Estimation of the Parameters for Tremograms According to the Eskov–Zinchenko Effect

The features of the chaotic dynamics of parameters of the neuromuscular system (tremors) were studied using conventional and novel biological methods based on a multidimensional phase-space representation. The dynamics of involuntary micromovements of limbs (finger tremor) both in the relaxation phase (F = 0) and under static load (F = 3N) was manifested in a change in the number of “coincidences” of randomly selected sample pairs (k) of matrices (15 × 15) in paired comparison of tremograms, which demonstrated the global statistical instability of the samples (statistical distribution functions f(x), spectral densities of signals, and autocorrelation A(t)). The samples that result from one experiment cannot be randomly repeated in the next experiment (with the same homeostasis). This represents a quantitative measure of the Eskov–Zinchenko effect in the analysis of chaotically changing statistical distribution functions of tremogram samples. In this paper, the use of quasi-attractor parameters of tremograms (their areas) is proposed to represent changes in the neuromuscular system when passing from one homeostasis to another (G₁ ≠ G₂).

     

A Synthetic Fragment of the Receptor for Glycation End Products and Its Analogue Improve Memory in Transgenic Alzheimer’s Disease Mouse Model

Russian Journal of Bioorganic Chemistry - The membrane receptor for advanced glycation endproducts (RAGE) is involved in the development of a number of pathological conditions, including...     

A compartmental approach in modeling a neuronal network. Role of inhibitory and excitatory processes]

The conception and main principles of the compartmental approach to the modeling of neuronal networks are presented. Excitatory and inhibitory ties are described, and reducible and nonreducible neuronal networks are considered. The periodical solution in models of neuronal networks is the model of normal rhythmic (e.g., respiratory) activity. The role of external (chemoreceptor drives) is discussed. The biological interpretation of the results of modeling is given. The observed biological phenomena are considered.     

Reorganization of Composition of Striatal Neurons Correlating with Behavior in the Monkey Macaca nemestrina

The available experimental data do not provide a sufficiently complete picture of the neuronal activity connected with some action of the animal, as they have been obtained under different experimental protocols and as a result of study of different cells. The present work was aimed at studying activity of the same neuron group at different moments of animal's behavior. A monkey (Macaca nemestrina) was taught to perform a behavioral program consisting of several functional heterogeneous actions. The impulsive activity of striatal neurons was recorded in the central region of putamen with coordinates A 16.5, L7, and H 8–10 [18]. The activity of each neuron was recorded during 13 consecutive stages of the same behavioral task. As a whole, in 59 putamen neurons, 767 fragments of neuronal activity were studied. It was shown that the same neurons could be involved at different behavioral stages when the animal performed different actions. At individual stages, the number of neurons common with other behavioral stages reached 70–80% of all reactive cells at the stage. The number of the neurons common within the rest of 12 stages was determined for every program stage. The number of such common neurons established in the experiment was in 142 out of 156 cases higher than their number that could be expected on the basis of statistical relations. The data obtained indicate that the reorganization in composition of behavior-reactive cells at every behavioral stage occurs mainly by using the same neurons but not only the neurons that are specialized for the given action. The polymodality of individual striatal neurons is unlikely to be connected with that they have several functions, but results from that the same neuron can be a constituent of neuronal mosaics of different configurations corresponding to different behavioral moments.     

Antibodies to synthetic fragments of nucleophosmin for the specific detection of its monomeric and oligomeric forms

Immunoactive fragments corresponding to the N-terminal (19–36) and C-terminal (283–294) regions of the NPM1.1 isoform of nucleophosmin and their shortened fragments were chosen and synthesized. Rabbits were immunized with free full-size peptides and their protein conjugates. Antibodies produced against the 19–36 and 283–294 peptides were purified by affinity chromatography on cyan-bromide activated sepharose that was preliminary conjugated with the synthetic peptides. An analysis of immunoblots of lysates of the HeLa and Ramos cells demonstrated that the antibodies produced against the 19–36 peptide detected the monomeric form of nucleophosmin, whereas the antibodies against the 283–294 peptide predominantly revealed its oligomeric form. It was established by immunocytochemical analysis that the antibodies induced by the 19–36 peptide stained the nucleoplasm and perinuclear space of the cytoplasm of the HeLa and Ramos cells, but did not stain the nucleoli, while the antibodies against the 283–294 peptide stained only the nucleoli of the same cells. On the basis of these results, one could propose that the monomeric and oligomeric forms of nucleophosmin were located in the nucleoplasm and nucleoli of the examined cells, respectively. Thus, antibodies which can predominantly detect monomeric and oligomeric forms of nucleophosmin were produced for the first time. An analysis of the monomeric-oligomeric state and the localization of the nucleophosmin in tumor cells could be performed using these antibodies.     

Morphological and functional heterogeneity of rat ascitic hepatoma Zajdela cells

This work is devoted to the study of molecular and cellular mechanisms of disdifferentiation during neoplastic transformation of cells by investigating the malignant tumor cell heterogeneity. We have revealed two cell fractions of hepatoma Zajdela which differ in patterns of growth in primary culture. The cells of one fraction were attached to the culture plastic and grew in a monolayer (S-fraction), whereas cells of another fraction floated in the culture medium (F-fraction). Using method of lifetime supervision of primary culture cells (1-2 passages) at the limit of the resolving power of DIC-microscopy it has been revealed, that both fractions contain cells of several types. Some of them were specific for one of the fractions, and others were found in both fractions, but their frequencies differed. It has been shown by the same method, that long separate cultivation of these fractions in vitro (more than 50 passage) change both cellular structure and the initial ratio of different types of cells in both fractions. According to DNA flow cytometry, the cells of both fractions were hypotetraploid and had insignificant differences in DNA contents. After adaptation to in vitro conditions, S-fraction cells raised their proliferative activity in comparison with the F-fraction cells, and after long cultivation showed 2.3 times higher DNA content. Greater amount of cell surface laminin, a hepatocellular carcinoma marker, was observed on F-fraction cells than on S-fraction cells. Interfractional distinctions were confirmed also by immunologic assessment of hepatoma cells resistance to natural killer lyses: the sensitivity of S-fraction cells in primary culture was 2.4 times higher than F-fraction cells sensitivity, and, after long cultivation, F-fraction cells became practically resistant to cytotoxic action of natural killers. Based on the data obtained, the most probable paths of cell disdifferentiation during hepatoma Zajdela formation and during long cultivation of this tumor cells in vitro are discussed.     

Investigation of the Gelation of Galactomannan Isolated from the Seeds of Styphnolobium japonicum (Fabaceae)

Russian Journal of Bioorganic Chemistry - This article is devoted to the study of the structuring process of galactomannan isolated from Japanese Sophora seeds with borate ions. Based on...     

The diets of humpback whales (Megaptera novaeangliae) on the shelf and oceanic feeding grounds in the western North Pacific inferred from stable isotope analysis

Humpback whales feed on a variety of prey, but significant differences likely occur between regional feeding grounds. In this study, the diets of humpback whales were analyzed by comparing stable isotope ratios in animal tissues at three humpback whale feeding grounds in the Russian Far East: Karaginsky Gulf, Anadyr Gulf, and the Commander Islands. Anadyr Gulf is a neritic zone far from a shelf break, Karaginsky Gulf is a neritic zone close to a shelf break, and the Commander Islands represent an open oceanic ecosystem where whales feed off the shelf break. Samples from the Commander Islands had the lowest mean δ¹³C and δ¹⁵N values (mean ± SE: δ¹³C = ?18.7 ± 0.1, δ¹⁵N = 10.4 ± 0.1) compared to the samples from Karaginsky Gulf (δ¹³C = ?17.2 ± 0.1, δ¹⁵N = 12.7 ± 0.2) and Anadyr Gulf (δ¹³C= ?17.8 ± 0.1, δ¹⁵N = 14.0 ± 0.4). The samples from Anadyr Gulf had the highest δ¹⁵N values, while the samples from Karaginsky Gulf had the highest δ¹³C values. Both δ¹³C and δ¹⁵N values differed significantly among all three areas. Our data support the hypothesis that humpback whales tend to feed on fish in neritic areas and on plankton in deep oceanic waters.