Post-transplantation morphological and functional changes in kidneys from expanded criteria donors.

Introduction Despite an increase in the number of cadaver donors and overall organ transplantations, the dramatic increase in the waiting list makes it necessary to reconsider donor criteria. The authors wanted to examine whether differences could exist in the function and/or morphology of transplanted kidneys originated from expanded criteria donors (ECDs) and ideal donors 1 and 5 years after transplantation. Methods Kidney function and histopathologic findings were analyzed and compared 1 and 5 years after transplantation in 97 patients having ECD kidneys and in 178 patients who received ideal donor kidneys (IDK). Results Serum creatinine level was significantly higher (p = 0.001) and estimated glomerular filtration rate was significantly lower (p = 0.003) in patients having ECD kidneys as compared with those with IDK 5 years after transplantation. Morphological changes in the transplanted kidneys, such as tubulitis (p = 0.025) and interstitial inflammation (p = 0.002), were significantly more frequently present in patients with ECD kidneys than in those with IDK 1 year after transplantation. Conclusion Despite an absence of differences in kidney function 1 year after kidney transplantation between patients having ECD and IDK, morphological differences in the transplanted kidneys can be detected between the two groups of patients.

Telemetry monitoring for non-invasive assessment of changes in core temperature after spinal drug administration in freely moving rats.

INTRODUCTION: There are no data available about the effects of spinally administered drugs on thermoregulation in freely moving animals. The first goal of the present study was to throw light on the consequences of intrathecally administered saline as a vehicle on core temperature and motor activity in unrestrained conditions. The second goal was to characterize the effects of morphine on these parameters as a widely used antinociceptive drug in spinal anesthesia, and reveal the potential role of the N-methyl-d-aspartate (NMDA) receptors in these processes. METHODS: For these purposes, male Wistar rats were catheterized intrathecally, and E-Mitter battery-free transponders were implanted intraabdominally to continuously monitor core temperature and locomotor activity. RESULTS: Saline induced a short-lasting hyperactivity accompanied by significant and prolonged hyperthermia that was blunted by systemic paracetamol administration. Morphine had no impact on motor activity; however, it caused high but equivalent degree hyperthermia in a wide dose range (1-15 µg), suggesting that it reached its peak effect. In the highest applied dose (25 µg), the NMDA receptor antagonist kynurenic acid blunted the saline-induced hyperthermia, and all doses caused higher hyperactivity compared to vehicle or morphine injections. In combination, kynurenic acid significantly inhibited the morphine-induced hyperthermia. DISCUSSION: These data suggest that this method might be a valuable tool for investigating the thermoregulatory and locomotor effects of different drugs at spinal level; however, the prolonged effects of intrathecal vehicle injections should also be considered. The results point out that morphine is a very potent hyperthermic drug that may act primarily on the efferent limb of thermoregulation, at least partially, via an indirect NMDA-receptor mediated action mechanism.

Early histopathological changes in new-onset diabetes after kidney transplantation.

BACKGROUND: New-onset diabetes after transplantation (NODAT) is one of the most common complications after kidney transplantation. METHODS: Patients were randomly assigned to receive cyclosporine A-based or tacrolimus-based immunosuppression. Fasting and oral glucose tolerance tests were performed, and the patients were assigned to one of the following 3 groups, on the basis of the results: normal, impaired fasting glucose/impaired glucose tolerance, or NODAT. NODAT developed in 14% of patients receiving cyclosporine A-based immunosuppression and in 26% of patients taking tacrolimus (P = .0002). RESULTS: Albumin levels were similar, but uric acid level (P = .002) and the age of the recipient (P = .003) were significantly different between the diabetic and the normal groups. Evaluation of tissue samples revealed that acute cellular rejection and interstitial fibrosis/tubular atrophy were significantly different in the NODAT group. Changes in the Banff score provided significant difference regarding tubulitis and interstitial inflammation (P = .05). CONCLUSIONS: The pathological effect of new-onset diabetes after kidney transplantation can be detected in the morphology of the renal allograft earlier, before the development of any sign of functional impairment.

Functional and morphological changes in kidneys from marginal donors.

Despite the increased number of cadaver donors and overall organ transplantations, we have observed a dramatic increase in the waiting list. We evaluated transplantations performed using marginal (n = 63) and "ideal" or optimal donors (n = 86). Donor and recipient functional and histopathological data were studied at 1 and 5 years after transplantation. Among the marginal donor group, we investigated whether the age or pre-existent hypertension in the donor showed a strong impact on the functional deterioration of the grafts. Twenty-three graftectomies were performed in marginal, and 39 in ideal recipients (P = .002). Evaluating graft function, at 5 years, we observed the serum creatinine level (P = .0001) and the estimated glomerular filtration rate (P = .003) are significantly different between the two groups. At this time there was a significant difference in the serum creatinine level of patients who were older than the age of 55 years compared with those who showed hypertension (P = .0003). Evaluating morphological changes in the kidneys, acute rejection episodes (P = .0004) and interstitial fibrosis/tubular atrophy (P = .002) were significantly greater among the marginal versus the ideal groups. At 1 year after kidney transplantation, despite no significant difference regarding renal function, they were significant in the histology of marginal versus ideal donor kidneys.