The present study investigates the molecular details of how arsenic trioxide inhibits preadipocyte differentiation and examines the role of Akt/PKB in regulation of differentiation and apoptosis. Continual exposure of...The present study investigates the molecular details of how arsenic trioxide inhibits preadipocyte differentiation and examines the role of Akt/PKB in regulation of differentiation and apoptosis. Continual exposure of arsenic trioxide, at the clinic achievable dosage that does not induce apoptosis, suppressed 3T3-L1 cell differentiation into fat cells by inhibiting the expression of PPARγ and C/EBPα and disrupting the interaction between PPARγ and RXRα, which determines the programming of the adipogenic genes. Interestingly, if we treated the cells for 12 or 24 h and then withdrew arsenic trioxide, the cells were able to differentiate to the comparable levels of untreated cells as assayed by the activity of GAPDH, the biochemical marker of preadipocyte differentiation. Long term treatment blocked the differentiation and the activity of GAPDH could not recover to the comparable levels of untreated cells. Continual exposure of arsenic trioxide caused accumulation in G2/M phase and the accumulation of p21. We found that arsenic trioxide induced the expression and the phosphorylation of Akt/PKB and it inhibited the interaction between Akt/PKB and PPARγ . Akt/PKB inhibitor appears to block the arsenic trioxide suppression of differentiation. Our results suggested that Akt/PKB may play a role in suppression of apoptosis and negatively regulate preadipocyte differentiation.展开更多
Despite significant advances in monoclonal antibodies (Mabs) technology over the last two decades, technology to develop natural occurring and fully human therapeutic Mabs from patients without known antigens is still...Despite significant advances in monoclonal antibodies (Mabs) technology over the last two decades, technology to develop natural occurring and fully human therapeutic Mabs from patients without known antigens is still in its infancy. Human myeloma cell lines have been very difficult to derive. Attempts in numerous laboratories to use those cells for the production of human monoclonal antibodies have failed despite early reports. A human myeloma cell line that is suitable for the generation of human monoclonal antibodies (Proceedings of the National Academy of Sciences USA 98:1799-1804) was developed by Dr. Karpas. Since 1975 researchers across the world have been trying to replicate the process with human cells.展开更多
Following hydrothermal synthesis process, MCM-41 was synthesized by using cetyltriethylammonium bromide as templating agent. The experimental results showed that MCM-41 with pore diameter in the range of 4-7 nm can be...Following hydrothermal synthesis process, MCM-41 was synthesized by using cetyltriethylammonium bromide as templating agent. The experimental results showed that MCM-41 with pore diameter in the range of 4-7 nm can be obtained by adjusting nsurf/nsi. It was proved that cetyltriethylammonium bromide is an effective templating agent for increasing pore diameter of molecular sieve MCM-41.展开更多
Purpose:According to Quigley's hypothesis the dense of connective tissue is the least and the pores of the lamina cribrosa are the largest at the superior and infe-rior poles of the lamina cribrosa,therefore they ...Purpose:According to Quigley's hypothesis the dense of connective tissue is the least and the pores of the lamina cribrosa are the largest at the superior and infe-rior poles of the lamina cribrosa,therefore they are the most vulnerable location to be involved in the characteristic glaucomatous optic nerve damage,To get clin-ical evidence for the hypltheses,the reversal of optic cup in adults glaucoma after reduction of intraocular pressure(IOP)was examined.Methods:The stereoscopic flicker comparison on with computerized image sys-tem was used to monitor the optic cup's changing,2 serial superposed stereo pairs were displayed alternatively and rapidly and the changing parts appeared moving Under the stereoscopic observation ,hthe changes of 3-dimention optic cup could be seen and the false positive phenomena caused by photographic angle variation,vascular pulsation could be differentiated from the characteristic change of the cup.Stereo fundus photographs were taken from 31eyes with hy-pertension glaucoma before and after treatment of reduction of IOPs which was either diamox administration or trabeculectomy.Results:the result showed that the reversal of optic cups after reduction of IOPs were mostly asymmetrical,especially at the inferior and/or superior poles.By multiple stepwise regression.it is known that the amount of the change is only correlated with the initial elevated IOP.Conclusions:The study indicated that it was the distortion and deformity of the lamina cribrosa leading to shearing stress that results in glaucomatous character-istic damage in structure and function.The individul tolerance of the lamina cribrosa to the high intraocular pressure and the locations of indivdual vulnerable at he optic nerve head are various.Eye Science1995;11:155-160.展开更多
Traffic information processing is very complicated because of dynamic, cooperative and distributed features. This paper describes the prototype system version 2.0 of Urban Traffic Information Service Application Grid ...Traffic information processing is very complicated because of dynamic, cooperative and distributed features. This paper describes the prototype system version 2.0 of Urban Traffic Information Service Application Grid (UTISAG), which is based on the previous version. In this version, a new architecture and more enhanced services are introduced, The. remarkable characteristic of the new system is providing dynamic information services for travelers by grid technology. Therefore, the key research includes integrating large multi-source traffic data, forecasting route status, simulating regional traffic flow parallelly, and implementing optimum dynamic travel scheme based on massive GPS data.展开更多
基金This work is supported by grants from National Nature Science Foundation of China(No.30000083)Quan.CHEN's laboratory was supported by grants“Knowledge Innovation Key Project"(kscx2-sw-2010)of Chinese Academy of Sciences+1 种基金the National Basic Research Program of China(973 program project,No.2002CB5 13 100)National Fund for Outstanding Young Scholars from NSFC(30325013)awarded to Quan CHEN.
文摘The present study investigates the molecular details of how arsenic trioxide inhibits preadipocyte differentiation and examines the role of Akt/PKB in regulation of differentiation and apoptosis. Continual exposure of arsenic trioxide, at the clinic achievable dosage that does not induce apoptosis, suppressed 3T3-L1 cell differentiation into fat cells by inhibiting the expression of PPARγ and C/EBPα and disrupting the interaction between PPARγ and RXRα, which determines the programming of the adipogenic genes. Interestingly, if we treated the cells for 12 or 24 h and then withdrew arsenic trioxide, the cells were able to differentiate to the comparable levels of untreated cells as assayed by the activity of GAPDH, the biochemical marker of preadipocyte differentiation. Long term treatment blocked the differentiation and the activity of GAPDH could not recover to the comparable levels of untreated cells. Continual exposure of arsenic trioxide caused accumulation in G2/M phase and the accumulation of p21. We found that arsenic trioxide induced the expression and the phosphorylation of Akt/PKB and it inhibited the interaction between Akt/PKB and PPARγ . Akt/PKB inhibitor appears to block the arsenic trioxide suppression of differentiation. Our results suggested that Akt/PKB may play a role in suppression of apoptosis and negatively regulate preadipocyte differentiation.
文摘Despite significant advances in monoclonal antibodies (Mabs) technology over the last two decades, technology to develop natural occurring and fully human therapeutic Mabs from patients without known antigens is still in its infancy. Human myeloma cell lines have been very difficult to derive. Attempts in numerous laboratories to use those cells for the production of human monoclonal antibodies have failed despite early reports. A human myeloma cell line that is suitable for the generation of human monoclonal antibodies (Proceedings of the National Academy of Sciences USA 98:1799-1804) was developed by Dr. Karpas. Since 1975 researchers across the world have been trying to replicate the process with human cells.
文摘Following hydrothermal synthesis process, MCM-41 was synthesized by using cetyltriethylammonium bromide as templating agent. The experimental results showed that MCM-41 with pore diameter in the range of 4-7 nm can be obtained by adjusting nsurf/nsi. It was proved that cetyltriethylammonium bromide is an effective templating agent for increasing pore diameter of molecular sieve MCM-41.
文摘Purpose:According to Quigley's hypothesis the dense of connective tissue is the least and the pores of the lamina cribrosa are the largest at the superior and infe-rior poles of the lamina cribrosa,therefore they are the most vulnerable location to be involved in the characteristic glaucomatous optic nerve damage,To get clin-ical evidence for the hypltheses,the reversal of optic cup in adults glaucoma after reduction of intraocular pressure(IOP)was examined.Methods:The stereoscopic flicker comparison on with computerized image sys-tem was used to monitor the optic cup's changing,2 serial superposed stereo pairs were displayed alternatively and rapidly and the changing parts appeared moving Under the stereoscopic observation ,hthe changes of 3-dimention optic cup could be seen and the false positive phenomena caused by photographic angle variation,vascular pulsation could be differentiated from the characteristic change of the cup.Stereo fundus photographs were taken from 31eyes with hy-pertension glaucoma before and after treatment of reduction of IOPs which was either diamox administration or trabeculectomy.Results:the result showed that the reversal of optic cups after reduction of IOPs were mostly asymmetrical,especially at the inferior and/or superior poles.By multiple stepwise regression.it is known that the amount of the change is only correlated with the initial elevated IOP.Conclusions:The study indicated that it was the distortion and deformity of the lamina cribrosa leading to shearing stress that results in glaucomatous character-istic damage in structure and function.The individul tolerance of the lamina cribrosa to the high intraocular pressure and the locations of indivdual vulnerable at he optic nerve head are various.Eye Science1995;11:155-160.
文摘Traffic information processing is very complicated because of dynamic, cooperative and distributed features. This paper describes the prototype system version 2.0 of Urban Traffic Information Service Application Grid (UTISAG), which is based on the previous version. In this version, a new architecture and more enhanced services are introduced, The. remarkable characteristic of the new system is providing dynamic information services for travelers by grid technology. Therefore, the key research includes integrating large multi-source traffic data, forecasting route status, simulating regional traffic flow parallelly, and implementing optimum dynamic travel scheme based on massive GPS data.