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)

In this study, we characterized the sequence of several intrarenal events and evaluated their relative importance in the pathogenesis of unilateral oliguric acute renal failure induced experimentally in rats by complete occlusion of a renal artery for 1 hour. Kidneys were studied prior to occlusion and 1-3 hours and 22-26 hours after release of the temporary occlusion. Renal blood flow measured by an electromagnetic flow transducer was reduced to 40-50% of control during both postocclusion periods. Flow of tubular fluid was markedly reduced, and the damaged kidneys were oliguric. Proximal and distal convolutions were filled with fluid and dilated 1-3 hours after occlusion; their pressures were greatly heterogeneous and were elevated, on the average, to 31 and 16 mm Hg, respectively. Glomerular capillary pressure at this time was normal or slightly increased. Histological sections showed extensive tubular obstruction. We conclude that initially the oliguria is primarily due to intraluminal obstruction in the absence of predominant increases in preglomerular vascular resistance. Observations at 22-26 hours after occlusion indicated acute tubular necrosis. Moreover, the combined involvement of preglomerular vasoconstriction, presisting tubular obstruction, and passive backflow of tubular fluid appeared to be important in the maintenance of the oliguria. Glomerular capillary, proximal intratubular, and peritubular capillary hydrostatic pressures were reduced below control values. After acute volume expansion, the reduced pressures and renal blood flow were reversed, yet the experimental kidneys remained oliguric. Thus, it is clear that tubular obstruction is a significant factor responsible for both the genesis and the maintenance of oliguria in this experimental model of ischemia-induced acute renal failure.
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PMID:Pathogenesis of acute renal failure following temporary renal ischemia in the rat. 119 55

A total of 201 consecutive cadaveric kidney transplantations were performed in 188 patients at the Chinese Great Wall Hospital, Beijing, from October 1977 to May 1990. The overall 1-, 2-, 5-, and 10-year graft survival rates were 75.5%, 64.5%, 37.0%, and 32.9%, respectively. In the last 5 years, these figures have risen to 83.7% at 1 year, 69.5% at 2 years, and 40.8% at 5 years, respectively. The 14 variables correlating to graft survival in the present study were analyzed using the log rank test for univariate analysis and the Cox proportional hazard model for multivariate analysis. The results show that immunosuppressive drug therapy, cold ischemia time, acute tubular necrosis, and infection were significant factors affecting the survival of cadaveric kidney grafts. Triple therapy with low-dose cyclosporin, as compared to conventional immunosuppressive drug therapy, significantly increased the 1-year graft survival rate (90.3% vs 31.3%) but did not influence the long-term graft survival rate after 3 years. The incidence of acute tubular necrosis significantly correlated to the cold ischemia time and influenced the 1-year graft survival. Analysis showed that the lymphocytotoxic crossmatch affected graft survival after 3 years and that most late graft losses were due to chronic rejection, suggesting that histocompatibility is the strongest factor affecting long-term graft survival. A beneficial effect of pretransplant blood transfusions on long-term graft survival was seen in patients treated with conventional immunosuppressive drugs but not in cyclosporin-treated patients.
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PMID:Analysis of prognostic factors affecting renal allograft survival. 141 14

Over a 4 yr-period, 60 children (aged 10 months to 17 yr) received 66 kidney transplants with the same surgical intensive care program, the fist 48 hr-period of which has been analysed in this study. Thirty percent of recipients were transplanted without previous dialysis and in 8%, body weight was below 10 kg at the time of surgery. The duration of anesthesia was 4.4 +/- 1.0 h and 32% received locoregional anesthesia. The mean duration for cold ischemia was 14.7 +/- 11.7 h and 26 +/- 7 min for warm ischemia; diuresis began during the operation in 79% of the patients. Routine vascular filling consisted of standard isotonic solute (11 +/- 4 ml/kg/h) associated with mannitol infusion; 59% of recipients required 20% human serum albumin and 42% blood transfusion. Post-operative diuresis was 7.4 +/- 6.0 ml/kg/h during the first 24 h, and sometimes resulted in hypovolemic episodes; 9% of the patients had primary non-functioning kidneys (4 transient acute tubular necrosis; 2 vascular thrombosis) and 4% required dialysis; the 1-yr survival rate was 82% for the grafts and 98% of the patients.
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PMID:[Resuscitation during renal transplantation in children]. 166 35

There have been recent reports of rhabdomyolysis associated with cocaine abuse. The pathologic findings from these cases have not been described. Pathologic abnormalities in two fatalities with cocaine-associated rhabdomyolysis, including one with hyperpyrexia, acute renal failure, and disseminated intravascular coagulation, are discussed in detail. Skeletal muscle in both cases showed necrosis without evidence of vasculitis, polarizable foreign crystals, or other specific lesions. The individual with renal failure showed acute tubular necrosis with granular myoglobin casts in tubules. The mechanism of cocaine-associated rhabdomyolysis is unclear, but potentially includes ischemia due to vasoconstriction, direct toxicity, hyperpyrexia, and increased muscle activity from agitation or seizure. Adulterants may also play a role. In unexplained cases of rhabdomyolysis, toxicologic evidence of cocaine should be sought. In those cases of rhabdomyolysis associated with acute renal failure, the presence of cocaine in blood may be prolonged because of impaired renal clearance.
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PMID:Rhabdomyolysis associated with cocaine abuse. 174 98

In this review, structural and ultrastructural alterations in the kidney in acute renal failure are described and illustrated in some detail. Morphologic findings in clinical and experimental acute renal failure of the type produced by ischemia and some nephrotoxins, so-called 'acute tubular necrosis' are compared and discrepancies between findings in clinical specimens and experimental models noted and discussed. Since perturbations in intrarenal electrolyte species almost surely play a major pathogenic role in renal injury and dysfunction, correlations between altered intrarenal electrolyte transport and abnormal cellular ion concentrations, and morphologic alterations are emphasized in this review.
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PMID:Structural correlates of renal electrolyte alterations in acute renal failure. 175 23

Acute tubular necrosis (ATN) after renal transplantation is related to the duration of warm and cold ischemia and leads to temporary or permanent impairment of graft function. An increased incidence of ATN has been reported since the introduction of cyclosporin A. Kidney damage resulting from hypothermic storage is generated in part during reperfusion rather than during ischemia itself. Potential mediators of the reperfusion injury are oxygen-derived free radicals. Therefore, the influence of two oxygen radical antagonists, allopurinol and superoxide dismutase, was evaluated in syngeneic rat kidney transplantation with and without concurrent administration of cyclosporin A. At 15 h cold ischemia, 28-day survival increased from 8% (no treatment) to 22% (superoxide dismutase), 33% (superoxide dismutase and allopurinol), and 73% (allopurinol). Cyclosporin A cotreatment (10 mg/kg over 14 days) resulted in survival rates of 0%, 25%, 17%, and 50% for the respective treatment groups. The results of serum creatinine values and morphological evaluation of biopsies paralleled the survival rates. Cyclosporin A nephrotoxicity was evidenced by significant serum creatinine elevations throughout the 28-day period of observation. In conclusion, allopurinol significantly protects syngeneic rat kidney transplants against a critical duration of cold ischemia. Under the conditions of this experiment, allopurinol was clearly superior to superoxide dismutase treatment. Cyclosporin A nephrotoxicity was, however, not ablated by the oxygen radical antagonists employed.
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PMID:Protective effect of allopurinol and superoxide dismutase in renal isografts in cyclosporin A-treated rats. 178 Apr 91

Atrial natriuretic factor (ANF) ameliorates renal damage in animal models of acute ischemic renal failure. Consequently, ANF could blunt acute tubular necrosis related to ischemia that occurs frequently in cadaveric renal transplants. Ten pairs of cadaveric kidneys were transplanted into 20 recipients. Paired recipients received either alpha-human ANF (hANF) or vehicle alone in a prospective, double-blind protocol. Upon revascularization of the allograft, either hANF or vehicle was administered intravenously as a 50-micrograms bolus, followed by a 4-h infusion (0.1 microgram/kg/min). Glomerular filtration rate ([125I]iothalamate clearance) was measured between 4 and 7 days posttransplant and again between 14 and 21 days posttransplant. Serum creatinine was measured daily when patients were in the hospital, then twice weekly as patients were examined in the outpatient clinic. Between the groups, there was no significant difference in age of the recipients or donors, cold ischemia time, or histocompatibility leukocyte antigen match. Infusion of hANF had no adverse effects. When subjects receiving hANF were compared with those treated with vehicle alone, there were no significant differences in serum creatinine or glomerular filtration rate. Three hANF and four vehicle recipients required dialysis postoperatively. At 1 month posttransplant, 19 of 20 patients had functioning allografts; an allograft from one hANF recipient never functioned. It was concluded that hANF, when given by the protocol of this study, had no beneficial effect on the outcome of cadaveric renal transplantation in humans.
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PMID:Atrial natriuretic factor does not improve the outcome of cadaveric renal transplantation. 183 82

The outcome of renal transplantation in CAPD patients is still controversial since age and clinical differences often make comparison with hemodialysis patients difficult. The aim of this study was to analyse two homogeneous groups of patients, on CAPD and on hemodialysis. 18 CAPD (Group A) and 18 hemodialysis patients (Group B) were selected for a case-control analysis, matched for age, presence of acute tubular necrosis and Cyclosporine A regimen. Group A and B were not different for male/female ratio, donor age, HLA-Dr mismatches, arterial pressure, cold ischemia, or follow-up. Patient, graft survival and number of rejection episodes did not differ significantly at 1 year; serum creatinine at 6 and 12 months and CyA doses at 1 and 6 months were not different; hospitalization rates for first and subsequent admissions did not differ. Infection-free patients were 9/18 in Group A and 15/18 in Group B, with 12 episodes in Group A and 3 in Group B. Post transplant cholesterol levels showed a trend to increase in both groups and triglycerides levels to a decrease; differences in pre and post transplant in body weight were not significant at 12 months. In conclusion, the outcome of transplantation in CAPD patients is not significantly different from that in hemodialysis patients with similar clinical characteristics.
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PMID:Comparison between two dialytic populations undergoing renal transplantation. 198 44

In many studies of renal transplant recipients, acute tubular necrosis has been shown to predispose to a higher rate of graft loss, apparently due to rejection, but the mechanism of this effect is unknown. One possibility is an increased immunogenicity of the graft. To study this possibility, we examined the expression of major histocompatibility complex antigens in kidneys damaged by ischemia, using a mouse model of ischemic ATN. ATN was produced in the left kidney of male CBA mice by temporary clamping of the vascular pedicle for up to 60 min. Class I and II MHC expression was quantified by the extent of binding of monoclonals in radioimmunoassay, after 1 to 35 days in both kidneys. MHC induction was localized by indirect immunoperoxidase staining. Specific steady state mRNA for beta 2 microglobulin and class II were quantified by northern blotting using 32P-labeled probes. Changes in MHC expression were assessed by comparing the ischemically injured left kidney to the control right kidney. By day 1, ATN was evident by histology but there was no change in MHC expression. By day 3, class I was increased in the left kidney by 3-6-fold over the right. In tissue sections, the class I increase was localized to tubular epithelial cells. Starting on day 7 and persisting to day 35, class II was increased by 1.5 to 3 times for the ischemic kidney over the control, primarily in interstitial cells but also in tubular cells. This increase in class II was associated with the appearance of Thy 1.2-positive cells in the interstitial areas. Increased antigen expression was preceded by increased steady state mRNA. Thus unilateral ischemic ATN causes increased MHC expression in tubular cells and the accumulation of an inflammatory infiltrate, both of which may contribute to the increased rate of rejection and graft loss in ischemically injured kidneys.
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PMID:Increased major histocompatibility complex antigen expression in unilateral ischemic acute tubular necrosis in the mouse. 210 46

Recently we reported that maintaining rats on restricted dietary protein regimens prior to renal ischemia will significantly improve postischemic survival rates. This effect required a week or more of maintenance on a restricted protein diet prior to the renal insult and appeared to be independent of the postischemic dietary protein regimen. The present study was designed to evaluate the role of systemic toxicity in this protection. Adult male Sprague-Dawley rats were pair-fed by weight on restricted or high isocaloric protein diets for 8-10 days prior to 45 min of renal ischemia induced by renal pedicle clamping. When placed on a normal dietary protein regimen immediately following ischemia, the rats preconditioned to restricted dietary protein exhibited significantly less acidosis, less hyperkalemia, lower blood urea nitrogen values, and improved survival rates compared with rats preconditioned on a high dietary protein regimen. In order to separate the possible effects of prior dietary protein regimen on acute tubular necrosis suffered during renal ischemia from its effects on the uremic response, bilateral nephrectomies were performed on rats preconditioned for 14 days to low, normal, and high dietary protein regimens. Although all of the rats were placed on the same dietary protein regimen immediately following bilateral nephrectomy, those that had previously been on a lower dietary protein regimen exhibited a significantly reduced uremic response and lived longer. These findings indicate that dietary protein regimen prior to renal ischemia is a risk factor which can have a significant lingering effect on the severity of postischemic systemic toxicity.
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PMID:Dietary protein regimen prior to renal ischemia significantly affects the postischemic uremic response. 237 Sep 27


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