Inter-alpha-trypsin inhibitor heavy chain 4 as a marker of acute rejection in pancreas allotransplantation in pigs.

BACKGROUND/AIMS: An early, simple, and reliable marker for acute pancreatic allograft rejection is not available. Inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4) is an interleukin-6-dependent acute-phase positive protein that can act as an anti-inflammatory protein. We studied the response of the ITIH4 in pigs undergoing pancreas allotransplantation (PT) and evaluated this protein as a biomarker for acute graft rejection. METHODS: PT with enteric drainage of the exocrine secretion and systemic venous drainage was performed on 12 Landrace pigs. No immunosuppression was administered. Serum concentrations of glucose, amylase, lipase, insulin, C-peptide, and ITIH4 were determined daily. RESULTS: The response of ITIH4 to PT was early, intense, and prolonged, with 2 peaks in serum concentration. The first peak, which started on day 1 and reached maximum (around 6 mg/dL) on day 3, was attributed to the systemic acute phase response to surgical stress. The second peak, which exceeded the first peak and reached maximum (>8 mg/dL) on day 6, began when the recipients were still normoglycemic, and preceded onset of the diabetic state caused by acute graft rejection by an average of 4 days. CONCLUSION: Serum ITIH4 could help to predict subclinical acute graft rejection after PT in pigs.

Lipid peroxidation in ischemia-reperfusion oxidative injury of the graft preserved in Celsior and University of Wisconsin solutions on a pig pancreas transplantation model.

BACKGROUND: Graft pancreatitis (GP) is one the main technical problems associated with pancreas transplant (PT). It occurs in 20% of patients representing a risk factor for thrombosis and cause of graft loss. GP is related to oxidative effects from oxygen-derived free radicals (OFR) in ischemia-reperfusion injury. We evaluated lipid peroxidation by the OFR in the PT of pig organs preserved with either Celsior or Wisconsin solutions. METHODS: In Landrace pigs we performed 24 pancreas allografts, which were preserved 18 or 24 hours: 12 with Celsior solution (CS) and 12 with Wisconsin solution (UW). No immunosuppression was administered. The oxidative effects were determined by quantification of malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA) and of the carbonyl groups of proteins in our pancreatic tissue samples and measured at different times: (A) baseline in the donor, (B) after perfusion of the graft, (C) after the ischemia period, and (D) 30 minutes after ischemia-reperfusion of the graft. RESULTS: The MDA and 4-HDA values were similar in conditions A, B, and C, but showed an extraordinary increase after ischemia-reperfusion in D, among both the 18- or 24-hour preserved grafts and in the same proportion with CS and UW. The carbonyl groups of the proteins rose in conditions B and C (cold ischemia), but less so in state D (reperfusion). CONCLUSIONS: The oxidative injury of a pancreatic graft preserved for 18 or 24 hours occurs during reperfusion, with an extraordinary intensity, but similarly with CS and UW, an observation that may help to explain graft pancreatitis.

Gamalgamation: current situation.

A review of the historic evolution of gallium alloys and their manipulation characteristics is presented. Although they have similar, or even better, mechanic properties than modern silver amalgams, their use is restricted. This restriction is due to difficulties in their manipulation, their tendency to corrosion, their controversial biocompatibility and the lack of knowledge about gallium's environmental impact. However gallium alloys are still considered as improvable alternatives to silver amalgams.