Maksim Patrushev

Mitochondrial permeability transition triggers the release of mtDNA fragments

Abstract.Fragments of mitochondrial DNA are released from mitochondria upon opening of the mitochondrial permeability transition pore. Cyclosporin A, an inhibitor of pore opening, completely prevented the release of mitochondrial fragments. Induction of mitochondrial permeability transition and subsequent release of the fragments of mitochondrial DNA could be one cause of genomic instability in the cell.

Silicon Dioxide Thin Film Mediated Single Cell Nucleic Acid Isolation

A limited amount of DNA extracted from single cells, and the development of single cell diagnostics make it necessary to create a new highly effective method for the single cells nucleic acids isolation. In this paper, we propose the DNA isolation method from biomaterials with limited DNA quantity in sample, and from samples with degradable DNA based on the use of solid-phase adsorbent silicon dioxide nanofilm deposited on the inner surface of PCR tube.

The nucleoid protein Dps binds genomic DNA of Escherichia coli in a non-random manner

Dps is a multifunctional homododecameric protein that oxidizes Fe2+ ions accumulating them in the form of Fe2O3 within its protein cavity, interacts with DNA tightly condensing bacterial nucleoid upon starvation and performs some other functions. During the last two decades from discovery of this protein, its ferroxidase activity became rather well studied, but the mechanism of Dps interaction with DNA still remains enigmatic. The crucial role of lysine residues in the unstructured N-terminal tails led to the conventional point of view that Dps binds DNA without sequence or structural specificity. However, deletion of dps changed the profile of proteins in starved cells, SELEX screen revealed genomic regions preferentially bound in vitro and certain affinity of Dps for artificial branched molecules was detected by atomic force microscopy. Here we report a non-random distribution of Dps binding sites across the bacterial chromosome in exponentially growing cells and show their enrichment with inverted repeats prone to form secondary structures. We found that the Dps-bound regions overlap with sites occupied by other nucleoid proteins, and contain overrepresented motifs typical for their consensus sequences. Of the two types of genomic domains with extensive protein occupancy, which can be highly expressed or transcriptionally silent only those that are enriched with RNA polymerase molecules were preferentially occupied by Dps. In the dps-null mutant we, therefore, observed a differentially altered expression of several targeted genes and found suppressed transcription from the dps promoter. In most cases this can be explained by the relieved interference with Dps for nucleoid proteins exploiting sequence-specific modes of DNA binding. Thus, protecting bacterial cells from different stresses during exponential growth, Dps can modulate transcriptional integrity of the bacterial chromosome hampering RNA biosynthesis from some genes via competition with RNA polymerase or, vice versa, competing with inhibitors to activate transcription.

Multifunctional Neurodevice for Recognition of Electrophysiological Signals and Data Transmission in an Exoskeleton Construction

The most important task of health care is the increasing of life expectancy and improving the quality of life of the population. Taking into consideration the high numbers of disability, it is very relevant to establish a high-precision neurodevice, allowing the integration of people with limited functional abilities into the society. This paper presents the provisional results of a research work, the main aim of which was to develop the multifunctional neurodevice with the ability to transfer data to an exoskeleton construction. In the first phase, we selected the optimal way for a neurodevice layout that would be capable to measure the electromyography (EMG), electroencephalography (EEG), electroocu- lography (EOG), photoplethysmography, body temperature for a long period of time, and also motor activity with the ability to send data to a remote practitioner in real time. The software was developed. Experiments were conducted; at the same time the final (residual) graphical results were compared with the commercially available devices. The experimental results showed a high accuracy of the signals of EEG, EMG, EOG, photoplethysmography, thermometry, and physical activity. In conclusion, with the participation of 10 healthy volunteers, the study of hybridization of EEG and EMG signals was carried out, and it showed a significant advantage in comparison with only one modal system. It is expected that a further work will allow us to formulate optimal technical solutions based on the present knowledge of human physiology. This would be the basis for creating a highly accurate and safe multifunction neurodevice and would be able to meet the medico-social needs and would help to reintegrate people with disabilities into society by connecting them to the robotic technique, to the exoskeletons.

Method of Photoplethysmography Diagnostics of Domesticated Animals Cardiovascular Diseases

At present time the standard procedure to diagnose cardiovascular diseases (CVD) of domesticated animals (dogs) is electrocardiography (ECG) monitoring at animal clinic. Sadly, results, obtained that way, are often mistaken because of stressful state of the animal, caused by medical manipulations [1]. The usage of photoplethysmography (PPG) method can become a good substitute for CVD monitoring. Main advantages of PPG, in compare with ECG, are single probe placement (on the ear or tailset), no need of gel electrodes and capability of measuring actual CVS parameters without need of special medical training or laboratory conditions. It is one of non-invasive methods for measuring the amount of the blood volume changes inside the blood vessels, applicable for cardio activity estimation by calculating heart rate variability. In most cases, PPG monitoring devises are small, easy to place and can monitor different physiological parameters of the animal, such as heart rate, pulse wave characteristics, blood oxygen saturation, etc.

The Particles Precipitation and Osseointegration of a Tio2 Thin-Film Coating by Ion Beam Deposition - An In vivo Study

Titanium-based materials are the most common materials implanted into the human body. Titanium and its alloys are widely applied as dental implants, bone fracture-fixation and artificial joints due to their good mechanical properties, favorable biocompatibility and excellent corrosion resistance [1,2]. The surface properties of Ti implants influence biological responses at the interface between bone tissue and implants and, consequently, their osseointegration [3,4]. Osseointegration is closely related to early interactions between the implant surface and its surrounding bone tissue. However, a surface modification of Ti is still required since spontaneously grown native TiO2 has no strong bioactivity to osseointegrate with bone [5]. Histological evaluation has shown that significantly more bone formation is found on nanoparticle-coated implants compared to non-treated titanium implants [6]. However, long-term maintenance of osseointegration and stability of titanium-based implants is still a problem [7]. Since the efficacy of osseointegration is influenced by factors including the surface condition of titanium implant, varied surface modifications have been performed to improve the osseointegration, such as inclusion of natural organic compounds, chemical treatments and controlled formation of TiO2 [8]. Beneficial modifications of titanium surfaces have been established, for example chemical etching of the surface in alkali solution or anodization at breakdown voltages (spark processing) [9-11]. For simple surface treatment of titanium, formation of TiO2nanostructure such as nanotube or with titanium oxide nanoparticle was studied [12]. TiO2 coatings with various deposition techniques, including electrophoretic deposition, radiofrequency sputtering, and pulsed laser deposition are investigated and developed [13,14]. But precise control over thickness, chemical composition, and stoichiometry during the growth of biocompatible nano coverings remains an issue. Additionally, various complications involving TiO2 coatings haven been reported by dentists. Specifically, fragility of the thin-film and poor bonding strength between the film and substrate material are serious problems that can result in cracking of the coated film and the film-substrate interface during dental implant operation [15].

Genetic Methods for Detecting Astrocytes, Neurons and Neurogenesis

Abstract Two sets of reactants for modelling neurogenesis (SRMN) were developed based on the designed and tested genetic structures of lentiviral vectors. SRMN-1 contains the genetic construct LVV-GFAP-GCaMP3 and is intended for cellspecific transduction in astroglia cells. SRMN-2 contains the genetic construct LVV-PRSx8-TN-XXL and is intended for the phenotype-specific transduction in neurons. The present study examined SRMN-1 and SRMN-2 samples and assessed their efficiency in vitro and in vivo in Norvegicus rats. Specificity to particular cell types for all SRMN samples exceeded 97%. The number of induced signalling cascades was determined via activation of intracellular ingsignalling cascades in neurons and astrocytes (purinergic receptors and β-adrenoceptors). The results demonstrated dynamic recording of fluorescent signals and a two-fold increase in intensity after addition of the activator in all samples. The experimental SRMN samples revealed successful and stable transfection of catecholaminergic neurons and astrocytes, data on transfection efficiency, specificity of the developed genetic structures of SRMN, and calcium dynamics in transfected neurons and astrocytes. These results confirm the crucial role of astrocytes in ensuring neurogenesis. The results in pure cell culture (in vitro) were identical to the in vivo results in animals.

Development of the Brain-computer Interface Based on the Biometric Control Channels and Multi-modal Feedback to Provide A Human with Neuro-electronic Systems and Exoskeleton Structures to Compensate the Motor Functions

The aim of this paper is to create a multi-functional neuro-device and to study the possibilities of long-term monitoring of several physiological parameters of an organism controlled by brain activity with transmitting the data to the exoskeleton. To achieve this goal, analytical review of modern scientific-and-technical, normative, technical, and medical literature involving scientific and technical problems has been performed; the research area has been chosen and justified, including the definition of optimal electrodes and their affixing to the body of the patient, the definition of the best suitable power source and its operation mode, the definition of the best suitable useful signal amplifiers, and a system of filtering off external noises. A neuro-device mock-up has been made for recognizing electrophysiological signals and transmitting them to the exoskeleton, also the software has been written. Investigation tests of the neuro-device mock-up have been performed, which showed the quality of electroencephalography, electromyography, electrooculography, photoplethysmography, and thermometry signals. The developed experimental model of the neuro-device will show all elaborated algorithms and hardware solutions in action to prove the claimed characteristics, which will allow to developing recommendations for using the neuro-device and a TDA to creata prototype of the brainmachine interface for controlling electromechanical devices.

Device for ambulatory diagnosis of pets cardiovascular system functional state.

This paper contains a description of device for ambulatory diagnosis of pet’s cardiovascular system functional state capable of measuring pulse wave parameters and storing obtained data. One of the main advantages of developed device practical application is elimination of animal anxiety caused by visit to veterinary clinic. The animal during the measurement does not experience any anxiety and stress. The dog’s cardiovascular system measurement result was obtained without the stress influence on the animals. This allows to significantly reducing measured pulse wave data misinterpretation. Easy handling of the device and capability of transferring data to external flash drives allows pet owner to make measurements domiciliary and pass the results to veterinarian during the next animal clinic visit.

Personalized monitoring of drug therapy effectiveness based on high-throughput analysis of drugs utilization and inflammatory factors closed functional networks in cardiovascular pathogenesis pathologies

Technical approaches 1. Remote real-time functional monitoring of patients; 2. Genome profiling (NGS); 3. Proteome profiling (IEF, LC MS/MS); 4. Cell function research (Flow cytometry, Live cell imaging); 5. Drugs and metabolites concentration control and association it with genomic constitution (LC MS/MS); 6. Quantification plasma concentration of the drugs and their metabolites, enzymes (LC MS/MS); 7. Immunologic profiling (ELISA, flow cytometry).