Objective To investigate the feasibility of intramuscular gene therapy for acute arterial ischemic diseases by use of plasmid pcDNA3-VEGF121 and to evaluate therapeutic efficiency of vascular endothelial growth factor(VEGF) by different routes of administration. Methods Fifty New Zealand White rabbits were randomly assigned to either gelation sponge carryingpcDNA3-VEGF121 (n=18), intramuscular injectionpcDNA3-VEGF121 (n=18), or pcDNA3 (as control group,n=14). After ligation of the external iliac artery and complete excision of the femoral artery, 500 μg of the plasmid pcDNA 3-VEGF121 were transfected into the muscles of the ischemic limb by gelation sponge carrying or direct intramuscular-injection. Immediately after gene transfection, blood flow of the internal iliac artery were measured. VEGF121gene expression was detected by RT-PCR after 2 days, 1 week, 2 weeks, 3 weeks and 4 weeks of transfection. After 30 days, blood flow of the internal iliac artery, angiographic score and histologicalvessels of ischemic hindlimbs were measured respectively. Results In the two VEGF-treated groups, VEGF121 mRNA expressed in the transfected ischemic muscles after 2 days and lasted 2 weeks. Immediately after gene transfection, blood flow of the internal iliac artery had no significant difference between three groups. After 30 days, blood flow of the internal iliac artery, angiographicscore and capillary density were significantly greater in both VEGF-treated groups than in control group. Complexity of vascular branching and vessel density of gelation sponge-VEGF treated limbs were significantly greater when comparedwith the intramuscular-injection limbs. Conclusion These findings suggest the feasibility of employing gene therapy of pcDNA3-VEGF121could augmentcollatal development and tissue perfusion in an animal model of hindlimb ischemia, andgelation sponge carrying VEGF gene may respect a potential therapy methods.
ObjectiveTo explore the biological functions of Kip1 ubiquitylation-promoting complex 2 (KPC2) in the repair process of spinal cord injury (SCI) by studying the expression and cellular localization of KPC2 in rat SCI models. MethodsFifty-six adult Sprague-Dawley rats were randomly divided into 2 groups: in the control group (n=7), simple T9 laminectomy was performed;in the experimental group (n=49), the SCI model was established at T9, 7 rats were used to detect follow indexs at 6 hours, 12 hours, 1 day, 3 days, 5 days, 7 days, and 14 days after SCI. Western blot analysis was used to detect the protein expressions of P27kip1, KPC2, CyclinA and proliferating cell nuclear antigen (PCNA) after SCI. Immunohistochemistry was used to observed the cellular localization of KPC2 after SCI, double-labeling immunofluorescence staining to observe the co-localization of KPC2 with neuronal nuclei (NeuN), glial fibrillary acidic protein (GFAP) and PCNA. in vitro astrocytes proliferation model was used to further validate these results, Western blot to detect KPC2, P27kip1, and PCNA expressions. The interaction of P27kip1, KPC1, and KPC2 in cell proliferation was analyzed by co-immunoprecipitation. ResultsThe Western blot analysis showed a significant down-regulation of P27kip1 and a concomitant up-regulation of KPC2, CyclinA, and PCNA after SCI. Immunohistochemistry staining revealed a wide distribution of KPC2 positive signals in the gray matter and white matter of the spinal cord. The number of KPC2 positive cells in the experimental group was significantly higher than that in the control group (t=10.982, P=0.000). Double-labeling immunofluorescence staining revealed the number of KPC2/NeuN co-expression cells in the gray matter of spinal cord was (0.43±0.53)/visual field in the control group and (0.57±0.53)/visual field in the experimental group, showing no significant difference (t=0.548, P=0.604);in the white matter of spinal cord, the number of KPC2/PCNA co-expression cells was (3.86±0.90)/visual field in the control group and (0.71±0.49)/visual field in the experimental group, showing significant difference (t=7.778, P=0.000). And then, the number of KPC2/PCNA co-expression cells were (0.57±0.53)/visual field in the control group and (5.57±1.13)/visual field in the experimental group, showing significant difference (t=8.101, P=0.000). Concomitantly, there was a similar kinetic in proliferating astrocytes in vitro. The Western blot analysis showed a significant down-regulation of P27kip1 and a concomitant up-regulation of KPC2 and PCNA after serum stimulated. Co-immunoprecipitation demonstrated increased interactions between P27kip1, KPC1, and KPC2 after stimulation. ConclusionThe up-regulated expression of KPC2 after SCI is related to the down-regulation of P27kip1, this event may be involved in the proliferation of astrocytes after SCI.
The purpose of this paper is to report the research and design of control system of magnetic coupling centrifugal blood pump in our laboratory, and to briefly describe the structure of the magnetic coupling centrifugal blood pump and principles of the body circulation model. The performance of blood pump is not only related to materials and structure, but also depends on the control algorithm. We studied the algorithm about motor current double-loop control for brushless DC motor. In order to make the algorithm adjust parameter change in different situations, we used the self-tuning fuzzy PI control algorithm and gave the details about how to design fuzzy rules. We mainly used Matlab Simulink to simulate the motor control system to test the performance of algorithm, and briefly introduced how to implement these algorithms in hardware system. Finally, by building the platform and conducting experiments, we proved that self-tuning fuzzy PI control algorithm could greatly improve both dynamic and static performance of blood pump and make the motor speed and the blood pump flow stable and adjustable.