卷 467, 编号 1 (2016)

The morphological and functional density of the retinal ganglion cells of the Baikal Lake endemic seal Pusa sibirica was studied using cresyl-violet-stained whole-mounts. An area of the highest concentration of ganglion cells has been identified by drawing up a density map. This was an ellipsoid spot in the upper temporal part of the retina 6–7 mm from the visual nerve output. The maximum cell density in this area was 3800 cells/mm². The retinal resolution estimated from the maximum density of ganglion cells and the posterior nodal distance (24 mm) was 2.4′ in the water and 3′ in the air, and this can be used as an estimation of the retina resolving power.

The first data on polymorphism and preadaptation of the Pleistocene horses in the mountains surrounding Lake Baikal are presented. It has been shown that disregard of intraspecific polymorphism leads to unreasonable ignoring of their diversity, phylogenetically false constructions, and incorrect interpretation of natural environment.

A nanostructured mineral food supplement with a particle size of 60.0–120.0 nm was manufactured from phosphorite by ultrasonic dispersion. It was found that intragastric administration of nanostructures phosphorite to mice is relatively safe: clinical signs of intoxication appeared after a single administration of the preparation only at a dose of 90 mg/kg; a dose of 150 mg/kg caused death of 8% of mice, in which injuries of organs of the gastrointestinal tract were observed. When the preparation was administered subcutaneously, intramuscularly, or intraperitoneally, small phosphorite conglomerates and inflammation of the surrounding tissues and organs were observed at the injection site. Death of 25% of animals was observed in the group of mice which received intraperitoneal injections of nanophosphorite at a dose of 200 mg/kg.

A new type of phoronid development, viviparity of larvae, has been discovered in a new phoronid species that lives as a commensal of digging sand shrimps in Vostok Bay, the Sea of Japan. The embryos develop in the mother’s trunk coelom up to the young larva stage. During development, embryos increase in size twice and probably obtain nutriment from the mother’s coelomic fluid. Spawning occurs by young larvae, which are released through nephridiopores. The new type of development is described in a phoronid that has a small body size but a high fertility, producing large amounts of extremely small eggs. The combination of viviparity and large number of eggs increases the number of competent larvae that can undergo metamorphosis in the burrows of shrimps.

Deformations of particular setae of adhesive toe pad of the tokay gecko were investigated by atomic-force microscopy. The effective elastic modulus of the investigated setae varying within 0.34–19 GPa, a pronounced hysteresis was observed during reversible bending of setae. The hysteresis-related energy losses may be as high as 98% of the total bending work. The pronounced viscous features of the setae contradict the hypothesis of dynamic self-cleaning of the gecko adhesive cover, according to which the setae are considered as absolutely elastic cantilever beams.

The paper presents the first morphological description of the internal organs of a frozen corpse of the steppe bison Bison priscus (Bojanus, 1827) from the Holocene of northern Yakutia. Necropsy revealed that most of the internal organs, including the brain, heart with the main vessels, and reproductive system were well preserved. It demonstrated that the anatomy of this bison was close to that of the genera Bos and Bison. Trauma or pathological changes in the organs were not detected. The cause of death of the bison remains unknown.

The cytokine-producing potential of blood cells has been studied in the atrophic gastritis–adenoma–adenocarcinoma progression of pathological states of the stomach. It has been revealed that, at the initial stage of carcinogenesis, namely adenoma, immunocompetent cells have the highest cytokine-producing proto-oncogenic potential as compared to both atrophic gastritis, which presents a precancerous condition, and completely formed malignant tumor (gastric adenocarcinoma).