Pathogens in Ixodes persulcatus and Ixodes ricinus ticks (Acari, Ixodidae) in Karelia (Russia).

Ixodid ticks (Acarina, Ixodidae) are vectors of dangerous human infections. The main tick species that determine the epidemiological situation for tick-borne diseases in northern Europe are Ixodes ricinus and Ixodes persulcatus. In recent years, significant changes in the number and distribution of these species have been observed, accompanied by an expansion of the sympatric range. This work summarizes the data of long-term studies carried out in Karelia since 2007 on the infection of I. persulcatus and I. ricinus ticks with various pathogens, including new viruses with unclear pathogenic potential. As a result, tick-borne encephalitis virus (TBEV, Siberian genotype), Alongshan virus, several representatives of the family Phenuiviridae, Borrelia afzelii, Borrelia garinii, Ehrlichia muris, Candidatus Rickettsia tarasevichiae and Candidatus Lariskella arthropodarum were identified. Data were obtained on the geographical and temporal variability of tick infection rates with these main pathogens. The average infection rates of I. persulcatus with TBEV and Borrelia burgdorferi sensu lato were 4.4% and 23.4% and those of I. ricinus were 1.1% and 11.9%, respectively. We did not find a correlation between the infection rate of ticks with TBEV, B. burgdorferi s.l. and Ehrlichia muris/chaffeensis with the sex of the vector. In general, the peculiarities of the epidemiological situation in Karelia are determined by the wide distribution and high abundance of I. persulcatus ticks and by their relatively high infection rate with TBEV and B. burgdorferi s.l. in most of the territory, including the periphery of the range.

[The case of the development of ischemic stroke and cerebral edema after SARS-COV-2 infection in a patient with discirculatory encephalopathy and concomitant schizophrenia]. / Sluchai razvitiya ishemicheskogo insul'ta i oteka golovnogo mozga posle infitsirovaniya SARS-CoV-2 na fone distsirkulyatornoi entsefalopatii i soputstvuyushchei shizofrenii.

The article presents a case of ischemic stroke after SARS-CoV-2 infection in a patient with dyscirculatory encephalopathy and schizophrenia. Patient 44 years old, was hospitalized due to a confirmed diagnosis of a new coronavirus infection (COVID-19) and diagnosed bilateral pneumonia with a damage to 65% of the lung parenchyma. The patient has a history of dyscirculatory encephalopathy and paranoid schizophrenia, a continuous type of course. A fatal outcome occurs on the 2nd day of inpatient treatment. A brain autopsy revealed pericellular and perivascular edema, looseness of neuroglia with necrobiotic changes in the brain substance. Neuronal damage, small-focal gliosis, basophilic balls, destructive-productive vasculitis, ischemic small-focus necrosis were revealed. In the lungs, areas of atelectasis, disatelectasis, hyaline membranes, and edematous fluid were found. Epithelium of the convoluted tubules showed dystrophic and necrotic changes. The cause of death of the patient was a new coronavirus infection COVID-19, which caused bilateral viral pneumonia, complicated by the development of acute respiratory failure and COVID-associated ischemic cerebral infarction complicated by neuromorphological changes in the brain.

Effect of Bone Marrow Allotransplantation on Neuron-Specific (NSE) and Histamine-Containing Cells of Lymph Nodes.

The histamine content in bioamine-containing cells and the content of NSE+ cells of the lymph nodes were studied in rats in 40 min and in 2 and 4 h after bone marrow allotransplantation by using the cross luminescence-histochemical method and immunohistochemical method, respectively. Within 2 h after allotransplantation of the bone marrow, a significant increase in histamine content in bioamine-containing cells and an increase in the number of NSE+ cells in the period were observed. Both APUD and NSE+ cells were found to be heterogeneous by staining and luminescence.

Effect of Bone Marrow Autotransplantation on the Numerical Population of Tryptase-Positive Mast Cells, Heparin Sulfation Degree, and Histamine Content.

We studied the effect of bone marrow autotransplantation on the morphofunctional properties and numerical population of mast cells. The experiments were performed on 4-monthold male mice. The animals received an injection of a suspension of bone marrow obtained from the femoral epiphyses of these animals into the caudal vein. In 40 min and 2 h after autotransplantation, the number of tryptase-positive mast cells increased by 1.1 times. The formation of groups of mast cells near erythroid-neutrophil islets and near blood vessels was observed. The proportion of metachromatic mast cells significantly increased. By the degree of mast cells degranulation, we detected non-degranulated up to 48.0±1.4% (vs 55.2±1.2% in intact mice) and moderately degranulated mast cells 22.0±1.2% (vs 18.2±0.9% in intact mice); the percentage of actively degranulated cells was 10.0±0.8% (vs 3.6±0.9% in intact mice; p<0.05). Morphometric parameters of mast cells were changed, with a slight increase in their diameter and distance between the cells. The number of histamine-containing mast cells increased significantly (by 3.2 times in 40 min and by 5.9 times in 2 h) and histamine content in these cells also increased. Thus, bone marrow autotransplantation led to intensification of degranulation and sulfation of mast cells and the release of histamine from them.

Protective immunity spectrum induced by immunization with a vaccine from the TBEV strain Sofjin.

Tick-borne encephalitis (TBE) circulates widely in the territory of Eurasia with up to 10,000 cases registered annually. The TBE virus (TBEV) includes three main subtypes: European, Siberian and Far-Eastern, and two new Asiatic variants, phylogenetically distant from the others. The inactivated antigen of European or Far-Eastern strains is used in commercial TBE vaccines. A set of 14 TBEV strains, isolated in 1937-2008, with different passage histories, representing all subtypes and variants, was used in this work. The chosen set covers almost all the TBE area. Sera of mice, immunized with the TBE vaccine Moscow, prepared from the TBEV strain Sofjin, were studied in a plaque neutralization test against the set of TBEV strains. The vaccine induced antibodies at a protective titer against all TBEV strains and Omsk hemorrhagic fever virus (OHFV) with Е protein amino acid distances of 0.008-0.069, but not against Powassan virus. We showed that after a course of two immunizations, factors such as the period between vaccinations (1-4 weeks), the challenging virus dose (30-1000 LD50) and terms of challenge (1-4 weeks after the last immunization) did not significantly affect the assessment of protective efficacy of the vaccine in vivo. The protective effect of the TBE vaccine Moscow against the set of TBEV strains and the OHFV was demonstrated in in vivo experiments. TBE vaccine Moscow did not protect mice against 10 LD50 of the Powassan virus. We showed that this range of Е protein amino acid distances between the vaccine strain and challenging virus do not have a decisive impact on the TBE vaccine protective effect in vitro and in vivo. Moreover, the TBE vaccine Moscow induces an immune response protective against a wide range of TBEV variants.

[VIBRIO CHOLERAE CHITINOLYTIC COMPLEX:THE COMPOSITION AND THE ROLE IN PERSISTANCE].

Reviewed the paper are the composition and functions of Vibrio cholerae chitinolytic complex which play an important role in the maintaining and creating new forms of vibrios in the environ- ment, it is better adapted to survive in environmental.

[Environmental protection and health of the population at using of a new cotton defoliant «uzdef-k¼ in agriculture].

Toxicity parameters of a new cotton defoliant «UzDEF-K¼ were studied in various ways of exposure. The preparation is established to be referred to the IV hazard class. Hygienic standards of a defoliant in environment objects andfoodstuffs (maximum concentration limit in reservoir's water - 2,0 mg/l, in working zone air - 2,5 mg/m and atmospheric ambient air - 0,2 mg/m were set). Maximum allowable limit in foodstuffs - cotton oil: "it isn't allowed", APC in the soil - 1,15 mg/kg), were scientifically based regulations of safe using of a preparation in agriculture are: a sanitary protection zone-100 m, in terms of attendance at work - 5 days.

Genetic description of a tick-borne encephalitis virus strain Sofjin with the longest history as a vaccine strain.

Vaccines based on the strain Sofjin of the Far-Eastern tick-borne encephalitis virus (TBEV) subtype have been used for TBE prophylaxis for over 50 years in Russia and neighboring countries. On the wide territory, where all known TBEV subtypes are circulating, the cultural, purified, concentrated, inactivated TBE vaccine Moscow has been shown to be safe and efficacious in a massive immunization. In the present work, we describe the genome of the vaccine strain Sofjin. We have shown that it differs from TBEV strains previously published with the name "Sofjin". Moreover, we have shown the stability of the virus during the vaccine manufacturing process on the molecular level.

[Dynamics of the cognitive function in the school-age children presenting with a natal injury to the cervical spine in the course of the combined spa and health resort-based treatment with the use of manual therapy].

AIM: The objective of the present work was to study dynamics of the cognitive function in the school-age children presenting with a natal injury in the cervical region of the spine in the course of the combined spa and health resort-based treatment with the use of manual therapy based at a health resort facility. THE PATIENTS AND METHODS: A total of 110 schoolchildren at the age from 8 to 15 years (mean age 13.0 ± 0.4 years) were examined during the residual period of a natal injury in the cervical region of the spine. All the participants of the study were divided into to randomized groups. The main group was comprised of 55 school-age children (mean age 13.0 ± 0.4 years) given the comprehensive spa and health resort-based treatment with the application of manual therapy and the group of comparison that contained the remaining 55 schoolchildren (mean age 13.0 ± 0.4 years) who received the same balneotherapeutic treatment but without manual therapy. We analyzed the indicators of cognitive function after the application of manual therapy in 55 children and adolescents aged from 8 to 15 years who underwent the natal trauma to the cervical spine associatedwith the symptoms of postural disorders of varying severity. RESULTS AND DISCUSSION: The article presents the results of the analysis of cognitive function dynamics in the children and adolescents under the influence of the combined spa and health resort-based treatment with the use of manual therapy of functional blocks. It was shown that the combined spa and health resort-based rehabilitative treatment with the use of the manual therapeutic techniques makes it possible to significantly improve the condition of the cervical spine and exerts the positive influence on the dynamics of the cognitive function, has beneficial effect on the mental and motor functions, increases the flexibility and backup capabilities of the nervous system, and may be instrumental in resolving the problems arising from school disadaptation.

[Thoracic endometriosis--the rare pathology in thoracic surgery].

Thoracic hematogenic endometriosis is a rare pathology. A clinical course hasn't pathognomic symptoms, because of it, the diagnosis is established due to histological study. The article presented two cases of female patients, who were suffering from thoracic endometriosis. They were hospitalized to the department of thoracic surgery of Municipal multifield hospital No 2 in Saint-Petersburg. The first patient had a posterior mediastinum tumor with asymptomatic disease course. The second patient was with recurrent catamenial pneumothorax.

Prevalence of Kemerovo virus in ixodid ticks from the Russian Federation.

The prevalence of Kemerovo virus in ixodid ticks collected in 2008-2012 from 11 regions of the Russian Federation was investigated by real-time reverse-transcription PCR (RT-PCR). The presence of Kemerovo virus in Ixodes persulcatus, Ixodes ricinus, and Dermacentor reticulatus was confirmed. Virus prevalence depended on the region and varied from zero to 10.1%.

[Peripheral refraction and retinal contour in children with myopia by results of refractometry and partial coherence interferometry].

OBJECTIVE: To determine the posterior pole contour of the eye based on the relative peripheral refractive error and relative eye length. MATERIAL AND METHODS: A parallel study was performed, which enrolled 38 children (76 eyes) with myopia from -1.25 to -10.82 diopters. The patients underwent peripheral refraction assessment with WR-5100K Binocular Auto Refractometer ("Grand Seiko", Japan) and partial coherence tomography with IOLMaster ("Carl Zeiss", Germany) for the relative eye length in areas located 15 and 30 degrees nasal and temporal from the central fovea along the horizontal meridian. RESULTS: In general, refractometry and interferometry showed high coincidence of defocus signs and values for the areas located 15 and 30 degrees nasal as well as 15 degrees temporal from the fovea. However, in 41% of patients defocus signs determined by the two methods mismatched in one or more areas. Most of the mismatch cases were mild myopia. CONCLUSION: We suppose that such a mismatch is caused by optical peculiarities of the anterior eye segment that have an impact on refractometry results.

[System of activation of plasminogen in Vibrio cholerae].

AIM: Study system of activation of plasminogen in Vibrio cholerae. MATERIALS AND METHODS: 75 strains of V. cholerae of various origins were used in the study. Plasminogen was isolated from human plasma by using affinity chromatography on L-lysine sepharose, alpha-enolase activity was determined by a direct method assuming transformation of 2-phosphoglycerate into phopshoenolpyruvate. Vibrios were destroyed by ultrasound disintegrator to isolate membrane Omp protein, intact cells were discarded by centrifugation and cell lysate was centrifugated for 1 hour at 105000 g. The precipitate was solubilized in buffer with 1% triton X-100 and passed through a column with DE-52 cellulose. RESULTS: Vibrio cholerae O1 and O139 strains isolated from clinical specimens and water samples from open water bodies had the ability to bind by using alpha-enolase and transform human plasminogen into plasmin under the effect of outer membrane protein OmpT A protein with molecular weight around 40 kDa had proteolytic activity with a wide specter of substrate specificity, degraded fibrin, gelatin, collagen, protamine and activated plasminogen. Computer analysis showed that OmpT protein of cholera vibrion had a low degree of relation with Enterobacteriaceae omptins. CONCLUSION: The study carried out showed that vibrios have a system of activation of plasminogen that includes at least alpha-enolase and OmpT membrane protein. OmpT protein is assumed to belong to a new class of porins of Vibrionaceae family and its enzymatic activity may play a significant role in pathogenesis of infection.

[Fisiological aspects of host--microorganisms interreaction: the role of neurotransmitter amines].

Ability to use catecholamines as a stimulus for growth and pathogenic activity realization is widespread among bacteria. In the review numerous facts testifying the ability of these substances to stimulate pathogenic microflora development are systematized and mechanisms of growth stimulation and change of genes expression of microorganisms by catecholamines are considered. The microbial endocrinology role in shaping integrative physiological concepts is discussed.

Relationship between proliferative and enzyme activity of hepatocytes in 18-day-old rat pups after mechanical injury to the liver under conditions of stimulation with biogenic compounds.

We studied the effect of bioactive compounds Trepel and Suvar on proliferation and enzyme activity of hepatocytes. It was noted that the bioactive compounds activated enzymes in hepatocytes and stimulated their proliferation after mechanical injury to the liver in 18-day-old rats.

[Dynamics of hepatocyte ploidy changes after mechanical injury of the fetal liver under the conditions of application of biologically active drugs "Trepel" and "suvar"].

The aim of this study was to evaluate the effect of biologically active drugs (BAD) "Trepel" and "Suvar" on the hepatocyte ploidy during the restoration of liver structure in rat fetuses and newborn pups after mechanical injury, inflicted on days 16-17 of intrauterine development (n = 112), and to determine the association of polyploidization with the other manifestations of regeneration. It was found that during the healing of mechanical liver injury in fetuses and newborn rat pups, along with hepatocytes proliferation, their polyploidization occured. This suggests that polyploidization is one of manifestations of a regenerative process. This study has also shown that BAD "Trepel" and "Suvar" activated both hepatocyte proliferation and their polyploidization. The authors believe that the stimulating effect of these substances is associated with their growth-stimulating effect which results in the change in hormonal status of rat organism.

[The detection of capability of Vibrio comma to activate human plasminogen in vitro].

The article discusses the technique of defining the strains of comma bacillus according their capability to convert human plasminogen into plasmin in vitro. This method can be implemented in applied and fundamental research concerning the study of subtle mechanisms of pathogenesis and colonization of intestines under cholera.

[Liver regeneration after its mechanical injury in rats receiving biologically active substances "Trepel" and "Suvar"].

The effect of biologically active substances (BAS) "Trepel" and "Suvar" on liver regeneration 1-30 days after its mechanical injury was studied using histological and morphometric methods in 110 rat pups aged 18 days. The control group comprised 90 animals that received no treatment following liver injury. It was shown that both BAS studied inhibited the inflammatory reaction around the injury focus, suppressed collagenogenesis and activated hepatocyte proliferation.This resulted in the significant substitution of the damaged area by the hepatocytes, that was absent in the control animals. In animals treated with BAS, the numbers of binucleated and mitotically dividing hepatocytes was increased, while the amount of hepatocytes with dystrophic changes was reduced. Authors associate the positive effect of BAS on liver structure regeneration with their growth-promoting activity, resulting in the hypertrophy of different organs, including the thyroid and the adrenal glands, that is accompanied by an excessive production of the respective hormones displaying their physiological actions.

Immortalization and functional characterization of rat arachnoid cell lines.

Modeling the behavior of mammalian arachnoid cells is critical to understand hydrocephalus and other brain disorders involving abnormal flow of cerebrospinal fluid, yet relatively little is known about the physiology of arachnoid cells due to lack of a robust three-dimensional model system. Explanted primary cultures have been the only option to study transport across arachnoid cell membranes, but practical limitations of primary culture include slow growth, early senescence, and poor reproducibility. The purpose of this study was to create immortalized rat arachnoid cell lines to permit in vitro study of arachnoid granulations and properties of cerebrospinal fluid (CSF) flow. We established and partially characterized two immortalized cell lines generated from primary rat arachnoid cells, using retroviral gene transfer of SV40 large T antigen (SV40 LTAg) either with or without human telomerase (hTERT). The established cell lines stably express either SV40 LTAg alone, or SV40 LTAg and hTERT, and demonstrate high proliferative rate, contact inhibition at confluence, and stable expression of protein markers characteristic of native arachnoid cells over more than 160 passages.

GAG-binding variants of tick-borne encephalitis virus.

Previously different authors described various flavivirus mutants with high affinity to cell glycosaminoglycans and low neuroinvasiveness in mice that were obtained consequently passages in cell cultures or in ticks. In present study the analysis of TBEV isolates has shown existence of GAG-binding variants in natural virus population. Affinity to GAG has been evaluated by sorption on heparin-Sepharose. GAG-binding phenotype corresponds to such virus properties, like small plaque phenotype in PEK cells, absence of hemagglutination at pH 6.4, and low neuroinvasiveness in mice. Mutations increasing charge of E protein were necessary but not sufficient for acquisition of GAG-binding phenotype. Molecular modeling and molecular dynamics simulation have shown that the flexibility of E protein molecule could bear influence on the phenotypic manifestation of substitutions increasing charge of the virions.