Abdullah Taskin

Dimethoate-induced oxidative stress and DNA damage in Oncorhynchus mykiss.

The present study was conducted in order to investigate pro-oxidant activity of dimethoate in liver and brain tissues following sublethal pesticide exposure for 5, 15 and 30 d by using SOD, GPx, CAT enzyme activities and lipid peroxidation as biomarkers as well as DNA damaging potential via detecting% Tail DNA, Tail moment and Olive tail moment as endpoints in erythrocytes of Oncorhynchus mykiss in an in vitro experiment. Antioxidant enzyme activities were found to elicit two staged response which was an initial induction followed by a sharp inhibition in liver tissue while a sustained increase in GPx activity and slight stimulation in SOD activity were detected in brain tissue. Lipid peroxidation showed an ascending pattern throughout the exposure period in both tissues and a decreasing trend was determined in tissue protein levels which was proved to be positively correlated with duration. Similar findings were obtained from outcomes preferred to quantify DNA damage and TM was decided to reflect the extent of damage more sensitively because of determined positive correlation with concentrations applied. Considering these results, it can be concluded that oxidative stress condition evoked by dimethoate could not be responded effectively and genotoxic nature of pesticide was proven by determined clastogenic effect possibly via being an alkylation agent or stimulating the production of reactive species.

Protective Effects of Nigella Sativa on Intestinal Ischemia-Reperfusion Injury in Rats

ABSTRACT Background: In previous studies, it has been demonstrated that Nigella Sativa (NS) has protective effects against ischemia reperfusion injury on various organs. However, its protective effects on intestinal tissue against ischemia reperfusion injury are unclear. We aimed to determine whether NS prevents intestinal ischemia- reperfusion injury in rats. Materials and Methods: Thirty rats were divided into three groups as sham (group 1), control (group 2), and NS-treatment group (group 3). All rats underwent intestinal ischemia for 60 min followed by a 60-min period of reperfusion. Rats were intraperitoneally infused only 0.9%% saline solutions in group 2. Rats in the group 3 received NS (0,2 mL/kg) intraperitoneally, before ischemia and before reperfusion. Total antioxidant capacity (TAC), catalase (CAT), total oxidative status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) in ileum tissue were measured. Also, ileum tissue histopathology was evaluated by a light microscope. Results: The levels of liver enzymes in group 3 were significantly lower than those in group 2 (p <.01). TAC and CAT activity levels in ileum tissue were significantly higher in group 3 than in group 2. TOS, OSI, and MPO in ileum tissue were significantly lower in group 3 than group 2 (p <.05 for TOS and MPO; p < .01 for OSI). Histological tissue damage was milder in the NS treatment group than in the control group. Conclusion: Our results suggest that NS treatment protected the rats intestinal tissue against intestinal ischemia- reperfusion injury.

Evaluation of Oxidative Status in Patients with Brucellosis

Oxidative stress can be defined as an increase in oxidants and/or a decrease in antioxidant capacity. We aimed to determine total antioxidant capacity (TAC), total peroxide, malondialdehyde and catalase levels in plasma samples, and calculation of oxidative stress index (OSI) in patients with brucellosis to evaluate their oxidative status using a novel automated method. Sixty-nine patients with brucellosis and 69 healthy control subjects were included in the present study. Plasma levels of total peroxide and malondialdehyde were significantly increased in patients as compared with healthy controls (p<0.001 and p<0.001, respectively). In contrast, TAC level was significantly lower in patients as compared with controls (p<0.001). There was no statistically significant difference between the catalase results of the two groups (p>0.05). OSI level was significantly increased in patients as compared with healthy controls (p<0.001). In conclusion, oxidants were increased and antioxidants were decreased in patients with brucellosis. Oxidative stress was increased in patients with brucellosis.

Impact of contrast enhanced MRI on lymphocyte DNA damage and serum visfatin level

OBJECTIVES Nephrogenic systemic fibrosis is a novel clinical entity encountered in subjects undergoing contrast enhanced magnetic resonance imaging (MRI). The aim of the present study is to evaluate the impact of contrast enhanced MRI exposure on lymphocyte DNA damage and serum levels of visfatin. DESIGN AND METHODS Twenty-eight subjects undergoing contrast enhanced hypophysial MRI with omniscan were included in the study. Blood samples were drawn before MRI, after non-contrast MRI and after contrast enhanced MRI from each subject. Lymphocyte DNA damage was analyzed by the alkaline comet assay, whereas serum visfatin level was assessed with enzyme immuno assay. RESULTS Both lymphocyte DNA damage and serum visfatin levels were statistically significantly increased in samples withdrawn after contrast enhanced MRI compared to samples withdrawn after non-contrast enhanced MRI and baseline samples (ANOVA p<0.001, for both). CONCLUSIONS Findings of the present study revealed that the contrast enhanced MRI is associated with increased lymphocyte DNA damage and increased serum visfatin level.

Plasma nitrite levels, total antioxidant status, total oxidant status, and oxidative stress index in patients with tension-type headache and fibromyalgia

OBJECTIVES Tension-type headache (TTH) and fibromyalgia syndrome (FM) are worldwide seen chronic pain syndromes of unknown etiology. Despite the growing body of data on pathophysiology and generation mechanisms of pain; our knowledge on pain mechanisms in both FM and TTH is yet to be limited. PATIENTS AND METHODS We investigated the plasma nitrite levels, total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) in 35 TTH, 33 FM patients and 31 healthy controls. RESULTS The mean plasma nitrite levels and TAS levels were significantly low and OSI was found to be significantly high in TTH and FM groups compared to the control group (p=0.001, p=0.001, p=0.001 and p=0.001, respectively). The mean serum TOS levels were also significantly higher in FM group according to the control group (p=0.034), but there was not a significant difference between TTH and control groups (p=0.066). CONCLUSION These results indicated that; FM and TTH patients revealed higher oxidative stress index and lower total nitrite levels than healthy controls. We conclude that oxidative stress may have a role in the pathophysiological mechanisms of TTH and FM, although, whether it is the cause or the consequence, is not clear.

Relationship of oxidative stress in hepatitis B infection activity with HBV DNA and fibrosis.

Background The aim of this study was to evaluate oxidative stress in various clinical forms of hepatitis B infection and to investigate its role in the development of the chronic form of the disease. Methods Ninety-three patients with inactive hepatitis B surface antigen (HbsAg) carrier state (IHBCS), 65 patients with chronic hepatitis B infection (CHB), and 42 healthy adults were included in the study. The following values were measured and compared in patient groups: total antioxidant status (TAS), total oxidative stress (TOS), oxidative stress index (OSI), sulfhydryl (SH), lipid peroxidation (LOOH), catalase (CAT), and ceruloplasmin. In patients with chronic hepatitis B, these values were compared with HBV DNA and fibrosis levels. Results ALT, TOS, LOOH, and OSI levels were higher in the CHB group compared to the other groups (P<0.001). Catalase levels increased in the CHB and IHBCS groups compared to the control group (P<0.001). Total aminooxidant and ceruloplasmin levels were found to be lowest in the CHB group and highest in the control group (P<0.001). Sulfhyrdyl was higher in the control group compared to the other groups (P<0.001). In the CHB group, there was no correlation between the HBV DNA and OSI (P>0.05). Conclusions These finding suggested that oxidative stress is associated with hepatitis B activity.

Elevated serum S-100B levels in children with temporal lobe epilepsy

PURPOSE An elevated level of S-100B in serum is generally considered to be a biochemical marker of nervous tissue damage. According to our knowledge, no studies have evaluated the serum S-100B protein concentration in children with temporal lobe epilepsy. The objective of this study was to measure the serum levels of S-100B protein in pediatric cases with temporal epilepsy. METHODS This case-controlled cross-sectional study was performed at the Department of Pediatric Neurology, Harran University School of Medicine, Sanliurfa, in Turkey. Serum S-100B protein levels were studied in 19 (12 females, 7 males) children with temporal lobe epilepsy and in 25 (15 females, 10 males) healthy control subjects. Serum samples were collected within 30min after a complex partial seizure, and serum S-100B protein levels were measured with an electrochemiluminescence immunoassay for the quantification of protein (ECLIA kit, Roche(®) Diagnostics, Germany). RESULTS The mean serum concentration of S-100B protein was 0.12±0.02μg/L in the temporal lobe epilepsy group and 0.07±0.01μg/L in the control group. The patients showed significantly elevated S-100B protein levels compared with healthy controls (P<0.001). CONCLUSION Our data suggest that increased S-100B protein levels in the serum might reflect neuronal damage in the brains of children with temporal lobe epilepsy. These results do confirm the previous findings of elevated S-100B protein levels in adult patients with temporal lobe epilepsy.

Oxidative Stress Increased in Healthcare Workers Working 24-Hour On-Call Shifts

Introduction:Long work hours, night shifts, stressful situations and insufficient social support increase levels of anxiety and depression and decrease motivation to perform among healthcare professionals. In this study, we evaluated oxidative stress levels in medical residents working 24-hour on-call shifts, and in nurses, relative to non-healthcare hospital staff in sedentary positions. We also measured serum prolidase activity, a measure of collagen turnover, as an objective proxy for level of physical activity. Methods:Fifty-five male and 15 female medical residents on 24-hour, in-house, on-call duty, and 45 nurses and 30 (15 male/15 female) non-healthcare staff working 8-hour shifts were recruited. All were healthy nonsmokers. Parameters of oxidative stress and serum prolidase activity were measured twice for each subject, upon arising at 8 am after an overnight fast; and then again near the end of the work shift, or after 16 hours of consecutive work (at 12 pm) for residents. Results:After hours of continuous work, serum total oxidative status and the oxidative stress index increased significantly, whereas total antioxidant status decreased (all P < 0.0001) in healthcare staff (nurses, male and female residents). All these variables remained virtually unchanged in non-healthcare staff. Similarly, serum prolidase activity increased in healthcare staff (P < 0.0001), but failed to increase statistically in non-healthcare staff. Conclusions:Healthcare workers suffer increased oxidative stress after prolonged work hours, especially while still on duty. Possible mechanisms for this include increased workload and, perhaps, psychological stress as well. However, long-term studies are needed to clarify the effects of sustained exposure to oxidative stress.

Oxidative stress in chronic otitis media

Chronic otitis media usually presents with a benign tumor-like lesion of the temporal bone known as a cholesteatoma. The role of oxidative stress in the pathogenesis of chronic otitis media and cholesteatoma has not yet been fully explored. Therefore, the aim of this study was to investigate the oxidative stress markers and antioxidant enzymes in patients with cholesteatomatous and noncholesteatomatous chronic otitis media and in healthy subjects. A prospective controlled trial was performed on cholesteatomatous and noncholesteatomatous chronic otitis media patients in a tertiary referral center in a university hospital. A total of 75 subjects, including 25 cholesteatomatous and 25 noncholesteatomatous chronic otitis media patients and 25 healthy subjects participated in this study. Serum total oxidant status (TOS) and oxidative stress index (OSI) levels were significantly increased in the patient groups with or without cholesteatoma compared with the control group. Serum total antioxidant status (TAS) levels and Paraoxonase and arylesterase activity were significantly lower in the patient groups with or without cholesteatoma compared with the control group. Serum TOS and OSI levels were lower in the noncholesteatomatous group, whereas serum TAS levels were higher compared with the cholesteatomatous group. Serum arylesterase activity was significantly lower in the noncholesteatomatous group compared with the control group. The results of this study reveal that in cholesteatoma cases, the oxidative stress and antioxidant enzyme imbalance were more significant than in cases of chronic otitis media without cholesteatoma.

The effect of maternal number of births on oxidative and antioxidative systems in cord blood

Objective: The aim of this study is to evaluate the relationship between cord blood oxidative and antioxidative status and maternal parity number. Methods: Patients are grouped according to the maternal parity number: primiparous group (n = 36), multiparous group (n = 40), and grand multiparous group (n = 26). Cord blood samples are obtained in all subjects and assessed for total antioxidant capacity (TAC), total oxidant status (TOS) and oxidative stress index (OSI). The serum TAC and TOS were evaluated by using an automated colorimetric measurement method. Results: TAC levels are significantly higher and oxidative stress indicators are significantly lower in newborns of primiparous women compared to multiparous women p < 0.05 for all). TAC level is increased, whereas TOS and OSI levels are decreased in newborns of grand multiparous mothers compared to primiparous mothers. TAC level is significantly higher, whereas TOS and OSI levels are significantly lower in newborns of grand multiparous women compared to multiparous women (p < 0.05 for all). Conclusions: These results suggest a relation between higher maternal parity and increased oxidative stress and decreased antioxidant defense capacity. On the other hand, the compensatory mechanisms improve the antioxidant defense system in newborns of grand multiparous women and may prevent oxidative stress.