Identification of Ca(2+)-activated Mg(2+)-dependent ATP-hydrolase activity of membrane microsomal fraction of loach embryo (Misgurnus fossilis L.)

The functional confirmation of availability of Ca2+ transport initially-active systems in the embryo cells of loach Misgurnus fossilis L. has been obtained. Using thapsigargin, the specific inhibitor of endoplasmic reticulum of Ca2+, Mg(2+)-ATPase, this enzyme activity was divided into thapsigargin-sensitive (actually endoplasmic reticulum Ca2+, Mg(2+)-ATPase) and thapsigargin-insensitive (plasma membrane Ca2+, Mg(2+)-ATPase) constituents. The Ca(2+)-independent Mg(2+)-dependent ATPase activity makes above 39.7% of the common Ca2+, Mg(2+)-ATPase activity of embryo loach. The periodic changes of Ca2+, Mg(2+)-ATPase activity (except for the changes of plasma membrane Ca2+, Mg(2+)-ATPase activity) were found out, which coincide with periodic [Ca2+]i oscillations during the synchronous divisions of loach blastomers embryos.     

Formation and dynamics of plasma layers formed on the foil surface under the action of a high-current pulse

Results are presented from studies of the possibility of using a thin metal foil for recyclable vacuum transmission lines with magnetic insulation in a conceptual fusion reactor based on high-voltage high-current electromagnetic generators. Numerical simulations and experiments in the Angara-5-1 facility were carried out to determine both the threshold for the explosion of a foil heated by a current pulse and the parameters of the plasma layer formed at the foil surface. It was found experimentally that an additional plasma current channel forms on the surface of a 120-μm stainless-steel foil at a linear current density of 0.25–0.5 MA/cm, which corresponds to a magnetic field of 0.3–0.6 MG. For the same conditions, one-dimensional computer simulations of the foil heating were performed in an MHD model by using a wide-range semiempirical equation of state for stainless steel. The calculated threshold for plasma generation on the foil surface is compared with the experimental data. The main parameters of the plasma layer are also calculated at linear current densities of 2–10 MA/cm, which far exceed the threshold current density. The plasma layer parameters as functions of the linear current density are determined for the case of an iron foil.     

Study of morphological and symbiotic traits during the ontogeny of supernodular and hypernodular pea mutants

Morphological (plant height and vegetative biomass amount) and symbiotic (number of nodules and nitrogenase activity) traits of six symbiotic pea mutants and the original cultivar Rondo were studied at different vegetation periods. Of the mutants studied, one (K10a) was supernodular and the remaining five (K1a, K2a, K5a, K7a, and K27a) were hypemodular. Essential distinctions in the absolute values and time course of the changes in individual morphological and symbiotic traits of different pea mutants were demonstrated. The supernodular type is inferior to the original cultivar in plant height and production of vegetative biomass, but exceeds it in nodulation and nitrogen fixation. The hypernodular mutants either surpass the original cultivar with respect to the production capacity or display similar results. The symbiotic traits—number of nodules and nitrogen fixation activity—of these mutants are higher compared with the Rondo cultivar. The mutants K1a, K2a, and K27a were demonstrated to be useful in breeding pea for an increase in nitrogen fixation.     

A sawdust-derived soil conditioner promotes plant growth and improves water-holding capacity of different types of soils

Sawdust, a bulky waste generated by wood processing industries, has very few profitable and ecofriendly uses and poses a problem of proper disposal. Treatment with the fungusVolvariella volvaceae and a dilute solution of urea converted sawdust from a phytoinhibitory material to a phytostimulatory soil conditioner. In different types of soils, the soil conditioner increased the moisture retention and facilitated the cohesive interaction of particles. Analyses of the major biopolymers of sawdust after fungal treatment indicated that levels of cellulose, hemicellulose and lignin decreased; however, these changes did not account for the plant growth stimulatory property attained by this material.     

Neuronal reactions in the dorsolateral pontine area during the immobility response in rats

Reactions of 277 neurones located in the brain pons dorsolateral portion were analised in staying awake and narcotized rats during immobility reflex, induced by the skin constriction on the neck dorsal surface. Got excited: fast adaptive tactile neurons (n = 32), interneurons (n = 42), and cells forming monosynaptic inputs to the parts of medulla oblongata, which inhibit the movements (n = 10). Were inhibited: somatosensory (n = 42), nociceptive (n = 24) and nonidentificated (n = 14) neurons. In some neurons charge characteristics were stable or slightly modified, namely: respiratory neurons (n = 16), cell group, having stable background firing (n = 72) and stimulating antidromically spontaneously silent ponto-medullar neurons (n = 22).     

Paradoxical vagal effects on the cardiac rhythm in cats

In anaesthetised cats, an increase in the vagal burst rate resulted in a paradoxical decrease of vagal bradycardia. This seems to be due to a shift of the vagal stimulus position towards early phase of cardiac cycle. The mechanism of this paradoxical effect depends on the magnitude of vagal chronotropic effect upon the time of vagal stimulus delivery within cardiac cycle.     

Neurochemical analysis of the amygdala basolateral nucleus of rats during anxiety tests

Chlordiazepoxid, phenibut, indoter, campiron, campironin, when administered into the amygdala, improve the anxiety condition of rats in avoidance tests and resemble by their effects dophamine, GABA, or serotonin. Observed differences in the anxiolytic effects between anxiosedative and anxioselective agents seem to be due to an unequal contribution of the monoamin- and aminoacidotergic transmitters into the mechanisms of heteromodal aversive anxiety genesis in the basolateral area of the amygdalar complex.     

Effects of delta-sleep-inducing peptide during ischemic injury of the rat brain

An anti-ischemic effect of the delta-sleep-inducing peptide (DSIP) was found in rats. The DSIP effect was more obvious than that of the MK-801. The data obtained is discussed considering a possible use of the DSIP for brain stroke prophylaxis.     

Gas exchange and oxygen transport during long term hypothermia following a hypothermal apnea in rats

The data obtained show that, at the initial stages of hypothermia, a decrease in the oxygen consumption and carbon dioxide production, cardiac output, and heart rate occurred in accordance with the temperature coefficient. Suppression of the tissue gas exchange was unrelated to disorders in the lung gas exchange but determined rather by a progressing weakening of heart activity, decrease in the cardiac output, and increase in the general vascular peripheral resistance.