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J Alsina

Publications and source records attributed to J Alsina.

At least 73 records · Page 4Linked to original sources

Renal protective effect of liposomed superoxide dismutase in an experimental warm ischemia model.

Superoxide dismutase (SOD) is a potent scavenger of superoxide radicals produced during normothermic ischemia-reperfusion. Since it has a short half-life, its optimal effect is achieved when it is given prior to reperfusion. The inclusion of SOD in liposomes (lipo-SOD) prolongs its half-life (free SOD: 6 min; lipo-SOD: 4 h). The protective effect of lipo-SOD in a 60-min bilateral renal warm ischemia model was studied. We divided 60 male Wistar rats between two control groups and five study groups according to the drug used (SOD or lipo-SOD) and to the time of SOD administration (prior to ischemia or prior to reperfusion). SOD and lipo-SOD were both given at 20 mg/kg endovenously. Weight, diuresis, creatinine per 100 g (Cr/100 g), and creatinine clearance per 100 g (CrCl/100 g) were studied. Conventional renal histology was performed after reperfusion and on day 7. Renal malondialdehyde, 6 keto PGF 1 alpha, and TxB2 tissue levels were studied after reperfusion. Results showed that the renal protective effect of free SOD on warm ischemic-reperfusion injury depended on the time of administration, being more effective when given before reperfusion. On the other hand, the renal protective effect of liposomed SOD did not depend on the time of administration since efficacy was similar when given before reperfusion or before ischemia. The functional protective effect of liposomed SOD was similar to that of free SOD when they were given prior to reperfusion. Nevertheless, since histological damage observed with liposomed SOD was less than with free SOD, it is suggested that the liposomed galenic form may offer better protection against renal warm ischemia. In addition, liposomed SOD was better at preventing tissue prostanoid generation after renal warm ischemic-reperfusion injury than free SOD. We concluded that liposomed SOD shows a higher renal protective effect against warm ischemia than free SOD.

6-Ketoprostaglandin F1 alpha↗

Prevention of experimental cyclosporine nephrotoxicity by dietary supplementation with LSL 90202, a lysine salt of eicosapentaenoic acid. Role of thromboxane and prostacyclin in renal tissue.

Cyclosporine (CsA) nephrotoxicity is partially mediated by renal vasoconstriction due to an imbalance between vasodilator and vasoconstrictor eicosanoids. LSL 90202 is a purified lysine salt of eicosapentaenoic acid which is a known inhibitor of renal eicosanoid synthesis. The aim of the present work was to determine if chronic dietary supplementation with LSL 90202 prevented CsA nephrotoxicity and to establish the role of thromboxane and prostacyclin in renal tissue. Thirty-three male Sprague-Dawley rats were divided into 4 groups: group 1, CsA in olive oil (n = 10); group 2, isovolumetric olive oil (n = 7); group 3, CsA in olive oil plus LSL 90202 (n = 8); group 4, isovolumetric olive oil plus LSL 90202 (n = 8). CsA and LSL 90202 were given at 20 mg/kg/day. Weight and creatinine clearance (CrCl) were determined before and on days 14 and 30. On day 30 whole-blood CsA was determined and renal tissue processed for renal malondialdehyde, thromboxane B2 and 6-keto-PGF1 alpha measurement and for conventional histology. CrCl was severely reduced in the CsA in olive oil group compared to olive oil and LSL 90202 control groups. On day 30, CrCl in the CsA in olive oil plus LSL 90202 group showed a slight decrease, but the mean CrCl was significantly higher than in the CsA in olive oil group. Trough whole blood CsA levels were not significantly different in both groups given the drug. No morphological differences were found between groups.(ABSTRACT TRUNCATED AT 250 WORDS)

6-Ketoprostaglandin F1 alpha↗

Protective effect of the PAF antagonist BN 52021 in an experimental renal warm ischemia model.

Platelet activating factor is involved in warm ischemic damage. We studied the effect of the PAF receptor antagonist BN 52021 in an experimental model of 60 min of renal warm ischemia in which the left kidney was flushed with Euro-Collins solution and a right nephrectomy was performed. Eighty Wistar rats were divided into a sham-operated group, two control groups, and four study groups, according to the dosage and route of BN 52021 administration. BN 52021 was used in the flush solution at concentrations of 0.1 and 0.5 mg/ml, or intravenously prior to ischemia at 5 and 10 mg/kg body weight. Creatinine clearance per 100 g body weight, fractional sodium excretion, and conventional histology were studied. Rats that received BN 52021 intravenously showed a significantly higher creatinine clearance than controls. Intravenous BN 52021 produced a higher acceleration of renal function recovery at 10 mg/kg than at 5 mg/kg body weight. Conventional histology was better in animals that received BN 52021 at 10 mg/kg body weight than in controls. Addition of BN 52021 to Euro-Collins flushing solution showed no protective effect. We conclude that intravenous BN 52021 shows a renal protective effect against warm ischemia.

Animals↗

Relationship between donor renal interstitial surface and post-transplant function.

Forty-three biopsies were performed between 30 and 60 min after reperfusion. Patients (22 males/21 females, mean age 41 +/- 12 years, mean donor age 32 +/- 14 years) were treated either with antilymphocytic globulin, cyclosporin, and prednisolone (24 cases), or OKT3, cyclosporin, and prednisolone (19 cases). Ten patients had delayed post-transplant renal function (DPRF), defined as haemodialysis requirements after surgery, and seven patients had acute rejection 11 +/- 16 days post-transplant. Kidneys were perfused with a hypertonic solution containing mannitol. All patients were followed up for at least 30 months. During follow-up, five patients lost their grafts due chronic rejection, two patients due to noncompliance and one due to recurrence of focal segmental glomerulosclerosis. One patient died from heart infarction. Biopsies were stained with H&E, Masson's trichrome, periodic acid-Schiff (PAS) and silver methenamine. Interstitial fibrosis, interstitial oedema, tubular vacuolization, and peritubular capillary oedema were measured using a semiquantitative scale. Five 400 x magnification micrographs of cortical interstitium from silver-methenamine-stained sections were used to measure percentage of interstitial surface with a morphometer. Interstitial surface was 18.7 +/- 6.2% (range 3.2-35.3%). A positive correlation was found between interstitial surface and donor age (r = 0.469, P = 0.0015). No relationship was found between warm and cold ischaemia times and tubular vacuolization or peritubular capillary oedema.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Renal vasculitis without hematuria in senile patients].

Systemic vasculitis is a disease whose prognosis has improved considerably with steroid and immunosuppressive treatment, which points up the importance of early diagnosis. In elderly, diagnosis is made more difficult because the frequent onset in the form of a febrile syndrome with non-specific disturbances in general condition. In these patients it is not uncommon that a kidney involvement is what leads to diagnosis of the disease. Hematuria is almost a constant in vasculitis nephropathy. In their absence, acute renal failure in elderly is usually attributed to hemodynamic causes and the frequent presence of iatrogenic tubular factors. This is a report on the case of three elderly patients who presented a febrile syndrome with asthenia, anorexia and weight loss. The three cases progressed to acute renal failure with no disorders in urinary sediment. In two cases was a history of administration of gentamycin, indomethacin and iodated contrast. The clinical diagnosis was toxic and ischemic tubulopathy and, when dialysis became necessary, a renal biopsy was done which showed granulomatous vasculitis, intersticial nephritis and in two cases, necrotizing glomerulitis and crescent formation. Treatment with steroids and cyclophosphamide was started which improved general condition and renal function in one case. Early renal biopsy is advisable in senile patients with non specific systemic symptoms and progressive acute renal failure of unclear origin, even when hematuria is lacking. In this setting, the appearance of underdiagnosed renal vasculitis is possible, and consequent immunosuppressive treatment is a factor for consideration.

Acute Kidney Injury↗

Cyclosporin A (CsA) and azathioprine (AZA) combination in renal allografts with CsA nephrotoxicity.

Cyclosporin A (CsA) is a potent immunosuppressive drug whose effect is well known in the organ transplantation field. Treatment with CsA reduces the incidence of rejection and improves graft survival after renal transplantation (RT). However, to set against the clear advantages of CsA, a most important problem is nephrotoxicity. Scientists are therefore seeking new non-nephrotoxic Cs derivatives, but the search has not yet borne fruit. Teams working in organ transplantation attempt to avoid nephrotoxicity by switching to conventional treatment with azathioprine (AZA), starting 1, 3 or 6 months after transplantation. Conversion from CsA to AZA has not always been successful due to the high incidence of rejection. AZA has also been started immediately after transplantation in combination with CsA at low doses, and in some instances no CsA is administered when oliguric acute tubular necrosis is present. In a previous report, we presented the short-term results of the treatment with a CsA-AZA combination, reducing the CsA dose and giving a moderate dose of AZA in 21 transplanted patients not achieving acceptable graft function. In the present study we analysed the long-term results in a group of patients whose kidney biopsy examination results were compatible with CsA nephrotoxicity.

Acute Disease↗

Antilymphocyte globulin versus OKT3 induction therapy in cadaveric kidney transplantation: a prospective randomized study.

Different induction therapies have been used in renal transplantation to avoid cyclosporine (CsA) nephrotoxicity and early acute graft rejection. This study compares the efficacy of a short course of prophylactic OKT3 to that of antilymphocyte globulin (ALG) in preventing acute renal allograft rejection when administered concomitantly with CsA and steroids. Between March 1988 and December 1990, 140 first-cadaver renal transplant recipients were randomly allocated to two immunosuppression groups--ALG group (n = 68): ALG 15 mg/kg just before transplant surgery, ALG 12 mg/kg the first day after transplant, followed by four doses of 10 mg/kg on alternate days; and OKT3 group (n = 72): OKT3 5 mg just before transplant, followed by four doses of 5 mg/d. Both groups included low-dose CsA and steroids. The incidence of rejection during the first 3 months after transplantation was 15% in the ALG group and 19% in the OKT3 group (NS). Kaplan-Meier estimates of patients free of rejection at 2 years was 85% in the ALG group and 77% in the OKT3 group (NS). The 3-year actuarial graft survival was 82% and 85% (NS), and 3-year patient survival was 97% and 98% (NS), in the ALG and OKT3 groups, respectively. These results indicate that the concomitant association of CsA and ALG or OKT3 constitutes a safe and effective therapeutic strategy that provides a low incidence of rejection and gives good results for patient and graft survival.

Adolescent↗

[Antilymphocyte serum, cyclosporine and corticoids, versus OKT3, cyclosporine, and corticoids in kidney transplantation].

UNLABELLED: The use of the antilymphoblast globulin (ALG) or OKT3 associated with cyclosporine (CyA) and steroids has been useful in kidney cadaveric transplantation. 101 patients who received their first cadaveric renal transplant were randomized according to the immunosuppression used. Group A (n = 53): horse ALG 15 mg/kg just before transplant surgery; ALG 12 mg/kg on the first day after transplant followed by 4 doses of 10 mg/kg on alternate days; Cya p.o 8 mg/kg/d; prednisone 0.25 mg/kg/d. Group B (n = 48): OKT3 5 mg just before transplant followed by 4 doses of 5 mg/d.; CyA and prednisone were administered using the same schedule as group A. RESULTS: the incidence of rejection during the first 3 months was: group A: 13 percent, group B: 17 percent (NS). The probability of being free of acute rejection (Kaplan-Meier) 24 months after transplant was 89 percent in group A and 79 percent in group B (NS). The day of onset of the first acute rejection episode was 25 +/- 20 days after transplant in group A, and 17 +/- 10 day in group B (NS). Incidence of tubular necrosis: group A 21 percent, group B 19 percent (NS).

Adrenal Cortex Hormones↗

Percutaneous transluminal angioplasty in the treatment of renovascular hypertension.

In this study we report our experience in 74 patients with hypertension and renal artery stenosis (42 with atherosclerotic stenosis, 32 with fibromuscular dysplasia) who were followed-up for a mean observation period of 21.7 months after percutaneous transluminal angioplasty (PTA). Stenosis was unilateral in 45 cases, bilateral in 16 and located in the renal artery of a solitary functioning kidney in 13 cases. Ostial involvement was observed in 26 cases. A total of 24 patients showed impaired renal function before PTA. Overall results for BP control were 8 cures (13%), 29 improvements (48%) and 24 (39%) who remained unchanged. Five of the 24 patients (21%) with impaired renal function showed improvement with a decrease in serum creatinine levels of more than 30%. Complications of PTA were rare, being limited to two haematomas at the puncture site which resolved spontaneously. These results emphasize that PTA, an easily repeatable procedure of relatively low risk, short hospital stay and low cost, is a first choice technique in the management of renovascular hypertension.

Adolescent↗