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Öğe The activities of serum adenosine deaminase and xanthine oxidase enzymes in Behcet's disease(Elsevier Science Bv, 2002) Sögüt, S; Aydin, E; Elyas, H; Aksoy, N; Özyurt, H; Totan, Y; Akyol, ÖBackground: Adenosine deaminase (AD) and xanthine oxidase (XO) are enzymes of purine catabolism that catalyze the conversion of adenosine to inosine, deoxyadenosine to deoxyinosine, hypoxanthine to xanthine and xanthine to Uric acid, respectively. AD is known to be an important enzyme in the maturation and function of T lymphocytes. The aim of this prospective study was to evaluate whether there are changes in serum AD activity as an index of T lymphocyte function in Behcet's disease (BD) which is known as having T cell-mediated immune response. Methods: A total of 32 patients and 26 sex- and age-matched healthy control subjects were analysed for AD and XO activities. The patients with BD were divided into two subgroups: BD with and without eye lesions. Twelve patients with complete BD and four patients with incomplete BD had eye complications. AD and XO activities in serum were measured with spectrophotometric methods. Re vults: There was a remarkable increase in AD activity and moderate increase in XO in patients with BD compared to controls indicating T cell activation and increased maturation. Serum AD activity of complete BD was higher than that of incomplete BD. There was no difference it) XO activity between the subgroups of BD. Significant positive correlation was found between AD and XO in BD, although there was no correlation in control group. Conclusions: The results indicate that increased AD and XO activities may provide an additional benefit for the diagnosis of BD and subtyping of the disease as having eye complication or not and complete and incomplete BD. Further studies are needed to bring to light the exact mechanism of AD and XO activity elevation. (C) 2002 Elsevier Science B.V. All rights reserved.Öğe Adenosine deaminase and xanthine oxidase activities in bladder washing fluid from patients with bladder cancer(Pergamon-Elsevier Science Ltd, 2003) Güleç, M; Akin, H; Yüce, H; Ergin, E; Elyas, H; Yalçin, O; Akyol, ÖActivities of adenosine deaminase (AD), and xanthine oxidase (XO) enzymes were measured in bladder washing fluid (BWF) from 37 patients with bladder cancer. The patients were divided into several groups according to their sex; pattern, number, and depth of the tumors; and tumor grade. There was a statistically significant difference in XO activities between the patients having no tumor and papillary tumor (p < 0.002). The differences in XO values between the patients having no tumor and single tumor; and with no tumor and multiple tumors were statistically significant (p < 0.012, p < 0.016 respectively). XO activities were increased in patients with both papillary and multiple tumors compared to tumor-free group. Regarding to the depth of tumors, only the differences in XO values between the patients having no tumor and superficial tumor was statistically significant (p < 0.037). XO values of patients in grade 1 were higher than the patients having no tumor (p < 0.010). AD activities in patients with multiple and invasive tumor were increased compared to patients with single and superficial tumor. AD values in grade 3 were lower than grade 2. However, we did not find any statistically significant differences in AD activities in all groups. As a conclusion, increased XO activity in BWF might be a potentially important finding as an additional diagnostic biochemical tool for bladder cancer. But we could not say this for AD activity. Further investigations in a larger cohort of patients with bladder cancer are needed to enlighten the possible diagnostic role of XO and AD in BWF. (C) 2003 The Canadian Society of Clinical Chemists. All rights reserved.Öğe Caffeic acid phenethyl ester changes the indices of oxidative stress in serum of rats with renal ischaemia-reperfusion injury(Wiley, 2001) Özyurt, H; Irmak, MK; Akyol, Ö; Sögüt, SOxygen-derived free radicals have been implicated in the pathogenesis of renal injury after ischaemia-reperfusion. Caffeic acid phencthyl ester (CAPE), an active component of propolis extract, exhibits antioxidant properties. To investigate whether treatment with either CAPE or alpha-tocopherol modifies the levels of the endogenous indices of oxidant stress, we examined their effects on an in vivo model of renal ischaemia-reperfusion injury in rats. CA-PE at 10 mu mol kg(-1) or alpha-tocopherol at 10 mg kg(-1) was administered intraperitoneally before reperfusion. Acute administration of both CAPE and alpha-tocopherol altered the indices of oxidative stress differently in renal ischaemia-reperfusion injury. Copyright (C) 2001 John Wiley & Sons, Ltd.Öğe Caffeic acid phenethyl ester prevents intestinal reperfusion injury in rats(W B Saunders Co-Elsevier Inc, 1999) Koltuksuz, U; Özen, S; Uz, E; Aydinç, M; Karaman, A; Gültek, A; Akyol, ÖBackground/Purpose: Ischemia-reperfusion injury is encountered frequently in conditions that diminish intestinal blood flow. Caffeic acid phenethyl ester (CAPE), which is a specific component of the honeybee hive product propolis, exhibits potential antioxidant: properties. This experimental study was designed to determine the effect of CAFE on ischemia-reperfusion injury in rat intestine. Methods: Fifty rats were divided into 5 groups: sham (SH), saline ischemia (SI), saline reperfusion (SR), CARE ischemia (CI), and CARE reperfusion (CR). Either CAFE, 10 mu mol/kg, or saline was administered intraperitoneally 30 minutes before ischemia. Intestinal ischemia for 30 minutes and reperfusion for 60 minutes were applied. Ileum specimens were obtained to determine the tissue levels of malondialdehyde, superoxide dismutase, catalase, and histological changes. Results Malondialdehyde levels in the CR group did not increase after reperfusion when compared with the CI group. However, statistically significant differences were observed between the SR and SI groups. Additional mucosal injury in the CR group when compared with the CI group was not observed. Whereas, there was a statistically significant increase in mucosal injury in the SR group. Reperfusion did not cause further injuries through both biochemical and histological parameters in the CR group. Conclusions: Results of this study showed that prophylactic administration of CAFE in ischemic condition prevents reperfusion injuries by eliminating oxygen radicals and inhibiting polymorphonuclear leukocyte infiltration. CARE may be useful in combating the diseases of oxidative stress. J Pediatr Surg 34:1458-1462. Copyright (C) 1999 by W.B. Saunders Company.Öğe The comparison of nail and serum trace elements in patients with epilepsy and healthy subjects(Pergamon-Elsevier Science Ltd, 2004) Ilhan, A; Özerol, E; Güleç, M; Isik, B; Ilhan, N; Ilhan, N; Akyol, ÖThe objective of this prospective study was to determine the levels of manganese (Mn), copper (Cu), and zinc (Zn) levels in both nail and serum from patients with epilepsy. For this purpose, levels of these elements were measured in 31 patients with epilepsy and 19 healthy subjects. Element analyses were carried out by atomic absorption spectrophotometer (AAS). Increased Mn levels were detected in nail of patients with epilepsy compared to healthy controls (P<.008). The main nail Zn and Cu levels were found to be unchanged in epileptic patients compared to control subjects. There were no significant differences in serum Mn and Zn levels between epileptic patients and control subjects. However, there was a statistically significant increase in serum Cu levels in patients with epilepsy in comparison with control group (P<.009). Our results demonstrate that some trace element levels may vary in epileptic patients, and because of the more stable status, the analysis of these element levels in some tissues such as nail might be superior to serum analysis. (C) 2003 Elsevier Inc. All rights reserved.Öğe Comparison of serum nitric oxide, malondialdehyde levels, and antioxidant enzyme activities in Behcet's disease with and without ocular disease(Karger, 2004) Aydin, E; Sögüt , S; Özyurt, H; Özugurlu, F; Akyol, ÖObjective: The pathogenesis of Behcet's disease ( BD) may be related to excessive production of reactive oxygen species, activated neutrophils, and T lymphocytes. The goal of this prospective study was to investigate whether there is any relationship among the oxidant/ antioxidant system and nitric oxide ( NO) and malondialdehyde (MDA) levels in patients with BD and its subtypes: complete Behcet's disease (CBD) and incomplete Behcet's disease (ICBD), with or without ocular disease. Methods: Thirty-two patients and 26 age- and sex-matched healthy control subjects were evaluated for NO and MDA levels and antioxidant enzyme activities. The patients with BD were divided into two subgroups: those with and without ocular disease. Twelve patients with CBD and 4 patients with ICBD had ocular disease. The serum NO level was determined by Griess reaction. The MDA level was detected by thiobarbituric acid reaction. Superoxide dismutase ( SOD) and glutathione peroxidase (GSH-Px) activities in serum were analyzed with spectrophotometric methods. Results: Increased MDA levels but decreased GSH-Px activities in plasma were observed in BD patients with all subtypes, as compared with controls. Concerning the presence of ocular disease and the subtype ( CBD or ICBD) compared with each other, there were no significant differences in MDA or NO serum levels and SOD or GSH-Px enzyme activities. Conclusions: Serum NO levels and SOD enzyme activities were not significantly changed in patients with BD and its subtypes; however, a remarkable decrease of GSH-Px enzyme activity and increase of MDA levels were found. Copyright (C) 2004 S. Karger AG, Basel.Öğe Concentrations of copper, zinc and various elements in serum of patients with bronchial asthma(Gustav Fischer Verlag, 2000) Vural, H; Uzun, K; Uz, E; Koçyigit, A; Çigli, A; Akyol, ÖIn this study, serum copper, zinc, magnesium, iron and calcium concentrations were investigated in 40 patients with bronchial asthma (BA) and in 43 healthy subjects. Copper and calcium levels were found to be increased in patients with BA compared to the control group (p<0.001 and p<0.001 respectively). On the other hand, the serum zinc level was significantly lower in healthy subjects (p<0.01). No changes were found in serum magnesium and iron levels in patients with BA compared to controls. In addition to various elements, certain serum proteins such as albumin, transferrin and ferritin were also assessed to determine whether there was a relationship between the elements and proteins in patients with BA. There was only a significant decrease in albumin concentration in patients with BA (p<0.05).Öğe Determination of copper, zinc and manganese in nail and serum from patients with migraine(Dustri-Verlag Dr Karl Feistle, 2003) Özerol, E; Ulvi, H; Ilhan, N; Güleç, M; Ilhan, A; Akyol, ÖMetallo-enzymes contain trace elements in their molecular structure to be metabolically active. Manganese-superoxide dismutase (Mn SOD) contains Mn and copper, zinc-superoxide dismutase (Cu, Zn SOD) contains Cu. and Zn as prosthetic groups. There have been some studies on the oxidant/anti oxidant status of patients with migraine. In the present study, the levels of copper, zinc and manganese in nail and serum were investigated in 53 patients with migraine and 19 healthy subjects. Copper, Zn and Mn levels were measured by atomic absorption spectrophotometry and results obtained were statistically compared. The concentration of Mn in nail and serum was significantly higher in migraine patients than those of control subjects. Although Zn and Cu concentrations in nail were increased in migraine group compared to control group, the difference was not statistically significant. There was a statistically significant increase in Cu level (p < 0.02) and decrease in Zn level in serum from patients with migraine compared to those of control group. The unchanged or increased levels of trace elements, which play important roles as prosthetic groups in SOD, in both nail and serum may suggest that the antioxidant enzyme activities are not negatively affected from the changes. The results obtained are discussed in the light of the literature on the relationship between migraine and trace elements plus antioxidant systems.Öğe The effect of caffeic acid phenethyl ester on ischemia-reperfusion injury in comparison with ?-tocopherol in rat kidneys(Springer-Verlag, 2001) Irmak, MK; Koltuksuz, U; Kutlu, NO; Yagmurca, M; Özyurt, H; Karaman, A; Akyol, ÖOxygen-derived free radicals have been implicated in the pathogenesis of renal injury after ischemia-reperfusion. Caffeic acid phenethyl ester (CAPE), an active component of propolis extract, exhibits antioxidant and anti-inflammatory properties. To determine whether CAPE offers any advantage over alpha -tocopherol, we compared their effects on an in vivo model of renal ischemia-reperfusion injury in rats. CAFE at 10 mu mol/kg or alpha -tocopherol at 10 mg/kg was administered intraperitoneally before reperfusion. Acute administration of CAFE suppressed ischemia-reperfusion induced renal lipid peroxidation and tissue injury more than alpha -tocopherol. CAFE may therefore offer a therapeutic advantage in acute injury settings.Öğe Effects of electromagnetic radiation from a cellular telephone on the oxidant and antioxidant levels in rabbits(Wiley, 2002) Irmak, MK; Fadilloglu, E; Güleç, M; Erdogan, H; Yagmurca, M; Akyol, ÖThe number of reports on the effects induced by electromagnetic radiation (EMR) in various cellular systems is still increasing. Until now no satisfactory mechanism has been proposed to explain the biological effects of this radiation. Oxygen free radicals may play a role in mechanisms of adverse effects of EMR. This study was undertaken to investigate the influence of electromagnetic radiation of a digital GSM mobile telephone (900 MHz) on oxidant and antioxidant levels in rabbits. Adenosine deaminase, xanthine oxidase, catalase, myeloperoxidase, superoxide dismutase (SOD) and glutathione peroxidase activities as well as nitric oxide (NO) and malondialdehyde levels were measured in sera and brains of EMR-exposed and sham-exposed rabbits. Serum SOD activity increased, and serum NO levels decreased in EMR-exposed animals compared to the sham group. Other parameters were not changed in either group. This finding may indicate the possible role of increased oxidative stress in the pathophysiology of adverse effect of EMR. Decreased NO levels may also suggest a probable role of NO in the adverse effect. Copyright (C) 2002 John Wiley Sons, Ltd.Öğe Evidence that the activities of erythrocyte free radical scavenging enzymes and the products of lipid peroxidation ape increased in different forms of schizophrenia(Springernature, 2001) Herken, H; Uz, E; Özyurt, H; Sögüt, S; Virit, O; Akyol, ÖIn order to examine antioxidant status and lipid peroxidation in schizophrenia patients, activities of three free radical scavenging enzymes (superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT)), and the level of thiobarbituric acid-reactive substances (TBARS) as an index of lipid peroxidation have been studied in red blood cells. Schizophrenic patients were divided into three groups (disorganized (n = 21), paranoid (n = 26) and residual types (n = 18)) to determine differences between subgroups. SOD, CAT and GSH-Px activities in the control group were found to be 1461.0 +/- 248.6 U g(-1) Hb, 148.2 +/- 59.3 k g(-1) Hb and 25.87 +/- 4.25 U g(-1) Hb, respectively. We found no significant differences in SOD activities between study and control groups. There was a significant increase in SOD activity in the residual group compared to the paranoid group (P < 0.005). CAT activity was found to be increased in disorganized (148%), paranoid (147%), and residual (165%) groups compared to the control group. GSH-Px activity was markedly increased in the study groups except the paranoid group. Statistically significant (3-4 fold) increases in TBARS levels of red blood cells were found in all the study groups. It is proposed that antioxidant status may be changed in schizophrenia and thus may induce lipid peroxidation. Therefore, oxidative stress may have a pathophysiological role in all the subtypes of schizophrenia.Öğe Hair lead and cadmium concentrations in patients with epilepsy and migraine(Wiley, 2003) Sasmaz, S; Uz, E; Pinar, T; Vural, H; Eiri, M; Ilhan, A; Akyol, ÖEpilepsy and migraine are neurological manifestations of neurocutaneous diseases. The studies that investigate the etiology of these manifestations may illuminate the physiopathological bases of neurocutaneous disorders. The hypothesis that the elevation of toxic trace element concentration in the brain is an important triggering factor for seizures and subsequent neuronal damage in epilepsy and migraine was investigated in this clinical prospective study. The levels of two heavy metals (lead [Pb] and cadmium [Cd]) in scalp hair were measured in patients with epilepsy (n=33) and migraine (n=40) as well as healthy control subjects (n=26). The hair concentration of these two toxic trace elements was determined by atomic absorption spectrophotometry. There was a significant increase in Pb concentration in epilepsy group when compared to both control (p<0.006) and migraine group (p<0.02). There was no difference in mean Cd concentration of hair from epilepsy, migraine patients and control groups. Therefore, no conclusive findings were obtained for Cd. Elevated Pb content in epileptic patients was accepted as being of particular importance. Our findings support the hypothesis that the elevation in Pb concentration in the scalp hair amongst patients with epilepsy may show the elevation in the brain and constitute an important triggering factor for seizures.Öğe The indices of endogenous oxidative and antioxidative processes in plasma from schizophrenic patients The possible role of oxidant/antioxidant imbalance(Pergamon-Elsevier Science Ltd, 2002) Akyol, Ö; Herken, H; Uz, E; Fadillioglu, E; Ünal, S; Sögüt, S; Özyurt, HThere is great evidence in recent years that oxygen free radicals play an important role in the pathophysiology of schizophrenia. The present study was performed to assess the changes in plasma nitric oxide (NO) and thiobarbituric acid-reactive substances (TBARS) levels, and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and xanthine oxidase (XO) activities in schizophrenic patients compared to age- and sex-matched normal controls. A hundred patients with schizophrenia and 51 healthy volunteers were included in the study. XO, SOD, and GSH-Px activities as well as NO and TBARS levels were estimated by standard biochemical techniques in the plasma of normal healthy controls and schizophrenia patients. In schizophrenia, increased plasma XO activity (P<.0001) and NO levels (P<.0001), decreased SOD activity (P<.0001), and unchanged GSH-Px activity were detected compared to control group. Plasma TBARS levels were increased in schizophrenic patients (P<.01), especially in the residual subtype. TBARS levels in nonsmoker schizophrenic patients were found to be higher than nonsmoker controls. Although TBARS levels in both patients and controls were found to be higher in smokers as compared to nonsmokers, it was not statistically significant. No effects of duration of the illness, gender, and low and high dose of daily neuroleptic treatment equivalent to chlorpromazine on oxidant and antioxidant parameters were observed. Because the dose and the duration of treatment with drugs have no influence on the results, it can be interpreted that the findings are more likely to be related mainly to the underlying disease. These findings indicated a possible role of increased oxidative stress and diminished enzymatic antioxidants, both of which may be relevant to the pathophysiology of schizophrenia. On the other hand, increased NO production by nitric oxide synthetases (NOSs) suggests a possible role of NO in the pathophysiological process of schizophrenia. These findings may also suggest some clues for the new treatment strategies with antioxidants and NO synthase (NOS) inhibitors in schizophrenia. (C) 2002 Elsevier Science Inc. All rights reserved.Öğe Malondialdehyde level and total superoxide dismutase activity in seminal fluid from patients with varicocele(Springer-Verlag, 2001) Akyol, Ö; Özbek, E; Uz, E; Koçak, I[Abstract Not Available]Öğe Maternal serum and amniotic fluid hydroxyproline levels in neural tube defects(Karger, 2003) Özyurt, H; Totan, A; Sahin, S; Kilinç, C; Sögüt, S; Akyol, ÖObjective: The present study was aimed to evaluate the alterations of maternal serum and amniotic fluid OH-proline levels in neural tube defects (NTD). Methods: 38 patients and 23 control subjects were selected from the patients followed up by the Departments of Genetics and Antenatal Care, Zekai Tahir Burak Women's Health, Education and Research Hospital. Amnion fluid and blood samples were synchronously obtained from NTD and control subjects. OH-proline levels were detected spectrophotometrically. Results: Amniotic fluid CH-proline levels were found to be increased in NTID patients compared to control subjects (p < 0.05). There was no statistically significant difference in serum OH-proline levels between the groups. Conclusion: The results showed an increase in amniotic fluid OH-proline levels in NTD compared to the control group. It may be suggested that the increased OH-proline levels reflect increased collagen turnover in NTD patients. Indeed, amniotic fluid OH-proline levels may be a candidate as an additional diagnostic parameter in NTD. Copyright (C) 2003 S. Karger AG, Basel.Öğe Plasma malondialdehyde and nitric oxide levels in age related macular degeneration(British Med Journal Publ Group, 2001) Totan, Y; Çekiç, O; Borazan, M; Uz, E; Sögüt, S; Akyol, ÖAims-To evaluate alteration of plasma malondialdehyde (MDA) and nitric oxide (NO) levels in patients with exudative age related macular degeneration (ARMD). Methods-Plasma. nitrite plus nitrate concentrations as an index of plasma NO levels and plasma MDA level as a marker of lipid peroxidation were measured in patients with exudative ARMD and age and sex matched healthy subjects. Results-Significantly higher MDA and lower NO levels were detected in plasma of patients with ARMD compared with their controls (p=0.01, p=0.001, respectively). Conclusion-The results may support involvement of oxidative damage and vascular theory in the pathogenesis of ARMD as part of the ageing process.Öğe Plasma superoxide dismutase activity and malondialdehyde level correlate with the extent of acute appendicitis(Springer-Verlag, 2000) Koltuksuz, U; Uz, E; Özen, S; Aydinc, M; Karaman, A; Akyol, ÖAlthough the mechanism of acute appendicitis (AA) is partly understood, the progression following the onset of inflammation has not yet been clarified. To determine oxidative activities in the plasma of patients with AA, superoxide dismutase (SOD) activities and malondialdehyde (MDA) levels were measured in samples from 31 patients diagnosed as having AA and 10 otherwise healthy children with inguinal pathologies. The patients with AA were divided into three subgroups: acute focal (AFA) (n = 8), acute suppurative (ASA) (n = 9), and acute perforated appendicitis (APA) (n = 14), according to the intraoperative findings and histopathologic examination.. SOD and MDA were compared statistically between these subgroups and between them and the control group. Additionally, mean leukocyte counts of each group were determined and the differences between the groups were evaluated. Both SOD and MDA were significantly higher in the ASA and APA groups compared to controls and AFA group. The mean leukocyte numbers of the ASA and APA groups were significantly higher compared to the AFA group. Based to these results, it may be speculated that oxygen free radicals (OFR) may play an important role in the extent of AA. To prevent the hazardous effects of OFR, the organism may increase SOD and other antioxidant enzyme levels and/or activities.Öğe The protective role of caffeic acid phenethyl ester (CAPE) on testicular tissue after testicular torsion and detorsion(Springer, 2002) Uz, E; Sögüt, S; Sahin, S; Var, A; Özyurt, H; Güleç, M; Akyol, ÖTesticular artery occlusion causes an enhanced formation of reactive oxygen species, which contributes to the pathophysiology of tissue damage. Here, we have investigated the effects of caffeic acid phenethyl ester (CAPE), a new antioxidant and antiinflammatory agent, in rats subjected to testicular torsion/detorsion (T/D). Thirty-five male rats were divided into four groups: sham operation group (n = 8), torsion group (n = 9), T/ D + saline group (n = 9) and T/D + CAPE group (n = 9). Rats, except the sham operation group, were subjected to left unilateral torsion (720degrees rotation in the clockwise direction) without including the epididymis. After torsion (2 h) and detorsion (4 h) periods, rats were sacrificed and bilateral orchidectomy was performed. Testis tissues were washed with cold saline solution, cut into small pieces with scissors, placed into glass bottles and homogenised in four volumes of ice-cold Tris-HCl buffer. Clear supernatant fluid was used for biochemical analyses. Treating rats with CAPE (applied at 10 mumol/kg, 30 min prior to T/D) attenuated the testicular injury, as well as the increase in the tissue levels of myeloperoxidase and thiobarbituric acid-reactant substances (TBARS) caused by T/D in the testis. Testis tissues showed a significant increase in glutathione peroxidase (GSH-Px) activity compared to the torsion group when CAPE was applied. Taken together, our results clearly demonstrate that CAPE treatment exerts a protective effect on testicular T/D, and part of this effect may be due to inhibiting the neutrophil-mediated cellular injury.Öğe Red blood cell nitric oxide levels in patients with schizophrenia(Elsevier Science Bv, 2001) Herken, H; Uz, E; Özyurt, H; Akyol, Ö[Abstract Not Available]Öğe The relationships between plasma and erythrocyte antioxidant enzymes and lipid peroxidation in patients with rheumatoid arthritis(Elsevier France-Editions Scientifiques Medicales Elsevier, 2001) Akyol, Ö; Isçi, N; Temel, I; Özgöçmen, S; Uz, E; Murat, M; Büyükberber, SObjective. The present study was undertaken to evaluate the activities of some key erythrocyte and plasma enzymes participating in free radical metabolism and the end product of lipid peroxidation in rheumatoid arthritis, and whether there are any differences for these parameters between newly diagnosed untreated patients and rheumatoid arthritis patients on drug therapy. Patients and methods. Superoxide dismutase and catalase activities, and malondialdehyde levels were determined in erythrocytes and plasma samples from 54 patients with rheumatoid arthritis (21 of whom without any treatment and 33 on classical therapy regimens) and from 33 healthy controls. Results. There were no statistically significant differences in mean values of activities of the erythrocyte enzymes between the patients and controls. Malondialdehyde levels were significantly increased in both newly diagnosed untreated patients and patients on drug therapy compared to control subjects. Malondialdehyde levels were lower in the treated group than the newly diagnosed untreated group (0.214 +/- 0.111 mu mol/L and 0.388 +/- 0.075 mu mol/L, respectively) (P < 0.0001). Mean plasma superoxide dismutase activity was lower in the group of newly diagnosed untreated patients compared to those of the treated and control groups (1.31 +/- 0.69 U/mL, 1.79 +/- 0.94 U/mL and 2.48 +/- 0.95 U/mL, respectively) (P < 0.0001, untreated vs control groups). Conclusions. These results suggest sufficient antioxidant enzyme activities in erythrocytes in patients with rheumatoid arthritis and also increased lipid peroxidation end products in newly diagnosed untreated patients compared to control group and patients on drug therapy. (C) 2001 Editions scientifiques et medicales Elsevier SAS.