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Abdulgaffar Vural

Publications and source records attributed to Abdulgaffar Vural.

10 recordsLinked to original sources

Hyperbaric oxygen treatment augments the efficacy of a losartan regime in an experimental nephrotic syndrome model.

BACKGROUND/AIMS: Proteinuria is associated with oxidant stress and inflammation. Hyperbaric oxygen (HBO) treatment has anti-inflammatory and anti-oxidant effects. The aim of the study was to investigate the benefits of HBO treatment on an experimental nephrotic syndrome model. METHODS: 50 male Sprague-Dawley rats weighing 255 +/- 39 g were housed. Forty rats were injected 6 mg/kg adriamycin into tail veins under anesthesia to induce nephrosis, while 10 rats were spared as sham control. After the stabilization of proteinuria at the sixth week, the rats were treated for 6 weeks by losartan (n = 10, 30 mg/kg/day), HBO (n = 10, 2.8 atmosphere absolute, 90 min/day), HBO + losartan (n = 10) and vehicle (n = 10). Protein carbonyl (PCO), superoxide dismutase (SOD) and glutathione peroxidase (GPx) were analyzed from tissue specimens. Biochemical markers were studied from venous samples and 24-hour urine was collected for proteinuria. The surviving animals at 12 weeks (vehicle group (n = 6), HBO (n = 6), losartan (n = 8), HBO + losartan (n = 10) were sacrificed. Glomerular sclerosis, tubulointerstitial and blood vessel changes were determined by semiquantitative scoring. RESULTS: The PCO levels increased (p < 0.001), and the GPx and SOD levels decreased (p < 0.001 for both) in the nephrotic rats. In losartan and HBO groups GPx levels increased (p = 0.001, p = 0.002 respectively), but PCO and SOD levels did not change. The combination of HBO with losartan significantly increased the GPx and SOD levels (p = 0.001 for both) and decreased PCO levels (p = 0.005). HBO but not losartan significantly reduced proteinuria (p < 0.001). The combination of HBO and losartan reduced proteinuria better than the single losartan regime (p < 0.001). The effect of the combination was also noticed on the histological examination of the kidneys. The activities, appetites, weight gains, and improvement of edema were better in the HBO combined with losartan regime. CONCLUSIONS: These results indicate that the addition of HBO therapy to a conventional regime, angiotensin receptor blockers, has significant benefits in the management of proteinuria. Future clinical studies are needed to elucidate the role of HBO and other antioxidant strategies in the treatment of proteinuria.

Animals↗

The determinants of endothelial dysfunction in CKD: oxidative stress and asymmetric dimethylarginine.

BACKGROUND: Oxidative stress is related to endothelial dysfunction (ED) and cardiovascular outcomes in patients with chronic kidney disease. Increased asymmetric dimethylarginine (ADMA) levels are among the main causes of ED. We aim to investigate any association between ED and ADMA levels, as well as levels of oxidative stress markers, in patients with chronic kidney disease. METHODS: One hundred fifty-nine patients without diabetes with chronic kidney disease were studied. Staging was performed according to glomerular filtration rate, determined as stages 1 to 5 according to the Kidney Disease Outcomes Quality Initiative (n = 30, 33, 28, 32, and 36, respectively). The control group consisted of 30 healthy subjects. Oxidative stress markers (plasma malondialdehyde [MDA], erythrocyte superoxide dismutase [SOD], glutathione peroxidase [GSH-Px]), trace elements (erythrocyte zinc [EZn], erythrocyte copper [ECu]), plasma selenium (Se), and serum ADMA were studied. Brachial artery endothelium-dependent vasodilatation (FMD) was calculated for all. RESULTS: FMD, SOD, GSH-Px, EZn, ECu, and Se values were lower, whereas MDA and ADMA levels were higher in patients than controls. Glomerular filtration rate correlated negatively with MDA and ADMA levels and positively with FMD, SOD, and GSH-Px values. These parameters were significantly different among patients with stages 2, 3, 4, and 5 (hemodialysis group; P < 0.001 for all). Regression analysis showed that ADMA (beta = -0.228; P < 0.01), SOD (beta = 0.405; P < 0.001), and oxidized low-density lipoprotein levels (beta = -0.428; P < 0.001) were related independently to FMD, whereas glomerular filtration rate was not involved in the model. CONCLUSION: The present results imply that FMD, oxidative stress, and ADMA levels all are associated with stage of chronic kidney disease. Additionally, levels of oxidative stress markers and ADMA independently determine endothelial function.

Adult↗

Endothelial functions improve with decrease in asymmetric dimethylarginine (ADMA) levels after renal transplantation.

BACKGROUND: Chronic kidney disease (CKD) is associated with increased cardiovascular events. The relationships between the markers of inflammation and endothelial dysfunction were investigated both before and after living donor kidney transplantation. METHODS: Twenty-seven renal transplant patients were studied. Eleven patients (six male, five female) were on cyclosporine A, whereas 16 patients (nine male, seven female) were treated with tacrolimus based regimes. Twenty-seven subjects (12 males, 15 females) were studied as controls. Plasma adiponectin, high sensitive C reactive protein (hsCRP), Asymetric dimethyl arginine (ADMA) levels were studied before transplantation and on days 1, 3, 7, 14, and 28. The brachial artery flow mediated dilatation (FMD) was studied before transplantation and on the 28th day. RESULTS: Serum hsCRP and ADMA levels decreased significantly from the first posttransplantation day on each measurement (P<0.001 for all) while the decrement of plasma adiponectin started in the third day (P<0.001 for all). The FMD was lower in the patients than the control group (P<0.001) and improved significantly in the 28th day of transplantation (P<0.001). CONCLUSIONS: The results indicate that ADMA is associated with FMD in CKD both before and after kidney transplantation. Endothelial functions improve at the very beginning of the posttransplantation period with accompanying reduction in ADMA and hsCRP levels.

Adult↗

Assessment of oxidative stress in the early posttransplant period: comparison of cyclosporine A and tacrolimus-based regimens.

BACKGROUND: Oxidative stress is one of the leading causes of cardiovascular morbidity and mortality in chronic kidney disease. Although it is clear that many metabolic abnormalities improve, the effects of kidney transplantation on oxidative state are obscure. METHODS: Twenty-three kidney transplant patients were included in the study. Eleven patients (mean age 27.9+/- 9.1 years) were treated with cyclosporine A (CsA) whereas 12 patients (mean age 22.4 +/- 3.4 years) were treated with tacrolimus. Twenty-three healthy subjects served as controls. None of the patients or controls suffered from diabetes mellitus or an acute infection at the time of the study. Plasma malondialdehyde (MDA), plasma selenium (Se), erythrocyte glutathione peroxidase (GSH-Px), erythrocyte superoxide dismutase (SOD), erythrocyte Zn (EZn), and erythrocyte Cu (ECu) levels were studied before and in the 1st, 3rd, 7th, 14th and 28th days after the transplantation. RESULTS: The GSH-Px, SOD, ECu, EZn and selenium levels were lower and MDA levels were higher in patients than controls before transplantation (p < 0.001 for all). MDA levels decreased and SOD, GSH-Px, ECu, EZn levels increased in parallel to the decrement of serum creatinine levels following the renal transplantation. No difference was found among the patients regarding the treatment regime. CONCLUSION: The study data suggest that the improvement in oxidative state parameters begins at the first day of renal transplantation and continues at the 28th posttransplant day in living donor transplantations.

Adult↗

Blockade of the renin-angiotensin system increases plasma adiponectin levels in type-2 diabetic patients with proteinuria.

BACKGROUND/AIMS: Adiponectin seems to be an important modulator for metabolic and vascular diseases. A case study was designed to measure plasma adiponectin levels and to investigate the effects of angiotensin-converting enzyme inhibitors on adiponectin levels in type-2 diabetic patients with proteinuria. METHODS: Forty-nine patients (28 males, 21 females) and 23 healthy volunteers (13 males, 10 females) were included in the case study. Patients with proteinuria were treated with 5 mg/day ramipril (n = 21) for 4 weeks. RESULTS: Adiponectin levels of patients were significantly lower than those of healthy volunteers (p < 0.001). There were significant negative correlations between adiponectin concentrations and insulin levels as well as the homeostasis model assessment (HOMA) index in the patient group (r = -0.655, p < 0.001; r = -0.469, p = 0.001, respectively). There was also a significant negative correlation between plasma adiponectin concentrations and the degree of proteinuria (r = -0.912, p < 0.001). Plasma adiponectin levels in patients with proteinuria (n = 21; 4.81 +/- 3.17 microg/ml) were significantly lower than those without proteinuria (n = 28; 10.25 +/- 2.03 microg/ml; p < 0.001). After the treatment period, adiponectin levels significantly increased (p < 0.001) and proteinuria, plasma insulin, and HOMA indexes significantly decreased in the treatment group (p < 0.001, p < 0.001, p = 0.002, respectively). CONCLUSIONS: The results suggest that adiponectin is inversely correlated with proteinuria and treatment with ramipril both corrects proteinuria and increases the low adiponectin levels in diabetic patients.

Adiponectin↗

Peroxisome proliferator-activated receptor gamma (PPAR-gamma) agonist increases plasma adiponectin levels in type 2 diabetic patients with proteinuria.

Adiponectin appears to be an important modulator for metabolic and vascular diseases. A case-controlled study was designed to measure plasma adiponectin levels and investigate the effects of rosiglitazone on adiponectin levels in type 2 diabetic patients with proteinuria. Sixty-four patients (mean age, 46.1+/-4.6 yr; 30 male, 34 female) and 26 healthy volunteers (mean age, 45.3+/-4.8 yr; 14 male, 12 female) were included. Patients with proteinuria were treated with 4-mg/d rosiglitazone (n=21, 10 males, 11 females) for 4 wk. Adiponectin levels in patients were significantly lower than those of controls (p<0.001). There were significant negative correlations between adiponectin concentrations and insulin levels as well as homeostasis model assessment (HOMA) index in patient's group (r=- 0.538, p<0.001; r=- 0.393, p=0.001, respectively). There was also a significant negative correlation between plasma adiponectin concentrations and the degree of proteinuria (r=- 0.526, p=0.002). Plasma adiponectin levels in patients with proteinuria (n=31; 3.91+/-2.57 microg/mL) were significantly lower than those without proteinuria (n=33; 10.15+/-1.97 microg/mL) (p<0.001). After the treatment period, adiponectin levels significantly increased (p<0.001) and proteinuria, plasma insulin, and HOMA indexes significantly decreased in treatment group (p<0.001, p<0.001, p<0.001, respectively). The results suggest that adiponectin is inversely correlated with proteinuria and treatment with peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonist rosiglitazone both corrects proteinuria and increases the low adiponectin levels in diabetic patients.

Adipocytes↗

Colchicine-induced myopathy with myotonia in a patient with chronic renal failure.

Although colchicine induced myopathy has been described in patients with chronic renal failure, colchicine induced myopathy with myotonia has been reported very rarely. A 49-year-old man with chronic renal failure was hospitalised for investigation of fatigue, malaise and severe pain in all extremities. He was on colchicine therapy for 5 months. Neurological examination showed mildly decreased sensation in a distal symmetric pattern in lower extremities, moderate proximal limb weakness, hyporeflexia and severe myalgia on palpation. No clinical evidence of myotonia was present. Laboratory studies showed elevated creatine phosphokinase (CK), lactic dehydrogenase (LDH), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. Electromyographic (EMG) findings were compatible with myopathy and abundant, widespread myotonic discharges were determined. Muscle biopsy was consistent with vacuolar myopathy. After withdrawal of colchicine, CK, LDH, AST and ALT levels were normalised and the symptoms were disappeared gradually. In conclusion, the detection of myopathic motor unit potentials with myotonic discharges on EMG in patients on colchicine therapy is an important finding and it is possible to suggest that this clue may lead to the invasive procedure of muscle biopsy unnecessary.

Biopsy↗

Increased fasting plasma acylation-stimulating protein concentrations in nephrotic syndrome.

Acylation-stimulating protein (ASP) is an adipocyte-derived protein that has recently been suggested to play an important role in the regulation of lipoprotein metabolism and triglyceride (TG) storage. ASP also appears to have a role in the regulation of energy balance. In addition to its role as a hormonal regulator of body weight and energy expenditure, leptin is now implicated as a regulatory molecule in lipid metabolism. However, little is known about the alterations in fasting plasma ASP and leptin concentrations in the nephrotic syndrome. As hyperlipidemia is one of the most striking manifestations of the nephrotic syndrome, we have investigated fasting plasma ASP and leptin levels and their relation to lipid levels in this syndrome. Twenty-five patients with untreated nephrotic syndrome and 25 age-, sex-, and body mass index-matched healthy controls were included in the study. Fasting plasma lipoproteins, TG, total cholesterol, lipoprotein(a), apolipoprotein AI (apoAI), apoB, urinary protein, plasma albumin, third component of complement (C3), ASP, and leptin levels were measured in both groups. Total cholesterol, TG, low and very low density lipoproteins, lipoprotein(a), apoB, and urinary protein levels were increased in the patient group, whereas plasma albumin, high density lipoprotein cholesterol, and apoAI levels were decreased compared with those in the control group (P < 0.001). Plasma ASP levels were significantly higher in the patient group compared with the control subjects (133.72 +/- 65.14 vs. 29.93 +/- 12.68 nmol/liter; P < 0.001), whereas leptin (2.69 +/- 2.06 vs. 3.99 +/- 2.99 ng/ml; P = 0.118) and C3 (1.01 +/- 0.25 vs. 1.06 +/- 0.23 g/liter; P = 0.662) levels were not significantly different between the two groups. Plasma leptin levels were correlated with body mass index in both nephrotic patients (r(s) = 0.86; P < 0.001) and controls (r(s) = 0.98; P < 0.001), but were not correlated with the other parameters. Fasting ASP concentrations showed no correlation with body mass index, proteinuria, plasma albumin, leptin, or any lipid parameter in either group, but C3 levels (in patient group: r(s) = 0.92; P < 0.001; in control group: r(s) = 0.68; P < 0.001). Our findings showed that plasma ASP levels were significantly elevated, whereas leptin levels were normal in the nephrotic syndrome. Increased ASP levels in the setting of dyslipidemia in the nephrotic syndrome raise the possibility of an ASP receptor defect in adipocytes, which also suggests the existence of so-called ASP resistance. Moreover, it is possible that ASP activity is maximal, but cannot keep up with increased rates of lipid production by the liver. Thus, further studies are needed to elucidate the mechanism or source (adipocytes, the liver, or both) of elevated ASP concentrations in the nephrotic syndrome.

Adolescent↗

Timing of replacement therapy for acute renal failure after cardiac surgery.

OBJECTIVE: Acute renal failure (ARF) following cardiac surgery remains a significant cause of mortality. The aim of this study is to compare early and intensive use of continuous veno-venous hemodiafiltration (CVVHDF) with conservative usage of CVVHDF in patients with ARF after cardiac surgery. MATERIALS AND METHODS: Due to ARF, CVVHDF was required in two groups of a total of 61 adult patients (1.79% of all patients). Group 1 included 27 patients while Group 2 included 34 patients. CVVHDF was performed on Group 1 when creatinine level exceeded 5 mg/dL, or potassium level exceeded 5.5 mEq/L irrespective of the urine output. CVVHDF was performed on Group 2 when urine output was less than 100 mL within consecutive 8 hours, with no response to 50 mg furosemide with the supplementary criterion that urine sodium concentration should be >40 mEq/L before the administration of furosemide. RESULTS: The mean elapsed time between the surgery and the initiation of CVVHDF was 2.56 +/- 1.67 days in Group 1 and 0.88 +/- 0.33 days in Group 2 (p = 0.0001). The mean intensive care unit (ICU) stay for Group 1 was 12 +/- 3.44 days and 7.85 +/- 1.26 days for Group 2 (p = 0.0001). ICU mortality rate was 48.1% for Group 1 and 17.6% for Group 2 (p = 0.014). The overall hospital mortality rate was 55.5% for Group 1 and 23.5% for Group 2 (p = 0.016). CONCLUSION: Recognition of ARF and early beginning of the CVVHDF are extremely important. The sooner the ARF after surgery is recognized and CVVHDF is performed, the higher the likelihood of the reduction of the hospital mortality.

Acute Kidney Injury↗

Severe rhabdomyolysis due to malignant hyperthermia during renal transplantation procedure can cause delayed graft function.

A case of rhabdomyolysis from malignant hyperthermia occurred during renal transplantation surgery is presented. After the completion of vascular and uretherovesical anostomosis, the patient's heart rate began to rise, sweatiness was observed and body temperature increased to 41 degrees C. Additionally, metabolic and respiratory acidosis and hyperkalemia were detected. Serum creatine kinase and lactic dehydrogenase levels were increased significantly. After external cooling and the administration of dantrolene sodium, body temperature and heart rate were decreased. During this period; furosemide, mannitol and sodium bicarbonate were given. Three hours after the completion of surgery, urine output was begun and urine myoglobin was found to be positive. Renal function improved gradually and serum creatinine level decreased to 1.6 mg/dl on the 14th postoperative day. Malignant hyperthermia can lead to severe rhabdomyolysis and delayed graft function in renal transplant recipients. Early diagnosis and intervention is crucial for protecting renal function.

Adult↗