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1.
Sensors (Basel) ; 18(2)2018 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-29364188

RESUMEN

Indoor occupants' positions are significant for smart home service systems, which usually consist of robot service(s), appliance control and other intelligent applications. In this paper, an innovative localization method is proposed for tracking humans' position in indoor environments based on passive infrared (PIR) sensors using an accessibility map and an A-star algorithm, aiming at providing intelligent services. First the accessibility map reflecting the visiting habits of the occupants is established through the integral training with indoor environments and other prior knowledge. Then the PIR sensors, which placement depends on the training results in the accessibility map, get the rough location information. For more precise positioning, the A-start algorithm is used to refine the localization, fused with the accessibility map and the PIR sensor data. Experiments were conducted in a mock apartment testbed. The ground truth data was obtained from an Opti-track system. The results demonstrate that the proposed method is able to track persons in a smart home environment and provide a solution for home robot localization.

2.
Sensors (Basel) ; 18(5)2018 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-29757211

RESUMEN

Recent research has shown that the ubiquitous use of cameras and voice monitoring equipment in a home environment can raise privacy concerns and affect human mental health. This can be a major obstacle to the deployment of smart home systems for elderly or disabled care. This study uses a social robot to detect embarrassing situations. Firstly, we designed an improved neural network structure based on the You Only Look Once (YOLO) model to obtain feature information. By focusing on reducing area redundancy and computation time, we proposed a bounding-box merging algorithm based on region proposal networks (B-RPN), to merge the areas that have similar features and determine the borders of the bounding box. Thereafter, we designed a feature extraction algorithm based on our improved YOLO and B-RPN, called F-YOLO, for our training datasets, and then proposed a real-time object detection algorithm based on F-YOLO (RODA-FY). We implemented RODA-FY and compared models on our MAT social robot. Secondly, we considered six types of situations in smart homes, and developed training and validation datasets, containing 2580 and 360 images, respectively. Meanwhile, we designed three types of experiments with four types of test datasets composed of 960 sample images. Thirdly, we analyzed how a different number of training iterations affects our prediction estimation, and then we explored the relationship between recognition accuracy and learning rates. Our results show that our proposed privacy detection system can recognize designed situations in the smart home with an acceptable recognition accuracy of 94.48%. Finally, we compared the results among RODA-FY, Inception V3, and YOLO, which indicate that our proposed RODA-FY outperforms the other comparison models in recognition accuracy.

3.
Int J Mol Sci ; 15(5): 7049-63, 2014 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-24776757

RESUMEN

Polyethylenimine (PEI) has attracted much attention as a DNA condenser, but its toxicity and non-specific targeting limit its potential. To overcome these limitations, Antheraea pernyi silk fibroin (ASF), a natural protein rich in arginyl-glycyl-aspartic acid (RGD) peptides that contains negative surface charges in a neutral aqueous solution, was used to coat PEI/DNA complexes to form ASF/PEI/DNA ternary complexes. Coating these complexes with ASF caused fewer surface charges and greater size compared with the PEI/DNA complexes alone. In vitro transfection studies revealed that incorporation of ASF led to greater transfection efficiencies in both HEK (human embryonic kidney) 293 and HCT (human colorectal carcinoma) 116 cells, albeit with less electrostatic binding affinity for the cells. Moreover, the transfection efficiency in the HCT 116 cells was higher than that in the HEK 293 cells under the same conditions, which may be due to the target bonding affinity of the RGD peptides in ASF for integrins on the HCT 116 cell surface. This result indicated that the RGD binding affinity in ASF for integrins can enhance the specific targeting affinity to compensate for the reduction in electrostatic binding between ASF-coated PEI carriers and cells. Cell viability measurements showed higher cell viability after transfection of ASF/PEI/DNA ternary complexes than after transfection of PEI/DNA binary complexes alone. Lactate dehydrogenase (LDH) release studies further confirmed the improvement in the targeting effect of ASF/PEI/DNA ternary complexes to cells. These results suggest that ASF-coated PEI is a preferred transfection reagent and useful for improving both the transfection efficiency and cell viability of PEI-based nonviral vectors.


Asunto(s)
ADN/administración & dosificación , Fibroínas/química , Células HCT116/metabolismo , Células HEK293/metabolismo , Mariposas Nocturnas/química , Polietileneimina/química , Transfección , Animales , ADN/genética , Fibroínas/metabolismo , Humanos , Oligopéptidos/química , Oligopéptidos/metabolismo , Polietileneimina/metabolismo
4.
IEEE Trans Vis Comput Graph ; 28(7): 2668-2681, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-33170778

RESUMEN

We present a new framework for online dense 3D reconstruction of indoor scenes by using only depth sequences. This research is particularly useful in cases with a poor light condition or in a nearly featureless indoor environment. The lack of RGB information makes long-range camera pose estimation difficult in a large indoor environment. The key idea of our research is to take advantage of the geometric prior of Manhattan scenes in each stage of the reconstruction pipeline with the specific aim to reduce the cumulative registration error and overall odometry drift in a long sequence. This idea is further boosted by local Manhattan frame growing and the local-to-global strategy that leads to implicit loop closure handling for a large indoor scene. Our proposed pipeline, namely ManhattanFusion, starts with planar alignment and local pose optimization where the Manhattan constraints are imposed to create detailed local segments. These segments preserve intrinsic scene geometry by minimizing the odometry drift even under complex and long trajectories. The final model is generated by integrating all local segments into a global volumetric representation under the constraint of Manhattan frame-based registration across segments. Our algorithm outperforms others that use depth data only in terms of both the mean distance error and the absolute trajectory error, and it is also very competitive compared with RGB-D based reconstruction algorithms. Moreover, our algorithm outperforms the state-of-the-art in terms of the surface area coverage by 10-40 percent, largely due to the usefulness and effectiveness of the Manhattan assumption through the reconstruction pipeline.


Asunto(s)
Algoritmos , Gráficos por Computador
5.
Mol Biol Rep ; 38(1): 395-401, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20354907

RESUMEN

Data have increasingly shown that melanoma differentiation associated gene-7 (Mda-7/IL-24) has growth suppression activity and can induce apoptosis in many tumor cells, but to our knowledge there have been few studies about its role in colon cancer. We examined its anti-cancer effect on colon cancer. We constructed a recombinant replication-deficient adenovirus carrying human melanoma differentiation associated gene-7 (Ad-IL-24) and examined its apoptosis-inducing efficacy on the colon cancer HT-29 cell line and on an oxaliplatin-resistant cell line HT-29/oxa, using a combination of flow cytometry, growth suppressive activity by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and xenografts. Furthermore, we tested the suppression activity of Mda-7/IL-24 on vascular endothelial growth factor (VEGF) and microvessel density (MVD), as well as the inductive effect on expression of the growth arrest and DNA damage gene (GADD) in xenograft tumors by immunohistochemistry. Melanoma differentiation associated gene-7 can inhibit the growth of colon cancer cell lines and induced apoptosis in about (5.6±0.3)% of HT-29 cells (P<0.05). Xenograft growth was retarded in vivo in mice treated with melanoma differentiation associated gene-7, but the tumor proliferation rate for this group was not significantly different in comparison to controls (P>0.05). Furthermore, melanoma differentiation associated gene-7 induced expression of a growth arrest and DNA damage (GADD) gene and reduced the expression of both VEGF and MVD in xenograft tumors. This study supports a potential therapeutic effect for melanoma differentiation associated gene-7 on colon cancer.


Asunto(s)
Adenoviridae/genética , Neoplasias del Colon/terapia , Interleucinas/genética , Interleucinas/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias del Colon/irrigación sanguínea , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas Fluorescentes Verdes/metabolismo , Células HT29 , Humanos , Inmunohistoquímica , Interleucinas/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neovascularización Patológica/complicaciones , Neovascularización Patológica/tratamiento farmacológico , Compuestos Organoplatinos/farmacología , Compuestos Organoplatinos/uso terapéutico , Oxaliplatino , Transducción Genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Zhonghua Jie He He Hu Xi Za Zhi ; 34(6): 413-8, 2011 Jun.
Artículo en Zh | MEDLINE | ID: mdl-21781511

RESUMEN

OBJECTIVE: To study the radiosensitivity of the recombinant adenoviral vector (called Ad-ING4-IL-24) carrying and co-expressing inhibitor of growth 4 (ING4) and interleukin-24 (IL-24) to human lung adenocarcinoma and the underlying mechanisms. METHODS: The expression levels of ING4 and IL-24 were detected by Western blot. The growth-suppressing and apoptosis-inducing effect of Ad-ING4-IL-24 combined with radiotherapy on SPC-A-1 lung carcinoma cells were assessed by MTT assay and FCM respectively. The 25 nude mice were randomly divided into 5 groups of 5 mice ecah: PBS group, Ad group, Ad-ING4-IL-24 group, radiotherapy group and joint group (Ad-ING4-IL-24 combined radiotherapy). Mice in all groups except radiotherapy group were intratumorally injected every other day for 6 cycles. The short and long axes of the tumor were measured dynamically, tumor volume was calculated as: V = L × W(2/2), changes in tumor volume were graphed. The human lung carcinoma model was established with SPC-A-1 cells in nude mice. The ratios of tumor-suppression and q were calculated. The expression of Caspase-3, Bcl-2, Bax, VEGF in tumor samples were detected by immunohistochemistry. RESULTS: The expressions of ING4 and IL-24 were successfully expressed in SPC-A-1 cells. MTT assay and FCM showed that the levels of cell-growth inhibition and apoptosis induction in Ad-ING4-IL-24 combined with radiotherapy group [(86.2 ± 0.8)%, (60.9 ± 1.0)%] were higher than in Ad-ING4-IL-24 group [(49.8 ± 0.3)%, (26.3 ± 1.3)%] and in radiotherapy group [(44.4 ± 2.2)%, (33.3 ± 0.8)%] (ratio of cell-growth inhibition, F = 550.88, P < 0.01; ratio of induced apoptosis F = 614.08, P < 0.01). Ad-ING4-IL-24 combined with radiotherapy showed an enhanced radiosensitivity effect on human lung adenocarcinoma (q = 1.20). In Ad-ING4-IL-24 group, radiotherapy group and Ad-ING4-IL-24 combined with radiotherapy group, the weight inhibition ratio was 49.5% (5 nude mice), 35.4% (5 nude mice), 79.8% (5 nude mice) respectively. Ad-ING4-IL-24 combined with radiotherapy had a synergetic and enhanced radiosensitivity effect on inhibiting the growth of transplanted tumor (q = 1.18). According to immunohistochemistry, Ad-ING4-IL-24 was shown to up-regulate the expression of Bax and Caspase-3 but down-regulate the expression of Bcl-2 and VEGF. CONCLUSION: Ad-ING4-IL-24 had an enhanced radiosensitivity effect on human lung adenocarcinoma, and therefore acted as a radiotherapy sensitizer, which may be related to its effect on apoptosis-induction and antiangiogenesis.


Asunto(s)
Proteínas de Ciclo Celular/farmacología , Terapia Genética , Proteínas de Homeodominio/farmacología , Interleucinas/farmacología , Fármacos Sensibilizantes a Radiaciones/farmacología , Proteínas Supresoras de Tumor/farmacología , Adenocarcinoma/radioterapia , Adenocarcinoma del Pulmón , Adenoviridae/genética , Animales , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Vectores Genéticos , Proteínas de Homeodominio/genética , Humanos , Interleucinas/genética , Neoplasias Pulmonares/radioterapia , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Transfección , Proteínas Supresoras de Tumor/genética
7.
Cancer Invest ; 28(6): 598-607, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20210523

RESUMEN

Previous studies have shown that interleukin-17F (IL-17F) can markedly inhibit the angiogenesis of endothelial cells, implying that it may play a role in antiangiogenic therapy for tumors. To explore its effect on antiangiogenic therapy for hepatocellular carcinoma (HCC), we constructed a recombinant retrovirus vector RV-IL-17F expressing IL-17F, transfected SMMC-7721 human hepatocarcinoma cells with RV-IL-17F, and investigated the effect of transgene IL-17F expression on human hepatocarcinoma cells in vitro and in vivo in animal model. We demonstrated that IL-17F expression exerted no direct effect on in vitro proliferation and cell cycle of SMMC-7721 hepatocarcinoma cells, while it downregulated IL-6, IL-8, and VEGF expression in SMMC-7721 cells at both protein and mRNA levels and IL-17F-expressing supernatant from SMMC-7721/RV-IL-17F directly inhibited ECV304 vascular endothelial cell growth. Moreover, SMMC-7721/RV-IL-17F exhibited a significant decrease in tumor size and microvessel density as compared to the SMMC-7721/RV control when transplanted in nude mice. This retarded tumor growth in vivo elicited by IL-17F was associated with direct suppression of vascular endothelial cells and reduced expression of proangiogenic factors IL-6, IL-8, and VEGF leading to the inhibition of tumor angiogenesis. Thus, our results indicate that IL-17F, a novel antiangiogenic factor, may be useful in antiangiogenic therapy for HCC.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Proliferación Celular , Interleucina-17/metabolismo , Neoplasias Hepáticas/metabolismo , Neovascularización Patológica/prevención & control , Animales , Carcinoma Hepatocelular/irrigación sanguínea , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Ciclo Celular , Línea Celular , Regulación hacia Abajo , Células Endoteliales/metabolismo , Células Endoteliales/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Interleucina-17/genética , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Ratones , Ratones Desnudos , Microvasos/metabolismo , Microvasos/patología , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , ARN Mensajero/metabolismo , Factores de Tiempo , Transfección , Carga Tumoral , Factor A de Crecimiento Endotelial Vascular/metabolismo
8.
Cancer Invest ; 28(1): 85-93, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19916746

RESUMEN

Previous studies have demonstrated that interleukin-24 [IL-24; originally called melanoma differentiation associated gene-7 (mda-7)] as a novel tumor suppressor gene has tumor-suppressive activity against a broad spectrum of human cancers. However, the therapeutic effect of the recombinant human IL-24 (rhIL-24) protein purified from prokaryotic cells on gastric cancer has not been reported. In this study, we purified soluble rhIL-24 using Q-Sepharose column after the denaturing and renaturing process from the protein of Escherichia coli BL21 transfected with pET-21a(+)-hIL-24 vector and treated by isopropyl-beta-D-1-thiogalactopyranoside (IPTG) for enhanced expression of transgene rhIL-24. We demonstrated that rhIL-24 was capable of inducing in vitro apoptosis of SGC7901 gastric cancer cells and activating peripheral blood mononuclear cellsto secrete cytokines such as IL-6, TNF-alpha, and IFN-gamma. We also showed that rhIL-24 was able to inhibit formation of blood capillaries on chicken embryonic allantois and in vivo tumor angiogenesis leading to suppressing SGC7901 gastric cancer cell growth in vitro and in vivo possibly due to its downregulation of Bcl-2/Bax ratio, VEGF (vascular endothelial growth factor), and CD34. Therefore, our results indicate that rhIL-24 has potent suppressive effect on human SGC7901 gastric carcinoma cell line and warrant its further investigation for therapeutic application against gastric cancer.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma/tratamiento farmacológico , Interleucinas/farmacología , Neoplasias Gástricas/tratamiento farmacológico , Inhibidores de la Angiogénesis/farmacología , Animales , Antígenos CD34/metabolismo , Apoptosis/efectos de los fármacos , Carcinoma/irrigación sanguínea , Carcinoma/metabolismo , Carcinoma/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Clonación Molecular , Citocinas/metabolismo , Humanos , Interleucinas/genética , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Masculino , Ratones , Ratones Desnudos , Neovascularización Patológica/patología , Neovascularización Patológica/prevención & control , Neovascularización Fisiológica/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Recombinantes/farmacología , Neoplasias Gástricas/irrigación sanguínea , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Factores de Tiempo , Carga Tumoral/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína X Asociada a bcl-2/metabolismo
9.
Curr Ther Res Clin Exp ; 71(6): 384-97, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24688157

RESUMEN

BACKGROUND: Griseofulvin, an oral nontoxic antifungal drug, has been reported to possess anticancer effect in human cancer cells, while the mechanisms are not completely understood. OBJECTIVE: The aim of this study was to investigate the cytotoxic effect of griseofulvin on K562 cells and to understand its underlying molecular pathways. METHODS: K562 cells were treated with griseofulvin at different concentrations for 24 hours, and the inhibition effect of griseofulvin on K562 cell proliferation was assessed by tetrazolium salt colorimetric assay. Apoptosis was assessed by examining nuclear morphology and quantifying phosphatidylserine externalization, and alterations in cellular morphology were analyzed by laser scanning confocal microscopy for fluorescent analysis. Flow cytometry was used in the analysis of cell cycle, mitochondrial membrane potential, and caspase pathways. RESULTS: Griseofulvin could inhibit the growth of K562 cells in a dose-dependent manner with a mean (SD) inhibitory concentration of 50% value of 15.38 (1.35) µg/mL compared with untreated controls. Apoptosis was induced in K562 cells (38.35% [2.73%]; P < 0.01) by griseofulvin with the observation of both an increase in phosphatidylserine level and accumulation of chromatin nucleation in griseofulvintreated cells. In addition, cell-cycle analysis using propidium iodide staining suggested a significant G2/M accumulation (increase from mean 17.64% [4.49%] to 48.29 [1.89%]; P < 0.01) as a result of griseofulvin treatment. Flow cytometry analysis found that griseofulvin treatment was associated with the depolarization of the mitochondrial membrane in K562 cells. Furthermore, increased activities of caspase-3 by 22.15-fold (P < 0.01) and caspase-9 by 16.73-fold (P < 0.01) were observed in K562 cells after griseofulvin treatment compared with the untreated control; a decrease of caspase-8 activity was also observed, but the change was not statistically significant. CONCLUSIONS: These findings suggest that griseofulvin inhibited growth of K562 cells and induced cell apoptosis through cell-cycle arrest and mitochondrial membrane potential decrease as well as caspase-3 and -9 activation. Further testing is needed to evaluate the potential of griseofulvin as a candidate in the chemotherapy of hematologic malignancies.

10.
Zhonghua Yan Ke Za Zhi ; 45(11): 992-8, 2009 Nov.
Artículo en Zh | MEDLINE | ID: mdl-20137417

RESUMEN

OBJECTIVE: The purpose of this research was to study the influence of the regenerated silk fibroin film (SF) on cytokines expression of transfected human corneal epithelial cells (HCECs) and to investigate the possibility of constructing biomaterial complex using SF, modified by transgenic cells. METHODS: Empirical study.Ad-VEGF(165) was injected into the limbus of a rabbit's cornea to induce cornea neovascularization (CNV). CNV was evaluated by growth areas and VEGF characteristic was evaluated by immunohistochemistry. HCECs was cultivated on silk protein membrane in the cell cultivation plate. Modality of cells, activity of cell proliferation and infection efficiency of Ad-VEGF(165) were monitored to evaluate the biocompatibility of silk fibroin. The angiogenesis-related cytokines in the cell cultivation supernatant was measured using ELISA method such as vascular endothelial growth factor (VEGF), angiogenin 1 (Ang1), epidermal growth factor (EGF) and transforming growth factor-beta (TGF-beta) in the supernatant (Two-way analysis of variance). RESULTS: (1) The area of corneal neovascularization was observed to be (7.60 +/- 1.12) mm(2) at 1 week after Ad-VEGF(165) was injected and it became (12.28 +/- 2.54) mm(2) another three weeks later. Positive expression of VEGF in corneal stromal was observed by immunohistochemistry at 3 d, 1 week and 1 month after injection. (2) There was no difference noticed in amorphous, growth curve and infection efficiency of Ad-VEGF(165) between both cells culture conditions of silk protein membrane and plate cultivation. (3) After transfection, the concentration of VEGF, Ang1, EGF and TGF-beta expressions in the corneal epithelium cell cultivation supernatant with silk protein membrane as carriers was (721.67 +/- 66.97) ng/L, (1042.67 +/- 315.81) ng/L, (2421.00 +/- 0.00) ng/L, and (313.33 +/- 34.06) ng/L respectively; and the concentration of each of the aforementioned expression was (721.67 +/- 66.97) ng/L, (860.33 +/- 315.81) ng/L, (1960.33 +/- 797.90) ng/L, and (278.00 +/- 53.11) ng/L without using silk protein membrane as carriers. The increase of VEGF (F = 168.16, P < 0.0001), EGF (F = 52.76, P < 0.0001), Ang1 (F = 12.47, P = 0.001), and TGF-beta (F = 0.008, P = 0.932) in the Ad-VEGF(165) group was considered statistically significant; however, there was no evident change in the concentration of VEGF (F = 0.071, P = 0.793), EGF (F = 0.563, P = 0.465), Ang1 (F = 0.14, P = 0.714), and TGF-beta (F = 0.008, P = 0.932)expressions in the corneal epithelium cell cultivation supernatant both with or without using silk protein membrane as carriers. CONCLUSION: Same as cell HCECs culturing in the cultivation plate, through SF application, VEGF(165) destination gene could be high-level expressed in the supernatant having which the HCECs is cultured on SF, and in addition, the angiogenesis-related cytokines content of Ang1, EGF, and TGF-beta autocrine in the HCECS cultivation supernatant could be high-level expressed as well.


Asunto(s)
Epitelio Corneal/metabolismo , Fibroínas/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adenoviridae/genética , Animales , Materiales Biocompatibles , Técnicas de Cultivo de Célula , Células Epiteliales/metabolismo , Humanos , Proteínas de la Membrana/metabolismo , Conejos , Transfección , Factor A de Crecimiento Endotelial Vascular/genética
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 26(1): 110-5, 2009 Feb.
Artículo en Zh | MEDLINE | ID: mdl-19334567

RESUMEN

As a biomaterial to be used for reparation in the case of trauma, the silk fibroin, particularly its effect on the transcription and expression of VEGF gene, is a concern. In this study, the ECV304 cell's growth shape and growth curve on the regenerated silk fibroin film were observed, and its VEGF secretion level was measured by ELISA test. It was found that the regenerated silk fibroin film did not interfere with ECV304 cell's growth and function. The L929 cell transfected with human VEGF gene grew on the regenerated silk fibroin film; the real-time quantitative RT-PCR method and ELISA test were used for detecting the transcription and expression of VEGF gene. The results showed the regenerated silk fibroin film did not interfere with the transcription and expression of VEGF gene. Therefore, the regenerated silk fibroin film is a safe biomaterial for inducing vascularization with no untoward effect on the reparation of trauma.


Asunto(s)
Materiales Biocompatibles , Células Endoteliales/metabolismo , Fibroínas/farmacología , Seda , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Materiales Biocompatibles/farmacología , Línea Celular , Células Endoteliales/citología , Humanos , Seda/farmacología , Transcripción Genética , Factor A de Crecimiento Endotelial Vascular/genética
12.
J Mater Chem B ; 7(1): 80-94, 2019 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-32254952

RESUMEN

The angiogenesis of an implanted construct is among the most important issues in tissue engineering. In this study, spermine was used to modify Bombyx mori silk fibroin (BSF) to synthesize cationized BSF (CBSF). BSF and CBSF were coated in sequence on the surface of polyethyleneimine (PEI)/vascular endothelial growth factor 165/angiopoietin-1 coexpression plasmid DNA (pDNA) complexes to form CBSF/BSF/PEI/pDNA quaternary complexes. BSF scaffolds loaded with carrier/pDNA complexes were prepared as dermal regeneration scaffolds by freeze-drying. In one set of experiments, scaffolds were used to cover a chick embryo chorioallantoic membrane (CAM) to investigate the influence of carrier/pDNA complexes on angiogenesis; in another set of experiments, scaffolds were implanted into dorsal full-thickness wounds in Sprague-Dawley rats to evaluate the effect of carrier/pDNA complex-loaded BSF scaffolds on neovascularization and dermal tissue regeneration. After modification with spermine, the surface zeta potential value of BSF rose to +11 mV from an initial value of -9 mV, and the isoelectric point of BSF increased from 4.20 to 9.04. The in vitro transfection of human umbilical vein endothelial cells (EA.hy926) with quaternary complexes revealed that the CBSF/BSF/PEI/pDNA complexes clearly exhibited lower cytotoxicity and higher transfection efficiency than the PEI/pDNA complexes. The CAM assay showed a more abundant branching pattern of blood vessels in BSF scaffolds loaded with CBSF/BSF/PEI/pDNA complexes than in BSF scaffolds without complexes or loaded with PEI/pDNA complexes. The in vivo experimental results demonstrated that the incorporation of CBSF/BSF/PEI/pDNA complexes could effectively enhance angiogenesis in the implanted BSF scaffolds, thereby promoting the regeneration of dermal tissue, providing a new scaffold for the regeneration of dermal tissue and other tissues containing blood vessels.


Asunto(s)
Dermis/fisiología , Fibroínas , Regeneración/fisiología , Ingeniería de Tejidos , Angiopoyetina 1/genética , Animales , Bombyx/metabolismo , Cationes/química , Embrión de Pollo , Dermis/irrigación sanguínea , Fibroínas/química , Fibroínas/farmacología , Proteínas Fluorescentes Verdes/genética , Células Endoteliales de la Vena Umbilical Humana , Humanos , Masculino , Neovascularización Fisiológica/fisiología , Plásmidos , Polietileneimina/química , Ratas , Ratas Sprague-Dawley , Transfección , Factor A de Crecimiento Endotelial Vascular/genética
13.
Front Neurosci ; 12: 943, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30618572

RESUMEN

One of the most exciting areas of rehabilitation research is brain-controlled prostheses, which translate electroencephalography (EEG) signals into control commands that operate prostheses. However, the existing brain-control methods have an obstacle between the selection of brain computer interface (BCI) and its performance. In this paper, a novel BCI system based on a facial expression paradigm is proposed to control prostheses that uses the characteristics of theta and alpha rhythms of the prefrontal and motor cortices. A portable brain-controlled prosthesis system was constructed to validate the feasibility of the facial-expression-based BCI (FE-BCI) system. Four types of facial expressions were used in this study. An effective filtering algorithm based on noise-assisted multivariate empirical mode decomposition (NA-MEMD) and sample entropy (SampEn) was used to remove electromyography (EMG) artifacts. A wavelet transform (WT) was applied to calculate the feature set, and a back propagation neural network (BPNN) was employed as a classifier. To prove the effectiveness of the FE-BCI system for prosthesis control, 18 subjects were involved in both offline and online experiments. The grand average accuracy over 18 subjects was 81.31 ± 5.82% during the online experiment. The experimental results indicated that the proposed FE-BCI system achieved good performance and can be efficiently applied for prosthesis control.

14.
World J Gastroenterol ; 13(47): 6425-32, 2007 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-18081234

RESUMEN

AIM: To study the effectiveness and mechanisms of anti- human vascular endothelial growth factor (hVEGF) hairpin ribozyme on angiogenesis, oncogenicity and tumor growth in a hepatocarcinoma cell line and a xenografted model. METHODS: The artificial anti-hVEGF hairpin ribozyme was transfected into hepatocarcinoma cell line SMMC-7,721 and, subsequently, polymerase chain reaction (PCR) and reverse transcription polymerase chain reaction (RT-PCR) were performed to confirm the ribozyme gene integration and transcription. To determine the effects of ribozyme ,VEGF expression was detected by semiquantitative RT-PCR and enzyme liked immunosorbent assay (ELISA). MTT assay was carried out to measure the cell proliferation. Furthermore,the transfected and control cells were inoculated into nude mice respectively, the growth of cells in nude mice and angiogenesis were observed. RESULTS: VEGF expression was down-regulated sharply by ribozyme in transfected SMMC-7,721 cells and xenografted tumor. Compared to the control group, the transfected cells grew slower in cell cultures and xenografts, and the xenograft formation was delayed as well. In addition, the microvessel density of the xenografted tumor was obviously declined in the transfected group. As demonstrated by microscopy,reduction of VEGF production induced by ribozyme resulted in a significantly higher cell differentiation and less proliferation vigor in xenografted tumor. CONCLUSION: Anti-hVEGF hairpin ribozyme can effectively inhibit VEGF expression and growth of hepatocarcinoma in vitro and in vivo. VEGF is functionally related to cell proliferation, differentiation and tumori-genesis in hepatocarcinoma.


Asunto(s)
Carcinoma Hepatocelular/prevención & control , Terapia Genética/métodos , Neoplasias Hepáticas Experimentales/prevención & control , Neovascularización Patológica/prevención & control , ARN Catalítico/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Animales , Carcinoma Hepatocelular/irrigación sanguínea , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Diferenciación Celular , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Ensayo de Inmunoadsorción Enzimática , Exones , Femenino , Humanos , Inmunohistoquímica , Neoplasias Hepáticas Experimentales/irrigación sanguínea , Neoplasias Hepáticas Experimentales/genética , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Microcirculación/metabolismo , Microcirculación/patología , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo , Transcripción Genética , Transfección , Factor A de Crecimiento Endotelial Vascular/genética , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Sheng Li Xue Bao ; 58(6): 521-8, 2006 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-17173186

RESUMEN

Paf1 complex was identified in yeast and characterized to function in transcription and its related events. We identified the Drosophila homological components of paf1, CDC73 and RTF1 of paf1 complex. The genes encoding Drosophila paf1, CDC73 and RTF1 were cloned and expressed. With the purified recombinant proteins of truncated components of paf1 complex, antibodies against the Drosophila paf1, CDC73 and RTF1 were generated. These antibodies have been shown to be able to detect the endogenous paf1 subunits as well as their human counterparts in the HeLa extract. On Drosophila polytene chromosomes, these antibodies have been demonstrated to locate the paf1 complex at actively transcribing sites, which co-localized with phosphorylated RNA polymerase II, indicating that paf1 complex in Drosophila is involved in transcription or the events coupling with transcription.


Asunto(s)
Anticuerpos/química , Proteínas de Drosophila/inmunología , Drosophila melanogaster , Animales
16.
Robotics Biomim ; 3: 7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27330932

RESUMEN

This paper proposes and implements an open framework of active auditory learning for a home service robot to serve the elderly living alone at home. The framework was developed to realize the various auditory perception capabilities while enabling a remote human operator to involve in the sound event recognition process for elderly care. The home service robot is able to estimate the sound source position and collaborate with the human operator in sound event recognition while protecting the privacy of the elderly. Our experimental results validated the proposed framework and evaluated auditory perception capabilities and human-robot collaboration in sound event recognition.

17.
Int J Nanomedicine ; 11: 1013-23, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27042056

RESUMEN

The development of a novel cationized polymer used as a gene delivery carrier that can conveniently and effectively transfect cells resulting in a stably expressed target gene remains a challenge. Antheraea pernyi silk fibroin (ASF) is a cytocompatible and biodegradable natural polymer, and it possesses Arg-Gly-Asp sequences but a negative charge. In order to render ASF amenable to packaging plasmid DNA (pDNA), spermine was used to modify ASF to synthesize cationized ASF (CASF), which was used as a gene delivery carrier. CASF was characterized using trinitrobenzene sulfonic acid assay, the zeta potential determination, and a Fourier transform infrared analysis, and the results of these characterizations indicated that the -NH2 in spermine effectively reacts with the -COOH in the side chains of ASF. Spermine grafted to the side chains of ASF resulted in the conversion of the negative charge of ASF to a positive charge. CASF packaged pDNA and formed CASF/pDNA complexes, which exhibited spherical morphology with average particle sizes of 215-281 nm and zeta potential of approximately +3.0 mV to +3.2 mV. The results of the MTT assay, confocal laser scanning microscopy, and flow cytometry analysis in a human endothelial cell line revealed that CASF/pDNA complexes exhibited lower cytotoxicity and higher transfection efficiency compared to the pDNA complexes of polyethyleneimine. These results indicate that our synthesized CASF, a cationized polymer, is a potential gene delivery carrier with the advantages of biodegradability and low cytotoxicity.


Asunto(s)
Portadores de Fármacos/química , Fibroínas/química , Mariposas Nocturnas/química , Polietileneimina/química , Espermina/química , Transfección , Animales , Línea Celular , ADN/química , ADN/genética , Humanos , Tamaño de la Partícula , Plásmidos/genética
18.
Chin J Traumatol ; 8(5): 306-10, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16176763

RESUMEN

OBJECTIVE: To culture olfactory ensheathing cells (OECs) of rats in vitro and to investigate its morphology, mitosis and immunocytochemistry, and to explore if the OECs could be a new donation for transplantation. METHODS: OECs were harvested from olfactory mucosa of Sprague Dawley rats based on the differing rates of attachment of the various cell types, followed by glial fibrillary acidic protein (GFAP), nerve growth factor (NGF), anti-low affinity receptor for NGF (NGFRp75), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and S-100 immunocytochemistry. The morphological changes and mitosis were observed under a phase contrast microscope at different culture time. RESULTS: Three morphologically distinct types of cells, bipolar, multipolar and flat morphology were present in the primary culture of adult rat olfactory mucosa. Mitosis was characterized by a retraction of all processes, forming a sphere that divided into spherical daughter cells, the daughter cells sent out their processes. The OECs were immunoreactive for GFAP, NGFRp75, S-100, NGF, BDNF and NT-3. CONCLUSIONS: The OECs from nasal olfactory mucosa cultivated in the medium with fetal bovine serum could survive, divide, differentiate, and express the neurotrophin. It may become an accessible source for autologous grafting in spinal cord injury.


Asunto(s)
Mucosa Olfatoria/citología , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Inmunohistoquímica , Masculino , Mitosis , Mucosa Olfatoria/trasplante , Ratas , Ratas Sprague-Dawley
19.
IEEE Trans Cybern ; 45(10): 2030-41, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25373136

RESUMEN

This paper presents an integrated learning framework that enables humanoid robots to perform human-robot collaborative manipulation tasks. Specifically, a table-lifting task performed jointly by a human and a humanoid robot is chosen for validation purpose. The proposed framework is split into two phases: 1) phase I-learning to grasp the table and 2) phase II-learning to perform the manipulation task. An imitation learning approach is proposed for phase I. In phase II, the behavior of the robot is controlled by a combination of two types of controllers: 1) reactive and 2) proactive. The reactive controller lets the robot take a reactive control action to make the table horizontal. The proactive controller lets the robot take proactive actions based on human motion prediction. A measure of confidence of the prediction is also generated by the motion predictor. This confidence measure determines the leader/follower behavior of the robot. Hence, the robot can autonomously switch between the behaviors during the task. Finally, the performance of the human-robot team carrying out the collaborative manipulation task is experimentally evaluated on a platform consisting of a Nao humanoid robot and a Vicon motion capture system. Results show that the proposed framework can enable the robot to carry out the collaborative manipulation task successfully.


Asunto(s)
Inteligencia Artificial , Sistemas Hombre-Máquina , Robótica , Análisis y Desempeño de Tareas , Cibernética , Humanos , Reproducibilidad de los Resultados , Programas Informáticos
20.
Technol Cancer Res Treat ; 14(4): 369-78, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25326586

RESUMEN

The inhibitor of growth (ING) family proteins have been defined as candidate tumor suppressors. ING4 as a novel member of ING family has potential tumor-suppressive effects via multiple pathways. However, the therapeutic effect of adenovirus-mediated ING4 (Ad-ING4) gene transfer in human osteosarcoma is still unknown. In this study, we explored the in vitro and in vivo antitumor activity of Ad-ING4 in human osteosarcoma and its potential mechanism using a MG-63 human osteosarcoma cell line. We demonstrated that Ad-ING4 induced significant growth inhibition and apoptosis, upregulated the expression of P21, P27 and Bax, downregulated the Bcl-2 expression and activated Caspase-3 in MG-63 human osteosarcoma cells. Moreover, intratumoral injections of Ad-ING4 in athymic nude mice bearing MG-63 human osteosarcoma tumors significantly suppressed osteosarcoma xenografted tumor growth, increased the expression of P21, P27 and Bax, reduced the Bcl-2 and CD34 expression and microvessel density (MVD) in tumors. This retarded MG-63 osteosarcoma growth in vitro and in vivo in an athymic nude mouse model elicited by Ad-ING4 was closely associated with the increase in the expression of cell cycle-related molecules P21 and P27, decrease in the ratio of anti- to pro-apoptotic molecules Bcl-2/Bax followed by the activation of Caspase-3 leading to apoptosis via intrinsic apoptotic pathways, and the inhibition of tumor angiogenesis. Thus, our results indicate that Ad-ING4 is a potential candidate for human osteosarcoma gene therapy.


Asunto(s)
Adenoviridae/genética , Apoptosis/genética , Proteínas de Ciclo Celular/genética , Técnicas de Transferencia de Gen , Vectores Genéticos/genética , Proteínas de Homeodominio/genética , Neovascularización Patológica/genética , Osteosarcoma/genética , Osteosarcoma/patología , Proteínas Supresoras de Tumor/genética , Animales , Biomarcadores , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular/genética , Modelos Animales de Enfermedad , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Terapia Genética , Humanos , Masculino , Ratones , Neovascularización Patológica/metabolismo , Neovascularización Patológica/terapia , Osteosarcoma/metabolismo , Osteosarcoma/terapia , Carga Tumoral/genética , Ensayos Antitumor por Modelo de Xenoinjerto
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