Splenic morphometric characteristics in infectious mononucleosis (ultrasonic study)

The spleen is a secondary immune and the largest organ of the reticuloendothelial system, actively involved during infectious mononucleosis. Clinically, assessing a degree of organ involvement in the pathological process seems unlikely. As a rule, only palpation and percussion are used to determine the size of the spleen, which represents a late and subjective sign of potential splenomegaly. Ultrasound examination provides ample opportunities to estimate the spleen size during infectious mononucleosis. Our study was aimed at identifying morphometric and Doppler ultrasound changes in the spleen in patients with infectious mononucleosis. Materials and methods. There were enrolled 24 patients with infectious mononucleosis to be compared with 30 healthy medical institute students in control group. All participants underwent splenic ultrasound examination. Spleen echotexture and contour clarity together with measuring linear dimensions: length, width, and thickness were analyzed. Splenic artery and vein velocity parameters were measured at the gates of the spleen. Elastographic window for fibroelastometry was positioned within the window for standard grayscale examination. Measurements were performed at 5 or more points of the spleen parenchyma at least 4—5 mm away from the capsular zone and the zone of large vessels. Based on the morphometric measurements obtained, the mass, spleen mass coefficient (SMC), as well as the spleen mass/body height ratio and spleen mass/body surface area ratio were calculated. Results. We found that patients with infectious mononucleosis had the length, thickness and weight of the spleen significantly greater than those observed in control group. However, the mass of the spleen varies widely and justified to calculate the CMS as an objective criterion to assess the size of the spleen. It was revealed that infectious mononucleosis may proceed in one of the three variants of the splenic response: decreased size, CMR < 1.5; normal size, CMR ranged from 1.5 to 4; splenomegaly, CMR > 4. Splenomegaly is associated with increased organ stiffness, peak blood flow velocity and pressure in v. lienalis, as well as periportal lymphadenopathy. Identified changes are characteristics of young patients. Conclusion. Ultrasound examination of the spleen is of high diagnostic value for patients with infectious mononucleosis allowing highly accurate assessment state of the immune organs in the acute disease period. At the preclinical stage, gradation of splenomegaly is possible depending on its intensity, assessed hemodynamics and organ stiffness

High-Frequency Elastic Coupling at the Interface of van der Waals Nanolayers Imaged by Picosecond Ultrasonics

Although the topography of van de Waals (vdW) layers and heterostructures can be imaged by scanning probe microscopy, high-frequency interface elastic properties are more difficult to assess. These can influence the stability, reliability and performance of electronic devices that require uniform layers and interfaces. Here, we use picosecond ultrasonics to image these properties in vdW layers and heterostructures based on well-known exfoliable materials, i.e. InSe, hBN and graphene. We reveal a strong, uniform elastic coupling between vdW layers over a wide range of frequencies of up to tens of gigahertz (GHz) and in-plane areas of 100 _m2. In contrast, the vdW layers can be weakly coupled to their supporting substrate, behaving effectively as free standing membranes. Our data and analysis demonstrate that picosecond ultrasonics offers opportunities can probe the high-frequency elastic coupling of vdW nanolayers and image both perfect and broken interfaces between different materials over a wide frequency range, as required for future scientific and technological developments

КЛИНИЧЕСКИЙ СЛУЧАЙ БРЮШНОГО ТИФА В КАЛИНИНГРАДСКОЙ ОБЛАСТИ

Currently, on the territory of the Russian Federation, typhoid fever is registered in the form of sporadic cases, primarily due to imported cases when Russians visit epidemiologically unfavorable for typhoid fever in foreign countries. A clinical case of a woman from Kaliningrad, who returned from a tourist trip to India, is given. The erased picture of the disease requires the doctors’ alertness and knowledge of the main clinical variants of the disease course. The study of epidemics and the follow-up to normative documents made it possible to establish the correct diagnosis. The treatment was carried out with a positive result.В настоящее время на территории Российской Федерации брюшной тиф регистрируется в виде единичных спорадических случаев. Прежде всего это связано с завозными случаями при посещении россиянами неблагополучных по брюшному тифу зарубежных стран. Приведен клинический случай заболевания у жительницы г. Калининграда, вернувшейся из туристической поездки в Индию. Стертая картина заболевания требует настороженности врачей и знания основных клинических вариантов течения болезни. Изучение эпидемиологического анамнеза и следование нормативным документам позволили поставить правильный диагноз. Лечение проведено с положительным результатом

Ультразвуковая характеристика иммунных органов у детей с инфекционным мононуклеозом

Diagnostic morphometric criteria for splenomegaly in children with infectious mononucleosis are established using ultrasound. The study included 29 children with infectious mononucleosis. The average age is 11.7 ± 3.5 years. A morphometric measurement of the length, width and thickness of the spleen, elastometry (EM), and lymph nodes were evaluated. The spleen mass was determined by method of O.V. Vozgoment, coefficients: the ratio of spleen mass to body mass (KMS, Km), body length (KI), body surface area (Ks). The average CCM value was 6,47 ± 2,8, the absolute value of the indicator varied from 1,9 to 14,2. According to the CCM, patients are divided into 3 groups: group A – 6 (20,7%), group B – 11 (38%), group C – 12 (41,3%). The average mass of the spleen was 332,5 ± 119.6 g, the CMS – from 7,7 to 14,2, the average value of the indicator – 8,6 ± 1,9. In group B the mass of the spleen, compared with group C is 1,2 times less. In group C the spleen mass is statistically significantly greater compared with groups A and B. In group C, spleen rigidity was increased in 42,9% of cases. The average EM value is 15,8 ± 4,8 kPa. A negative correlation between the average strength between EM and age (r = – 0,65, p = 0,01) was revealed. A direct relationship was found between the mass of the spleen and the CMS, and lymphadenopathy of various localization, often periportal lymph nodes.С использованием метода ультразвуковой диагностики установлены диагностические морфометрические критерии спленомегалии у детей с инфекционным мононуклеозом.Материалы и методы. В исследование включено 29 детей с диагнозом «Инфекционный мононуклеоз». Средний возраст – 11,7±3,5 года. Проведено морфометрическое измерение длины, ширины и толщины селезенки, эластометрия, оценка лимфатических узлов. По методике О.В. Возгомент произведены расчеты массы селезенки и коэффициенты, учитывающие отношение массы селезенки к массе тела (KМС, Km), росту (KI), площади поверхности тела (Ks).Результаты. Средняя величина КМС – 6,47±2,8, абсолютная величина показателя варьировала от 1,9 до 14,2. По КМС пациенты разделены на 3 группы: группа А – 6 (20,7%) детей, группа В – 11 (38%) детей, группа С – 12 (41,3%) пациентов. Средняя масса селезенки составляла 332,5±119,6 г, КМС – от 7,7 до 14,2, средняя величина показателя – 8,6±1,9. Масса селезенки у детей группы А в 2,5 раза меньше, чем в группе В и в 3 раза меньше, по сравнению с детьми группы С. В группе В масса селезенки, по сравнению с группой С, меньше в 1,2 раза. В группе С масса селезенки статистически значимо больше, по сравнению с детьми групп А и В. У пациентов группы С жесткость селезенки повышена в 42,9% случаев. Средняя величина эластометрии составляет 15,8±4,8 кПа. Выявлена отрицательная корреляционная связь средней силы между эластометрией и возрастом (r= – 0,65, р=0,01).Заключение. Выявлена прямая зависимость: чем выше масса селезенки и КМС, тем чаще появляется лимфаденопатия различной локализации, преимущественно увеличение перипортальных лимфатических узлов. Повышение жесткости селезенки характерно для пациентов с КМС более 4.

High electron mobility, quantum Hall effect and anomalous optical response in atomically thin InSe

A decade of intense research on two-dimensional (2D) atomic crystals has revealed that their properties can differ greatly from those of the parent compound. These differences are governed by changes in the band structure due to quantum confinement and are most profound if the underlying lattice symmetry changes. Here we report a high-quality 2D electron gas in few-layer InSe encapsulated in hexagonal boron nitride under an inert atmosphere. Carrier mobilities are found to exceed 103cm2V-1s-1and 104cm2V-1s-1at room and liquid-helium temperatures, respectively, allowing the observation of the fully developed quantum Hall effect. The conduction electrons occupy a single 2D subband and have a small effective mass. Photoluminescence spectroscopy reveals that the bandgap increases by more than 0.5eV with decreasing the thickness from bulk to bilayer InSe. The band-edge optical response vanishes in monolayer InSe, which is attributed to the monolayer's mirror-plane symmetry. Encapsulated 2D InSe expands the family of graphene-like semiconductors and, in terms of quality, is competitive with atomically thin dichalcogenides and black phosphorus.EU, EPSRC. The Royal Societ

CLINICAL EFFICACY AND SAFETY OF SEIZING PAROXYSMS OF ATRIAL FIBRILLATION WITH PROPAPHENON

The study was made to evaluate clinical efficacy, safety and electrophysiological effects of Propaphenon in seizing paroxysms of atrial fibrillation (AF)45 patients have been evaluated, with AF paroxysms lasting up to 48 hours. To restore sinus rhythm (SR) single oral intake of 600 mg Propaphenon (PRO. MED. CS Praha a.s. ) was used. AF paroxysms were seized under the control of ECG Hotter and BP monitoring.Antiarrhythmic effect was evaluated based on the results of dynamics of electrophysiological parameters determined by means of transesophageal heart electrophysiology studies (ТЕ EPS) in 12 patients.A comparative analysis of results obtained has shown that Propanorm is an effective antiarrhythmic drug to treat AF paroxysms. Heart sinus rhythm (SR) restoration takes place in 88. 9 % cases whereas electrophysiological criteria for antiarrhythmic response include: increased value of rate threshold of induction (RTI) by 140 impulses per minute, disappearance of atrial vulnerability zone and prolonged AV node effective refractory period by 50 ms

CLINICAL CASE OF TYPHOID FEVER IN THE KALININGRAD REGION

Currently, on the territory of the Russian Federation, typhoid fever is registered in the form of sporadic cases, primarily due to imported cases when Russians visit epidemiologically unfavorable for typhoid fever in foreign countries. A clinical case of a woman from Kaliningrad, who returned from a tourist trip to India, is given. The erased picture of the disease requires the doctors’ alertness and knowledge of the main clinical variants of the disease course. The study of epidemics and the follow-up to normative documents made it possible to establish the correct diagnosis. The treatment was carried out with a positive result

Halogen-Doped Chevrel Phase Janus Monolayers for Photocatalytic Water Splitting

Chevrel non-van der Waals crystals are promising candidates for the fabrication of novel 2D materials due to their versatile crystal structure formed by covalently bonded (Mo6X8) clusters (X–chalcogen atom). Here, we present a comprehensive theoretical study of the stability and properties of Mo-based Janus 2D structures with Chevrel structures consisting of chalcogen and halogen atoms via density functional theory calculations. Based on the analysis performed, we determined that the S2Mo3I2 monolayer is the most promising structure for overall photocatalytic water-splitting application due to its appropriate band alignment and its ability to absorb visible light. The modulated Raman spectra for the representative structures can serve as a blueprint for future experimental verification of the proposed structures