Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association
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Nephrol. Dial. Transplant. · Jan 2010
Effect of the cGMP pathway on AQP2 expression and translocation: potential implications for nephrogenic diabetes insipidus.
Arginine vasopressin (AVP) binding to the V2 receptor (V2R) in renal collecting duct principal cells induces a cAMP signalling cascade resulting in the activation of protein kinase A (PKA), translocation of aquaporin-2 (AQP2) to the apical membrane and an increase in AQP2 expression. Consequently, concentration of urine is initiated. X-linked nephrogenic diabetes insipidus (NDI), characterized by the inability to concentrate urine in response to AVP, is caused by mutations in the V2R gene. Initiation of AQP2 translocation, while circumventing the V2R-cAMP-PKA pathway has been suggested as a putative therapy for these patients. In this respect, the activation of a cAMP-independent and cGMP-dependent pathway for AQP2 membrane insertion by different cyclic guanosine monophosphate (cGMP) pathway activators, such as atrial natriuretic peptide (ANP), l-arginine and 8-bromoguanosine 3',5'-cyclic monophosphate (8-Br-cGMP), has been put forward. However, it is unclear whether they can increase AQP2 expression. ⋯ Our results suggest that while activators of the cGMP pathway are likely beneficial in the treatment of X-linked NDI, their ability to relieve NDI in the patients may be improved when combined with agents stimulating AQP2 expression.
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Nephrol. Dial. Transplant. · Dec 2009
Randomized Controlled Trial Multicenter Study Comparative StudyRandomized controlled clinical trial of corticosteroids plus ACE-inhibitors with long-term follow-up in proteinuric IgA nephropathy.
Immunoglobulin A nephropathy (IgAN) is the most common cause of chronic renal failure among primary glomerulonephritis patients. The best treatment for IgAN remains poorly defined. We planned a long-term, prospective, open-label, multicentre, centrally randomized controlled trial to assess whether the combination of prednisone and ramipril was more effective than ramipril alone in patients with proteinuric IgAN. ⋯ Our results suggest that the combination of corticosteroids and ramipril may provide additional benefits compared with ramipril alone in preventing the progression of renal disease in proteinuric IgAN patients in the long-term follow-up.
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Nephrol. Dial. Transplant. · Nov 2009
The predictive performance of plasma neutrophil gelatinase-associated lipocalin (NGAL) increases with grade of acute kidney injury.
In adult cardiac surgery, the predictive value for AKI of neutrophil gelatinase-associated lipocalin (NGAL) appears to have wide variability. The choice of definition of acute kidney injury (AKI) might, at least in part, account for such variability. ⋯ In adult cardiac surgery patients, the predictive value of NGAL increases with grade of AKI. This observation needs to be taken into account when interpreting any future studies of this biomarker.
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Nephrol. Dial. Transplant. · Nov 2009
Changes in the volume status of haemodialysis patients are reflected in sublingual microvascular perfusion.
After the introduction of sidestream darkfield imaging (SDF) of the microcirculation, it has become clear that in sepsis, microcirculatory alterations can exist in the absence of systemic haemodynamic abnormalities. However, it is unclear whether this phenomenon also occurs in the treatment of end-stage kidney disease (ESKD) where alterations in the volume status of patients occur during dialysis. We tested the hypothesis that volume changes during dialysis directly affect the perfusion of the microcirculation in a group of adult haemodialysis patients. Secondly, we evaluated microcirculatory response to autotransfusion using the Trendelenburg position (TP). ⋯ Sublingual microvascular perfusion is reduced by UF and can be restored temporarily using autotransfusion by TP due to increased venous return. SDF imaging is able to detect these volume changes. SDF imaging and TP could become a useful bedside tool to evaluate the patient's (microvascular) volume status and response to therapy in dialysis or intradialytic hypotension.