The study of multipoint blank holder force（BHF） control is carried out for hydroforming a complicated shape motorcycle fuel tank. By finite element method （FEM） simulation, the configuration of multipoint blank ho...The study of multipoint blank holder force（BHF） control is carried out for hydroforming a complicated shape motorcycle fuel tank. By finite element method （FEM） simulation, the configuration of multipoint blank holder cylinders and the setting of local BHF are optimized, and the influences of the multipoint BHF on the hydromechanical deep drawing and conventional hydroforming processes are studied. The desired fluid pressure and whole BHF are predicted for hydromechanical deep drawing process. Finally, simulation results are testified by forming experiment, and they are in agreement very well.展开更多
Restin,a member of melanoma-associated antigen superfamily gene,was first cloned from differentiated leukemia cell induced by all trans-retinoic acid,and was able to inhibit cell proliferation,but the molecular mechan...Restin,a member of melanoma-associated antigen superfamily gene,was first cloned from differentiated leukemia cell induced by all trans-retinoic acid,and was able to inhibit cell proliferation,but the molecular mechanism was not clear.Since Restin was localized in cell nucleus,and its homolog member,Necdin(neuronal growth suppressor factor),could interact with transcription factors p53 and E2F1,we proposed that Restin might also function as Necdin through interacting with some transcription factors.In this study,transcription factors p53,AP1,ATFs and E2Fs were cloned and used in the mammalian two-hybrid system to identify their in-teraction with Restin.The results showed that only ATF3 had a strong interaction with Restin.It is interesting to know that ATF3 was an important transcription factor for G1 cell cycle initiation in physiological stress response.It was possible that the inhibition of cell proliferation by Restin might be related with the inhibition of ATF3 activity.展开更多
Restin, belonging to the melanoma-associated antigen superfamily, was firstly cloned from the differentiated HL-60 cells when induced by all-trans retinoic acid ( ATRA ) in our lab. Our previous results showed that re...Restin, belonging to the melanoma-associated antigen superfamily, was firstly cloned from the differentiated HL-60 cells when induced by all-trans retinoic acid ( ATRA ) in our lab. Our previous results showed that restin might be correlated to cell cycle arrest. Due to the importance of p53 in the regulation of cell growth and the relationship between p53 and ATRA, we tried to test the relationship between p53 and restin. Firstly, transfection results showed that p53 was able to upregulate the expression of restin at the transcriptional level when p53 was transfected into eukaryotic cells. Secondly, the bioinformatics analysis revealed that the upstream sequence (about 2 kb) from the first ATG of the ORF of restin gene contained a p53 binding site. In order to confirm that p53 was involved in the transcriptional regulation of restin, we cloned the upstream sequence of restin and constructed the promoter luciferase reporter system. From the luciferase activity, we demonstrated that the promoter of restin gene could be induced by ATRA. Then, another two luciferase reporter plasmids driven by the reporter of restin with no (RP?p53-luc) or mutant (mRP-luc) p53 binding site were constructed to see the regulation of restin by p53. Results showed that the transcriptional upregulation of restin gene was not due to the putative p53 binding site on the upstream of restin gene. We proposed that p53 upregulated restin transcription through an indirect way rather than direct interaction with the cis-activating element of the restin promoter.展开更多
基金This project is supported by Doctoral Fundation of China(No.20010487002) and Municipal Key Technology R&D Program of Guangzhou, China(No, 2002Z3-0211).
文摘The study of multipoint blank holder force（BHF） control is carried out for hydroforming a complicated shape motorcycle fuel tank. By finite element method （FEM） simulation, the configuration of multipoint blank holder cylinders and the setting of local BHF are optimized, and the influences of the multipoint BHF on the hydromechanical deep drawing and conventional hydroforming processes are studied. The desired fluid pressure and whole BHF are predicted for hydromechanical deep drawing process. Finally, simulation results are testified by forming experiment, and they are in agreement very well.
文摘Restin,a member of melanoma-associated antigen superfamily gene,was first cloned from differentiated leukemia cell induced by all trans-retinoic acid,and was able to inhibit cell proliferation,but the molecular mechanism was not clear.Since Restin was localized in cell nucleus,and its homolog member,Necdin(neuronal growth suppressor factor),could interact with transcription factors p53 and E2F1,we proposed that Restin might also function as Necdin through interacting with some transcription factors.In this study,transcription factors p53,AP1,ATFs and E2Fs were cloned and used in the mammalian two-hybrid system to identify their in-teraction with Restin.The results showed that only ATF3 had a strong interaction with Restin.It is interesting to know that ATF3 was an important transcription factor for G1 cell cycle initiation in physiological stress response.It was possible that the inhibition of cell proliferation by Restin might be related with the inhibition of ATF3 activity.
基金the National Natural Science Foundation of China (Grant Nos. 30271457 and 30470874)
文摘Restin, belonging to the melanoma-associated antigen superfamily, was firstly cloned from the differentiated HL-60 cells when induced by all-trans retinoic acid ( ATRA ) in our lab. Our previous results showed that restin might be correlated to cell cycle arrest. Due to the importance of p53 in the regulation of cell growth and the relationship between p53 and ATRA, we tried to test the relationship between p53 and restin. Firstly, transfection results showed that p53 was able to upregulate the expression of restin at the transcriptional level when p53 was transfected into eukaryotic cells. Secondly, the bioinformatics analysis revealed that the upstream sequence (about 2 kb) from the first ATG of the ORF of restin gene contained a p53 binding site. In order to confirm that p53 was involved in the transcriptional regulation of restin, we cloned the upstream sequence of restin and constructed the promoter luciferase reporter system. From the luciferase activity, we demonstrated that the promoter of restin gene could be induced by ATRA. Then, another two luciferase reporter plasmids driven by the reporter of restin with no (RP?p53-luc) or mutant (mRP-luc) p53 binding site were constructed to see the regulation of restin by p53. Results showed that the transcriptional upregulation of restin gene was not due to the putative p53 binding site on the upstream of restin gene. We proposed that p53 upregulated restin transcription through an indirect way rather than direct interaction with the cis-activating element of the restin promoter.
