Gambogic acid induces apoptosis of Jurkat cell through the MAPK signal pathway / 中国实验血液学杂志

The aim of this study was to investigate the apoptosis-inducing effect of gambogic acid (GA) on Jurkat cells and its underlying signaling pathway. Apoptosis induced by GA and some inhibitors was assayed by Annexin V/PI doubling staining. The levels of caspase 3, caspase 8 and caspase 9 activated in living Jurkat cells were measured by flow cytometry. The expressions of caspase 3, caspase 9, p-JNK and P38 were detected by Western blot. The results showed that GA induced apoptosis of Jurkat cells in a dose-dependent manner. The positive cell number of activated caspase 3, caspase 8, caspase 9 and the levels of activated caspase 3, caspase 9, p-JNK, P38 increased after Jurkat cells were treated with GA. ROS, CaMKII, caspase 3, caspase 9, MAPKK, JNK1/2 and P38 inhibitors had some significant effect on GA-induced apoptosis. ROS, CaMKII, MAPKK, JNK1/2 and P38 inhibitors decreased the levels of activated caspase 3, caspase 9 by GA.ROS, CaMKII, MAPKK, JNK1/2 inhibitors decreased the levels of p-JNK by GA. ROS, CaMKII, MAPKK, P38 inhibitors decreased the levels of P38 by GA. It is concluded that GA induced apoptosis of Jurkat cells by activated caspases through activating of ROS-CaMKII-MAPKK-JNK/P38 pathway.

Experimental study of preparing curved root canals with different instrument / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To compare the shaping ability and the influence on apical foramen among hand ProTaper, stainless steel K-files and rotary ProTaper in preparing different curved root canal.</p><p><b>METHODS</b>Forty simulated resin root canal blocks were randomly divided into four groups and prepared by hand ProTaper, stainless steel K-file and rotary ProTaper, respectively. Of them, 12 blocks in group A, B, C consist of six 200 curved root canals and six 30 degrees curved root canals each group. The curvature of the other 4 blocks in group D was less than 5 degrees. Taking photos of the models to the root canal orthotopically and apical foramen using digital camera before and after instrumentation. Finally, the transportation of root canal and the size of apical foramen were analyzed using special image software Auto-CAD.</p><p><b>RESULTS</b>The transportation of center in group B was the highest than that in group A and group C (P<0.05). In some portions of root canal, the transportation of center in group C was higher than that in group A. The size of the apical foramen in group B was significantly bigger than the other groups and the size of the apical foramen in 30 degrees root canal was significantly bigger than that in 20 degrees root canal after instrumentation (P<0.05). There was no significantly different between group A and group C, though the size of apical foramen in group C was bigger than that in group A at the same curvature, and that in 30 degrees root canal was bigger than in 20 degrees root canal (P>0.05).</p><p><b>CONCLUSION</b>Both of the two instruments engender root canal transportation, and curvature is the main reason of transportation. Comparing with stainless steel K-files, NiTi files can maintain the shape of the root canal and apical foramen well.</p>