[Assessment of the mechanical properties and biocompatibility of a new electrospun polyurethane vascular prosthesis].

OBJECTIVE: To develop a small-caliber vascular grafts and study its morphologies, mechanical properties and biocompatibility. METHODS: The effects of electrospinning conditions on the microstructure and porosity of the resulting scaffolds were investigated for preparation of a small-caliber (4 mm) polyurethane vascular grafts with optimum microstructures and mechanical properties. The mechanical properties and biocompatibility of the prepared grafts were evaluated. RESULTS: The polyurethane vascular grafts showed a three-dimensional reticular structure consisting of nanofibers, with an average porosity of (51.48∓4.47)% and tensile strength of 5.85 ∓ 0.62 MPa. The grafts provided a better long-term support than e-PTFE graft for endothelial cell growth and endothelialization. CONCLUSION: The polyurethane vascular prosthesis possessed favorable microstructures, excellent mechanical properties and good biocompatibility for potential clinical application.

[RANTES expression in venous ulceration of lower limbs].

OBJECTIVE: To investigate the expression of RANTES in venous ulceration. METHODS: From patients with lower limb venous ulceration, patients with non-ulcerous venous insufficiency, and healthy individuals, peripheral blood was collected from the lower limb veins for measurement of RANTES mRNA using RT-PCR. RESULTS: In the ulceration group, the expression of RANTES mRNA was significantly increased as compared with the other two groups (P<0.01). RANTES mRNA expression was also significant higher in the non-ulcerous group than the control group (P<0.01). CONCLUSION: High expression of RANTES mRNA may be one of the important mechanisms of venous ulceration.

[Expression of estrogen receptor, progesterone receptor, and human epithelial growth factor receptor 2 in breast cancer and the significance thereof: analysis of 910 cases].

OBJECTIVE: To investigate the expression of estrogen receptor (ER), progesterone receptor (PR), and human epithelial growth factor receptor 2 (HER2) in breast cancer, and to explore their correlation with the age of patient, and size, clinic stage, and lymph node metastasis of the tumor. METHODS: The data of 910 breast cancer, 89.4% of invasive ductal carcinoma, 1.7% of invasive lobular carcinoma, 44 cases 5% of ductal carcinoma in situ, and 4.9% of other pathologic types, 29.9% being less than 2 cm, 45.6% being 2-5 cm, and 24.5% bigger than 5 cm in size, 54.2% without metastasis in lymph node, 25.5% with metastasis in 1-3 lymph nodes, and 20.3% with metastasis in more than 3 lymph nodes respectively, were analyzed retrospectively. Immunohistochemistry was used to detect the expression of ER, PR, and HER2. RESULTS: The ER negative expression rate was 33.0%, and PR negative expression rate was 27.4%, and HER2 overexpression rate was 20.3%. The possibility of lymph node metastasis decreased along with the increase of age (P < 0.001). Tumor size was negatively correlated with the expression of ER and PR (both P < 0.001), and positively correlated with the expression of HER2 (P < 0.001). There was no significant difference between the situation of lymph node metastasis and the expression of ER, PR and HER2 in primary tumors. CONCLUSION: As good prognostic markers of breast invasive ductal cancer, ER and PR are negatively correlated with the HER2 expression, as a worse prognostic marker. ER/PR positive or HER2 negative tumors are morel likely to be diagnosed at earlier stages.

[Selection of the initial surgery extent for differentiated thyroid cancer without metastasis].

OBJECTIVE: To discuss the selection of the initial surgery extent for differentiated thyroid cancer (DTC) without metastasis. METHODS: The clinical data of 504 cases with DTC, who accepted the surgical treatment from Jan 1995 to Dec 2004, were analyzed and studied. There were 329 cases without metastasis. The operative extents less than total thyroidectomy were performed on 93 cases (92.1%) with stage T(1), 166 cases (88.3%) with stage T(2), 22 cases (91.7%) with stage T(3) and 12 cases (75.0%) with stage T(4). The recurrence situation after the initial surgery was compared between different T-stage groups and between different surgical extents, total and less than total thyroidectomy. RESULTS: The recurrence of DTC was found in 37 cases of the follow-up cases (8.9%), including 29 cases without metastasis in the initial surgery. There was no significant difference in the recurrent rate between T(1) and T(2) groups (P>0.05). The significant difference was found in recurrent rate between T(1) and T(3) or T(4) groups, T(2) and T(3) or T(4) groups (P<0.05). No significant difference in the ratio of the initial surgical extent less than total thyroidectomy was found between stage T(1) and T(2) cases without metastasis (P>0.05). The rate of the recurrent laryngeal nerve injury was 1.2%. The transient hypoparathyroidism happened in 2% of the cases, without the permanent hypoparathyroidism. CONCLUSIONS: The surgical extent less than total thyroidectomy, especially subtotal thyroidectomy, is rational and available to stage T(1) and T(2) cases of DTC without metastasis. It can effectively remove the tumor and avoid postoperative complications. Total thyroidectomy should be performed on stage T(3) and T(4) cases of DTC.

[A random, comparative study on endovenous laser therapy and saphenous veins stripping for the treatment of great saphenous vein incompetence].

OBJECTIVE: To evaluate the therapeutic effects of endovenous laser therapy (EVLT) and saphenous veins stripping in the treatment of great saphenous vein incompetence. METHODS: Eighty cases (80 limbs) with great incompetent saphenous vein were randomly divided into 2 equal groups: EVLT group and stripping group. The patients in the EVLT group underwent EVLT and those in the stripping group underwent upper ligation and stripping of great saphenous vein. The duration of operation, blood losing, complications, pain grade, and hospitalization time were compared. All cases were followed up for 6 months and 12 months using Doppler sonography and air Plethysmography. RESULTS: The blood losing (P < 0.01), hospitalization time (P < 0.05) and pain grade (P < 0.05) in the EVLT group were all significantly less than those in the stripping group, while the operation duration and complication were not significantly different between the two groups (P > 0.05). All patients in both groups got improvements of venous volume (P < 0.05), Venous Filling Index (P < 0.01), and residual Venous Fraction (P < 0.01), yet there were no statistical differences between the two groups (P > 0.05). CONCLUSION: Endovenous laser therapy is a safe, effective, minimal invasive procedure for the patients with great saphenous vein incompetence. Its short-time efficiency is similar to that of the traditional upper ligation and laceration of greater saphenous vein.

[pCKM-mPTH recombinant plasmid therapy for hypoparathyroidism by polycationic liposome-mediated transfection].

OBJECTIVE: To investigate the optimal ratio of polycationic liposome mediated pCKM-mPTH recombinant gene transfer to skeleton cells in the gene therapy of hypoparathyroidism (HPT). METHODS: The protective roles of polycationic liposome to DNA were observed by the DNaseIsensitive test. Liposome-plasmid complex (lipoplexes) with various liposome to plasmid ratio and the naked plasmid were transferred both in vivo and in vitro. The supernatants and serums were collected for measuring parathyroid hormone (PTH) with radioimmunoassay. RESULTS: When the ratio of lipoplexes reached 2:1, there were obviously protective roles to DNA. While it was 3:1, mPTH transgene expressing reached peak which the PTH amount was (16.4 +/- 4.8) pg/10,000 cells/24 h. Furthermore, the amount serum PTH of the HPT model SD rats reached the highest (35.9 pg/ml +/- 2.2 pg/ml) till the concentration of pCKM-mPTH is 20 microg/100 microl with 3:1 ratio of lipoplexes. CONCLUSION: Polycationic liposomes are more effective than naked plasmids for pCKM-mPTH recombinant gene transfer to skeleton cells. The results also indicated that the effect of pCKM-mPTH transferring into muscles might be depended on the optimal ratio and dosage of lipoplexes.