Influence from deformation history of NiTi shape-memory-alloy arch-wires on orthodontic force / 医用生物力学

Objective To evaluate the influence from deformation history of arch-wires on its orthodontic force. MethodsA finite element model including brackets and arch-wires in free status was built, and the position of brackets under clinical condition was obtained through laser scanning on the plaster dental model. Based on the finite element method, the brackets were moved to the clinical position through two different movement pathways, using a thermal-mechanical shape-memory-alloy model of arch-wires. The orthodontic force obtained from the two pathways were then compared and analyzed. Results The relative differences in the orthodontic force obtained from the two pathways were significant, with a range from 0.3 to 8.0. The influence of deformation pathway on the orthodontic force was reduced if the arch-wire was first overloaded and then unloaded to the clinical condition，but reduction of the orthodontic force varied at different positions of arch-wires, and the relative differences might increase at certain positions. Conclusions The deformation history of arch-wires has some direct relation with the orthodontic force produced on the NiTi shape-memory-alloy, and the evaluation on the orthodontic force should trace its deformation history.

Effect of 5-fluorouracil aerosol on the growth of human gastric cancer cell line MKN-45 in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the effect of simulated intraperitoneal 5-fluorouracil (5-Fu) aerosol chemotherapy (AIPC) on the proliferation, apoptosis, and cell cycle of human gastric cancer cell line MKN-45 in vitro.</p><p><b>METHODS</b>The gastric cancer cells MKN-45 were treated with 5-Fu aerosol for 30 min under the pressure of 8 mmHg, and those treated with normal saline (NS) aerosol served as the control. The cell proliferation after the treatment was detected by MTT assay, and flow cytometry and FITC Annexin V/PI kit were used to detect the cell apoptosis and changes in the cell cycle.</p><p><b>RESULTS</b>MTT assay showed a significantly greater inhibition rate of the cell proliferation in 5-Fu aerosol group than in NS group [(31.13∓3.51)% vs (4.65∓1.99)%, P<0.001]. FCM analysis also showed a significantly higher cell apoptotic rate in 5-Fu aerosol group than in NS group [(12.00∓0.92)% vs (2.65∓0.52)%, P<0.001]. Compared with saline treatment, treatment with 5-Fu aerosol resulted in a greater proportion of G1 phase cells [(51.83∓1.95)% vs (36.41∓2.33)%, P<0.001] with a lowered proportion of S phase cells [(16.72∓2.36)% vs (45.20∓3.27)%, P<0.001].</p><p><b>CONCLUSION</b>Simulated 5-Fu AIPC can inhibit the proliferation, induce cell apoptosis and cause cell cycle arrest at G1 phase in gastric cancer cells.</p>

Experience of surgical resection of Bismuth-Corlette type I and II hilar cholangiocarcinoma / 中华外科杂志

<p><b>OBJECTIVE</b>To report the experience of surgical resection of Bismuth-Corlette type I and II hilar cholangiocarcinoma.</p><p><b>METHODS</b>From January 1998 and January 2008, 52 cases of Bismuth-Corlette type I and II hilar cholangiocarcinoma were operated on. The clinical data and long-term outcome of the patients was retrospectively analyzed.</p><p><b>RESULTS</b>Of the 52 cases, 44 cases (84.6%) received operation, 28 patients underwent radical resection (63.6%) and 16 patients (36.4%) underwent palliative resection.Seven patients were resected on caudate lobe and other section and lobe of the liver; among them, 2 patients received combined portal vein resection and 4 underwent combined hepatic artery resection respectively. Eleven cases developed postoperative complications and another one died in hospital. The median survival was 33.2 months in radical resection group, and 1-, 3-, 5-year survival rate was 82.6%, 47.8%, 34.7%, respectively, which was significant greater than those in the palliative resection group (41.6%, 16.6%, 8.3%, respectively) (P < 0.05). The median survival was 16.7 months in the palliative resection group.</p><p><b>CONCLUSIONS</b>The radical resection is still the best treatment for Bismuth-Corlette type I and II hilar cholangiocarcinoma. Intraoperative pathology for resection margin, and combined liver resection, portal vein resection and hepatic artery resection can help improve the radical resection rate.</p>

Clinical application of perioperative continuous hyperthermic peritoneal perfusion chemotherapy for gastric cancer / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the clinical effect of intraoperative and early postoperative continuous hyperthermic pertioneal perfusion chemotherapy (CHPPC) for gastric cancer.</p><p><b>METHODS</b>Eight-five patients with gastric cancer were randomized into therapeutic group with perioperative CHPPC combined with intravenous chemotherapy (n=44) and control group with intravenous chemotherapy only (n=41). The postoperative complications, adverse effects, local recurrence rates, distant metastasis rates, and 1- and 3-year survival rates were compared between two groups.</p><p><b>RESULTS</b>No significant differences were found in the postoperative complications and adverse effects between the two groups. The recurrence rate and distant metastasis rates in the therapeutic group were significantly lower than those in the control group (20.45% vs 43.90%, and 15.90% vs 39.02%, P<0.05). The 1- and 3-year survival rates in the therapeutic group were significantly higher than those in the control group (90.90% vs 78.05%, and 59.09% vs 34.15%, P<0.05).</p><p><b>CONCLUSION</b>Perioperative CHPPC for gastric cancer is safe and feasible, and can reduce the recurrence rate, distant metastasis rate and improve the survival for gastric cancer patient after operation.</p>