The capacity of fusicoccin for inducing the synthesis of early interferon

The response of human and animal cells to the action of fusicoccin (FC), a fungal metabolite with phytohormonal properties, was evaluated. The capacity of FC for inducing the synthesis of early interferon (IFN), supplied into the blood serum of common white mice, and for enhancing the natural cytotoxic activity of human lymphocytes in vitro was established. The metabolism of actively proliferating monocytic leukemia cells J-96 and human ovarian carcinoma cells CaOv, as well as mouse fibroblasts L-929, was found to be inhibited under the in vitro action of FC. The common character of the mechanisms of action of FC and IFN having antiproliferative and immunomodulating activity is discussed.     

Lipid metabolism in rat tissues after irradiation at doses causing interphase cell death

Irradiation of animals with doses eliciting interphase death of 50-80% of cells activates lipogenesis and decreases the cholesterol content of cells. Cholesterol synthesis is activated after irradiation with doses causing death of 50% of cells: a further increase in radiation dose decreases the cholesterol synthesis. It is assumed that as membranes are destructed by radiation the adaptive lipogenesis activated to restore them.     

The role of A-cells in affecting the immunostimulating effect of F(ab')2-fragments

The immunoregulatory effect of F(ab')2 fragments on normal rabbit IgG and that preincubated with A-cells from spleen have been compared. Both products were tested for their ability to enhance primary immune response of rabbit spleen cells to SRBC. It was demonstrated that low molecular mass product appeared after F(ab')2 fragments incubation with A-cells at 37 degrees C and possessed immunostimulating activity similar to that of initial F(ab')2 fragments. In addition, it was shown that F(ab')2 reduction to monovalent Fab' fragment with the following alkylation of SH-group abolished the ability of Fab' fragment to enhance the immune response. It may signify that half cystein Fab' fragment residue is essential for processing of the fragment in A-cells and (or) for immune response enhancement.     

Landscape Agency and Evenki-Iakut Reindeer Husbandry Along the Zhuia River,Eastern Siberia

This interdisciplinary study applies a series of environmental tests developed in Fennoscandia to elaborate the patterns created by contemporary and past reindeer husbandry along the Zhuia River, Bodaibo district, Irkutsk oblast’, Russian Federation. We successfully used pollen and fungal spore analysis to document the long-term use of one site by ungulates–although it remains unclear if these animals were ‘domestic’ reindeer or not. The date of occupation could go as far back as the fourteenth century. The on-site phosphate analysis, attempted for the first time in Eastern Siberia, proved a useful tool for locating the sites of animal action although failed to specify the boundaries of that action. It did emphasise the importance of accounting for the agency of wind in ordering reindeer behaviour. Finally, the combined phosphate, botanical, and pollen work documented a history of succession of types of land-use from the hunting of Rangifer, to holding Rangifer, to the maintenance of meadows for horses or cattle, to the formation of cereal crops and vegetable patches. The combined use of these methods and a discussion of the ambiguities they produced suggests that they are best employed to find distinctive sites in the landscape which attract both people and animals and are less effective in documenting a Euro-American vision of trust or domination in human-animal relations.     

Simulation Study of Non-Organellar Binding of Calcium by Fast and Slow Buffers in Dendrites Containing an Organellar Store

Dependences of intracellular calcium signals on the concentrations of endogenous buffers (slow, parvalbumin, and fast, calmodulin) and a calcium-sensitive fluorophore (Fura-4F) were investigated on mathematical models of compartments of the reconstructed dendrite of a cerebellum Purkinje neuron. A Ca²⁺-storing cistern of the endoplasmic reticulum (ER) was present in the dendrite. Calcium signals developed when the neuron generated responses to single synaptic excitation or intrinsic non-periodical impulse activity. The dynamics of the buffer binding capacity were also studied; this capacity was characterized by the ratio of concentrations of bound and free calcium or concentration increments of the latter. The plasma membrane of the dendrite possessed ion channels (including those of synaptic currents) and the calcium pump characteristic of the mentioned neuron. Model equations took into account Ca²⁺ exchange between the cytosol, buffers, ER, and extracellular medium, as well as diffusion processes. The ER membrane contained the calcium pump, leakage channels, and channels of calcium-induced release and inositol-3-phosphate-dependent releases of Ca²⁺. The ER cistern occupied 1 to 36% of the intracellular volume. Upon different occupancies of the dendrite by the organelle store, an increase in the concentration of the slow buffer insignificantly decreased the cytosolic Ca²⁺ transients with no effect on their shape. The fast buffer and the dye with similar kinetic properties caused slowing down of the rising phase of Ca²⁺ transients, decrease in the early component, and increase in the late component of the latter. In the case of nonperiodical and asynchronous intrinsic oscillations of the membrane potential typical of asymmetrical active dendrites, the slow buffer, like the ER store, bound more Ca²⁺ in compartments of compatible sizes and fillings by the organelles belonging to those metrically asymmetrical branches, which, on average, stayed longer in the state of high depolarization; this provided a greater Ca²⁺ entry from outside. Hence, the pattern of structural/functional organization of calcium signalization in the dendrites can be complemented in the part of both the direct influences of local microgeometry of the dendrite and the indirect ones related to global macrogeometry of the dendritic arborization.     

AmylPepPred: Amyloidogenic Peptide Prediction tool

We present an efficient computational architecture designed using supervised machine learning model to predict amyloid fibril forming protein segments, named AmylPepPred. The proposed prediction model is based on bio-physio-chemical properties of primary sequences and auto-correlation function of their amino acid indices. AmylPepPred provides a user friendly web interface for the researchers to easily observe the fibril forming and non-fibril forming hexmers in a given protein sequence. We expect that this stratagem will be highly encouraging in discovering fibril forming regions in proteins thereby benefit in finding therapeutic agents that specifically aim these sequences for the inhibition and cure of amyloid illnesses.

Availability

AmylPepPred is available freely for academic use at www.zoommicro.in/amylpeppred     

A comparison of the dynamics of changes in large intestinal mucosa of acute dysentery patients with detection of a specific antigen in urine

The relationship between the elimination of shigellae from the body with urine and the dynamics of morphological changes in the mucous membrane of the large intestine of acute dysentery patients at the early convalescence period has been studied. The persistence of Shigella antigen in acute dysentery patients and its elimination with urine is, as a rule, accompanied by local immune cell reaction in the mucous membrane of the large intestine. The antigen circulating in the body is a factor contributing to the inflammatory process in the intestine, the amount of the eliminated antigen being higher in pronounced inflammations of the intestinal mucosa than in residual inflammatory phenomena. A group of patients (3 persons) releasing Shigella O-antigen with urine and having the inflammatory process in the large intestine, but showing no signs of local immune reaction in the lymphoid tissue of the large intestine, has been found. The reactivity of the lymphoid tissue of the intestine in such patients is a risk factor contributing to the development of prolonged dysentery or chronic postdysenteric colitis.