Stereochemistry of seven-membered heterocycles. Communication 18. Graphic processing of dipole moments of cis-2-ARYL-4-R-1,3-Dioxa-5,6-benzocycloheptenes and conformational characteristics of the 4-methyl group

1. By graphic processing of the dipole moments of cis-2-aryl-4-R-1,3-dioxa-5,6-benzo-cycloheptenes replacement of the H atom by Me(Ph) at C-4 was shown not to change the position of chair-twist equilibrium. 2. The chair-chair conformational energy and the enthalpy component of the Ce~Te conformation energy for the 4-methyl group were determined. © 1986 Plenum Publishing Corporation

Spectroscopic studies of compounds containing a P —H bond: 4. Vibrational spectra and conformational multiformity of di- tert-butylphosphorous acid molecules

IR and Raman spectra of liquid di- tert-butylphosphorous acid and its two low-temperature crystalline modifications are studied. It is found that at least three stable conformations of acid molecules can exist in the liquid state. © 1995, Plenum Publishing Corporation. All rights reserved

The impact of stress on the morbidity of university students

The purpose of the study is to confirm or refute the relationship of stress experienced with the incidence of students.Цель исследования – подтвердить или опровергнуть связь испытываемого стресса с частотой заболеваемости студентов

Escherichia coli Strain – Super-Producer of Vibrio cholerae Hemolysin

Objective of this work was the cloning of Vibrio cholerae hlyA gene in a plasmid vector providing expression of foreign genes under the control of T5 promoter, and construction of E. coli strain – super-producer of Vibrio cholerae recombinant hemolysin. Materials and methods. V. cholerae о1 strain served as a DNA donor, pQE30 – as a vector plasmid. The gene was PCR-amplified, cloning was carried out by means of conventional methods, productivity of recombinants and localization of the required protein was determined based on the results of electrophoresis of cell lysates. Results and conclusions. A recombinant plasmid pHlyA, expressing the cloned hlyA gene of Vibrio cholerae El Tor under the control of T5 promoter after IPTG induction, has been constructed. Carrying this plasmid strain E. coli M15[pREP4]pHlyA is the super-producer of hemolysin: the content of the product in whole cell lysates is up to 13 %, and in inclusion bodies – up to 17 % of the total cell proteins. The product of the cloned gene, in spite of the absence of proteolytic processing and presence of the hexahistidine block (6His-tag) at its N-terminus, possesses hemolytic activity towards sheep erythrocytes. 6His-tag will provide for obtaining a purified preparation on specific sorbents with a view to create diagnosticums as well as to study the significance of hemolysin as a pathogenicity/persistence factor. The advantages of this producer are the high output of the required protein, inability of synthesis of any accessory biologically active substances, short-term period of biomass growing (4–6 h including induction) and possibility of culturing without sticking to the guidelines for work with the agents of particularly dangerous infections

Value of determining the cerebrospinal fluid protein markers of amyloidosis and neurodegeneration in the diagnosis of vascular and neurodegenerative cognitive impairments

The article presents data on different forms of moderate cognitive impairments (MCI) and the specific features of their transformation to dementia. Cerebrospinal fluid (CSF) was investigated in 60 patients with the amnestic and neurodynamic types of MCI, in 15 patients with vascular dementia (VD), 50 patients with Alzheimer’s disease (AD), and 23 patients with mixed vascular and neurodegenerative dementia (MVND). The specific features of β-amyloid and τ-protein concentrations were established in the preclinical stages of dementia, which reflects the main components of the pathogenesis of neurodegeneration. In the amnestic form of MCI and AD, there was drastically decreased Aβ-42 and increased τ-protein levels in SCF. As cognitive impairments progressed, there was a rise in the concentration of τ-protein; its level correlated with the severity of dementia. In MND, the level of Aβ-42 was significantly reduced while the concentration of τ-protein was much increased; moreover, to a greater extent than in AD and VD. Cerebrovascular damage and neurodegeneration were related to each other and mutually worsened clinical and pathogenic effects

Major and minor lymphocytes subpopulations in peripheral blood and cerebrospinal fluid of children with meningitis

Introduction. The analysis of current publications indicates at our insufficient understanding of subpopulation composition of lymphocytes in peripheral blood and cerebrospinal fluid (CSF) during pediatric neuroinfectious diseases. It has been found that the main lymphocyte populations are divided into many small (minor) subpopulations.The purpose of this research was to assess percentage of major and minor blood and CSF lymphocyte subsets in children with aseptic viral meningitis (AM) or bacterial purulent meningitis (BM).Materials and methods. Phenotyping of blood and CSF lymphocytes of children aged from 4 months to 17 years diagnosed with AM (n = 86) and BM (n = 39) was carried out by using flow cytometry. As a comparison group, we analyzed peripheral blood and CSF samples collected from children with acute respiratory viral infections (ARVIs) associated with syndrome of meningism (n = 27). There was evaluated percentage of the major cell subpopulations (CD3+ T-lymphocytes, T-helpers — CD3+CD4+ Th, cytotoxic T-lymphocytes — CD3+CD8+ CTL, natural killer cells — CD3-CD16+CD56+ NK, B-cells — CD3-CD19+), as well as minor lymphocyte subsets (double positive (DP) (CD3+CD4+CD8+), double negative (DN) (CD3+CD4-CD8-) T-cells, NKT (CD3+CD16+CD56+), CD3-CD8+ NK, CD3+CD8dim and CD3+CD8 8bright).Results. It was found that the acute period of BM and AM vs. the comparison group (ARVI) was characterized by significant differences in the blood and CSF composition of major and minor lymphocyte subsets. In particular, blood T-cells, Th, CTL, NK, NKT, DN, CD3-CD8+ NK, CD3+CD8bright and CD3+CD8dim dominated in parallel with significantly lowered B-cell frequency in AM vs. BM. In the CSF of children with AM, T-cells and Th prevailed, whereas count of B-cells and CD3-CD8+ NK was lower compared to those in BM. In addition, further differences were revealed in CSF and blood cell subset composition depending on nosological entity, while maintaining differences in some major and minor lymphocyte subpopulations lacked in the comparison group. Calculating the CSF/blood ratio for the major and minor lymphocyte subsets uncovered the prevalence for the majority of cell subpopulations (the coefficients ranged from 1.2 to 16.4) in the CSF of the comparison group (ARVI), except B-cells, NK and CD3-CD8+ NK (coefficients ranged from 0.07 to 0.31). AM and BM were featured with various changes in the CSF/blood ratio found for most of the studied subpopulations in the acute period as well as the recovery phase highlighted with characteristic traits for each nosological form.Conclusion. The data obtained indicate about finding specific features in the activation of systemic and intrathecal immune response during viral and bacterial meningitis in children, which may be used as an additional differential diagnostic criterion

Analysis of Genetic Determination of <I>Vibrio cholerae</I> Tweenase Activity

Studied are Vibrio cholerae of different serogroups on the presence of cef (CHO cell elongating factor) gene and activity against tweens and tributyrin using HDS-agar, prepared on the basis of bakery yeast pancreatic digest. Determined is the fact that all cef-positive strains hydrolyze tweens 20, 40, 60, 80, 85 and all but toxigenic V.cholerae O139, hydrolyze tributyrin. In contrast, non-toxigenic cef-negative strains of O139 serogroup, are active only against the latter. Apparently, the tweenase activity of Vibrio cholerae is provided, partly, by Cef, and the ability to hydrolyze tributyrin is the result of combined activity of Cef and other ferments. Shown is the efficiency of HDS-agar application to determine these characteristics

CLINICAL SIGNIFICANCE OF CYTOKINES SERUM LEVELS IN CHILDREN WITH CHICKEN POX

The serum levels of cytokines IL-1β, IL-8, IL-6, IFNα, IFNγ, IL-4, IL-10 were tested in ELISA in 74 children with different courses of chicken pox. Moderate severity course of chicken pox was accompanied by significant increase of IL-1β, IL-8, IFNα, IFNγ, IL-10 levels, but severe course of infection was associated with cytokine response reduction. Manifestation of varicella-zoster virus encephalitis was accompanied by the rise of IL-1β, IL-6, IFNγ and IL-10 levels during the second week of disease

Subsets of cerebrospinal fluid lymphocytes in acute pediatric respiratory viral infection with meningeal syndrome

Current urgency of studying the intrathecal cellular immune response to infections of central nervous system is determined by limited knowledge on existing data about mechanisms of the brain immune protection in normal and diseased state. Implication of multi-colour flow cytometry in clinical laboratory diagnostics allowed to perform detailed studies of biological liquors, including cerebrospinal fluid (CSF). Currently, however, there are only scarce data on the lymphocyte subpopulations in CSF. Appropriate reference values remain a challenging issue. A study of CSF lymphocyte pool in absence of definite results at previous examination may be a potential way to resolve this problem. These clinical conditions include acute respiratory viral infections (ARVI), presenting with pseudomeningitidis (meningism) syndrome. The aim of this work was to characterize the subsets of lymphocytes from CSF of the children with ARVI with the meningism symptoms in order to get basic (control) values for diagnostics of inflammatory brain diseases. We have studied subpopulation composition of the CSF lymphocytes form in 27 children with ARVI complicated by the meningism (pseudomeningitidis) by means of flow cytometry using FACSCalibur analyzer with BD MultiTEST IMK Kit reagents. The data evaluation was performed with FlowJo software. We have studied relative contents of the main subsets, i.e., total Т cells (CD3+); Т helpers (CD3+CD4+Th); cytotoxic T cells (CD3+CD8+CTL); natural killers (СD3-CD16+CD56+NK); В cells (CD3-CD19+), and minor lymphocyte subpopulations: double-positive (DP) (CD3+CD4+CD8+); double-negative (DN) (CD3+CD4-CD8-) T cells; NKT (СD3+CD16+CD56+); CD3+CD8bright, CD3+CD8dim, CD3-CD8+NK. Statistical evaluation was carried out with standard GraphPad Prism 5 software. Among the main lymphocyte populations in CSF, T cell were predominant (96.2%), as well as their subpopulations, i.e., CD4Th (53.4%), and CD8+CTL (28.2%), with low amounts of NK (2.2%) and B cells (0.7%). The mean relative content of minor subpopulations (DN or DP T cells, and NKT cells) was, respectively, 5.3, 4.0, and 9%. Age dependence was revealed for the contents of major and minor lymphocyte subsets. With advancing age of the children, the relative numbers of CD3+ and CD4+Тh cells in CSF increase, as well as CD4/CD8 ratio, associated with decreased share of NK cells, like as DN and CD3+CD8dimТ cells. The results obtained are reflect some features of lymphocyte pool in CSF of the children without inflammatory process in CNS. Thus, they may be referred as control values (inflammation-free brain disorders) when studying immune pathogenesis of neuroinfections and other inflammatory diseases of CNS in the children from different age groups

Recombinant Escherichia coli Strain with Enhanced Production of Vibrio cholerae Neuraminidase

Objective of this work was cloning of the Vibrio cholerae nanH gene as part of a plasmid vector, providing expression of foreign genes under the control of T5 promoter, and construction of a E. coli strain – producer of V. cholerae recombinant neuraminidase.Materials and methods. V. cholerae о1 strain served as a DNA donor, pQE30 – as a vector plasmid. The gene was PCR-amplifi ed, the cloning was carried out by means of conventional methods, performance of recombinants and localization of the required protein was determined based on the results of electrophoresis of cell lysates. Neuraminidase activity was identifi ed by fl uorescence in ultraviolet light after incubation with specifi c substrate (4-methylumbelliferyl-N-acetylneuraminic acid).Results and discussion. Recombinant plasmid pNanH, containing the cloned gene nanH V. cholerae, has been constructed. The gene is inserted into BamHI-PstI sites of the polylinker of pQE30. Expression of the cloned gene in the producer strain E. coli JM103pNanH occurs under the control of T5 promoter after isopropyl-1-thio-β-D-galactopyranoside (IPTG) induction. The strain shows neuraminidase activity. The recombinant NanH protein is accumulated in the producer’s cells in two forms. The fi rst form, with molecular mass (MM) of 89.5 kDa, is an unprocessed protein with the hexahistidine block (6His-tag) at its N-terminus, it is located in inclusion bodies. Its percentage is 5.6–6.6 % of the total cell proteins. The second one, with MM of 83 kDa, is found in the periplasmic space and corresponds to the mature NanH, its percentage being 3.4–3.8 %. The total percentage of both forms is 9–10 % of total cell proteins, which allows to consider the strain E. coli JM103pNanH to be a super-producer of the required protein. The strain may be used for purifi cation of NanH preparations for construction of specifi c diagnostic, therapeutic and pharmaceutical preparations as well as for investigation of the protein as a virulence/persistence factor of the pathogen