Journal of the American Society of Nephrology : JASN
-
J. Am. Soc. Nephrol. · Nov 2006
Ischemic preconditioning provides both acute and delayed protection against renal ischemia and reperfusion injury in mice.
Acute as well as delayed ischemic preconditioning (IPC) provides protection against cardiac and neuronal ischemia reperfusion (IR) injury. This study determined whether delayed preconditioning occurs in the kidney and further elucidated the mechanisms of renal IPC in mice. Mice were subjected to IPC (four cycles of 5 min of ischemia and reperfusion) and then to 30 min of renal ischemia either 15 min (acute IPC) or 24 h (delayed IPC) later. ⋯ Moreover, delayed IPC was not observed in iNOS knockout mice. Both acute and delayed IPC were independent of A(1) adenosine receptors (AR) as a selective A(1)AR antagonist failed to block preconditioning and acute and delayed preconditioning occurred in mice that lacked A(1)AR. Therefore, this study demonstrated that acute or delayed IPC provides renal protection against IR injury in mice but involves distinct signaling pathways.
-
J. Am. Soc. Nephrol. · Oct 2006
Randomized Controlled TrialRevisiting survival differences by race and ethnicity among hemodialysis patients: the Dialysis Outcomes and Practice Patterns Study.
Hemodialysis (HD) patients who are identified as belonging to racial or ethnic minority groups have longer survival than non-Hispanic white HD patients. This study sought to determine to what extent this survival difference is explained by comprehensive adjustment for measurable case-mix and treatment characteristics. A cohort analysis was conducted among 6677 patients between 1996 and 2001 in the American arm of the first phase of the Dialysis Outcomes and Practice Patterns Study, a prospective observational study. ⋯ The associations of race/ethnicity with survival varied little by duration of ESRD and were not influenced substantially by different rates of kidney transplantation among patients who were on HD. The survival advantages for racial and ethnic minority groups on HD are explained largely by measurable case-mix and treatment characteristics. Individual racial minority group or Hispanic patients should not be expected to survive longer on HD than non-Hispanic white patients with similar clinical attributes.
-
J. Am. Soc. Nephrol. · Oct 2006
Association of mortality and hospitalization with achievement of adult hemoglobin targets in adolescents maintained on hemodialysis.
With the use of data from the Centers for Medicare & Medicaid Services' ESRD Clinical Performance Measures Project (October through December 1999 and 2000) linked with US Renal Data System hospitalization and mortality records, whether achieving adult target hemoglobin (Hb) levels in adolescents who are on hemodialysis (HD) was associated with decreased risk for death or hospitalization was assessed. Of 677 adolescents, 238 were hospitalized and 54 died. In bivariate analysis, 11.7% with Hb <11 g/dl at study entry died versus 5% of those with initial Hb > or =11 g/dl (P = 0.001); 40.3% with baseline Hb <11 g/dl were hospitalized versus 31.1% with initial Hb > or =11 g/dl (P = 0.013). ⋯ For hospitalization, no statistically significant difference in risk between Hb categories was found. This observational study of adolescents who are on HD is consistent with adult literature showing decreased mortality in patients who have ESRD and meet adult Hb targets. Further studies in the form of randomized, clinical trials are needed to assess optimal Hb levels for adolescents who are on HD.
-
J. Am. Soc. Nephrol. · Sep 2006
Falling into the doughnut hole: drug spending among beneficiaries with end-stage renal disease under Medicare Part D plans.
The Medicare Part D prescription drug benefit may facilitate provision of medications by subsidizing drug costs. However, beneficiaries with higher drug utilization may face higher out-of-pocket (OOP) costs under the benefit's "doughnut hole" provisions that substantially increase beneficiary cost-sharing. The Medicare Current Beneficiary Survey Cost and Use data for 1997 through 2001 were used to estimate the impact of the standard Part D benefit on drug expenditures. ⋯ Therefore, ESRD beneficiaries face substantial total and OOP annual expenditures for medications, causing most to reach the Part D benefit gap. Higher OOP costs may lead to reductions in spending and medication use with subsequent treatment gaps that may lead to increased use of medical services. As the new legislation takes effect, policy makers who are considering modifications in the program may benefit from further research to monitor patterns and gaps in coverage, medication use and spending, and hospitalization and survival trends.
-
J. Am. Soc. Nephrol. · Aug 2006
Comparative StudyTransplanted mesenchymal stem cells accelerate glomerular healing in experimental glomerulonephritis.
Bone marrow-derived cells contribute to glomerular cell turnover and repair, but the cell types involved are unknown. Whether rat mesenchymal stem cells (MSC) can accelerate recovery from damage in rat mesangioproliferative anti-Thy1.1 glomerulonephritis was studied. After injection into the left renal artery on day 2 after disease induction, fluorescently labeled MSC were detected in 20 to 50% of glomeruli and rare intrarenal vessels but not in the tubulointerstitium, in contralateral kidneys, or in medium controls. ⋯ Double immunostaining of 5-bromo-2'-deoxyuridine-labeled MSC for endothelial, mesangial, or monocyte/macrophage antigens showed that 85 to 95% of MSC that localized in glomeruli on day 6 failed to express these markers. In vitro, MSC secreted high amounts of vascular endothelial growth factor and TGF-beta1 but not PDGF-BB. In conclusion, even low numbers of MSC can markedly accelerate glomerular recovery from mesangiolytic damage possibly related to paracrine growth factor release and not to differentiation into resident glomerular cell types or monocytes/macrophages.