Translocation of Oligonucleotide–Oligosaccharide Complexes into Cells of the Brain

Irradiation of a mixture of oligonucleotides with dextran resulted in the formation of a complex that is detected by a decelerated migration of an irradiated sample in electrophoretic gel compared to a non-irradiated one. When injected into the brain of neonatal rats, the formed complex penetrated into the cells 3 times easier compared to the original oligonucleotide, thus indicating that the use of radiation crosslinking of oligonucleotides with oligosaccharides is promising to enhance the efficiency of delivery of gene-targeted oligonucleotide drugs into cells.     

The internal domain of hordeivirus movement protein TGB1 forms <Emphasis Type="Italic">in vitro</Emphasis> filamentous structures

The 63 kDa hordeivirus movement protein TGB1 of poa semilatent virus (the PSLV TGB1 protein) forms viral ribonucleoprotein for virus transport within a plant. It was found using the dynamic laser light scattering technique that the internal domain of TGB1 protein forms in vitro high molecular weight complexes. According to results of atomic force microscopy, a part of these complexes is represented by globules of different sizes, while another part consists of extended filamentous structures. Similar properties are also characteristic of the N-terminal half of the protein and are obviously due to its internal domain moiety. The data support the hypothesis that upon viral ribonucleoprotein complex formation, the N-terminal half of the PSLV TGB1 protein plays a structural role and exhibits the ability to form multimeric filamentous structures (the ability for self-assembly).     

The dynamics of thymalin localization in human thymus cells in embryogenesis

Immunofluorescence methods were applied to study the localization of the thymalin-containing cells in human thymic epithelium of 6-23-wk-old fetus and 2-3-yr-old infants. The study of the fetal thymus (6 weeks) showed the presence of thymalin in reticuloepithelial framework. These cells were present in both in the cortex (in subcapsular regions) and in the medulla; Thymalin-containing cells presence--in the Hassall's corpuscles (23 weeks). The same results were obtained with the infants thymus (3-yr-old).     

Salmonella typhimurium--test system for detecting the mutagenic activity of environmental pollutants. II. Mutagenic effect of heavy metal salts in an in vitro system with metabolic activation]

Mutagenic effect of zinc chloride on Salmonella typhimurium strain was detected using in vitro metabolic activation system. Cadmium chloride showed no significant mutagenic activity in the same system. It is recommended to use both in vitro and in vivo metabolic activation systems in mutagenicity testing of chemicals.     

Seasonal Changes in Body Mass and Activity of Digestive Enzymes in Eptesicus nilssonii (Mammalia: Chiroptera: Vespertilionidae) during Hibernation

Journal of Evolutionary Biochemistry and Physiology - Hibernation can be considered as a circannual cycle of feeding and fasting. During winter, the absence of dietary substrates in fat-storing...     

Genetic control systems of stem branching and plant height in linseed

A diallel analysis of the traits “plant height”, “number of lateral stems”, and “number of lateral shoots” was carried out using Hayman’s method in three self-pollinated lines and one linear cultivar of linseed. A similarity was demonstrated between the inheritance of the studied traits and the additive-dominant model without any nonallelic interactions. The recessive nature of inheritance of increased plant height and high numbers of shoots together with dominant inheritance of increased numbers of lateral stems was revealed. The number of blocks of polymeric genes responsible for the variability in the studied traits was also estimated. The lines of linseed were ranged according to their contents of dominant alleles.     

Analysis of Combined Action of Antagonists of Excitatory and Inhibitory Amino Acids on Motoneuron Postsynaptic Potentials of the Frog Rana ridibunda

The effect of blockers of excitatory and inhibitory amino acid receptors on postsynaptic potentials (PSP) evoked by activation of three synaptic inputs of the lumbar motoneuron (stimulation of the dorsal root, reticular formation, ventral and lateral columns) was studied on preparation of the isolated spinal cord of the frog Rana ridibunda. It has been shown that sensitivity of PSP to antagonists differs in different motoneurons, in the same motoneuron at activation of different inputs, and in the same input in different PSP components. It has been found that many descendent (DC) PSPs resistant to kynurenate or CNQX [1] were inhibited by blockers of inhibitory receptors. In this case the early component of DC-PSP varied considerably by amplitude and changed its polarity from positive to negative on the background of a low transmembrane depolarizing current. These changes were absent under conditions of replacement of chlorine ion by sulfate in the perfusion solution or treatment of the spinal cord with a blocker of inhibitory amino acids. All this allows suggesting that these DC-PSPs or their components were inhibitory. A part of PSPs resistant to kynurenate and CNQX were also resistant to the blockers of inhibitory amino acids (strychnine, picrotoxin, and bicuculline). In some cases, as a result of treatment with convulsants, the same blockers of excitatory receptors inhibited the initially resistant PSPs.     

Changes in the free-radical state and level of free iron during the formation of drug resistance in tumor cells

The development of resistance of K562 human erythroleukemia cells to doxorubicin, a widely used antitumor antibiotic with the prooxidant action, leads to changes in the free-radical state of cells. It has been found that the formation of superoxide anion in resistant cells decreases. The introduction of doxorubicin to the culture medium induced a considerably lesser increase in the formation of O2*- in resistant cells compared to sensitive cells. At the same time, a strong decrease in the ESR signal of semiquinone type with a g-factor of 2.006 was observed in a culture of resistant cells grown in the absence of doxorubicin as compared with sensitive cells grown under similar conditions. At the same time, a decrease in the level of paramagnetic nitrosyl complexes of nonheme iron in resistant cells was recorded, indicating a decrease in the content of free nonheme iron as a result of the formation of drug resistance. In addition, a decrease in the level of mRNA of the transferrin receptor in resistant cells was found by the RT-PCR. These data indicate the development of a coodinated redox-dependent adaptive response, which makes itself evident as a suppression of free radical processes during the formation of resistance of K562 cells to doxorubicin.