High-resolution screening for marine prokaryotic and eukaryotic taxa with selective preference for PE and PET surfaces

Marine plastic debris serve as substrates for the colonization of a variety of prokaryote and eukaryote organisms. Of particular interest are the microorganisms that have adapted to thrive on plastic as they may contain genes, enzymes or pathways involved in the colonization or metabolism of plastics. We implemented DNA metabarcoding with nanopore MinION sequencing to compare the one-month-old biomes of hydrolysable (polyethylene terephthalate) and non-hydrolysable (polyethylene) plastics surfaces vs. those of glass and the surrounding water in a Mediterranean Sea marina. We sequenced longer 16S rRNA, 18S rRNA and ITS barcode loci for a more comprehensive taxonomic profiling of the bacterial, protist and fungal communities respectively. Long read sequencing enabled high-resolution mapping to genera and species. Using differential abundance screening we identified 32 bacteria and five eukaryotes, that were significantly differentially abundant on PE or PET compared to glass. This approach may be used in the future to characterize the plastisphere communities and to screen for microorganisms with a plastic-metabolism potential.

Avenues of research in dietary interventions to target tumor metabolism in osteosarcoma

Osteosarcoma (OS) is the most frequent primary bone cancer, affecting mostly children and adolescents. Although much progress has been made throughout the years towards treating primary OS, the 5-year survival rate for metastatic OS has remained at only 20% for the last 30 years. Therefore, more efficient treatments are needed. Recent studies have shown that tumor metabolism displays a unique behavior, and plays important roles in tumor growth and metastasis, making it an attractive potential target for novel therapies. While normal cells typically fuel the oxidative phosphorylation (OXPHOS) pathway with the products of glycolysis, cancer cells acquire a plastic metabolism, uncoupling these two pathways. This allows them to obtain building blocks for proliferation from glycolytic intermediates and ATP from OXPHOS. One way to target the metabolism of cancer cells is through dietary interventions. However, while some diets have shown anticancer effects against certain tumor types in preclinical studies, as of yet none have been tested to treat OS. Here we review the features of tumor metabolism, in general and about OS, and propose avenues of research in dietary intervention, discussing strategies that could potentially be effective to target OS metabolism.

Problems of animal husbandry intensification and ways to solve them

Integrated approach to the nutrition system allows you to reduce the negative effects of stress of various etiologies without а hypertrophied increase in productivity. The use of normotimic additives (lithium ascorbate) can increase the productivity of fattening pigs by 5–7 %, improve the quality of meat, and reduce the risks of obtaining low-quality meat products. The introduction of probiotics in the diet of pigs can increase the average daily growth by 5.4 %. The use of various antioxidants and antihypoxants leads to an increase in the average daily body weight gain of 13.3 %. Complex use of additives that increase stress resistance in animals can reduce losses associated with chronic stress in animals from 30 % to 5 %. Increasing stress resistance will allow you to level energy losses, normalize metabolism and increase plastic metabolism, which leads to an increase in the health of the animal and allows you to fully realize the genetic potential of the breed.

Ecologic-histophysiological overview of the involvement of the hypothalamo-hypophysial neurosecretory system in fish reproduction

The participation of the hypothalamo-hypophysial neurosecretory system (HHNS) in fish reproduction was shown by histomorphological and electronic microscopical studies with the use of quantitative morphometry. The activation of HHNS at the beginning of spawning and the following decrease of its functional activity was revealed in all studied one-time spawning fish species independently of the spawning season (based on spring-, autumn- and winter-spawning genera: Acipenser, Oncorhynchus, and Lota respectively). The diphasic reaction of HHNS corresponding to stages of “an alarm and resistance to stress”, is considered to be the reflection of its participation in protective-adaptive reactions of an organism to a physiological stress. In monocyclic species, right after spawning, there becomes the blockade of neurohormone releasing function from neurohypophysis corresponding to supernatural inhibition of system at disstress. At the beginning of spawning nonapeptide neurohormones (NpNh) of HHNS initiate spawning behavior and the appearance of “mating attire” by exposure to the central nervous system, pituitary gland and complex visceral organs. Then they promote ovulation and spermiation by stimulating the contraction of the smooth muscles of gonad. By the end of reproduction, they participate in the implementation of the body’s adaptations, aimed at overcoming physiological stress-spawning. Maintaining the body’s metabolic equilibrium is ensured by the pronounced anti-gonadotropic NpNh effect by inhibiting the gonadoliberin secretion and stimulating at the same time its antagonist – adrenocorticotropin secretion, as well as their direct effect on endocrine and generative gonad’s functions. This effect is crucial for the normalization of the physiological body state after spawning, as it allows to radically affect the nature of metabolic processes, by “switching” them from generative to plastic metabolism. A constructive working scheme of neuroendocrine regulation fish reproduction – its initiation (stimulating neurohormonal effect) and completion (inhibitory effect) by the self-regulation principle is presented. The important HHNS functional role in the integration of fish reproduction and the intended mechanisms for its participation in spawning migrations are discussed.

Experimental substantiation of the possibility of using the cytochemical parameters of peripheral blood to assess the functional state of the organism of the pilot

The activity of succinate (mitochondrial), lactate, α-glycerophosphate, glucose-6-phosphate peripheral blood lymphocytes in rats under the conditions of modeling acute and chronic gravitational stress was studied by quantitative spectrophotometry of cytochemical reaction products to reveal the localization of oxidative enzymes. The dynamics of morphofunctional transformations is determined, the severity of which depends on the duration of the effect (the rotation time of the animals on the centrifuge). For acute gravitational stress, changes in the activity of mitochondrial succinate dehydrogenase are characteristic, and in the various stages of chronic gravitational stress, glycolysis (increase in lactate dehydrogenase and α-glycerophosphate dehydrogenase activity) and plastic metabolism (increase in glucose-6-fosfata dehydrogenase activity) are characteristic. These changes are explained by the inclusion of neurohumoral regulatory mechanisms that ensure synchronization of oxidative metabolic processes in the cells of organs of various body systems under unfavorable conditions of their functioning. Significant correlation links between the activity of lymphocyte enzymes with the same indices of neurons of the celiac sympathetic node, adenocytes of the cortical and medulla of the adrenal glands have been established. This suggests that the activity of lymphocyte enzymes can be used as indirect indicators of the processes occurring in the organs of the sipato-adrenomedular and pituitary-adrenocortical systems under conditions of acute and chronic gravitational stress.

Histochemical research of cells functionally leading tissue liver and kidneys of rats after intravenous application of nanoparticles magnetite

After unitary and repeated intravenous application magnetite is shown their distribution in organism of a rat by method of magnetic resonance imaging. Accumulation of particles in a liver and a spleen of animals is shown. We studied intracellular activity main enzymes of hepatocyte and nephrocyte rats in various periods after intravenous application of nanoparticles magnetite by histochemical method. Intravenous application of magnetite is accompanied change of energetic and plastic metabolism of studied cells.

THE OTTAWA PLASTIC METABOLISM CAGE FOR SHEEP

A moulded fiberglass metabolism cage for sheep is described. In addition to conventional use, the cage is also suitable for metabolic studies involving trace minerals and radioisotopes and for collection of digesta from sheep equipped with re-entrant intestinal cannulas.