Doklady Biological Sciences最新文献

Expression of 11 genes of the Hox cluster (SiHox1, 2, 3, 5, 6, 7, 8, 9/10, 11/13a, 11/13b, and 11/13c) was assessed in the sea urchin Strongylocentrotus intermedius at early developmental stages, including the blastula (13 h post fertilization (hpf)), gastrula (35 hpf), prism (46 hpf), and pluteus (4 and 9 days post fertilization (dpf)) stages. Expression of SiHox7, 11/13b, and 11/13c was observed at the blastula stage; early activation of 11/13c was detected for the first time in regular sea urchins. The expression level was very low at the gastrula and prism stages. The pluteus stage showed a significant increase in expression of all Hox cluster genes. Deviations from temporal collinearity of Hox gene expression in echinoderms are discussed.

Spiny mice (Acomys cahirinus) exhibit the ability to regenerate the damaged myocardium and functional indices of the heart. demonstrated in various models of cardiac pathologies. Cardioregenerative potential of Acomys is associated with partial preservation of the neonatal phenotype of cardiac tissue in adult animals. The electrophysiology and mechanisms regulating the heart rhythm in Acomys are extremely poorly understood. The EEG was recorded in vivo and bioelectrical activity of the supraventricular myocardium was evaluated and mapped in spiny mice. Pacemaker-type action potentials were detected in a significant part of the right atrium, and primary activation involved approximately 41% of the atrium surface in Acomys. Cholinergic stimulation caused pronounced suppression of automaticity and changed the activation pattern of the pacemaker myocardium. IKAch-independent mechanisms mediated the cholinergic inhibition of automaticity in Acomys. Thus, the cardioregenerative potential of spiny mice manifests itself in delocalization and nonclassical regulation of the cardiac pacemaker.

Based on expeditions and experimental studies, energy characteristics underlying the interaction of energy exchange processes were assessed quantitatively in fishes of the Arctic. The linear and weight growth was studied for the first time in the nonmigratory species Arctic flounder Liopsetta glacialis (Pallas, 1776) of the Kara Sea. It was found that deceleration of biosynthetic processes leads to a relative decrease in the proportion of entropy generated by metabolic processes in cold-water marine fish species, while the growth becomes more efficient at low temperatures.

A histological comparison of lipofilling and hyaluronic acid filler injection was performed in rats. Studies at the histological level showed that, compared with hyaluronic acid filler injection, autologous fat grafting led to a more uniform distribution of adipose tissue at 30 days after treatment and a decrease in the area of sebaceous glands. Compared with lipofilling, the hyaluronic acid filler facilitated an increase in epidermis thickness because the granular layer and dermis grew thicker in addition to the filler injected into the subcutaneous space.

Most nudibranchs feed on hydroids and anemones and utilize kleptocnidae, which are stinging capsules stolen from eaten victims, for their own defense. The nudibranch Coryphella trophina (Bergh, 1890) was found to eat other nudibranchs. Stinging capsules that the predator uses for its defense have been stolen twice: first by mollusks feeding on cnidarians and then by C. trophina eating the mollusks.

Biodegradation of natural silk scaffolds made from gauze and satin fabrics was studied both in vitro and in vivo. Experiments were conducted using phosphate-buffered saline (PBS) and Fenton's reagent to model degradation. Samples demonstrated high stability in the model of physiological conditions and varying degradation rates in oxidative stress. In vivo studies in rats showed good biocompatibility of the scaffolds and a gradual reduction in inflammatory responses. The findings highlight the potential of silk scaffolds for use in various areas of regenerative medicine.

Fragments of the left tusk were studied in a Pleistocene walrus whose fossil remains were found on the bank of the Pechora River in 2009. The analyses covered granulometric, chemical, and normative-mineral composition of grounds surrounding the bones; thermal properties and chemical and trace element compositions of the tusk; X-ray diffraction parameters and chemical composition of bone bioapatite; macrostructure and elemental and amino acid compositions of bone organic matter; carbon and oxygen isotopic compositions of bioapatite; and carbon and nitrogen isotope compositions of bone collagen. Bioapatite showed moderately isotopically light carbon, which is characteristic of extracave fossil bones of Pleistocene animals, and isotopically heavy oxygen, which is typical of seawater bicarbonate. The isotopic data obtained for the organic matter of the Pechora walrus correlated with similar characteristics of marine animals, but suggest a fish diet rather than a mollusk diet, which is typical of modern walruses. The finding indicates that the habitat and diet of the Pechora walrus were unusual for marine predators.

Attenuated live Brucella strains are currently used in vaccines against brucellosis, causing serious side effects in animals and being hardly suitable for human vaccination. To develop a safer vaccine against brucellosis, plasmid DNA was constructed to express six Brucella proteins in mammalian cells. Linear polyethylenimine was used to increase the efficiency of DNA delivery into cells. Data on optimization of the conditions for the formation of DNA-polyethylenimine complexes were described. A single intramuscular or subcutaneous injection of plasmid DNA complexes with polyethylenimine at a low dose (20 μg/mouse) was shown to exert a reliable protective effect against subsequent challenge with a test Brucella strain.

The presence of pedicellate (subpedicellate) teeth with two calcification centers and a weakly mineralized dividing zone is described for archaic stem salamanders (Middle Jurassic-Early Cretaceous representatives of Karauridae). The presence of subpedicellate teeth, typical of the late larval stage of modern salamanders, confirms the neotenic nature of stem salamanders. The presence of pedicellate teeth in stem salamanders and stem caecilians confirms the hypothesis of pedicellarity as a synapomorphy of modern amphibian groups and, accordingly, the monophyly of Lissamphibia.

Poloxamer 188 (P188) was tested for effect on medullary hematopoiesis in aplastic anemia. P188 was administered to CBA mice with developing anemia via oral gavage at doses of 10, 100, and 500 mg/kg. A dose-dependent effect was observed, including an increase in erythrocyte count, hemoglobin, and reticulocyte count. The parameters remained low and suggested mild anemia on day 21 in a group treated with carboplatin. P188 was assumed to exert a beneficial effect on the blood cell composition, which is distorted by cytostatic drugs.