Vladimir Zivkovic

University of Kragujevac, Krabujevac, Central Serbia, Serbia

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Publications (32)25.59 Total impact

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    ABSTRACT: We estimated the influence of acute glucagon applications on 3H-histamine uptake by the isolated guinea-pig heart, during a single 3H-histamine passage through the coronary circulation, before and during anaphylaxis, and the influence of glucagon on level of histamine, NO, , and H2O2 in the venous effluent during anaphylaxis. Before anaphylaxis, glucagon pretreatment does not change 3H-histamine Umax and the level of endogenous histamine. At the same time, in the presence of glucagon, 3H-histamine Unet is increased and backflux is decreased when compared to the corresponding values in the absence of glucagon. During anaphylaxis, in the presence of glucagon, the values of 3H-histamine Umax and Unet are significantly higher and backflux is significantly lower in the presence of glucagon when compared to the corresponding values in the absence of glucagon. The level of endogenous histamine during anaphylaxis in the presence of glucagon (6.9–7.38 × 10−8 μM) is significantly lower than the histamine level in the absence of glucagon (10.35–10.45 × 10−8 μM). Glucagon pretreatment leads to a significant increase in NO release (5.69 nmol/mL) in comparison with the period before glucagon administration (2.49 nmol/mL). Then, in the presence of glucagon, level fails to increase during anaphylaxis. Also, our results show no significant differences in H2O2 levels before, during, and after anaphylaxis in the presence of glucagon, but these values are significantly lower than the corresponding values in the absence of glucagon. In conclusion, our results show that glucagon increases NO release and prevents the increased release of free radicals during anaphylaxis, and decreases histamine level in the venous effluent during cardiac anaphylaxis, which may be a consequence of decreased histamine release and/or intensified histamine capturing by the heart during anaphylaxis.
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    ABSTRACT: The aim of this study was to assess the oxidative stress status in rheumatoid arthritis (RA) by measuring markers of free radical production, systemic activity of disease, and levels of antioxidant. 52 RA patients and 30 healthy controls were included in the study, and clinical examination and investigations were performed and disease activity was assessed. Peripheral blood samples were used for all the assays. We assessed the markers of oxidative stress, including plasma levels of index of lipid peroxidation-thiobarbituric acid reactive substances (TBARS), hydrogen peroxide (H2O2), superoxide anion radical (O2 (-)), nitric oxide (NO), and superoxide dismutase activity (SOD), catalase activity (CAT) and glutathione levels in erythrocytes. In the RA group, levels of H2O2, O2 (-), and TBARS were significantly higher than in controls (4.08 ± 0.31 vs. 2.39 ± 0.13 nmol/l, p < 0.01; 8.90 ± 1.28 vs. 3.04 ± 0.38 nmol/l, p < 0.01, 3.65 ± 0.55 vs. 1.06 ± 0.17 μmol/l, p < 0.01). RA patients had significantly increased SOD activity compared with healthy controls (2,918.24 ± 477.14 vs. 643.46 ± 200.63UgHbx103, p < 0.001). Patients had significantly higher levels of pro-oxidants (O2 (-), H2O2, and TBARS) compared to controls, despite significantly higher levels of SOD. Significant differences were also observed in serum levels of NO in patients with high-diseases activity. Our findings support an association between oxidative/nitrosative stress and RA. Stronger response in samples with higher diseases activity suggests that oxidative/nitrosative stress markers may be useful in evaluating the progression of RA as well as in elucidating the mechanisms of disease pathogenesis.
    Molecular and Cellular Biochemistry 03/2014; · 2.33 Impact Factor
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    ABSTRACT: Eicosanoids lead to the promotion of inflammation, cause fever and pain and have many other effects. NSAIDs block the action of cyclooxygenase (COX) during the process of converting arachidonic acid into inflammatory mediators, thus reducing the symptoms of inflammation. Investigations focusing on nonselective COX inhibitors, used in high doses, revealed harmful effects on myocardial function. The aim of our study was to assess the effects of two nonselective NSAIDs, diclofenac and ibuprofen, on cardiodynamic parameters, coronary flow and oxidative stress biomarkers in isolated rat hearts. The hearts of male Wistar albino rats were excised and retrogradely perfused according to the Langendorff technique at gradually increased coronary perfusion pressures (40–120 cm H2O). The experiments were performed under controlled conditions (Krebs–Henseleit physiological solution). The hearts were perfused with 10 μmol/l diclofenac and 10 μmol/l ibuprofen. The heart function parameters, including the maximum rate of pressure development (dp/dt max), minimum rate of pressure development (dp/dt min), systolic left ventricular pressure (SLVP), diastolic left ventricular pressure (DLVP), mean perfusion pressure (MBP) and heart rate (HR), were continuously registered. Coronary flow (CF) was measured flowmetrically. Oxidative stress markers, including the index of lipid peroxidation measured as TBARS, nitric oxide measured through nitrites (NO2-), superoxide anion radical (O), and hydrogen peroxide (H2O2) in the coronary venous effluent, were assessed spectrophotometrically. Our results showed that diclofenac affected cardiodynamic parameters more significantly than did ibuprofen. Furthermore, the present data indicate that both estimated COX inhibitors do not promote the production of reactive oxygen species.
    Serbian Journal of Experimental and Clinical Research 01/2014; 15(1):11-19.
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    ABSTRACT: Vibroacoustics, a scientific field that has been intensively studied for the last thirty years, uses the properties of sound waves (infrasound, ultrasound, noise and music) to induce vibrations that, like a sound wave, may have both useful and harmful effects. The aim of this study was to examine the effects of vibroacoustically induced microvibrations on arterial blood pressure and markers of oxidative stress in the blood. The experiments were performed on Wistar male rats that had a 180-200 g body mass and were divided into control and experimental groups (6 rats in each). In the experimental group, microvibrations were induced using the Vitafon vibroacoustic apparatus (Vitafon, St. Petersburg, Russian Federation), which delivers sound waves of varying frequencies by a process called “phoning”. Up to 60 minutes of phoning time was delivered to the kidney and liver using 4 different regimens that included a 5-minute stabilization time; up to four 10-minute phoning regimens, with 5-minute breaks between each single regimen, at a 30 Hz-18000 kHz frequency range;, and 2.8 μm-12.3 μm microwave amplitudes. After the completion of a phoning regimen, animals were sacrificed and the oxidative stress markers were measured in blood samples (O2-, H2O2, nitrites, lipid peroxidation index, superoxide dismutase, catalase, and glutathione) and compared with the values of markers in the control group. Systolic arterial pressure was analyzed after the acute application of up to four different regimens of vibroacoustic microvibrations. Systolic arterial pressure decreased significantly during the administration of the second regimen in comparison to the control group. Systolic arterial pressure returned, almost completely, to the initial value after the administration of the third and fourth regimens. There was no significant change in diastolic arterial pressure after the acute administration of up to four different regimens, although the pressure decreased slightly after the first and second regimens and returned to the initial value during the administration of the third and fourth regimens. Analysis of oxidative stress markers showed a statistically significant change in the catalase level. No statistically significant differences were found in the other oxidative stress markers analyzed. Further research is needed to clarify the physiological effects of low compared to high frequencies of vibroacoustically induced microvibrations and their possible therapeutic significance.
    Serbian Journal of Experimental and Clinical Research 01/2014; 15(2):83-88.
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    ABSTRACT: Despite the widespread clinical use of cyclooxygenase (COX) inhibitors, dilemmas still exist about potential impact of these drugs on cardiovascular system. The present study was aimed to estimate the effects of different COX inhibitors (meloxicam, acetylsalicylic acid [ASA], and SC-560) on oxidative stress in isolated rat heart, with special focus on L-arginine/NO system. The hearts of male Wistar albino rats (total number n = 96, each group 12 rats, 8 weeks old, body mass 180-200 g) were retrogradely perfused according to the Langendorff technique at gradually increased perfusion pressure (40-120 cmH2O). After control experiments the hearts were perfused with the following drugs: 100 μmol/l ASA (Aspirin), alone or in combination with 30 μmol/l L-NAME, 0.3 μmol/l meloxicam (movalis) with or without 30 μmol/l L-NAME, 3 μmol/l meloxicam (alone or in combination with 30 μmol/l L-NAME), 30 μmol/l L-NAME, and administration of 0.25 μmol/l SC-560. In samples of coronary venous effluent the following oxidative stress markers were measured spectrophotometrically: index of lipid peroxidation (measured as thiobarbituric acid reactive substances [TBARS]), superoxide anion radical release (O2 (-)), and hydrogen peroxide (H2O2). While ASA was found to have an adverse influence on redox balance in coronary circulation, and coronary perfusion, meloxicam and SC-560 do not negatively affect the intact model of the heart. Furthermore, all effects were modulated by NOS inhibition. It seems that interaction between COX and L-arginine/NO system truly exists in coronary circulation, and can be one of the possible causes for achieved effects. That means: those effects induced by different inhibitors of COX are modulated by subsequent inhibition of NOS.
    Molecular and Cellular Biochemistry 06/2013; · 2.33 Impact Factor
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    ABSTRACT: 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 age-matched 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 (O2-), 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 H2O2 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.
    Acta Physiologica Hungarica 03/2013; 100(1):64-76. · 0.88 Impact Factor
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    ABSTRACT: Considering the adverse effects of DL-homocysteine thiolactone hydrochloride (DL-Hcy TLHC) on vascular function and the possible role of oxidative stress in these mechanisms, the aim of this study was to assess the influence of DL-Hcy TLHC alone and in combination with specific inhibitors of important gasotransmitters, such as L-NAME, DL-PAG, and PPR IX, on cardiac contractility, coronary flow, and oxidative stress markers in an isolated rat heart. The hearts were retrogradely perfused according to the Langendorff technique at a 70 cm H2O and administered 10 μ M DL-Hcy TLHC alone or in combination with 30 μ M L-NAME, 10 μ M DL-PAG, or 10 μ M PPR IX. The following parameters were measured: dp/dt max, dp/dt min, SLVP, DLVP, MBP, HR, and CF. Oxidative stress markers were measured spectrophotometrically in coronary effluent through TBARS, NO2, O2 (-), and H2O2 concentrations. The administration of DL-Hcy TLHC alone decreased dp/dt max, SLVP, and CF but did not change any oxidative stress parameters. DL-Hcy TLHC with L-NAME decreased CF, O2 (-), H2O2, and TBARS. The administration of DL-Hcy TLHC with DL-PAG significantly increased dp/dt max but decreased DLVP, CF, and TBARS. Administration of DL-Hcy TLHC with PPR IX caused a decrease in dp/dt max, SLVP, HR, CF, and TBARS.
    BioMed research international. 01/2013; 2013:318471.
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    ABSTRACT: Despite the worldwide popularity of football, there is still insufficient data on the effects of the training process on the immune system, followed via serum values of cytokines measured during or following constant exercise. This study aims to assess the effects of a six-month programmed physical activity, on activity of inflammatory mediators in young footballers. The study included 26 players, male, aged 12-13 years, who participated in the six-month training program and 26 sedentary boys who are not entering of the previously mentioned program. Blood samples, which measured levels of the inflammatory mediators TNF-α (tumor necrosis factor alpha) and IL-6 (interleukin six) were taken before and after a six-month training programs. Significantly low values of IL-6 serum (34,73±33,23; 12,52±3,35; p=0,000**) were measured, while the concentration of TNF in the serum did not significantly alter after a 6-month training process. The results obtained in this way can be of an invaluable value in the organizing and dosing of physical activities in young football players.
    Journal of Advances in Biology. 01/2013; 3(3):257-264.
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    ABSTRACT: Although the relationship between exercise and oxidative stress has been intensively investigated for over 3 decades, there remains a lack of empirical data on exercise-induced oxidative stress in athletes engaged in sporting games, specifically among the population of elite female athletes. Blood samples were taken from female handball players of the Serbian U20 national team at the beginning and at the end of a one-month preparatory training period, as well as immediately before and after acute treadmill exercise. Levels of superoxide anion radical, hydrogen peroxide, nitric oxide and lipid peroxidation were measured in plasma samples while levels of reduced glutathione and the activity of superoxide dismutase and catalase were measured in erythrocytes. Both experimental protocols demonstrated significant increases in plasma levels of hydrogen peroxide and decreases in superoxide dismutase activity in erythrocytes. Despite the increase in plasma levels of hydrogen peroxide after both the treadmill exercise and the one-month training period, the levels of the two antioxidants responsible for eliminating H2O hydrogen peroxide were not significantly different, as may be expected. Moreover, the marker of lipid peroxidation, TBARS, was not significantly increased. These findings suggest that the first line of antioxidative defence was effective in the prevention of oxidative stress among young female handball players.
    Serbian Journal of Experimental and Clinical Research 01/2013; 14(4):161-168.
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    ABSTRACT: Despite the widespread clinical use of cyclooxygenase (COX) inhibitors, dilemmas regarding the potential impact of these drugs on the cardiovascular system persist. To estimate the effects of different COX inhibitors (meloxicam, acetylsalicylic acid [ASA] and SC-560) on cardiac function and coronary flow in isolated rat hearts, with special focus on the L-arginine/nitric oxide system. The hearts of eight-week-old male Wistar albino rats (n=72; 12 rats per group; body mass 180 g to 200 g) were retrogradely perfused according to the Langendorff technique at gradually increased perfusion pressure (40 cmH2O to 120 cmH2O). After control experiments, the hearts were perfused with the following drugs: 100 μM ASA, alone or in combination with 30 μM N(ω)-nitro-L-arginine monomethyl ester (L-NAME), 0.3 μM meloxicam with or without 30 μM L-NAME, 3 μM meloxicam with or without 30 μM L-NAME, 30 μM L-NAME and 0.25 μM SC-560. In the control and experimental groups, the following parameters of heart function were continuously recorded: maximum rate of left ventricular pressure development, minimum rate of left ventricular pressure development, systolic left ventricular pressure, diastolic left ventricular pressure, heart rate and mean blood pressure. Coronary flow was measured flowmetrically. The amount of released NO2 (-) was determined spectrophotometrically in coronary venous effluent. While meloxicam and SC-560 were found to have an adverse influence on cardiac function and coronary perfusion, ASA did not negatively affect the intact model of the heart. It appeared that interaction between COX and the L-arginine/nitric oxide system truly exists in coronary circulation and may explain the causes of the observed effects.
    Experimental and clinical cardiology 01/2013; 18(2):e102-10. · 1.10 Impact Factor
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    ABSTRACT: Cardiovascular (CV) morbidity and mortality are increased in patients with rheumatoid arthritis (RA). Our study aim was to determine the relationship between carotid artery intima-media wall thickness (IMT) and flow-mediated endothelium-dependent vasodilatation (FMD) in a patients with RA, in context with clinical and laboratory measurements. Fifty-two patients with RA and 30 matched healthy controls without clinically evident CV disease were studied. Brachial and carotid ultrasonography was performed to determine FMD and IMT, respectively. We also assayed immunological, inflammatory and metabolic laboratory markers. IMT was significantly higher in RA patients (1.00 ± 0.16 mm) patients than in controls (0.89 ± 0.13 mm) (P = 0.001). FMD was significantly lower in RA (9.16 ± 7.03) as compared to controls (12.60 ± 5.49) (p = 0.005). RA patients had significant positive correlations between erythrocyte sedimentation rate (ESR) (r=0.395 p = 0.021) and IMT and negative correlation between visual analog scale (VAS) (r= -0.311, p= 0.025) and IMT. RA patients who used low doses of corticosteroids have, statistically, significantly better FMD, than those who do not use corticosteroids. Linear regression analysis revealed that IMT was related to tender joint count (p = 0.008), VAS (p < 0.001), ESR (p = 0.048) and total cholesterol/high density lipoprotein cholesterol ratio (p = 0.039). In patients with RA, FMD was impaired and IMT was increased, indicating early endothelial dysfunction and accelerated atherosclerosis. Early treatment of disease may reduce the risk of atherosclerosis in RA.
    VASA.: Zeitschrift für Gefässkrankheiten. Journal for vascular diseases 09/2012; 41(5):343-51. · 1.01 Impact Factor
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    ABSTRACT: Research on the effects of homocysteine on the vascular wall, especially in endothelial and smooth muscle cells, has indicated that increased homocysteine levels lead to cellular stress and cell damage. Considering the adverse effects of homocysteine on vascular function and the role of oxidative stress in these mechanisms, the aim of this study was to estimate the influence of different homocysteine isoforms on cardiac contractility, coronary flow, and oxidative stress markers in isolated rat heart. The hearts of male Wistar albino rats (n = 36, age 8 weeks, body mass 180-200 g), were excised and retrogradely perfused according to the Langendorff technique at a constant perfusion pressure (70 cmH(2)O) and administered with three isoforms of 10 μM homocysteine [DL-Hcy, DL-Hcy thiolactone-hydrochloride (TLHC) and L-Hcy TLHC). After the insertion and placement of the sensor in the left ventricle, the parameters of heart function: maximum rate of pressure development in the left ventricle (dP/dt max), minimum rate of pressure development in the left ventricle (dP/dt min), systolic left ventricular pressure (SLVP), diastolic left ventricular pressure (DLVP), mean blood pressure (MBP) and heart rate (HR)] were continuously registered. Flowmetry was used to evaluate the coronary flow. Markers of oxidative stress: index of lipid peroxidation measured as TBARS, nitric oxide measured through nitrites (NO(2) (-)), superoxide anion radical (O(2) (-)), and hydrogen peroxide (H(2)O(2)) in the coronary venous effluent were assessed spectrophotometrically. Our results showed that administration of Hcy compounds in concentration of 10 μM induced depression of cardiac contractility, manifested by a decrease in dp/dt max after administration of any Hcy compound, decrease in dp/dt min after administration of L-Hcy TLHC, decrease in SLVP after administration of DL-Hcy TLHC and DL-Hcy, and the drop in CF after administration of any Hcy compound. Regarding the effects of Hcy on oxidative stress parameters, only L-Hcy TLHC significantly affected O(2) (-) release. L-Hcy TLHC showed a cardiotoxic effect by affecting heart contractility, but surprisingly, it decreased the release of O(2) (-).
    Molecular and Cellular Biochemistry 07/2012; 370(1-2):59-67. · 2.33 Impact Factor
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    ABSTRACT: 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, O(2)(-), H(2)O(2) 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.
    European Surgical Research 06/2012; 48(4):200-7. · 0.75 Impact Factor
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    ABSTRACT: The aims of our study were to assess the redox state of adolescent athletes and non-athletes both at rest and after acute exposure to physical load and to find relations between parameters of redox state and morphofunctional characteristics of subjects. 58 young handball players and 37 non-athletes were subjected to body composition analysis, measuring of maximal oxygen consumption and blood sampling immediately before and after a maximal progressive exercise test. At rest, athletes had significantly higher superoxide dismutase (SOD) and catalase (CAT) activity, higher levels of glutathione (GSH) and nitric oxide (NO) and lower levels of lipid peroxidation (TBARS) compared with non-athletes. A maximal exercise test induced statistically significant rise of superoxide anion radical (O2-), hydrogen peroxide (H2O2) and NO levels in non-athletes, while TBARS levels decreased. Athletes experienced the fall in NO levels and the fall in CAT activity. After exercise, athletes had significantly lower levels of O2- compared with non-athletes. Two way repeated measures ANOVA showed that the response of O2-, NO and TBARS to the exercise test was dependent on the sports engagement (training experience) of subjects. Significant correlations between morphofunctional and redox parameters were found. These results suggest that physical fitness affects redox homeostasis.
    General Physiology and Biophysics 06/2012; 31(2):211-9. · 0.85 Impact Factor
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    ABSTRACT: Regular training has been claimed to increase the activity of antioxidant enzymes and, consequently, augments the resistance to oxidative stress; however, large volumes of training performed by elite sportsmen could lead to a chronic oxidative stress state. The aim of our study was to assess the oxidative status of elite athletes at the beginning of the preparatory and the beginning of the competition training phases, so that the influence of three months of programmed physical activity on redox status could be determined. The chronic effects of exercise on the redox state of the athletes were compared to the effects of a single bout of karate training. Thirty elite karate athletes, 16-30 years old, were subjected to maximal graded exercise test to estimate their aerobic capacity; blood sampling was also performed to measure levels of superoxide anion radical (O₂⁻), hydrogen peroxide (H₂O₂), superoxide dismutase activity (SOD) and catalase activity (CAT). The only significant change after the three-month training process was found in the significantly decreased CAT activity (X ± SE: 7.95 ± 0.13 U/g Hb × 10³ in the preparatory period, 6.65 ± 0.28 U/g Hb × 10³ in the competition stage; P < 0.01). After a single karate training session, there was statistically significant decrease of O₂⁻(X ± SE: 32.7 ± 4.9 nmol/ml in the preparatory period, 24.5 ± 2.5 nmol/ml in the competition stage; P < 0.05) and increase of H₂O₂(X ± SE: 11.8 ± 1.0 nmol/ml in the preparatory period, 14.2 ± 0.9 nmol/ml in the competition stage; P < 0.01), as well as significant CAT increase (X ± SE: 6.6 ± 0.6 U/g Hb × 10³ in the preparatory period, 8.5 ± 0.5 U/g Hb × 10³ in the competition stage; P < 0.05). Although the three-month training process induced, at the first sight, negative changes in the redox state, expressed through the decrease in CAT activity, adequate response of the antioxidant system of our athletes to acute exercise was preserved.
    The Chinese journal of physiology 02/2012; 55(1):8-15. · 0.75 Impact Factor
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    ABSTRACT: Тo examine the effects of nitroglycerine on portal vein haemodynamics and oxidative stress in patients with portal hypertension. Thirty healthy controls and 39 patients with clinically verified portal hypertension and increased vascular resistance participated in the study. Liver diameters, portal diameters and portal flow velocities were recorded using color flow imaging/pulsed Doppler detection. Cross-section area, portal flow and index of vascular resistance were calculated. In collected blood samples, superoxide anion radical (O(2) (-)), hydrogen peroxide (H(2)O(2)), index of lipid peroxidation (measured as TBARS) and nitric oxide (NO) as a marker of endothelial response (measured as nitrite-NO(2) (-)) were determined. Time-dependent analysis was performed at basal state and in 10th and 15th min after nitroglycerine (sublingual 0.5 mg) administration. Oxidative stress parameters changed significantly during the study. H(2)O(2) decreased at the end of study, probably via O(2) (-) mediated disassembling in Haber Weiss and Fenton reaction; O(2) (-) increased significantly probably due to increased diameter and tension and decreased shear rate level. Consequently O(2) (-) and H(2)O(2) degradation products, like hydroxyl radical, initiated lipid peroxidation. Increased blood flow was to some extent lower in patients than in controls due to double paradoxes, flow velocity decreased, shear rate decreased significantly indicating non Newtonian characteristics of portal blood flow. This pilot study could be a starting point for further investigation and possible implementation of some antioxidants in the treatment of portal hypertension.
    World Journal of Gastroenterology 01/2012; 18(4):331-9. · 2.55 Impact Factor
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    ABSTRACT: Taken into consideration limited data about effects of palladium on cardiovascular system, the aim of our study was to compare toxicity of inorganic and organic palladium compounds on the isolated rat heart. The hearts (total number n=30, 6 for each experimental group) excised from Wistar albino rats, male sex, age 8 weeks, and body mass 180-200 g, were retrogradely perfused according to the Langendorff technique at constant perfusion pressure (70 cm H2O). After the insertion of sensor in the left ventricle, the parameters of heart function: maximum rate of left ventricular pressure development (dP/dt max), systolic left ventricular pressure (SLVP), diastolic left ventricular pressure (DLVP), mean blood pressure (MBP) and heart rate (HR)), were continuously registered. The experiments were performed during control conditions, and in the presence of perfusion with incresing concentration of the following: (triethanolamine (TEA), triethanolamine acetate (TEAA), palladium(II)chloride (PdCl2), and trans-dichlorobis(triethanolamine-N)palladium(II) complex (trans-[PdCl2(TEA)2])) started every 30 minutes (30, 60, 90, 120 minute). dP/dt max was not affected significantly by either TEAA, TEA, PdCl2 or Pd complex. SLVP was, also, not affected significantly by either TEAA, TEA, PdCl2, or Pd complex. DLVP was significantly decreased by both TEAA and PdCl2, while TEA and Pd complex did not show significant effect. MBP was significantly decreased only by PdCl2, while TEAA, TEA and Pd complex did not show significant effect. HR was significantly decreased by all compounds- PdCl2, TEAA, TEA and Pd complex. In our study, inorganic palladium compound (PdCl2) induced clear depression of the isolated rat heart contractility, manifested as drop in diastolic and mean blood pressure , and as decrease of the heart rate. On the other hand, it seems that palladium, when bound in an organic compound (linked to TEA in Pd complex), does not contribute significantly to cardio-toxicity in our experimental conditions.
    Medicinal chemistry (Shāriqah (United Arab Emirates)) 01/2012; 8(1):9-13. · 1.64 Impact Factor
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    ABSTRACT: The purpose of this study was to assess the influence of sport-specific and nonspecific bouts of exercise on athletes' redox state. Blood samples were collected from 14 handball players immediately before and after graded exercise test on the cycle ergometer and handball training. Levels of superoxide anion radical (O(2) (-)), hydrogen peroxide (H(2)O(2)), nitrites (NO(2) (-)) as markers of nitric oxide, index of lipid peroxidation (TBARs), glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) activity were determined. Exercise intensity was assessed by a system for heart rate (HR) monitoring. Average athletes' HR was not significantly different between protocols, but protocols differed in total time and time and percentage of time that athletes spent in every HR zone. The laboratory exercise test induced a significant increase of H(2)O(2) and TBARs as well as the decrease of the SOD and CAT activity, while after specific handball training, levels of NO(2) (-) were increased and SOD activity decreased. It seems that unaccustomed short intensive physical activity may induce oxidative stress in trained athletes, while sport-specific activity of longer duration and proper warm-up period may not. Further research should show whether the change of protocol testing and the implementation of various supplementations and manual methods can affect the redox equilibrium.
    Oxidative Medicine and Cellular Longevity 01/2012; 2012:805850.
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    ABSTRACT: The true prevalence of mitral valve prolapsus (MVP) is not known due to implementation of diferential exploration techniques and diagnostic criteria. It varies from the very low 0.4% to the very high 35%, in respect to gender and age. According to the international data, MVP prevalence is estimated to be about 1-2% among children and 5-15% among adolescents. The objective of this study was to determine the potential new exact method for MVP diagnostics in children and adolescents, comparable to the "golden standard". This study summarizes results generated through general check-ups of 2018 school children, ages 7-19, 1049 females and 969 males. Diagnosis by method of auscultation with electronic stethoscope and phonocardiographic analysis of digitalized audio file, compared to echocardiographically confirmed MVP indicates that the accuracy of the data gathered by usage of electronic stethoscope, in comparison to the golden standard (echocardiography) on the level of trust, is 0.74 and 0.72 and, accordingly, 0.80 and 0.77. Statistical analysis demonstrated there was no difference in MVP morbidity as related to gender, enabling interpolation of the generated data for children of both genders, which indicated that the prevalence of MVP among children ages 7-19 was 3%, whereas in children ages 10-18 it increased linearly with age and peak of 18% at the age of 16. Our results showed that this new method could provide additional reliability and comfort during evaluation of MVP.
    Adaptive Medicine. 01/2012; 4(4):224-232.