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Volume 53, Issue 4, 2025
Online ISSN: 2560-3310
ISSN: 0350-8773
Volume 53 , Issue 4, (2025)
Published: 30.06.2025.
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Contents
01.06.2015.
Professional paper
P300 event related potential application to cognitive status assessment of the patients with subclinical hypothyroidism
Disturbances of thyroid function are often accompanied by cognitive and affective disorders. Assessment of cognitive status in the patients with subclinical hypothyroidism represents a possibility for early diagnostics of cognitive impairment and timely introduction of necessary pharmacotherapy treatment. The aim of this study was to quantify whether there are P3 event related potential (ERP) deviations as electrophysiological markers of cognitive activity in patients with subclinical hypothyroidism. P300 potentials were examined in thirty patients with subclinical hypothyroidism and in 30 healthy subjects of the control group. P300 was recorded using the classic auditory oddball paradigm, with 20% of target and 80% of non-target stimuli. The results analysis showed a significantly longer latency P300 and reduced amplitude P300 in subjects with subclinical hypothyroidism compared to euthyroid subjects. There is also a statistically significant negative correlation between the results of a mini mental state examination and the P300 latency at Fz electrode (r= -0.47, p <0.01) and Cz electrode (r= -0.43, p =0.017). P300 ERP is important in the evaluation of patients with subclinical hypothyroidism, due to the sensitivity in the detection cognitive disorders.
M. Dejanovic, V. Ivetic, V. Nestorovic, Z. Milanovic, B. Bisevac, M. Miletic, M. Miric
01.06.2015.
Professional paper
the variability in P300 cognitive evoked potential amplitude in the auditory oddball paradigm
One of the best-studied responses of cognitive evoked potentials is a so-called “P300”, the late positive wave complex that occurs about 300-500 ms after the stimulus. It is obtained when the subject’s attention is focused on a signal that is rare, especially if the signal has a motivational or emotional meaning. In the study of P300 potential, we followed the variations of potential amplitude and latency, so the objective was to examine whether there is a difference in Fz and Cz amplitudes of auditory induced cognitive evoked P300 potential depending on the performance of oddball tasks, both in male and female subjects. The study included 60 subjects (30 female respondents and 30 male respondents). P300 potential is induced by the auditory "oddball" paradigm with 80% of non-target and 20% of target stimuli that are presented to the patient through headphones. The target tones are high tones of 2000 Hz. The standard, 1000 Hz tones the respondent should ignore but when he hears the target tones the respondent should press the button on the special handle. The value of Fz and Cz amplitudes both in male and female subjects obtained in the classical "oddball" paradigm when the subject reacted to the signal by pressing the key with the dominant (right) arm were statistically significantly lower (p>0,05) than the values of Fz and Cz amplitudes obtained when the key was pressed by the non-dominant hand. Based on this experiment it can be concluded that both in male and female subjects the performance of oddball tasks does not affect the amplitude of P300 cognitive evoked potentials.
B. Biševac, Lj. Popović, Z. Milanović, V. Nestorović, S. Smiljić, M. Dejanović, S. Filipović-Danić, V. Mitrović, M. Mirić
01.12.2014.
Professional paper
HLORINIŠUĆA AKTIVNOST SERUMSKE MIJELOPEROKSIDAZE U AKUTNOM ISHEMIČNOM MOŽDANOM UDARU
Uz tradicionalne faktore rizika smatra se da i inflamacija doprinosi nastanku ishemičnog moždanog udara (IMU). U toku inflamacije neutrofilni leukociti se degranulišu, kada može doći do oslobađanja njihovog enzima mijeloperoksidze (MPO) u ekstracelularni prostor. Osim peroksidazme MPO poseduje i hlorinišuću aktivnost kojom stvara hipohlornu kiselinu i dugoživeće oksidanse hloramine. U ovoj studiji je određivana hlorinišuća aktivnost MPO i koncentracija ukupnih hloramina u serumu. U studiju je bilo uključeno 29 pacijenata sa akutnim IMU, starosti 69.0 godina (64.2–78.0), i 25 ispitanika kontrolne grupe bez IMU, starosti 69.0 godina (67.0–72.0). Nađeno je da je u grupi sa IMU broj neutrofilnih leukocita u perifernoj krvi značajno veći od kontrolnih vrednosti (4.56±1.76 vs. 7.74±3.35 × 109/L, u kontrolnoj grupi i kod pacijenata; p<0.05). Takođe je i hlorinišuća aktivnost MPO seruma bila veća u grupi sa IMU (67.2 U/L vs. 92.3 U/L, kod kontrole i kod pacijenata; p<0.05). Iako je koncentracija ukupnih hloramina bila nešto veća kod IMU nego u kontrolnoj grupi, razlika nije bila statistički značajna (p=0.178). Aktivnost MPO je značajno korelirala sa koncentracijom triglicerida (p<0.05). Korelacija između hlorinišuće aktivnosti MPO i ukupnih hloramina nije bila značajna (p=0.402), dok su korelacije MPO aktivnosti i broja neutrofila (p=0.071) odnosno MPO aktivnosti i prisustva aritmije (p=0.094) bile nešto veće. Rezultati ove studije ukazuju da MPO verovatno ima ulogu u patogenezi IMU, što se delimično može zasnivati na hlorinaciji biološki značajnih molekula vaskularnog kompartmana.
M. Miric, I. Dragojevic, B. Kisic, B. Bisevac, S. Filipovic, J. Marjanovic, M. Dejanovic
01.01.2011.
Original scientific paper
EFFECTS OF DIFFERENT DOSES OF ZINC PREPARATION ON GLYCEMIA AND ANTIOXIDANT PARAMETERS IN EXPERIMENTALLY INDUCED DIABETIC RABBITS
Researches with micronutrients are getting more and more important in science and also in practice. In this view zinc, chromium, copper and selenium are having a special role in preventing micro- and macrovascular diabetic complications, as integral components of antioxidant enzymes (superoxide dismutase and glutathione peroxidase) and also as cofactor of enzymes and hormones involved in the metabolism of glucose and lipid. The aim of this study was to evaluate the effects different doses of zinc on glycemia and parameters of antioxidative defense: superoxide dismutase (SOD) and total antioxidant status (TAS), and correlation glycoregulation with antioxidant system of the alloxan-induced diabetic rabbits. The study was conducted on fourteen New Zealand rabbits of both sexes, weighing 2 to 3.5 kg. Experimental diabetes was induced in rabbits by intravenous injection of alloxan (80 mg /kg BW). Three weeks after induced experimental diabetes, rabbits were treated orally appropriate doses of chelated zinc: I dose - 15 mg, after a washout period (10 t ), II dose - 25 mg, af- 1/2 ter a washout period, III dose - 50 mg. Blood samples were taken at specific time intervals: before alloxan induced diabetes, after alloxan induced diabetes, after application the first dose of 15 mg of zinc, after application of a second dose of 25 mg of zinc, after application of third dose of 50 mg of zinc. The zinc preparation did not cause a statistically significant reduction in serum glucose level when administered in single doses 15, 25 and 50 mg in experimentally induced diabetic rabbits. However, the activity of superoxide dismutase (SOD) was significantly increased after single dose preparations of zinc at a dose 15 mg (p<0,05), 25 mg (p<0,001) and 50 mg (p<0,001) in relation to the activity recorded before the application of zinc. Also, after the application first, second, and than third dose of zinc in diabetic rabbits was recorded statistically significant increase of TAS in relation to the value recorded before the application of zinc (p<0,001). Glucose concentrations negatively correlated with superoxide dismutase activity. This indicates that oral application of zinc preparation can reduce the harmful effects of oxidative stress in diabetes.
Z. Stanojević, R. Mitić, M. Stanić, M. Miletić, D. Valjarević, S. Hadžistević, M. Dejanović
01.12.2009.
Original scientific paper
FUNCTIONAL ASYMMETRY OF BRAIN AND POTENTIALS P300
In neurophysiology the concept of lateralization of brain hemisphere functions is related to the existence of differences in their functioning. The aim of the research was to determine for the right-handed females whether there is a connection between the degree of lateralization of brain hemispheres and the variables of cognitive potential P300 (latency and amplitude). In 30 study participated 70 girls, age 20-23 years. In the first group where 29 strong expressed right-hand girls, in the second group 30 moderately expressed right hand girls, and in the third group 11 right-hand learned girls. The reserch workers were using the "oddball" paradigm with two tones: "standard" (90dB 1000Hz) and "expected-target" (90dB 2000Hz) for the registration of the P300 potential. The tones were binauraly presented in irregular intervals and irregular order. P300 evoked potentials were registered above Fz and Cz area. Results showed the cognitive P300 wave latency to be significantly shorter when responding with dominant hand in first group. P300 wave latency in girls from second group was a shorter with engagement of the right hand. Cognitive P300 potentials above the FZ and Cz regions àt the first group have a significantly shorter latency compared to the average latency of potentials registered in girls from second group. Cognitive P300 amplitude waves are higher above central regions independently of the hand used.
O. Ivetić, V. Vasić, N. Naumović, M. Dejanović