Proliferative capacity of venous ulcer wound fibroblasts in the presence of platelet-derived growth factor.

Growth factors have been demonstrated to increase the proliferation of wound fibroblasts. Platelet-derived growth factor (PDGF) is a potent cell mitogen. However, the role of PDGF in chronic venous ulcers is inconclusive. This study investigated whether PDGF stimulates venous ulcer fibroblasts to proliferate. Fibroblasts (fb) were isolated from 8 venous ulcers wounds (w-fb) and normal skin (n-fb) of the ipsilateral thigh via punch biopsies. Fibroblasts were plated at 1,500 cells/dish in Dulbecco's Modified Eagle Medium + 10% calf serum (CM) and treated with/without PDGF-alphabeta (10 ng/mL) for 15 days. Growth rates were calculated. Western blotting and immunocytochemistry staining determined basal levels for PDGF-alpha and -beta receptors, respectively. Growth rates were significantly lower in w-fb than in n-fb (1,579 +/-546 vs 13,782 +/-5,882 cells/day, p=0.019). PDGF-alphabeta treatment caused n-fb to increase their proliferative capacity relative to complete media (20,393 +/-6,572 vs 13,782 +/-5,882 cells/day, p=0.005). However, PDGF-alphabeta had no significant effect on w-fb proliferation over CM (1,030 +/-264 and 1,579 +/-546 cells/day, p=0.15). In the presence of PDGF-alphabeta, w-fb had a significantly attenuated growth rate over n-fb (1,030 +/-264 vs 20,393 +/-6,572 cells/day, p=0.019). Western blot and immunocytochemistry analysis revealed diminished basal levels of PDGF-alpha and -beta receptors, respectively, in ulcer fibroblasts. Venous ulcer fibroblasts had decreased proliferation. PDGF-alphabeta had no effect on the growth rate of venous ulcer fibroblasts. In venous ulcers, decreased basal levels of fibroblast PDGF-alpha and -beta receptors may explain reduced proliferation. Further clinical studies are needed to elucidate the role growth factors may play in venous ulcers.

Bovine pericardium vs dacron for patch angioplasty after carotid endarterectomy: a prospective randomized study.

HYPOTHESIS: Bovine pericardium (BP) demonstrates improved intraoperative hemostasis and equivalent perioperative morbidity compared with Dacron when used as patch material for angioplasty following carotid endarterectomy. OBJECTIVE: To prospectively compare BP and Dacron patch angioplasty after carotid endarterectomy in a randomized fashion. METHODS: Ninety-five consecutive primary carotid endarterectomies were performed in a prospective randomized fashion in 92 patients. Fifty-one procedures were performed using BP and 44 using Dacron. Intraoperative suture line bleeding was subjectively evaluated by observing bleeding at 3 and 4 minutes following carotid cross-clamp removal and then objectively weighing the sponge used to tamponade bleeding during these time intervals. Perioperative morbidity, including cervical wound hematoma, transient ischemic attack, and stroke, and perioperative mortality were recorded. Statistical analysis was performed using paired t tests, chi(2) analysis, Fisher exact test, or multiple linear regression as appropriate. RESULTS: Suture line bleeding at 3 minutes was present in 7 (14%) of 51 patients in the BP group and 24 (55%) of 44 patients in the Dacron group (P<.001). Suture line bleeding evaluated at 4 minutes was present in 2 (4%) of 51 patients in the BP group and 13 (30%) of 44 patients in the Dacron group (P =.001). Net +/- SEM sponge weight (total intraoperative suture line bleeding) was 6.25 +/- 0.55 g in the BP group and 16.34 +/- 1.85 g in the Dacron group (P<.001). Total suture line bleeding was significantly affected by activated clotting time; however, multivariate analysis demonstrated that bleeding was significantly less with BP (P<.001) even after adjusting for differences in activated clotting time. CONCLUSIONS: Bovine pericardium demonstrated a statistically significant decrease in intraoperative suture line bleeding compared with Dacron. Handling characteristics were judged by the surgeons to be superior for BP. Therefore, we believe BP may be an alternative to Dacron when performing patch angioplasty of the carotid artery after endarterectomy.