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The study was designed to synthesize a novel dendritic copolymer composed of polyamidoamine dendrimer G0 as the inner core and poly(L-glutamic acid) grafted low molecular weight polyethylenimine (PGLP) as surrounding arms for gene delivery vector. The molecular structure of PGLP was confirmed by 1H NMR (proton nuclear magnetic resonance spectroscopy). The DNA combination capability of PGLP was examined by gel retardation electrophoresis. The particle sizes and zeta potentials of PGLP/pDNA complexes were determined by dynamic light scattering (DLS). The cytotoxicity of PGLP was evaluated by Cell Counting Kit-8 (CCK-8) and hemolysis assays, which was approved by Research Ethics Committee of the First Affiliated Hospital of Nanchang University. The in vitro transfection efficiency of PGLP was measured by a flow cytometry. The results of physicochemical properties suggested that PGLP could self-assemble with DNA to form complexes with average particle sizes of about 105-200 nm and zeta potentials of about +10 - +28 mV, which could protect DNA from serum degradation. The results of biological properties suggested that PGLP showed more higher transfection efficiencies but lower cytotoxicity than PEI 25K or Lipofectamine 2000 in various cell lines (HEK 293T, HeLa, BEL 7402, RASMC). Importantly, it was found that PGLP/pDNA complexes at w/w = 8 showed more strong serum-resistant capacity than PEI 25K/pDNA complexes. Therefore, PGLP is a promising candidate vector for gene delivery.
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Objective To investigate effect and mechanisms of Liujing Toutong Tablets (LTT) on migraine model rats. Methods Rats were sc injected with nitroglycerin to establish migraine model, effect of LTT on scratching latency and frequency of migraine model rats was investigated; 5-hydroxytryptamine (5-HT), norepinephrine (NE), and dopamine (DA) in brain tissue were detected; And β-endorphin (β-EP), calcitonin gene related pepitde (CGRP), and endothelin (ET) in serum were examined by ELISA; The content of nitric oxide (NO) and activity of nitric oxide synthase (NOS) in serum were examined. Results After sc injected with nitroglycerin in 1 to 3 min, the rats in model group began to scratch its head frequently, scratching latency of rats in high- and low- dose (1.4 and 0.7 g/kg) of LTT group was extended (P < 0.01) and scratching frequency was decreased (P < 0.001); The content of β-EP and ET in serum and DA in brain tissue of rats in high- and low-dose (1.4 and 0.7 g/kg) of LTT group were increased (P < 0.05, 0.01, 0.001), and the content of CGRP and the activity of NOS in serum were decreased (P < 0.05). The content of 5-HT and NE in brain tissue of rats in high- and low- dose (1.4 and 0.7 g/kg) of LTT group had no significant change. Conclusion LTT has a significant therapeutic effect on migraine, and could inhibit contractile response of vascular. The mechanisms may be connected with increasing content of β-EP, ET, DA and decreasing content of CGRP and the activity of NOS.
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Objective To develop neutralizing monoclonal antibodies (MAbs) against H10N8 avian influenza virus hemagglutinin and to identify the binding sites. Methods MAbs against hemagglutinin of H10N8 avian influenza virus were developed by genetic engineering. Neutralizing MAbs were screened by microneutralization assay,and then tested by enzyme-linked immunosorbent assay and Western blot to identity the binding sites.The homology modeling process was performed using Discovery Studio 3.5 software,while the binding epitopes were analyzed by BioEdit software. Results One MAb that could neutralize the H10N8 pseudovirus was obtained and characterized. Analysis about epitopes suggested that the antibody could bind to the HA1 region of hemagglutinin,while the epitopes on antigen were conserved in H10 subtypes.Conclusions One neutralizing antibody was obtained by this research.The MAb may potentially be further developed as a pre-clinical candidate to treat avian influenza H10N8 virus infection.