As the meeting point of signaling pathways actived by growth factors and amino acids,especially leucine,in tumor cells,mammalian target of rapamycin (mTOR) plays an important role as a center factor of regulation.Recently,it was acknowledged gradually that feedback activation mechanisms of mTOR can influence the efficiency of rapamycin and its analogs in antitumor therapy.Thus,the study about feedback mechanism of mTOR and the combination therapy of mTOR inhibitors and specificd pathway inhibitors has become the hot area in cancer therapy and prevention.

Objective To detect the apoptosis of femoral head cartilage cells and to observe the expression of apoptosis-related proteins in the tissues of the femoral head,as well as to explore the main pathway for regulating the apoptosis in steroid induced by juvenile rabbit models with avascular necrosis of femoral head.Methods The models with avascular necrosis of the femoral head and the control group model were made in New Zealand infancy albino rabbits induced by glucocorticoid(GC).The immunohistochemical method was used to detect the expressions of Caspase3,Caspase-8,apoptosis protease activating factor-1 (apaf-1),calpain-1 in the femoral heads.Results 1.The integrated optical density(IOD) values of Caspase-3 in GC-induced subgroup,the subgroup that was not induced by GC and control group were 25 142.72 ± 21 528.48,2 069.63 ± 1 096.96 and 301.80 ± 99.66,respectively.The IOD values of Caspase-8 in GC-induced subgroup,the subgroup respectively and the control group were 24 942.63 ± 18 942.99,2 016.31 ± 1 518.70,236.85 ±97.94,respectively.The IOD values of apaf-1 in GC-induced subgroup,the subgroup that was not induced by GC and the control group were 8 5 14.23 ± 6 384.20,1 118.49 ± 1 360.59,95.13 ± 38.05,respectively.The IOD values of calpain-1 in GC-induccd subgroup,the subgroup that was not induced by GC and control group were 9 636.71 ± 9 123.81,1 881.10 ± 3 277.86,126.71 ± 47.35,respectively.The IOD value differences of the Caspase-3 between GC-induced subgroup and the subgroup that was not induced by GC,the control group were extremely significant (H =l 1.470,23.996,P ＜ 0.01).The IOD value differences of the Caspase-8,apaf-1,calpain-1 between GC-induced subgroup and the control group were extremely significant (H =22.178,22.808,13.553,P ＜ 0.01).2.The linear regression analysis results showed that under the joint action of Caspase-8,apaf-1,calpain-1,only the Caspase-8 could significantly predict Caspase-3,and its regression equation regression got significant effect and could explain 40.3％ of the variance;while the regression effects of the apaf-1 and calpain-1 to Caspase-3 were not significant.Conclusion Death receptor pathway might play a major regulation role in the apoptotic process of avascular necrosis.

Objective To compare the effectiveness of expandable intramedullary nail(EIMN) versus locked compression plate (LCP) in the treatment of humeral shaft fractures of AO types A and B.Methods The clinical data were retrospectively analyzed and compared of the 44 humeral shaft fractures which had been treated between May 2012 and February 2016.There were 26 men and 18 women,from 23 to 66 years of age (average,41.5 years).By AO classification,22 cases were type 12-A and 22 type 12-B.EINM was used in 22 patients with an average age of 41.3 ± 1 1.7 years and LCP in 22 ones with an average age of 41.6 ± 10.3 years.The 2 groups were compared in terms of intraoperative blood loss,operative time,hospital stay,union time,union rate,Constant and Mayo scores at the final follow-ups,and complications as well.Results The 2 groups were compatible without significant differences in the preoperative demographic data (P ＞ 0.05).All the 44 patients were followed up for 10 to 18 months (average,12 months).The intraoperative blood loss (76.4 ± 18.66 mL),operative time (69.1 ± 13.2 min),incision length (5.8 ± 1.5 cm) and union time (13.2 ± 8.4 w) in the EIMN group were significantly better than those in the LCP group (138.6 ± 39.4 mL,96.4 ± 14.2 min,8.5 ± 1.4 cm and 18.4 ± 6.6 w,respectively) (P ＜ 0.05).There was also a significant difference between the 2 groups in the total complication rate[18.2％ (4/22) versus 50.0％ (11/22)] (P ＜0.05).No deep infection or should pain was observed in either group.Conclusions Inthe treatment of humeral shaft fractures of AO types 42-A and 42-B,compared with LCP,EIMN may have advantages of less intraoperative blood loss,operative time,union time and complications.The 2 methods are similar in hospital stay and final functional recovery of the should joint.

Alzheimer's disease（AD） is an irreversible neurodegenerative disease with clinical manifestations such as memory impairment， aphasia， impaired visuospatial skills， executive function impairment， and personality changes. AD has brought a heavy burden to the family and society due to its unrevealed pathogenesis and the lack of therapeutic approaches. Saponins， a group of oligoglycosides whose aglycones are triterpenes or spirosteroids， are divided into triterpene saponins and steroidal saponins， which have a variety of biological activities. At present， there is no systematic review on the anti-AD effect of saponins. According to the literature published in recent years， the authors summarized the studies of saponins in improving AD based on animal experiments. The results indicated that saponins enhanced learning ability and improved cognitive impairment by inhibiting amyloid β-protein （Aβ） cascade activity， suppressing microtubule-associated protein （tau） hyperphosphorylation， inhibiting neuronal oxidative stress， inhibiting inflammatory factors， regulating apoptosis， inhibiting cholinergic neuronal degeneration， promoting mitochondrial autophagy， regulating intestinal flora， and enhancing energy metabolism， which in turn improved the pathological state of AD animal models. The therapeutic effects of different saponins on AD are different. The present study discussed the effect of different aglycones and sugar chains on the anti-AD activity based on saponins and anti-AD effect to provide new ideas and a theoretical basis for the development and utilization of saponins.