1.The relationship between vascular endothelial growth factor C and recurrence following curative resection of pancreatic cancer
Weiyi WANG ; Wenhao TANG ; Zurong YUAN ; Jianxiong TANG ; Wei WANG ; Yanyuan TU ; Hao DING
Chinese Journal of Hepatobiliary Surgery 2011;17(6):479-483
Objective To investigate the prognostic value of vascular endothelial growth factor C (VEGF-C) and clinicopathologic indexes in predicting recurrence following curative resection of pancreatic cancer. Methods The expressions of VEGF-C of 47 patients who underwent curative resection for curative pancreatic cancer resection were detected by Envision immunohistochemical methods. The effects of VEGF-C and clinicopathologic indexes on recurrence were assessed by the Kaplan-Meier and Cox proportional hazards model. Results The positive rates of VEGF-C were 61. 7% in = 29) and 14. 9%(n = 7), respectively, in pancreatic cancer and normal pancreatic tissues. The positive expression of VEGF-C in pancreatic carcinoma was obviously higher than the normal pancreatic tissues (P = 0. 018). The median disease-free survival time was 11. 9 months, the average disease-free survival time was 18. 4 + 2. 4 months, and the cumulative 1-year, 2-year and 3-year actuarial recurrence free survival rates were 46. 8%, 23. 4%, 14. 4%, respectively. There was a significant correlation between the VEGF-C expression and lymph node metastasis in pancreatic cancer (P = 0. 036). On Kaplan-Meier analysis, VEGF-C (P = 0. 020), tumor diameter (P = 0. 013), age (P = 0. 057) and adjuvant chemotherapy (P=0. 017) were associated with disease-free survival time. Multivariate analysis showed VEGF-C (P = 0. 009), tumor diameter (P = 0. 010) and adjuvant chemotherapy (P = 0. 017)were independent prognostic factors of disease-free survival after surgery for pancreatic cancer.Conclusion The expression of VEGF-C was higher in pancreatic cancer, and VEGF-C was correlated with lymph node metastasis. VEGF-C was the biomarker that independently predicted disease-free survival after surgery for pancreatic cancer.
2.Biomechanical study of human dura and its substitutes.
Liangfu ZHOU ; Donglei SONG ; Zurong DING
Chinese Medical Journal 2002;115(11):1657-1659
OBJECTIVETo investigate the biomechanical characters of human dura and its substitutes and to establish guidelines for selection of optimal repair materials for reconstruction of skull base defects.
METHODSA measurement of creep properties of human dura and its substitutes were conducted using biomechanical tests. The dynamic changes of biomechanical properties of canine dura obtained from skull base defects were observed as well.
RESULTSThe creep properties of human dura presented a linear-relationship between initial strain and stress, and the creep strain increased slowly with time. The creep compliance formula for human dura and its substitutes was as follows: J (t) = J(0) + Kf (t). The initial compliance of canine dura in skull base defects was reduced by 35%, 46% and 50%, respectively 1, 3 and 6 months after surgery.
CONCLUSIONThe optimal material for the repair of skull base defects can be estimated using creep compliance analysis. The less the compliance, the better the property of anti-protrusion. Fresh human dura is the least compliant and then in increasing order are lyophilized human dura, fresh human pericranium, Terylene and silicon membranes. The pattern of biomechanical characteristics of the dura mater at skull base defects shows that the strain ability of the dura mater decreases distinctly for 1 - 3 months and then remains almost unchanged for 3 - 6 months after surgery.
Animals ; Biomechanical Phenomena ; Dogs ; Dura Mater ; physiology ; Humans ; Skull Base ; surgery