TY  - JOUR
AU  - Korać Jačić, Jelena
AU  - Nikolić, Ljiljana M.
AU  - Stanković, Dalibor M.
AU  - Opačić, Miloš
AU  - Dimitrijević, Milena
AU  - Savić, Danijela Z
AU  - Grguric-Sipka, Sanja
AU  - Spasojević, Ivan
AU  - Bogdanović Pristov, Jelena
PY  - 2020
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1344
AB  - Upon release in response to stress, epinephrine (Epi) may interact with labile iron pool in human plasma with potentially important (patho)physiological consequences. We have shown that Epi and Fe3+ build stable 1:1 high-spin bidentate complex at physiological pH, and that Epi does not undergo degradation in the presence of iron. However, the interactions of Epi with the more soluble Fe2+, and the impact of iron on biological activity of Epi are still not known. Herein we showed that Epi and Fe2+ build colorless complex which is stable under anaerobic conditions. In the presence of O-2, Epi promoted the oxidation of Fe2+ and the formation of Epi-Fe3+ complex. Cyclic voltammetry showed that mid-point potential of Epi-Fe2+ complex is very low (-582 mV vs. standard hydrogen electrode), which explains catalyzed oxidation of Fe2+. Next, we examined the impact of iron binding on biological performance of Epi using patch clamping in cell culture with constitutive expression of adrenergic receptors. Epi alone evoked an increase of outward currents, whereas Epi in the complex with Fe3+ did not. This implies that the binding of Epi to adrenergic receptors and their activation is prevented by the formation of complex with iron. Pro-oxidative activity of Epi-Fe2+ complex may represent a link between chronic stress and cardiovascular problems. On the other hand, labile iron could serve as a modulator of biological activity of ligands. Such interactions may be important in human pathologies that are related to iron overload or deficiency.
PB  - Elsevier Science Inc, New York
T2  - Free Radical Biology and Medicine
T1  - Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors
EP  - 127
SP  - 123
VL  - 148
DO  - 10.1016/j.freeradbiomed.2020.01.001
ER  - 

@article{
author = "Korać Jačić, Jelena and Nikolić, Ljiljana M. and Stanković, Dalibor M. and Opačić, Miloš and Dimitrijević, Milena and Savić, Danijela Z and Grguric-Sipka, Sanja and Spasojević, Ivan and Bogdanović Pristov, Jelena",
year = "2020",
abstract = "Upon release in response to stress, epinephrine (Epi) may interact with labile iron pool in human plasma with potentially important (patho)physiological consequences. We have shown that Epi and Fe3+ build stable 1:1 high-spin bidentate complex at physiological pH, and that Epi does not undergo degradation in the presence of iron. However, the interactions of Epi with the more soluble Fe2+, and the impact of iron on biological activity of Epi are still not known. Herein we showed that Epi and Fe2+ build colorless complex which is stable under anaerobic conditions. In the presence of O-2, Epi promoted the oxidation of Fe2+ and the formation of Epi-Fe3+ complex. Cyclic voltammetry showed that mid-point potential of Epi-Fe2+ complex is very low (-582 mV vs. standard hydrogen electrode), which explains catalyzed oxidation of Fe2+. Next, we examined the impact of iron binding on biological performance of Epi using patch clamping in cell culture with constitutive expression of adrenergic receptors. Epi alone evoked an increase of outward currents, whereas Epi in the complex with Fe3+ did not. This implies that the binding of Epi to adrenergic receptors and their activation is prevented by the formation of complex with iron. Pro-oxidative activity of Epi-Fe2+ complex may represent a link between chronic stress and cardiovascular problems. On the other hand, labile iron could serve as a modulator of biological activity of ligands. Such interactions may be important in human pathologies that are related to iron overload or deficiency.",
publisher = "Elsevier Science Inc, New York",
journal = "Free Radical Biology and Medicine",
title = "Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors",
pages = "127-123",
volume = "148",
doi = "10.1016/j.freeradbiomed.2020.01.001"
}

Korać Jačić, J., Nikolić, L. M., Stanković, D. M., Opačić, M., Dimitrijević, M., Savić, D. Z., Grguric-Sipka, S., Spasojević, I.,& Bogdanović Pristov, J.. (2020). Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors. in Free Radical Biology and Medicine
Elsevier Science Inc, New York., 148, 123-127.
https://doi.org/10.1016/j.freeradbiomed.2020.01.001

Korać Jačić J, Nikolić LM, Stanković DM, Opačić M, Dimitrijević M, Savić DZ, Grguric-Sipka S, Spasojević I, Bogdanović Pristov J. Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors. in Free Radical Biology and Medicine. 2020;148:123-127.
doi:10.1016/j.freeradbiomed.2020.01.001 .

Korać Jačić, Jelena, Nikolić, Ljiljana M., Stanković, Dalibor M., Opačić, Miloš, Dimitrijević, Milena, Savić, Danijela Z, Grguric-Sipka, Sanja, Spasojević, Ivan, Bogdanović Pristov, Jelena, "Ferrous iron binding to epinephrine promotes the oxidation of iron and impedes activation of adrenergic receptors" in Free Radical Biology and Medicine, 148 (2020):123-127,
https://doi.org/10.1016/j.freeradbiomed.2020.01.001 . .

Spasić, S.,& Kesic, S.. (2019). Editorial: Nonlinearity in Living Systems: Theoretical and Practical Perspectives on Metrics of Physiological Signal Complexity. in Frontiers in Physiology
Frontiers Media Sa, Lausanne., 10.
https://doi.org/10.3389/fphys.2019.00298

Spasić S, Kesic S. Editorial: Nonlinearity in Living Systems: Theoretical and Practical Perspectives on Metrics of Physiological Signal Complexity. in Frontiers in Physiology. 2019;10.
doi:10.3389/fphys.2019.00298 .

Spasić, Slađana, Kesic, Srdjan, "Editorial: Nonlinearity in Living Systems: Theoretical and Practical Perspectives on Metrics of Physiological Signal Complexity" in Frontiers in Physiology, 10 (2019),
https://doi.org/10.3389/fphys.2019.00298 . .

TY  - JOUR
AU  - Kesic, Srdjan
AU  - Spasić, Slađana
PY  - 2016
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1006
AB  - Background and objective: For more than 20 years, Higuchi's fractal dimension (HFD), as a nonlinear method, has occupied an important place in the analysis of biological signals. The use of HFD has evolved from EEG and single neuron activity analysis to the most recent application in automated assessments of different clinical conditions. Our objective is to provide an updated review of the HFD method applied in basic and clinical neurophysiological research. Methods: This article summarizes and critically reviews a broad literature and major findings concerning the applications of HFD for measuring the complexity of neuronal activity during different neurophysiological conditions. The source of information used in this review comes from the PubMed, Scopus, Google Scholar and IEEE Xplore Digital Library databases. Results: The review process substantiated the significance, advantages and shortcomings of HFD application within all key areas of basic and clinical neurophysiology. Therefore, the paper discusses HFD application alone, combined with other linear or nonlinear measures, or as a part of automated methods for analyzing neurophysiological signals. Conclusions: The speed, accuracy and cost of applying the HFD method for research and medical diagnosis make it stand out from the widely used linear methods. However, only a combination of HFD with other nonlinear methods ensures reliable and accurate analysis of a wide range of neurophysiological signals.
PB  - Elsevier Ireland Ltd, Clare
T2  - Computer Methods and Programs in Biomedicine
T1  - Application of Higuchi's fractal dimension from basic to clinical neurophysiology: A review
EP  - 70
SP  - 55
VL  - 133
DO  - 10.1016/j.cmpb.2016.05.014
ER  - 

@article{
author = "Kesic, Srdjan and Spasić, Slađana",
year = "2016",
abstract = "Background and objective: For more than 20 years, Higuchi's fractal dimension (HFD), as a nonlinear method, has occupied an important place in the analysis of biological signals. The use of HFD has evolved from EEG and single neuron activity analysis to the most recent application in automated assessments of different clinical conditions. Our objective is to provide an updated review of the HFD method applied in basic and clinical neurophysiological research. Methods: This article summarizes and critically reviews a broad literature and major findings concerning the applications of HFD for measuring the complexity of neuronal activity during different neurophysiological conditions. The source of information used in this review comes from the PubMed, Scopus, Google Scholar and IEEE Xplore Digital Library databases. Results: The review process substantiated the significance, advantages and shortcomings of HFD application within all key areas of basic and clinical neurophysiology. Therefore, the paper discusses HFD application alone, combined with other linear or nonlinear measures, or as a part of automated methods for analyzing neurophysiological signals. Conclusions: The speed, accuracy and cost of applying the HFD method for research and medical diagnosis make it stand out from the widely used linear methods. However, only a combination of HFD with other nonlinear methods ensures reliable and accurate analysis of a wide range of neurophysiological signals.",
publisher = "Elsevier Ireland Ltd, Clare",
journal = "Computer Methods and Programs in Biomedicine",
title = "Application of Higuchi's fractal dimension from basic to clinical neurophysiology: A review",
pages = "70-55",
volume = "133",
doi = "10.1016/j.cmpb.2016.05.014"
}

Kesic, S.,& Spasić, S.. (2016). Application of Higuchi's fractal dimension from basic to clinical neurophysiology: A review. in Computer Methods and Programs in Biomedicine
Elsevier Ireland Ltd, Clare., 133, 55-70.
https://doi.org/10.1016/j.cmpb.2016.05.014

Kesic S, Spasić S. Application of Higuchi's fractal dimension from basic to clinical neurophysiology: A review. in Computer Methods and Programs in Biomedicine. 2016;133:55-70.
doi:10.1016/j.cmpb.2016.05.014 .

Kesic, Srdjan, Spasić, Slađana, "Application of Higuchi's fractal dimension from basic to clinical neurophysiology: A review" in Computer Methods and Programs in Biomedicine, 133 (2016):55-70,
https://doi.org/10.1016/j.cmpb.2016.05.014 . .

TY  - JOUR
AU  - Spasić, Slađana
AU  - Kesic, Srdjan
AU  - Stojadinović, Gordana
AU  - Petković, Branka
AU  - Todorović, Dajana
PY  - 2015
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/830
AB  - To study the influence of a static magnetic field (SMF, 2 mT) and extremely low frequency magnetic field (ELF MF, 50 Hz, 2 mT) on the neuronal population activity, the experiments were performed on adult longhorn beetles Morimus funereus (Coleoptera, Cerambycidae). Based on a wavelet analysis of the local field potentials (LFPs), our study showed for the first time that the effects of prolonged and repeated exposure to the ELF MF on the LFPs were irreversible within investigated time frame. The relative wavelet energy (RWE) of 4-8 Hz frequency band was significantly increased after sine ELF MF (SnMF)/square ELF MF (SqMF) in comparison to the control value. The RWE of slower oscillations (1-2 Hz) was significantly decreased after the repeated exposures to either SnMF or SqMF. The SqMF induced decreasing of the faster waves in the range of 64-128 Hz. However, we did not prove with presented methods that exposure to the SMF for 5 min produces any effects on the neuronal population activity. This study has proved the wavelet transform as a valuable tool for measuring the effects of SMF and ELF MF on the neuronal population activity in M. funereus antennal lobe.
PB  - Elsevier Science Inc, New York
T2  - Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology
T1  - Effects of the static and ELF magnetic fields on the neuronal population activity in Morimus funereus (Coleoptera, Cerambycidae) antennal lobe revealed by wavelet analysis
EP  - 35
SP  - 27
VL  - 181
DO  - 10.1016/j.cbpa.2014.11.018
ER  - 

@article{
author = "Spasić, Slađana and Kesic, Srdjan and Stojadinović, Gordana and Petković, Branka and Todorović, Dajana",
year = "2015",
abstract = "To study the influence of a static magnetic field (SMF, 2 mT) and extremely low frequency magnetic field (ELF MF, 50 Hz, 2 mT) on the neuronal population activity, the experiments were performed on adult longhorn beetles Morimus funereus (Coleoptera, Cerambycidae). Based on a wavelet analysis of the local field potentials (LFPs), our study showed for the first time that the effects of prolonged and repeated exposure to the ELF MF on the LFPs were irreversible within investigated time frame. The relative wavelet energy (RWE) of 4-8 Hz frequency band was significantly increased after sine ELF MF (SnMF)/square ELF MF (SqMF) in comparison to the control value. The RWE of slower oscillations (1-2 Hz) was significantly decreased after the repeated exposures to either SnMF or SqMF. The SqMF induced decreasing of the faster waves in the range of 64-128 Hz. However, we did not prove with presented methods that exposure to the SMF for 5 min produces any effects on the neuronal population activity. This study has proved the wavelet transform as a valuable tool for measuring the effects of SMF and ELF MF on the neuronal population activity in M. funereus antennal lobe.",
publisher = "Elsevier Science Inc, New York",
journal = "Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology",
title = "Effects of the static and ELF magnetic fields on the neuronal population activity in Morimus funereus (Coleoptera, Cerambycidae) antennal lobe revealed by wavelet analysis",
pages = "35-27",
volume = "181",
doi = "10.1016/j.cbpa.2014.11.018"
}

Spasić, S., Kesic, S., Stojadinović, G., Petković, B.,& Todorović, D.. (2015). Effects of the static and ELF magnetic fields on the neuronal population activity in Morimus funereus (Coleoptera, Cerambycidae) antennal lobe revealed by wavelet analysis. in Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology
Elsevier Science Inc, New York., 181, 27-35.
https://doi.org/10.1016/j.cbpa.2014.11.018

Spasić S, Kesic S, Stojadinović G, Petković B, Todorović D. Effects of the static and ELF magnetic fields on the neuronal population activity in Morimus funereus (Coleoptera, Cerambycidae) antennal lobe revealed by wavelet analysis. in Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology. 2015;181:27-35.
doi:10.1016/j.cbpa.2014.11.018 .

Spasić, Slađana, Kesic, Srdjan, Stojadinović, Gordana, Petković, Branka, Todorović, Dajana, "Effects of the static and ELF magnetic fields on the neuronal population activity in Morimus funereus (Coleoptera, Cerambycidae) antennal lobe revealed by wavelet analysis" in Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology, 181 (2015):27-35,
https://doi.org/10.1016/j.cbpa.2014.11.018 . .

TY  - JOUR
AU  - Kesić, Srđan Ž.
AU  - Nikolić, Ljiljana
AU  - Janać, Branka
AU  - Spasić, Slađana
PY  - 2014
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/2398
AB  - The components of complex bioelectrical activity – action potential (AP), interspike interval (ISI) and the quiet interburst interval (IBI), along with the effects of 2.7 mT and 10 mT static magnetic fields, were identified and examined in the spontaneously active Br neuron of the subesophageal ganglion complex of the garden snail Helix pomatia by fractal analysis using Higuchi’s fractal dimension (FD). The normalized mean of the empirical FD distributions of bursting activity of the Br neuron were formed under different experimental conditions: before (Control), during (MF), and after exposure to the static magnetic field (AMF). Using the fractal analysis method for the first time, a separation of the AP, ISI and IBI components was successfully achieved. Our results show that fractal analysis with deconvolution of the normalized mean of the empirical FD distributions into Gaussian functions is a useful tool for revealing the effects of magnetic fields on the complexity of neuronal bioelectric activity and its AP, ISI and IBI components.
PB  - Serbian Biological Society
PB  - Institute for Biological Research "Siniša Stanković", Serbia
PB  - Serbian Biological Society, Institute for BFaculty of Biology, University of Belgrade
PB  - Department of Biology and Ecology, Faculty of Science, University of Novi Sad
PB  - Institute for the Application of Nuclear Energy
T2  - Archives of Biological Sciences
T1  - Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mT and 10 mT static magnetic fields on the complex bursting activity of the snail BR neuron
EP  - 572
IS  - 2
SP  - 563
VL  - 66
DO  - 10.2298/ABS1402563K
ER  - 

@article{
author = "Kesić, Srđan Ž. and Nikolić, Ljiljana and Janać, Branka and Spasić, Slađana",
year = "2014",
abstract = "The components of complex bioelectrical activity – action potential (AP), interspike interval (ISI) and the quiet interburst interval (IBI), along with the effects of 2.7 mT and 10 mT static magnetic fields, were identified and examined in the spontaneously active Br neuron of the subesophageal ganglion complex of the garden snail Helix pomatia by fractal analysis using Higuchi’s fractal dimension (FD). The normalized mean of the empirical FD distributions of bursting activity of the Br neuron were formed under different experimental conditions: before (Control), during (MF), and after exposure to the static magnetic field (AMF). Using the fractal analysis method for the first time, a separation of the AP, ISI and IBI components was successfully achieved. Our results show that fractal analysis with deconvolution of the normalized mean of the empirical FD distributions into Gaussian functions is a useful tool for revealing the effects of magnetic fields on the complexity of neuronal bioelectric activity and its AP, ISI and IBI components.",
publisher = "Serbian Biological Society, Institute for Biological Research "Siniša Stanković", Serbia, Serbian Biological Society, Institute for BFaculty of Biology, University of Belgrade, Department of Biology and Ecology, Faculty of Science, University of Novi Sad, Institute for the Application of Nuclear Energy",
journal = "Archives of Biological Sciences",
title = "Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mT and 10 mT static magnetic fields on the complex bursting activity of the snail BR neuron",
pages = "572-563",
number = "2",
volume = "66",
doi = "10.2298/ABS1402563K"
}

Kesić, S. Ž., Nikolić, L., Janać, B.,& Spasić, S.. (2014). Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mT and 10 mT static magnetic fields on the complex bursting activity of the snail BR neuron. in Archives of Biological Sciences
Serbian Biological Society., 66(2), 563-572.
https://doi.org/10.2298/ABS1402563K

Kesić SŽ, Nikolić L, Janać B, Spasić S. Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mT and 10 mT static magnetic fields on the complex bursting activity of the snail BR neuron. in Archives of Biological Sciences. 2014;66(2):563-572.
doi:10.2298/ABS1402563K .

Kesić, Srđan Ž., Nikolić, Ljiljana, Janać, Branka, Spasić, Slađana, "Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mT and 10 mT static magnetic fields on the complex bursting activity of the snail BR neuron" in Archives of Biological Sciences, 66, no. 2 (2014):563-572,
https://doi.org/10.2298/ABS1402563K . .

TY  - JOUR
AU  - Kesic, Srdjan
AU  - Nikolić, Ljiljana M.
AU  - Savić, Aleksandar G
AU  - Petković, Branka
AU  - Spasić, Slađana
PY  - 2014
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/786
AB  - Aim of this study was to investigate the application of normalized mean of the empirical Higuchi fractal dimension (FD) distributions, as a new approach to analyze the spontaneous bioelectrical activity of garden snail (Helix pomatia) Br neuron. The effect of ouabain on modulation of Br neuron bursting activity before and after the exposure to 10 mT static magnetic field (SMF) was observed by analyzing the following parameters: action potential (AP), interspike interval (ISI) and interbursting interval (IBI) components. Normalized mean of the empirical FD distributions were formed for the following experimental conditions: Control 1, Ouabain 1, Control 2, SMF 2, ASMF 2, Control 3, SMF 3 and Ouabain ASMF 3. Our main results have shown that ouabain without SMF induced increase in participation of AP and a decrease in participation of IBI components compared to the first control condition. However, in the presence of 10 mT SMF, ouabain-induced changes of measured parameters of Br neuron activity were less pronounced compared to the third control condition. We have shown that normalized mean of the empirical FD distributions is a useful method for detecting the changes in AP, ISI, and IBI components of complex bursting activity in altered physiological states.
PB  - General Physiol And Biophysics, Bratislava
T2  - General Physiology and Biophysics
T1  - Ouabain modulation of snail Br neuron bursting activity after the exposure to 10 mT static magnetic field revealed by Higuchi fractal dimension
EP  - 344
IS  - 3
SP  - 335
VL  - 33
DO  - 10.4149/gpb_2014010
ER  - 

@article{
author = "Kesic, Srdjan and Nikolić, Ljiljana M. and Savić, Aleksandar G and Petković, Branka and Spasić, Slađana",
year = "2014",
abstract = "Aim of this study was to investigate the application of normalized mean of the empirical Higuchi fractal dimension (FD) distributions, as a new approach to analyze the spontaneous bioelectrical activity of garden snail (Helix pomatia) Br neuron. The effect of ouabain on modulation of Br neuron bursting activity before and after the exposure to 10 mT static magnetic field (SMF) was observed by analyzing the following parameters: action potential (AP), interspike interval (ISI) and interbursting interval (IBI) components. Normalized mean of the empirical FD distributions were formed for the following experimental conditions: Control 1, Ouabain 1, Control 2, SMF 2, ASMF 2, Control 3, SMF 3 and Ouabain ASMF 3. Our main results have shown that ouabain without SMF induced increase in participation of AP and a decrease in participation of IBI components compared to the first control condition. However, in the presence of 10 mT SMF, ouabain-induced changes of measured parameters of Br neuron activity were less pronounced compared to the third control condition. We have shown that normalized mean of the empirical FD distributions is a useful method for detecting the changes in AP, ISI, and IBI components of complex bursting activity in altered physiological states.",
publisher = "General Physiol And Biophysics, Bratislava",
journal = "General Physiology and Biophysics",
title = "Ouabain modulation of snail Br neuron bursting activity after the exposure to 10 mT static magnetic field revealed by Higuchi fractal dimension",
pages = "344-335",
number = "3",
volume = "33",
doi = "10.4149/gpb_2014010"
}

Kesic, S., Nikolić, L. M., Savić, A. G., Petković, B.,& Spasić, S.. (2014). Ouabain modulation of snail Br neuron bursting activity after the exposure to 10 mT static magnetic field revealed by Higuchi fractal dimension. in General Physiology and Biophysics
General Physiol And Biophysics, Bratislava., 33(3), 335-344.
https://doi.org/10.4149/gpb_2014010

Kesic S, Nikolić LM, Savić AG, Petković B, Spasić S. Ouabain modulation of snail Br neuron bursting activity after the exposure to 10 mT static magnetic field revealed by Higuchi fractal dimension. in General Physiology and Biophysics. 2014;33(3):335-344.
doi:10.4149/gpb_2014010 .

Kesic, Srdjan, Nikolić, Ljiljana M., Savić, Aleksandar G, Petković, Branka, Spasić, Slađana, "Ouabain modulation of snail Br neuron bursting activity after the exposure to 10 mT static magnetic field revealed by Higuchi fractal dimension" in General Physiology and Biophysics, 33, no. 3 (2014):335-344,
https://doi.org/10.4149/gpb_2014010 . .

TY  - JOUR
AU  - Kesic, S.
AU  - Nikolić, Ljiljana M.
AU  - Janac, Branka
AU  - Spasić, Slađana
PY  - 2014
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/767
AB  - The components of complex bioelectrical activity - action potential (AP), interspike interval (ISI) and the quiet interburst interval (IBI), along with the effects of 2.7 mT and 10 mT static magnetic fields, were identified and examined in the spontaneously active Br neuron of the subesophageal ganglion complex of the garden snail Helix pomatia by fractal analysis using Higuchi's fractal dimension (FD). The normalized mean of the empirical FD distributions of bursting activity of the Br neuron were formed under different experimental conditions: before (Control), during (MF), and after exposure to the static magnetic field (AMF). Using the fractal analysis method for the first time, a separation of the AP, ISI and IBI components was successfully achieved. Our results show that fractal analysis with deconvolution of the normalized mean of the empirical FD distributions into Gaussian functions is a useful tool for revealing the effects of magnetic fields on the complexity of neuronal bioelectric activity and its AP, ISI and IBI components.
PB  - Srpsko biološko društvo, Beograd, i dr.
T2  - Archives of Biological Sciences
T1  - Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mt and 10 mt static magnetic fields on the complex bursting activity of the snail br neuron
EP  - 572
IS  - 2
SP  - 563
VL  - 66
DO  - 10.2298/ABS1402563K
ER  - 

@article{
author = "Kesic, S. and Nikolić, Ljiljana M. and Janac, Branka and Spasić, Slađana",
year = "2014",
abstract = "The components of complex bioelectrical activity - action potential (AP), interspike interval (ISI) and the quiet interburst interval (IBI), along with the effects of 2.7 mT and 10 mT static magnetic fields, were identified and examined in the spontaneously active Br neuron of the subesophageal ganglion complex of the garden snail Helix pomatia by fractal analysis using Higuchi's fractal dimension (FD). The normalized mean of the empirical FD distributions of bursting activity of the Br neuron were formed under different experimental conditions: before (Control), during (MF), and after exposure to the static magnetic field (AMF). Using the fractal analysis method for the first time, a separation of the AP, ISI and IBI components was successfully achieved. Our results show that fractal analysis with deconvolution of the normalized mean of the empirical FD distributions into Gaussian functions is a useful tool for revealing the effects of magnetic fields on the complexity of neuronal bioelectric activity and its AP, ISI and IBI components.",
publisher = "Srpsko biološko društvo, Beograd, i dr.",
journal = "Archives of Biological Sciences",
title = "Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mt and 10 mt static magnetic fields on the complex bursting activity of the snail br neuron",
pages = "572-563",
number = "2",
volume = "66",
doi = "10.2298/ABS1402563K"
}

Kesic, S., Nikolić, L. M., Janac, B.,& Spasić, S.. (2014). Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mt and 10 mt static magnetic fields on the complex bursting activity of the snail br neuron. in Archives of Biological Sciences
Srpsko biološko društvo, Beograd, i dr.., 66(2), 563-572.
https://doi.org/10.2298/ABS1402563K

Kesic S, Nikolić LM, Janac B, Spasić S. Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mt and 10 mt static magnetic fields on the complex bursting activity of the snail br neuron. in Archives of Biological Sciences. 2014;66(2):563-572.
doi:10.2298/ABS1402563K .

Kesic, S., Nikolić, Ljiljana M., Janac, Branka, Spasić, Slađana, "Using Higuchi’s fractal dimension in fine analysis of the effects of 2.7 mt and 10 mt static magnetic fields on the complex bursting activity of the snail br neuron" in Archives of Biological Sciences, 66, no. 2 (2014):563-572,
https://doi.org/10.2298/ABS1402563K . .

TY  - CONF
AU  - Spasić, Slađana
AU  - Savić, A.
AU  - Nikolic, L.
AU  - Budimir, Snežana M
AU  - Janosević, D.
AU  - Mitrović, Aleksandra Lj.
PY  - 2012
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/561
AB  - Significant contribution to understanding of complex biological systems emerged from application of fractal analysis. This paper presents a fractal analysis as one of many mathematical methods in the analysis of biological signals. Higuchi's fractal dimension is used in stationary and quasi-stationary bio-signals (EEG, ECoG) analysis and appropriately modified in the analysis of the bimodal pattern of neuronal activity as non-stationary signals.
C3  - 2012 20th Telecommunications Forum, TELFOR 2012 - Proceedings
T1  - Applications of Higuchi's fractal dimension in the Analysis of Biological Signals
EP  - 641
SP  - 639
DO  - 10.1109/TELFOR.2012.6419291
ER  - 

@conference{
author = "Spasić, Slađana and Savić, A. and Nikolic, L. and Budimir, Snežana M and Janosević, D. and Mitrović, Aleksandra Lj.",
year = "2012",
abstract = "Significant contribution to understanding of complex biological systems emerged from application of fractal analysis. This paper presents a fractal analysis as one of many mathematical methods in the analysis of biological signals. Higuchi's fractal dimension is used in stationary and quasi-stationary bio-signals (EEG, ECoG) analysis and appropriately modified in the analysis of the bimodal pattern of neuronal activity as non-stationary signals.",
journal = "2012 20th Telecommunications Forum, TELFOR 2012 - Proceedings",
title = "Applications of Higuchi's fractal dimension in the Analysis of Biological Signals",
pages = "641-639",
doi = "10.1109/TELFOR.2012.6419291"
}

Spasić, S., Savić, A., Nikolic, L., Budimir, S. M., Janosević, D.,& Mitrović, A. Lj.. (2012). Applications of Higuchi's fractal dimension in the Analysis of Biological Signals. in 2012 20th Telecommunications Forum, TELFOR 2012 - Proceedings, 639-641.
https://doi.org/10.1109/TELFOR.2012.6419291

Spasić S, Savić A, Nikolic L, Budimir SM, Janosević D, Mitrović AL. Applications of Higuchi's fractal dimension in the Analysis of Biological Signals. in 2012 20th Telecommunications Forum, TELFOR 2012 - Proceedings. 2012;:639-641.
doi:10.1109/TELFOR.2012.6419291 .

Spasić, Slađana, Savić, A., Nikolic, L., Budimir, Snežana M, Janosević, D., Mitrović, Aleksandra Lj., "Applications of Higuchi's fractal dimension in the Analysis of Biological Signals" in 2012 20th Telecommunications Forum, TELFOR 2012 - Proceedings (2012):639-641,
https://doi.org/10.1109/TELFOR.2012.6419291 . .

TY  - JOUR
AU  - Nikolić, Ljiljana M.
AU  - Todorović, Nataša
AU  - Zakrzewska, Joanna
AU  - Stanić, Marina
AU  - Raus, Snežana Z
AU  - Kalauzi, Aleksandar
AU  - Janac, Branka B
PY  - 2012
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/539
AB  - The spontaneously active Br neuron from the brain-subesophageal ganglion complex of the garden snail Helix pomatia rhythmically generates regular bursts of action potentials with quiescent intervals accompanied by slow oscillations of membrane potential. We examined the involvement of the Na+/K+ pump in modulating its bursting activity by applying a static magnetic field. Whole snail brains and Br neuron were exposed to the 10-mT static magnetic field for 15 min. Biochemical data showed that Na+/K+-ATPase activity increased almost twofold after exposure of snail brains to the static magnetic field. Similarly, P-31 NMR data revealed a trend of increasing ATP consumption and increase in intracellular pH mediated by the Na+/H+ exchanger in snail brains exposed to the static magnetic field. Importantly, current clamp recordings from the Br neuron confirmed the increase in activity of the Na+/K+ pump after exposure to the static magnetic field, as the magnitude of ouabain's effect measured on the membrane resting potential, action potential, and interspike interval duration was higher in neurons exposed to the magnetic field. Metabolic pathways through which the magnetic field influenced the Na+/K+ pump could involve phosphorylation and dephosphorylation, as blocking these processes abolished the effect of the static magnetic field.
PB  - Springer, New York
T2  - Journal of Comparative Physiology A-Neuroethology Sensory Neural and Behavioral Physiology
T1  - Involvement of Na+/K(+)pump in fine modulation of bursting activity of the snail Br neuron by 10 mT static magnetic field
EP  - 540
IS  - 7
SP  - 525
VL  - 198
DO  - 10.1007/s00359-012-0727-0
ER  - 

@article{
author = "Nikolić, Ljiljana M. and Todorović, Nataša and Zakrzewska, Joanna and Stanić, Marina and Raus, Snežana Z and Kalauzi, Aleksandar and Janac, Branka B",
year = "2012",
abstract = "The spontaneously active Br neuron from the brain-subesophageal ganglion complex of the garden snail Helix pomatia rhythmically generates regular bursts of action potentials with quiescent intervals accompanied by slow oscillations of membrane potential. We examined the involvement of the Na+/K+ pump in modulating its bursting activity by applying a static magnetic field. Whole snail brains and Br neuron were exposed to the 10-mT static magnetic field for 15 min. Biochemical data showed that Na+/K+-ATPase activity increased almost twofold after exposure of snail brains to the static magnetic field. Similarly, P-31 NMR data revealed a trend of increasing ATP consumption and increase in intracellular pH mediated by the Na+/H+ exchanger in snail brains exposed to the static magnetic field. Importantly, current clamp recordings from the Br neuron confirmed the increase in activity of the Na+/K+ pump after exposure to the static magnetic field, as the magnitude of ouabain's effect measured on the membrane resting potential, action potential, and interspike interval duration was higher in neurons exposed to the magnetic field. Metabolic pathways through which the magnetic field influenced the Na+/K+ pump could involve phosphorylation and dephosphorylation, as blocking these processes abolished the effect of the static magnetic field.",
publisher = "Springer, New York",
journal = "Journal of Comparative Physiology A-Neuroethology Sensory Neural and Behavioral Physiology",
title = "Involvement of Na+/K(+)pump in fine modulation of bursting activity of the snail Br neuron by 10 mT static magnetic field",
pages = "540-525",
number = "7",
volume = "198",
doi = "10.1007/s00359-012-0727-0"
}

Nikolić, L. M., Todorović, N., Zakrzewska, J., Stanić, M., Raus, S. Z., Kalauzi, A.,& Janac, B. B.. (2012). Involvement of Na+/K(+)pump in fine modulation of bursting activity of the snail Br neuron by 10 mT static magnetic field. in Journal of Comparative Physiology A-Neuroethology Sensory Neural and Behavioral Physiology
Springer, New York., 198(7), 525-540.
https://doi.org/10.1007/s00359-012-0727-0

Nikolić LM, Todorović N, Zakrzewska J, Stanić M, Raus SZ, Kalauzi A, Janac BB. Involvement of Na+/K(+)pump in fine modulation of bursting activity of the snail Br neuron by 10 mT static magnetic field. in Journal of Comparative Physiology A-Neuroethology Sensory Neural and Behavioral Physiology. 2012;198(7):525-540.
doi:10.1007/s00359-012-0727-0 .

Nikolić, Ljiljana M., Todorović, Nataša, Zakrzewska, Joanna, Stanić, Marina, Raus, Snežana Z, Kalauzi, Aleksandar, Janac, Branka B, "Involvement of Na+/K(+)pump in fine modulation of bursting activity of the snail Br neuron by 10 mT static magnetic field" in Journal of Comparative Physiology A-Neuroethology Sensory Neural and Behavioral Physiology, 198, no. 7 (2012):525-540,
https://doi.org/10.1007/s00359-012-0727-0 . .

TY  - JOUR
AU  - Spasić, Slađana
AU  - Nikolić, Ljiljana M.
AU  - Mutavdžić, Dragosav
AU  - Šaponjić, Jasna
PY  - 2011
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/468
AB  - We applied a combination of fractal analysis and Independent Component Analysis (ICA) method to detect the sources of fractal complexity in snail Br neuron activity induced by static magnetic field of 2.7 mT. The fractal complexity of Br neuron activity was analyzed before (Control), during (MF), and after (AMF) exposure to the static magnetic field in six experimental animals. We estimated the fractal dimension (FD) of electrophysiological signals using Higuchi's algorithm, and empirical FD distributions. By using the Principal Component Analysis (PCA) and FastICA algorithm we determined the number of components, and defined the statistically independent components (ICs) in the fractal complexity of signal waveforms. We have isolated two independent components of the empirical FD distributions for each of three groups of data by using FastICA algorithm. ICs represent the sources of fractal waveforms complexity of Br neuron activity in particular experimental conditions. Our main results have shown that there could be two opposite intrinsic mechanisms in single snail Br neuron response to static magnetic field stimulation. We named identified ICs that correspond to those mechanisms - the component of plasticity and the component of elasticity. We have shown that combination of fractal analysis with ICA method could be very useful for the decomposition and identification of the sources of fractal complexity of bursting neuronal activity waveforms.
PB  - Elsevier Ireland Ltd, Clare
T2  - Computer Methods and Programs in Biomedicine
T1  - Independent complexity patterns in single neuron activity induced by static magnetic field
EP  - 218
IS  - 2
SP  - 212
VL  - 104
DO  - 10.1016/j.cmpb.2011.07.006
ER  - 

@article{
author = "Spasić, Slađana and Nikolić, Ljiljana M. and Mutavdžić, Dragosav and Šaponjić, Jasna",
year = "2011",
abstract = "We applied a combination of fractal analysis and Independent Component Analysis (ICA) method to detect the sources of fractal complexity in snail Br neuron activity induced by static magnetic field of 2.7 mT. The fractal complexity of Br neuron activity was analyzed before (Control), during (MF), and after (AMF) exposure to the static magnetic field in six experimental animals. We estimated the fractal dimension (FD) of electrophysiological signals using Higuchi's algorithm, and empirical FD distributions. By using the Principal Component Analysis (PCA) and FastICA algorithm we determined the number of components, and defined the statistically independent components (ICs) in the fractal complexity of signal waveforms. We have isolated two independent components of the empirical FD distributions for each of three groups of data by using FastICA algorithm. ICs represent the sources of fractal waveforms complexity of Br neuron activity in particular experimental conditions. Our main results have shown that there could be two opposite intrinsic mechanisms in single snail Br neuron response to static magnetic field stimulation. We named identified ICs that correspond to those mechanisms - the component of plasticity and the component of elasticity. We have shown that combination of fractal analysis with ICA method could be very useful for the decomposition and identification of the sources of fractal complexity of bursting neuronal activity waveforms.",
publisher = "Elsevier Ireland Ltd, Clare",
journal = "Computer Methods and Programs in Biomedicine",
title = "Independent complexity patterns in single neuron activity induced by static magnetic field",
pages = "218-212",
number = "2",
volume = "104",
doi = "10.1016/j.cmpb.2011.07.006"
}

Spasić, S., Nikolić, L. M., Mutavdžić, D.,& Šaponjić, J.. (2011). Independent complexity patterns in single neuron activity induced by static magnetic field. in Computer Methods and Programs in Biomedicine
Elsevier Ireland Ltd, Clare., 104(2), 212-218.
https://doi.org/10.1016/j.cmpb.2011.07.006

Spasić S, Nikolić LM, Mutavdžić D, Šaponjić J. Independent complexity patterns in single neuron activity induced by static magnetic field. in Computer Methods and Programs in Biomedicine. 2011;104(2):212-218.
doi:10.1016/j.cmpb.2011.07.006 .

Spasić, Slađana, Nikolić, Ljiljana M., Mutavdžić, Dragosav, Šaponjić, Jasna, "Independent complexity patterns in single neuron activity induced by static magnetic field" in Computer Methods and Programs in Biomedicine, 104, no. 2 (2011):212-218,
https://doi.org/10.1016/j.cmpb.2011.07.006 . .

TY  - JOUR
AU  - Spasić, Slađana
AU  - Nikolić, Ljiljana M.
AU  - Mutavdžić, Dragosav
PY  - 2011
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/457
AB  - In the present work we report a new combination of fractal analysis and some advanced statistical methods and their application for the quantitative detection of the effects of a static magnetic field of 2.7 mT on fractal complexity changes of Br neuron activity in the subesophageal ganglia of the garden snail Helix pomatia. We used factor analysis (FA) in the analysis of the empirical distribution of fractal dimension (FD). FA showed that there are two factors in the empirical distribution of FD. Results indicated that the significant changes in the fractal complexity of Br neuron activity occurred during treatment with a magnetic field, were extended to the post exposure period.
PB  - Srpsko biološko društvo, Beograd, i dr.
T2  - Archives of Biological Sciences
T1  - Effect of a static magnetic field on the fractal complexity of bursting activity of the br neuron in the snail detected by factor analysis
EP  - 183
IS  - 1
SP  - 177
VL  - 63
DO  - 10.2298/ABS1101177S
ER  - 

@article{
author = "Spasić, Slađana and Nikolić, Ljiljana M. and Mutavdžić, Dragosav",
year = "2011",
abstract = "In the present work we report a new combination of fractal analysis and some advanced statistical methods and their application for the quantitative detection of the effects of a static magnetic field of 2.7 mT on fractal complexity changes of Br neuron activity in the subesophageal ganglia of the garden snail Helix pomatia. We used factor analysis (FA) in the analysis of the empirical distribution of fractal dimension (FD). FA showed that there are two factors in the empirical distribution of FD. Results indicated that the significant changes in the fractal complexity of Br neuron activity occurred during treatment with a magnetic field, were extended to the post exposure period.",
publisher = "Srpsko biološko društvo, Beograd, i dr.",
journal = "Archives of Biological Sciences",
title = "Effect of a static magnetic field on the fractal complexity of bursting activity of the br neuron in the snail detected by factor analysis",
pages = "183-177",
number = "1",
volume = "63",
doi = "10.2298/ABS1101177S"
}

Spasić, S., Nikolić, L. M.,& Mutavdžić, D.. (2011). Effect of a static magnetic field on the fractal complexity of bursting activity of the br neuron in the snail detected by factor analysis. in Archives of Biological Sciences
Srpsko biološko društvo, Beograd, i dr.., 63(1), 177-183.
https://doi.org/10.2298/ABS1101177S

Spasić S, Nikolić LM, Mutavdžić D. Effect of a static magnetic field on the fractal complexity of bursting activity of the br neuron in the snail detected by factor analysis. in Archives of Biological Sciences. 2011;63(1):177-183.
doi:10.2298/ABS1101177S .

Spasić, Slađana, Nikolić, Ljiljana M., Mutavdžić, Dragosav, "Effect of a static magnetic field on the fractal complexity of bursting activity of the br neuron in the snail detected by factor analysis" in Archives of Biological Sciences, 63, no. 1 (2011):177-183,
https://doi.org/10.2298/ABS1101177S . .