Decellularization of Trachea With Combined Techniques for Tissue-Engineered Trachea Transplantation

OBJECTIVES: The purpose of this study is to shorten the decellularization time of trachea by using combination of physical, chemical, and enzymatic techniques. METHODS: Approximately 3.5-cm-long tracheal segments from 42 New Zealand rabbits (3.5±0.5 kg) were separated into seven groups according to decellularization protocols. After decellularization, cellular regions, matrix and strength and endurance of the scaffold were followed up. RESULTS: DNA content in all groups was measured under 50 ng/mg and there was no significant difference for the glycosaminoglycan content between group 3 (lyophilization+deoxycholic acid+de-oxyribonuclease method) and control group (P=0.46). None of the decellularized groups was different than the normal trachea in tensile stress values (P>0.05). Glucose consumption and lactic acid levels measured from supernatants of all decellularized groups were close to group with cells only (76 mg/dL and 53 mg/L). CONCLUSION: Using combination methods may reduce exposure to chemicals, prevent the excessive influence of the matrix, and shorten the decellularization time.

role of hepatocyte growth factor in the differentiation of dendritic cells from peripheral blood monocytes

To find out the effects of hepatocyte growth factor [HGF] in the development of dendritic cells [DC] from the peripheral monocytes. The study was carried out in Black Sea Technical University Hospital, Trabzon, Turkey between 2003-2004. Seven different cytokine combinations were employed to assess phenotypical and functional differences of DCs from the peripheral monocytes in serum free culture media. Peripheral monocytes were incubated in media with cytokines for 5 days. The tumor necrosis factor-alpha [TNF-alpha] was added to the cell culture on day 5 and incubated for another 2 days. Surface and co-stimulating molecules on the cells were assessed by flowcytometry. The functional capacity of the DCs was evaluated on day 7 by purified protein derivative loading and subsequent lymphoproliferation test using methyl tetrazolium staining. On the 5th day of incubation DC development was observed in all cytokine groups, but cells were superior in cultures maintained in the presence of interleukin-4 combinations with granulocyte-macrophage colony stimulating factor [GM-CSF] or with GM-CSF+HGF. Moreover, the expression of surface and co-stimulating molecules increased significantly after incubation with TNF-alpha. The effect of PPD loaded-DCs on proliferation of lymphocytes was more striking in HGF containing groups. It was concluded that HGF supplemented cultures exert some additive effects in relation to function of monocyte-derived DCs. But HGF alone does not seem to augment monocyte-derived DC proliferation and maturation significantly

Coagulation and fibrinolysis parameters in type 2 diabetic patients with and without diabetic vascular complications

To investigate the markers of endogenous coagulation/fibrinolysis and vascular endothelial cell function, and to assess the relationships between hemostatic parameters and diabetic vascular complications in type 2 diabetic patients. Materials and Coagulation and fibrinolysis parameters were measured in 92 type 2 diabetic patients [43 male, 49 female, mean age 50.1 ' 13.4 years] with [n = 44] and without [n = 48] vascular diabetic complications, and in 40 nondiabetic healthy subjects [20 male, 20 female, mean age 49.8 ' 15.1 years]. Common lipid parameters were also measured. The plasma levels of fibrinogen, antithrombin III [AT III], plasminogen activator inhibitor-1 [PAI-1], von Willebrand factor [vWF] activity and prothrombin time were found to be significantly increased in the type 2 diabetic patients compared with the healthy subjects. Glycosylated hemoglobin lc was inversely correlated with plasma protein S and activated prothrombin time. Protein C and S activities were positively correlated with plasma vWF activity, and were negatively correlated with plasma t-PA levels. vWF activity was negatively correlated with plasma t-PA levels. AT III levels were positively correlated with plasma total cholesterol levels, plasma low density lipoprotein cholesterol levels, plasma triglycerides and D-dimer levels. Plasma PAI-1 levels and factor V activity in diabetic patients with microvascular complications were significantly higher than those of the diabetic patients without microvascular complications. The plasma PAI-1 and platelet count were increased in patients with diabetic retinopathy compared with the diabetic patients without retinopathy. Plasma PAI-1 levels and factor VII activity were significantly higher in the diabetic patients with nephropathy than in diabetic patients without nephropathy. Plasma concentrations of fibrinogen and PAI-1 were significantly higher in the diabetic patients with neuropathy than the diabetic patients without neuropathy. The data demonstrated that patients with type 2 diabetes mellitus had a hypercoagulable state and hypofibrinolysis, thereby indicating that activation of coagulation with a reduced fibrinolytic activity may contribute to the increased risk of vascular disease in type 2 diabetic patients