TY  - JOUR
AU  - Srdić-Rajić, Tatjana
AU  - Keković, Goran
AU  - Davidović, Dragomir M.
AU  - Metlaš, Radmila
PY  - 2013
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5519
AB  - A physical and mathematical model identifies similarities between phosphocholine-binding antibodies.A methodology based on the representation of each amino acid of a protein sequence by the electron-ion interaction potential and subsequent analysis by signal processing was used to determine the characteristic or common frequency (in Hz) that reflects the biological activity shared among phosphocholine (PC)-binding antibodies. The common frequency for the variable portion of the heavy chain (VH) of the PC-specific antibodies is found to be at f 0.37 Hz. The VH sequences of the PC-binding antibodies exhibit three subsites for the PC moiety where hypervariable region 2 (CDR2) plays a role in the interaction with the phosphate group. Mutations in this VH region have an impact on the ability of mutant variants to bind PC and its carrier molecule, as well as on the characteristic frequency shift toward f 0.12 Hz for mutants failing to bind both hapten and carrier. The VH sequence of mutants that retain the ability to bind PC still shows f 0.37 Hz, suggesting that this frequency determines PC binding. However, this statement was not confirmed as mutation in another PC subsite impairs PC binding but retains both the phosphate-group recognition and the frequency at f 0.37 Hz. Herein, this finding is discussed to promote the idea that the VH sequence of the PC-binding antibodies encodes the subsite for phosphate-group binding as a dominant functional activity and that only CDR2 of the T15-idiotype antibodies together with FR3 region form an autonomous self-association function represented by the T15VH5073 peptide with f 0.370.05 Hz. Thus, these data confirmed that T15VH50-73 peptide might be used in superantibody technology.
T2  - International Immunology
T1  - Phosphocholine-binding antibody activities are hierarchically encoded in the sequence of the heavy-chain variable region: dominance of self-association activity in the T15 idiotype
VL  - 25
IS  - 6
SP  - 345
EP  - 352
DO  - 10.1093/intimm/dxs156
ER  - 

@article{
author = "Srdić-Rajić, Tatjana and Keković, Goran and Davidović, Dragomir M. and Metlaš, Radmila",
year = "2013",
abstract = "A physical and mathematical model identifies similarities between phosphocholine-binding antibodies.A methodology based on the representation of each amino acid of a protein sequence by the electron-ion interaction potential and subsequent analysis by signal processing was used to determine the characteristic or common frequency (in Hz) that reflects the biological activity shared among phosphocholine (PC)-binding antibodies. The common frequency for the variable portion of the heavy chain (VH) of the PC-specific antibodies is found to be at f 0.37 Hz. The VH sequences of the PC-binding antibodies exhibit three subsites for the PC moiety where hypervariable region 2 (CDR2) plays a role in the interaction with the phosphate group. Mutations in this VH region have an impact on the ability of mutant variants to bind PC and its carrier molecule, as well as on the characteristic frequency shift toward f 0.12 Hz for mutants failing to bind both hapten and carrier. The VH sequence of mutants that retain the ability to bind PC still shows f 0.37 Hz, suggesting that this frequency determines PC binding. However, this statement was not confirmed as mutation in another PC subsite impairs PC binding but retains both the phosphate-group recognition and the frequency at f 0.37 Hz. Herein, this finding is discussed to promote the idea that the VH sequence of the PC-binding antibodies encodes the subsite for phosphate-group binding as a dominant functional activity and that only CDR2 of the T15-idiotype antibodies together with FR3 region form an autonomous self-association function represented by the T15VH5073 peptide with f 0.370.05 Hz. Thus, these data confirmed that T15VH50-73 peptide might be used in superantibody technology.",
journal = "International Immunology",
title = "Phosphocholine-binding antibody activities are hierarchically encoded in the sequence of the heavy-chain variable region: dominance of self-association activity in the T15 idiotype",
volume = "25",
number = "6",
pages = "345-352",
doi = "10.1093/intimm/dxs156"
}

Srdić-Rajić, T., Keković, G., Davidović, D. M.,& Metlaš, R.. (2013). Phosphocholine-binding antibody activities are hierarchically encoded in the sequence of the heavy-chain variable region: dominance of self-association activity in the T15 idiotype. in International Immunology, 25(6), 345-352.
https://doi.org/10.1093/intimm/dxs156

Srdić-Rajić T, Keković G, Davidović DM, Metlaš R. Phosphocholine-binding antibody activities are hierarchically encoded in the sequence of the heavy-chain variable region: dominance of self-association activity in the T15 idiotype. in International Immunology. 2013;25(6):345-352.
doi:10.1093/intimm/dxs156 .

Srdić-Rajić, Tatjana, Keković, Goran, Davidović, Dragomir M., Metlaš, Radmila, "Phosphocholine-binding antibody activities are hierarchically encoded in the sequence of the heavy-chain variable region: dominance of self-association activity in the T15 idiotype" in International Immunology, 25, no. 6 (2013):345-352,
https://doi.org/10.1093/intimm/dxs156 . .

TY  - JOUR
AU  - Keković, Goran
AU  - Milovanović, Branislav
AU  - Davidović, Dragomir
AU  - Raković, Dejan
AU  - Culic, Milka
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5428
AB  - Objective: We investigated the effects of bisoprolol and losartan on subjects with essential hypertension, by conducting heart rate variability (HRV) analysis of ECG signals. Our intention was to establish the set of linear and nonlinear heart rate variability parameters, which could be used as a noninvasive markers in the treatment of hypertension. Materials and Methods: Sixty subjects with essential hypertension included in this study were divided in two groups. During the four weeks medical treatment, the first group was administered with daily oral dose of 5 mg of bisoprolol and the second with daily oral dose of 50 mg of losartan. We recorded ECG signals, and performed HRV analysis of consecutive RR time intervals, before and after a month of pharmacological therapy. Results: In the case of bisoprolol, statistically the most significant changes of HRV parameters were: TP (1814.1 +/- 1731.3 ms(2) vs. 761.3 +/- 725.0 ms(2), P LT 0.0001), RR (870.2 +/- 105.7 ms vs. 1027.2 +/- 150.0 ms, P LT 0.0001), HR (70.81 +/- 8.42 bp/min vs. 60.10 +/- 9.52 bp/min, P LT 0.0001). In the case of losartan, the most significant changes were: SDNN (43.16 +/- 17.27 ms vs. 237.98 +/- 118.54 ms, P = 0.002), rmSDD (27.09 +/- 18.27 ms vs. 46.82 +/- 37.71 ms, P = 0.003), SD2 (55.18 +/- 20.6 vs. 70.67 +/- 26.12, P LT 0.019) and DF2 (0.69 +/- 0.21 vs. 0.86 +/- 0.25, P LT 0.014). Conclusion: Effects of bisoprolol and losartan were especially manifested among the set of linear HRV parameters. As a consequence of effect of losartan, we singled out the nonlinear parameters SD2 and DF2.
T2  - Journal of Research in Medical Sciences
T1  - Comparative effect of bisoprolol and losartan in the treatment of essential hypertension
VL  - 17
IS  - 11
SP  - 1027
EP  - 1032
UR  - https://hdl.handle.net/21.15107/rcub_vinar_5428
ER  - 

@article{
author = "Keković, Goran and Milovanović, Branislav and Davidović, Dragomir and Raković, Dejan and Culic, Milka",
year = "2012",
abstract = "Objective: We investigated the effects of bisoprolol and losartan on subjects with essential hypertension, by conducting heart rate variability (HRV) analysis of ECG signals. Our intention was to establish the set of linear and nonlinear heart rate variability parameters, which could be used as a noninvasive markers in the treatment of hypertension. Materials and Methods: Sixty subjects with essential hypertension included in this study were divided in two groups. During the four weeks medical treatment, the first group was administered with daily oral dose of 5 mg of bisoprolol and the second with daily oral dose of 50 mg of losartan. We recorded ECG signals, and performed HRV analysis of consecutive RR time intervals, before and after a month of pharmacological therapy. Results: In the case of bisoprolol, statistically the most significant changes of HRV parameters were: TP (1814.1 +/- 1731.3 ms(2) vs. 761.3 +/- 725.0 ms(2), P LT 0.0001), RR (870.2 +/- 105.7 ms vs. 1027.2 +/- 150.0 ms, P LT 0.0001), HR (70.81 +/- 8.42 bp/min vs. 60.10 +/- 9.52 bp/min, P LT 0.0001). In the case of losartan, the most significant changes were: SDNN (43.16 +/- 17.27 ms vs. 237.98 +/- 118.54 ms, P = 0.002), rmSDD (27.09 +/- 18.27 ms vs. 46.82 +/- 37.71 ms, P = 0.003), SD2 (55.18 +/- 20.6 vs. 70.67 +/- 26.12, P LT 0.019) and DF2 (0.69 +/- 0.21 vs. 0.86 +/- 0.25, P LT 0.014). Conclusion: Effects of bisoprolol and losartan were especially manifested among the set of linear HRV parameters. As a consequence of effect of losartan, we singled out the nonlinear parameters SD2 and DF2.",
journal = "Journal of Research in Medical Sciences",
title = "Comparative effect of bisoprolol and losartan in the treatment of essential hypertension",
volume = "17",
number = "11",
pages = "1027-1032",
url = "https://hdl.handle.net/21.15107/rcub_vinar_5428"
}

Keković, G., Milovanović, B., Davidović, D., Raković, D.,& Culic, M.. (2012). Comparative effect of bisoprolol and losartan in the treatment of essential hypertension. in Journal of Research in Medical Sciences, 17(11), 1027-1032.
https://hdl.handle.net/21.15107/rcub_vinar_5428

Keković G, Milovanović B, Davidović D, Raković D, Culic M. Comparative effect of bisoprolol and losartan in the treatment of essential hypertension. in Journal of Research in Medical Sciences. 2012;17(11):1027-1032.
https://hdl.handle.net/21.15107/rcub_vinar_5428 .

Keković, Goran, Milovanović, Branislav, Davidović, Dragomir, Raković, Dejan, Culic, Milka, "Comparative effect of bisoprolol and losartan in the treatment of essential hypertension" in Journal of Research in Medical Sciences, 17, no. 11 (2012):1027-1032,
https://hdl.handle.net/21.15107/rcub_vinar_5428 .

TY  - JOUR
AU  - Keković, Goran
AU  - Raković, Dejan
AU  - Tosic, B.
AU  - Davidović, David
AU  - Cosic, I.
PY  - 2010
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6869
AB  - Biomolecular recognition is an open scientific problem, which has been investigated in many theoretical and experimental aspects. In that sense, there are encouraging results within Resonant Recognition Model (RRM), based on the finding that there is a significant correlation between spectra of the numerical presentation of amino acids in the primary structure of proteins and their biological activity. It has been found through an extensive research that proteins with the same biological function have a common frequency in their numerical spectra. This frequency was found then to be a characteristic feature for protein biological function or interaction The RRM model proposes that the selectivity of protein interactions is based on resonant energy transfer between interacting biomolecules and that this energy, electromagnetic in its nature, is in the frequency range of 10(13) to 10(15) Hz, which incorporates infra-red (IR), visible and a small portion of the ultra-violet (UV) radiation. In this paper, the quantum mechanical basis of the RRM model will be investigated using the solution in the simplified framework of Huckel-like theory of molecular orbits.
T2  - Acta Physica Polonica A
T1  - Quantum Foundations of Resonant Recognition Model
VL  - 117
IS  - 5
SP  - 756
EP  - 759
DO  - 10.12693/APhysPolA.117.756
ER  - 

@article{
author = "Keković, Goran and Raković, Dejan and Tosic, B. and Davidović, David and Cosic, I.",
year = "2010",
abstract = "Biomolecular recognition is an open scientific problem, which has been investigated in many theoretical and experimental aspects. In that sense, there are encouraging results within Resonant Recognition Model (RRM), based on the finding that there is a significant correlation between spectra of the numerical presentation of amino acids in the primary structure of proteins and their biological activity. It has been found through an extensive research that proteins with the same biological function have a common frequency in their numerical spectra. This frequency was found then to be a characteristic feature for protein biological function or interaction The RRM model proposes that the selectivity of protein interactions is based on resonant energy transfer between interacting biomolecules and that this energy, electromagnetic in its nature, is in the frequency range of 10(13) to 10(15) Hz, which incorporates infra-red (IR), visible and a small portion of the ultra-violet (UV) radiation. In this paper, the quantum mechanical basis of the RRM model will be investigated using the solution in the simplified framework of Huckel-like theory of molecular orbits.",
journal = "Acta Physica Polonica A",
title = "Quantum Foundations of Resonant Recognition Model",
volume = "117",
number = "5",
pages = "756-759",
doi = "10.12693/APhysPolA.117.756"
}

Keković, G., Raković, D., Tosic, B., Davidović, D.,& Cosic, I.. (2010). Quantum Foundations of Resonant Recognition Model. in Acta Physica Polonica A, 117(5), 756-759.
https://doi.org/10.12693/APhysPolA.117.756

Keković G, Raković D, Tosic B, Davidović D, Cosic I. Quantum Foundations of Resonant Recognition Model. in Acta Physica Polonica A. 2010;117(5):756-759.
doi:10.12693/APhysPolA.117.756 .

Keković, Goran, Raković, Dejan, Tosic, B., Davidović, David, Cosic, I., "Quantum Foundations of Resonant Recognition Model" in Acta Physica Polonica A, 117, no. 5 (2010):756-759,
https://doi.org/10.12693/APhysPolA.117.756 . .

TY  - JOUR
AU  - Keković, Goran
AU  - Raković, Dejan
AU  - Davidović, Dragomir M.
PY  - 2009
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6796
AB  - A theoretical model for calculation of equilibrium concentrations of isomeric butane molecule forms, and also the forms of hydrocarbons of the alkene series, is proposed. We considered the changes of internal rotational potential energy in respect of reaction coordinate, of rapid conversion of butane isomers from one form to another at room temperature. This is very important for better understanding of the nature of chemical reactions in butane, because the changes of internal rotational potential energy reflect conformational transitions of butane and changes of its chemical and physical properties. The presented model is based on Gribovs system of kinetic equations for isomer-isomer transitions. The canonical ensemble is used to calculate the room temperature probabilities of the rotoisomer conformational states as functions of dihedrial angle. and the obtained results are in good agreement with available ones. Also, in a sense of calculated lifetime of unstable rotoisomers ( LT 10(-10) s) our results are comparable with coupled cluster and density functional calculations on alkene derivatives.
T2  - Acta Physica Polonica A
T1  - Kinetics of Non-Radiative Rotational Isomer Butane Transitions
VL  - 115
IS  - 4
SP  - 775
EP  - 777
DO  - 10.12693/APhysPolA.115.775
ER  - 

@article{
author = "Keković, Goran and Raković, Dejan and Davidović, Dragomir M.",
year = "2009",
abstract = "A theoretical model for calculation of equilibrium concentrations of isomeric butane molecule forms, and also the forms of hydrocarbons of the alkene series, is proposed. We considered the changes of internal rotational potential energy in respect of reaction coordinate, of rapid conversion of butane isomers from one form to another at room temperature. This is very important for better understanding of the nature of chemical reactions in butane, because the changes of internal rotational potential energy reflect conformational transitions of butane and changes of its chemical and physical properties. The presented model is based on Gribovs system of kinetic equations for isomer-isomer transitions. The canonical ensemble is used to calculate the room temperature probabilities of the rotoisomer conformational states as functions of dihedrial angle. and the obtained results are in good agreement with available ones. Also, in a sense of calculated lifetime of unstable rotoisomers ( LT 10(-10) s) our results are comparable with coupled cluster and density functional calculations on alkene derivatives.",
journal = "Acta Physica Polonica A",
title = "Kinetics of Non-Radiative Rotational Isomer Butane Transitions",
volume = "115",
number = "4",
pages = "775-777",
doi = "10.12693/APhysPolA.115.775"
}

Keković, G., Raković, D.,& Davidović, D. M.. (2009). Kinetics of Non-Radiative Rotational Isomer Butane Transitions. in Acta Physica Polonica A, 115(4), 775-777.
https://doi.org/10.12693/APhysPolA.115.775

Keković G, Raković D, Davidović DM. Kinetics of Non-Radiative Rotational Isomer Butane Transitions. in Acta Physica Polonica A. 2009;115(4):775-777.
doi:10.12693/APhysPolA.115.775 .

Keković, Goran, Raković, Dejan, Davidović, Dragomir M., "Kinetics of Non-Radiative Rotational Isomer Butane Transitions" in Acta Physica Polonica A, 115, no. 4 (2009):775-777,
https://doi.org/10.12693/APhysPolA.115.775 . .

TY  - JOUR
AU  - Raković, Dejan
AU  - Dugic, M.
AU  - Plavsic, M.
AU  - Keković, Goran
AU  - Cosic, I.
AU  - Davidovic, D.
PY  - 2006
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6616
AB  - Our recently proposed quantum approach to biomolecular recognition processes is hereby additionally supported by biomolecular Resonant Recognition Model and by quantum-chemical theory of biomolecular non-radiative resonant transitions. Previously developed general quantum-decoherence framework for biopolymer conformational changes in very selective ligand-proteins/target-receptors key/lock biomolecular recognition processes (with electron-conformational coupling, giving rise to dynamical modification of many-electron energy-state hypersurface of the cellular quantum-ensemble ligand-proteins/target-receptors biomolecular macroscopic quantum system, with revealed possibility to consider cellular biomolecular recognition as a Hopfield-like quantum-holographic associative neural network) is further extended from nonlocal macroscopic-quantum level of biological cell to nonlocal macroscopic-quantum level of biological organism, based on long-range coherent microwave excitations (as supported by macroscopic quantum-like microwave resonance therapy of the acupuncture system) - which might be of fundamental importance in understanding of underlying macroscopic quantum (quantum-holographic Hopfield-like) control mechanisms of embryogenesis/ontogenesis and morphogenesis, and their backward influence on the expression of genes.
T2  - Materials Science Forum
T1  - Quantum decoherence and quantum-holographic information processes: From biomolecules to biosystems
VL  - 518
SP  - 485
EP  - 490
DO  - 10.4028/www.scientific.net/MSF.518.485
ER  - 

@article{
author = "Raković, Dejan and Dugic, M. and Plavsic, M. and Keković, Goran and Cosic, I. and Davidovic, D.",
year = "2006",
abstract = "Our recently proposed quantum approach to biomolecular recognition processes is hereby additionally supported by biomolecular Resonant Recognition Model and by quantum-chemical theory of biomolecular non-radiative resonant transitions. Previously developed general quantum-decoherence framework for biopolymer conformational changes in very selective ligand-proteins/target-receptors key/lock biomolecular recognition processes (with electron-conformational coupling, giving rise to dynamical modification of many-electron energy-state hypersurface of the cellular quantum-ensemble ligand-proteins/target-receptors biomolecular macroscopic quantum system, with revealed possibility to consider cellular biomolecular recognition as a Hopfield-like quantum-holographic associative neural network) is further extended from nonlocal macroscopic-quantum level of biological cell to nonlocal macroscopic-quantum level of biological organism, based on long-range coherent microwave excitations (as supported by macroscopic quantum-like microwave resonance therapy of the acupuncture system) - which might be of fundamental importance in understanding of underlying macroscopic quantum (quantum-holographic Hopfield-like) control mechanisms of embryogenesis/ontogenesis and morphogenesis, and their backward influence on the expression of genes.",
journal = "Materials Science Forum",
title = "Quantum decoherence and quantum-holographic information processes: From biomolecules to biosystems",
volume = "518",
pages = "485-490",
doi = "10.4028/www.scientific.net/MSF.518.485"
}

Raković, D., Dugic, M., Plavsic, M., Keković, G., Cosic, I.,& Davidovic, D.. (2006). Quantum decoherence and quantum-holographic information processes: From biomolecules to biosystems. in Materials Science Forum, 518, 485-490.
https://doi.org/10.4028/www.scientific.net/MSF.518.485

Raković D, Dugic M, Plavsic M, Keković G, Cosic I, Davidovic D. Quantum decoherence and quantum-holographic information processes: From biomolecules to biosystems. in Materials Science Forum. 2006;518:485-490.
doi:10.4028/www.scientific.net/MSF.518.485 .

Raković, Dejan, Dugic, M., Plavsic, M., Keković, Goran, Cosic, I., Davidovic, D., "Quantum decoherence and quantum-holographic information processes: From biomolecules to biosystems" in Materials Science Forum, 518 (2006):485-490,
https://doi.org/10.4028/www.scientific.net/MSF.518.485 . .

TY  - JOUR
AU  - Keković, Goran
AU  - Ivić, Zoran
AU  - Kostić, Dragan
PY  - 1998
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2109
AB  - The possible large-polaron contribution to the neutron scattering on quasi-one-dimensional molecular crystals was examined within the continuum polaron model. It was found that the appearance of the central peak in the dynamic structure factor should be expected if large-polaron formation takes place. The possibility of the experimental verification of the existence of Davydov-like solitons in biological systems was discussed on the basis of these predictions.
T2  - Europhysics Letters / EPL
T1  - On the neutron scattering on large polarons in quasi-one-dimensional molecular crystals
VL  - 41
IS  - 3
SP  - 285
EP  - 290
DO  - 10.1209/epl/i1998-00144-3
ER  - 

@article{
author = "Keković, Goran and Ivić, Zoran and Kostić, Dragan",
year = "1998",
abstract = "The possible large-polaron contribution to the neutron scattering on quasi-one-dimensional molecular crystals was examined within the continuum polaron model. It was found that the appearance of the central peak in the dynamic structure factor should be expected if large-polaron formation takes place. The possibility of the experimental verification of the existence of Davydov-like solitons in biological systems was discussed on the basis of these predictions.",
journal = "Europhysics Letters / EPL",
title = "On the neutron scattering on large polarons in quasi-one-dimensional molecular crystals",
volume = "41",
number = "3",
pages = "285-290",
doi = "10.1209/epl/i1998-00144-3"
}

Keković, G., Ivić, Z.,& Kostić, D.. (1998). On the neutron scattering on large polarons in quasi-one-dimensional molecular crystals. in Europhysics Letters / EPL, 41(3), 285-290.
https://doi.org/10.1209/epl/i1998-00144-3

Keković G, Ivić Z, Kostić D. On the neutron scattering on large polarons in quasi-one-dimensional molecular crystals. in Europhysics Letters / EPL. 1998;41(3):285-290.
doi:10.1209/epl/i1998-00144-3 .

Keković, Goran, Ivić, Zoran, Kostić, Dragan, "On the neutron scattering on large polarons in quasi-one-dimensional molecular crystals" in Europhysics Letters / EPL, 41, no. 3 (1998):285-290,
https://doi.org/10.1209/epl/i1998-00144-3 . .