (CADs) for colonoscopic images utilize shape, texture, or temporal information to detect polyps, so they have limited sensitivity and specificity. This study proposes a method to extract possible polyp features automatically using convolutional neural networks (CNNs). The objective of this work aims at building up a light-weight dual encoder-decoder model structure for polyp detection in colonoscopy Images. This proposed model, though with a relatively shallow structure, is expected to have the capability of a similar performance to the methods with much deeper structures. The proposed CAD model consists of two sequential encoder-decoder networks that consist of several CNN layers and full connection layers. The front end of the model is a hetero-associator (also known as hetero-encoder) that uses backpropagation learning to generate a set of reliably corrupted labeled images with a certain degree of similarity to a ground truth image, which eliminates the need for a large amount of training data that is usually required for medical images tasks. This dual CNN architecture generates a set of noisy images that are similar to the labeled data to train its counterpart, the auto-associator (also known as auto-encoder), in order to increase the successor's discriminative power in classification. The auto-encoder is also equipped with CNNs to simultaneously capture the features of the labeled images that contain noise. The proposed method uses features that are learned from open medical datasets and the dataset of Zhejiang University (ZJU), which contains around one thousand images. The performance of the proposed architecture is compared with a state-of-the-art detection model in terms of the metrics of the Jaccard index, the DICE similarity score, and two other geometric measures. The improvements in the performance of the proposed model are attributed to the effective reduction in false positives in the auto-encoder and the generation of noisy candidate images by the hetero-encoder.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Colonoscopia , Humanos , Sensibilidade e Especificidade
10.
Antioxidants (Basel) ; 9(11)2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33228202

RESUMO

Abdominal aortic aneurysm (AAA) and intracranial aneurysm (IA) are serious arterial diseases in the aorta and brain, respectively. AAA and IA are associated with old age in males and females, respectively, and if rupture occurs, they carry high morbidity and mortality. Aneurysmal subarachnoid hemorrhage (SAH) due to IA rupture has a high rate of complication and fatality. Despite these severe clinical outcomes, preventing or treating these devastating diseases remains an unmet medical need. Inflammation and oxidative stress are shared pathologies of these vascular diseases. Therefore, therapeutic strategies have focused on reducing inflammation and reactive oxygen species levels. Interestingly, in response to cellular stress, the inducible heme oxygenase-1 (HO-1) is highly upregulated and protects against tissue injury. HO-1 degrades the prooxidant heme and generates molecules with antioxidative and anti-inflammatory properties, resulting in decreased oxidative stress and inflammation. Therefore, increasing HO-1 activity is an attractive option for therapy. Several HO-1 inducers have been identified and tested in animal models for preventing or alleviating AAA, IA, and SAH. However, clinical trials have shown conflicting results. Further research and the development of highly selective HO-1 regulators may be needed to prevent the initiation and progression of AAA, IA, or SAH.

11.
Aging (Albany NY) ; 11(19): 8604-8622, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31596731

RESUMO

Cardiovascular diseases remain the leading cause of morbidity and mortality worldwide, particularly among older adults. Despite the advent of medical technology, restenosis is still an issue after interventional procedures. Tryptophan metabolite 5-methoxytryptophan (5-MTP) has recently been shown to protect against systemic inflammatory responses. This study aimed to investigate the function and mechanisms of 5-MTP in interventional procedure-induced restenosis. We found that after mouse femoral artery denudation with a guide wire, 5-MTP accelerated recovery of endothelium in the denuded area and reduced vascular leakage and intimal thickening. 5-MTP increased endothelial cell proliferation in the denuded arteries and rescued TNF-α-reduced endothelial cell proliferation and migration, likely via maintaining vascular endothelial growth factor receptor 2 activation. In contrast, 5-MTP preserved differentiated phenotype of medial vascular smooth muscle cells (VSMCs) and decreased VSMC proliferation and migration. Furthermore, 5-MTP maintained expression levels of critical transcription factors for VSMC marker gene expressions via attenuated activation of p38 MAPK and NFκB-p65. Our findings uncover a novel protective mechanism of 5-MTP in restenosis. In response to denudation injury, 5-MTP attenuates intimal hyperplasia via concerted but opposing actions on endothelial cells and VSMCs. Taken together, our results suggest that 5-MTP is a valuable therapeutic target for arterial injury-induced restenosis.


Assuntos
Reestenose Coronária , Endotélio Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Triptofano/análogos & derivados , Animais , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Reestenose Coronária/metabolismo , Reestenose Coronária/prevenção & controle , Camundongos , Fatores de Proteção , Triptofano/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
Redox Biol ; 15: 51-61, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29216542

RESUMO

Heme oxygenase (HO)-1 is an inducible stress response protein and well known to protect cells and tissues against injury. Despite its important function in cytoprotection against physiological stress, the role of HO-1 in embryonic stem cell (ESC) differentiation remains largely unknown. We showed previously that induced pluripotent stem (iPS) cells that lack HO-1 are more sensitive to oxidant stress-induced cell death and more prone to lose pluripotent markers upon LIF withdrawal. To elucidate the role of HO-1 in ESC differentiation and to rule out the controversy of potential gene flaws in iPS cells, we derived and established mouse HO-1 knockout ESC lines from HO-1 knockout blastocysts. Using wild type D3 and HO-1 knockout ESCs in the 3-dimensional embryoid body (EB) differentiation model, we showed that at an early time point during EB development, an absence of HO-1 led to enhanced ROS level, concomitant with increased expressions of master mesodermal regulator brachyury and endodermal marker GATA6. In addition, critical smooth muscle cell (SMC) transcription factor serum response factor and its coactivator myocardin were enhanced. Furthermore, HO-1 deficiency increased Smad2 in ESCs and EBs, revealing a role of HO-1 in controlling Smad2 level. Smad2 not only mediates mesendoderm differentiation of mouse ESCs but also SMC development. Collectively, loss of HO-1 resulted in higher level of mesodermal and SMC regulators, leading to accelerated and enhanced SMC marker SM α-actin expression. Our results reveal a previously unrecognized function of HO-1 in regulating SMC gene expressions during ESC-EB development. More importantly, our findings may provide a novel strategy in enhancing ESC differentiation toward SMC lineage.


Assuntos
Desenvolvimento Embrionário/genética , Heme Oxigenase-1/genética , Células-Tronco Embrionárias Murinas/metabolismo , Animais , Blastocisto/metabolismo , Diferenciação Celular/genética , Corpos Embrioides/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Camundongos , Camundongos Knockout , Miócitos de Músculo Liso/metabolismo
13.
IEEE Trans Cybern ; 45(5): 964-76, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25122850

RESUMO

In a multiagent system, if agents' experiences could be accessible and assessed between peers for environmental modeling, they can alleviate the burden of exploration for unvisited states or unseen situations so as to accelerate the learning process. Since how to build up an effective and accurate model within a limited time is an important issue, especially for complex environments, this paper introduces a model-based reinforcement learning method based on a tree structure to achieve efficient modeling and less memory consumption. The proposed algorithm tailored a Dyna-Q architecture to multiagent systems by means of a tree structure for modeling. The tree-model built from real experiences is used to generate virtual experiences such that the elapsed time in learning could be reduced. As well, this model is suitable for knowledge sharing. This paper is inspired by the concept of knowledge sharing methods in multiagent systems where an agent could construct a global model from scattered local models held by individual agents. Consequently, it can increase modeling accuracy so as to provide valid simulated experiences for indirect learning at the early stage of learning. To simplify the sharing process, the proposed method applies resampling techniques to grafting partial branches of trees containing required and useful experiences disseminated from experienced peers, instead of merging the whole trees. The simulation results demonstrate that the proposed sharing method can achieve the objectives of sample efficiency and learning acceleration in multiagent cooperation applications.

14.
Biomaterials ; 35(11): 3607-17, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24462361

RESUMO

Liver transplantation is the ultimate treatment for severe hepatic failure to date. However, the limited supply of donor organs has severely hampered this treatment. So far, great potentials of using mesenchymal stem cells (MSCs) to replenish the hepatic cell population have been shown; nevertheless, there still is a lack of an optimal three-dimensional scaffold for generation of well-transplantable hepatic tissues. In this study, we utilized a cryo-chemical decellularization method which combines physical and chemical approach to generate acellular liver scaffolds (ALS) from the whole liver. The produced ALS provides a biomimetic three-dimensional environment to support hepatic differentiation of MSCs, evidenced by expression of hepatic-associated genes and marker protein, glycogen storage, albumin secretion, and urea production. It is also found that hepatic differentiation of MSCs within the ALS is much more efficient than two-dimensional culture in vitro. Importantly, the hepatic-like tissues (HLT) generated by repopulating ALS with MSCs are able to act as functional grafts and rescue lethal hepatic failure after transplantation in vivo. In summary, the cryo-chemical method used in this study is suitable for decellularization of liver and create acellular scaffolds that can support hepatic differentiation of MSCs and be used to fabricate functional tissue-engineered liver constructs.


Assuntos
Temperatura Baixa , Fígado/patologia , Células-Tronco Mesenquimais/citologia , Engenharia Tecidual/métodos , Animais , Biomarcadores/metabolismo , Diferenciação Celular/genética , Regulação da Expressão Gênica , Fígado/metabolismo , Fígado/fisiopatologia , Fígado/ultraestrutura , Transplante de Fígado , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Reação em Cadeia da Polimerase em Tempo Real , Alicerces Teciduais
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