Nuri Bakan

Serum Oxidant/Antioxidant Status of Patients with Systemic Lupus Erythematosus

Abstract The levels of malondialdehyde and ceruloplasmin, and superoxide dismutase activity were higher, while transferrin concentration and the activities of glutathione peroxidase and catalase were lower in serum of patients with systemic lupus erythematosus (n=24) compared with healthy controls (n=20). Disease activity index correlated positively with serum malondialdehyde level (r=0.47, p<0.05), erythrocyte sedimentation rate (r=0.41, p<0.05) and C-reactive protein concentration (r=0.41, p<0.05), while it correlated negatively with serum superoxide dismutase (r=0.42, p<0.05) and glutathione peroxidase (r= −0.44, p<0.05) activities in patients. No such correlations were found in healthy control subjects. It remains to be seen whether correlations found between disease activity score and serum malondialdehyde level, and also activities of serum superoxide dismutase and glutathione peroxidase enzymes observed in the present study may be used to predict prognosis in patients with systemic lupus erythematosus.

The Effect of Melatonin against Oxidative Damage during Total-Body Irradiation in Rats

Abstract Koc, M., Taysi, S., Buyukokuroglu, M. E. and Bakan, N. The Effect of Melatonin against Oxidative Damage during Total-Body Irradiation in Rats. Radiat. Res. 160, 251–255 (2003). Melatonin has been reported to participate in the regulation of a number of important physiological and pathological processes. Melatonin, which is a powerful endogenous antioxidant, may play a role in the prevention of oxidative damage. The aim of this study was to investigate the effect of pretreatment with melatonin (5 mg kg–1 and 10 mg kg–1) on γ-radiation-induced oxidative damage in plasma and erythrocytes after total-body irradiation with a single dose of 5 Gy. Total-body irradiation resulted in a significant increase in plasma and erythrocyte MDA levels. Melatonin alone increased the levels of SOD and GSH-Px. Erythrocyte and plasma MDA levels in irradiated rats that were pretreated with melatonin (5 or 10 mg kg–1) were significantly lower than those in rats that were not pretreated. There was no significant difference between the effects of 5 and 10 mg kg–1 on plasma MDA activities and CAT activities. However, erythrocyte MDA levels showed a dose-dependent decrease, while GSH-Px activities increased with dose. Our study suggests that melatonin administered prior to irradiation may protect against the damage produced by radiation by the up-regulation of antioxidant enzymes and by scavenging free radicals generated by ionizing radiation.

Fecal calprotectin concentration in celiac disease.

Goals We aimed to determine fecal calprotectin (FC) concentration and its relation with histopathologic findings of children with celiac disease (CD) and to observe the probable alterations under gluten-free diet (GFD). Background As FC is regarded as a marker of inflammation in the gastrointestinal tract, we hypothesized that it might be increased in untreated CD. Study The study included 29 newly diagnosed patients with CD (mean age: 6.6±0.6 y) and sex and age-matched 10 healthy children. All of the children with CD admitted to the hospital were classical form who has chronic diarrhea and failure to thrive. The degree of mucosal damage was graded according to the modified Marsh criteria. FC concentration was determined by enzyme-linked immunosorbent assay method on admission and after 1 year of GFD. Results Mean FC concentration of children with CD on admission and of healthy children were 13.40±8.5 and 4.3±3.3 mg/L, respectively (P=0.004). FC concentration under GFD was 4.6±2.7 mg/L and there was a significant statistical difference between untreated patients and those under GFD for 1 year (P=0.001). There was no statistical difference between FC concentration of those under GFD and healthy children (P=0.8). Mean FC concentrations of children with total-villous atrophy and partial-villous atrophy were significantly different (13.8±9.3 mg/L vs. 3.7±1.8 mg/L, P=0.005). Conclusions It was found that FC concentration is increased in childhood CD, related to the severity of histopathologic findings and responsive to GFD. The pathogenetic mechanism by which FC is increased in CD should be investigated in further studies.

Effects of Oral Ginkgo biloba Supplementation on Cataract Formation and Oxidative Stress Occurring in Lenses of Rats Exposed to Total Cranium Radiotherapy

PurposeTo determine the antioxidant role of Ginkgo biloba (GB) in preventing radiation-induced cataracts in the lens after total-cranium irradiation of rats with a single radiation dose of 5 Gy.MethodsSprague-Dawley rats were randomly divided into three groups. Group 1 received neither GB nor irradiation (control group). Group 2 was exposed to total-cranium irradiation of 5 Gy in a single dose [radiation therapy (RT) Group], and group 3 received total cranium irradiation from a cobalt-60 teletherapy unit, plus 40 mg/kg per day GB (RT+GB group). At the end of the tenth day, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the lipid peroxidation level [malondialdehyde (MDA)].ResultsIrradiation significantly increased both the MDA level and the activity of GSH-Px, and significantly decreased the activity of SOD in the rat lenses. GB supplementation significantly increased the activities of SOD and GSH-Px enzymes and significantly decreased the MDA level. Total cranium irradiation of 5 Gy in a single dose promoted cataract formation, and GB supplementation protected the lenses from radiation-induced cataracts.ConclusionsWe suggest that Ginkgo biloba is an antioxidant that protects the rat lens from radiation-induced cataracts.

Antioxidant Potential and Transferrin, Ceruloplasmin, and Lipid Peroxidation Levels in Women with Preeclampsia

Background The aim of this study was to evaluate lipid peroxidation and antioxidant function in patients with preeclampsia and in normotensive pregnant women and to assess an association with the severity of the disease. Methods Twenty-one patients with mild preeclampsia, 15 patients with severe preeclampsia, and 19 normotensive pregnant women were included in the study. Plasma antioxidant potential (AOP) status, ceruloplasmin (Cp) and transferrin (Trf) levels as antioxidants, and malondialdehyde (MDA) levels as an indicator of lipid peroxidation were measured. Results Whereas the AOP and Trf levels of the severe and mild preeclampsia groups were found to be reduced, the MDA and Cp levels were increased compared with those of the normotensive pregnant group. There were statistically significant negative correlations between AOP and MDA in all groups. No differences were observed between the groups with severe and mild preeclampsia with respect to these analytes. Conclusion Our findings suggest that lipid peroxidation may be an important factor in the pathogenesis of preeclampsia and that plasma antioxidants and oxidants are altered in preeclampsia. However, these findings may not be useful in distinguishing women with severe and mild preeclampsia.

The effects of oral zinc sulphate during radiotherapy on anti‐oxidant enzyme activities in patients with head and neck cancer: A prospective, randomised, placebo‐controlled study

The purpose was to determine the effects of oral zinc sulphate along with radiotherapy on anti‐oxidant enzyme activities in patients with head and neck cancer. Thirty patients with head and neck cancer were randomly assigned to receive either zinc sulphate capsules (including 50 mg zinc) (n = 15) or placebo (n = 15) three times a day, starting on the day of the first radiotherapy fraction and continuing throughout the scheduled radiotherapy course including weekends and 6 weeks after radiotherapy. The patients were treated with telecobalt radiation at conventional fractionation of 2 Gy/fraction and five fractions/week in 20–35 fractions for a period of 4–7 weeks. Blood samples for biochemical parameters were collected after an overnight fast (12 h) before radiotherapy, the first day and 6 weeks after radiotherapy. In the placebo group, three patients were excluded. No difference was detected in any final measurement activities of erythrocyte anti‐oxidant enzyme such as copper‐zinc superoxide dismutase (Cu‐Zn SOD), catalase (CAT) and glutathione peroxidase (GSH‐Px) in the direct comparison between the zinc sulphate and the placebo group, except erythrocyte SOD activities measured the first day after radiotherapy (p < 0.03). In therespective measurement analysis of the groups in themselves, in the zinc sulphate group, while the statistical analysis for the activities of erythrocyte CAT and GSH‐Px were significantly different (χ2 = 12.4, p < 0.05; χ2 = 8.9, p < 0.05, respectively) before radiotherapy, the first day and 6 weeks after radiotherapy, the activities of SOD did not differ (χ2 = 4.2, p > 0.05). In these three measurements, there was no statistical significance in the activities of enzymes in erythrocyte Cu‐Zn SOD, CAT and GSH‐Px in the placebo group. Before radiotherapy, plasma zinc levels were normal in 16 patients (59.2%) and were lower in 11 patients (40.8%) compared with laboratory levels. It would be worthwhile studying the effect of oral zinc sulphate supplements to improve the anti‐oxidant enzyme activity in radiation‐treated cancer patients, in the hope of reducing radiation‐induced toxicity.

Glycosylation of nail in diabetics: possible marker of long-term hyperglycemia

Fingernail samples from 32 patients with diabetes mellitus and from 26 non-diabetics were analyzed in order to determine the protein glycosylation rate in nail. Nail glycosylation was assayed by the thiobarbituric acid reaction. Blood was taken from both diabetics and non-diabetics at the same time for measurement of hemoglobin glycosylation. In non-diabetics, the protein glycosylation in nail and glycosylated hemoglobin were found to be 8.35 +/- 2.7 nmol fructosamine/mg nail and 2.24 +/- 0.45 mumol fructosamine/g hemoglobin, respectively. In diabetics, however, there was an extremely high glycosylation in both nail protein and hemoglobin: 16.0 +/- 7.35 nmol fructosamine/mg nail and 5.17 +/- 1.17 mumol fructosamine/g hemoglobin (p less than 0.001 for both). A significant correlation was found between nail glycosylation and glycosylated hemoglobin in diabetics (r = 0.923, p less than 0.001). Also, there was a correlation between diabetic fasting blood glucose and protein glycosylation in nail (r = 0.947, p less than 0.001). Our findings show that it might be useful in the investigation of microvascular complications of diabetes mellitus to evaluate the possibility of nail glycosylation providing a stable long-term measure of tissue glycosylation.

Effects of Some Antibiotics on Human Erythrocyte 6-Phosphogluconate Dehydrogenase: An in vitro and in vivo Study

The in vitro and in vivo effects of some antibiotics on human erythrocyte 6-phosphogluconate dehydrogenase were investigated. Human erythrocyte 6-phosphogluconate dehydrogenase was purified with ammonium sulphate precipitation, 2′,5′ ADP-Sepharose 4B affinity and gel filtration chromatography. Some antibiotics (netilmicin sulphate, cefepime, amikacin, isepamycin, chloramphenicol, ceftazidim, teicoplanin, ampicillin, ofloxacin, levofloxacin, cefotaxime, penicillin G, gentamicin sulphate, ciprofloxacin) inhibited enzyme activity in vitro but others (cefozin, decefin, streptomycin, combisid, and meronem) were devoid of inhibitory effects. For the drugs having low IC50 values (netilmicin sulphate and cefepime), in vivo studies were performed in rats. Netilmicin sulphate at 15-mg/kg inhibited enzyme activity significantly (p < 0.001) 1h, 2h, and 3h after dosing and cefepime at 200-mg/kg very significantly (p < 0.001) inhibited the enzyme 1 h and 2 h after dosing. Netilmicin sulphate and cefepime inhibited rat erythrocyte 6-phosphogluconate dehydrogenase both in vivo and in-vitro.

Trace elements and disease activity score in patients with rheumatoid arthritis

AbstractIn this study, we aimed to investigate the levels of serum Zn, Cu, Mg, Mn, and Fe in rheumatoid arthritis and whether they are related to the severity of the disease. The sera from 29 patients with rheumatoid arthritis were studied and compared with those from healthy controls (n = 22). Although serum Fe, Mg and Mn levels were lower in the rheumatoid arthritis group than in the control group, the difference was not statistically significant. Significantly higher Cu (p < 0.001) and lower Zn serum levels (p < 0.012) were found in rheumatoid arthritis than in controls.A statistically significant positive correlation was present between Cu levels and disease activity score (DAS), and there was a negative correlation between Zn levels and DAS.We think that alterations of the level of some trace elements in rheumatoid arthritis are a consequence of and not one of the causes of the disease, as in many other chronic inflammatory disorders.

Comparison of Cobas 6500 and Iris IQ200 fully-automated urine analyzers to manual urine microscopy.

Introduction Urine screening is achieved by either automated or manual microscopic analysis. The aim of the study was to compare Cobas 6500 and Iris IQ200 urine analyzers, and manual urine microscopic analysis. Materials and methods A total of 540 urine samples sent to the laboratory for chemical and sediment analysis were analyzed on Cobas 6500 and Iris IQ200 within 1 hour from sampling. One hundred and fifty three samples were found to have pathological sediment results and were subjected to manual microscopic analysis performed by laboratory staff blinded to the study. Spearman’s and Gamma statistics were used for correlation analyses, and the McNemar test for the comparison of the two automated analyzers. Results The comparison of Cobas u701 to the manual method yielded the following regression equations: y = - 0.12 (95% CI: - 1.09 to 0.67) + 0.78 (95% CI: 0.65 to 0.95) x for WBC and y = 0.06 (95% CI: - 0.09 to 0.25) + 0.66 (95% CI: 0.57 to 0.73) x for RBC. The comparison of IQ200 Elite to manual method the following equations: y = 0.03 (95% CI: - 1.00 to 1.00) + 0.88 (95% CI: 0.66 to 1.00) x for WBC and y = - 0.22 (95% CI: - 0.80 to 0.20) + 0.40 (95% CI: 0.32 to 0.50) x for RBC. IQ200 Elite compared to Cobas u701 yielded the following equations: y = - 0.95 (95% CI: - 2.13 to 0.11) + 1.25 (95% CI: 1.08 to 1.44) x for WBC and y = - 1.20 (95% CI: - 1.80 to -0.30) + 0. 80 (95% CI: 0.55 to 1.00) x for RBC. Conclusions The two analyzers showed similar performances and good compatibility to manual microscopy. However, they are still inadequate in the determination of WBC, RBC, and EC in highly-pathological samples. Thus, confirmation by manual microscopic analysis may be useful.