The bFGF plays an important role in embryonic development of tendons and ligaments and in the healing of injuried tendons and ligaments. The eukaryotic expression plasmid of rat basic fibroblast growth factor (bFGF) gene was constructed in order to further investigate the bFGF function in molecular regulatory mechanism in the repair of tendons and ligaments and to provide the foundation for the clinical application. The cDNA fragments of bFGF were cloned from the skin of rats by RT-PCR, and recombinated to the pMD18-T vector. The cDNA encoding bFGF was cloned from the pMD18-T vector by RT-PCR, digested with restriction enzyme EcoR:, Pst: and bound to eukaryotic expression plasmid pIRES2-EGFP to construct eukaryotic expression plasmid pIRES2-EGFP-bFGF. The pIRES2-EGFP-bFGF was transfected into the tenocytes by lipid-mediated ransfection technique. MTT test was used to detect the biological activity of bFGF in supernatants after the transfection. The expression of type: and III collagen genes was detected by using RT-PCR. It was verified that the pIRES2-EGFP-bFGF was successfully constructed, and its transfection into tenocytes could significantly enhance the biological activity of bFGF, and increase the expression of type: and III collagen mRNA, suggesting that pIRES2-EGFP-mediated bFGF gene therapy was beneficial to the repair of tendons and ligaments.
To evaluate the safety and efficacy of tirofiban, a specific inhibitor of the platelet glycoprotein llb/llla receptor, in the treatment of unstable angina and myocardial infarction without persistent ST elevation (acute coronary syndrome, ACS), a total of 200 patients were randomly assigned to a heparin group and a tirofiban+heparin group on double-blind basis and the treatment effects of the two protocols on ACS were compared when the patients of both groups were taking aspirin at the same time. The composite primary end-point events consisted of death, myocardial infarction, or refractory ischemia. Our results showed that the frequency of the composite primary end point events in 30 days was lower in tirofiban+heparin group as compared with that of heparin group (13.9% vs 29.3 %, P=0.010). The rates of the other composite end point events in the tirofiban+heparin group were also lower than those in the heparin group in 4.5 days and in 30 days. Bleeding complication occurred in 7.0% of the patients receiving heparin alone and in 12.7% of the patients receiving tirofiban and heparin in combination (P=0.1717). The study showed that the incidence of ischemic events in patients with ACS receiving tirofiban+heparin was lower when compared with that of patients who received only heparin and aspirin, suggesting that tirofiban might be of special value in the treatment of ACS.
In order to investigate the effects of simvastatin on secretion and mRNA expression of interleukin-6 (IL-6) and adiponectin in 3T3-L1 adipocytes, mouse 3T3-L1 adipocytes were stimulated with lipopolysaccharide (LPS). Production and mRNA expression of IL-6 and adiponectin in 3T3-L1 adipocytes were measured using enzyme-linked immunosorbent assay (ELISA) and reverse transcriptase polymerase chain reaction (RT-PCR), respectively. The results showed that simvastatin could significantly suppress LPS-induced IL-6 production and mRNA expression in adipocytes (P<0.05), but increase the LPS-induced adiponectin secretion and mRNA expression in a dose-dependent manner (P<0.05). It was suggested that simvastatin could exert beneficial effects on prevention of obesity-induced metabolic changes in adipocytes.
In order to investigate the immunity of unloaded dendritic cells (DCs) derived from murine bone marrow to preexisting lung melanoma metastases of mice, MO5 were intravenously injected to induce lung metastases in syngeneic C57BL/6 mice. Unloaded GM-CSF DCs, PBS and DCs+SIINFEKEL were subcutaneously injected into the mice, which were divided as experimental group, negative control group and positive control group respectively. Monoclonal antibody was used to deplete NK or T cells separately. The immunity-inhibitory effects on the lung melanoma were observed and the corresponding effector cells were examined. It was found that in the experimental and positive groups, the regression was induced in metastatic nodules in the lungs of tumor-bearing mice, but abrogated by treatment with anti-asialo-GM1 but not anti-CD8. It was concluded that the unloaded DCs could suppress the lung melanoma metastases to some extent, which was mediated by NK cells, and could be used as a potent therapeutic agents for lung tumor.
This study examined the effect of resveratrol on the secretion of vascular endothelial growth factor (VEGF) and subsequent proliferation of human leukemia U937 cells, and explored the mechanisms involved. Human leukemia U937 cells were treated with resveratrol of different concentrations (12.5–200 μmol/L) for different time lengths (12–48 h). The proliferation of the U937 leukemic cells was determined by MTT assay. Apoptosis was observed by Annexin-V-FIFC/PI double staining and flow cytometry (FCM). Cells cycle was analyzed by PI staining and FCM. The content of VEGF was determined by ELISA. Human umbibical vein endothelial cells were examined for vasoformation in vitro after exposures to resveratrol of various concetrations. The results showed that resveratrol inhibited the proliferation of U937 leukemia cells in a dose-and time-dependent manner. Resveratrol induced apoptosis and S-phase cell cycle arrest in human leukemic U937 cells. Resveratrol inhibited the secretion of VEGF in U937 cells. Resveratrol inhibited the vasoformation of human vein endothelial cells in a dose-dependent manner. It was concluded that resveratrol could down-regulate the secretion of VEGF, induce apoptosis and suppress the proliferation of U937 cells.
To establish a better method of primary culture for alveolar epithelial type II cells (AEC II) and to study its bionomics, alveolar epithelial type II cells were isolated by digestion with trypsin and collagenase, which were then purified by plated into culture flask coated with rat immunoglobulin G. The purified AEC II were identified by alkaline phosphatase staining, electron microscopy, immunocytochemical staining of pulmonary surfactant protein A (SPA). The SPA expression and transfection characteristics were compared with those of A549 cell line. The results showed that AEC II could be isolated by digestion with trysin and collagenase and purified by adhesive purification by using IgG, with a yield of about 2–3 × 107, and a purity of about 75%–84%. Cells could be quickly identified with AKP staining. AEC II were different from A549 cell line in terms of SPA expression and transfection characteristics. It is concluded that adhesive purification with IgG can improve the purity of AEC II, and AKP staining is simple in cell identification. AEC II can not be completely replaced by A549 cells in some studies because the differences between them, such as SPA expression.