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Simple Summary Progesterone is an endogenous steroid hormone, which can induce capacitation and/or acrosome reactions in semen of certain mammalian species. Our study aimed to investigate the effect of progesterone on the functional status of fresh bovine spermatozoa using a chlortetracycline fluorescent probe. Results showed that heparin induced capacitation in spermatozoa incubated with or without progesterone. The destruction of microfilaments by an inhibitor of cytochalasin D blocked the stimulating effect of heparin. Steroid hormone in mixture with prolactin stimulated the acrosome reaction in spermatozoa, which was blocked by an inhibitor of microtubule polymerization (nocodazole). At the acrosome stage, prolactin provided the undergoing of acrosome reaction in male gametes. This effect was noted both in the presence and absence of progesterone and inhibited by nocodazole. The supplementation of dibutyryl cyclic adenosine monophosphate during the acrosome reaction to progesterone-untreated spermatozoa did not cause changes in proportion of acrosome-reacted cells. However, when progesterone was added during capacitation, a significant increase in the proportion of capacitated cells was noted, which was inhibited by nocodazole. Thus, progesterone under the action of prolactin and dibutyryl cyclic adenosine monophosphate determines the functional status of fresh spermatozoa, which indicates progesterone-modulating effect on the indicators of post-ejaculatory maturation of male gametes. Abstract The aim of this study is to identify the effects of progesterone (PRG) on the capacitation and the acrosome reaction in bovine spermatozoa. The fresh sperm samples were incubated with and without capacitation inductors (heparin, dibutyryl cyclic adenosine monophosphate (dbcAMP)), hormones (prolactin (PRL), PRG), inhibitors of microfilaments (cytochalasin D) and microtubules (nocodazole) during capacitation and acrosome reactions. The functional status of spermatozoa was examined using the chlortetracycline assay. Supplementation of heparin stimulated capacitation in the presence and absence of PRG. Cytochalasin D blocked the stimulating effect of heparin on capacitation. The addition of PRL during capacitation (without PRG) did not affect the functional status of spermatozoa, while in PRG-treated cells PRL stimulated the acrosome reaction. PRL (with and without PRG) increased the acrosome reaction in capacitated cells. These PRL-dependent effects were inhibited by nocodazole. During the acrosome reaction, in presence of dbcAMP, PRG decreased the proportion of acrosome-reacted cells compared to PRG-untreated cells. This effect in PRG-treated cells was canceled in the presence of nocodazole. In conclusion, PRG under the action of PRL and dbcAMP determines the changes in the functional status of native sperm cells, which indicates PRG modulating effect on the indicators of post-ejaculatory maturation of spermatozoa.

Spermatogonia are early-undifferentiated germ cells, giving rise to mature male generative cells — the spermatozoa. There are two types of spermatogonia – A and B. Of greatest interest is the use of type A spermatogonia, which are the stem cells of the testes. To select the appropriate age for collecting spermatogonia А from quails it is necessary to know the specific features of spermatogenesis. Development dynamics of various spermatogonia types in the quail testicular tubules was studied. Histological studies of the quails testicular tubules at the age of 1, 2, 3, 4, 5 and 6 weeks (n = 30) were carried out. Samples of testis tissue were fixed in Bouin’s fixative. Histological sections were stained with hematoxylin-eosin. Identification of different spermatogonia types was carried out according to their morphology. Type A spermatogonia were additionally identified by immunohistochemistry using SSEA-1 antibodies. The proportion of spermatogonia in the total number of spermatogenic cells in the seminiferous tubules of quails changed with age. The maximum value was reached at the age of 3 weeks and it was 76±6%. On reaching maturity (6 weeks), this indicator decreased to 12 ± 1 %. In the early period of ontogenesis (1–2 weeks), spermatogonia cells were represented mainly by type A spermatogonia. The proportion of these cells from the total number of spermatogonia reached 80 ± 3 %. With increasing age, this indicator decreased, reaching minimum values for achieving maturity (6 weeks) - 16 ± 1 %. The percentage of type B spermatogonia in the seminiferous tubule of quails on the contrary increased with age — from 5 ± 1% at 1 week old to 70 ± 2% at maturity. Thus, the age no later than 2 weeks is the most optimal for the isolation type A spermatogonia of quails. Supported by RFBR (18-29-07079).

The cells of the male gonads are considered as a valuable genetic material for the conservation of the gene pool of breeds and lines of agricultural birds, as well as the directed modification of the poultry genome. Mature germ cells – spermatozoa and their predecessors – spermatogonia, spermatocytes and spermatids can be used for these purposes. To obtain these types of cells, it is necessary to know the characteristics of their development (spermatogenesis). The dynamics of the development of certain spermatogenic cell types in the testicular tubules of different-aged roosters has been studied. Histological studies were performed on testes of roosters aged from 1 week to 6 months with an interval of 2 weeks. Samples of testis tissue were fixed in Bouin’s solution. Histological sections were stained with hematoxylin-eosin. Identification of different cell types (Sertoli, spermatogonia, spermatocytes, spermatids, sperm cells) was carried out according to their morphology. At the age of 1–6 weeks in the seminiferous tubule of roosters, the mainly presence of two cell types was noted: Sertoli cells and spermatogonia. From 7 weeks of age, spermatocytes were detected in the seminiferous tubules, in the 4 months - spermatids, in the 5.5 months - sperm cells. The number of Sertoli cells remained almost unchanged with age and was 21 ± 2. The percentage of these cells decreased with age from 71 ± 3 % to 5 ± 1 %. The percentage of spermatogonia also decreased with age from 75 ± 2 % to 7 ± 1 %. The number of spermatids and spermatozoa, on the contrary, increased to puberty (6 months) and reached 54 %. The study was supported by the RFBR within Project no.18-29-07079.

Cryopreservation of testicular stem cells - spermatogonia is of interest along with the creation of semen cryobanks. During transplantation into recipients’ testes, spermatogenic cells can create a significant population of germ cells in the process of differentiation. The knowledge about spermatogenesis course in males is necessary for the effective selection spermatogenic cells. The research aim was to study the age-related characteristics of spermatogenesis in geese. The histostructure of gander testes (n = 35) at the age of 1 to 7 months was studied. The diameter of seminiferous tubules, and the types and number of spermatogenic cells in them were evaluated. From each gander at least 30 seminiferous tubules were examined. At the age of 1 month, the diameter of the seminiferous tubules was 51±1 μm. In subsequent age periods, this indicator increased and amounted to 63±2, 65±3, 66±2, 79±3, 98±6 and 170±5 μm at the age of 2, 3, 4, 5, 6 and 7 months, respectively. Diameter increase with the age was associated with an increase of spermatogenic cells number inside tubules. At the 1 months age, the number of spermatogenic cells in one seminiferous tubule did not exceed 22±1. At the age of 2, 3, 4, 5, 6, and 7 months, this indicator increased by 2.1, 2.7, 3.1, 6.4, 8.5 and 21.2 times. At the age from 1 to 3 months, the main cells types were Sertoli and spermatogonia cells. Primary and secondary spermatocytes from 4 months of age and spermatids from 5 months of age were visualized in the seminiferous tubules. Sperm were detected in the seminiferous tubules at 6 months old, the number of which increased towards the age of 7 months. The study was supported by RSF within Project №16–16–04104.

The article deals with the field of artificial intelligence in two aspects: (1) in the broad sense, the interaction between man and machine, the automation of processes, intellectual automation are considered; (2) specifically it treats neural networks applications, in particular for the recognition of echolocation signals. The possibilities for underground coal mining without the permanent presence of workers in areas of working faces (the so-called technology of unmanned coal mining) are studied, in this respect advantages of plow cutter technology for thin seams being shown as well as needs of its perfection. Main objectives for automation of technological and logistical operations during underground coal excavation are analyzed; in particular, to achieve greater maneuverability of extraction units by controlling their positions on the bottoms of coal seams. The paper also notes that the main of controlling positions of machines that result from non-parallelism of the drifts, assume the use of technique of neural networks being proposed as the means of adjusting these positions. It is shown that the dynamism of the operation mode of the electric drive when mining thin seams demands application of tensioning devices for plow chain to reduce dynamic loads in the electromechanical system in question. As for the operation system of unmanned coal mining as a whole, intelligent control with the possibility of creating self-organizing systems is discussed and proposed.

The use of testicular stem cells (spermatogonia) is of most interest for obtaining individuals with predetermined traits and genome genetic modification and for conservation of poultry gene pool. A significant population of mature donor germ cells (sperm) is formed upon successful spermatogonia cells transplantation into the testes of male recipients. Obtained sperm can be used to produce offspring with the desired traits. A key step in this technology is the removal of own spermatogenic cells (inhibition of spermatogenesis) in male recipients. The aim of research was to develop and optimize methodological approaches to inhibit the spermatogenesis in quail using busulfan. This drug was injected directly into the testes parenchyma of mature males by multiple injection at the concentration from 20 to 100 mg per 1kg of body weight (n = 25). Histological preparations of testes from the experimental quails were obtained to study composition of spermatogenic cells in the seminiferous tubules after busulfan administration. The male peers who were not injected with busulfan were used as a control. Experimental quails showed a decrease in the number of spermatogenic cells in the seminiferous tubules 32, 75, 111, 119 and 118 times compared with the control when using busulfan in concentrations 20, 40, 60, 80 and 100 mg/kg of weight, respectively (P < 0.001). The cells composition in the seminiferous tubules from experimental quails was represented mainly by Sertoli cells and spermatogonia. After busulfan introduction at the concentrations 20, 40, 60, 80 and 100 mg/kg, the percentage of spermatogonia was 55±5 %, 24±4 %, 6±2 %, 5±2 % and 4±1 %, respectively. The use of busulfan at the concentration of 80–100 mg/kg led to high mortality of quails. Thus, it was found that the optimal busulfan concentration for elimination of quail spermatogenic cells was 60 mg/kg. Supported by RFBR within Project №18-29-07079.

Development of stress-resistant plant varieties is a main task of plant biotechnology which is gaining popularity nowadays following the climatic changes and increased environmental pollution. This task implementation is primarily depends on identification of new genes responsible for stress resistance and also on the analysis of all functional features of genes on a cellular, tissue and organ levels. This article is dedicated to the study of Arabidopsis thaliana mutant nfz24 and the analysis of theNFZ24 gene function in cold stress response. It was demonstrated that reduced carotinoid content and alteration in ABA dependent cold response are the reasons of nfz24 cold sensitivity.

The potentiality to increase the chemotherapeutic effectiveness of some cytostatics in low, subtherapeutic doses in combination with nitric oxide (NO) donor has been shown. This type of combined therapy results in significant increase in life span and number of survivors among mice bearing leukemias P388 and L-1210. A similar effect was observed for intracerebral leukemia P388 transplantation. In this case the life span of mice treated with cyclophosphamide and NO donor increased by three times in comparison to therapy with cyclophosphamide alone. The coinjection of nitric oxide donor and cytostatics improved the antimetastatic activity of the cytostatics: the index of melanoma B16 metastasis inhibition at the cyclophosphamide monotherapy is 50%; on addition of NO donor the index is over 80%. Comparative studies of NO donor (organic nitrate) and a similar compound in which ONO(2) moieties were replaced by OH groups demonstrated that the presence of NO(2) is required for adjuvant activity of compounds and confirmed that nitric oxide modifies the antitumor effects of cytostatics. It is shown also that nitric oxide donor retards the development of drug resistance to cyclophosphamide.

The platinum(iv) complexes cis,trans,cis-PtIV(RNH2)(NH3)(OH)2Cl2, where R is 2,2,6,6-tetramethyl-1-oxyl-4-piperidinyl (1) or 2,2,5,5-tetramethyl-1-oxyl-3-pyrrolidinyl (2), were prepared by oxidation of the corresponding cis-PtII(RNH2)(NH3)Cl2 complexes with hydrogen peroxide. The reactions are catalyzed by tungstate salts, which makes it possible to carry out oxidation under mild conditions. The resulting complexes were characterized by elemental analysis, HPLC, and IR, UV, and ESR spectroscopy. The structure of complex 1 was established by X-ray diffraction analysis. Complex 1 exhibits the highest antitumor activity in an experimental tumor, viz., in P388 leukemia. The resistance of the tumor to this complex developed much slower than that to Cisplatin.

Mixed-ligand platinum complexescis-PtII(R6NH2)(NH3)X2 andcis-PtII(R5NH2)(NH3)X2 (R6 is 2,2,6,6-tetramethyl-4-piperidyl-1-oxyl and R5 is 2,2,5,5-tetramethyl-3-pyrrolidinyl-1-oxyl) were synthesized by either the reaction of aminonitroxides RNH2 with Na[PtII(NH3)Cl2I] generatedin situ (for X2=ClI) or by replacement of the iodo-chloro ligands incis-Pt11(RNH2)(NH3)ClI by dichloro and oxalato ligands. The complexes obtained were characterized by elemental analysis and by IR, UV, and ESR spectra. Forcis-Pt11(R5NH2)(NH3)Cl2, crystal and molecular structures were determined by X-ray diffraction analysis. Cisplatin accelerates autooxidation of methyl linoleate and the platinum nitroxide complexes synthesized exhibit antioxidant properties. The rate of isolated DNA binding with the new complexes is almost as high as that for cisplatin.cis-Pt11(R6NH2)(NH3)Cl2 exhibits the highest antitumor activity. The high antitumor activity of platinum nitroxide complexes shows that the possible “radical component” is not a crucial factor in the cytotoxic action of cisplatin.

The platinum(iv) complexes cis,trans,cis-PtIV(RNH2)(NH3)(OH)2Cl2, where R is 2,2,6,6-tetramethyl-1-oxyl-4-piperidinyl (1) or 2,2,5,5-tetramethyl-1-oxyl-3-pyrrolidinyl (2), were prepared by oxidation of the corresponding cis-PtII(RNH2)(NH3)Cl2 complexes with hydrogen peroxide. The reactions are catalyzed by tungstate salts, which makes it possible to carry out oxidation under mild conditions. The resulting complexes were characterized by elemental analysis, HPLC, and IR, UV, and ESR spectroscopy. The structure of complex 1 was established by X-ray diffraction analysis. Complex 1 exhibits the highest antitumor activity in an experimental tumor, viz., in P388 leukemia. The resistance of the tumor to this complex developed much slower than that to Cisplatin.

Suspension cells of Dioscorea deltoidea Wall (strain D-1) were maintained in a semicontinuous culture (SCC) in shake flasks at a high growth rate. It was shown that continuous propagation growth of this culture is unstable on Murashige's and Skoog's (MS) medium due to P starvation. On a P-enriched MS-medium the SCC was stable even at mean specific growth rates >0.3 day(-1). Highest volumetric concentrations of furostanol glycosides were obtained, when a P-enriched SCC was not further subcultivated but fed with sucrose. The investigated culture is able to control phosphate uptake and to prevent toxicity on media with excess P. High concentrations of cellular P(i) did not effect the ratio of furostanol to starch.

We evaluated the activity of ruboxyl (Rbx), a nitroxyl analogue of daunorubicin (Dauno), in experimental models of hepatic metastases from colorectal carcinoma (CRC) and compared it with its parent compound and with 5-fluorouracil (5FU). In mice treated by intraperitoneal injections Rbx and 5FU proved more effective than Dauno: the Index of Inhibition of Metastases in comparison with controls was 43% for Dauno, 70% for 5FU and 84% for Rbx. In BDIX rats implanted with the syngeneic cell line DHD K12/TRb, both Rbx and 5FU, administered as a continuous intravenous infusion for 7 days, reduced the development of liver metastases from a median of 23.8 +/- 2.16 for controls to 3.2 +/- 1.3 for 5FU and 1.0 +/- 1.4 for Rbx (p0.0001 versus controls for both treatments): the comparison of Rbx and 5FU showed a trend in favour of this new anthracycline. Median survival was prolonged from 40.6 +/- 3.4 days in controls to 56.0 +/- 5.8 days with Rbx and 58.0 +/- 4.69 days with 5FU. Considering that in a phase I study Rbx showed only minor and manageable toxic side effect, its activity in the clinical treatment of CRC metastases may deserve further attention.

Platinum complexes PtII(DAPO)X2 with diaminonitroxyl radical-trans-3,4-diamino-2,2,6,6-tetramethylpiperidine-1-oxyl (DAPO)-were synthesized by the direct reaction of DAPO with K2PtX4 (X = Cl, I) or by the replacement of chloro ligands in PtII(DAPO)Cl2 by bromo, nitrato, oxalato, malonato, and 1,1-cyclobutanedicarboxylato ligands. The complexes thus obtained were characterized by elemental analysis, infrared,electronic, electron paramagnetic resonance spectroscopic techniques, and high-performance liquid chromatography. The toxicity of compounds in terms of LD50 strongly depends on the nature of X-ligands, and varies between 11 mg/kg (X = NO3) and 400 mg/kg (X2 = 1,1-cyclobutanedicarboxylate). Up to 66% of mice bearing leukemia L1210 survive after the administration of these complexes. This effect is comparable to the effect of cisplatin (50% survive). An increase in the life span of the rest of the animals ranges from 158 to 383%. Complex PtII(DAPO)Cl2 appears to be more efficient than cisplatin against adenocarcinoma 755. Cisplatin, cis-diamminedichloroplatinum(II); CBDCA, 1,1-cyclobutanedicarboxylic acid; DAPO, trans-3,4-diamino-2,2,6,6-tetramethylpiperidine-1-oxyl; Mal, malonic acid; Ox, oxalic acid; IR, infrared; EPR, electron paramagnetic resonance; HPLC, high-performance liquid chromatography; Ca755, adenocarcinoma 755; LD50 and LD100, dose of compounds (mg/kg), causing a death of 50 or 100% or treated animals; ILS, increase in life span of mice.

The hemolytic action of a homologous series of beta-D-glucopyranosyl-1-alkylphosphates on human erythrocytes has been examined. The agent's affinity for the red cell membrane and the mean number of the agent's molecules which, upon interaction with an erythrocyte, make it undergo hemolysis have been measured. The contribution of the head group and that of a CH2 group of the surfactants to the free energy of the agents' binding to the cell membrane have been estimated. The effect of the surfactants on the red cell volume and the lytic concentrations of the agents have been measured. The contribution of a CH2 group to the free energy of the interaction of the amphiphiles embedded in the membrane bilayer with their environment has been evaluated and is proposed to be used as a measure of the membrane matrix stability.

Transpeptidation reactions catalyzed by chymotrypsin, pepsin, leucine aminopeptidase and thermolysin have been studied in heavy oxygen water (H2 18O). The 18O incorporation into the peptide bond of transpeptidation products and into the non-hydrolyzed substrate has been measured. The rates of 18O exchange in the carboxylic groups of N-acetylphenylalanine and leucine, catalyzed by pepsin and leucine aminopeptidase, respectively, have also been determined. These rates have been compared with that of the exchange in the presence of amino compounds which reversibly form amide bonds with the above carboxyl-containing substances. The data obtained show that, in contrast to chymotrypsin, other enzymes studied do not form 'acyl-enzymes' but function by the mechanism of general-base catalysis. In other words, their catalytically active groups promote the abstraction of a proton from the water molecule, which attacks the susceptible bond of the substrate. The structure of intermediate compounds in this type of catalysis and the mechanism of the transpeptidation reaction are discussed.