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1.
Biochem Biophys Res Commun ; 573: 9-12, 2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34375766

RESUMO

In recent years, the successful construction of tissues derived from established iPSCs has been disclosed, but it has been reported that the constructed tissues encounter problems of internal necrosis when their size increases. To solve this problem, a simulated microgravity device is used. However, the culture of early developing kidney cells using this device has not yet been reported. This study investigated whether developing kidney cells cultured in a simulated microgravity environment can differentiate into glomerular cells and renal epithelial cells. The results showed that both mouse developing kidney cells cultured in simulated microgravity and static environment formed kidney spheroids. In static culture, ureteric bud and glomerular structures were not found. While ureteric buds, podocytes, PECAM-1 positive cell aggregates, and primordial vascular plexus were formed in the kidney spheroids in simulated microgravity culture. Moreover, the expression level of the PECAM-1 gene was significant in simulated microgravity culture as compared to that of static culture. These results indicate that simulated microgravity is effective for the differentiation of developing kidney cells.


Assuntos
Técnicas de Cultura de Células , Rim/citologia , Simulação de Ausência de Peso , Animais , Diferenciação Celular , Células Cultivadas , Células Endoteliais/citologia , Células Epiteliais/citologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR
2.
Sensors (Basel) ; 20(11)2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32532007

RESUMO

The paper presents a novel hybrid network for large-scale action recognition from multiple modalities. The network is built upon the proposed weighted dynamic images. It effectively leverages the strengths of the emerging Convolutional Neural Network (CNN) and Recurrent Neural Network (RNN) based approaches to specifically address the challenges that occur in large-scale action recognition and are not fully dealt with by the state-of-the-art methods. Specifically, the proposed hybrid network consists of a CNN based component and an RNN based component. Features extracted by the two components are fused through canonical correlation analysis and then fed to a linear Support Vector Machine (SVM) for classification. The proposed network achieved state-of-the-art results on the ChaLearn LAP IsoGD, NTU RGB+D and Multi-modal & Multi-view & Interactive ( M 2 I ) datasets and outperformed existing methods by a large margin (over 10 percentage points in some cases).

3.
Int J Mol Sci ; 20(6)2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30909435

RESUMO

Renal disease is not rare among patients with inflammatory bowel disease (IBD) and is gaining interest as a target of research. However, related changes in glomerular structural have rarely been investigated. This study was aimed at clarifying the changes in collagens and glomerular filtration barrier (GFB)-related proteins of glomeruli in a dextran sulfate sodium (DSS)-induced colitis mouse model. Acute colitis was induced by administering 3.5% DSS in Slc:ICR strain mice for eight days. Histological changes to glomeruli were examined by periodic acid-Schiff (PAS) and Masson's trichrome staining. Expressions of glomerular collagens and GFB-related proteins were analyzed by immunofluorescent staining and Western blot analysis. DSS-colitis mice showed an elevated disease activity index (DAI), colon shortening, massive cellular infiltration and colon damage, confirming that DSS-colitis mice can be used as an IBD animal model. DSS-colitis mice showed increased glycoprotein and collagen deposition in glomeruli. Interestingly, we observed significant changes in glomerular collagens, including a decrease in type IV collagen, and an increment in type I and type V collagens. Moreover, declined GFB-related proteins expressions were detected, including synaptopodin, podocalyxin, nephrin and VE-cadherin. These results suggest that renal disease in DSS-colitis mice might be associated with changes in glomerular collagens and GFB-related proteins. These findings are important for further elucidation of the clinical pathological mechanisms underlying IBD-associated renal disease.


Assuntos
Colite/etiologia , Colite/metabolismo , Colágeno/metabolismo , Barreira de Filtração Glomerular/metabolismo , Glomérulos Renais/metabolismo , Animais , Biomarcadores , Biópsia , Colite/patologia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Progressão da Doença , Imuno-Histoquímica , Camundongos , Modelos Biológicos
4.
Nephrol Dial Transplant ; 29(6): 1168-77, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24319012

RESUMO

BACKGROUND: Antineutrophil cytoplasmic autoantibody (ANCA) directed against myeloperoxidase (MPO), a diagnostic criterion in MPO-ANCA-associated vasculitis (MPO-AAV), does not always correlate with disease activity. Here, we detected autoantibodies against moesin, which was located on the surface of stimulated endothelial cells, in the serum of patients. METHODS: The anti-moesin autoantibody titer was evaluated by ELISA. Seventeen kinds of cytokines/chemokines were measured by a Bio-Plex system. RESULTS: Serum creatinine in the anti-moesin autoantibody-positive group was higher than that in the negative group. Additionally, interferon (IFN)-γ, macrophage chemotactic peptide-1 (MCP-1), interleukin (IL)-2, IL-7, IL-12p70, IL-13, granulocyte/macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor were significantly higher in the positive group. Furthermore, IL-7 and IL-12p70 levels correlated with the anti-moesin autoantibody titer. Based on these findings and the binding of anti-moesin IgG to neutrophils and monocytes, we detected the secretion of cytokines/chemokines such as IFN-γ, MCP-1 and GM-CSF from these cells. CONCLUSIONS: The anti-moesin autoantibody existed in the serum of patients with MPO-AAV and was associated with the production of inflammatory cytokines/chemokines targeting neutrophils with a cytoplasmic profile, which suggests that the anti-moesin autoantibody has the possibility to be a novel autoantibody developing vasculitis via neutrophil and endothelial cell activation.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Autoanticorpos/sangue , Proteínas dos Microfilamentos/imunologia , Peroxidase/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiocinas/metabolismo , Endotélio Vascular/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Fator Estimulador de Colônias de Granulócitos/sangue , Humanos , Interleucinas/imunologia , Proteínas Inflamatórias de Macrófagos/sangue , Masculino , Pessoa de Meia-Idade
5.
Artigo em Inglês | MEDLINE | ID: mdl-38227417

RESUMO

Locating 3D objects from a single RGB image via Perspective-n-Point (PnP) is a long-standing problem in computer vision. Driven by end-to-end deep learning, recent studies suggest interpreting PnP as a differentiable layer, allowing for partial learning of 2D-3D point correspondences by backpropagating the gradients of pose loss. Yet, learning the entire correspondences from scratch is highly challenging, particularly for ambiguous pose solutions, where the globally optimal pose is theoretically non-differentiable w.r.t. the points. In this paper, we propose the EPro-PnP, a probabilistic PnP layer for general end-to-end pose estimation, which outputs a distribution of pose with differentiable probability density on the SE(3) manifold. The 2D-3D coordinates and corresponding weights are treated as intermediate variables learned by minimizing the KL divergence between the predicted and target pose distribution. The underlying principle generalizes previous approaches, and resembles the attention mechanism. EPro-PnP can enhance existing correspondence networks, closing the gap between PnP-based method and the task-specific leaders on the LineMOD 6DoF pose estimation benchmark. Furthermore, EPro-PnP helps to explore new possibilities of network design, as we demonstrate a novel deformable correspondence network with the state-of-the-art pose accuracy on the nuScenes 3D object detection benchmark. Our code is available at https://github.com/tjiiv-cprg/EPro-PnP-v2.

6.
Biochem Biophys Res Commun ; 441(3): 649-54, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24404584

RESUMO

Type V collagen (Col V) molecule, a minor component of kidney connective tissues, was found in adult cornea, and has been considered as a regulatory fibril-forming collagen that emerges into type I collagen to trigger the initiation of Col I fiber assembly. Col V was also found in injured, wound healing tissues or placenta, and was considered as a dysfunctional extracellular matrix (ECM). Reconstituted Col V fibril was characterized as an ECM to detach cells in vitro, and our previous study showed that the reconstituted Col V fibril facilitated the migration of glomerular endothelial cells and induced ECM remodeling, whereas Col V molecules stabilized cells. These facts suggest that not only the structure but also the function of Col V fibril are different from Col V molecule. Recently, Col V molecule has been reported existing in various developing tissues such as bone and lung, but Col V fibril has not been reported yet. In this study, we firstly explored the existence of Col V fibril in metanephroi, and found it distributed in the immature kidney tissues whereas disappeared when the tissues reached mature. It is likely that Col V fibril may form a prototype of pericellular microenvironment and the transient existence of Col V fibril may play a role as the pioneering ECM during metanephric tissue morphogenesis.


Assuntos
Colágeno Tipo V/metabolismo , Rim/embriologia , Rim/metabolismo , Animais , Microambiente Celular , Colágeno Tipo I/metabolismo , Matriz Extracelular , Feminino , Glomérulos Renais/embriologia , Glomérulos Renais/metabolismo , Camundongos , Camundongos Endogâmicos ICR
7.
Sensors (Basel) ; 13(1): 746-57, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23296331

RESUMO

In this paper, a novel direction of arrival (DOA) estimation algorithm called the Toeplitz fourth order cumulants multiple signal classification method (TFOC-MUSIC) algorithm is proposed through combining a fast MUSIC-like algorithm termed the modified fourth order cumulants MUSIC (MFOC-MUSIC) algorithm and Toeplitz approximation. In the proposed algorithm, the redundant information in the cumulants is removed. Besides, the computational complexity is reduced due to the decreased dimension of the fourth-order cumulants matrix, which is equal to the number of the virtual array elements. That is, the effective array aperture of a physical array remains unchanged. However, due to finite sampling snapshots, there exists an estimation error of the reduced-rank FOC matrix and thus the capacity of DOA estimation degrades. In order to improve the estimation performance, Toeplitz approximation is introduced to recover the Toeplitz structure of the reduced-dimension FOC matrix just like the ideal one which has the Toeplitz structure possessing optimal estimated results. The theoretical formulas of the proposed algorithm are derived, and the simulations results are presented. From the simulations, in comparison with the MFOC-MUSIC algorithm, it is concluded that the TFOC-MUSIC algorithm yields an excellent performance in both spatially-white noise and in spatially-color noise environments.

8.
IEEE Trans Pattern Anal Mach Intell ; 45(10): 11428-11442, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37163406

RESUMO

Motion recognition is a promising direction in computer vision, but the training of video classification models is much harder than images due to insufficient data and considerable parameters. To get around this, some works strive to explore multimodal cues from RGB-D data. Although improving motion recognition to some extent, these methods still face sub-optimal situations in the following aspects: (i) Data augmentation, i.e., the scale of the RGB-D datasets is still limited, and few efforts have been made to explore novel data augmentation strategies for videos; (ii) Optimization mechanism, i.e., the tightly space-time-entangled network structure brings more challenges to spatiotemporal information modeling; And (iii) cross-modal knowledge fusion, i.e., the high similarity between multimodal representations leads to insufficient late fusion. To alleviate these drawbacks, we propose to improve RGB-D-based motion recognition both from data and algorithm perspectives in this article. In more detail, firstly, we introduce a novel video data augmentation method dubbed ShuffleMix, which acts as a supplement to MixUp, to provide additional temporal regularization for motion recognition. Secondly, a Unified Multimodal De-coupling and multi-stage Re-coupling framework, termed UMDR, is proposed for video representation learning. Finally, a novel cross-modal Complement Feature Catcher (CFCer) is explored to mine potential commonalities features in multimodal information as the auxiliary fusion stream, to improve the late fusion results. The seamless combination of these novel designs forms a robust spatiotemporal representation and achieves better performance than state-of-the-art methods on four public motion datasets. Specifically, UMDR achieves unprecedented improvements of ↑ 4.5% on the Chalearn IsoGD dataset.

9.
Nephrol Dial Transplant ; 26(9): 2752-60, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21378392

RESUMO

BACKGROUND: Glomerular neutrophil infiltration has been thought to be a key pathological event in the development of myeloperoxidase (MPO)-specific anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis involving glomerulonephritis. Accordingly, we sought to explore the molecules responsible for glomerular neutrophil accumulation. METHODS: Glomerular neutrophil infiltration and renal chemokine expression in mice treated with anti-MPO IgG were evaluated. Chemokine expression in vitro induced by anti-MPO IgG was measured in the primary mouse glomerular endothelial cells (mGEC). The target molecule reacted with anti-MPO IgG on the mGEC was determined by peptide mass fingerprint analysis. RESULTS: A significant glomerular neutrophil infiltration was observed in the mice administered with anti-MPO IgG. The expressions of CXC chemokines, keratinocyte-derived chemokine (KC) and macrophage inflammatory protein-2 (MIP-2), were significantly increased in the renal cortex, indicating that these chemokines contribute to the neutrophil infiltration. Based on the previous findings of upregulation of adhesion molecule expression in mGEC treated with anti-MPO IgG, we examined whether mGEC secrete these chemokines in response to anti-MPO IgG. Indeed, anti-MPO IgG induced secretion of KC and MIP-2, leading to neutrophil chemotaxis in vitro. Furthermore, complete depletion of MPO in mGEC and serum using MPO-deficient mice showed an upregulation of intercellular adhesion molecule-1, indicating cross-reactive molecule(s) were existing on mGEC. We identified the molecule as moesin by a proteomic approach. CONCLUSIONS: The endothelial CXC chemokines, KC and MIP-2, contribute to infiltration of neutrophils in MPO-ANCA-associated vasculitis involving glomerulonephritis. The activation of glomerular endothelial cells by anti-MPO IgG appeared to directly involve a signaling through moesin.


Assuntos
Anticorpos Anti-Idiotípicos/sangue , Anticorpos Anti-Idiotípicos/imunologia , Células Endoteliais/metabolismo , Glomerulonefrite/metabolismo , Glomérulos Renais/metabolismo , Proteínas dos Microfilamentos/imunologia , Peroxidase/fisiologia , Animais , Western Blotting , Células Cultivadas , Quimiocina CXCL2/genética , Quimiocina CXCL2/metabolismo , Quimiocinas/genética , Quimiocinas/metabolismo , Eletroforese em Gel Bidimensional , Células Endoteliais/imunologia , Células Endoteliais/patologia , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Glomérulos Renais/imunologia , Glomérulos Renais/patologia , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
IEEE Trans Image Process ; 30: 5626-5640, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34125676

RESUMO

Gesture recognition has attracted considerable attention owing to its great potential in applications. Although the great progress has been made recently in multi-modal learning methods, existing methods still lack effective integration to fully explore synergies among spatio-temporal modalities effectively for gesture recognition. The problems are partially due to the fact that the existing manually designed network architectures have low efficiency in the joint learning of multi-modalities. In this paper, we propose the first neural architecture search (NAS)-based method for RGB-D gesture recognition. The proposed method includes two key components: 1) enhanced temporal representation via the proposed 3D Central Difference Convolution (3D-CDC) family, which is able to capture rich temporal context via aggregating temporal difference information; and 2) optimized backbones for multi-sampling-rate branches and lateral connections among varied modalities. The resultant multi-modal multi-rate network provides a new perspective to understand the relationship between RGB and depth modalities and their temporal dynamics. Comprehensive experiments are performed on three benchmark datasets (IsoGD, NvGesture, and EgoGesture), demonstrating the state-of-the-art performance in both single- and multi-modality settings. The code is available at https://github.com/ZitongYu/3DCDC-NAS.

11.
Yakugaku Zasshi ; 130(4): 565-74, 2010 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-20372002

RESUMO

The white of an egg, rendered opaque by boiling, can be converted into a thin, transparent and rigid material like glass by evaporating the moisture. This phenomenon is known as the vitrification of heat-denatured proteins. We applied vitrification technology to a collagen gel and converted it into a rigid glass-like material. We attempted to rehydrate the glass-like material and succeeded in preparing a novel stable state of collagen gel that was a thin and transparent membrane with excellent gel strength and protein permeability. We called it "collagen vitrigel" because it was produced from the vitrification process of a traditional hydrogel. Further, a framework-embedded collagen vitrigel membrane that can be easily turned inside out with tweezers was prepared by inserting a nylon membrane ring in the collagen sol prior to the gelation, thereby allowing the membrane to function as a removable cell culture substratum. Different types of anchorage-dependent cells could be cultured on both surfaces of the substratum by the manipulation of two-dimensional cultures, and consequently a three-dimensional crosstalk model with paracrine effects from each cell type was reconstructed. Also, the collagen vitrigel membrane containing a bioactive molecule provided a drug delivery system (DDS) with sustainable release. In this review, we summarize the recent progress of applied studies using the collagen vitrigel membrane as follows: a corneal model for eye irritant and permeability tests, a skin model for sensitization test, a renal glomerular model for evaluating blood filtration, an endometrial model for developing a new treatment and a DDS of hepatocyte growth factor for improving liver disorder.


Assuntos
Técnicas de Cultura de Células/métodos , Colágeno , Membranas Artificiais , Animais , Sistemas de Liberação de Medicamentos , Descoberta de Drogas , Géis , Temperatura Alta , Humanos , Modelos Biológicos , Comunicação Parácrina , Desnaturação Proteica
12.
Exp Cell Res ; 314(20): 3638-53, 2008 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-18845143

RESUMO

Although type V collagen (Col V) is present in developing and mature connective tissues of glomeruli, its primary function has not been elucidated yet. The purpose of this study was to elucidate the role of Col V fibrils in glomerular cells. We isolated primary cells from porcine kidney and cultured them on Col V fibrils reconstructed from purified Col V molecules extracted from porcine cornea. Time-lapse observation showed that Col V fibrils induce dynamic movement of glomerular endothelial cells (GEC) by stimulating them to extend long filopodial protrusions and wide lamellipodia. Col V signaling mediated through beta1 integrin activated phosphorylation of paxillin at tyrosine 118 (paxillin-pY118) and of focal adhesion kinase at tyrosine 861 (FAKpY861) at the cell periphery; a second Col V signal was mediated through neuroglycan 2 and activated FAKpY397. FAKpY861 was present in loose attachment points between Col V fibrils and GEC, allowing the cells to migrate easily. Activation of FAKpY397 induced incomplete focal adhesion at the centers of cells and caused cell movement. Therefore both signaling pathways facilitated cell motility, which was inhibited by the addition of antibodies to beta1 integrin, NG2, and Col V. We suggest that Col V fibrils activate 'outside-in' signaling in GEC and induce their dynamic motility.


Assuntos
Movimento Celular , Colágeno Tipo V/fisiologia , Células Endoteliais/fisiologia , Matriz Extracelular/fisiologia , Colágenos Fibrilares/fisiologia , Rim/citologia , Animais , Células Cultivadas , Colágeno Tipo V/metabolismo , Colágeno Tipo V/ultraestrutura , Matriz Extracelular/metabolismo , Matriz Extracelular/ultraestrutura , Colágenos Fibrilares/isolamento & purificação , Colágenos Fibrilares/metabolismo , Colágenos Fibrilares/ultraestrutura , Rim/metabolismo , Rim/fisiologia , Modelos Biológicos , Fosforilação , Proteínas Quinases/metabolismo , Receptores de Superfície Celular/fisiologia , Transdução de Sinais/fisiologia , Suínos
13.
Neural Netw ; 117: 163-178, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31170576

RESUMO

With the rapid development of multimedia technology, massive unlabelled data with high dimensionality need to be processed. As a means of dimensionality reduction, unsupervised feature selection has been widely recognized as an important and challenging pre-step for many machine learning and data mining tasks. Traditional unsupervised feature selection algorithms usually assume that the data instances are identically distributed and there is no dependency between them. However, the data instances are not only associated with high dimensional features but also inherently interconnected with each other. Furthermore, the inevitable noises mixed in data could degenerate the performances of previous methods which perform feature selection in original data space. Without label information, the connection information between data instances can be exploited and could help select relevant features. In this work, we propose a robust unsupervised feature selection method which embeds the latent representation learning into feature selection. Instead of measuring the feature importances in original data space, the feature selection is carried out in the learned latent representation space which is more robust to noises. The latent representation is modelled by non-negative matrix factorization of the affinity matrix which explicitly reflects the relationships of data instances. Meanwhile, the local manifold structure of original data space is preserved by a graph based manifold regularization term in the transformed feature space. An efficient alternating algorithm is developed to optimize the proposed model. Experimental results on eight benchmark datasets demonstrate the effectiveness of the proposed method.


Assuntos
Aprendizado de Máquina não Supervisionado , Mineração de Dados/métodos
15.
Biochem Biophys Rep ; 11: 72-78, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28955770

RESUMO

Addicsin (Arl6ip5) is a multifunctional physiological and pathophysiological regulator that exerts its effects by readily forming homo- and hetero-complexes with various functional factors. In particular, addicsin acts as a negative modulator of neural glutamate transporter excitatory amino acid carrier 1 (EAAC1) and participates in the regulation of intracellular glutathione (GSH) content by negatively modulating EAAC1-mediated cysteine and glutamate uptake. Addicsin is considered to play a crucial role in the onset of neurodegenerative diseases including epilepsy. However, the molecular dynamics of addicsin remains largely unknown. Here, we report the dynamics of addicsin in NG108-15 cells upon exposure to pentylenetetrazol (PTZ), a representative epileptogenic agent acting on the gamma-Aminobutyric acid A (GABAA) receptor. Fluorescent immunostaining analysis demonstrated that addicsin drastically changed its localization from the endoplasmic reticulum (ER) to the plasma membrane within 1 h of PTZ exposure in a dose-dependent manner. Moreover, addicsin was co-localized with the plasma membrane markers EAAC1 and Na+/K+ ATPase alpha-3 upon PTZ stimulation. This translocation was significantly inhibited by a non-competitive GABAA receptor antagonist, picrotoxin, but not by a competitive GABAA receptor antagonist, bicuculline. Furthermore, lactate dehydrogenase (LDH) assay and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay showed that PTZ-induced addicsin translocation was accompanied by a decrease of radical-scavenging activity and an increase of cytotoxicity in a PTZ dose-dependent manner. These findings suggest that PTZ induces the translocation of addicsin from the ER to the plasma membrane and modulates the redox system by regulating EAAC1-mediated GSH synthesis, which leads to the activation of cell death signaling.

16.
Regen Ther ; 4: 27-35, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31245485

RESUMO

Reconstruction of blood vessels is considered the most difficult part for the complicated organs, therefore, blood vessel construction is regarded as a key point for kidney regeneration in vitro. Vasculogenesis and angiogenesis are the two mechanisms to form blood vessels in embryonic organs, and most studies resided in vaculogenesis. Angiogenesis resided mostly in adult diseases such as wound healing, growth of tumors, and psoriasis diseases. However, renal angiogenesis is simply attributed to the sprouting of pre-existing blood vessel from dorsal aorta into metanephroi, and its occurrence is considered to be at a late stage of metanephric development. Since no techniques are available for delicate detection, the initial angiogenesis from dorsal aorta into metanephroi as well as its role in kidney development still remained unclear. In this study, we developed a method to detect the initial angiogenesis of dorsal aorta into metanephroi, and firstly clarified that dorsal aorta angiogenesis occurred at an early stage of metanephric development. We also elucidated the role of dorsal aorta angiogenesis in promoting the early blood vessel formation, tubule formation and glomeruli maturation. It is suggested that blood flow and dynamic circulation of various factors at the early developing stage may be prerequisite to a successful construction of blood vessels in the complicated organs either in vitro or in vivo. These findings contribute to a better understanding of dorsal aorta angiogenesis during kidney development and shed light on its significant value for the application of tissue engineering to complicated organs.

17.
Biomaterials ; 26(11): 1287-92, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15475058

RESUMO

We developed a novel selective cell-separation method based on using a poly(N-isopropylacrylamide)-graft-polypropylene (PNIPAAm-g-PP) membrane containing adsorbed monoclonal antibody specific to the target cell. This membrane was prepared by plasma-induced polymerization and soaking in an antibody solution at 37 degrees C. Poly(N-isopropylacrylamide) has a thermoresponsive phase transition: at 32 degrees C water-insoluble (hydrophobic) and water-soluble (hydrophilic) states interconvert. Adsorption of antibody onto PNIPAAm-g-PP membrane at 37 degrees C and its desorption at 4 degrees C was verified by fluorescence-microscopy of the PNIPAAm-g-PP membrane after soaking it in fluorescein-conjugated goat anti-mouse IgG in phosphate-buffered saline. PNIPAAm-g-PP membranes containing adsorbed anti-mouse CD80 monoclonal antibody preferentially captured mouse-CD80 transfected cells at 37 degrees C compared with membranes lacking antibody or containing anti-mouse CD86 monoclonal antibody. Detachment of captured cells from PNIPAAm-g-PP membranes was facilitated by washing at 4 degrees C because of the thermoresponsive phase transition of PNIPAAm. With this method, mouse CD80- or mouse CD86-transfected cells were enriched from a 1:1 cell suspension to 72% or 66%, simply and with high yield.


Assuntos
Resinas Acrílicas/química , Anticorpos/química , Adesão Celular/fisiologia , Separação Celular/métodos , Macrófagos/citologia , Macrófagos/fisiologia , Membranas Artificiais , Polipropilenos/química , Adsorção , Animais , Anticorpos/imunologia , Antígeno B7-1/imunologia , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Teste de Materiais , Camundongos , Ligação Proteica
18.
J Biosci Bioeng ; 99(6): 529-40, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16233828

RESUMO

The construction of renal glomerular tissue has provided an important tool not only for the understanding of renal physiology and pathology in blood ultrafiltration and cell dysfunction, but also in the application of tissue engineering to glomeruli regeneration and nephritic therapy. In this study, a novel method to reconstruct glomerular tissue combining cultured cells on a collagen vitrigel scaffold is described. The method consists of two newly developed techniques, one to isolate glomerular epithelial and mesangial cells rapidly from kidney, which facilitates the prolongation of cell population doublings and allows a long-term cell culture without losing cellular features, and another to prepare a stable and thin transparent collagen gel membrane termed collagen vitrigel that can facilitate three-dimensional cultures for reconstructing an epithelial-mesenchymal model. By combining the two methods, we cocultured glomerular epithelial and mesangial cells on both surfaces of the collagen vitrigel by the manipulation of two-dimensional cultures, resulting in the successful reconstruction of a three-dimensional glomerular organoid. The coculture results showed that the collagen vitrigel maintains cell growth and cell viability for more than 1 month, and surprisingly, the epithelial layer demonstrated polarity formation, which usually appears in in vivo normal epithelial cells existing at the glomerular basement membrane, but seldom appears in epithelial cells cultured in vitro. Moreover, the coculture results showed that fibronectin, an extracellular matrix component, and integrin beta1, a receptor of fibronectin, were detected in high amounts on both cells, suggesting our collagen vitrigel can provide a suitable environment for cell-cell interactions that stabilize the cell structure and may contribute to the polarity formation of epithelial cells.


Assuntos
Bioprótese , Colágeno/química , Regeneração Tecidual Guiada/métodos , Glomérulos Renais/citologia , Glomérulos Renais/fisiologia , Rins Artificiais , Engenharia Tecidual/métodos , Animais , Células Cultivadas , Humanos , Glomérulos Renais/cirurgia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Procedimentos de Cirurgia Plástica/métodos
19.
Nat Cell Biol ; 17(8): 984-93, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26192439

RESUMO

Successful pluripotent stem cell differentiation methods have been developed for several endoderm-derived cells, including hepatocytes, ß-cells and intestinal cells. However, stomach lineage commitment from pluripotent stem cells has remained a challenge, and only antrum specification has been demonstrated. We established a method for stomach differentiation from embryonic stem cells by inducing mesenchymal Barx1, an essential gene for in vivo stomach specification from gut endoderm. Barx1-inducing culture conditions generated stomach primordium-like spheroids, which differentiated into mature stomach tissue cells in both the corpus and antrum by three-dimensional culture. This embryonic stem cell-derived stomach tissue (e-ST) shared a similar gene expression profile with adult stomach, and secreted pepsinogen as well as gastric acid. Furthermore, TGFA overexpression in e-ST caused hypertrophic mucus and gastric anacidity, which mimicked Ménétrier disease in vitro. Thus, in vitro stomach tissue derived from pluripotent stem cells mimics in vivo development and can be used for stomach disease models.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias/fisiologia , Medicina Regenerativa/métodos , Estômago/fisiologia , Engenharia Tecidual/métodos , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Ácido Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Gastrite Hipertrófica/genética , Gastrite Hipertrófica/metabolismo , Gastrite Hipertrófica/patologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog/metabolismo , Histamina/farmacologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Organogênese , Pepsinogênio A/metabolismo , Fenótipo , Esferoides Celulares , Estômago/citologia , Estômago/efeitos dos fármacos , Fatores de Tempo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção , Fator de Crescimento Transformador alfa/genética , Fator de Crescimento Transformador alfa/metabolismo
20.
PLoS One ; 10(9): e0138192, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26376435

RESUMO

Embelin, a natural quinone found in the fruits of Embelia ribes, is commonly used in Ayurvedic home medicine for a variety of therapeutic potentials including anti-inflammation, anti-fever, anti-bacteria and anti-cancer. Molecular mechanisms of these activities and cellular targets have not been clarified to-date. We demonstrate that the embelin inhibits mortalin-p53 interactions, and activates p53 protein in tumor cells. We provide bioinformatics, molecular docking and experimental evidence to the binding affinity of embelin with mortalin and p53. Binding of embelin with mortalin/p53 abrogates their complex resulted in nuclear translocation and transcriptional activation function of p53 causing growth arrest in cancer cells. Furthermore, analyses of growth factors and metastatic signaling using antibody membrane array revealed their downregulation in embelin-treated cells. We also found that the embelin causes transcriptional attenuation of mortalin and several other proteins involved in metastatic signaling in cancer cells. Based on these molecular dynamics and experimental data, it is concluded that the anticancer activity of embelin involves targeting of mortalin, activation of p53 and inactivation of metastatic signaling.


Assuntos
Benzoquinonas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/metabolismo , Primulaceae/química , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Apoptose , Western Blotting , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Proteínas de Choque Térmico HSP70/genética , Humanos , Metástase Neoplásica , Análise Serial de Proteínas , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética
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