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A room temperature line list for the H 2 15 O radioactive isotopologue of the water molecule is computed using the variational nuclear-motion DVR3D program suite and an empirical high-precision potential energy function. The line list consists of rotation-vibrational energies and Einstein-A coefficients, covering a wide spectral range from 0 to 25000 cm -1 and the total angular momenta J up to 30. Estimates of air-broadening coefficients are provided. Experimentally derived energies of H 2 16 O, H 2 17 O and H 2 18 O from the literature are used to provide improved energies for important states with uncertainty estimates for the H 2 15 O. A number of the wmost promising spectroscopic ranges for the detection of H 2 15 O are proposed. The calculated absorption spectrum should be useful for the study gaseous radioactive water at IR region, determining concentration, etc., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jonathan Tennyson reports financial support was provided by Natural Environment Research Council. Boris Voronin reports was provided by State of Sao Paulo Research Foundation. If there are other authors they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Objective: Describe the structure of pathogenic germline variants and clinical and anatomical features in colorectal cancer patients in Moscow., Material and Methods: The whole genome sequencing results of patients with suspected hereditary cancer syndrome were evaluated. All identified genetic variants were validated using Sanger sequencing., Results: The study included 238 patients with colorectal cancer, 41/238 (17.2%) patients have pathogenic germline variants associated with hereditary cancer syndromes or increased cancer risk. Lynch syndrome accounts for 8% of all colorectal cancer cases (19/238), and familial adenomatous polyposis - 1.7% (4/238). 5 new genetic variants were described for the first time in a Russian colorectal cancer patients: MLH1 c.1921dup (p.Leu641fs), APC c.2929C>T (p.Gln977Ter), PMS2 c.327del (p.Ala110LeufsTer2), MSH2 c.1857dup (p. Val620CysfsTer24), ATM c.895G>T (p.Glu299Ter). In 197 of 238 patients, no significant variants were identified or variants with an uncertain clinical underlying cause were identified., Conclusion: According to the results of the study, an earlier manifestation of a malignant neoplasm and a more frequent occurrence of high-grade carcinomas in the presence of pathogenic germline mutations were noted compared to the group of patients without clinically significant varianrs, while in the group with identified mutations, the frequency of regional and distant metastasis was not increased.

Nanoparticles (NPs) of transition metals and their oxides are widely used in industries and exhibit diverse biological activities - from antimicrobial to growth promoting and regulating biofilms. In this study, the concentration-dependent effects of negatively charged metal and metal oxide NPs on the viability and net surface charge of Rhodococcus cells were revealed. Our hypothesis that zeta potential values of bacterial cells approach the zeta potential of NPs with an increase in the concentration of nanoparticles was statistically validated, thus suggesting the accumulation of nanoparticles on the cell surface. Thus, based on the dynamics of zeta potential, it would be possible to predict the accumulation of metal NPs on the cell surface of particular Rhodococcus species. It seemed that more toxic nanometals (e.g. CuO) accumulate more intensively on the bacterial cell wall than less toxic nanometals (Bi, Ni and Co). Physical properties of NPs, such as shape, size, dispersity and zeta potential, were characterized at different nanoparticle concentrations, in order to explain their diverse effects on bacterial viability, cellular charge and adhesion to hydrocarbons. Interestingly, an increase in Rhodococcus adhesion to n -hexadecane was observed in the presence of Cu and CuO NPs, while treatment with Fe 3 O 4 NPs resulted in a decrease in the adhesive activity. The obtained data help to clarify the mechanisms of nano-bio interaction and make it possible to select metal and metal oxide nanoparticles to modify the surface of bacterial cells without toxic effects., Competing Interests: The authors declare no conflict of interest., (© 2022 The Authors.)

The growing industrial and medical use of gold nanoparticles (AuNPs) requires environmentally friendly methods for their production using microbial biosynthesis. The ability of actinobacteria of the genus Rhodococcus to synthesize AuNPs in the presence of chloroauric acid (HAuCl 4 ) was studied. The effect of elevated (0.8-3.2 mM) concentrations of HAuCl 4 on bacterial viability, morphology, and intracellular accumulation of AuNPs by different Rhodococcus species was shown. An increase in surface roughness, a shift of the zeta potential to the positive region, and the formation of cell aggregates of R. erythropolis IEGM 766 and R. ruber IEGM 1135 during nanoparticle synthesis were revealed as bacterial adaptations to toxic effects of HAuCl 4 . The possibility to biosynthesize AuNPs at a five times higher concentration of chloroauric acid compared to chemical synthesis, for example, using the citrate method, suggests greater efficiency of the biological process using Rhodococcus species. The main parameters of biosynthesized AuNPs (size, shape, surface roughness, and surface charge) were characterized using atomic force microscopy, dynamic and electrophoretic light scattering, and also scanning electron microscopy in combination with energy-dispersive spectrometry. Synthesized by R. erythropolis spherical AuNPs have smaller (30-120 nm) dimensions and are positively (12 mV) charged, unlike AuNPs isolated from R. ruber cells (40-200 nm and -22 mV, respectively). Such differences in AuNPs size and surface charge are due to different biomolecules, which originated from Rhodococcus cells and served as capping agents for nanoparticles. Biosynthesized AuNPs showed antimicrobial activity against Gram-positive ( Micrococcus luteus ) and Gram-negative ( Escherichia coli ) bacteria. Due to the positive charge and high dispersion, the synthesized by R . erythropolis AuNPs are promising for biomedicine, whereas the AuNPs formed by R . ruber IEGM 1135 are prone to aggregation and can be used for biotechnological enrichment of gold-bearing ores.

Background: A fast adoption of a non-invasive prenatal testing (NIPT) in clinical practice is a global tendency last years. Firstly, in Russia according a new regulation it was possible to perform a widescale testing of pregnant women in chromosomal abnormality risk. The aim of the study-to assess efficiency of using NIPT as a second-line first trimester screening test in Moscow., Methods: Based on the first trimester combined prenatal screening results 12,700 pregnant women were classified as a high-risk (cut-off ≥ 1:100) and an intermediate-risk (cut-off 1:101 - 1:2500) groups followed by whole genome NIPT. Women from high-risk group and those who had positive NIPT results from intermediate-risk group were considered for invasive prenatal diagnostic., Results: 258 (2.0%) samples with positive NIPT results were detected including 126 cases of trisomy 21 (T21), 40 cases of T18, 12 cases of T13, 41 cases of sex chromosome aneuploidies (SCAs) and 39 cases of rare autosomal aneuploidies (RAAs) and significant copy number variations (CNVs). Statistically significant associations (p < 0.05) were revealed for fetal fraction (FF) and both for some patient's (body mass index and weight) and fetus's (sex and high risk of aneuploidies) characteristics. NIPT showed as a high sensitivity as specificity for common trisomies and SCAs with an overall false positive rate 0.3%., Conclusions: NIPT demonstrated high sensitivity and specificity. As a second-line screening test it has shown a high efficiency in detecting fetus chromosomal anomalies as well as it could potentially lower the number of invasive procedures in pregnant women., (© 2022. The Author(s).)

About 5-10% of malignant neoplasms (MN) are hereditary. Carriers of mutations associated with hereditary tumor syndromes (HTS) are at high risk of developing tumors in childhood and young age and synchronous and metachronous multiple tumors. At the same time, this group of diseases remains mainly an oncological problem, and clinical decisions are made only when MNs are detected in carriers of pathogenic mutations.Individual recommendations for cancer screening, treatment, and prevention should be developed for carriers of mutations associated with HTS to prevent an adverse outcome of the disease. It is essential to identify patients at risk by doctors of all specialties for further referral to medical and genetic counseling with molecular genetic testing (in case of indications). The problems of standardization of enrollment criteria for genetic tests, further tactics of prevention, screening, and treatment of many hereditary oncological diseases remain unsolved.This review was created to inform doctors of various specialties, including endocrinologists, about the HTS. This allows them to get acquainted with main clinical features of specific syndromes, helps to understand the difference between hereditary and non-hereditary cancer, recognize signs of hereditary cancer, and introduce the indications for genetic examination and genetic counseling of the patient. Also, significant differences between international and domestic recommendations on screening measures, diagnosis, and treatment of HTS underline the need to review the existing and develop new algorithms for medical support of patients with HTS.

Objectives: To study the isolates with acquired resistance to bedaquiline and linezolid that were obtained from patients enrolled in a clinical study of a novel therapy regimen for drug-resistant TB in Moscow, Russia., Methods: Linezolid resistance was detected using MGIT 960 with a critical concentration of 1 mg/L. The MIC of bedaquiline was determined using the proportion method. To identify genetic determinants of resistance, sequencing of the mmpR ( Rv0678 ), atpE , atpC , pepQ , Rv1979c , rrl , rplC and rplD loci was performed., Results: A total of 85 isolates from 27 patients with acquired resistance to linezolid and reduced susceptibility to bedaquiline (MIC ≥0.06 mg/L) were tested. Most mutations associated with a high MIC of bedaquiline were found in the mmpR gene. We identified for the first time two patients whose clinical isolates had substitutions D28N and A63V in AtpE, which had previously been found only in in vitro -selected strains. Several patients had isolates with elevated MICs of bedaquiline prior to treatment; four of them also bore mutations in mmpR , indicating the presence of some hidden factors in bedaquiline resistance acquisition. The C154R substitution in ribosomal protein L3 was the most frequent in the linezolid-resistant strains. Mutations in the 23S rRNA gene (g2294a and g2814t) associated with linezolid resistance were also found in two isolates. Heteroresistance was identified in ∼40% of samples, which reflects the complex nature of resistance acquisition., Conclusions: The introduction of novel drugs into treatment must be accompanied by continuous phenotypic susceptibility testing and the analysis of genetic determinants of resistance., (© The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: The goal of this study was to compare the consistency of three assays for the determination of the drug resistance of Mycobacterium tuberculosis (MTB) strains with various resistance profiles isolated from the Moscow region., Methods: A total of 144 MTB clinical isolates with a strong bias toward drug resistance were examined using Bactec MGIT 960, Sensititre MycoTB, and a microarray-based molecular assay TB-TEST to detect substitutions in the rpoB, katG, inhA, ahpC, gyrA, gyrB, rrs, eis, and embB genes that are associated with resistance to rifampin, isoniazid, fluoroquinolones, second-line injectable drugs and ethambutol., Results: The average correlation for the identification of resistant and susceptible isolates using the three methods was approximately 94%. An association of mutations detected with variable resistance levels was shown. We propose a change in the breakpoint minimal inhibitory concentration for kanamycin to less than 5 μg/ml in the Sensititre MycoTB system. A pairwise comparison of the minimal inhibitory concentrations (MICs) of two different drugs revealed an increased correlation in the first-line drug group and a partial correlation in the second-line drug group, reflecting the history of the preferential simultaneous use of drugs from these groups. An increased correlation with the MICs was also observed for drugs sharing common resistance mechanisms., Conclusions: The quantitative measures of phenotypic drug resistance produced by the Sensititre MycoTB and the timely detection of mutations using the TB-TEST assay provide guidance for clinicians for the choice of the appropriate drug regimen., Competing Interests: DG and DZ are from a group of developers that invented the TB-TEST microarray assay and are the only authors of Russian patent #2562866, filed by the Engelhardt Institute of Molecular Biology (EIMB). Currently, the TB-TEST kit is produced and sold by the EIMB spin-off company Biochip-IMB, LLC. DG and DZ earned royalties from patent licensing (in 2015 these royalties comprised approximately $100 US dollars per person). DG and DZ are not employees of the Biochip-IMB company and have no direct commercial or financial relationship with this company. There are not any further patents, products in development or marketed products to declare. Therefore, we declare that this circumstance does not alter the authors' adherence to PLOS ONE policies on sharing data and materials. All other authors have declared that no competing interests exist.

Single crystal sapphire and diamond surfaces are used as planar, atomically flat insulating surfaces, for the deposition of the diacetylene compound 10,12-nonacosadiynoic acid. The surface assembly is compared with results on hexagonal boron nitride (h-BN), highly oriented pyrolytic graphite (HOPG) and MoS 2 surfaces. A perfectly flat-lying monolayer of 10,12-nonacosadiynoic acid self-assembles on h-BN like on HOPG and MoS 2 . On sapphire and oxidized diamond surfaces, we observed assemblies of standing-up molecular layers. Surface assembly is driven by surface electrostatic dipoles. Surface polarity is partially controlled using a hydrogenated diamond surface or totally screened by the deposition of a graphene layer on the sapphire surface. This results in a perfectly flat and organized SAM on graphene, which is ready for on-surface polymerization of long and isolated molecular wires under ambient conditions.

The electrical characterization of single-polymer chains on a surface is an important step towards novel molecular device development. The main challenge is the lack of appropriate atomically flat insulating substrates for fabricating single-polymer chains. Here, using atomic force microscopy, we demonstrate that the (0001) surface of an insulating hexagonal boron nitride (h-BN) substrate leads to a flat-lying self-assembled monolayer of diacetylene compounds. The subsequent heating or ultraviolet irradiation can initiate an on-surface polymerization process leading to the formation of long polydiacetylene chains. The frequency of photo-polymerization occurrence on h-BN(0001) is two orders of magnitude higher than that on graphite(0001). This is explained by the enhanced lifetime of the molecular excited state, because relaxation via the h-BN is suppressed due to a large band gap. We also demonstrate that on-surface polymerization on h-BN(0001) is possible even after the lithography process, which opens up the possibility of further electrical investigations.

The test-system "Sensititre MycoTB" was applied to analyze 159 cultures of M.tuberculosis isolated from patients with tuberculosis. According data of investigation in "Bactec 960" they are identified as cultures with multiple medicinal sensitivity. The detailed analysis of results of application of mentioned test-system (mycoTB) demonstrated that significant part of cultures with multiple medicinal sensitivity is sensitive to anti-tuberculosis pharmaceuticals. The significant part of cultures is characterized by "intermediate" sensitivity/resistance than can be established by mentioned test-system. This data permits enlarging possibilities of chemotherapy of tuberculosis., Competing Interests: The authors declare no conflict of interest.

Aim: Determination of critical concentration for chemotherapy drugs, widely used for tuberculosis treatment, for use in Mycobacterium tuberculosis drug sensitivity results evaluation by Sensititre MycoTB test-system., Materials and Methods: Minimal inhibiting concentration (MIC) of isoniazid, rifampicin, streptomycin, ethambutol, amikacin, kanamycin, ofloxacin and moxifloxacin against conditionally sensitive and conditionally resistant strains of tuberculosis mycobacteria (TBM), isolated from various diagnostic material, obtained from patients with various forms of lung tuberculosis being treated in MCSPCTC hospital and dispensaries for tuberculosis control of Moscow, were studied in Sensititre MycoTB test system., Results: Critical concentration of chemotherapy drugs for MycoTB test system was determined as a result of the obtained MIC values analysis as the minimal concentration that suppressed growth of 95% of sensitive strains and does not obstruct growth of 95% of resistant. The following MIC values were established: streptomycin--1.0, isoniazid--0.25, rifampicin--1.0, ethambutol--4.0, ofloxacin--2.0, moxifloxacin--0.25, kanamycin--2.5 and amikacin- 1.0 µg/ml., Conclusion: The developed critical concentration of the mentioned preparations is currently used for evaluation of sensitivity/ resistance of TBM clinical isolates from MCSPCTC.

The frequency of mutations causing drug resistance in MTB isolates were studied in the respiratory material obtained from TB-patients in the Moscow Region. In izoniazid-resistant isolates, the most prevalent mutation was found to be the Ser315Thr substitution in the katG gene (15.8%) whereas the most frequent mutations in multidrug-resistant isolates were Ser531Leu and Ser315Thr in the rpoB and katG genes (26.3%), or a combination of these two substitutions with a T15 mutation in the inhA gene (5.3%). We compared performance of three molecular assays--"TB-BIOCHIP" ("BIOCHIP-IMB", Ltd, Russia), Xpert MTB/RIF ("Cepheid", USA) and GenoType MTBDRplus ("Hain Life-science", Germany), with the efficiency of luminescent microscopy, and phenotypic drug-suscepibility testing in an automated system BACTEC MGIT 960 (Becton, Disckinson and Company, USA). Xpert MTB/RIF, TB-BIOCHIP and GenoType MTBDRplus detected MTB in sputum in 92, 78 and 49% of all culture-positive cases, respectively. The agreement between standard cultural data and molecular DST results for Xpert MTB/RIF (resistance towards rifampicin), for TB-BIOCHIP and GenoType MTBDRplus (resistance towards rifampicin and izoniazid) amounted to 100, 97 and 100% respectively. Summing up, Xpert MTB/RIF was concluded to be the most efficient assay for primary detection of MTB, whereas the TB-BIOCHIP was shown to be the only molecular assay sensitive enough for simultaneous detection of MTB DNA and for revealing multidrug resistance in sputum (i.e. resistance to both first-line anti-TB drugs, rifampicin and izoniazid).

The purpose of the present study was to analyse mutations in the gyrA and gyrB genes of Mycobacterium tuberculosis and define the possible correlation between these mutations and resistance to levofloxacin (LVX), moxifloxacin (MFX) and gatifloxacin (GAT), based on their MICs. One hundred and forty-two M. tuberculosis clinical isolates were collected from pulmonary tuberculosis patients in the Moscow region. All M. tuberculosis strains were tested for drug susceptibility to rifampicin and isoniazid using the BACTEC MGIT 960 System and to ofloxacin (OFX) using the absolute concentration method on solid Lowenstein-Jensen slants. All in all, 68 strains were selected at random (38 strains were resistant and 30 were susceptible to OFX) for further analysis using the TB-BIOCHIP-2 test system and DNA sequence analysis. The MICs of LVX, MFX and GAT for selected strains were determined using the BACTEC MGIT 960 System. Mutations in the gyrA gene were observed in 36 out of 38 (94.7 %) OFX-resistant M. tuberculosis strains. Asn538Asp and Asp500His substitutions in the gyrB gene only were found in two (5.3 %) strains. Twenty-nine out of 30 OFX-sensitive M. tuberculosis strains had no mutations in either gene. One (3.3 %) OFX-sensitive M. tuberculosis strain carried an Arg485His substitution in gyrB. The results of our investigation showed that there is no clear correlation between the type of mutation in the genes gyrA and gyrB, and the MIC levels of LVX, MFX and GAT for resistant strains. Mutations in gyrA and Asn538Asp, and Asp500His substitutions in gyrB were associated with cross-resistance of M. tuberculosis to fluoroquinolones. The substitution Arg485His in gyrB does not confer resistance to LVX, MFX and GAT in M. tuberculosis.

Electronic structure calculations of microhydrated model chromophores (in their deprotonated anionic forms) of the photoactive yellow and green fluorescent proteins (PYP and GFP) are reported. Electron-detachment and excitation energies as well as binding energies of mono- and dihydrated isomers are computed and analyzed. Microhydration has different effects on the excited and ionized states. In lower-energy planar isomers, the interaction with one water molecule blueshifts the excitation energies by 0.1-0.2 eV, whereas the detachment energies increase by 0.4-0.8 eV. The important consequence is that microhydration by just one water molecule converts the resonance (autoionizing) excited states of the bare chromophores into bound states. In the lower-energy microhydrated clusters, interactions with water have negligible effect on the chromophore geometry; however, we also identified higher-energy dihydrated clusters of PYP in which two water molecules form hydrogen-bonding network connecting the carboxylate and phenolate moieties and the chromophore is strongly distorted resulting in a significant shift of excitation energies (up to 0.6 eV).

Three hundred and two Krasnoyarsk gymnasium students were examined to define criteria for determining the adaptation to high schooling loads. The values of the emotional status and adaptive processes were studied in children with varying resistance and varying mastering capacities; the impact of cardiovascular parameters on their adaptive process was defined The criteria for estimating the adaptation to high schooling loads were the presence or absence of acute chills and neurotic reactions, cardiovascular performance, and psychoemotional status.

Seeding of 117,579 samples of clinical materials at the Central Microbiological Laboratory, Moscow Research and Practical Centre of Tuberculosis, resulted in isolation of 15,786 (13,4%) mycobacterial cultures, with 15,333 (97.1%) ones being identified as M. tuberculosis complex and 490 (3.1%) as non-tuberculosis mycobacteria (NTM). Samples collected in the Moscow region were dominated by MAC, M. kansasii, M. xenopi, and M. fotuitum. Cultivation on solid and liquid media in an automated regime was shown to be optimal for isolation of NTM. Comparison of mycobacteria identification by microbiological methods and by high performance liquid chromatography revealed excellent agreement between the results (96.1%), with the latter technique taking less time to obtain them. Agreement between identification of acid-resistant mycobacterial cultures using the MAIS-dif test system and microbiological methods was estimated at 93.5%. IMS biochips may also be used to detect species composition of myobacteria because only one case of disagreement with the results of microbiological methods was documented in the study of 108 cultures by the two techniques.

The crystal structure, optical absorption, and photoluminescence of chromium impurity centers were studied in nanocrystalline SrTiO(3):Cr (0.1 mol%) powders with average particle size within the range 13-100 nm prepared by the Pechini-type polymeric sol-gel method. Only the presence of a cubic perovskite phase of O(h)(1) symmetry was proved for the powders at room temperature, by means of x-ray diffraction. The lattice constant a = 3.910 Å, larger than that of bulk SrTiO(3) crystals (a = 3.905 Å), was found for nanoparticles with the size about 20 nm. The optical absorption edge and the zero-phonon R-line ([Formula: see text]) of luminescence of the octahedral Cr(3+) centers shifted to higher energies with decreasing nanoparticle size. These size effects were regarded as intrinsic to SrTiO(3). An unusual and large temperature shift of the R-line position very similar to the 'dielectric related' one of the bulk crystals was observed for all powders, evidencing their quantum paraelectric behavior. However, the powders with the average particle size about 13 and 20 nm did not reveal completely reproducible behavior of the R-line position at low temperatures. This instability was considered a possible manifestation of a low-temperature phase transition in small enough SrTiO(3) nanoparticles.

Aim: To develop rapid method of identification of mycobacteria based on laser fluorescence., Materials and Methods: Characteristics of laser-induced fluorescence of 19 bacteria species, including 17 species of mycobacteria, were studied. Identification of microorganisms was performed using measurement of spectral-fluorescent characteristics., Results: Library of spectral-fluorescent characteristics of mycobacteria in different concentrations ratios and associations was created, which formed the basis of database for identification of mycobacteria by laser-fluorescent method. Principles of diagnostic algorithm of indication and differentiation of mycobacteria using this method were developed. Effect of myramistin for increasing the intensity of mycobacteria fluorescence, account of the diffracting characteristics of medium for adjustment of spectral characteristics of mycobacteria and processing of data by factor analysis are needed. Efficacy of the method was 80 - 90%., Conclusion: Principles of rapid identification of mycobacteria and their associations developed on the basis of laser-fluorescent method are experimentally founded and tested on unknown cultures of mycobacteria and objectively prove the possibility to apply this method for express identification of mycobacteria belonging to M. tuberculosis complex as well as non-tuberculous mycobacteria.

Aim: To compare results of isolation of mycobacteria on different growth media., Materials and Methods: From August 2005 to September 2008 Central Bacteriological Laboratory of MSPCTC performed 111,029 inoculations of clinical samples, isolated 14,513 (13.5%) cultures of mycobacteria, of which 14,095 (97.1%) belonged to M. tuberculosis complex and 418 (2.9%)--to non-tuberculous mycobacteria (NTM)., Results: Two thirds of isolated NTM belonged to slowly growing NTM (Ranyon classification), of which bacteria from M. avium complex as well as M. kansasii and M. xenopi predominated. M. fortuitum was the most frequently isolated between rapidly growing NTM., Conclusion: For isolation and identification of NTM the optimal was inoculation on at least 2 media: solid agar (Middlebrook 7H11) or egg medium and liquid medium (Middlebrook 7H9, in automated system BACTEC MGIT 960), each of which has its own advantages.

Aim: To compare results of mycobacteria identification by bacteriologic methods as well as by high-performance liquid chromatography (HPLC)., Materials and Methods: Two hundred and eighty strains of mycobacteria isolated from respiratory specimens and identified by bacteriologic methods and HPLC were studied., Results: It was established that results of HLPC use were highly correlated with results of microbiologic methods of mycobacteria identification: for identification of M. tuberculosis complex the correlation was 97.0%, for nontuberculous (NTM) slowly growing mycobacteria--95.3%, for quickly growing NTM--96.2% (overall--96.1%). Results of identification of mycobacteria by HPLC were ready in significantly shorter time-frame (during 24 hours)., Conclusion: HLPC method could be recommended for identification of mycobacteria in bacteriologic reference laboratories.

The central bacteriological laboratory of the Moscow Research-and-Practical Center for Tuberculosis Control studied the sensitivity of nontuberculous mycobacteria (NTM) to a number of antituberculous drugs (streptomycin, isoniazid, rifampicin, ethambutol, kanamycin, ethionamide, cycloserine, ofloxacin) by the absolute concentration method (after isolating the cultures on both solid and liquid nutrient media). A total of 160 cultures, including M. chelonae (n = 4), M. flavescense (n = 6), M. fortuitum (n = 34), M. avium complex (MAC) (n = 52), M. xenopi (n = 18), M. kansasii (n = 41), M. marinum (n = 2), M. malmoense (n = 1), M. simiae (n = 1), and M. gastri (n = 1), were explored. MAC was found to be resistant to streptomycin, isoniazid, rifampicin, ethambutol, and ethionamide in most cases, to ofloxacin in a nearly half of cases, to canamycin and cycloserine in a third of cases. In most cases, M. kansasii was sensitive not only to first-, but also second-line chemical drugs. M. xenopi was resistant to rifampicin in two thirds of cases and to streptomycin, isoniazid, ethambutol, and ethionamide in a half of cases. This species of NTM was more sensitive to kanamycin, cycloserine, and oflaxacin. In the majority of cases, M. fortuitum was resistant to streptomycin, isoniazid, rifampicin, ethambutol, ethionamide, kanamycin, and cycloserine and sensitive to ofloxacin.

The centralized microbiological laboratory of the Moscow Scientific-and-Practical Center for Tuberculosis Control (MSPCTC) conducted studies to isolate and identify mycobacterial cultures from clinical materials (sputum, bronchial and bronchoalveolar lavages) that had come from Moscow tuberculosis facilities in August 2005 to November 2008. The isolated mycobacterial cultures were identified by microbiological studies, high-performance liquid chromatography, and restriction fragment length polymorphism analysis of the hsp65 gene by means of the MAIS Dif test system developed at the MSPCTC. During the investigation, 117579 inoculations were made; 15786 (13.4%) of mycobacterial cultures were isolated, which included 15333 (97.1%) M. tuberculosis complex (MAC) cultures and 490 non-tuberculous mycobacteria (NTM) ones that amounted to 3.1% of the total number of the mycobacterial cultures isolated in this period. Two thirds of mycobacteria were referred to as slowly growing NTM (according to the Runyon classification; among them there were predominant MAC (32.40%), M. kansasii (14.7%), and M. xenopi (13.9%). Among the rapidly growing mycobacteria, M. fortuitum (21%) and M. chelonae/abscessus complex (6.5%) were isolated. MAC was frequently detected in all the examined administrative districts of the city However, among the slowly growing NTMs, M. kansasii was identified in the South and West districts even at a greater rate; M. xenopi ranked first in the West district. Among the rapidly growing NTM, M. fortuitum was most common in all districts. M. chelonae/abscessus complex was next in the East district (these NTMs were undetectable in other districts).

Two hundred and forty-two mycobacterial cultures isolated from clinical materials on the Lwenstein-Jensen solid medium and 208 cultures in the automatic Bactec MGIT 960 system (on the modified Middlebrook 7H9 liquid medium) were examined. Of them, there was M. tuberculosis (85 and 82, respectively), M. kansasii (26 and 24), MAC (46 and 38), M. xenopi (24 and 20), M. fortuitum (26 and 22), and M. chelonae/abscessus complex (20 and 18). Identification of mycobacterial cultures isolated on the solid medium by microbiological assay and high performance liquid chromatography (HPLC) showed the agreement of results of the cultures isolated on the liquid medium in 95.5 and 97.2%, respectively; that by these techniques revealed rapidly growing nontuberculosis mycobacteria in 95.8 and 95.2% of cases, respectively; slowing growing mycobacteria in 91.7 and 97.8%, and M. tuberculosis in 96.5 and 97.6%. Mycobacterial isolation on the Middlebrook 7H9 liquid medium in the automatic Bactec MGIT-960 system takes a shorter time than that on the solid (Lwenstein-Jensen) medium. The microbiological identification of mycobacteria lasts as long as 3 weeks while the use of HPLC reduces its time to 24 hours. The efficiency of HPCL does not depend on whether mycobacterial cultures are isolated on the solid or liquid media.

The centralized bacteriological laboratory of the Moscow Scientific-and-Practical Center for Tuberculosis Control Department of Public Health of the city of Moscow, examined the susceptibility of non-tuberculous mycobacteria (NTM) isolated and studied on the solid (Levenstein-Jensen) and liquid (Middlebrook 7H9 in the BACTEC-960 automatic system) media. A total of 159 cultures obtained from the solid medium and 132 from the liquid one were studied; of them there were 4 and 5 M. chelonae cultures, respectively, M. flavescense (n=6 and 4), M. fortuitum (n=34 and 28), MAC (n=52 and 44), M. xenopi (17 and 14), M. kansasii (n=41 and 35). Among the slowly-growing NTM, MAC was found to be resistant to streptomycin, isoniazid, rifampicin, and ethambutol in most cases. M. kansasii was sensitive to all basic antituberculous agents (ATAs) in most cases. M. xenopi was resistant to rifampicin in two thirds and to streptomycin, isoniazid, and ethambutol in a half of cases. Among the rapidly growing NTM, M. fortuitum was resistant to the study basic ATAs in most cases. No significant differences were found in the susceptibility/resistance of NTM to the basic ATAs depending on whether they had been isolated and their susceptibility evaluated on the solid and liquid media. Moreover, the duration of the entire study using the liquid medium was 2-3 times shorter.

Weak neurotoxins belong to the superfamily of three-finger toxins from snake venoms. In general, weak toxins have a low toxicity and, contrary to other three-finger toxins, their molecular targets are not well characterized: in vitro tests indicate that these may be nicotinic acetylcholine receptors. Here, we report the influence of intraperitoneal and intravenous injections of weak neurotoxin from Naja kaouthia venom on mouse behaviour. Dose-dependent suppression of orientation-exploration and locomotion activities as well as relatively weak neurotropic effects of weak neurotoxin were observed. The myorelaxation effect suggests a weak antagonistic activity against muscle-type nicotinic acetylcholine receptors. Neurotoxic effects of weak neurotoxin were related to its influence on peripheral nervous system. The symptomatology of the intoxication was shown to resemble that of muscarinic agonists. Our data suggest that, in addition to interaction with nicotinic acetylcholine receptors observed earlier in vitro, weak neurotoxin interacts in vivo with some other molecular targets. The results of behavioural experiments are in accord with the pharmacological profile of weak neurotoxin effects on haemodynamics in mice and rat indicating the involvement of both nicotinic and muscarinic acetylcholine receptors.

The genus Mycobacterium currently comprises more than 90 species of Mycobacterium, of which a third is able to induce human diseases. With a rise in the incidence of diseases induced by non-tuberculosis mycobacteria, tuberculosis caused by M. bovis that is characterized by a severe cause and a high frequency of poor outcomes cannot be remembered. The species of mycobacteria should be identified to establish a diagnosis and to prescribe adequate chemotherapy. For this purpose, cultural, biochemical, chromatographic, and molecular genetic studies are conducted. The present study using the hsp65 gene restriction fragment length polymorphism test on museum mycobacterial strains and strains isolated from the diagnostic material of patients with suspected tuberculosis by means of Hind61 restrictase has provided a clear differentiation of the restriction profiles of MAIS complex mycobacteria and some other species of non-tuberculosis mycobacteria. To determine the species of representatives of M. tuberculosis complex (M. tuberculosis, M. bovis, BCG M. bovis), the authors have successfully used the test system "TUB-dif" developed at the Institute of Molecular Genetics, Russian Academy of Sciences, by applying the chain polymerase reaction of the senX3-regX3 region.

Restriction fragment length polymorphism analysis of hsp65 gene was performed on museum strains of mycobacteria using Hin6I restrictase. Study of restriction profiles allowed us to distinguish mycobacterial species of the MAIS complex and several strains of nontuberculous mycobacteria.

Antisera to several Mycobacterium species (M. bovis, M. avium, M. kansasii and M. smegmatis), capable of reacting with homologous antigen diluted not below 1:16000 in the ELISA test, have been obtained. These antisera have been found to cross-react with other Mycobacterium species. Specific antisera to M. bovis, M. avium, M. kansasii and M. smegmatis have been obtained by the multiple exhaustion method on Mycobacterium antigens giving the maximum cross reaction and used for the isolation of antibodies to these Mycobacterium species. In ELISA exhausted antisera produce reactions in the dilution 1:500. Antisera (antibodies) to M. bovis react with the determinant of the antigen with a molecular weight of 25-26 kD, antisera (antibodies) to M. kansasii react with the determinant of the antigen with a molecular weight of 72 kD, those to M. smegmatis react with the determinant of the antigen with a molecular weight of 38 kD and those to M. avium, with the determinant of the antigen with a molecular weight of 16-18 kD.