Abscisic acid (ABA) plays an important role in plant growth and developmental processes. Although some ABA signal molecules, such as cADPR, Ca2+, etc., have been reported, there. was no evidence proving the involvemen...Abscisic acid (ABA) plays an important role in plant growth and developmental processes. Although some ABA signal molecules, such as cADPR, Ca2+, etc., have been reported, there. was no evidence proving the involvement of cAMP in A-B-A, signal transduction. In this present study, the constructed gene ( rd29A-GUS) was transformed into Nicotiana tabacum, and calli was induced from the transgenic plant. The suspension cells obtained from the callus grew well and uniformly. Treatment of the suspension cells with ABA led to an increase in GUS activity, indicating that these transgenic suspension cells are useful for the study of ABA signaling. Addition of nicotinamide (cADPR inhibitor) or U-73122 (phospholiphase C inhibitor) could only partially inhibit the increase of GUS activity elicited by ABA. The inhibitory effect of nicotinamide was enhanced by application of K252a (inhibitor of protein kinase). Treatment of the suspension cells with 8-Br-cAMP, a membrane-permeable analogue of cAMP, could partially replace the effect of ABA. Furthermore, intracellular addition of IBMX (phosphodiesterase inhibitor) mimicked die effect of exogenous cAMP on the deduction of expression of rd29A promoter. These results suggested that cAMP was an important messenger in ABA signal transduction in tobacco suspension cell.展开更多
The dynamic changes of tumor necrosis factor (TNF) in the circulating blood and its effects on the severity of Pseudomonas aeruginosa induced septic shock were observed in rabbits. 7×109 and 2×109 P. aerugin...The dynamic changes of tumor necrosis factor (TNF) in the circulating blood and its effects on the severity of Pseudomonas aeruginosa induced septic shock were observed in rabbits. 7×109 and 2×109 P. aeruginosa per ki1ogram body weight were intravenously infused to the rabbits to induce mild and severe septic shock.Particular dynamic characterictics of the changes of the circulating TNF were found during P. aeruginosa septic shock. The increase of TNF level in the circulating blood was closely correlated to the initiation and development of P. aeruginosa shock. It is concluded that TNF plays an important role in the mediation of the pathological manifestations of P. aeruginosa shock.展开更多
文摘Abscisic acid (ABA) plays an important role in plant growth and developmental processes. Although some ABA signal molecules, such as cADPR, Ca2+, etc., have been reported, there. was no evidence proving the involvement of cAMP in A-B-A, signal transduction. In this present study, the constructed gene ( rd29A-GUS) was transformed into Nicotiana tabacum, and calli was induced from the transgenic plant. The suspension cells obtained from the callus grew well and uniformly. Treatment of the suspension cells with ABA led to an increase in GUS activity, indicating that these transgenic suspension cells are useful for the study of ABA signaling. Addition of nicotinamide (cADPR inhibitor) or U-73122 (phospholiphase C inhibitor) could only partially inhibit the increase of GUS activity elicited by ABA. The inhibitory effect of nicotinamide was enhanced by application of K252a (inhibitor of protein kinase). Treatment of the suspension cells with 8-Br-cAMP, a membrane-permeable analogue of cAMP, could partially replace the effect of ABA. Furthermore, intracellular addition of IBMX (phosphodiesterase inhibitor) mimicked die effect of exogenous cAMP on the deduction of expression of rd29A promoter. These results suggested that cAMP was an important messenger in ABA signal transduction in tobacco suspension cell.
文摘The dynamic changes of tumor necrosis factor (TNF) in the circulating blood and its effects on the severity of Pseudomonas aeruginosa induced septic shock were observed in rabbits. 7×109 and 2×109 P. aeruginosa per ki1ogram body weight were intravenously infused to the rabbits to induce mild and severe septic shock.Particular dynamic characterictics of the changes of the circulating TNF were found during P. aeruginosa septic shock. The increase of TNF level in the circulating blood was closely correlated to the initiation and development of P. aeruginosa shock. It is concluded that TNF plays an important role in the mediation of the pathological manifestations of P. aeruginosa shock.
