Analysis of Toxicity of Recombinant Pneumolysin from Streptococcus pneumoniae.

We studied toxicity of recombinant Streptococcus pneumoniae pneumolysin protein in experiments on mice and its cytopathogenic effect on cultures of Vero green monkey kidney cells and human lung carcinoma A549 cells in vitro. In vivo and in vitro experiments proved the absence of compromised toxicity and direct cytopathogenic action of the recombinant protein.

Experimental rat models for Hashimoto's thyroiditis.

PURPOSE: Hashimoto's thyroiditis (HT) is an autoimmune thyroid disease characterized by T lymphocyte-mediated destruction of thyroid follicles. To study the pathogenesis of HT and the efficacy of new substances for its treatment, an easily obtained and adequate to the human disease experimental model is needed. The aim of our study was to find out whether it is possible to induce experimental autoimmune thyroiditis (EAT) similar to Hashimoto's thyroiditis by injecting with thyroglobulin (Tg) without using agents that enhance its thyroiditogenicity and without taking into account the genetic sensitivity of animals. METHODS: Wistar rats were immunized with freshly isolated rat Tg or porcine Tg. In 8 weeks, histological studies of the thyroid and parathyroid glands were performed. Thyroid function and total serum calcium level were also evaluated. RESULTS: Immunization with both rat and porcine freshly isolated Tg caused T lymphocytic infiltration of the thyroid gland, thyroid follicle atrophy and degradation in Wistar rats. EAT caused by porcine Tg was characterized by greater severity than EAT induced with rat Tg. In 55% of rats with porcine Tg-induced EAT, oxyphilic metaplasia was detected in the parathyroid glands. In addition, low total serum calcium was observed in these rats. CONCLUSION: Two rat models of autoimmune thyroiditis were obtained. EAT caused in Wistar rats by immunization with rat Tg is similar to Hashimoto's thyroiditis. EAT induced with porcine Tg was accompanied by oxyphil cell metaplasia in the parathyroids and hypocalcemia.

[Stroke in children: experience of the Center for the Treatment of Cerebrovascular Diseases in Children and Adolescents in Moscow]. / Insul't u detei: opyt raboty Tsentra po lecheniyu tserebrovaskulyarnykh zabolevanii u detei i podrostkov Moskvy.

OBJECTIVE: To analyze the work of the Center for the Treatment of Cerebrovascular Pathology in Children and Adolescents, operating on the basis of the Morozov Children's City Clinical Hospital of the Moscow Health Department for the period 2018-2021 and to assess the peculiarities of organizing the provision of specialized care to children and adolescents with acute cerebrovascular accident (ACA). MATERIAL AND METHODS: Annual reports of the Center for the period 2018-2021; included children and adolescents aged 1 month to 17 years 11 months 29 days, with new onset ischemic stroke (IS) and hemorrhagic stroke (HS), cerebral venous thrombosis (sinus thrombosis), confirmed clinically and radiologically. RESULTS: Statistical data on stroke and organization of care for children with this pathology in Moscow are presented. The incidence of IS in Moscow for the period 2018-2021 ranged from 1.6 to 2.5 per 100.000 children, HI - from 2.35 to 3.3 per 100.000, sinus thrombosis from 0.5 to 1.38 per 100.000. When assessing the main etiological factors of stroke in The Center for International Pediatric Stroke Research categories, we noted a prevalence of chronic head and neck diseases (20-37%) and chronic systemic conditions (conditions or diseases with known changes in coagulation or vascular structure, including connective tissue dysplasia, genetic, hematological, inflammatory or diseases of the immune system) (15-20%). In addition, data on reperfusion therapy carried out at the Center are presented. From 2018 (first thrombolysis was performed) to 2021, 7.3-14.7% of all patients with IS underwent thrombolysis. CONCLUSION: The experience of functioning of the Center for the Treatment of Cerebrovascular Pathology in Children and Adolescents has shown that the creation of such centers in the regions of the Russian Federation is relevant, but requires taking into account the characteristics of the pediatric population when organizing their work.

[Influence of siRNA complexes on the reproduction of influenza A virus (Orthomyxoviridae: Alphainfluenzavirus) in vivo].

INTRODUCTION: Influenza is one of the most pressing global health problems. Despite the wide range of available anti-influenza drugs, the viral drug resistance is an increasing concern and requires the search for new approaches to overcome it. A promising solution is the development of drugs with action that is based on the inhibition of the activity of cellular genes through RNA interference. AIM: Evaluation in vivo of the preventive potential of miRNAs directed to the cellular genes FLT4, Nup98 and Nup205 against influenza infection. MATERIALS AND METHODS: The A/California/7/09 strain of influenza virus (H1N1) and BALB/c mice were used in the study. The administration of siRNA and experimental infection of animals were performed intranasally. The results of the experiment were analyzed using molecular genetic and virological methods. RESULTS: The use of siRNA complexes Nup98.1 and Nup205.1 led to a significant decrease in viral reproduction and concentration of viral RNA on the 3rd day after infection. When two siRNA complexes (Nup98.1 and Nup205.1) were administered simultaneously, a significant decrease in viral titer and concentration of viral RNA was also noted compared with the control groups. CONCLUSIONS: The use of siRNAs in vivo can lead to an antiviral effect when the activity of single or several cellular genes is suppressed. The results indicate that the use of siRNAs targeting the cellular genes whose expression products are involved in viral reproduction is one of the promising methods for the prevention and treatment of not only influenza, but also other respiratory infections.

Preparation a Recombinant Form of Pneumolysin Protein from Streptococcus pneumoniae.

A recombinant form of pneumolysin from Streptococcus pneumoniae was obtained. By using Vector NTI Advance 11.0 bioinformatic analysis software, specific primers were designed in order to amplify the genome fragment of strain No. 3358 S. pneumoniae serotype 19F containing the nucleotide sequence encoding the full-length pneumolysin protein. A PCR product with a molecular weight corresponding to the nucleotide sequence of the S. pneumoniae genome fragment encoding the full-length pneumolysin was obtained. An expression system for recombinant pneumolysin in E. coli was constructed. Sequencing confirmed the identity of the inserted nucleotide sequence encoding the full-length recombinant pneumolysin synthesized in E. coli M15 strain. Purification of the recombinant protein was performed by affinity chromatography using Ni-Sepharose in 8 M urea buffer solution. Confirmation of the recombinant protein was performed by immunoblotting with monoclonal antibodies to pneumolysin.

[Stroke in children and adolescents]. / Insul't u detei i podrostkov.

OBJECTIVE: A comparative analysis of symptoms in arterial ischemic and stroke-like conditions in children, the development and analysis of the «Presumptive stroke in children¼ scale for prehospital diagnosis of ischemic strokes in children. MATERIAL AND METHODS: This article analyzes cases of emergency hospitalization of children in a stroke center with suspected cerebrovascular pathology as well as the symptoms of patients with suspected ischemic stroke, compares the leading and final diagnoses, identifies the main «mimics¼ of stroke and their symptom complexes. A comparison of the obtained data with the results of previous studies was carried out. RESULTS: The results show the prevalence of motor disorders and coordination disorders in cases of ischemic stroke and cerebral symptoms in cases of stroke-like conditions in children. The most frequent stroke-mimic is migraine. Based on the results of the study, we propose a screening scale for pre-hospital diagnosis of ischemic stroke in children. A preliminary assessment of the effectiveness of the scale using examples of cases of confirmed stroke and stroke-mimic was performed. CONCLUSION: Timely hospitalization of children with stroke can not only reduce mortality, but also use modern diagnostic and treatment methods to reduce the volume of brain damage with a possible complete restoration of motor and cognitive functions. Further analysis of the sensitivity and specificity of the «Presumptive stroke in children¼ scale is required.

Effect of colchicine on physiological and biochemical properties of Rhodococcus qingshengii.

The genus Rhodococcus includes polymorphic non-spore-forming gram-positive bacteria belonging to the class Actinobacteria. Together with Mycobacterium and Corynebacterium, Rhodococcus belongs to the Mycolata group. Due to their relatively high growth rate and ability to form biof ilms, Rhodococcus are a convenient model for studying the effect of biologically active compounds on pathogenic Mycolata. Colchicine was previously found to reduce biof ilm formation by P. carotovorum VKM B-1247 and R. qingshengii VKM Ac-2784D. To understand the mechanism of action of this alkaloid on the bacterial cell, we have studied the change in the fatty acid composition and microviscosity of the R. qingshengii VKM Ac-2784D membrane. Nystatin, which is known to reduce membrane microviscosity, is used as a positive control. It has been found that colchicine at concentrations of 0.01 and 0.03 g/l and nystatin (0.03 g/l) have no signif icant effect on the survival of R. qingshengii VKM Ac-2784D cultivated in a buffered saline solution with 0.5 % glucose (GBSS). However, colchicine (0.03 g/l) signif icantly inhibits biof ilm formation. Rhodococcus cells cultivated for 24 hours in GBSS with colchicine acquire a rounded shape. Colchicine at 0.01 g/l concentration increases C16:1(n-7), C17:0, C20:1(n-9) and C21:0 fatty acids. The microviscosity of the membrane of individual cells was distributed from the lowest to the highest values of the generalized laurdan f luorescence polarization index (GP), which indicates a variety of adaptive responses to this alkaloid. At a higher concentration of colchicine (0.03 g/l) in the membranes of R. qingshengii VKM Ac-2784D cells, the content of saturated fatty acids increases and the content of branched fatty acids decreases. This contributes to an increase in membrane microviscosity, which is conf irmed by the data on the GP f luorescence of laurdan. All of the above indicates that colchicine induces a rearrangement of the Rhodococcus cell membrane, probably in the direction of increasing its microviscosity. This may be one of the reasons for the negative effect of colchicine on the formation of R. qingshengii VKM Ac-2784D biof ilms.

Gasdynamic electron cyclotron ion sources: Basic physics, applications, and diagnostic techniques.

The gasdynamic electron cyclotron resonance (ECR) ion source is a type of the device in which the ionization efficiency is achieved primarily due to a high plasma density. Because of a high particle collision rate, the confinement is determined by a gasdynamic plasma outflow from a magnetic trap. Due to high efficiency of resonant heating, electrons gain energy significantly higher than that in inductively or capacitively coupled plasmas. As a consequence of such a parameter combination, the gasdynamic ECR plasma can be a unique source of low to medium charged ions, providing a high current and an ultimate quality of an ion beam. One of the most demanded directions of its application today is a development of high-current proton injectors for modern accelerators and neutron sources of different intensities. Special plasma parameters allow for the use of diagnostic techniques, traditional for multiply charged ECR plasmas as well as for other types of discharges with a high plasma density. Among the additional techniques, one can mention the methods of numerical simulation and reconstruction of the plasma density and temperature from the parameters of the extracted ion beams. Another point is that the high plasma density makes it possible to measure it from the Stark broadening of hydrogen lines by spectroscopy of plasma emission in the visible range, which is a fairly convenient non-invasive diagnostic method. The present paper discusses the main physical aspects of the gasdynamic ECR plasma, suitable diagnostic techniques, and possibilities and future prospects for its various applications.

Modifications of Long Economic Cycles and Prospects for Global Economic Dynamics in 2021-2050.

The article presents an analysis of the nature and causes of changes observed in the long economic cycles (Kondratieff waves) of global economic development of the first half of the 21st century. The forms of these modifications and the time boundaries of the current long economic cycle are defined. A reduction of the ascending wave of the long economic cycle to 15 years and an expected reduction of the descending wave to 15 years are noted. The reasons for the reduced durations of long economic cycle phases are associated with the proliferation of microelectronic information and communication technology and with the aggravation of global competition by major developing economies. Prospects for global economic dynamics in the next 30 years and possible time boundaries of the next long economic cycle are delineated.

[Quincke's edema or angioedema. A contemporary view of the problem]. / Otek Kvinke ili angionevroticheskii otek. Sovremennyi vzglyad na problemu.

The article describes statistical data on patients with angioedema (AE) in the structure of ambulance services and four large multidisciplinary hospitals with otorhinolaryngological departments of the city of Moscow for 2017. The ratio of the number of calls to the NSR in Moscow for AE to the total number of calls was analyzed; the ratio of the number of calls to the ambulatory system for AE to the total number of calls to patients with allergic reactions; the ratio of patients with AE among the total number of treated patients in 3 hospitals in Moscow; the ratio of patients with AE of the upper respiratory tract (URT) among the total number of patients with AE; the ratio of patients with AE URT among the total number of patients with ENT pathology. As a result of the study, it was found that the share of AE in the structure of emergency calls of ambulance teams (n=3 070 491) was 0.7% (n=20 040) and 38.4% of the total number of calls for allergic reactions (n=giant urticaria 52 153). Patients with AE make up 0.34% (n=919) of the total number of treated patients in hospitals (n=269 980). The proportion of patients in whom AE was manifested with a lesion of URT among patients with AE is 1 1.5%. The frequency of occurrence of AE URT among patients hospitalized with pathology of ENT organs (n=14 395) is 0.7% (n=106).

[Pre-hospital diagnosis of stroke in children. An analysis of the work of the First aid station in Moscow and the primary pediatric stroke center]. / Dogospital'naya diagnostika insul'tov u detei. Analiz raboty sluzhby skoroi meditsinskoi pomoshchi Moskvy i pervichnogo tsentra po lecheniyu tserebrovaskulyarnoi patologii u detei i podrostkov.

OBJECTIVE: The article presents an analysis of pre-hospital diagnosis of stroke in children. MATERIAL AND METHODS: Pediatric Stroke Center of Morozov Children's City Clinical Hospital (Center) for the period from October 2018 to December 2019, 502 cases of hospitalization of children by the First aid Station to the Center with directing diagnoses of ischemic stroke (IS), haemorrhagic stroke (HS), transient ischemic attack (TIA), vertebrobasilar syndrome (VBS) were analysed. RESULTS AND CONCLUSION: TIA was the most prevalent diagnosis made by the First aid station, with the lowest rate of confirmation after further examination in the hospital (7.8%). The higher rates of confirmation were observed for VBS (31.5%), IS (11.2%) and HI (9.1%). The so-called «masks of stroke¼ were diagnosed in 84.3% cases of hospitalizations that was in line with earlier studies, which reported 50 to 93%. Based on the data on the frequency of symptoms, their combinations and specificity, a screening scale for pre-hospital diagnosis of stroke in children was suggested.

[Clinical and psychological features of people with internet dependence: experience of a pilot study]. / Kliniko-psikhopatologicheskie osobennosti lits s internet-zavisimost'yu: opyt pilotnogo issledovaniya.

OBJECTIVE: The prevalence of Internet addiction (IA) is growing steadily, especially among the younger generation. The purpose of this multicenter study was to investigate the socio-demographic characteristics, clinical varieties, and profile of psychopathological symptoms of mental disorders in patients with IA. MATERIAL AND METHODS: The study included 2 groups: the main group consisted of 44 people, aged 16 to 34 years, average age 22.00±0.66 years, 33 (75%) men, 11 (25%) women; the control group included 120 people, aged 19 to 30 years, average age 23.13±0.18 years, 90 (74.3%) men, 30 (26.7%) women. Groups were identified at the testing stage based on the total score on the Chen Internet Addiction Scale (CIAS). The main group included individuals who scored CIAS 65 points or higher. The specially developed Unified Study Card, The Mini international neuropsychiatric interview (MINI), the Hospital Anxiety and Depression Scale (HADS), the Beck Depression Questionnaire (BDI), the Prodromal Questionnaire-16 (PQ-16), the Symptom Checklist-90-Questionnaire Revised (SCL-90-R). RESULTS AND CONCLUSION: There were more people with secondary specialized education and unemployed in the main group. The family burden of addiction and psychiatric disorders did not differ in both groups, and the heredity of somatic diseases was lower in the IA group. In the IA group, a psychiatric diagnosis was made 9 times more often. The severity of affective and anxiety disorders was higher in the IA group, while the risk of psychosis was low that allows considering the symptoms of IA outside the framework of subpsychotic mental disorders. The features of the psychopathological symptoms of IA were: total «tension¼ of the psychopathological profile; a relatively uniform and slightly specific profile of psychopathological symptoms with a certain tendency to the prevalence of personality-related stress manifestations.

Immunization with Recombinant Pneumolysin Induces the Production of Antibodies and Protects Mice in a Model of Systemic Infection Caused by Streptococcus pneumoniae.

Immunogenic and protective activity of recombinant pneumolysin was studied in experiments on male BALB/c mice. The mice were immunized intraperitoneally with recombinant pneumolysin sorbed on Al(OH)3 (200 µg per mouse). In 2 weeks after immunization, the isotypes of antibodies to recombinant pneumolysin in the serum of immunized mice were determined by ELISA. The animals were infected with Streptococcus pneumoniae serotype 3. Immunization with recombinant pneumolysin induced the production of anti-pneumolysin antibodies, mainly of IgG1 subisotype. On day 21 after intraperitoneal infection with S. pneumoniae serotype 3 in a dose of 106 microbial cells, the survival rate of animals immunized with recombinant pneumolysin in a dose of 25 µg/mouse was 67% vs. 0% in the control (p<0.001). Recombinant pneumolysin could be considered as a promising protective antigen for inclusion in the serotype-independent vaccine against S. pneumoniae.

A powerful pulsed "point-like" neutron source based on the high-current ECR ion source.

The paper presents recent results of a "pointlike" neutron source development based on a D-D fusion in a D-loaded target caused by its bombardment with a sharply focused deuterium ion beam. These developments are undergoing at the Institute of Applied Physics of Russian Academy of Sciences in order to study a possibility to create an effective and compact device for fast-neutron radiography. The last experiments with a beam produced by a gasdynamic high-current ECR ion source and its focusing with a magnetic lens demonstrated that 60 mA of deuterium ions may be constricted to a transversal size of ∼1 mm at the focal plane. With a purpose to improve this result in terms of the beam current and its size, a combined electrostatic and magnetic focusing system is proposed and analyzed. It is shown that the combined system may enhance the total beam current and reduce its footprint down to 0.13 mm. All numerical analysis was performed using the IBSimu code.

T lymphocyte dependence of the immune response to immunosuppressive neoantigen-exposing Fc fragments of IgG.

We recently identified a rheumatoid factor associated with autoimmune disease resistance and remission, and have named it regulatory rheumatoid factor (regRF). Epitopes recognized by regRF can be induced in papain Fc fragments of IgG. Immunization of arthritic rats with homologous Fc fragments that expose neoepitopes recognized by regRF reduces the symptoms of collagen-induced arthritis. Therefore, regRF-producing lymphocytes are a promising therapeutic target in arthritis, and Fc fragments are a means of stimulating this target.

Wide-aperture dense plasma fluxes production based on ECR discharge in a single solenoid magnetic field.

Results of experimental investigation of the ECR discharge in a single coil magnetic field as an alternative to rf and helicon discharges for wide-aperture dense plasma fluxes production are presented. A possibility of obtaining wide-aperture high density hydrogen plasma fluxes with homogeneous transverse distribution was demonstrated in such a system. The prospects of using this system for obtaining high current ion beams are discussed.

[Oncolytic Properties of a Mumps Virus Vaccine Strain in Human Melanoma Cell Lines].

The oncolytic potential of the attenuated mumps virus (MV) vaccine strain Leningrad-3 (L-3) was evaluated in a panel of four human metastatic melanoma cell lines. The lines were shown to be susceptible and permissive to MV infection. Efficient MV replication led to death of melanoma cells, but the effect differed among the cell lines. Possible mechanisms mediating the selectivity of MV L-3 towards the cell lines were explored. Replicative and oncolytic activity of MV was found to depend on the expression pattern of type I interferon genes. None of the melanoma cell lines showed induction of expression of the total spectrum of genes required to inhibit virus replication. Based on the results, MV L-3 was assumed to be a promising oncolytic agent for human melanoma cells.

Study of hydrogen ECR plasma in a simple mirror magnetic trap heated by 75 GHz pulsed gyrotron radiation.

Plasma of electron cyclotron resonance (ECR) discharge sustained by millimeter wave radiation is widely used for production of ion beams of different kind. The main trend in ECR ion sources development nowadays is an increase of frequency and power of microwave heating. The most advanced systems use gyrotrons in 24-60 GHz frequency range. In previous studies at IAP RAS it was demonstrated that ECR source SMIS 37 (Simple Mirror Ion Source) with 37.5 GHz heating operating in quasigasdynamic regime of plasma confinement is able to produce proton and deuteron beams with ion current density about 700 mA/cm2. As the next step of these investigations plasma properties of the discharge sustained by 75 GHz radiation have been studied. Plasma density and electron temperature were determined using spectroscopic and Langmuir probe techniques. It was demonstrated that plasma density could reach values close to 1014 cm-3 and that is of great interest for further development of high current ion sources for various applications.

Migration of silver on the nanoporous glasses surface under the action of an electric field.

Experimentally, the formation of micro- and nano-labyrinths in grained silver film on the surface of nanoporous glass was shown. The movement of silver ions from the bulk of the nanoporous glass towards the glass surface gradually occurs under direct current application. A similar effect was observed under direct electron irradiation of grained silver film. The proposed mechanism assumes that observed effects are caused by the formation of "hot spots" with a strong electric field, by ionic field emission of positive silver ions from the small charged nanoparticles and by trapping these ions by large nanoparticles.

[The concentration of cerebral natriuretic peptide in tear and blood serum.]

The natriuretic peptides regulate pressure and water metabolism in human organism. The concentration of N-thermal cerebral natriuretic propeptide (NT-proBNP) in tear and blood serum was analyzed. The sampling included 49 patients divided on three groups. The group I (main) included 14 patients with primary open-angle sub-compensated glaucoma degree I-III. The group II (comparative group) included 15 patients with age-related immature cataract. The group III (control) included volunteers without any visual organ diseases. The concentration of NT-proBNP in tear and blood serum was detected by solid-phase enzyme-linked immunosorbent assay technique using test system NT-proBNP - IFA - BEST¼ («Vektor-Best¼, Russia). The median of content of NT-proBNP in tear turned out to be less than in blood serum in all groups (р1 = 0,00763; р2 = 0,00452; р3 = 0,00029) and made up to in patients with glaucoma 41,3 pg/ml, with cataract - 37.5 pg/ml, in healthy people 0 25.0 pg/ml (inter-quartile range made up to 20-60 pg/ml, 20-65 pg/ml, 10-49,5 pg/ml correspondingly). No differences in concentration of NT-proBNP were established in all groups both for blood serum (p = 0,494) and tear (p = 0,388). The concentration of NT-proBNP in tear correlated with its concentration in blood serum (r = 0,694). However, no dependencies were established from value of intra-ocular pressure (r = 0,168). Therefore, the concentration of NTproBNP in tear is not a perspective laboratory arker for diagnostic of increased intra-ocular pressure and stratification of development of glaucoma.