11 research outputs found
Synthesis of gold nanoparticles using aldehyde functionalized levan as reducing agent
In this work, gold nanoparticles (AuNPs) were synthesized in aqueous solution by aldehyde functionalized microbial polysaccharide levan as a reducing agent. Resulting nanoparticles were characterized by UV-Vis spectroscopy and by particle size analysis
Synthesis of gold nanoparticles using aldehyde functionalized levan as reducing agent
In this work, gold nanoparticles (AuNPs) were synthesized in aqueous solution by aldehyde functionalized microbial polysaccharide levan as a reducing agent. Resulting nanoparticles were characterized by UV-Vis spectroscopy and by particle size analysis
The effects of acute hyperhomocysteinemia induced by DL-homocysteine or DL-homocysteine thiolactone on serum biochemical parameters, plasma antioxidant enzyme and cardiac acetylcholinesterase activities in the rat
The aim of this study was to assess the effects of DL-homocysteine (DL-Hcy) and DL-homocysteine thiolactone (DL-Hcy TLHC) on selected serum biochemical parameters, markers of oxidative stress and the activities of antioxidant enzymes (catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD)) in the plasma, as well as on acetylcholinesterase (AChE) activity in the cardiac tissue homogenate in the rat. Male Wistar rats were divided into three groups as follows: control group (1 mL 0.9% NaCl, intraperitoneal (i.p.) injection), DL-Hcy group (8 mmol/kg body mass (b.m.), i.p.) or DL-Hcy TLHC group (8 mmol/kg b.m., i.p.). One hour after administration, the rats were euthanized, whole blood was collected for biochemical analysis, and the heart was excised. Following the i.p. administration of DL-Hcy and DL-Hcy TLHC, the activities of antioxidant enzymes were mostly significantly increased, while plasma malondialdehyde (MDA) was decreased. Administration of DL-Hcy and DL-Hcy TLHC significantly inhibited AChE activity in rat cardiac tissue. Our findings suggest that DL-Hcy and DL-Hcy TLHC exerted prooxidant effects; however, the decrease in MDA points to an inverse response to the increase in antioxidant enzyme activities. While both substances inhibited AChE activity in rat cardiac tissue, DL-Hcy TLHC induced stronger effects than DL-Hcy
Redox Parameters in Blood of Thyroid Cancer Patients After the Radioiodine Ablation
The radioactive iodine (I-131) ablation is a well-accepted treatment modality for differentiated thyroid cancer patients. Unfortunately, the radiation induces the oxidative stress and damages cells and tissues, simultaneously activating the mechanisms of antioxidative defense. Since the mechanisms of those processes are not completely known, we wanted to examine the changes in the most important reactive oxygen species and antioxidative components, as well as their correlation and significance for lipid peroxidation. Our results showed that the level of thiobarbituric acid reactive substances was increased during the first 30 days after the radiotherapy. Among antioxidant components, superoxide dismutase was increased in the 3rd and 30th day; catalase in 7th and reduced glutathione in 3rd and 7th day after the radiotherapy. As regards the prooxidants, the reduction of hydrogen peroxide (H2O2) was recorded in 7th and 30th day, and superoxide anion radical (O-2(center dot-)) was unchanged after the exposure to I-131. These results indicate that differentiated thyroid cancer patients are under constant oxidative stress despite the observed increase in antioxidative and reduction in prooxidative parameters. The understanding of these early processes is important since their progress determines the latter effects of I-131 therapy
Comparative analysis of audiometric and impedancemetric findings in workers exposed to the effects of various duration industrial noise
Background/Aim. Industrial noise is produced in workshops due to factory machinery and tools used in technological processes. It has detrimental effect to primarily the organ of the sense of hearing, thus damaging hearing in oversensitive subjects. The aim of the study was to perform a detailed analysis of audiometric and, especially, impedancemetric parameters in workers exposed to the effects of industrial noise of various duration, as well as to determine similarities and differences in workers with differences in sensitivity to damaging effects of noise. Methods. The study included a homogenous group of 173 industrial workers involved in the same department of a huge workshop named 'Kovačica' exposed to noise level above a threshold intensity, and divided into three groups: the group I of 116 workers (232 ears) exposed to noise for 8 h in the workshop 'Kovačica', the group II of 41 workers (82 ears) exposed to noise only half of the working time, and the group III of 16 workers (32 ears) exposed to the same conditions and having the normal hearing sense. The group III served as a control group. Prior to the study any workers went through a thorough anamnesis and complete ORL examination, and then they were submitted to audiometric testing. The study included only the workers with no hearing damage due to diseases, injuries nor other detrimental factors in order to be sure that the hearing findings had been caused by industrial noise. Results. The results obtained by audiometric testing showed that 90.75% of the workers had hearing damage of various degrees, while 9.25 % of the workers had regular hearing although had been exposed to the same conditions. More severe hearing damage was revealed in the workers of the group I. Tympanometricly, in most ears of the group I workers (65.52%) a compliance value was found to be more than 0.9 cm3, while in the majority of those of the group II (59.75%) a compliance value was in the range from 0.5 to 0.9 cm3. In the workers of the group III with no hearing damage, a compliance value for any ears was in the range from 0.1 to 0.9 cm3. Mean value of threshold reflex (98.56 dB) at 500 Hz and 1 000 Hz in the group I was increased as compared with the group II (95.6 dB) and the group III (84.38 dB). At higher frequencies, 2 000 and 4 000 Hz, threshold reflex was increased in the group I (99.05 dB), and in the group II (97.6 dB) as compared with the group III (86.4 dB). The amplitude of stapedic reflex was lowest in the group I, while mean values of amplitude at 500, 1 000, 2 000 and at 4 000 Hz were 2.31, 1.38, 1 and 0.3, respectively. In the group II mean values of amplitude at 500, 1 000, 2 000 and 4 000 Hz were 2.52, 1.80, 1.30 and 0.5, respectively. In the group III mean values of amplitude at 500, 1 000, 2 000 and at 4 000 Hz were 2.36, 2.45, 2.5 and 2.08, respectively. By measuring input (rising) and output angles it was revealed that most ears of the workers in the groups I and II had rising angle ranging from 41 to 50o, and in the workers with no hearing loss from 31 to 50o. In the majority of the ears of the groups I and II outlet angle was in the range from 16 to 35o, and in the workers with no hearing damage from 26 to 35o. Conclusion. By audiometric and impedancemetric examinations it was determined that for the sense of hearing it is significant not only a threshold hearing expressed in the audiometric curve at various frequencies, but also a threshold of unpleasantness and pain under higher intensities shown by the occurrence of stapedic reflex. The less hearing field between threshold hearing and threshold acoustic reflex is, the less capabilities of hearing perception due to the occurrence of recruitment
Oxidative stress and nitrite dynamics under maximal load in elite athletes: relation to sport type
Maximal workload in elite athletes induces increased generation of reactive oxygen/nitrogen species (RONS) and oxidative stress, but the dynamics of RONS production are not fully explored. The aim of our study was to examine the effects of long-term engagement in sports with different energy requirements (aerobic, anaerobic, and aerobic/anaerobic) on oxidative stress parameters during progressive exercise test. Concentrations of lactates, nitric oxide (NO) measured through stabile end product-nitrites (NO(2) (-)), superoxide anion radical (O(2) (aEuro cent a')), and thiobarbituric reactive substances (TBARS) as index of lipid peroxidation were determined in rest, after maximal workload, and at 4 and 10th min of recovery in blood plasma of top level competitors in rowing, cycling, and taekwondo. Results showed that sportmen had similar concentrations of lactates and O(2) (aEuro cent a') in rest. Nitrite concentrations in rest were the lowest in taekwondo fighters, while rowers had the highest levels among examined groups. The order of magnitude for TBARS level in the rest was bicycling > taekwondo > rowing. During exercise at maximal intensity, the concentration of lactate significantly elevated to similar levels in all tested sportsmen and they were persistently elevated during recovery period of 4 and 10 min. There were no significant changes in O(2) (aEuro cent a'), nitrite, and TBARS levels neither at the maximum intensity of exercise nor during the recovery period comparing to the rest period in examined individuals. Our results showed that long term different training strategies establish different basal nitrites and lipid peroxidation levels in sportmen. However, progressive exercise does not influence basal nitrite and oxidative stress parameters level neither at maximal load nor during the first 10 min of recovery in sportmen studied.Ministry of Science and Technical Development of the Republic of Serbia [175043
Effects of sulfur amino acids, sodium hydrogen sulfide and H2S in rats
Date: September 28-30, 2017, Pécs, Hungary
Redox status of pregnant women with thrombophilia
Background/Aim. Since the role of oxidative stress in the pathogenesis of thrombophilia in pregnancy has still not been clarified, the aim of the study was to assess the redox status of pregnant women with thrombophilia. Methods. The study involved 120 pregnant women divided into two groups: pregnant women with thrombophilia (n = 60) and women with normal pregnancy (n = 60). Blood samples for biochemical analysis were collected at the end of the first, second, and third trimester of pregnancy. Concentrations of hydrogen peroxide (H2O2), nitrites (NO2-), and the index of lipid peroxidation measured as thiobarbituric acid reactive substances (TBARS) were measured in plasma. Levels of reduced glutathione (GSH), activities of superoxide dismutase (SOD) and catalase (CAT) were measured in erythrocytes. Results. In women with thrombophilia, NO2- values were increased in the first and third trimester compared to healthy pregnant women (p < 0.05). The higher levels of TBARS and H2O2 were noticed in women with thrombophilia in the first trimester compared to healthy pregnant women (p < 0.05). The values of SOD and CAT were lower in women with thrombophilia in the third and GSH in the first trimester compared to the control group (p < 0.05). Conclusion. Our results suggest an increased generation of prooxidants in thrombophilia at the beginning of gestation, which declines as gestation progresses and reaches similar values as in normal pregnancy at the end of pregnancy. Generally viewed, pregnant women with thrombophilia was associated with impaired antioxidant capacity – activities of SOD and CAT were lower in the third and GSH in the first trimester compared to their values in healthy pregnant women
Comparison of the effects of different sulfur amino acids on cardiovascular system in male wistar rats
Joint meeting of national physiological societies : May 25-27, 2017, Subotica
Redox parameters in blood of thyroid cancer patients after the radioiodine ablation
The radioactive iodine (131I) ablation is a well-accepted treatment modality
for differentiated thyroid cancer patients. Unfortunately, the radiation
induces the oxidative stress and damages cells and tissues, simultaneously
activating the mechanisms of antioxidative defense. Since the mechanisms of
those processes are not completely known, we wanted to examine the changes in
the most important reactive oxygen species and antioxidative components, as
well as their correlation and significance for lipid peroxidation. Our
results showed that the level of thiobarbituric acid reactive substances was
increased during the first 30 days after the radiotherapy. Among antioxidant
components, superoxide dismutase was increased in the 3rd and 30th day;
catalase in 7th and reduced glutathione in 3rd and 7th day after the
radiotherapy. As regards the prooxidants, the reduction of hydrogen peroxide
(H2O2) was recorded in 7th and 30th day, and superoxide anion radical (O×-)
was unchanged after the exposure to 131I. These results indicate that
differentiated thyroid cancer patients are under constant oxidative stress
despite the observed increase in antioxidative and reduction in prooxidative
parameters. The understanding of these early processes is important since
their progress determines the latter effects of 131I therapy. [Project of the
Serbian Ministry of Education, Science and Technological Development, Grant
no. III41007 and Grant no. 175007