[Features of course of pain syndrome in patients with schwannomatosis]. / Osobennosti techeniya bolevogo sindroma u patsientov s shvannomatozami.

OBJECTIVE: To identify the characteristics of pain syndrome in patients with schwannomas depending on genetic predisposition. MATERIAL AND METHODS: The study included 46 patients with peripheral, spinal and intracranial schwannomas, corresponding to the schwannomatosis phenotype according to the 2022 clinical criteria. All patients underwent sequencing of the LZRT1, Nf2 and SMARCB1 and a copy number study in the NF2. RESULTS: The most severe widespread pain was observed in patients with pathogenic LZRT1 variants, while patients with mosaic variants may not even have local tumor-related pain. Patients with SMARCB1variants may have no pain or have localized pain that responds well to surgical treatment. CONCLUSION: Further studies of the molecular features of schwannomatosis and driver mutations in the pathogenesis of pain are necessary to improve the effectiveness of pain therapy in this group of patients. Schwannomatosis is a disease from the group of neurofibromatosis, manifested by the development of multiple schwannomas. Neuropathic pain is one of the main symptoms characteristic of peripheral schwannomas, however, the severity and prevalence of the pain syndrome does not always correlate with the location of the tumors. According to modern concepts, the key factors influencing the characteristics of the pain syndrome are the target gene and the type of pathogenic variant. The most severe widespread pain is observed in patients with pathogenic variants in the LZRT1 gene, while patients with mosaic variants may not even have local pain associated with tumors. Patients with variants in SMARCB1 may have no pain or localized pain that responds well to surgical treatment.

Spectrum collapse, narrow linewidth, and Bogatov effect in diode lasers locked to high-Q optical microresonators.

We present a novel method allowing high-power single-frequency emission with sub-kHz linewidth from a compact multi-frequency diode laser locked to high-Q optical microresonator. Using high-Q MgF2microresonator and multi-frequency diode laser operating at 1535 nm with the output power of 100 mW and an emission spectrum consisting of approximately 50 lines with MHz linewidth, we observed a spectrum collapse to a single line or several lines with a sub-kHz linewidth and output power power of 50 mW. The Bogatov effect predicted more than 30 years ago was observed and studied in the spectrum of the locked laser. For analysis of the considered effect, original theoretical model taking into account self-injection locking effect, mode competition and Bogatov asymmetric mode interaction was developed and numerical modeling was performed. All numerical results are in a good agreement with our experimental data. Accurate analytical estimations for the parameters critical for the considered effect were obtained. The proposed method may be applied for different types of diode lasers operating in different spectral ranges.

Hemochromatosis - modern condition of the problem.

The iron overload syndrome can be associated with various acquired states and hereditary factors. Hereditary hemochromatosis is the most common genetic disorder. Without therapeutic intervention the disease can lead to the development of life-threatening complications such as cirrhosis, hepatocellular carcinoma. The article presents data on pathogenesis, diagnosis and treatment of hereditary hemochromatosis. Own clinical observation is given.

[Clinical aspects of the service of acute postoperative pain treatment].

PURPOSE OF THE STUDY: To analyze work results of the service of acute postoperative pain treatment in the orthopedic hospital. DISIGN: Single-center retrospective observational cohort study. PATIENTS AND METHODS: We studied 1343 patients underwent total hip arthroplasty (64%), total knee arthroplasty (33%), and revision surgeries (3%). The average age of the patients was 59 ± 12 years, and body mass index was 30 ± 6. All patients received triple pain therapy in postoperative period which included pracetamol, NSA IDs or specific ciclooxygenase-2 inhibitor and epidural analgesia or peripheral blockade and patient controlled intravenous or epidural analgesia. The pain intensity was recorded four times a day--every 6 hours during 2 days after surgeries. RESULTS: All patients received oral or intravenous analgesics. 90% of patients received prolonged epidural infusion, 10%--prolonged block of the femoral nerve after total knee arthroplasty. Patient controlled analgesia was used in 6-10% of patients. Average pain intensity was 20 mm according to VAS. Pain intensity over 40 mm was observed in 8-13% of patients at 1st day after surgery and in 2-15% at 2nd day after surgery. Deep vein thrombosis was found in 5.7% of patients, and bleeding in 0.2%. Length of stay in a hospital after total hip arthroplasty and total knee arthroplasty was 6 ± 2 days and 10 ± 8 days after revision surgeries. CONCLUSIONS: The work of the service of acute postoperative pain treatment in the orthopedic hospital, the use of multimodal treatment protocols and mandatory clinical monitoring provide proper control of postoperative pain, patient satisfaction, and allow to accelerate early recovery and reduce the time of postoperative hospital stay after total replacement of large joints.

[Epidemiological peculiarities of acute respiratory diseases and its prophylaxis in Internal Troops of the Ministry of Internal Affairs].

Acute respiratory diseases is the current problem of the medical service and command of Internal Troops of the Ministry of Internal Affairs. In recent years on the background of increase of contract servicemen the total rate of these infections decreased. However, rate of acute respiratory diseases in conscripts remains high and has a tendency to increase. Due to restricted possibilities of immunization in case of acute respiratory diseases it is necessary to improve the non-specific prophylaxis. The guaranty of sanitary-and-epidemiological safety may be active participation of military-and-professional society in realization of lifesaving measures and safety of military service.

[Coxibs for postoperative analgesia].

Coxibs can be regarded as an effective way of postoperative pain treatment with proven analgesic and opioid-saving effects. When comparing the opioid-saving effect after the large surgical interventions, COX-2 inhibitors are not inferior to NSAIDs and surpass paracetamol. The combination of coxibs and opiate receptors antagonists, as well as epidural analgesia is effective in the frames of multimodal analgesia. The reasonability of coxibs and paracetamol combination is questionable. In patients at risk of gastrointestinal complications development, but with none cardiovascular risk, COX-2 inhibitors are more safe, than the combination of NSAIDs and proton pump inhibitors. Due to no cross-reactivity with aspirin and NSAIDs, coxibs can be recommended to patients with aspirin asthma and related diseases. Specific COX-2 inhibitors prescription is able to inhibit comissure formation after laparotomy, suppressing blood vessels proliferation. It is assumed that the COX-2 inhibitors may inhibit vascular endothelial growth factor of the tumor and so inhibit angiogenesis of solitary tumors and metastases, without affecting the normal endothelium. Thus, today coxibs are not inferior in eficiency to certain opioid analgesics and have improved safety profile compared with traditional NSAIDs. These qualities allow to consider them as a group of non-opioid analgesics for postoperative analgesia.

[PRP-therapy and regular physical load in complex treatment of patients with distal form of arterial occlusion].

In a structure of the cardio-vascular system diseases in Ukraine the part of chronical ischemia of the lower extremities tissues constitutes more than 20%. Due to diffuse affection of the distal parts of arterial bed it is impossible to succeed in performance of a direct" revascularization in 40% of patients. In 60-87% of such patients a severe ischemia of the lower extremities tissues occurs, causing the necessity of their high amputation performance on the hip level. The results of surgical treatment of 36 patients, suffering inoperable types of the peripheral arteries occlusion were analyzed. In 18 patients the algorithm of intraoperative ultrasound duplex scanning was applied, surgical interventions were performed using optimized procedures. As a second stage the PRP-therapy was conducted, since the second post-operative day all the patients have had performed the elaborated complex of physical exercises, directed on the shin and hip muscles strengthening. Optimization of the lower extremities indirect revascularization methods have permitted to increase the rate of the treatment positive results from 55.6 to 88.9%, to reduce the unsatisfactory results rate--from 44.4 to 11.1%. The PRP-therapy and complex of regular physical exercises conduction have promoted the VEGF content enhancement in the blood serum by 15.6%. malleolar-brachial index--by 28.9% in the patients, suffering occlusion of femoro-popliteo-tibial segment. PRP-concentrate constitutes a potent cell biological activator of the VEGF, improves metabolism and microcirculation in muscles and cells of the skin.

[Immunity and cytokine status after surgeries on the large intestine].

The aim of our study was to examine the effect of individual schemes of multimodal analgesia on indicators of immunity and inflammation markers after operations on the colon. Patients of group 1 (n=15) received paracetamol, lornoxicam and epidural ropivacaine, 2nd group of patients (n=15)-paracetamol, epidural ropivacaine and tramadol. Comparison group (n=10) patients underwent patient controlled analgesia by promedol. Before surgery, 1st and 3rd days after surgery we examined the contents of cytokines in plasma: interleukin 12p70, interleukin 10, interleukin 6, and TNF. Before surgery and at 5-7 days after surgery indicators of cellular, fagocytal and humoral immunity were monitored. Before surgery patients with colorectal cancer revealed changes in the indices of different components of immunity, as well as an increase in pro-and anti-inflammatory cytokines compared with healthy donors. Multimodal analgesia in patients after operations on the colon is not accompanied by changes in plasma concentrations of cytokines and parameters of immune status in comparison with monoanalgesia by promedol.

[Spectrophometric analysis of volatile compounds in microorganisms].

A simple modification of a spectrophometric method was proposed for the rapid detection of microorganisms based on their ability either to excrete or to absorb volatile compounds. The method provides the possibility of contactless control for bacterial growth at a concentration above 10(7) cells/ml. In addition, the method allows discriminating mutants of the fungus Neurospora crassa defective in the nitrogen metabolism from the wild type strains. It is likely that nitrite reductase and nitrate reductase enzymes regulated by the nit-2 and nit-6 genes are involved in formation of the water soluble volatile compounds of this organism.

[Comparison of analgesics using two devices for the patient-controlled analgesia].

INTRODUCTION: A pilot unicenter blind placebo-controlled study comparing different analgesics was conducted in parallel groups, by concurrently using two patient-controlled analgesia (PCA) apparatuses in one patient, was conducted Subjects and methods. The study included patients after laparotomy. Group I patients (n=22) were proposed 2 PCA apparati, one of which contained trimeperidine solution and the other did placebo. Group 2 patients (n=17) were proposed 2 PCA apparatuses, one of which contained trimeperidine solution and the other did lornoxycam. PCA was adjusted in the same manner in both apparati. The patients were asked to determine which analgesic is best in providing 24-hour analgesia. RESULTS: There were no differences in the intensity of pain between the groups. The latter did not differ in the number of adverse reactions. Comparison showed no significant differences in the use of trimeperidine between Groups 1 and 2 patients. Among Group 1 patients, 61% considered trimeperidine as the best analgesic and 22% did placebo; 17% called none. Group 2 patients chose trimeperidine in 41% of cases and lornoxycam in 41%, none was called in 18%. CONCLUSION: Comparative assessment of analgesics, by employing 2 PCA apparatuses in one patient, allows evaluation of the efficacy of analgesics added to the conventional methods.

[Investigation of electrophysical properties of Listeria monocytogenes cells during the interaction with monoclonal antibodies].

An electrooptical approach was used in studies of Listeria monocytogenes-antibody binding. An electrooptical analyzer, which has been developed at the State Research Center for Applied Microbiology (Obolensk, Russia), was used as a basic instrument for electrooptical measurements. The analyzer consists of the following modules: a sample preparation module, a mixer, an AC field generator, an EO-flow cell, a microcontroller for transfer of liquid, a thermal system, an operator interface, and an image processor. The sample preparation module includes a unit for an automatic filter changing device and a hydraulic system. Since the AC electrokinetic effects depend on the dielectric properties of bioparticles, their composition, morphology, phenotype, the medium, and the frequency of applied electrical field, the electroorientational spectra were used for discrimination of different types of bacteria, a given type being "controlled" (and identified) by the selective choice of binding agents (antibodies). The measurements were performed using a discrete set of frequencies of the orienting electric field (10, 100, 250, and 500 kHz). During biospecific interactions, an antibody is bound to the microorganism, causing a change in the dielectric properties of the microorganism-antibody complex, and the electrooptic signal reaches its maximum at 100-200 kHz. It was shown that the biospecific interactions of Listeria monocytogenes cells with anti-Listeria antibody in the presence of E. coli K-12, and A. brasilense sp7 significantly change the electrooptical signals. Thus, the determination of the presence of particular bacteria within a mixed sample may be achieved by selection and matching of antibodies specific to individual bacterium types and by comparing the spectra of bacterium in the presence and in the absence of specific binding agent (antibody).

[Bacterial motion in porous media]. / Dvizhenie bakterii v poristykh sredakh.

The motion of chemotactically different Escherichia coli C600, cheB287, and AW405 cells was studied using a column packed with silica gel. The model chemotaxis of bacteria in porous media seems to be adequate to natural bacterial chemotaxis in soils. The porous structure of silica gel prevents interfering convective flows. Silica gel columns make it possible to separate bacterial cells differing in motility and chemotaxis. Relevant physical phenomena are discussed. The concept of fast and slow chemotaxis is considered.

Full-field automated photoelasticity by fourier polarimetry with three wavelengths.

The search for fast, precise, and robust testing techniques remains an important problem in automated full-field photoelasticity. The polarizer-sample-analyzer (PSA)-based three-wavelength polarimetric method presented here employs discrete Fourier analysis and a spectral content unwrapping algorithm to provide completely automatic, simple, fast, and accurate determination of both photoelastic parameters. Fourier analysis of experimental data and a three-wavelength approach reduce the effect of noise and efficiently cope with poor accuracy in regions of both isochromatic and isoclinic maps. Because any polarimetric technique yields the phase value in the principal range of the corresponding trigonometric function, the final step in data processing is phase unwrapping. Because of the good quality of the wrapped phase map and because each point is processed independently, our suggested three-wavelength unwrapping algorithm exhibits a high level of robustness. Unlike some other PSA three-wavelength techniques, the given algorithm here solves the problem of phase unwrapping completely. Specifically, it converts experimentally obtained arccosine-type phase maps directly into full phase value distributions, skipping the step of generating an arctangent-type ramped phase map and resorting to other unwrapping routines for final data processing. The accuracy of the new technique has been estimated with a Babinet-Soleil compensator. Test experiments with the disk in diametric compression and a quartz plate have proved that the technique can be used for precise determination of the isoclinic angle and relative retardation, even for large values of the latter.

Specific binding of ethanol to cholesterol in organic solvents.

Although ethanol has been reported to affect cholesterol homeostasis in biological membranes, the molecular mechanism of action is unknown. Here, nuclear magnetic resonance (NMR) spectroscopic techniques have been used to investigate possible direct interactions between ethanol and cholesterol in various low dielectric solvents (acetone, methanol, isopropanol, DMF, DMSO, chloroform, and CCl(4)). Measurement of (13)C chemical shifts, spin-lattice and multiplet relaxation times, as well as self-diffusion coefficients, indicates that ethanol interacts weakly, yet specifically, with the HC-OH moiety and the two flanking methylenes in the cyclohexanol ring of cholesterol. This interaction is most strong in the least polar-solvent carbon tetrachloride where the ethanol-cholesterol equilibrium dissociation constant is estimated to be 2 x 10(-3) M. (13)C-NMR spin-lattice relaxation studies allow insight into the geometry of this complex, which is best modeled with the methyl group of ethanol sandwiched between the two methylenes in the cyclohexanol ring and the hydroxyl group of ethanol hydrogen bonded to the hydroxyl group of cholesterol.

The influence of walking speed on dynamic loading on the human musculoskeletal system.

PURPOSE: A study was conducted to investigate the effects of walking speed on the magnitude of the heel strike initiated shock waves that propagate throughout the human musculoskeletal system. METHODS: Subjects walking on a treadmill at various speeds were used to acquire the experimental data regarding the heel strike-initiated shock waves. Fifteen young healthy men participated in this study. Each one walked on the treadmill at five various speeds, and their associated cadences, while the heel strike induced shock waves were recorded at the tibial tuberosity for each speed during a 16-s period at a sampling rate of 1 kHz. RESULTS: The obtained data reveal a significant increase in the dynamic loading experienced by the human musculoskeletal system with an increase in the walking speed. CONCLUSION: The analysis of the recorded acceleration suggests that an increase in walking speed contributes to an increase in dynamic loading on the human musculoskeletal system. Further, the evidence indicates that dynamic loading increases with the increase in speed at five times the rate of the ground reaction force increase.

[Content of components of the renin-angiotensin-aldosterone system of blood plasma of healthy children in the early neonatal period]. / Soderzhanie komponentov renin-angiotenzin-al'dosteronovoi sistemy v plazme krovi zdorovykh detei v rannem neonatal'nom periode.

The dynamics of the renin and angiotensin converting ferment activity and of the aldosterone concentration in the plasma of blood by healthy newborn full-term in the first week of the life after the birth was determined. The normative values of the studied indexes were obtained. The researches have shown the considerable functional tension of the renin-angiotensin-aldosterone system, that has a very important signification for optimal course of adaptation and anabolic processes by the children at the very beginning of the postnatal development.

A comparison of the effect of shoes on human tibial axial strains recorded during dynamic loading.

Percutaneous axial extensometers were mounted on the medial cortex of the midtibial diaphysis in seven male volunteers and the effect of three different shoes on in vivo peak-to-peak axial compression-tension strains measured during dynamic loading. Zohar shoes had lower axial strains and strain rates during treadmill walking than Nike Air Max running shoes or Israeli infantry boots. During running on a running track, there was no statistically significant difference between the axial strains or strain rates between the shoes tested. Shoe gear can modify tibial strains and strain rates that contribute to the development of tibial stress fractures.