Modeling of Cerebral Ischemic Stroke in Conscious Rats via Arterial Air Embolization.

The etiological factor of cerebral ischemia in the vast majority of cases is vascular embolism. In the present study we investigated embolism caused by atmospheric air bubbles injected into the internal carotid artery of conscious rats. Immediately after embolism modeling, behavioral abnormalities were observed in the animals, and after 24 h, foci of brain damage were detected. The death of animals was observed within 5 days after embolism. The proposed experimental model of cerebral ischemia in conscious rats is more relevant and better corresponds to real conditions than the model on narcotized animals and allows to perform physiological tests immediately after modeling.

Experimental Model of Cerebral Arterial Air Embolism in Conscious Rats.

In this work, an optimal air supply mode was selected to create a model of cerebral arterial air embolism (CAAE) on conscious male Sprague-Dawley rats (n=49). The efficacy of the selected model (administration of 100 µl/kg of air at a rate of 10 µl/min with an infusion pump) was determined by changes in serum biochemical parameters (cholesterol, alkaline phosphatase, inorganic phosphates, AST, and triglycerides), impaired motor functions in the Rotarod test, and visual assessment of the ischemic foci (staining of frontal sections with 1% triphenyltetrazolium chloride solution) at different terms after AAE. The model of AAE created by us confirmed impairment of coordination and motor function in conscious animals and reproduced the lethal consequences of this condition. The obtained results can serve as the basis for drug testing and the development of new approaches to the treatment of ischemic stroke.

[Nystagmus secondary to albinism with ocular involvement in a female: A diagnostic challenge]. / Nistagmo secundario a albinismo con compromiso ocular en paciente femenina: Un desafío diagnóstico.

INTRODUCTION: Infantile nystagmus is an infrequent condition that represents a diagnostic challenge for the pediatri cian. Albinism is one of its main causes, being difficult to suspect in the absence of evident cutaneous involvement, especially in female patients, due to the inheritance type of ocular albinism. Objec tive: To describe a case of nystagmus secondary to albinism with isolated ocular involvement in a female patient, in order to provide tools for pediatric approach and diagnosis. CLINICAL CASE: Three- weeks-old female patient, without morbid history, referred to a pediatric neurosurgeon and ophthal mologist due to paroxysmal eye movements since 2 weeks of age. The electroencephalogram and brain images were normal. In follow-up monitoring at 3 months, iris translucency, nystagmus, and hypermetropic astigmatism were confirmed. Dermatologic evaluation ruled out cutaneous invol vement. The patient developed cephalic downward inclination and coordination development de lay was confirmed, the patient was handled with corrective lenses and kinesiotherapy. In follow-up monitoring at 3 years, there was an improvement in visual acuity, decreased nystagmus and normal neurodevelopment. The ophthalmological evaluation of both parents was normal and there was no history of nystagmus or albinism in the family. Upon her parents' decision, no genetic study was ca rried out. CONCLUSION: The diagnosis of nystagmus secondary to ocular albinism, even in the absence of cutaneous involvement, is clinical. The genetic study allows confirming the etiology, without being an essential examination, unless family planning is considered. Timely research and multidisciplinary intervention determine a better prognosis.

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.

Highly efficient coupling of crystalline microresonators to integrated photonic waveguides.

Crystalline optical whispering gallery mode resonators made from alkaline earth fluorides can achieve exceptionally large optical finesse, and are used in a variety of applications, from frequency stabilization and narrow linewidth lasers, to low-noise microwave generation or soliton Kerr frequency combs. Here we demonstrate an efficient coupling method to resonators of these materials, which employs photonic integrated waveguides on a chip based on silicon nitride. By converting a mode from silicon nitride to a free-hanging silica waveguide on a silicon chip, coupling to a crystalline resonator is achieved with a high extinction, while preserving a quality factor exceeding 200 million. This compact, heterogeneous integration of ultra-high Q-factor crystalline resonators with photonic waveguides provides a proof of concept for wafer scale integration and robust, compact packaging for a wide range of applications.

Soliton dual frequency combs in crystalline microresonators.

We present a novel compact dual-comb source based on a monolithic optical crystalline MgF2 multi-resonator stack. The coherent soliton combs generated in the two microresonators of the stack with the repetition rate of 12.1 GHz and difference of 1.62 MHz provided after heterodyning a 300 MHz wide radio frequency comb. An analogous system can be used for dual-comb spectroscopy, coherent LIDAR applications, and massively parallel optical communications.

Harmonization of chaos into a soliton in Kerr frequency combs.

Dissipative Kerr solitons have paved the way to broadband and fully coherent optical frequency combs in microresonators. Here, we demonstrate numerically that slow frequency tuning of the pump laser in conjunction with phase or amplitude modulation corresponding to the free spectral range of the microresonator, provides reliable convergence of an initially excited chaotic comb state to a single dissipative Kerr soliton (DKS) state. The efficiency of this approach depends on both frequency tuning speed and modulation depth. The relevance of the proposed method is confirmed experimentally in a MgF2 microresonator.

[Effect of Combined Antihypertensive Therapy With Perindopril and Indapamide on Morpho-Functional Parameters of The Heart, Blood Vessels of Small and Medium Caliber in Patients With Essential Hypertension].

AIM: to study effect of therapy with fixed combination of angiotensin-converting enzyme infibitor and diuretic on structural-functional parameters of the heart and vessels and cognitive function. MATERIAL AND METHODS: We included into this study 30 patients (20 women) with mean age 60.06+/-10.19 years, duration of hypertensive disease 14.7 (3; 32) years, body mass index 31.19+/-3.93 kg/m2, and without history of cerebrovascular diseases. Methods of investigation included clinical examination, measurement of parameters of hemodynamics, electro- and echocardiography. Vascular endothelial function and structural - functional state of finger skin capillary network was studied by photopletismography and video capillaroscopy, respectively. The state of cognitive sphere was evaluated with the help of the Montreal Cognitive Assessment (MoCA) test. RESULTS: We noted improvement of endothelial function of middle caliber arteries and microcirculatory vascular bed (MCVB) (increase of occlusion index at the level of MCVB from 1.4 to 1.8, p<0.00005; increase of density of skin capillary network at rest from 45 to 52 kap/2, p<0.00007); improvement of cognitive function according to changes of MoCA test results (from 23 to 27, p<0,0001). There were no changes of lipid and carbohydrate metabolism, and electrolyte balance. Conclision. The use of fixed of perindopril+indopamide is combination characterized by good tolerability and high results.

[Use of somatostatin analogues in the pancreonecrosis therapy (kliniko-experimental research)]. / Osobennosti primeneniya sinteticheskogo analoga somatostatina v terapii pankreonekroza (kliniko-eksperimental'noe issledovanie).

The article is devoted to the study and optimization of therapeutic strategy in pancreatic necrosis. We studied the effectiveness of clinical application of human somatostatin analog - octreotide in different dosages. Submitted investigationconsists of experimental and clinical parts. MATERIAL AND METHODS: Experimentalmodel of acute destructive pancreatitis onrats of Wistar line with weight of 300±30 gwas reproduced.There were 5 animal groups (one control group and four experimental groups). Experimental animals received oktreotidin different doses. In 2 days there were estimated the blood biochemistryand histopathologic features of liver and pancreas of operated animals. In clinical part there were formed two groups of patients out of selected case histories by a principle of similarity of complex therapy differing in oktreotid doses, namely: 1) pancreatonecrosis patients estimated of 3 to 8 points by Ranson scale in whose treatment regimen oktreotid 300 mkg/day (n=70) dose was included; 2) pancreatonecrosispatients estimated of 3 to 8 points by Ransonin whose treatment regimenoktreoid1200 mkg/day (n=38) was included. There were compared indices of lethal outcomes, average bed-days, and dynamics of laboratory findings, number and volume of surgical procedures. RESULTS AND CONCLUSION: Dose-related effect of a synthetic analogue of somatostatin, acetateoktreotid, was proved. Introduction in complex therapy of pancreatonecrosisthe highest possible authorized doses of oktreotid (1200 mkg/day) is conducive to more favorable course of illness, dynamic reduction of amilazemia, decrease of lethal outcomes and total bed-day, and also, reduction of initial and repeated operative procedures.

Modeling the whispering gallery microresonator-based optical modulator.

We present a theoretical analysis and numerical simulations of an electro-optic double resonant modulator based on interaction of fundamental whispering gallery modes with a radio frequency field in a dielectric microdisk made from electro-optical material. Models of the modulator in two dimensions and three dimensions are developed and compared. Both optical and RF fields are simulated using the finite element method. The magnitude of the effect in such a system may be maximized with an optimum configuration of a microstrip resonator used for radio-frequency coupling.

Effect of a helium and oxygen mixture on physiological parameters of rats with cerebral arterial air embolism.

Introduction: Cerebral arterial air embolism (CAE) is a serious and potentially dangerous condition that can interrupt the blood supply to the brain and cause stroke. One of the promising gas mixtures for emergency treatment of air embolism is an oxygen-helium mixture. Methods: We modeled CAE in awake rats by injecting air into the common carotid artery. Immediately after CAE, animals were either untreated or underwent hyperbaria, oxygen inhalation, heated air inhalation, or helium-oxygen mixture inhalation. Body temperature, locomotor activity, respiratory and cardiovascular parameters were monitored in the animals before CAE modeling, and 3 and 24 h after CAE modeling. Results: After 3 hours of CAE modeling in awake rats, depression of the nervous, cardiovascular and respiratory systems, as well as decreased body temperature were observed. 24 h after CAE modeling multifocal cerebral ischemia was observed. Normobaric helium-oxygen mixture inhalation, on par with hyperbaric treatment, restored body temperature, locomotor activity, respiratory volume, respiratory rate, and blood pressure 3 hours after CAE, and prevented the formation of ischemic brain damage lesions 24 h after CAE. Discussion: Thus, inhalation of a heated oxygen-helium gas mixture (O2 30% and He 70%) immediately after CAE improves the physiological condition of the animals and prevents the foci of ischemic brain damage formation.

Evaluation of the Efficiency of Oxygen-Helium Therapy for Patients with Covid-19-Associated Pneumonia.

This article summarizes the experience of managing patients with COVID-19-associated pneumonia treated in one of the intensive care units of a multidisciplinary hospital with and without a heated oxygen-helium mixture. It has been shown that the use of a heated oxygen-helium mixture in the complex therapy of pneumonia caused by SARS-CoV-2 is effective. A comparative analysis of the clinical manifestations of the disease and the results of laboratory tests in the main and control groups of patients confirm with a high degree of reliability the improvement of blood oxygenation, the normalization of the acid-base balance and the positive dynamics of the main parameters, which ultimately increases the efficacy and reduces the time of treatment.

Simplicity Out of Complexity: Band Structure for W20O58 Superconductor.

The band structure, density of states, and the Fermi surface of a recently discovered superconductor, oxygen-deficient tungsten oxide WO2.9 that is equivalent to W20O58, is studied within the density functional theory (DFT) in the generalized gradient approximation (GGA). Here we show that despite the extremely complicated structure containing 78 atoms in the unit cell, the low-energy band structure is quite feasible. Fermi level is crossed by no more than 10 bands per one spin projection (and even 9 bands per pseudospin projection when the spin-orbit coupling is considered) originating from the t2g 5d-orbitals of tungsten atoms forming zigzag chains. These bands become occupied because of the specific zigzag octahedra distortions. To demonstrate the role of distortions, we compare band structures of W20O58 with the real crystal structure and with the idealized one. We also propose a basis for a minimal low-energy tight-binding model for W20O58.

Epidemiology of maxillofacial trauma in the elderly: A European multicenter study.

INTRODUCTION: The progressive aging of European population seems to determine a change in the epidemiology, incidence and etiology of maxillofacial fractures with an increase in the frequency of old patients sustaining craniofacial trauma. The objective of the present study was to assess the demographic variables, causes, and patterns of facial fractures in elderly population (with 70 years or more). MATERIALS AND METHODS: The data from all geriatric patients (70 years or more) with facial fractures between January 1, 2013, and December 31, 2017, were collected. The following data were recorded for each patient: gender, age, voluptuary habits, comorbidities, etiology, site of facial fractures, synchronous body injuries, Facial Injury Severity Score (FISS). RESULTS: A total of 1334 patients (599 male and 735 female patients) were included in the study. Mean age was 79.3 years, and 66% of patients reported one or more comorbidities. The most frequent cause of injury was fall and zygomatic fractures were the most frequently observed injuries. Falls were associated with a low FISS value (P<.005). Concomitant injuries were observed in 27.3% of patients. Falls were associated with the absence of concomitant injuries. The ninth decade (P<.05) and a high FISS score (P<.005) were associated with concomitant body injuries too. CONCLUSIONS: This study confirms the role of falls in the epidemiology of facial trauma in the elderly, but also highlights the frequency of involvement of females, and the high frequency of zygomatic fractures.

Management of mandibular condylar fractures in patients with atrophic edentulous mandibles.

INTRODUCTION: Treatment of condylar fractures in patients with atrophic edentulous mandibles is a peculiar field that has been little considered in the literature. The aim of the study was to assess the demographic and clinical variables as well as management and outcome of mandibular condylar fractures in edentulous patients with atrophic mandibles that were treated at several European departments of oral and maxillofacial surgery. METHODS: The data of all patients with fractures of the atrophic edentulous mandible from the involved maxillofacial surgical units across Europe between January 1, 2008, and December 31, 2017. Only patients that were diagnosed with condylar fractures of the edentulous atrophic mandible were included. RESULTS: A total of 52 patients met the inclusion criteria and were included in the study: 79% of patients reported one or more comorbidities. Thirty-four unilateral neck or subcondylar fractures, 9 bilateral neck or subcondylar condylar fractures, 7 unilateral head condylar fractures, and 2 bilateral head condylar fractures were diagnosed. No treatment was performed in 37 cases, whereas in 4 patients a closed treatment was decided, and 11 patients underwent open reduction and internal fixation. Outcome was considered to be satisfying in 48 patients, with no complications. CONCLUSIONS: The golden rule still remains that the diagnosis of a subcondylar or neck fracture in an edentulous patient should constitute an indication for open reduction and internal fixation. However, an appropriate choice of management options has to be individualized on a case by case basis, also depending on the patient consent.

OpenPET: A Flexible Electronics System for Radiotracer Imaging.

We present the design for OpenPET, an electronics readout system designed for prototype radiotracer imaging instruments. The critical requirements are that it has sufficient performance, channel count, channel density, and power consumption to service a complete camera, and yet be simple, flexible, and customizable enough to be used with almost any detector or camera design. An important feature of this system is that each analog input is processed independently. Each input can be configured to accept signals of either polarity as well as either differential or ground referenced signals. Each signal is digitized by a continuously sampled ADC, which is processed by an FPGA to extract pulse height information. A leading edge discriminator creates a timing edge that is "time stamped" by a TDC implemented inside the FPGA. This digital information from each channel is sent to an FPGA that services 16 analog channels, and information from multiple channels is processed by this FPGA to perform logic for crystal lookup, DOI calculation, calibration, etc. As all of this processing is controlled by firmware and software, it can be modified / customized easily. The system is open source, meaning that all technical data (specifications, schematics and board layout files, source code, and instructions) will be publicly available.

Relationship between osteoinductive characteristics of biocomposite material and physicochemical characteristics of coating.

The osteoinductive characteristics of hydroxylapatite-based coating with different physicochemical characteristics were studied. The formation of the bone tissue on the studied types of the implant coating differed by the pattern and rate of formation of structural elements of the bone. Clear-cut phase-wise osteogenesis was seen on combined calcium phosphate coating: intense formation of the fibrous interstitial substance (due to cellular structure of hydroxylapatite) and slow maturing of cell elements. Bilayer composite coating provided (during the same period) the formation of more mature connective tissue. This phenomenon can be explained by better bioavailability of the coating material. The properties of combined calcium phosphate coating can be evaluated as mainly osteoconductive, while those of bilayer composite coating as osteoinductive.

[Infrared cold laser radiation as an antimutagen].

Effects of infrared cold laser radiation (IRCLR) on mutagenesis and proliferation of the corneal epithelium were studied with laboratory white mice subjected to instigated circulatory hypoxia of the brain. The experiment was to reveal whether IRCLR influences the frequency of chromosomal rearrangements and to allow calculation of the corneal cells mitotic index for circulatory brain hypoxia. Laser radiation was shown to reconstitute the normal frequency of chromosomal aberrations as well as the mitotic cycle in epithelial cells of the mice cornea. Data of the experiment are promising from the standpoint of antihypoxic use of IRCLR in ophthalmology.

[Use of atomic force microscopy for estimation of the morphometric indices of blood cells].

The possibility of using the atomic-force microscopy for the evaluation of the geometrical characteristics of blood cells has been shown. It has been found by comparing the hemocyte morphometric indices obtained at different modes of scanning that noncontact and semicontact methods are adequate for the estimation of the size and geometry of biological objects. The scanning of cells in the semicontact mode leads to the irreversible deformation of samples.

[Effect of krypton-containing gas mixture on Japanese quail embryo development].

Investigated were effects of gas mixture with up to 3.0 kgs/cm2 of krypton on the embryonic development of domesticated Japanese quail (Coturnix coturnix japonica dom.). Results demonstrated absence of a serious krypton effect on Japanese quail embryos. Development of embryos proceeded in due course; morphometrically the experimental embryos were essentially similar to controls. It should be noted that despite exposure to acute hypoxic hypoxia during the initial 12 hours of development in the krypton-containing gas mixture, viability of quail embryos was high enough which can be ascribed to the krypton protective action. Besides, an additional experiment showed that krypton partial pressure of 5-5.5 kgs/cm2 produces the narcotic effect on adult Japanese quails.