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Objective: We assessed the phylogenetic relationship of Sugarcane streak mosaic virus (SCSMV) according to NIa sequences, to infer the prevalence and variation of SCSMV and to prevent and control this virus., Methods: Leaf samples with mosaic symptom were collected from sugarcane-growing areas in Yunnan province and the Chinese national nursery of sugarcane germplasm resources (NNSGR). NIa sequences of SCSMV were determined by RT-PCR, and analyzed by Splits Tree, RDP, PhyML and DnaSP softwares, in aspect of phylogenetic, selection, and gene flow., Results: We obtained 23 NIa sequences; clear recombination site was not found in NIa; a novel cluster formed by SCSMV Yunnan isolates determined here was found; strong purifying selection was found in NIa of SCSMV; and the gene flow of SCSMV subpopulations between sugarcane-growing areas in Yunnan province and the NNSGR was not frequent., Conclusion: Similar with P1, HC-Pro and CP genes, SCSMV isolates could be divided into five clusters. NIa of SCSMV Yunnan isolates showed high genetic diversity and clear geographical distribution.

Objective: To construct a recombinant adenoviral vector carrying and co-expressing vascular endothelial growth factor 165 (VEGF165) and stromal cell derived factor 1 (SDF-1) and explore its co-expression in ischemic brain tissue in rats., Methods: The VEGF165 and SDF-1 genes were directionally connected with internal ribosome entry site (IRES). And the double gene co-expression recombinant shuttle plasmid pDC316-VEGF165-IRES-SDF-1 was built with homologous recombination. The resultant plasmid pDC316-VEGF165-IRES-SDF-1 and backbone plasmid pBHGlox_E1, 3Cre were transfected into HEK293 cells by liposome and the recombinant adenoviral particles capable of infection were acquired. With the rounds of amplification, the purified adenoviral vector Ad5-VEGF165-IRES-SDF-1 was obtained with a titer of up to 1×10(10) IU/ml. The rat model of middle cerebral artery occlusion (MCAO) was established by intra-luminal suturing. And the viral vectors were transfused into the lateral ventricle by a stereotactic microinjection. The expressions of VEGF165 and SDF-1 in ischemic brain tissue were examined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot., Results: The results of PCR, double enzyme digestion and gene sequencing showed that both the recombinant plasmid and the constructed adenoviral vector were expressed. And the adenoviral vector Ad5-VEGF165-IRES-SDF-1 could mediate a co-expression of VEGF165 and SDF-1 in ischemic cerebral tissue., Conclusion: The recombinant adenoviral vector carrying VEGF165 and SDF-1 are successfully constructed. And Ad5-VEGF165-IRES-SDF-1 may mediate a co-expression of VEGF165 and SDF-1 in ischemic cerebral tissue of rats.