[Aging and clonal hematopoesis.]

The number of somatic mutations among all tissues increases along with age. This process was well-studied in hematopoietic stem cells (HSCs). Some mutations lead to a proliferative advantage and expansion of HSCs to form a dominant clone. Clonal hematopoiesis is general in the elderly population. Clonal hematopoiesis of indeterminate potential (CHIP) is a more common phenomenon in the elderly and is defined as somatic mutations in clonal blood cells without any other hematological malignancies. The development of CHIP is an independent risk factor for hematological malignancies, cardiovascular diseases, and reduced overall survival. CHIP is frequently associated with mutations in DNMT3A and TET2 genes involved in DNA methylation. The epigenetic human body clocks have been developed based on the age-related changes in methylation, making it possible to detect epigenetic aging. The combination of epigenetic aging and CHUP is associated with adverse health outcomes. Further research will reveal the significance of clonal hematopoiesis and CHIP in aging, acquiring various diseases, and determining the feasibility of influencing the mutagenic potential of clones.

[Non-transecting anastomotic urethroplasty for strictures of the bulbar urethra. Systematic review].

The results of using non-transecting anastomotic urethroplasty in men with bulbous urethral strictures are presented in the review. A total of 25 original publications were found, including 20 foreign and 5 Russian articles. The studies included from 1 to 358 patients who underwent anastomotic urethroplasty without transection of the corpus spongiosum (average number of patients in a study was 54). Etiological factors were indicated in 17 articles. Most studies (10 out of 17) indicated idiopathic etiology as the predominant one. There was no correlation between the results of the procedure and the etiology of urethral stricture. The mean length of urethral stricture in the vast majority of studies was less than 2 cm, and only in a few studies it was larger, with a maximum mean value of 3.9 cm. Postoperative complication rates were reported in 20 studies and ranged from 0% to 23.9% within one study (median 8.4%). In general, mild complications occurred, corresponding to category I-II according to the Clavien-Dindo classification. The incidence of erectile dysfunction was evaluated in 18 studies and ranged from 0% to 23% (average value of 6.5%). The success of non-transecting anastomotic urethroplasty averaged 94.7% (82-100%) with a median postoperative follow-up of 24.5 months (3-150 months). In 9 out of 25 studies, an additional comparison with transecting technique was done. In 6 studies, the superiority of the non-transecting technique in terms of treatment success and preservation of sexual function was found. The obtained results showed the high efficiency and safety of non-transecting anastomotic urethroplasty in case of short strictures of the bulbous urethra.

[Giant prostate stones: case report].

Small prostate stones are often found incidentally during clinical and radiological examination. Large stones, however, also may develop, replacing completely the prostate tissue and causing various symptoms. Such a large stones are commonly formed due to chronic urine reflux. There are 20 publications in the literature devoted to the patients with giant prostate stones. Open as well as endoscopic procedures can be performed. In our clinical case both approaches were done simultaneously. Such tactic was chosen in order to carry out a single-stage intervention, immediately solving two problems, i.e., urethral stricture and a giant prostate stone.

[Thioredoxin in fibroblasts of human dermis in the process of aging.]

The aim of this work was to examine the content of thioredoxin in fibroblasts of human dermis from the development until deep aging (from 20 weeks of pregnancy until 85 years old), and defining of a role of thioredoxin in age-dependent changes in the number of fibroblasts in the dermis. Thioredoxin, proliferating cells nuclear antigen (PCNA), marker of fibroblasts vimentin were detected with indirect immunohistochemical technique. Results showed that portion of fibroblasts with positive staining for thioredoxin in the dermis is increased from 20 weeks of pregnancy until 85 years old. Most expressed age related increase in portion of thioredoxin positive dermal fibroblasts (more than 9 times) is present form birth until 20 years as compared to antenatal period. General number and percent of PCNA positive fibroblasts in dermis are decreased with age with more expressed changes until 40 years old. Correlation analysis showed that age dependent decrease in the number of fibroblasts and their proliferative activity is significantly associated with increase in thioredoxin positive fibroblasts in dermis. Results allow to suggest that thioredoxin play a role in age dependent decrease in the number of fibroblasts and their proliferation in human dermis.

[Prospects of Genetically Encoded Flim Indicators for the Quantitative Assessment of Intracellular Parameters].

A significant number of genetically encoded indicators based on fluorescent proteins that allow detecting changes in various parameters: membrane potential shift, pH, concentrations of hydrogen peroxide, lactate, pyruvate, NAD+/NADH, ATP, calcium cations, etc. have been created. Some of them (for example, indicators of calcium cations and hydrogen peroxide) are successfully used by numerous groups of researchers in experiments in vivo. The fundamental limitation of most fluorescent indicators is their ability to only qualitatively assess the change in the parameter of interest in the cell. The nature of this limitation is that it is difficult to compare the absolute value of the measured parameter and the detected fluorescent signal for various reasons. Quantitative measurements impose an additional requirement on the indicator signal: it should not depend on the technical features of the experiment (such as the level of protein expression, the type and power of the excitation source, a set of fluorescent filters, etc.). The fulfillment of this requirement may be associated with the detection of the indicator signal in the time domain, where the main characteristic of the signal is the fluorescence lifetime. The fluorescence lifetime is an absolute value, insensitive to changes in the intensity of the excitation source, detection settings, losses in the optical path or sample, changes in the concentration of the fluorophore in the sample, photobleaching. Thus, when calibrating an indicator in the time domain, a specific value of the measured parameter is associated with a specific value of the fluorescence lifetime. The time-resolved imaging mode imposes its own limitations on the properties of the indicator's fluorescent core. Thus, the lifetime of its fluorescence should change in proportion to the value of the measured parameter, which is not characteristic of any fluorophore. In this work, we make a brief review of the principles of detection of the fluorescent signal of genetically encoded indicators, focusing on current approaches related to the analysis of time-resolved data.

[Perineal urethrostomy: results, clinical, statistical and terminological aspects].

The analysis of the results of perineal urethrostomy for urethral stricture in men for the period from 2000 to 2020 is presented in the article. We identified 29 original articles devoted to this technique, including 4 Russian and 25 foreign publications. In two studies, there were more than 100 patients, four studies included from 51 to 77 men, and in remaining studies less than 50 patients were analyzed. Complete data on all pre- and postoperative aspects of perineal urethrostomy were provided only in a few studies. In the overwhelm of cases, perineal urethrostomy was performed after one or several unsuccessful reconstructive procedures and only in few patients it was done prior to various types of urethroplasty. It was not possible to establish any association between etiological factors and localization of urethral stricture among these patients. The incidence of pan-urethral stricture ranged from 28.6% to 100%. Only in one study the average stricture length was 2 cm, while in all other studies it was 5 cm or more. Postoperative follow-up was on average 14 to 62 months. Treatment success with perineal urethrostomy ranged from 0% to 100%, but in most studies it was 75% or more. The most common perineal urethrostomy technique used included Blandy technique, and Johanson and 7-flap techniques.

[Iron deficiency anemia in elderly and senile patients.]

Anemic syndrome is common in 1/3 of the population, including iron deficiency anemia - in 1,5 billion people. Geriatric patients are one of the main risk group for anemia. Iron deficiency and iron deficiency anemia lead to a decrease in quality of life, an increase in morbidity and mortality, what requires timely diagnosis and treatment. The diagnostic algorithm includes the analysis of iron metabolism, inflammation markers and instrumental tests to verify the cause of anemia. Modern oral and parenteral iron preparations are used for treatment under control of blood indexes and iron metabolism parameters.

[Variability of Fragments of Nuclear Brca1 Gene, Exon 11, and Mitochondrial Cox1 Gene in House Mice Mus musculus].

To clarify genetic differences between subspecies of the house mouse Mus musculus, their distribution, and hybridization, we first conducted a comparative analysis of variability of nucleotide sequences of fragments of the nuclear gene Brca1, exon 11 (2331 bp), and mitochondrial gene Cox1 (1260 bp) in 40 house mice from West and East Europe, Transcaucasia, Siberia, and Central and South Asia. Brca1 genotypes were divided into five main groups, which differed in a number of fixed substitutions. Genotypes of each group are characteristic for the certain geographical region and the following subspecies: M. m. musculus, M. m. domesticus, M. m. castaneus, and M. m. wagneri together with M. m. gansuensis; a fifth group corresponds to an unidentified subspecies or a distinct genetic form of M. musculus from India (Sikkim State). Besides the homozygous specimens, we revealed mice, which were heterozygous for all diagnostic loci simultaneously; these specimens were determined as hybrid. Hybrid mice were mainly found in the zones of contact of subspecies, but in some cases, quite far from one of the parent subspecies (possibly, due to transportation). In two hybrid mice (from Bakhtiari Province of Iran and Transbaikalia of Russia), unique Brca1 haplotypes were detected. It cannot be ruled out that, at least partly, they may be characteristic of the M. m. bactrianus and M. m. gansuensis subspecies, respectively. Thus, the results of the study showed that the nuclear Brca1 gene is a promising molecular genetic marker for the analysis of variability, differentiation, and hybridization of house mice as well for subspecific identification of M. musculus specimens. Despite more rapid evolution of the Cox1 gene, it is not well suited for discrimination of M. m. musculus, M. m. wagneri, M. m. gansuensis specimens and Transcaucasian representatives of M. m. domesticus due to introgression and long-term maintenance of foreign mitochondrial DNA in populations. However, Cox1 gene analysis (along with the diagnostics of animals by nuclear DNA) may be useful for estimation of population differences in M. m. castaneus and M. m. domesticus subspecies.

Apoptotic Bodies of Cardiomyocytes and Fibroblasts - Regulators of Directed Differentiation of Heart Stem Cells.

We studied the effects of apoptotic bodies of cardiomyocytes (ApBc) and fibroblasts (ApBf) on myocardial regeneration and contractility in rats and the dynamics of RNA concentrations in cardiomyocytes and fibroblasts at different stages of apoptosis. ApBc increase the contractility of rat myocardium, while ApBf reduce it. ApBc stimulate the development of clones of cardiomyocyte precursors in the myocardium, while ApBf stimulate the formation of endothelial precursor clones. In doxorubicin cardiomyopathy, ApBc, similar to the reference drug (ACE inhibitor) improve animal survival, while ApBf produce no such effect. RNA concentrations in cardiomyocytes and fibroblasts before apoptosis and at the beginning of cell death significantly differed, while in apoptotic bodies of these cells, it was practically the same. It has been hypothesized that RNA complex present in ApBc and ApBf represents an "epigenetic code" of directed differentiation of cardiac stem cells.

[Oncological safety of nerve-sparing radical prostatectomy: evaluation of histopathological outcomes and recurrence-free survival].

OBJECTIVE: To evaluate histopathological outcomes and biochemical recurrence (BCR) free survival in patients after nerve-sparing radical prostatectomy (nsRP). MATERIALS AND METHODS: Prospective study group comprised 313 patients who underwent uni- or bilateral nsRP from 2014 to 2018; control group included 592 patients with clinically localized prostate cancer who underwent non-nsRP from 2014 to 2018. Mann-Whitney U-test was performed to assess continuous variables; chi-squared test was used for comparative analysis of categorical data. BCR free survival was evaluated with Kaplan-Meier method, log-rank test was used to compare survival outcomes. RESULTS: Adverse histopathological findings were lower in the study group: extracapsular extension was found in 9,4% and 18,75% (p<0,001), grade group upgrade in 23% and 29,3% (p=0,04), positive surgical margins (PSM) in 15% and 22,1% (p=0,01). Subanalysis according to cancer risk groups showed lower PSM rates in high-risk patients (15,6% and 30,3%, p=0,017) and tendency for higher PSM rates in low-risk patients in the study group with no significant difference (12,6% and 7%, p=0,16). BCR free survival after 12 months was 100% and 88,2%, after 20 months - 92,3% and 86,4%, p=0,04. PSM ratesin the study group were notsignificantly different depending on the type of surgery: 13,9% in robotic-assisted approach and 15,4% in retropubic approach, p=0,75. CONCLUSIONS: Relatively favorable histopathological outcomes and BCR free survival can be achieved after nsRP. However, obtained results could not be considered optimal and clearly indicate the need for further improvement of preoperative planning and intraoperative quality control of surgical treatment.

Sensors for Proteolytic Activity Visualization and Their Application in Animal Models of Human Diseases.

Various sensors designed for optical and photo(opto)acoustic imaging in living systems are becoming essential components of basic and applied biomedical research. Some of them including those developed for determining enzyme activity in vivo are becoming commercially available. These sensors can be used for various fluorescent signal detection methods: from whole body tomography to endoscopy with miniature cameras. Sensor molecules including enzyme-cleavable macromolecules carrying multiple quenched near-infrared fluorophores are able to deliver their payload in vivo and have long circulation time in bloodstream enabling detection of enzyme activity for extended periods of time at low doses of these sensors. In the future, more effective "activated" probes are expected to become available with optimized sensitivity to enzymatic activity, spectral characteristics suitable for intraoperative imaging of surgical field, biocompatibility and lack of immunogenicity and toxicity. New in vivo optical imaging methods such as the fluorescence lifetime and photo(opto)acoustic imaging will contribute to early diagnosis of human diseases. The use of sensors for in vivo optical imaging will include more extensive preclinical applications of experimental therapies. At the same time, the ongoing development and improvement of optical signal detectors as well as the availability of biologically inert and highly specific fluorescent probes will further contribute to the introduction of fluorescence imaging into the clinic.

[Non-transecting anastomotic urethroplasty].

The review analyzes the results of using non-transecting anastomotic urethroplasty in men with urethral strictures. Identified 14 original studies using this technique: 13 foreign and 1 Russian. In total, this technique was applied in 704 patients. This technique was used in 85% of cases with bulbar urethral stricture, in 15% - with posterior stricture.The average length of the urethral stricture in all studies was less than 2 cm, except for two works, where the average stricture length was 2.3 cm and 3.9 cm, respectively. This technique is equally successfully applied in all etiological variants of urethral stricture. The incidence of postoperative complications in all studies using non-transecting anastomotic urethroplastyaveraged 13.7%.Postoperative complications were mostly mild and corresponded to G1 according to Clavien-Dindo classification.According to 10 out of 14 studies that evaluated the effect of surgical treatment on the occurrence of erectile dysfunction (ED), the incidence of ED de novo was on average 13.4%. The success of treatment with the use of non-transecting anastomotic urethroplastyaveraged 95% (82-100%) with a median postoperative follow-up of 27 months (6-64 months). In 4 out of 14 studies, an additional comparison was transecting versus non-transecting techniques. Non-transecting technique was not inferior to transecting technique by any criterion, but, on the contrary, exceeded it in a number of indicators, including the dynamics of sexual function after surgery.On the basis of available studies on the use of non-transecting anastomotic urethroplasty, this technique should be recognized as a highly efficient and reasonably safe method for treating short urethral strictures and recommended for widespread clinical use.

Genetic Differentiation of the Steppe Field Mouse Sylvaemus witherbyi Populations: The Results of the Mitochondrial DNA Control Region Analysis.

The degree of genetic diversity of the steppe field mouse was estimated on the basis of the mtDNA control region variability data. Polymorphism of this mtDNA marker in S. witherbyi was more pronounced than previously assumed. The steppe field mouse population from the northern shore of Lake Manych-Gudilo includes several mitochondrial lines, which may be due to the existence of several migration flows to this area from Southwest Asia.

Taxonomic Interpretation of Allopatric Mammalian Forms on the Example of Two Karyoforms of Microtus (Terricola) subterraneus (Rodentia, Arvicolinae) from Eastern Europe.

New European pine vole records from the Novgorod, Kaluga, Voronezh, and Belgorod oblasts were studied by sequencing of the mtDNA cytb gene (1143 bp) and by karyotyping (routine staining and G-banding techniques). The results enabled us to summarize chromosome variability of this species throughout Eastern Europe. In the sample studied, two geographically replacing chromosomal forms have been identified: northern, 2n = 54 (Novgorod and Kaluga oblasts), and southern, 2n = 52 (Voronezh and, presumably, Belgorod oblasts). Our data make the boundaries of these two karyoforms in Eastern Europe more precise and testify to intraspecific level of their taxonomic differentiation.

[Characteristics of the Renin-Angiotensin-Aldosterone System in Carriers of Polymorphic Variants of the VDR Gene With Arterial Hypertension and Obesity].

AIM: to study the renin-angiotensin-aldosterone-system (RAAS) in patients with polymorphic variants of the vitamin D receptor gene (VDR), arterial hypertension (AH) and obesity. MATERIALS AND METHODS: We included in this study 98 patients with stage II-III AH and obesity (33 men, 65 women, mean age 61.1±9.9 years and BMI 43.3±5.0 kg/m2). The VDR gene study included genotypes TaqI, BsmI, FokI. After identification of TaqI, BsmI, FokI VDR gene sites we carried out measurements of levels of RAAS markers. RESULTS: We revealed an associative relationship between the presence of allele G of the BsmI site, C/C homozygosity of FokI site of VDR gene and presence of AH in patients with obesity. An increase of renin level was noted only in the homozygous T/T genotype of FokI, no differences in the concentration of aldosterone and angiotensin were detected between any of the studied genotypes. CONCLUSION: Polymorphic alleles and genotypes of the VDR gene can be used as predictors of AH development in obese patients with subsequent characterization of the state of the RAAS system.

[Diagnostic performance of 68GA-PSMA PET/CTin patients with prostate cancer].

INTRODUCTION: and aim. Most of the patients with biochemical recurrence after radical prostatectomy undergo salvage radiotherapy without guidance from imaging. In recent years, there has been an increasing role of Gallium-68 prostate specific membrane antigen (68Ga-PSMA) positron emission tomography/computed tomography (PET/CT) imaging in the management of prostate cancer. This study aimed to investigate diagnostic performance of 68Ga-PSMA PET/CT in patients with biochemical recurrence after radical prostatectomy. MATERIALS AND METHODS: From 2016 to 2017, 19 prostate cancer patients were evaluated by 68Ga-PSMA PET/CT at the Urology Clinic of S.P Botkin City Clinical Hospital; 17 of them had a biochemical recurrence and needed restaging of the disease. The age, prostate specific antigen (PSA) values, therapy at the time of the study, and maximum standard uptake value (SUVmax) were evaluated. RESULTS: The median age of patients was 65 years (interquartile range (IQR) 58.5-70.5), the median total PSA level was 2.36 ng/mL (IQR 1.5-4.19). In 8 of 17 patients, the PSA values did not exceed 2 ng/ml. The median time after radical prostatectomy was 33.2 months. (IQR 12-54.5). Positive PET/CT sites of recurrence were detected in 15 of 17 patients. Nine patients had only one positive site, and in six patients several positive sites were detected. Four patients with PET/CT positive pelvic lymph nodes and/or retroperitoneal space underwent salvage lymphadenectomy. Histological findings confirmed the presence of malignant growth in 3 out of 4 cases. CONCLUSION: 68Ga-PSMA PET/CT is an effective tool for the early detection of oligometastatic lesions in recurrent prostate cancer.

Nonactivated titanium-dioxide nanoparticles promote the growth of Chlamydia trachomatis and decrease the antimicrobial activity of silver nanoparticles.

AIMS: Chlamydia trachomatis and herpes simplex virus (HSV) are the most prevalent bacterial and viral sexually transmitted infections. Due to the chronic nature of their infections, they are able to interact with titanium-dioxide (TiO2 ) nanoparticles (NPs) applied as food additives or drug delivery vehicles. The aim of this study was to describe the interactions of these two prevalent pathogens with the TiO2 NPs. METHODS AND RESULTS: Chlamydia trachomatis and HSV-2 were treated with nonactivated TiO2 NPs, silver NPs and silver decorated TiO2 NPs before infection of HeLa and Vero cells. Their intracellular growth was monitored by quantitative PCR. Unexpectedly, the TiO2 NPs (100 µg ml-1 ) increased the growth of C. trachomatis by approximately fourfold, while the HSV-2 replication was not affected. Addition of TiO2 to silver NPs decreased their antimicrobial activity against C. trachomatis up to 27·92-fold. CONCLUSION: In summary, nonactivated TiO2 NPs could increase the replication of C. trachomatis and decrease the antimicrobial activity of silver NPs. SIGNIFICANCE AND IMPACT OF THE STUDY: The food industry or drug delivery use of TiO2 NPs could enhance the growth of certain intracellular pathogens and potentially worsen disease symptoms, a feature that should be further investigated.

The Ribosome as an Allosterically Regulated Molecular Machine.

The ribosome as a complex molecular machine undergoes significant conformational rearrangements during the synthesis of polypeptide chains of proteins. In this review, information obtained using various experimental methods on the internal consistency of such rearrangements is discussed. It is demonstrated that allosteric regulation involves all the main stages of the operation of the ribosome and connects functional elements remote by tens and even hundreds of angstroms. Data obtained using Förster resonance energy transfer (FRET) show that translocation is controlled in general by internal mechanisms of the ribosome, and not by the position of the ligands. Chemical probing data revealed the relationship of such remote sites as the decoding, peptidyl transferase, and GTPase centers of the ribosome. Nevertheless, despite the large amount of experimental data accumulated to date, many details and mechanisms of these phenomena are still not understood. Analysis of these data demonstrates that the development of new approaches is necessary for deciphering the mechanisms of allosteric regulation of the operation of the ribosome.

Structural Insight into Interaction between C20 Phenylalanyl Derivative of Tylosin and Ribosomal Tunnel.

Macrolides are clinically important antibiotics that inhibit protein biosynthesis on ribosomes by binding to ribosomal tunnel. Tylosin belongs to the group of 16-membered macrolides. It is a potent inhibitor of translation whose activity is largely due to reversible covalent binding of its aldehyde group with the base of A2062 in 23S ribosomal RNA. It is known that the conversion of the aldehyde group of tylosin to methyl or carbinol groups dramatically reduces its inhibitory activity. However, earlier we obtained several derivatives of tylosin having comparable activity in spite of the fact that the aldehyde group of tylosin in these compounds was substituted with an amino acid or a peptide residue. Details of the interaction of these compounds with the ribosome that underlies their high inhibitory activity were not known. In the present work, the structure of the complex of tylosin derivative containing in position 20 the residue of ethyl ester of 2-imino(oxy)acetylphenylalanine with the tunnel of the E. coli ribosome was identified by means of molecular dynamics simulations, which could explain high biological activity of this compound.

[Diet optimization in patients with obesity and diastolic heart failure based on the assessment of indicators of metabolism during physical exertion].

The objective of the work was to examine the performance of basal metabolism and body composition in obese patients with diastolic heart failure (DHF) to identify optimal needs of these patients in the nutrients and energy. We studied 222 patients with obesity, that were divided into four groups depending on the degree of obesity and the presence or absence of DHF with preserved systolic function of the left ventricle (2 groups of obese patients with an initial degree I-II, 2 groups - a pronounced degree of obesity III). Basal metabolism by indirect respiratory calorimetry, physical activity at home and cardiorespiratory exercise testing were evaluated in these groups of patients. It has been shown that patients with obesity and secondary DHF have significantly lower physical activity during the day, resulting in the reduction of the overall length of the active time of day to 18.5-26.9%, and in the decrease of the proportion of time performing heavy and moderate work to 27.6-80.3%. Anaerobic threshold in obese patients I-II degree was 62.9% of maximum oxygen consumption (VO2pik) (rate is more than 60%), in patients with obesity III degree - 77.6% of VO2pik. Alveolar gas exchange also was not broken - the CO2 ventilation equivalent was equal respectively 23.4±2.8 and 28.9±1.5 (rate is less than 32). Thus, cardiopulmonary exercise testing have demonstrated that cardiopulmonary causes of dyspnea in obese patients without DHF were absent; and the reason for the decrease of exercise tolerance in patients with obesity III degree was the detraining. The reason for inactivity in patients with obesity and DHF was a marked reduction in exercise capacity due to violations of alveolar ventilation and reducing aerobic capacity of muscles. It was found that accustomed physical activity of patients at home didn't allow patients with obesity and DHF to carry out effective fat oxidation, due to the rapid achievement of the anaerobic threshold. It has been suggested that this effect may be the cause of metabolic progression of obesity in patients with DHF. It was found that patients with obesity and secondary DHF were characterized by a more pronounced oxidation of the protein, compared with similar patients without DHF, which made actual the muscle mass patronage under diet therapy management of patients. The optimum performance of the chemical composition and energy value of the diet have been calculated for patients with obesity of varying severity in conjunction with SDS.