Immunosuppression in renal transplantation: Long-term clinical trial of a double versus triple therapy regimen

Summary: Sixty-nine renal allograft recipients were randomized to two immunosuppressive regimens: 35 patients received cyclosporine A and prednisolone (PC) while 34 patients received low dose cyclosporine A, prednisolone and short term azathioprine (PCA). the data of 66 patients (34 in PC and 32 in PCA groups) were analysed. the median follow-up periods were 62 months for the PC group and 60 months for the PCA group. There was no difference in graft survival between the two groups but five patients died in the PC group compared to none in the PCA group (graft survival: 88 vs 90% at 1 year and 82 vs 82% at 5 years, P = not significant at any time point; patient survival: 90 vs 100% at 1 year and 88 vs 100% at 5 years, P = 0.05 at 5 years). There was a trend for patients in the PCA group to develop earlier and more frequent rejections (not significant; P = 0.106 and P = 0.062, respectively). There were also more episodes of acute cyclosporine A nephrotoxicity and cytomegalovirus (CMV) infection in the PC group. the mean serum creatinine at 5 years was significantly higher in the PCA group when compared to the PC group (179.8 ± 76.5 μmol/L vs 154.7 ± 41.0 μmol/L; P =0.05). We found that both therapeutic regimens were effective in preventing renal allograft rejections. However, double therapy was associated with higher patient mortality secondary to infection. Patients on triple therapy, on the other hand, were more prone to develop rejections in the early post-transplant period and were associated with less favourable renal function in the long run.     

Frostbite: experimental assessment of tissue damage using Tc-99m pyrophosphate. Work in progress

We designed an experimental model using a new method of freezing to study the pathogenesis and treatment of frostbite. Frostbite was simulated in a manner that closely resembles that which occurs in a natural environment. We used a radionuclide imaging technique to monitor the evolution and extent of tissue damage relative to temperature, rate of freezing, and controlled rewarming. Characteristic sequential changes were demonstrated on sequential nuclear scans. Nonperfusion, followed by perfusion, and finally again by nonperfusion occurred in all areas in which necrosis developed. The reappearance of nonperfusion corresponded to vascular injury and thrombosis evidenced at pathologic examination. We determined that lack of tissue perfusion corresponded to tissue injury. We believe that our experimental model provides an effective means of evaluating potential therapeutic regimens.     

The mutagenic effect of measles virus on cell cultures of different origin.

Differences between strains of measles virus in their mutagenic effect on cells of different animals and man were found. The mutagenic activity of measles virus strains was species-specific. In the process of spontaneous transformation the sensitivity of cells to the mutagen changed.