Investigation of the mechanisms underlying retinal photodamage occurring during vitreoretinal interventions is a topical issue of ophtalmology. The study aimed to assess the effect of endoillumination of varying intensity and duration on alteration of oxidative processes in rabbit blood. The experiment involved 16 rabbits, with their retinas exposed to endoillumination of different duration (30 and 60 min) and intensity (8 and 16 cd/m2). Blood samples were collected from the rabbits’ ear vein before and after light exposure. Whole blood and serum biochemiluminescence was measured in order to assess oxidative processes. The data were analyzed using the Mann–Whitney U-test, and the results were considered significant at p ≤ 0.05. A 30-minute light exposure resulted in a significant increase in whole blood biochemiluminescence: 1.5-fold at the intensity of 8 cd/m2 and 2.5-fold at the intensity of 16 cd/m2 relative to control values (p < 0.05), indicating enhanced reactive oxygen species generation by blood cells. In contrast, a significant decrease in serum biochemiluminescence was revealed: 1.2-fold at the intensity of 8 cd/m2 and 2-fold at the intensity of 16 cd/m2 compared to control (p < 0.05) , which likely indicates a compensatory increase in antioxidant activity in response to hyperactivation of free radical processes. With the 60-minute exposure, the changes in biochemiluminescence were more pronounced: 3- and 7-fold increase in whole blood biochemiluminescence and 2- and 3-fold decrease in serum biochemiluminescence, respectively. Thus, intense light exposure resulted in the oxidative process alterations determined by the intensity and duration of exposure.
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Colorectal cancer (CRC) is one of the most prevalent malignant neoplasms that occupies the leading position in terms of cancer mortality. The main problem of CRC is that the disease is diagnosed at the advanced stages (about 50% of cases identified are stage III and IV CRC), which results in high mortality. Dysbiotic gut microbiota alterations represent one of the key risk factors of CRC. Three hypotheses of CRC emergence were formulated in order to explain the relationship between dysbiosis and carcinogenesis: “alpha-bug”, keystone pathogen, and driver–passenger hypotheses. The driver–passenger model is the most promising, it divides bacteria into “drivers” of cancer triggering inflammation and cell damage and the passenger bacteria modeling tumor microenvironment, accelerating tumor growth, and exacerbating dysbiosis. Drivers and passengers can be markers of various carcinogenesis stages. Colonoscopy involving examination of the surface of the rectum and colon is the most effective method to detect CRC, including the early stage disease. However, the wide use of this procedure is limited by the fact that it is associated with discomfort for patients and the risk of possible sequelae. Non-invasive microbiota assessment based on the driver–passenger model can become a safe and affordable alternative to the invasive diagnostics during preventive screening, since it makes it possible to improve survival rate due to involvement of a larger number of patients.
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Human MxA protein induced by type I and III interferons is an important innate immunity mediator, it shows antiviral activity against a broad spectrum of RNA and DNA viruses. According to the latest data, the MxA protein overexpression increases chemotherapy sensitivity and represents one of the favorable prognostic factors in patients with breast cancer. The exogenous mRNA capable of intracellular MxA protein production not only has the potential for treatment of viral respiratory infection, but also can become an important fundamental research tool. The study aimed to construct and produce the exogenous mRNA encoding the functional human cytoplasmic MxA protein by in vitro transcription (IVT); to study its translational properties; to assess and identify the patterns of the expression of some interferon system genes in response to introduction of this exogenous mRNA into cells. As a result of the study, the exogenous mRNAs capable of effective translation (up to 20 ng/mL of protein from 100 ng of mRNA per well of the 96-well plate) in the eukaryotic cell systems were successfully constructed and produced by IVT (in the amount of up to 200 µg); diffuse distribution of the MxA protein in the MDCK cells was confirmed; significant changes in the expression of the interferon-stimulated genes, such as OAS1, PKR (EIF2AK2), MDA5, RIG-I, were revealed. Our further research will be focused on assessing the developed exogenous mRNAs’ therapeutic potential against influenza A and B viruses, respiratory syncytial virus, and coronavirus SARS-CoV-2.
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Khanty and Mansi are small indigenous peoples of Western Siberia with the unique cultural, anthropological, and linguistic characteristics. The study of their gene pool will make it possible to reconstruct the genetic structure of the Ugric-speaking population, of which in modern times only Khanty and Mansi remain, along with Hungarians, in whose gene pool there are traces of medieval migration of the Ugric-speaking Magyars. The detailed characterization of the gene pool of Khanty and Mansi is important for reconstruction of Ugric populations and genetic history of the region. The study was aimed to assess representative samples of Khants (n = 83) and Mansi (n = 74) based on the standard panel of 60 SNP markers and the extended panel of 74 Y-chromosomal SNP markers by statistical and cartographic methods in the context of indigenous population of Urals and Western Siberia. The differences between the gene pools of Khanty and Mansi have been revealed based on both standard panel of Y chromosome haplogroups and branches of haplogroups N2 and N3a4. Most of the Khanty gene pool is evenly distributed between N2-Y3195 (26%), N2-VL67 (23%), and N3a4-Z1936 (23%). The “Western” branch N2-Y3195 predominates in the Mansi gene pool (69%). Mansi gravitate towards populations of the Urals-Volga region in the multidimensional genetic space. Based on the standard panel of Y haplogroups, Khanty are close to the populations of Western and South Siberia. However, the analysis of branches N3a4 has shown that Khanty are intermediate between the “Uralic” and “Siberian” clusters: when the ancestors of Khanty moved from the Ural region to the northeast, these acquired both genetic components. The gene geographic maps of 10 haplogroup N3a4 branches in the populations of Urals and Western Siberia reflect the dynamic changes of the gene pool that took place 4–2 kya.
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Pseudomonas aeruginosa, the opportunistic pathogen, occupies one of the leading places in the structure of pathogens causing nosocomial infections, which is due to high adaptive potential and the ability to quickly develop antimicrobial resistance. The study aimed to assess the influence of the P. aeruginosa adaptation to colistin on bacterial fitness. A total of nine isolates obtained during the experimental evolution of the P. aeruginosa strain (laboratory number 1202) under conditions of increasing colistin concentrations, the growth kinetics of which was compared to that of wild type strain, were included in the study; the whole genome sequencing of all isolates was performed, and the minimum inhibitory concentration of colistin was determined. Growth rate was estimated using the Varioskan LUX multimodal reader (Thermo Scientific, USA) throughout 18 h at 37 °С; optical density (OD) at λ = 600 nm was measured every 15 min. The maximum growth rate (GRmax, i.e. the maximum change in OD within 1h) and the time to reach 50% of the maximum OD reported when growing the wild type Ра_1202_0 strain (T_OD50%) were considered. Isolates of the clone carrying mutations of the genes phoQ, lptA, and prs showed low fitness values compared to wild type strains. For example, GRmax of the isolate Ра_1202_43 was 0.029 OD/h vs. 0.182 OD/h reported for the original isolate Ра_1202_0, and it reached OD50% 4.6 h later. The growth characteristics of the clone carrying mutations of lpxL and lptB, as well as the clone carrying mutant pmrB were generally comparable with the characteristics of the wild type strain. Thus, the genome modifications observed during the P. aeruginosa adaptation to colistin have an ambiguous effect on bacterial fitness.
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