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The quantitative and qualitative adjectives of erythrocytes were studied in 25 athletes of triathlon and biathlon during long physical loads. The activity of G-6-PDG and GR in erythrocytes was studied. The amount and morphological form of erythrocytes changes during adaptation to significant physical loadings. The activities of G-6-PDG and GR reduced. The quantity of G-SH decreased. These shifts were less expressed at good adaptation and it is possible to use them as criterion of a degree of a high class athletes adaptation.

Congenital hearing loss can be caused by genetic abnormalities leading to inner ear malformations (IEM). SLC26A4 (pendrin) is an anion exchanger expressed in the inner ear, thyroid and β-intercalated cells in the kidney. Mutations in SLC26A4 cause a common form of IEMS: enlarged vestibular aqueduct (EVA), often accompanied by incomplete partition type 2 (EVA/IP2). However, only 25% of patients have confirmed mutations in SLC26A4. It has been reported that a group of polymorphisms upstream of the SLC26A4 gene, the CEVA haplotype, is frequently found in patients with monoallelic SLC26A4 mutations. Since the publication of the zebrafish genome in 2001, the zebrafish has become an increasingly popular animal model for studying human diseases. The transparency of the larvae, the large number of offspring and the accessibility of various methods of genetic, chemical and physical manipulation make it a very useful model for studying inner ear development. During early development, the inner ear undergoes dynamic changes from an otic placode and otic vesicle to a labyrinth of semicircular canals. Since data on the expression of genes associated with hearing are incomplete, we present here a detailed account of expression during early development. Secondly, we plan to create a zebrafish model for human SLC26A4 gene expression by introducing human upstream regulatory elements into the zebrafish genome. [ABSTRACT FROM AUTHOR]

TBC1D24 genetic variants are causally involved in the development of both autosomal recessive hearing loss and epilepsy syndromes, and autosomal dominant hearing loss (ADHL). So far, our group published four novel ADHL-causative TBC1D24 probably pathogenic variants by performing high-throughput genetic testing in families with ADHL, and more variants are yet to be revealed. In the light of current discoveries, variants in TBC1D24 emerge as a more significant cause of ADHL. The molecular mechanism behind the TBC1D24-associated ADHL is unknown. Using a zebrafish model, we investigated involvement of TBC1D24 in hearing and the functional effects of the associated ADHL-causing genetic variants. Different methodological approaches were used in the study, including (i) expression studies by whole mount in situ hybridization (WISH), qPCR on different developmental stages and cryosections, (ii) assessment of the zebrafish ear and neuromast hair cell morphology by high-resolution imaging and (iii) behavioral studies in a developed tbc1d24-deficient zebrafish models (by knock-down or knock-out of tbc1d24) and in overexpression and rescue tbc1d24 models. We show that the morpholino-mediated knockdown of Tbc1d24 resulted in defective ear kinocilia structure and reduced locomotor activity of the embryos. The observed phe-notypes were rescued by a wild-type TBC1D24 mRNA but not by a mutant mRNA carrying the ADHL-causing variant c.553G>A (p.Asp185Asn), supporting its pathogenic potential. CRISPR-Cas9-mediated knockout of tbc1d24 led to mechanosensory deficiency of lateral line neuromasts. Overexpression of TBC1D24 mRNA resulted in developmental abnormalities associated with ciliary dysfunction and mesen-dodermal mispatterning. We observed that the ADHL-causing TBC1D24 variants: c.553G>A (p.Asp185Asn); c.1460A>T (p.His487Leu), c.1461C>G (p.His487Gln) or a novel variant c.905T>G (p.Leu302Arg) alleviated the effect of overexpression, indicating that these variants disrupt the TBC1D24 function. Furthermore, the zebrafish phenotypes correspond to the severity of ADHL. Specific changes in ear structures upon TBC1D24 overexpression further highlighted its tissue-specific role in ciliary function and inner ear development. Our findings provide functional evidence for the pathogenic potential of the ADHL-causing TBC1D24 variants and lead to new insights into the function of TBC1D24 in cilia morphogenesis. [ABSTRACT FROM AUTHOR]

Induction of ventral neural cell types into differentiation is brought about by a vertebrate homolog of hedgehog, vhh-1, expressed in midline structures. Ecotopic expression of floor plate markers in the neural tube results from extensive expression of rat vhh-1 gene in frog embryos.

The problem of obtaining a low-temperature plasma jet, where the plasma-forming gas is a hydrogen-oxygen mixture produced by electrolysis-water generators, was considered. The aim of the work is to determine the size of the active zone of the jet, along the length of which the melting and heating of the particle takes place, and to control it by changing the nature of the flow. In the course of diagnosing the plasma jet, the distribution of temperature, velocity and effective thermal power depending on the nature of the jet flow was determined. It was determined that the sizes of the active zone of the plasma jet can be 1.4 times larger at a laminar nature of the flow than at a turbulent one. The maximum temperature is observed in the arc part of the plasmatron and amounts to 8400 ± 1000 K, in the jet of hydrogen-oxygen plasma the average temperature is 5000 ± 500 K. Taking into account the results of the diagnostics, the material for plasma spraying and distance can be chosen. 19 Ref., 1 Table, 2 Figures. [ABSTRACT FROM AUTHOR]

The combination of genomics with high-resolution bioimaging techniques to study animal development provides scientists with information regarding genes involved in regulation of development. As a result, the core of developmentally important transcription factors has been identified recently. Such approach was particularly fruitful for semitransparent zebrafish embryos. The use of zebrafish as a model system makes it possible to study developmental processes in vivo with a single cell resolution. [ABSTRACT FROM AUTHOR]