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Alzheimer's disease (AD) is the most common cause of dementia. An early feature of the AD pathology is the dysregulation of intracellular Ca2+ signaling in neurons. In particular, increased Ca2+ release from endoplasmic reticulum-located Ca2+ channels, including inositol-1,4,5-trisphosphate type 1 receptors (IP3R1) and ryanodine receptors type 2 (RyR2), have been extensively reported. Known for its anti-apoptotic properties, Bcl-2 also has the ability to bind to and inhibit the Ca2+-flux properties of IP3Rs and RyRs. In this study, the hypothesis that the expression of Bcl-2 proteins can normalize dysregulated Ca2+ signaling in a mouse model of AD (5xFAD) and thereby prevent or slow the progression of AD was examined. Therefore, stereotactic injections of adeno-associated viral vectors expressing Bcl-2 proteins were performed in the CA1 region of the 5xFAD mouse hippocampus. In order to assess the importance of the association with IP3R1, the Bcl-2K17D mutant was also included in these experiments. This K17D mutation has been previously shown to decrease the association of Bcl-2 with IP3R1, thereby impairing its ability to inhibit IP3R1 while not affecting Bcl-2′s ability to inhibit RyRs. Here, we demonstrate that Bcl-2 protein expression leads to synaptoprotective and amyloid-protective effects in the 5xFAD animal model. Several of these neuroprotective features are also observed by Bcl-2K17D protein expression, suggesting that these effects are not associated with Bcl-2-mediated inhibition of IP3R1. Potential mechanisms for this Bcl-2 synaptoprotective action may be related to its ability to inhibit RyR2 activity as Bcl-2 and Bcl-2K17D are equally potent in inhibiting RyR2-mediated Ca2+ fluxes. This work indicates that Bcl-2-based strategies hold neuroprotective potential in AD models, though the underlying mechanisms requires further investigation.

Recently discovered microcolonial forms of Mycoplasma hominis (M. hominis) and their impact on human spermatogenesis are studied. The spermatozoa of 125 fertile men (sperm donors; from Reprobank [Reproductive Tissue Bank, Moscow, Russia]) and of 93 patients with fertility problems (from the Federal State Budgetary Institution “Research Centre for Medical Genetics [RCMG]”, Moscow, Russia) were used. Classical colonies of M. hominis and microcolonies were detected by molecular biological methods, culture of bacteria, and transmission electron microscopy. The unique structure of microcolonial cells, in which the cytoplasmic cylinder is surrounded by concentric electron-dense and electron-light layers with a periodicity of 12–14 nm, and the ability of microcolonial cells to attach to spermatozoa are shown. In patients with lower sperm quality, microcolonies of M. hominis were detected 2.5 times more frequently than classical colonies. The detection of microcolonies in the ejaculate and the frequent isolation of microcolonies from sperm samples of patients with fertility problems suggest that microcolonial cells may be one cause of infertility.

The uncontrolled course of bronchial asthma (BA) in children and insufficient efficacy of standard therapy regimens may be due to underestimated infectious factors. The objective: to study specific parameters of the course and treatment of mycoplasma infection, improve monitoring over BA therapy in children of the tender and preschool age. Subjects and methods. 320 children with BA in the age from 1 to 7 years old were followed up. In this work, Mycoplasma pneumoniae (FH), Mycoplasma hominis (H-34), Ureaplasma urealyticum (serotype 8), Mycoplasma fermentans (PG18) and Mycoplasma arthritidis (PG6) were used, they were cultured on a liquid medium for cultivation of mycoplasmas and ureaplasmas. To isolate CIC from blood serum samples, we used the method of precipitation with 3.5% polyethylene glycol (PEG, 6000 Da), hemagglutination assays and IFA were used to identify mycoplasma antigens, mycoplasma DNA was detected by PCR with InterLabService diagnostic kits. The data of 47 patients with prolonged mycoplasma antigenemia were assessed at the baseline and in 1.5-3 months after the treatment course of azithromycin.Results. 320 blood serum samples from children with BA were tested, and the detection rate by hemagglutination assays of M. pneumoniae antigens was 60.9%, M. hominis – 43.4%, U. urealyticum – 44.8%, M. arthritidis – 29.7%, M. fermentrans – 45.3%. The assessment of relationship between of M. pneumoniae, M. hominis and asthma exacerbation showed that antigens of M. pneumoniae and M. hominis were found in 216 children (single or associated). After treatment with azithromycin, the frequency of BA exacerbations within 3 months decreased by 2.4 times, as well as there was a reduction in the number of samples positive for antigens and DNA of mycoplasma in a free state and within CIC. The persistence of antigens, DNA of M. pneumoniae and M. hominis before treatment of 47 children was 80.9 and 66.0% of cases, after treatment with azithromycin – 31.9 and 25.5% of cases, respectively (p < 0.001). Within CIC isolated from the blood serum of patients, antigens to M. pneumoniae and M. hominis before treatment were detected by IFA in 63.8 and 70.2% of children, after treatment – in 31.9 and 23.4%, respectively. p < 0.001. In blood samples, DNA of M. pneumoniae and M. hominis was detected by PCR before treatment in 8.5 and 34.0%; after treatment in 6.4% (p = 0.318) and 19.1% of cases, respectively (p = 0.009), and within CIC isolated from blood serum, in 27.7 and 48.9% of cases before treatment and 8.5 and 34.0% after it, respectively (p = 0.009).

Hydroxychloroquine (HCH) is included in guidelines for treatment of novel coronavirus infection (COVID-19). Data on increased risk of cardiovascular complications when using it have been published. Aim. To evaluate the safety and tolerability of HCH and azithromycine (AZM) combination for the treatment of the patients with COVID-19 in recommended by Russian Ministry of Health doses in real practice.Methods. 132 patients (62 men and 70 women of average age 59.2 ± 9.3 years), 59% of whom had cardiovascular comorbidities, were included in prospective сohort study. 112 patients took HCH + AZM (group 1) and 20 patients took other medications without potential cardiotoxicity (group 2). At the admission to the hospital and after 5–7 days of the treatment corrected QT interval was calculated, new rhythm and conduction disorders, other side effects and hospital mortality have been registering. Relative risk (RR) and 95% confidence interval (CI) were calculated. Results. Elongation of corrected QT-interval within the normal range was registered in 22.3% of patients in group 1 and in 15% — in group 2. An increase in the QT length to the upper limit of the norm (480 msec) was observed in 1.8% of patients in group 1. There were no statistically significant differences between the groups in the number of patients with prolonged QT interval (RR = 1.488, 95% CI: 0.496–4.466, р = 0.478). The occurrence of new arrhythmias, conduction disturbances and allergic reactions was not recorded. Tolerability of combination HCH + AZM was satisfactory in the majority of patients. The hospital mortality in group 1 was 1.8%, in group 2 — 5% without statistically significant difference (p = 0.374). Conclusion. A combination of HCL + AZM according to the scheme recommended by the Ministry of Health of the Russian Federation for the treatment of the patients with COVID-19 and cardiovascular comorbidity in inpatient conditions is safe.

A concentrate of the fermentation broth of Trichoderma harzianum Rifai F-180, an organism producing L-lysine-α-oxidase, an antitumor and antiviral enzyme, with the activity in the fermentation broth of 0.54-0.56 U/ml was recovered. The effect of the concentrate on the mycoplasmas growth was investigated for the first time. Two representatives of Mycoplasmafaceae, i.e. Mycoplasma hominis and Mycoplasma fermentans and one representative of Aholeplasmataceae. i. e. Aholeplasma laidlawii were used. It was shown that the fermentation broth inhibited the growth of Mycoplasma hominis after the preliminary exposure. The inhibition rate depended on the mycoplasma inoculation dose and the fermentation broth concentration.

Background. Guar or clusterbean (Cyamopsis tetragonoloba (L.) Taub.) is an annual leguminous plant cultivated for feed, food and industrial purposes. Its seed endosperm is used to extract guar gum, so the guar genetic resources stored in the VIR collection are of strategic importance for the import substitution policy in Russia in the context of their prospective introduction into cultivation in the country’s southern areas. Most of the guar accessions had been preserved by VIR for 40 years or more, so the task was to assess their germination rates and restore their viability. In the process of screening, seed quality parameters of the accessions were examined and analyzed.Materials and methods. VIR’s collection of C. tetragonoloba, initiated by N. I. Vavilov, now contains 111 accessions. Percentage seed viability, germination energy and seed hardness were evaluated in the Long-Term Storage Laboratory for 50 accessions reproduced in 2018 and for 263 older reproductions of 89 guar accessions. In total, 313 seed samples reproduced across 18 different years were analyzed. Statistica 10 software was used to perform a single-factor analysis of variance and find out how germination energy, seed viability and seed hardness correlated with the age of seeds, mean monthly temperature and mean rainfall during the growing season.Results and discussion. After more than 40 years of storage, the guar accessions did not entirely lost their viability under laboratory and field conditions. Very high positive correlations were found for their percentage viability and germination energy with the mean monthly temperature in the year of reproduction. A weak positive correlation was observed between seed hardness and the year of reproduction. Correlations between seed viability and rainfall during the growing season were weak, with a weak negative correlation between seed hardness and rainfall. The viability level of 30-year-old seeds was 50%, so guar may be regarded as belonging to the group of macrobiotic plants.

Mycoplasma hominis is an opportunistic bacterium that can cause acute and chronic infections of the urogenital tract. This bacterium, like all other Mycoplasma species, is characterized by the reduced genome size, and, consequently, reduction of the main metabolic pathways. M. hominis cells cannot effectively use glucose as a carbon and energy source. Therefore, the main pathway of energy metabolism is the arginine dihydrolase pathway. However, several bacteria can use nucleosides as the sole energy source. Biochemical studies using Salmonella typhimurium have shown that three enzymes (thymidine phosphorylase, phosphopentose mutase and deoxyribose-phosphate aldolase) are involved in the thymidine catabolic pathway. All these enzymes are present in M. hominis. For understanding changes in the energy metabolism of M. hominis we performed shotgun proteome analysis of M. hominis cells in liquid medium with arginine or thymidine as a carbon source. LC-MS analysis was performed with an Ultimate 3000 Nano LC System (Thermo Fisher Scientific) coupled to a Q Exactive HF benchtop Orbitrap mass spectrometer (Thermo Fisher Scientific) via a nanoelectrospray source (Thermo Fisher Scientific). Data are available via ProteomeXchange with identifier PXD018714 (https://www.ebi.ac.uk/pride/archive/projects/PXD018714).

EB3 protein is expressed abundantly in the nervous system and transiently enters the dendritic spines at the tip of the growing microtubule, which leads to spine enlargement. Nevertheless, the role of dynamic microtubules, and particularly EB3 protein, in synapse function is still elusive. By manipulating the EB3 expression level, we have shown that this protein is required for a normal dendritogenesis. Nonetheless, EB3 overexpression also reduces hippocampal neurons dendritic branching and total dendritic length. This effect likely occurs due to the speeding neuronal development cycle from dendrite outgrowth to the step when dendritic spines are forming. Implementing direct morphometric characterization of dendritic spines, we showed that EB3 overexpression leads to a dramatic increase in the dendritic spine head area. EB3 knockout oppositely reduces spine head area and increases spine neck length and spine neck/spine length ratio. The same effect is observed in conditions of amyloid-beta toxicity, modeling Alzheimer`s disease. Neck elongation is supposed to be a common detrimental effect on the spine’s shape, which makes them biochemically and electrically less connected to the dendrite. EB3 also potentiates the formation of presynaptic protein Synapsin clusters and CaMKII-alpha preferential localization in spines rather than in dendrites of hippocampal neurons, while its downregulation has an opposite effect and reduces the size of presynaptic protein clusters Synapsin and PSD95. EB3′s role in spine development and maturation determines its neuroprotective effect. EB3 overexpression makes dendritic spines resilient to amyloid-beta toxicity, restores altered PSD95 clustering, and reduces CaMKII-alpha localization in spines observed in this pathological state.

The actual problem of development of creative abilities of students in the context of project and educational activity is considered. It is emphasized that the solution of the problem is reflected in the current legislation of the Russian Federation in the field of education. From the authors’ point of view, educational project is a didactic tool, student activities of cognitive, creative or game character, carrying out at a collective level and involving a common goal and a coordinated methodology. Based on the works of modern researchers, the levels of disclosure of creative abilities of students are determined, representing the degree of independence, mobility, adaptive resources of intelligence and other individual properties essential for the full development of the student. It is noted that the most productive vector of work for the disclosure of students’ creative potential is the formation of a system of psychological and pedagogical factors that allow the student to take a firm individual position in overcoming the difficulties that occur in the context of design activities, and solve them in a creative way. Based on the study, the authors argue that the conditions have a positive impact on the improvement of mental, social, creative potential of the individual, lead to improved self-esteem, student’s understanding of independence, not only in the framework of design and educational activities, but also in future profession.

Recently discovered microcolonial forms of Mycoplasma hominis (M. hominis) and their impact on human spermatogenesis are studied. The spermatozoa of 125 fertile men (sperm donors; from Reprobank [Reproductive Tissue Bank, Moscow, Russia]) and of 93 patients with fertility problems (from the Federal State Budgetary Institution “Research Centre for Medical Genetics [RCMG]”, Moscow, Russia) were used. Classical colonies of M. hominis and microcolonies were detected by molecular biological methods, culture of bacteria, and transmission electron microscopy. The unique structure of microcolonial cells, in which the cytoplasmic cylinder is surrounded by concentric electron-dense and electron-light layers with a periodicity of 12–14 nm, and the ability of microcolonial cells to attach to spermatozoa are shown. In patients with lower sperm quality, microcolonies of M. hominis were detected 2.5 times more frequently than classical colonies. The detection of microcolonies in the ejaculate and the frequent isolation of microcolonies from sperm samples of patients with fertility problems suggest that microcolonial cells may be one cause of infertility. [ABSTRACT FROM AUTHOR]

Mycoplasma pneumoniae is a bacterial pathogen cause of upper and lower respiratory tract infections, transmitted by airborne droplets, causing outbreaks of pneumonia mainly in closed groups. According with recommendations, M. pneumoniae infections can usually be effectively treated with macrolides, which are generally considered the first-choice antibiotics in young adults. However, macrolide resistance has been observed in a number of countries. Macrolide resistance phenotypes are defined by specific point mutations in the V domain of the single-copy 23S rRNA gene of M. pneumoniae, mainly at positions 2063, 2064 and 2617 (numbering according to M. pneumoniae). Identification of appropriate single nucleotide substitutions allows effectively predicting the phenotype of resistance to macrolides, but the methods used for this purpose currently are laborious and costly. The present study is devoted to the development and validation of a new method for the determination of mutations associated with macrolide resistance in M. pneumoniae, as well as its use for the analysis of clinical specimens obtained from 31 patients with pneumonia treated in a military hospital. Two and one patients had M. pneumoniae isolates with a substitution at positions 2063 and 2064, respectively. In one case, a mixed population of wild-type and mutated M. pneumoniae isolate was observed. A rare mutation variant in the 23S rRNA gene of M. pneumoniae corresponding to the genotype C2617G was found in one patient. Our PCR-RT assay is able to discriminate between wild-type and resistant genotypes of M. pneumoniae directly from clinical specimens can be used to quickly identify type of mutations and predict possible resistance respiratory mycoplasmas to macrolide antibiotics. This assay will allow clinicians to shorten the time to the initiation of effective disease treatment.