Pyrazinamide plays an important role in the treatment of tuberculosis. However, the microbiological test for pyrazinamide resistance is more complex and less reliable than testing of susceptibility ...to other anti-tuberculosis drugs due to the need to grow the pathogen at pH 5.5. Identification of mutations that cause resistance to anti-tuberculosis drugs can replace microbiological methods. Mutations in the
pncA
gene are responsible for the main mechanism of the resistance to pyrazinamide and are found in more than 90% of resistant strains. However, the genetic method for determining drug susceptibility is very complex, because mutations leading to pyrazinamide resistance are diverse and scattered throughout the gene. We have developed a software package for automatic data interpretation and prediction of the resistance to pyrazinamide based on Sanger sequencing results. The effectiveness of detection of pyrazinamide resistance in 16 clinical samples was compared using the BACTEC MGIT 960 automated system and
pncA
gene Sanger sequencing with automated analysis of the results. A significant advantage of the developed method over a single microbiological study was shown, due to greater reliability of the results irrespective of the purity of isolates.
Drug acetylation plays an important role in the medical practice. Modern methods of acetylation phenotype prediction are based on genotyping of polymorphisms in the second exon of the gene
NAT2
. ...Some disadvantages of these methods limit their application in the clinical practice. We developed a method of human genotyping based on identification of
NAT2
gene polymorphism
rs1495741
by real-time PCR. This method of genotype determination has a number of advantages: high sensitivity, simplicity, possibility of automated interpretation of the results, and feasibility in clinical laboratories.
The design of a roll-type electrobaromembrane apparatus has been developed, in which a high efficiency of mixing of multicomponent solutions is ensured when separating colloidal process fluids and ...waste water from chemical industries. A method for calculating the total area of membranes in an electrobaromembrane apparatus, taking into account the areas of roll and tubular elements, has been developed.
The measurement of the level of mitochondrial DNA (mtDNA) in the blood is a difficult problem due to high variability of mitochondrial genes, deletions in the mitochondrial genome in some ...pathological conditions, different sources of mtDNA into the bloodstream (mtDNA from tissues, from blood cells,
etc
.). We designed primers and TaqMan probes for highly conserved regions of the
ND1
and
ND2
genes outside the mitochondrial deletions “hot zones”. For standardizing the technique, the true concentration of low-molecular-weight mtDNA was determined by real-time PCR for two targets: a fragment of the
ND2
gene (122 bp) and the
ND1
and
ND2
genes (1198 bp). The sensitivity and specificity of the developed approach were verified on a DNA pool isolated from the blood plasma of healthy donors of various nationalities. The concentration of low-molecular-weight mtDNA in the blood plasma of two patients with COVID-19 was monitored over two weeks of inpatient treatment. A significant increase in the content of low-molecular-weight mtDNA was observed during the first 5 days after hospitalization, followed by a drop to the level of healthy donors. The developed technique makes it possible to assess the blood level of low-molecular-weight mtDNA regardless of the quality of sampling and makes it possible to standardize this biological marker in a wide range of infectious and non-infectious pathologies.
Background and Purpose. In heart failure (HF), metabolic alterations induce skeletal muscle wasting and decrease of exercise capacity and quality of life. The activation of skeletal muscle ...regeneration potential is a prospective strategy to reduce muscle wasting; therefore, the aim of this project was to determine if functional properties of skeletal muscle mesenchymal progenitor cells (SM-MPC) were affected by HF-induced functional and metabolic dysregulations. Methods. Gastrocnemius muscle biopsy samples were obtained from 3 healthy donors (HD) and 12 HF patients to purify mRNA for further analysis and to isolate SM-MPC. Cells were expanded in vitro and characterized by immunocytochemistry and flow cytometry for expression of mesenchymal (CD105/CD73/CD166/CD146/CD140b/CD140a/VIM) and myogenic (Myf5/CD56/MyoG) markers. Cells were induced to differentiate and were then analyzed by immunostaining and Q-PCR to verify the efficiency of differentiation. The expression of genes that control muscle metabolism and development was compared for HD/HF patients in both muscle biopsy and in vitro-differentiated myotubes. Results. The upregulation of MYH3/MYH8/Myf6 detected in HF skeletal muscle along with metabolic alterations indicates chronic pathological activation of the muscle developmental program. SM-MPC isolated from HD and HF patients represented a mixed population that coexpresses both mesenchymal and myogenic markers and differs from AD-MMSC, BM-MMSC, and IMF-MSC. The functional properties of SM-MPC did not differ between HD and HF patients. Conclusion. In the present work, we demonstrate that the metabolic and functional alterations we detected in skeletal muscle from HF patients do not dramatically affect the functional properties of purified and expanded in vitro SM-MPC. We speculate that skeletal muscle progenitor cells are protected by their niche and under beneficial circumstances could contribute to muscle restoration and prevention and treatment of muscle wasting. The potential new therapeutic strategies of HF-induced skeletal muscle wasting should be targeted on both activation of SM-MPC regeneration potential and improvement of skeletal muscle metabolic status to provide a favorable environment for SM-MPC-driven muscle restoration.
Background
. Bedaquiline is a new and promising anti-tuberculosis drug, but longterm use requires resistance. This is due to mutations in the atpE and mmpR genes in M. tuberculosis (MBT).
The aim of ...the research
was to test a system for automated interpretation of results for predicting resistance to bedaquiline by the molecular data.
Materials and methods
. DNA was isolated from strains of M. tuberculosis in the Irkutsk region and Yakutia. The total quantity of DNA samples was 27 strains from Yakutia and 21 strains from the Irkutsk region. The study of MBT genomes was carried out on the DNA previously obtained by the authors in the territories of the Irkutsk region (n = 5), Yakutia (n = 4), Buryatia (n = 3), Zabaykalskiy kray (n = 4) and the Far East (n = 8). We used the BSATool program to detect bedaquiline resistance based on Sanger and genomic data. Sanger sequencing analyzed the atpE and mmpR genes, and whole genome sequencing examined mutations in the same sequences, as well as additionally in mmpL5, mmpS5, Rv0678, Rv1979c, and pepQ.
Results
. Complete agreement between the phenotypic and genotypic analysis of resistance to bedaquiline was found for three strains from Yakutia. One genome with significant mutations to bedaquiline was identified. A conclusion was made about the importance of molecular analysis of target genes with subsequent detection of resistance to bedaquiline in silico.
Relevance
. The article presents an example of using the method of integral assessment of the epidemiological situation of tuberculosis, which is applied to the main statistical criteria as a more ...accurate approach in assessing the manifestation of the epidemic process and identifying «risk areas» within the Siberian Federal District. The essence of the method consists in ranking the statistical indicators used from the minimum values to the maximum values for the entire study period, and further summing the ranks for each indicator. The resulting integral indicator is further used to calculate the generalized visibility coefficient.
Aim
. Argumentation of «risk areas» associated with tuberculosis infection in the Siberian Federal District using a comprehensive assessment of the main epidemiological indicators.
Results and discussion
. A complex assessment of the epidemiological situation of tuberculosis infection on the territory of the Siberian Federal District made it possible to identify regions with an unfavorable epidemiological situation (Novosibirsk and Kemerovo regions, Altai Territory, Irkutsk region and the Republic of Tyva), which require a comprehensive study to determine the causal relationships and risk factors lying in based on the observed deterioration in key epidemiological indicators.
Conclusion
. In terms of risk-based surveillance, regions with an unfavorable epidemiological situation can be designated as «territory zones».
The analysis of satellite images revealed by 25% decrease of the Altai mountains’ glaciation area over last 50 years. In 2008–2017, deglaciation rate increased twice. This tendency is in good ...agreement with an observed increase in the Katun River flow by 9% in 2008–2017 as compared to 1940–1968 (under invariable total precipitation). The analysis of trends of main meteorological parameters based on weather station data and the ERA-Interim reanalysis demonstrated that statistically significant warming in the region occurs only during the warm season and does not exceed 0.5°С/10 years. For this reason, “atmosphere–glaciers” turbulent heat transfer has increased by 4 W/m
2
in last two years, that caused an annual melting layer increase by 100 mm water equivalent (w.e.). However, the main reason for the Altai mountains’ deglaciation is an increase of downward solar radiation flux, which amounted to 5 W/m
2
per decade and increased the melting layer by 365 mm w.e. per year. A positive trend in net radiation agrees well with a decrease in cloud amount, which is associated with an increase in the moisture divergence flux and geopotential height and with the weakening of zonal winds in the middle troposphere.
This review summarizes recently published data on the mechanisms of tumor cell interaction with the tumor microenvironment. Tumor stroma influences the processes of hepatocarcinogenesis, ...epithelial-to-mesenchymal transition, invasion, and metastasis. The tumor microenvironment includes both cellular and noncellular components. Main cellular components of hepatocellular carcinoma (HCC) stroma are tumor-associated fibroblasts, hepatic stellate cells, immune cells, and endothelial cells that produce extracellular components of tumor microenvironment such as extracellular matrix, various proteins, proteolytic enzymes, growth factors, and cytokines. The noncellular components of the stroma modulate signaling pathways in tumor cells and stimulate invasion and metastasis. The tumor microenvironment composition and organization can serve as prognostic factors in HCC pathogenesis. Current approaches in HCC targeted therapy are aimed at creating efficient strategies for interrupting tumor interactions with the stroma. Recent data on the composition and role of the microenvironment in HCC pathogenesis, as well as new developments in antitumor drug design are discussed.
Cross-replicating associations with rs657152 at the 9q34.2c locus and rs11385942 at the 3p21.31 locus found in patients with severe COVID-19 in the Caucasian population require the study of the ...discovered phenomenon in various populations, including as an independent biological marker. Primers and TaqMan probes for PCR discrimination of the A and C alleles in single nucleotide polymorphism (SNP) rs657152 have been developed. The polymorphism of the rs657152 A/C locus was determined in 129 patients with COVID-19 and in a control group of 466 healthy individuals. There were no significant differences in the frequency of distribution of the A and C alleles, 0.47/0.53 and 0.45/0.55, between patients and healthy subjects, respectively. Also, no differences were found in the distribution of alleles in patients with a high viral load in the smear (Ct in the range of 16–25) in comparison with an average and low viral load (Ct in the range of 26–40).
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