Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022672 (acute tubular necrosis)
 2,175 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The presence of delayed graft function (DGF) following cadaver donor renal transplantation is associated with inferior graft survival as well as decreased patient survival. Delay in onset of function eliminates a valuable indicator of allograft viability, which is not easily replaced by standard diagnostic procedures. The purpose of this study was to demonstrate that a new clearance technique could be used to measure renal function minute to minute and under conditions similar to those observed in humans in the immediate posttransplantation period. A monkey model was used to provide controlled conditions. Increasing levels of ischemic injury were produced in 12 Rhesus monkeys by renal hilum cross-clamping. Real-time measurements of glomerular filtration rate (GFR) were obtained from the rate of clearance of the extracellular fluid of the GFR agent 99mTc-DTPA, as measured with a specially designed external radioactivity counting device called the ambulatory renal monitor, or ARM. GRF was measured every 2-5 min as the slope (k) of the log of activity measured minute to minute versus time. GFR measurements were correlated with blood urea nitrogen (BUN), plasma creatinine (Cr), routine light microscopy, and measurement of proliferating cell nuclear antigen (PCNA), a marker of cell proliferation. Large changes in renal function due to ischemia or ureteral obstruction were observed within minutes. In addition, the rate constant on Day 1 was predictive of peak serum Cr(R =--0.86, R2=.74, p = .0001). Acute tubular necrosis (ATN) resolution was reflected more quickly when using the rate constant (Day 1) than when using either BUN or plasma Cr (Day 3-4). Because of renal functional reserve, BUN and plasma Cr were relatively insensitive indicators of mild to moderate reductions in GFR as compared with the rate constant. We conclude that ARM is a simple method which provide an accurate, near real-time GFR readout with potential applications not only for the clinical management of patients with DGF, but also as a research tool in acute renal failure (ARF).
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PMID:Real-time monitoring of renal function during ischemic injury in the rhesus monkey. 857 Aug 62

The significance of poor medullary reperfusion in the etiology of acute tubular necrosis during renal transplantation is poorly understood. Our objective was to determine the kinetics of renal hemoglobin oxygenation using near-infrared spectroscopy during renal transplantation, to provide a framework against which the timing of mitochondrial dysfunction could be considered. New Zealand White rabbit kidneys were flushed with hypertonic citrate solution (0-2 degrees C and autografted immediately (group 1) or stored at 0-2 degrees C for 72 hours before autografting (group 2). Changes in oxyhemoglobin (HbO2) and deoxyhemoglobin (Hb) were monitored by near-infrared spectroscopy for 3 hours of reperfusion. Intrarenal perfusion was evaluated separately by barium sulfate angiography. Reperfusion resulted in rapid increases in HbO2 within 1 minute in both groups. Group 1 HbO2 fell sharply to a minimum at 3 minutes but recovered by 20 minutes; group 2 changes were similar, but there was no recovery (P<0.05 by 10 minutes). Hb increased rapidly in both groups upon reperfusion but in group 2 was significantly greater after 10 minutes (P<0.05). Total hemoglobin levels were similar in both groups. Renal hemoglobin saturation was 69% at 1 minute in both groups; there was no significant change in group 1 but a profound desaturation in group 2 to 25% at 10 minute (P<0.005) and no recovery thereafter. Barium sulfate distribution was normal in all group 1 kidneys; cortical distribution was normal in all group 2 kidneys, but medullary perfusion was poor for the first 60 minutes. Renal hemoglobin oxygenation kinetics as determined here do not correlate with the timing of mitochondrial dysfunction previously reported (Thorniley et al., Kidney International, 1994; 45: 1489). We conclude that secondary ischemia during reflow is not the only mechanism leading to acute tubular necrosis.
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PMID:Hemoglobin oxygenation kinetics and secondary ischemia in renal transplantation. 860 68

Studies in the rat have pointed to a role for intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of acute tubular necrosis. These studies used antibodies, which may have nonspecific effects. We report that renal ICAM-1 mRNA levels and systemic levels of the cytokines IL-1 and TNF-alpha increase 1 h after ischemia/ reperfusion in the mouse. We sought direct proof for a critical role for ICAM-1 in the pathophysiology of ischemic renal failure using mutant mice genetically deficient in ICAM-1. ICAM-1 is undetectable in mutant mice in contrast with normal mice, in which ICAM-1 is prominent in the endothelium of the vasa recta. Mutant mice are protected from acute renal ischemic injury as judged by serum creatinine, renal histology, and animal survival . Renal leukocyte infiltration, quantitated morphologically and by measuring tissue myeloperoxidase, was markedly less in ICAM-1-deficient than control mice. To evaluate whether prevention of neutrophil infiltration could be responsible for the protection observed in the mutant mice, we treated normal mice with antineutrophil serum to reduce absolute neutrophil counts to < 100 cells/mm3. These neutrophil-depleted animals were protected against ischemic renal failure. Anti-1CAm-1 antibody protected normal mice against renal ischemic injury but did not provide additional protection to neutrophil-depleted animals. Thus, ICAM-1 is a key mediator of ischemic acute renal failure likely acting via potentiation of neutrophilendothelial interactions.
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PMID:Intercellular adhesion molecule-1-deficient mice are protected against ischemic renal injury. 861 29

The efficacy and safety of (1-28) alpha-human ANP in preventing acute tubular necrosis (ATN) in cadaveric renal transplantation was tested by comparing ANP infusion with a maximal hydration (MH) regimen which we previously reported as effective in lowering the incidence of ATN (1, 2). Since the production of endogenous ANP increases with volume overloading (3), we hypothesized that increased endogenous ANP production may contribute to the beneficial effects of MH in renal transplant recipients. We thus conducted an open randomized study comparing the effect on early renal allograft function of MH (control group) versus moderate hydration plus ANP infusion (ANP group). Forty patients were blindly paired in two groups of 20 according to the duration of cold ischemia time (mean +/- 2 h). The demographic characteristics of donors and recipients were similar. Using a Swan-Ganz catheter, hemodynamic parameters were monitored for 4 h after transplantation. The group receiving ANP and moderate hydration was perfused to a mean pulmonary arterial pressure (PAP) of < or = 20 mmHg. The PAP in patients receiving MH was driven to > or = 25 mmHg. In the ANP group, a bolus of 100 micrograms of ANP was infused into the graft's renal artery at the time of unclamping, followed by 24 h of continuous intravenous infusion at 0.03 microgram/kg/min. Thereafter, the patients received ANP at a rate of 0.01 microgram/kg/min until the serum creatinine reached < 2 mg/dl. As a consequence of the hydration regimen, the PAP at unclamping was lower in the ANP group than in the control group; 20 +/- 3 and 26 +/- 4 mmHg, respectively (p < 0.05). The ANP plasma levels were significantly higher during the first 3 d in the ANP group (p < 0.001). The median recovery rate of renal function was similar in both groups. No patients in the ANP group experienced ATN while 4 patients (20%) in the control group did (p = 0.125). The need for hemodialysis was markedly reduced in the ANP group compared to the control group (1 ANP-treated patient required dialysis once whereas 5 patients from the control group underwent dialysis a total of 26 times; p = 0.068). ANP administration was well-tolerated and no hypotensive episodes were reported. This preliminary study suggests that ANP infusion is at least as effective as maximal hydration in preventing ATN and represents an efficient alternative for transplantation centers which do not use maximal hydration as a standard regimen in managing kidney allograft recipients.
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PMID:Effect of 1-28 alpha-h atrial natriuretic peptide on acute renal failure in cadaveric renal transplantation. 864 92

To assess the impact of long-lasting acute renal failure after renal transplantation on late graft prognosis, we compared the risk factors and outcome in renal allografts with delayed function for >3 weeks after renal transplantation (long-lasting delayed graft function [LLDGF]) (group A, n=64), and in four control groups: group B, initially functioning grafts (n=322); group C, grafts with delayed function for <2 weeks after transplantation (n=110); group D, grafts with delayed function for 14 to 20 days after transplantation (n=57); and group E, never-functioning grafts (n=88). Donor asystolia or instability, stroke as a cause of donor's death, and prolonged cold ischemia and vascular surgical times were some predictors of LLDGF. Overlap was important, but 43% of patients of group A, 15% of group B, 25% of group C, 31% of group D, and 40% of group E (P<0.01) presented two or more risk factors for severe acute tubular necrosis after transplantation. Acute rejection and early complications were very frequent in group A. Also, patient survival was significantly decreased in group A, due to a higher incidence of infectious mortality. Graft survival was moderately (NS) decreased in group A. Serum creatinine was initially higher in patients of group A, but differences disappeared after the second year. However, late proteinuria was more frequent in group A, and there was also a trend for a higher prevalence of hypertension in this group. LLDGF cannot be reliably predicted at the time of renal transplantation. The main consequence of LLDGF is an excess mortality, while the impact on late graft function is less significant. Short-lasting delayed graft function does not seem to have a negative impact on the outcome of renal transplantation.
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PMID:Outcome of grafts with long-lasting delayed function after renal transplantation. 869 42

The present study was designed to determine whether the administration of free radical scavengers, superoxide dismutase (SOD), catalase or dimethylsulfoxide (DMSO) is able to ameliorate ischemia/reperfusion injury in the canine kidney and also ascertain whether or not a relationship exists between oxygen free radicals and membrane-bound Na(+)-K(+)-ATPase activity. In 23 dogs, the vascular pedicle of the left kidney was clamped for 75 min at room temperature. The experimental animals received free radical scavengers for 30 min starting at 2 min prior to reperfusion. Renal tissue specimens were enzyme-histochemically examined regarding the activity of membrane-bound Na(+)-K(+)-ATPase, and a marked reduction just before reperfusion was revealed. The SOD- and the DMSO-treated groups showed a marked recovery of the membrane-bound Na(+)-K(+)-ATPase activity; however, the untreated and the catalase-treated groups still demonstrated a marked reduction 1 day after reperfusion. At the same time, widespread acute tubular necrosis in the cortex was observed in the untreated and catalase groups in comparison with the SOD and the DMSO groups. In addition, the SOD and the DMSO groups significantly preserved better renal function. Based on these findings, it was thus concluded that free radical scavengers ameliorate the recovery of depressed membrane-bound Na(+)-K(+)-ATPase activity and ischemia/reperfusion injury in the canine kidney.
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PMID:The influence of oxygen free radical scavengers on the reduction of membrane-bound Na(+)-K(+)-ATPase activity induced by ischemia/reperfusion injury in the canine kidney. 873 Apr 34

The purpose of this retrospective study was to evaluate results of non-heart-beating donor (NHBD) kidney transplantation. Between Jan 1986 and Dec 1994, 80 out of 582 cadaveric kidneys were harvested from NHBD (31.9 min +/- 24 after cardiac arrest). The results in the NHBD group (76 recipients) were compared with those obtained after transplantation of kidneys harvested from heart-beating donors (HBD) with respect to early graft function, and the graft and recipient's survival. Both groups were matched for sex, age, PRA level, number of HLA mismatches, and cold ischemia time. Triple immunosuppression therapy was used in both groups. Acute tubular necrosis (ATN) was observed significantly more frequently in the NHBD group (50 of 76 recipients vs 33 of 100 in the HBD group). The striking finding of this study was that the occurrence of primary non-function was the same in both groups and that the main cause of it was acute rejection. The 1-year patient and graft survival rates were 98.7% and 81.6% for the NHBD group and 99% and 90% for the HBD group, respectively. There was also no statistical difference in the serum creatinine concentration in both groups. We concluded that despite an increased incidence of ATN in the NHBD kidney recipients, the long-term results are good and comparable with those in the HBD group.
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PMID:Transplantation of kidneys harvested from non-heart-beating donors: early and long-term results. 895 97

Previous experimental and human data suggests a detrimental effect on the course of acute renal failure related to exposure of blood to artificial dialysis membranes of poor biocompatibility. We performed a 2.5-year prospective randomized trial to compare the clinical course of acute renal failure (post-operative ischemic acute tubular necrosis, ATN) in patients receiving a cadaveric renal transplant requiring supportive hemodialysis in the immediate post-transplant setting. Patients were randomized to either a cuprophane or polymethylmethacrylate (PMMA) conventional hollow fiber dialyzer. All patients received a standard immunosuppressive regimen which included induction therapy with either horse anti-thymocyte gamma globulin (ATGAM) or the murine anti-CD3 monoclonal antibody (OKT3). Of 53 patients randomized, 17 were excluded (2 for intervening biopsy-proven rejection prior to recovery from ATN, 10 for primary graft nonfunction and 5 for other reasons), leaving 36 evaluable cases of uncomplicated ATN, 18 in each group. There was no difference by age, race, gender, cause of ESRD, immunosuppressive regimen, cold or warm ischemia time, use of pre-transplant dialysis, percent oliguria or the incidence of intra-dialytic hypotension between the 2 groups. There was no difference in the mean time to recovery from ATN posttransplant (8.9 days in the cuprophane group vs 9.5 days in the PMMA group, p = NS) or in the average number of hemodialysis treatments required (3.6 in both groups, p = NS). There was also no difference in long term allograft outcome in terms of the nadir serum creatinine, the number of episodes of subsequent acute rejection or in the development of chronic rejection. An intent-to-treat analysis of all 53 originally randomized patients similarly yielded no significant differences. A subsequent, non-randomized study using a membrane of intermediate biocompatibility (Hemophan) also showed no difference in recovery time from ATN. Bioincompatible membranes do not seem to have a significant clinical impact on the course of recovery of this form of acute renal failure. The striking benefits of biocompatibility in the course of ARF seen in other human trials may relate more to the non-renal systemic toxic effects of bioincompatibility.
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PMID:Biocompatible dialysis membranes and acute renal failure: a study in post-operative acute tubular necrosis in cadaveric renal transplant recipients. 898 57

Rupture of a renal allograft (RAR) is an uncommon but serious complication of renal transplantation. A recent RAR prompted a review of our experience, with the purpose of (1) identifying conditions that may predispose this complication and (2) defining strategies for prevention. A 5-yr, consecutive living-related (LRD) and cadaver donor (CD) cohort of 331 patients was studied retrospectively. Twelve patients (3.6%) had RAR. Donor characteristics, procurement and preservation conditions, and recipient characteristics were major study categories. Data analysis was computer-based and included multivariate analysis. The nine White and two Black cadaver donors were "ideal", mean age 29 yr, with mean high creatinine (CR) of 1.3 and terminal CR of 1.1 mg/dl and mean terminal urine output of 423 ml/min. Nine of 11 CD had low-dose dopamine use (terminal, mean 8, range 5-13 micrograms/kg/min). Eleven of 11 donors had procurement en-bloc, 9 of which were multiple organ procurement. All had 4+/4+ flush and cold storage with UW solution. Mean cold ischemia time (CIT) was 22 h, 28 min (range 15 h, 16 min to 40 h). For patients with RAR mean age was 39 yr; there were 12 Black patients and 7 males, 5 females. HLA match was 1 antigen (AG) for 3, 2 AG for 8, and 4 AG for 1 (mean 1.9). Nine patients had delayed or declining renal function requiring dialysis. The panel reactive antibody was at peak, mean 47% (range 0-100%) and current, mean 18% (range 0-84%). Six of 12 had OKT3 therapy at time of RAR and six had biopsies. Day of RAR was mean 10, median 9 (range 4-21). Pain and drop in hematocrit were observed in most. There was one fatality (8%), and all kidneys were removed. All kidneys showed at least minimal rejection but six had severe acute tubular necrosis (ATN) with edema and minimal rejection. Statistically significant associations with RAR were older recipient age (p = 0.01), donor-recipient race mismatch (White donor to Black recipient) (p = 0.007), and dialysis requirement (p < 0.001). Other variables were not statistically correlated: gender, race, CIT, transplant number, LRD vs. CD, peak or current PRA, and total HLA and BDR mismatch. The data suggest that ATN and rejection act synergistically to cause RAR and that early delayed function requires intensive and perhaps novel immunosuppression, especially in Black recipients.
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PMID:Renal allograft rupture: a clinical review. 899 57

The main functional change in patients with acute renal failure (ARF) is a decrease in glomerular filtration rate (GFR). The virtual complete recovery of renal function in those patients who survive ARF, as well as the minimal renal histological abnormalities during ARF when the GFR is less than 10 ml/min, suggest that a major component of the renal tubular cell injury is sublethal or reversible. Experimental models of acute tubular necrosis frequently have placed the emphasis on irreversible proximal tubular cell death. The nature of the renal tubular cell injury in ischemic acute renal failure, however, includes not only cell death (necrosis or apoptosis) but also sublethal injury causing cell dysfunction. The role of intracellular calcium, the calcium-dependent enzymes calpain, phospholipase A2 and nitric oxide synthase (NOS), in the pathophophysiology of this renal tubular cell injury during hypoxia/ischemia is described. The effects of calpain and nitric oxide (NO) on the cytoskeleton and cell adhesion are discussed. Potential mechanisms whereby tubular injury leads to a profound fall in GFR, including increased tubuloglomerular feedback and increased distal tubular obstruction, in ischemic acute renal failure are proposed.
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PMID:The nature of renal cell injury. 915 Apr 42


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