Browsing by Author "Djuric, D. (36016317400)"

Despite worldwide popularity of soccer, there are still insufficient data about the effects of training process on oxidative stress-induced damage, which may occur during chronic exercise. The present study aimed to determine the effects of a six-month training programme on basal redox status of young male soccer players. The study included 26 male soccer players, aged 12-13, who participated in a six-month training programme, and 26 agematched non-athletes who were not implemented in the training process. Blood samples were collected (before and after six-month training programme) in order to measure the following oxidative stress markers: index of lipid peroxidation (measured as TBARS), nitrites (NO2-), superoxide anion radical (O 2-), hydrogen peroxide (H2O2), superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH) level. After six months, the levels of TBARS and NO2- were significantly increased, while the O2- and H 2O2 remained unchanged. On the other hand, SOD and CAT activity increased, while GSH decreased. A carefully prepared training programme could strengthen most components of antioxidant defence systems and, except lipid peroxidation, does not promote oxidative stress in response to regular physical activity. These findings could help in the improvement of training programmes for young athletes. © 2013 Akadémiai Kiadó, Budapest.

Background and aim: Reduced baroreflex sensitivity (BRS), decreased heart rate variability (HRV) and increased blood pressure (BP) variability have serious consequences for target organ damage in patients with hypertension, beside the BP level. The study was aimed to evaluate acute and long-term effects of enalapril, on BRS and HRV in individuals with prehypertension and mild essential hypertension. Methodology: We enrolled in the study 85 patients (male 53%, age 42-67) with prehypertension and mild hypertension (systolic blood pressure ≥120 mmHg or diastolic blood pressure ≥80 mmHg). All patients were tested before, 30 minutes after first oral enalapril dose and three weeks after monotherapy with enalapril. The methodology included: beat to beat HRV analysis, BRS measurements with sequence technique, ECG with short term and 24-hour HRV analysis, 24-hour ambulatory blood pressure monitoring with systolic and diastolic BP variability analysis. Patients were divided into groups with sympathetic or vagal predominance based on Autonomic Nervous System Adjustment (ANSA) method. Results: 1) 30 min after initial dose enalapril significantly and effectively reduced systolic BP with shift towards the parasympathetic predominance as reflected in decreased heart rate and low frequency (LF) to high frequency (HF) ratio (LF/HF ratio); 2) chronic enalapril therapy effectively reduced BP, including both systolic BP, diastolic BP and pulls pressure, had positively influence on dipping status, but did not significantly change BP variability; 3) in the whole patient group chronic enalapril therapy did not significantly change HRV, but it significantly decreased LF(nu) in the patient with high basal sympathetic activity, and significantly increased LF(nu) in patients with high basal vagal activity; enalapril also significantly decreased HF (nu) in patients with high basal parasympathetic activity; 4) despite initial, transit changes in maximal and minimal slope of BRS enalapril did not significantly affect sensitivity of spontaneous baroreflex activation. Conclusion: Initial enalapril dose significantly reduced systolic BP and had beneficial effects on autonomic tone and baroreflex sensitivity. Chronic enalapril therapy effectively reduced BP without significant influence on BRS, but had significant autonomic effects on HRV when initial autonomic profile in each patient was analyzed by ANSA. Analyzed by ANSA method chronic enalapril therapy managed to retrieve disturbed sympathovagal balance and established autonomic equilibrium. © 2011 Akadémiai Kiadó, Budapest.

In patients with unreconstructable arterial occlusive disease distal venous arterialization (DVA) seems to be a promising option in the treatment. The goals of this prospective study were to assess clinical efficiency and possible impact of DVA on tissue damage by estimating oxidative status of patients with critical limb ischemia treated with this procedure. The subjects were 60 randomized patients: 30 were undergoing DVA and 30 were treated with antiaggregation therapy. During the mean follow-up period (6.13 ± 4.32 months for DVA vs. 6.74 ± 0.5 months for antiaggregation therapy) survival (p < 0.01), limb salvage (p < 0.001), pain relief (p < 0.001) and wound healing (p < 0.001) rates were significantly different between the two groups of patients in favor of the DVA group. Ten minutes after declamping we observed a decreasing trend in the lactate level in the blood of the deep venous system (p < 0.001). Also, on postoperative day 7 digital systolic pressure and digital-brachial index were higher than before the operation (p < 0.001). In blood samples collected immediately before and successively at 1, 3, 5 and 10 min postoperatively, prooxidative status (thiobarbituric acid reactive substances, O2-, H2O2 and nitric oxide) and antioxidative enzymes (superoxide dismutase, catalase and glutathione reductase) were determined spectrophotometrically. Using the nonparametric Friedman test, we noted statistically nonsignificant differences (p > 0.05) in values of both prooxidative parameters and enzymes of the antioxidative defense system, before and successively at 1, 3, 5 and 10 min after operation. These results indicate that there was no statistically significant reperfusion injury after revascularization, which could have been expected after this surgical procedure, thus confirming its validity in these patients. Copyright © 2012 S. Karger AG, Basel.

Background: The Aim of our study was to present and analyze the distribution of cerebrovascular insult types and their localization in patients with normal body temperature by means of computerized tomography, and in those with elevated body temperature by means of neuroradiographic findings. Methods: In our study we evaluated 103 patients that suffered a cerebrovascular insult and were treated at Special Hospital for Cerebrovascular disorders "Saint Sava" in Belgrade. All patients were divided into two groups due to the presence of elevated body temperature. Results: Fever as a complication in period after acute cerebrovascular insult is presented in almost every fifth patient. In the group of patients with fever, the most common presentation was acute ischemic cerebrovascular insult, namely in 45.63 %, while in the group of patients with normal body temperature, the most common presentation was lacunar infarction, namely in 46.60 % of participants. The most frequent localization of cerebrovascular insult is in cortex and subcortex regions. Conclusions: It should be stated that some patients with specific types of cerebrovascular insult as well as their localization are at higher risk for development of complications. This study suggests that appropriate diagnostics as well as prevention and management of in-hospital complications could improve the short-term and long-term prognoses after stroke (Tab. 3, Ref. 14). Full Text (Free, PDF) www.bmj.sk.

The aim of the study was to examine the effects of chronic exercise training on seizures induced by homocysteine thiolactone (HCT) in adult rats. Rats were assigned to: sedentary control; exercise control; sedentary+HCT; exercise+HCT group. Animals in the exercise groups ran 30 min daily on a treadmill for 30 consecutive days (belt speed 20 m/min), while sedentary rats spent the same time on the treadmill (speed 0 m/min). On the 31st day, the HCT groups received HCT (8.0 mmol/kg), while the control groups received vehicle. Afterwards, convulsive behavior and EEG activity were registered. Lipid peroxidation, superoxide dismutase (SOD) and catalase (CAT) activity were ascertained in the rat hippocampus. No signs of seizures were registered in sedentary and exercise control rats. Seizure latency was increased, while number of seizure episodes and spike-and-wave discharges (SWD) in EEG were decreased in the exercise+HCT compared to the sedentary+HCT group. Seizure incidence, the severity thereof and duration of SWDs were not significantly different between these groups. Exercise partly prevented increase of lipid peroxidation and decrease of the SOD and CAT activity after HCT administration. These results indicate beneficial effects of exercise in model of HCT-induced seizures in rats, what could be, at least in part, a consequence of improved antioxidant enzymes activity. © Georg Thieme Verlag KG Stuttgart New York.

The aim of the study was to examine the effects of chronic exercise training on seizures induced by homocysteine thiolactone (HCT) in adult rats. Rats were assigned to: sedentary control; exercise control; sedentary+HCT; exercise+HCT group. Animals in the exercise groups ran 30 min daily on a treadmill for 30 consecutive days (belt speed 20 m/min), while sedentary rats spent the same time on the treadmill (speed 0 m/min). On the 31st day, the HCT groups received HCT (8.0 mmol/kg), while the control groups received vehicle. Afterwards, convulsive behavior and EEG activity were registered. Lipid peroxidation, superoxide dismutase (SOD) and catalase (CAT) activity were ascertained in the rat hippocampus. No signs of seizures were registered in sedentary and exercise control rats. Seizure latency was increased, while number of seizure episodes and spike-and-wave discharges (SWD) in EEG were decreased in the exercise+HCT compared to the sedentary+HCT group. Seizure incidence, the severity thereof and duration of SWDs were not significantly different between these groups. Exercise partly prevented increase of lipid peroxidation and decrease of the SOD and CAT activity after HCT administration. These results indicate beneficial effects of exercise in model of HCT-induced seizures in rats, what could be, at least in part, a consequence of improved antioxidant enzymes activity. © Georg Thieme Verlag KG Stuttgart New York.

Within the past four decades, the efforts of investigators worldwide have established the amino acid homocysteine (Hcy) as an important factor in arteriosclerosis and ageing. The amino acid homocysteine is a unique candidate for the study of different age-related pathological conditions, namely vascular diseases, dementia disorders and late-life depression, due to its multiple roles in different pathways leading to atherosclerosis and neurotoxicity. Especially, the role of homocysteine in predicting risk for atherothrombotic vascular disease has been evaluated in several observational studies in a large number of patients. These studies show that the overall risk for vascular disease is small, with prospective, longitudinal studies reporting a weaker association between homocysteine and atherothrombotic vascular disease compared to retrospective case-control and cross-sectional studies. Furthermore, randomised controlled trials of homocysteine-lowering therapy have failed to prove a causal relationship. On the basis of these results, there is currently insufficient evidence to recommend routine screening and treatment of elevated homocysteine concentrations with folic acid and other vitamins to prevent atherothrombotic vascular disease.

The aim of this study was to investigate the iron concentrations in serum and carotid plaque in patients with different morphology of carotid atherosclerotic plaque and compared with other metal ions. Carotid endarterectomy due to the significant atherosclerotic stenosis was performed in 91 patients. Control group consisted of 27 patients, without carotid atherosclerosis. Atherosclerotic plaques were divided into four morphological groups, according to ultrasonic and intraoperative characteristics. Iron, copper and zinc concentration in plaque, carotid artery and serum were measured by spectrophotometry. Serum iron concentrations were higher in patients with hemorrhagic plaques in comparison to the control group (4.7 μmol/l ± 1.2 vs. 2.1 μmol/l ± 0.8, p < 0.05). Iron concentrations were higher in patients with hemorrhagic plaques in comparison to fibrolipid plaques (72.1 ± 14.3 μg/g vs. 39.3 ± 22.9 μg/g; p < 0.05). Negative significant correlation was found for zinc in serum and plaque iron concentration in patients (p < 0.05). We also demonstrated positive significant correlation for copper and iron in serum (p < 0.05). The data obtained in the current study are consistent with the hypothesis that high iron levels may contribute to atherosclerosis and its complications as factors in a multifactorial disease. © 2015 Akadémiai Kiadó, Budapest.

The aim of the present study was to examine the effect of subchronic co-administration of folic acid (F) and L-arginine (A) on behavioural and electroencephalographic (EEG) characteristics of DL homocysteine thiolactone (H) induced seizures in adult rats. The activity of membrane ATPases in different brain regions were also investigated. Rats were treated with F, A, or vehicle for 15 days (regimen: F 5 mg/kg + A 500 mg/kg (F5A500); F 10 mg/kg + A 300 mg/kg (F10A300)). Seizures were elicited by convulsive dose of H (H, F5A500H, F10A300H) Subchronic supplementation with F and A did not affect seizure incidence, number of seizure episodes, and severity in F5A500H and F10A300H groups vs. H group. However, a tendency to increase latency and decrease the number of seizure episodes was noticed in the F10A300H group. EEG mean spectral power densities during ictal periods were significantly lower in F10A300H vs. H group. The activity of Na+/K+-ATPase and Mg2+-ATPase was significantly increased in almost all examined structures in rats treated with F and A. We can conclude that subchronic supplementation with folic acid and L-arginine has an antiepileptic effect in DL homocysteine thiolactone induced epilepsy. © 2016, Canadian Science Publishing. All rights reserved.

The aim of the present study was to examine the effect of subchronic co-administration of folic acid (F) and L-arginine (A) on behavioural and electroencephalographic (EEG) characteristics of DL homocysteine thiolactone (H) induced seizures in adult rats. The activity of membrane ATPases in different brain regions were also investigated. Rats were treated with F, A, or vehicle for 15 days (regimen: F 5 mg/kg + A 500 mg/kg (F5A500); F 10 mg/kg + A 300 mg/kg (F10A300)). Seizures were elicited by convulsive dose of H (H, F5A500H, F10A300H) Subchronic supplementation with F and A did not affect seizure incidence, number of seizure episodes, and severity in F5A500H and F10A300H groups vs. H group. However, a tendency to increase latency and decrease the number of seizure episodes was noticed in the F10A300H group. EEG mean spectral power densities during ictal periods were significantly lower in F10A300H vs. H group. The activity of Na+/K+-ATPase and Mg2+-ATPase was significantly increased in almost all examined structures in rats treated with F and A. We can conclude that subchronic supplementation with folic acid and L-arginine has an antiepileptic effect in DL homocysteine thiolactone induced epilepsy. © 2016, Canadian Science Publishing. All rights reserved.

Influence of folic acid on the CNS is still unclear. Folate has a neuroprotective effect, while on the other hand excess folate can exacerbate seizures in epileptics. The aim of the present study was to examine the effect of subchronic administration of folic acid on behavioural and electroencephalographic (EEG) characteristics of DL homocysteine thiolactone induced seizures in adult rats. The activity of Na+/K+-ATPase and Mg 2+ -ATPase in different brain regions was investigated. Adult male Wistar rats were divided into groups: 1. Controls (C, 0.9% NaCl); 2. DL homocysteine-thiolactone 8.0 mmol/kg (H); 3. Subchronic supplementation with folic acid 5 mg/kg for 7 days (F) and 4. Subchronic supplementation with F + single dose of H (FH). Seizure behaviour was assessed by incidence, latency, number and intensity of seizure episodes. Seizure severity was described by a descriptive scale with grades 0-4. For EEG recordings, three gold-plated recording electrodes were implanted into the skull. Subchronic supplementation with folic acid did not affect seizure incidence, median number of seizure episodes and severity in FH, comparison with H (p > 0.05). The majority of seizure episodes in all groups were of grade 2. There were no significant differences in lethal outcomes at 24 h upon H injection in the FH vs. H group. The activity of Na+/K+- ATPase and Mg 2+- ATPase was significantly increased in almost all examined structures in the FH vs. H group. Subchronic folic acid administration did not exacerbate H induced seizures and completely recovered the activity of ATPases. © 2015 Akadémiai Kiadó, Budapest.

It is known that adrenaline ( L - epinephraie) produces positive inotropic effect on isolated right ventricle of rat heart. Purpose : The aim of our study was to investigate inotropic effect of adrenaline on the isolated right ventricle of Wistar rat heart in the presence and absence of endocardial endothelium. Methods : Endocardial endothelium was damaged by immersion for I s of right ventricle with Triton X-100 dissolved in a Crebs-Ringer solution at 20°C followed by rapid abundant wash in Tyrode's solution at 35°C. Each ventricle was put on a boot electrode and than placed in a bath with Tyrode's solution bubbled with 95% O 2 /5% CO 2 The volume of the bath was 25 ml, pH=7.4 and it's temperature was kept on 37°C. Contractions were induced with square wave impulses of twice the diastolic threshold and a duration of 5 ms at a frequency on I Hz. The contractions were recorded via an isometric transducer (sensitivity of 0.05 g/cm) into a microdynarnometer (7050 Ugo Basile). After stabilization period of 30 min adrenaline (Sigma, USA), in a dose 10 5 mol/l, which produced maximal positive inotropic effect, was added into the bath and contractions were recorded continuously for another 60 min. Results : The positive inotropic effect of adrenaline in both groups was expressed immediately after the application. In the group with intact endocardial endothelium the maximal inotropic effect was reached in 2 nd min. (92% higher than in the controls, p<0.05). In the group with damaged endocardial endothelium it was reached in 3 rd min. (183% higher than the controls, p<0.05). The inotropic effect of adrenaline was approximately 100% higher in the experimental group without endocardial endothelium.

This study aimed to assess the role of H2S in homocysteine-induced cardiodynamic effects in the isolated rat heart. The hearts were retrogradely perfused according to the Langendorff technique. The maximum and minimum rates of pressure in the left ventricle (dp/dt max, dp/dt min), systolic and diastolic left ventricular pressures (SLVP, DLVP), heart rate (HR), and coronary flow (CF) were measured. A spectrophotometrical method was used to measure the following oxidative stress markers: index of lipid peroxidation (thiobarbituric acid reactive substances, TBARS), nitrite level (NO2-), superoxide anion radicals (O2•-), and hydrogen peroxide (H2O2) concentrations. The administration of 10 μmol/l DL-homocysteine (DL-Hcy) alone decreased dp/dt max, SLVP, and CF but did not change any oxidative stress parameters. The administration of 10 μmol/l DL-propargylglycine (DL-PAG) decreased all cardiodynamic parameters and increased the concentration of O2•-. The co-administration of DL-Hcy and DL-PAG induced a significant decrease in all estimated cardiodynamic parameters and decreased the concentration of NO2- and O2 •- but increased the levels of TBARS and H2O2. Homocysteine shows a lower pro-oxidative effect in the presence of hydrogen sulfide (H2S), which indicates a potential anti-oxidative capacity of H2S. © 2016 Akadémiai Kiadó, Budapest.