Comparative study of four different types of intraperitoneal mesh prostheses in rats.

PURPOSE: To compare four types of mesh regarding visceral adhesions, inflammatory response and incorporation. METHODS: Sixty Wistar rats were divided into four groups, with different meshes implanted intraperitoneally: polytetrafluoroethylene (ePTFE group); polypropylene with polydioxanone and oxidized cellulose (PCD); polypropylene (PM) and polypropylene with silicone (PMS). The variables analyzed were: area covered by adhesions, incorporation of the mesh and inflammatory reaction (evaluated histologically and by COX2 immunochemistry). RESULTS: The PMS group had the lowest adhesion area (63.1%) and grade 1 adhesions. The ePTFE and PM groups presented almost the total area of their surface covered by adherences (99.8% and 97.7% respectively) The group ePTFE had the highest percentage of area without incorporation (42%; p <0.001) with no difference between the other meshes. The PMS group had the best incorporation rate. And the histological analysis revealed that the inflammation scores were significantly different. CONCLUSIONS: The PM mesh had higher density of adherences, larger area of adherences, adherences to organs and percentage of incorporation. ePTFE had the higher area of adherences and lower incorporation. The PMS mesh performed best in the inflammation score, had a higher incorporation and lower area of adherences, and it was considered the best type of mesh.

Comparative study of four different types of intraperitoneal mesh prostheses in rats

Abstract Purpose: To compare four types of mesh regarding visceral adhesions, inflammatory response and incorporation. Methods: Sixty Wistar rats were divided into four groups, with different meshes implanted intraperitoneally: polytetrafluoroethylene (ePTFE group); polypropylene with polydioxanone and oxidized cellulose (PCD); polypropylene (PM) and polypropylene with silicone (PMS). The variables analyzed were: area covered by adhesions, incorporation of the mesh and inflammatory reaction (evaluated histologically and by COX2 immunochemistry). Results: The PMS group had the lowest adhesion area (63.1%) and grade 1 adhesions. The ePTFE and PM groups presented almost the total area of their surface covered by adherences (99.8% and 97.7% respectively) The group ePTFE had the highest percentage of area without incorporation (42%; p <0.001) with no difference between the other meshes. The PMS group had the best incorporation rate. And the histological analysis revealed that the inflammation scores were significantly different. Conclusions: The PM mesh had higher density of adherences, larger area of adherences, adherences to organs and percentage of incorporation. ePTFE had the higher area of adherences and lower incorporation. The PMS mesh performed best in the inflammation score, had a higher incorporation and lower area of adherences, and it was considered the best type of mesh.

Does mesenchymal stem cell improve the liver regeneration after the 70% hepatectomy?

PURPOSE:: To evaluate the effects of mesenchymal stem cells on liver regeneration in rats following a 70% hepatectomy. METHODS:: Forty rats were subjected to 70% hepatectomy and then ~106 mesenchymal stem cells (test group), or saline solution (control group), were infused into their livers via the portal vein. Each treatment group was divided into early and late subgroups (euthanized 3 d and 5 d following the operation, respectively). Group comparisons of Albumin, aminotransaminases (AST, ALT), and Alcaline Phosphatase (AP) levels, proliferative index (ki-67+ straining), and mitotic cell counts were conducted. RESULTS:: No significant differences in liver regeneration rate, number of mitoses, proliferative index, or serum levels of albumin, AST, or AP were observed. ALT levels were higher in the test group than in the control group (p<.05). CONCLUSIONS:: Mesenchymal stem-cell therapy did not improve liver regeneration rate 3 d or 5 d after 70% hepatectomy in rats. Likewise, the therapy appeared not to affect liver function, proliferative index, or number of mitoses significantly.

Does mesenchymal stem cell improve the liver regeneration after the 70% hepatectomy?

Abstract Purpose: To evaluate the effects of mesenchymal stem cells on liver regeneration in rats following a 70% hepatectomy. Methods: Forty rats were subjected to 70% hepatectomy and then ~106 mesenchymal stem cells (test group), or saline solution (control group), were infused into their livers via the portal vein. Each treatment group was divided into early and late subgroups (euthanized 3 d and 5 d following the operation, respectively). Group comparisons of Albumin, aminotransaminases (AST, ALT), and Alcaline Phosphatase (AP) levels, proliferative index (ki-67+ straining), and mitotic cell counts were conducted. Results: No significant differences in liver regeneration rate, number of mitoses, proliferative index, or serum levels of albumin, AST, or AP were observed. ALT levels were higher in the test group than in the control group (p<.05). Conclusions: Mesenchymal stem-cell therapy did not improve liver regeneration rate 3 d or 5 d after 70% hepatectomy in rats. Likewise, the therapy appeared not to affect liver function, proliferative index, or number of mitoses significantly.

Incidence of regurgitation after the banded gastric bypass.

BACKGROUND: Frequent regurgitation is a common complication following Roux-en-Y gastric bypass (RYGBP). This study investigated the risk of becoming a chronic regurgitator, by considering silicone ring size and lower esophageal sphincter (LES) function, and their relationship with weight loss. METHODS: 80 morbidly obese patients were randomly selected to undergo surgery using ring length of 62 mm (40 patients, group A) or 77 mm (40 patients, group B), with 6 months' postoperative follow-up. Preoperative esophageal manometry parameters were correlated with occurrence of chronic postoperative regurgitation. Patients were considered to present chronic regurgitation when this occurred on >10 days/month. RESULTS: The groups were homogeneous regarding age, gender, race, weight, BMI (47.8+/-6.1 vs 50.2+/-6.4 kg/m2) and obesity-related diseases. There were 15% more chronic regurgitators in group A than in group B. Chronic regurgitators in group A lost more weight than chronic regurgitators in group B (P=0.026) or non-chronic regurgitators in group A (P=0.016). A greater proportion of chronic regurgitators had LES hypotonia (mean respiratory pressure <14 mmHg) than did non-chronic regurgitators (P=0.008). Logistic regression demonstrated that the chance of being a chronic regurgitator in group A was 4.5 times greater than in group B (P=0.046), and that the chance of a chronic regurgitator having LES hypotonia was seven times greater than of having normal LES pressure (P=0.006). CONCLUSION: Silicone ring size and LES hypotonia are independent prognostic factors for chronic regurgitation following RYGBP. Ring size and chronic regurgitation contribute significantly towards weight loss during the first 6 postoperative months.