Comparison of machine learning methods for analysis of ulcerative colitis proteomic data

Ulcerative colitis is a chronic inflammatory disease of the gastrointestinal system, affecting adults and children. Its cause is unknown, and the knowledge of reliable biomarkers is limited, especially for children. That makes the search for new biomarkers and pushing forth the analysis of the available data particularly challenging. We investigate proteomic data from children patients as a promising source, and tackle the problem implementing the recently developed parenclitic network approach to machine learning algorithms that solve classification task for proteomic data from healthy and diseased. We expect our approach to be applicable to other gastrointestinal diseases

Comparative analysis of results of treatment patients with severe spinal deformities using screw and a hybrid hardware

Purpose: evaluation of efficacy of operative treatment with the use of screw and hybrid metal constructions in idiopathic scoliosis associated with severe spine deformities. Material and methods: The outcomes of treatment of 34 patients aged 15 to 27 years old with severe scoliosisoperated on using screw metal constructions, were reviewed. 22 patients operated on with the use of hybrid metal constructions, made a control group. The groups were compared by the following parameters: pre- and postoperative Cobb angle, deformity mobility according to traction test, total sagittal/frontal balance, CT apical vertebra rotation, operation time, intraoperative blood loss, the number of instrumented vertebrae, and correction failure at 24-hr spondylograms. Results: Group A (screw spine fixation) demonstrated better outcomes compared to group B (combined spine fixation) in the following parameters. Postoperative correction was 48% and 41%;apical vertebra rotation decreased from 78° to 55° (30%) and from 74° to 59°(21%);total sagittal/frontal balance decreased from 39/25 mmto 14/12 mm (64/52%) and from 35/26 mm to 16/15 mm (55/43%), correspondingly. These results suggest better trunk compensation and postoperative correction in a group of patients with screw fixation. Smaller values of correction failure of the main arc as well as insignificant increase of thoracic kyphosis in the postoperative period (24 months) 3.8%/4.3% in group A compared to 6.2%/7.5% in group B testify to greater reliability and stability of ‘all screw’ metal constructions. The number of fixed elements was on average one more in a group with combined fixation (13 and 14, correspondingly)

OPERATIVE TREATMENT OF SPINAL DEFORMITIES IN PATIENTS WITH CEREBRAL PALSY

Surgical treatment of scoliosis on the background of cerebral palsy is carried out by the correction and polysegmental fixation of the spine and helps to improve balance the body, activate patient in a wheelchair, to prevent the subsequent progression of spinal deformity and rib cage, and improve self-care patients

COMPARATIVE ANALYSIS OF RADIOLOGIC ASPECTS OF FACET JOINTS IN SURGICAL TREATMENT OF PATIENTS WITH DEGENERATIVE DISEASES OF THE LUMBAR SPINE

Objective To study the radiologic characteristics of facet joints at different stages of the degenerative process in the lumbar spine to determine the indications for various methods of fixing the affected segment and to evaluate the results of treatment.Material and Methods To determine the radiologic aspects of facet joints in the affected area and in  adjacent segments of the lumbar spine, two groups were formed, including 136 patients who underwent multispiral computed tomography in two-energy mode before surgery and 12 months after surgery. Group I included patients who underwent rigid fixation of the spine (360°), and group II included patients who underwent dynamic fixation using nitinol rods (180°).Results Based on a comprehensive instrumental study, it was found that the degeneration of the intervertebral disc according to Pfirrmann II and III revealed an increase in the density of the cartilaginous plate in facet joints (HU). These digital indicators confirm the preservation of joint functionality, both in the affected area and in adjacent segments. With severe degrees of disk degeneration in Pfirrmann IV and V and facet joints, deep pathological changes occurred, directed towards the loss of facet joints functionality.Conclusion The obtained digital indicators of dual-energy computed tomography for the state of facet joints  in combination with the results of magnetic resonance imaging can be used as criteria in a complex of patient studies to assess the degree of degeneration of the vertebral motion segment in the affected area and adjacent segments. We recommend using these criteria as a diagnostic component for finding optimal methods of surgical treatment

Gluthatione system during physical loads and alimentary factor impact on it

Objective: to evaluate the functioning of gluthatione system (GS) in organism of swimmers during considerable endurance physical loads and to reveal the influence of nutritional factors on these features. Materials and methods: two groups of swimmers were studied. Sportsmen of the first group consumed «Sport nutrition product» (SNP) based on vegetable raw materials, obtained by cryogenic technology in addition to normal diet. In both groups the blood concentrations of reduced gluthatione (RG), oxidized gluthatione (OG), gluthatione reductase, gluthatione transferase, gluthatione peroxidase in blood were analyzed three times as well as parameters of cardio-vascular system and effectiveness of activity were examined. Results: low initial RG level was revealed in blood of swimmers. At the same time, RG/OG ratio was 25% lower than optimal in both groups. Towards the end of the study, the ratio significantly (50%) increased in group of sportsmen consumed SNP. The same dynamics was also observed by analyzing indices of effectiveness of activity and pulse rate. Conclusions: dynamics of examined parameters provided evidence that both intensity of physical load and peculiarities of nutrition status may influence on effectiveness of GS function in swimmers. SNP administration increased the effectiveness of activity, but a maximum effect was postponed and was observed in a month after cancelling of its administration

Generation of coherent terahertz pulses in Ruby at room temperature

We have shown that a coherently driven solid state medium can potentially produce strong controllable short pulses of THz radiation. The high efficiency of the technique is based on excitation of maximal THz coherence by applying resonant optical pulses to the medium. The excited coherence in the medium is connected to macroscopic polarization coupled to THz radiation. We have performed detailed simulations by solving the coupled density matrix and Maxwell equations. By using a simple $V$-type energy scheme for ruby, we have demonstrated that the energy of generated THz pulses ranges from hundreds of pico-Joules to nano-Joules at room temperature and micro-Joules at liquid helium temperature, with pulse durations from picoseconds to tens of nanoseconds. We have also suggested a coherent ruby source that lases on two optical wavelengths and simultaneously generates THz radiation. We discussed also possibilities of extension of the technique to different solid-state materials

Comprehensive analysis of the results of surgical treatment of patients with degenerative diseases of the lumbar spine using rigid fixation systems

Introduction. According to the literature, the development of adjacent-level syndrome 10 years after posterior rigid stabilization is noted in 6.7–80 % of patients, of which 24 % require revision surgery.The aim: to conduct a comprehensive analysis of the results of surgical treatment of patients with degenerative diseases of the lumbar spine using rigid fixation systems.Materials and methods. A multicenter retrospective study of the results of surgical treatment of 268 patients with degenerative-dystrophic diseases of the lumbar spine, who underwent mono- or bisegmental decompression-stabilizing intervention with the implementation of the TLIF (Transforaminal Lumbar Interbody Fusion) technique and open transpedicular rigid fixation, was conducted. The study included radiography, MRI and CT (in 2-energy mode) of intervertebral discs and isolated facet degeneration of the upper adjacent level.Results and discussion. The combination of the initial degeneration of the adjacent spinal motion segment in the form of disc degeneration of grade III and higher according to Pfirrmann with threshold values of the density of the outer cartilaginous plate from 161.7 ± 18.8 to 164.8 ± 14.2 HU, the density of the outer facet – from 702.43 ± 12.3 to 713.65 ± 13.6 HU and the density of the inner facet – from 580.5 ± 11.6 to 582.1 ± 15.1 HU, as well as with signs of segmental instability of the adjacent segment can be considered as risk factors for the development of its degeneration. With the progression of degeneration of the upper intervertebral disc, revision interventions were performed within 12–60 months after surgery.Conclusion. Bisegmental stabilization with signs of initial degeneration in the intervertebral disc and facet joints in the upper segment has proven its clinical and instrumental effectiveness in the period of 36 months and reduces the risks of developing degenerative disease of the adjacent disc

Катастрофа голубого неба в системах с неклассическими релаксационными колебаниями

The feasibility of a known blue-sky bifurcation in a class of three-dimensional singularly perturbed systems of ordinary differential equations with one fast and two slow variables is studied. A characteristic property of the considered systems is that they permit so-called nonclassic relaxation oscillations, that is, oscillations with slow components asymptotically close to time-discontinuous functions and a δ-like fast component. Cases when blue-sky bifurcation leads to a relaxation cycle or stable two-dimensional torus are analyzed. Also the question of homoclinic structure emergence is considered.Исследуется вопрос о реализуемости известной бифуркации типа катастрофы голубого неба в некотором классе трехмерных сингулярно возмущенных систем обыкновенных дифференциальных уравнений с одной быстрой и двумя медленными переменными. Характерная особенность рассматриваемых систем состоит в том, что в них происходят так называемые неклассические релаксационные колебания. Таковыми принято называть колебания, у которых медленные компоненты асимптотически близки к некоторым разрывным по времени функциям, а быстрая компонента δ-образна. Разбираются случаи, когда в результате катастрофы голубого неба возникает устойчивый релаксационный цикл или устойчивый двумерный инвариантный тор. Рассматривается также вопрос о появлении гомоклинических структур

Неклассические релаксационные колебания в нейродинамике

A modification of the well-known FitzHugh–Nagumo model from neuroscience is proposed. This model is a singularly perturbed system of ordinary differential equations with a fast variable and a slow one. The existence and stability of a nonclassical relaxation cycle in this system are studied. The slow component of the cycle is asymptotically close to a discontinuous function, while the fast component is a δ-like function. A onedimensional circle of unidirectionally coupled neurons is considered. It is shown the existence of an arbitrarily large number of traveling waves for this chain. In order to illustrate the increasing of the number of stable traveling waves numerical methods were involved.Предлагается новая математическая модель функционирования отдельного нейрона, являющаяся сингулярно возмущенной системой обыкновенных дифференциальных уравнений с одной быстрой и одной медленной переменными и представляющая собой модификацию известной модели ФитцХью–Нагумо. Исследуются вопросы о существовании и устойчивости в рассматриваемой системе так называемого неклассического релаксационного цикла, у которого медленная компонента асимптотически близка к разрывной функции, а быстрая компонента δ-образна. На основе свойств уединенного сингулярно возмущенного генератора изучается динамика континуальной цепочки однонаправленно связанных нейронов. Для полученной цепочки показано существование сколь угодно большого числа бегущих волн. Для иллюстрации наличия у системы нарастающего с уменьшением бифуркационного параметра числа устойчивых бегущих волн привлекались численные методы