Impact of dialysis modality on posttransplantation results in kidney transplantation.

Studies looking at the type of pretransplantation renal replacement therapy on graft and patient survivals after kidney transplantation have produced conflicting results. Therefore, we studied the effect of pretransplantation dialysis modality (peritoneal dialysis [PD] or hemodialysis [HD]) on transplant outcomes. We performed a retrospective study of 78 patients (39 PD and 39 HD) who had their first renal transplantation between January 1986 and December 2004. Comparisons between groups were made using chi-square tests for qualitative parameters and nonpaired Student t tests for continuous variables. Comparisons between actuarial curves of patient and technique survivals used log-rank tests. The percentages of recipient males, cadaveric donors, transplant-induced diabetes, mean period of dialysis, mean transplantation follow-up, mean duration of first hospital stay, first infection, acute tubular necrosis, and acute rejection episodes were not significantly different among PD versus HD patients, whereas recipient and donor mean ages were significantly higher in HD and PD patients, respectively. There were no differences in graft and recipient survivals among PD versus HD patients. After kidney transplantation, there was no difference between PD and HD patients concerning percentages of infection, acute tubular necrosis, acute rejection episodes or graft and recipient survivals.

Effects of heat exposure on Akt/S6K1 signaling and expression of genes related to protein and energy metabolism in chicken (Gallus gallus) pectoralis major muscle.

In order to improve understanding of the heat-induced changes in muscle growth, we determined the expression of genes related to protein and energy metabolism in the pectoralis major muscle of chickens. We also explored the protein kinase B (PKB also called Akt)/p70 S6 kinase (S6K1)/S6 pathway that mediates anabolic signals thereby regulating metabolism and hypertrophic/atrophic balance. Four-week-old chickens were exposed to 32 or 22 degrees C for 1 week. Chickens from both groups were then fasted for 16 h or left fed, and submitted to an oral administration of glucose-arginine to induce an anabolic response (30-min treatment) or left untreated. High ambient temperature and the associated decrease in feed intake modified the expression of certain energy-related genes (e.g. -40% for PGC-1alpha) and protein metabolism (e.g. about +80% for atrogin-1), but the expression of several muscle metabolism-related genes considered here was unchanged. The capacity for muscle protein synthesis, i.e. RNA/protein ratio, was reduced in warm conditions (approximately -20%). Slightly lower activation of S6 induced by glucose-arginine treatment was found at 32 degrees C compared to 22 degrees C, which might indicate somewhat lower efficiency of mRNA translation. Analysis of glucose/insulin balance suggested changes in glucose metabolism under heat exposure. However, this remains to be characterized.

Interstitial muscle concentrations of rocuronium under steady-state conditions in anaesthetized dogs: actual versus predicted values.

INTRODUCTION: The objective of this study was to compare rocuronium effect (C(e)) and peripheral (C(2)) compartment concentrations predicted by pharmacokinetic-pharmacodynamic (PK-PD) modelling with those measured in plasma (C(p)) and in the interstitial fluid of muscle tissue (C(ISF,u)) by microdialysis in anaesthetized dogs. METHODS: After approval by the Animal Care Committee, eight adult male dogs with a body weight ranging from 7 to 18 kg were anaesthetized with pentobarbital. Each dog received a 2-min rocuronium infusion of 0.15 mg kg(-1) min(-1) followed by a 118-min infusion of 60 microg kg(-1) min(-1) via the right jugular vein. Arteriovenous gradient across the hindlimb was measured at 40, 60, 100 and 120 min. Three microdialysis samples were collected at 40-min intervals. Once the infusion stopped, arterial samples were collected every 2 min for the first 10 min and every 20 min for the next 120 min. Neuromuscular function was monitored using train-of-four stimulation until full recovery. Dogs were then killed and a biopsy of muscle tissue was performed (C(m)). RESULTS: At steady state, the mean C(ISF,u) value was 1353 ng ml(-1). After correction for the unbound fraction in plasma, the mean C(e,corr) and C(2,corr) were 1681 and 1481 ng ml(-1), respectively. At the terminal sampling point, C(m) was 10-fold higher than C(p). CONCLUSION: Unbound concentration of rocuronium measured in the muscle interstitial fluid under steady-state conditions confirms that parametric PK-PD modelling gives reliable estimates of effect site concentrations. Rocuronium accumulates in muscle tissue, probably by non-specific protein binding in the interstitial space.