![]() Ignatenko, Andrew ![]() Doctoral thesis (2016) In the current thesis the model of the ROS management network is built using the domino principle. The model offers insight into the design principles underlying the ROS management network and enlightens ... [more ▼] In the current thesis the model of the ROS management network is built using the domino principle. The model offers insight into the design principles underlying the ROS management network and enlightens its functionality in the diseases such as cancer and Parkinson’s disease (PD). It is validated using experimental data. The model is used for in silico study of the ROS management dynamics under the stress conditions (oxidative stress). This highlights the phenomena of both adaptation to stress and the stress accumulation effect in case of repeated stress. This study also helps to discover the potential ways to a personalized treatment of the insufficient ROS management. The different ways of a control of the ROS management network are shown using the optimal control approach. Obtained results could be used for a seeking of the treatment strategies to fix the ROS management failures caused by an oxidative stress, neurodegenerative diseases, etc. Or, in vice versa, to develop the ways of a controllable cell death that might be used in cancer research. [less ▲] Detailed reference viewed: 119 (13 UL)![]() Ignatenko, Andrew ![]() Presentation (2015, January 23) Detailed reference viewed: 71 (1 UL)![]() Kolodkin, Alexey ![]() ![]() Poster (2014, December) Detailed reference viewed: 180 (14 UL)![]() Ignatenko, Andrew ![]() Presentation (2014, November 06) Detailed reference viewed: 68 (3 UL)![]() Kolodkin, Alexey ![]() ![]() Poster (2014, October) Detailed reference viewed: 181 (17 UL)![]() Kolodkin, Alexey ![]() ![]() ![]() Poster (2014, September) Detailed reference viewed: 177 (7 UL)![]() Kolodkin, Alexey ![]() ![]() Poster (2014, June) Detailed reference viewed: 185 (11 UL)![]() Ignatenko, Andrew ![]() ![]() ![]() in Proceedings of ICCSA 2014 (2014, June) Reactive oxygen species (ROS) play important role in the functioning of any cell and especially in the lifecycle of mitochondria. Since the action of ROS can be both positive and negative then the ... [more ▼] Reactive oxygen species (ROS) play important role in the functioning of any cell and especially in the lifecycle of mitochondria. Since the action of ROS can be both positive and negative then the remarkable role can be played by ROS regulation system. We constructed three different ODE based kinetic models of different complexity for the ROS management system and shown the difference in the dynamics of these systems under different conditions. Using results of numerical simulation we showed that extraction of some subsystems can make the model more unstable. We also introduced the objective function for comparison of the models with structure of different complexity [less ▲] Detailed reference viewed: 209 (35 UL)![]() Kolodkin, Alexey ![]() ![]() Poster (2014, June) Detailed reference viewed: 164 (16 UL)![]() Ignatenko, Andrew ![]() Presentation (2013, October 24) Detailed reference viewed: 53 (2 UL)![]() Kolodkin, Alexey ![]() ![]() Poster (2013, September 27) In vivo evidence demonstrates three fundamental interconnected adaptive survival mechanisms , which protect against excessive ROS that is generated during mitochondrial dysfunction: (i) autophagy ... [more ▼] In vivo evidence demonstrates three fundamental interconnected adaptive survival mechanisms , which protect against excessive ROS that is generated during mitochondrial dysfunction: (i) autophagy/mitophagy, (ii) adaptive antioxidant response and (iii) NFkB signaling in cancer and neurodegeneration. We have been expanding a kinetic model which recapitulates the consensus understanding of the mechanisms responsible for cellular ROS – management system and performed modular analysis to analyze emergent behavior. We started with the simplest model and added stepwise new modules. We identify the qualitative role (certain emergent behavior) attributed to each module and thus understand the design principles of the system. We propose a detailed, mechanistic, kinetic model for studying how mutations relevant for diseases such as PD and cancer affect the emergent behavior of ROS management network. [less ▲] Detailed reference viewed: 316 (11 UL)![]() ![]() Simeonidis, Vangelis ![]() ![]() ![]() Poster (2013, July 22) Reactive Oxygen Species (ROS) generation is an unavoidable background process during normal cellular function. The main contributor to ROS production is the electron transport chain, which reduces oxygen ... [more ▼] Reactive Oxygen Species (ROS) generation is an unavoidable background process during normal cellular function. The main contributor to ROS production is the electron transport chain, which reduces oxygen to water. Some incompletely-reduced oxygen species escape and oxidize a variety of organic molecules, leading to molecular dysfunction and initiating a positive feedback loop of ever increasing active radical production. The increased concentration of ROS damages the mitochondria, therefore further elevating the rate of ROS generation. Healthy cells manage ROS enzymatically and by mitophagy of damaged mitochondria. The precise tuning of the latter mechanism is crucial for cell survival and is controlled by a ROS-induced regulatory network. We have built a set of kinetic models of varying complexity, based on the current understanding of the mechanism of cellular ROS defense. Our models allow simulation of various patho-physiological scenarios related to mitochondrial dysfunction and the failure of the system of ROS regulation in human cells. We employ the models we have constructed to simulate the effects of diseases related to mitochondrial dysfunction and excessive ROS generation, such as Parkinson’s disease, Huntington’s disease and cancer. Experimental evidence is used for model fitting, and we propose model improvements based on incorporation of single-cell experimental measurements. Finally, we discuss the perspective of integrating our kinetic models with genome-scale, constraint-based, tissue-specific models of metabolism, in order to study the effect of ROS misregulation on metabolic phenotype. [less ▲] Detailed reference viewed: 175 (5 UL)![]() Kolodkin, Alexey ![]() ![]() ![]() Poster (2013, May) Reactive Oxygen Species (ROS) generation is an unavoidable background process in the normal functioning of the cell. The greatest contributor to ROS production is the electron transport chain (ETC) where ... [more ▼] Reactive Oxygen Species (ROS) generation is an unavoidable background process in the normal functioning of the cell. The greatest contributor to ROS production is the electron transport chain (ETC) where O2 is reduced to H2O. Some incompletely-reduced oxygen species escape and oxidize a variety of organic molecules (e.g. proteins and lipids in the mitochondrial membrane), leading to molecular dysfunction and initiating a positive feedback loop leading to generation of even more active radicals. Increased ROS concentration damages mitochondria and further increases ROS generation. Healthy cells manage ROS enzymatically with superoxide dismutase and other enzymes, various antioxidants, and ultimately through increased mitophagy of damaged mitochondria. The precise tuning of the latter mechanism is crucial for cell survival and is controlled in the cell by a ROS-induced regulatory network, which consists of many components such as Nrf2, Keap1, Parkin and p62 with a rather complicated cross-talk (Figure 1). In many diseases (cancer, Parkinson’s disease (PD), Huntington’s disease (HD), etc.), various components of the ROS management network are altered. Deconstructing the molecular mechanisms underlying or resulting from these alterations might contribute to better understanding of the dynamics of related pathophysiological processes. We have built a kinetics-based model which recapitulates the consensus understanding of the mechanism responsible for cellular ROS – managing system. [less ▲] Detailed reference viewed: 240 (10 UL)![]() Ignatenko, Andrew ![]() in New Journal of Physics (2013), 15 We propose a scheme for the reconstruction of the quantum state without a priori knowledge about the measurement setup. Using the data pattern approach, we develop an iterative procedure for obtaining ... [more ▼] We propose a scheme for the reconstruction of the quantum state without a priori knowledge about the measurement setup. Using the data pattern approach, we develop an iterative procedure for obtaining information about the measurement which is sufficient for an estimation of a particular signal state. The method is illustrated with the examples of reconstruction with on/off detection and quantum homodyne tomography. [less ▲] Detailed reference viewed: 130 (6 UL)![]() ; ; Ignatenko, Andrew ![]() in Optics and Spectroscopy (2010), 108(3), 425-432 The possibility of using the long-lived entangled state between the emitter and field near the band edge of the density of states of a photonic crystal to create an efficient generator of single photons ... [more ▼] The possibility of using the long-lived entangled state between the emitter and field near the band edge of the density of states of a photonic crystal to create an efficient generator of single photons is considered. The generator can be efficiently excited by incoherent pumping, excludes simultaneous generation of two photons, and ensures a high probability of extracting the photon into a specified mode. [less ▲] Detailed reference viewed: 129 (1 UL)![]() Ignatenko, Andrew ![]() in Optics and Spectroscopy (2010), 108(3), 412-416 The dynamics of the elementary photoelectric conversion in the interaction of a single-mode electromagnetic field with an arbitrary photon number distribution and a bound electron in a 1D rectangular ... [more ▼] The dynamics of the elementary photoelectric conversion in the interaction of a single-mode electromagnetic field with an arbitrary photon number distribution and a bound electron in a 1D rectangular potential well is considered. It is shown that if the frequency of the coherent field exceeds the frequency corresponding to the electron work function, the photoexcitation of this electron is incomplete. [less ▲] Detailed reference viewed: 120 (1 UL)![]() Ignatenko, Andrew ![]() in Optics and Spectroscopy (2007), 103(1), 121-128 Dynamics of the elementary photoelectric conversion upon interaction of a single-photon mode with a bound electron in a one-dimensional rectangular potential well is considered. The spatial and temporal ... [more ▼] Dynamics of the elementary photoelectric conversion upon interaction of a single-photon mode with a bound electron in a one-dimensional rectangular potential well is considered. The spatial and temporal dynamics of the wave packet corresponding to a free photoelectron is investigated. [less ▲] Detailed reference viewed: 122 (1 UL) |
||