Molecular changes in the testes of COVID-19 patients.

After the sudden outbreak of the COVID-19 pandemic, scientists and clinicians around the world have significantly expanded understanding of the pathogenesis of the disease as well as the impact of SARS-CoV-2 on various organs and tissues. To date, it is accepted to consider the new coronavirus infection as a multisystem disease, but the data on the effect on fertility remains unclear. Previous works by other authors have presented controversial results, and there is no evidence of a direct effect of the new coronavirus on the male gonads. Thus, further studies are needed to verify the hypothesis that the testicles are the target organ for SARS-CoV-2. Groups were formed: Group I (n = 109; age from 25 to 75 years, Median (IQR) - 60 (23) years), cause of death - new coronavirus infection; Group II (n = 21, age from 25 to 75 years, Median (IQR) - 55 (29.5) years) - autopsy testicular material obtained outside the pandemic. We used RT-PCR to detect the presence of viral RNA in testicular tissue. In addition, we investigated the levels of proteins that provide viral invasion, such as ACE-2 and Furin. In the present study, we detected genetic material of a new coronavirus and increased proteins required for viral invasion in testicular tissue of patients with COVID-19 by RT-PCR. Thus, based on our findings, we assume that testicular tissue is potentially vulnerable to SARS-CoV-2.Communicated by Ramaswamy H. Sarma.

[Detection of SARS-CoV-2 RNA in the mucosa of the appendices of children with COVID-19]. / Vyyavlenie RNK SARS-CoV-2 v slizistoi obolochke cherveobraznogo otrostka u detei s COVID-19.

Background. The novel coronavirus infection (COVID-19) often manifests in children as diarrhea, vomiting, abdominal pain, and some children develop acute appendicitis. To elucidate the role of SARS-CoV-2 in the development of acute appendicitis, a more detailed study of the presence of its genetic material in the tissue of the appendix. OBJECTIVE: Determination of SARS-CoV-2 RNA in appendices of children with COVID-19 by fluorescence in situ hybridization (FISH). MATERIAL AND METHODS: A retrospective analysis of case histories and morphological analysis using FISH of appendices of pediatric patients with established clinical diagnosis of acute appendicitis and confirmed infection with SARS-CoV-2 was performed. The material was divided into 3 groups: 1st -appendices obtained during appendectomy in children with established clinical diagnosis of «coronavirus infection¼ (COVID-19, PCR+) (n=42; mean age 10.8 years); 2nd - appendices of children (n=55; mean age 9.7 years) with acute appendicitis obtained before the onset of the COVID-19 pandemic; 3rd (control) group (n=38; mean age 10.3 years) - autopsy material of the appendices (intact). RESULTS: In all samples of the appendices of the 1st group, a positive SARS-CoV-2 viral RNA signal was noted in the cytoplasm of most epithelial cells and single immunocompetent cells. The signal intensity remained the same in all slides, regardless of age. In all samples obtained from patients without COVID-19 (groups 2 and 3), confocal microscopy did not reveal a signal, which indicates successful adaptation of the FISH method in this study and excludes the false positive results. CONCLUSION: In the epithelium of the appendices of children of different age with COVID-19, the FISH method revealed SARS-CoV-2 RNA, which does not exclude the association between viral invasion and the development of acute appendicitis.

Application of lanthanum stearate monolayers as a metal-affinity sorbent for the selective sorption of soman adducts to human serum albumin.

A new metal-affinity sorbent based on lanthanum stearate monolayers has been developed and characterized. The prospect of its application to specific extraction of organophosphorous compound (OP) adducts of blood proteins was demonstrated. For this, the patterns of soman adducts of human serum albumin (HSA) were comprehensively characterized by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS).

[Cultured skin cells interaction with polylactide surface coated by different collagen structures].

The purpose of this work was an optimization of polylactide film surfaces designed for human keratinocytes cultivation. The polylactide films were coated by collagen 1. The experiments showed that uniform covering of polymer surface by collagen, and formation of different collagen structures depend on the mode of the protein application. The differences in collagen distribution on the polymer surface influened the keratinocytes growth in culture. Analysis of keratinocytes alignment, as well as cytoskeleton organization demonstrated that fibrillar collagen promoted more even keratinocytes distribution in comparison with the distribution on molecular collagen.

[Elaboration of biodegradable polymer substrate for cultivation of human dermal fibroblasts].

The influence of polylactic acid (PLA) surface films on the pattern of cell behavior was studied. The human dermal fibroblasts were cultivated on PLA covered glasses. The hydrophobic nature of PLA films depends on the availability of polymer solvent in the film preparation. PLA films obtained from a more polar solvent--aceton--appeared to be more hydrophilic than those obtained from methylene chloride. More hydrophilic polymer films also appeared to be more preferable for cell cultivation, and human dermal fibroblasts demonstrated a better adhesion and proliferation on hydrophilic rather than on hydrophobic PLA films.

Dynamic surface properties of poly(N-isopropylacrylamide) solutions.

The dynamic surface elasticity of aqueous solutions of poly(N-isopropylacrylamide) (pNIPAM) has been measured by the oscillating barrier and capillary wave methods as a function of time and concentration. While the real and imaginary parts of the surface elasticity almost did not change with the concentration, their kinetic dependencies proved to be nonmonotonic. Simultaneous measurements of the film thickness and adsorbed amount by null-ellipsometry showed that the pNIPAM adsorption can be divided into two steps corresponding to the formation of a concentrated narrow region close to the air phase and a region of tails and loops protruding into the bulk liquid. The local maximum of the elasticity can be observed in the course of the first step when the adsorbed macromolecules do not form long loops and tails. The results are in agreement with recent data on the nonequilibrium surface properties of solutions of other nonionic homopolymers and the theory of dilational surface viscoelasticity.

Dilational surface viscoelasticity of polymer solutions.

A review of recent results on the dilational surface viscoelastic properties of aqueous solutions of non-ionic polymers is given. In the frequency range from 0.001 up to 1000 Hz the methods of transverse and longitudinal surface waves and the oscillating barrier method were applied. Viscoelastic behavior of adsorbed polymer films significantly differs from the behavior of films formed by only conventional surfactants of low molecular weight. For example, the dynamic surface elasticity of the former systems is low and almost constant in a broad concentration range. One can observe the increase of the surface elasticity only at extremely low concentrations and/or in the range of semi-dilute solutions. If the surface stress relaxation in conventional surfactant solutions is usually determined by the diffusional exchange between the surface layer and the bulk phase, the relaxation processes in the polymer systems proceed mainly inside the surface layer. Possible mechanism of the latter relaxation is discussed.

The lawc gene is a new member of the trithorax-group that affects the function of the gypsy insulator of Drosophila.

Mutations in the lawc gene result in a pleiotropic phenotype that includes homeotic transformation of the arista into leg. lawc mutations enhance the phenotype of trx-G mutations and suppress the phenotype of Pc mutations. Mutations in lawc affect homeotic gene transcription, causing ectopic expression of Antennapedia in the eye-antenna imaginal disc. These results suggest that lawc is a new member of the trithorax family. The lawc gene behaves as an enhancer of position-effect variegation and interacts genetically with mod(mdg4), which is a component of the gypsy insulator. In addition, mutations in the lawc gene cause alterations in the punctated distribution of mod(mdg4) protein within the nucleus. These results suggest that the lawc protein is involved in regulating the higher-order organization of chromatin.