Construction and rescue of infectious cDNA clone of pigeon-origin Newcastle disease virus strain JS/07/04/Pi / 病毒学报

Based on the complete genome sequence of pigeon-origin Newcastle disease virus strain JS/07/04/ Pi(genotype VIb), nine overlapped fragments covering its full-length genome were amplified by RT-PCR. The fragments were connected sequentially and then inserted into the transcription vector TVT7/R resulting in the TVT/071204 which contained the full genome of strain JS/07/04/Pi. The TVT/071204 was co-transfected with three helper plasmids pCI-NP, pCI-P and pCI-L into the BSR cells, and the transfected cells and culture supernatant were inoculated into 9-day-old SPF embryonated eggs 60 h post-transfection. The HA and HI tests were conducted following the death of embryonated eggs. The results showed that the allantoic fluids obtained were HA positive and the HA could be inhibited by anti-NDV serum which indicated that the strain JS/07/04/Pi was rescued successfully. The rescued virus rNDV/071204 showed similar growth kinetics to its parental virus in CEF. The successful recovery of this strain would contribute to the understanding of the host-specificity of pigeon-origin NDV and to the development of the novel vaccines against the NDV infection in pigeons.

Effect of 15-hydroxyeicosatetraenoic acid on calcium ion concentration of cerebral arterial smooth muscle cells in rats / 中华神经医学杂志

Objective To observe the effect of 15-hydroxyeicosatetraenoic acid (15-HETE) on the intracellular calcium ion ([Ca2+]i) concentration of cerebral arterial smooth muscle and discuss the source of ([Ca2+]i) mobilization induced by 15-HETE to reveal the mechanism underlying the vasoconstriction aroused by 15-HETE. Methods First, papain and collagenase were employed to isolate the cerebral artery smooth muscle cells (SMCs) from the rats. The cells were separated into experimental group (treated with 15-HETE) and control group. Confocal laser scanning microscope was used to investigate the ([Ca2+]i) signaling in cultured SMCs. Then, Ca2+ channel blockers and Ca2+ store depletion agent were added to identify the source of Ca2+ transients in SMCs of the 2 groups. Finally, internal carotid artery (ICA) rings were used to observe the effect of non-Ca2+ solution on 15-HETE-induced ICA vasoconstriction on both groups. Results Compared with the control group, 15-HETE treatment group enjoyed a significantly increased level of ([Ca2+]i) in cultured SMCs (P＜0.05). After the addition of Ca2+channel blockers (nifedipine, lanthanum ion) and calcium-free solution, 15-HETE treatment group still enjoyed a significantly increased level of ([Ca2+]i) in cultured SMCs as compared with the control group (P＜0.05), while after the addition of Ca2+ store depletion agent (caffeine), no obvious difference was noted between the 2 groups (P＞0.05). Non-Ca2+ solution had no effect on 15-HETE induced vasoconstriction.Conclusion 15-HETE may activate Ca2+ releasing from intracellular stores to rise. ([Ca2+]i) level in SMCs, which subsequently induce the constriction of cerebral arterial smooth muscle.