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Objective To observe the effects of pigment epithelial-derived factor gene-modified human umbilical cord mesenchymal stem cells (PEDF-MSCs) on the expression of pigment epithelial-derived factor (PEDF) and vascular endothehal growth factor (VEGF) in a rat model of retinal ischemia-reperfusion injury (RIRI) and its protection on retinal ganglion cells.Methods Lentivirus (LV) labeled with green fluorescent protein (GFP) was used as a vector to transfect the PEDF gene into human umbilical cord mesenchymal stem cells (hUCMSCs) at a multiplicity of infection (MOI) of 1,10,20,and 50 in vitro,and then the expression of PEDF gene and protein in cells transfected with the best MOI value was detected by RT-PCR and ELISA.The healthy male SD rats were randomly divided into normal group (N group) and experimental group.The RIRI model was made by high intraocular pressure in the experimental group,and the RIRI rats with PBS treatment were allocated as the PBS group,with hUC-MSCs treatment as M group and LV-PEDF-MSCs treatment as P group,and the N group was left untreated.All rats were sacrificed on day 5,and the number of retinal ganglion cells were counted by Nissl staining,the thickness of the retina was calculated,as well as the expression of PEDF and VEGF mRNA in rat retina was detected by RT-PCR.Results The transfection efficiency was as high as 75.8％ under fluorescence microscope.The results of RT-PCR showed that the relative expression of PEDF mRNA in PEDF-MSCs supernatant (4.34 ± 0.29) was significantly higher than that in hUCMSCs (1.08 ± 0.15),and the difference was statistically significant (P ＜ 0.05);moreover,the results of ELISA showed that PEDF protein expression in PEDF-MSCs supernatant [(83.09 ± 7.58)μg · L-1] was significantly higher than that in hUCMSCs [(12.30 ±1.24) μg · L-1],and the difference was statistically significant (P ＜ 0.05).Nissl staining results showed that the number of ganglion cells in group PBS decreased after model establishment.After 5 days of treatment,the number of ganglion cells in P group and M group was higher than that in PBS group,and the difference was statistically significant (both P ＜ 0.05);and P group was higher than M group,with the significant difference (P ＜ 0.05).And this was true of the thickness of the retina.RT-PCR showed that the expression of PEDF mRNA in P group was significantly up-regulated,but VEGF mRNA expression was significantly down-regulated,and the differences were statistically significant when compared with PBS and M group (both P ＜ 0.05).Conclusion Intravitreal injection of PEDF-MSCs can up-regulate the expression of PEDF but down-regulate the expression of VEGF in the retina of RIRI rats,which can protect the retinal ganglion cells against RIRI.
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BACKGROUND: Owing to the advantages of low sensitization and natural three-dimensional structure, good biocompatibility and cell affinity, acellular heart scaffold materials are of great current interest in cardiac tissue engineering. OBJECTIVE: To investigate the cytocompatibility of an acellular heart scaffold of neonatal rats. METHODS: In order to construct the seed cell-scaffold complex, passage 3 bone marrow mesenchymal stem cells (BMSCs) of Sprague-Dawley neonatal rats were cultured with an acellular heart scaffold of Sprague-Dawley neonatal rats for 7 and 14 days. Hematoxylin eosin staining and scanning electron microscopy were used to observe the growth of BMSCs in the scaffold. The cell-scaffold complex was induced in myocardial tissue lysate for 14 days. BMSCs with planar orientation differentiation for 14 and 20 days were used as control group. RT-PCR was used to detect the expression of myosin heavy chain α-MHC and zinc finger transcription factor GATA-4 in BMSCs. RESULTS AND CONCLUSION: (1) Hematoxylin-eosin staining showed the acellular heart scaffold contained a large number of eosinophilic fibrous structures, and the cell number of cell-scaffold complex after co-culture for 14 days was higher than that after co-culture for 7 days. Under the scanning electron microscope, a large amount of cells adhered to the fiber surface of the acellular scaffold at 14 days of co-culture. (2) BMSCs with planar orientation differentiation for 14 and 20 days had the bamboo-like and myotube-like structures. In the cell-scaffold complex with planar orientation differentiation for 14 days, the expression of α-MHC and GATA-4 could be detected, and their expression levels fulfilled the requirement for the presence of bamboo-like cells and myotube-like structure. These results indicate that the acellular heart scaffold exhibits good cytocompatibility.
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Objective To investigate the effects of PRL-3 shRNA mediated by lentivirus on proliferation, invasion and apoptosis of human colorectal cancer SW480 cells. Methods There were three experimental groups in this study, which included blank control group, negative control group and transfected group. Colorectal cancer SW480 cells were transfected with lentiviral interference vector carrying PRL-3 shRNA to build a stable PRL-3-silencing cell line. The expression of PRL-3 mRNA was detected by real-time quantitative polymerase chain reaction (real-time PCR). Cell proliferation was analyzed by MTT method and colony formation assay.Invasion and migration were measured by Transwell assay and invasion chamber. Apoptosis rate was performed by flow cytometry. Results The stable PRL-3-silencing cell line was successfully constructed.Compared with the blank control group and negative control group,the relative expression levels of PRL-3 mRNA were reduced in transfected group after transfection with PRL-3 shRNA(P<0.05),but there was no significant difference between the blank control group and the negative control group.After transfection with PRL-3 shRNA for 72 h,the proliferation of SW480 cells was significantly lower in transfected group than that of the blank control group and the negative control group,and the proliferation decreased significantly in 120 h(P<0.05).Compared with the blank control group and negative control group, the ability of colony formation was also weakened in the transfected group (P<0.05). Compared with the blank control group and negative control group,the migration and invasion ability were decreased in the transfected group(P<0.05),and the apoptosis rate was increased in the transfected group(P<0.05).Conclusion PRL-3 shRNA can inhibit the expression of PRL-3 and the proliferation, promote the apoptosis of SW480, which indicates that PRL-3 may become a target for colorectal carcinoma treatment.
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To achieve fast and accurate analysis of weak current signal of nanopore-based single molecule detection, we designed a real-time adaptive threshold data processing algorithm with data buffering technique and finite impulse response filtering. The system, which is designed based on the data processing algorithm, could realize real-time recognition and analysis of nanopore events during the data recording process. In order to verify the performance of the system, the ideal signals with different noise level (20-100 pA) and recording bandwidth (3 - 100 kHz) was generated. The results showed that the system was stable to analyze the generated signals even at high noise. In addition, the system was also suitable for the data recording conditions of low bandwidth and high sampling rate (250 kHz). The proposed nanopore data processing system was further applied in the Aerolysin nanopore experiment for the detection of poly(dA) 4 molecules. The results showed that the data processing system could be applied in real nanopore recording system with high accuracy and speed.
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Objective: To investigate the influence of esculentoside A（EsA） on production of IL-1 and TNF by rabbit synovial cells induced by LPS. Methods: levels of IL-1 and TNF in the supernatant of rabbit synovial cell were determined by examining proliferation of thymic cells and by bioassay L929 cells as target cells, respectively. Results: EsA in 5-40 μg/ml could significantly inhibit the production of IL-1 and TNF from rabbit synovial cells induced by LPS. Conclusion: EsA can inhibit the production of IL-1 and TNF from synovial cells. It suggests that EsA may play a role in improving the rheumatoid arthritis.
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Objective: To investigate the influence of esculentoside A（EsA） on production of IL-1 and TNF by rabbit synovial cells induced by LPS. Methods: levels of IL-1 and TNF in the supernatant of rabbit synovial cell were determined by examining proliferation of thymic cells and by bioassay L929 cells as target cells, respectively. Results: EsA in 5-40 μg/ml could significantly inhibit the production of IL-1 and TNF from rabbit synovial cells induced by LPS. Conclusion: EsA can inhibit the production of IL-1 and TNF from synovial cells. It suggests that EsA may play a role in improving the rheumatoid arthritis.