The zona pellucida (ZP) is a dynamically changing object that plays an important role during the preimplantation stage of embryogenesis. The ZP thickness may affect the implantation success and pregnancy rate, it is considered as a prognostic factor in a number of studies. The study was aimed to assess the dynamic changes in the mouse embryonic ZP thickness after laser assisted hatching (LAH) that involved breaching the ZP integrity at the blastocyst stage. Femtosecond laser pulses were used to perform the zona microsurgery. The zona thickness was measured both at the stage of blastocyst microsurgery (~Е3.5, i.e. 3.5 days of embryogenesis) and at the hatching stage (~Е5). Significant differences in the ZP thickness were revealed in the control group of embryos: from 6.21 µm (Е3.5) to 5.4 µm (Е5). The changes in thickness from 6.6 µm (Е3.5) to 6.2 µm (Е5) observed in the group subjected to LAH were non-significant. Tracing the ZP thickness of a particular embryo from the blastocyst stage to the hatching stage made it possible to estimate the thinning coefficients in the experimental and control groups. The findings that indicate lower tensile strength of the zona in case of LAH can provide the basis for further research on the ZP properties in case of using the embryo cryopreservation protocols.
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Anatomical features of the teeth should be accounted for dental treatment plans. The need for constant monitoring of changes in the dentition system determines the relevance of this research. The study aimed to establish the size of anterior teeth with the help of odontometry. We made bi-layer single stage impressions and cast diagnostic models of the anterior teeth of 50 male and 50 female participants aged 18–24 years. The absolute sizes of crowns of incisors and canines were established. To assess the reduction of lateral incisors, we calculated the interincisor index (Ii) of teeth 22 and 21; sexual dimorphism was determined using the Garn–Lewis formula. It was discovered that there are no differences in the mesiodistal widths of crowns of contralateral teeth on the right and left sides (p > 0.05). The mesiodistal width of crowns of anterior teeth decreases (significant changes) in the following order: maxillary central incisors → maxillary canines → mandibular canines and maxillary lateral incisors → mandibular lateral incisors → mandibular central incisors. The degree of reduction of lateral incisors is low (Ii = 74.9) and more prominent in males than in females. In the examined patients, the greatest mean length of crowns of anterior teeth is that of upper central incisors and lower canines, while upper canines are shorter in length and upper lateral incisors, lower central and lateral incisors have the shortest mean crown length. Males have longer (mean length) crowns of lower canines, upper incisors and canines than females, the difference being significant (p < 0.001). The parameters of the crowns determined in this study showed that they have sufficient height and mesiodistal width, which, together with the low degree of reduction of the lateral incisors, justifies the possibility of direct fabrication of orthodontic fixed retainers. The data can also be used at the stage of dental treatment planning.
VIEWS 95
The primary method of initial treatment of meningiomas is radical neurosurgical intervention. Various methods of intraoperative diagnostics currently in development aim to improve resection efficiency; we focus on methods based on molecular profiling using ambient ionization mass spectrometry. Such methods have been proven effective on various tumors, but the specifics of the molecular structure and the mechanical properties of meningiomas raise the question of applicability of protocols developed for other conditions for this particular task. The study aimed to compare the potential clinical use of three methods of ambient ionization in meningioma sample analysis: spray from tissue, inline cartridge extraction, and touch spherical sampler probe spray. To this end, lipid and metabolic profiles of meningioma tissues removed in the course of planned neurosurgical intervention have been analyzed. It is shown that in clinical practice, the lipid components of the molecular profile are best analyzed using the inline cartridge extraction method, distinguished by its ease of implementation and highest informational value. Analysis of oncometabolites with low molecular mass is optimally performed with the touch spherical sampler probe spray method, which scores high in both sensitivity and mass-spectrometric complex productivity.
VIEWS 111
The HaCaT cell line represents the spontaneously immortalized non-carcinogenic human keratinocytes that are used as a model for studying the function of normal human keratinocytes. There are two TP53 alleles in the HaCaT cell genome, which comprise two gain-of-function (GOF) mutations acquired through spontaneous immortalization (mutTP53). Mutations result in the increased proliferation rate and violation of the stratification program. The study was aimed to assess the effects of the mutTP53 gene knockout on the HaCaT keratinocytes capability of proliferation and migration in the in vitro model of epidermal injury and regeneration (scratch test), and on the ability to form stratified epithelium in the organotypic epidermal model. To perform the scratch-test, cells were cultured until monolayer was formed, then the standardized injury was created. The organotypic model was obtained by growing keratinocytes in the polycarbonate membrane inserts with the pore size of 0.4 μm at the interface between the phases (air-liquid). It has been shown that the mutant TP53 gene knockout results in the increased migration capability of the HaCaT keratinocytes: in the HaCaT with the mutTP53 knockout, the defect closure occurred faster than in the appropriate group of the WT HaCaT (p < 0.05), on day three the defect size was 12% ± 3% and 66% ± 5% of the initial size. There is evidence that mutant TP53 in the HaCaT cells is a negative regulator of the laminin 5 expression (LAMC2 expression was 9.96 ± 1.92 times higher in the cells with the mutTP53 knockout, p < 0.05), however, this does not promote normalization of the program of epithelial differentiation and stratification followed by formation of the stratum corneum in the organotypic model.
VIEWS 113
It has been proven that mRNA vaccines are highly effective against the COVID-19 outbreak, and low prevalence of side effects has been shown. However, there are still many gaps in our understanding of the biology and biosafety of nucleic acids as components of lipid nanoparticles (LNPs) most often used as a system for inctracellular delivery of mRNA-based vaccines. It is known that LNPs cause severe injection site inflammation, have broad biodistribution profiles, and are found in multiple tissues of the body, including the brain, after administration. The role of new medications with such pharmacokinetics in inflammation developing in inaccessible organs is poorly understood. The study was aimed to assess the effects of various doses of mRNA-LNP expressing the reporter protein (0, 5, 10, and 20 μg of mRNA encoding the firefly luciferase) on the expression of neuroinflammation markers (Tnfα, Il1β, Gfap, Aif1) in the prefrontal cortex and hypothalamus of laboratory animals 4, 8, and 30 h after the intramuscular injection of LNP nanoemulsion. It was shown that mRNA-LNP vaccines in a dose of 10–20 μg of mRNA could enhance Aif1 expression in the hypothalamus 8 h after vaccination, however, no such differences were observed after 30 h. It was found that the Gfap, l11β, Tnfα expression levels in the hypothalamus observed at different times in the experimental groups were different. According to the results, mRNA-LNPs administered by the parenteral route can stimulate temporary activation of microglia in certain time intervals in the dose-dependent and site specific manner.
VIEWS 110
Monocytes are large circulating white blood cells that are the main precursors of tissue macrophages as well as tumor-associated macrophages in the adult body. Different types of monocytes have multidirectional effects on the growth and metastatic spread of cancer cells, both activating and inhibiting these processes. Tumor progression is associated with the triggering of a whole cascade of inflammatory and immune reactions. These pathological processes are associated with changes in the amino acid content of monocytes, which can lead to disruption of their function, in particular their migration, division and maturation. The aim of the work was to profile the amino acids of monocytes, followed by a study of the amino acid composition of monocytes from patients with breast cancer using liquid chromatography with mass spectrometric detection. Significant differences in metabolite levels in monocytes of breast cancer patients and monocytes of healthy donors were found for glycine (p-value = 0.0127), asparagine (p-value = 0.0197), proline (p-value = 0.0159), methionine (p-value = 0.0357), tryptophan (p-value = 0.0028), tyrosine (p-value = 0.0127). In the study, we identified biological networks that could potentially be involved in altering the phenotype of monocytes affected by breast cancer (BC), using bioinformatic analysis of metabolic pathways involving the discovered amino acids. Mathematical models based on amino acid combinations with 100% sensitivity and specificity have been developed. Features of immune system cell metabolism in BC have been identified and potential diagnostic biomarkers have been proposed.
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