Changes in the Intensity of Respiration during Ontogenesis of Some Invertebrates

We studied the dynamic of respiration intensity during ontogenesis of flat worms (Dugesia tigrina), molluscs (Anodonta piscinalis and Viviparus viviparus, and insects (Leptinotarsa decemlineata). In planarians that reproduce vegetatively, the intensity of respiration increases just after fission and decreases at the subsequent phases of growth. In A. piscinalis, this index of metabolism increases during embryonic and early larval development and decreases at the later developmental stages. In V. viviparus, which develops in the female genital tract, the intensity of respiration remains unchanged during embryogenesis and decreases during late embryogenesis and subsequent phases of growth. In L. decemlineata, the intensity of respiration increases during embryonic and early larval development and then decreases to undergo cyclic changes times to molts. This index markedly decreases in the pupae, increases in the beginning of imaginal period, and then again decreases.     

Comparative characteristics of psychoemotional patterns in Albino and Wistar rats

Analysis of psychoemotional behavioral component in Albino and Wistar rats during solving a cognitive task showed that intra-population differences were determined by the relationship between passive and active forms of unconditioned reactions. Quick-learning rats from both populations were characterized by the dominance of active forms of psychoemotional reactions over the course of training. The learning process in slow-learning rats was accompanied mainly by passive emotional manifestations, whereas active reactions dominated at the stage of habit realization. Passive forms of manifestations prevailed over active forms over the course of training in both Albino and Wistar rats which failed to solve the task. The interpopulational psychoemotional differences were quantitative and depended only on the learning styles. Wistar strain was characterized by a decreased percent of animals which were able to solve a cognitive task (40% versus 80% in Albino rats), affective flatness and decreased tolerance to information loadings.     

Factors of activation and stabilization of DNA-methylases from Shigella sonnei 47 and Mycobacterium smegmatis butyricum cells

A comparative study of factors of activation and stabilization of individual DNA-methylases from two bacterial strains--Shigella sonnei 47 and Mycobacterium smegmatis butyricum--isolated by isoelectrofocusing in a pH gradient has been carried out. Storage of enzymes at +4 degrees C (pH 7.5) is accompanied by periodic changes in the methylating activity. No such changes are observed when the enzymes are stored at pI of the protein. In this case the methylases with alkaline or close to neutral values of pI remain stable over a period of at least two weeks, whereas acidic proteins are irreversibly inactivated by the end of a two-week period. A stabilizing effect of BSA on DNA-methylases of Sso 47 and Mbu strains has been demonstrated. A direct correlation between the stabilizing effect of BSA and the degree of enzyme purity has been established. Ca2+ appear to be a universal activator of methylases of the above strains; these cations produce a potent, although a short-term effect and can be used in the production of enzyme preparations with a high specific activity in DNA recombinant technology. Protease inhibitors do not exert any appreciable effect on the methylase activity upon storage. Storage at -20 degrees C and at neutral pH leads to complete inactivation of all DNA-methylases within 24 hours. In this case glycerol is fairly ineffective as a stabilizing agent.     

Inhibition of Human Blood Acetylcholinesterase and Butyrylcholinesterase by Some Alkaloids

A comparative study has been carried out on effects of berberine (diisoquinoline alkaloid) and sanguinarine and chelidonine (benzophenanthridine alkaloids( on erythrocyte acetylcholinesterase and serum butyrylcholinesterase from human blood. The studied alkaloids have been shown to be strong reversible inhibitors of the cholinesterase activity. Acetylcholinesterase is more sensitive to their action, than butyrylcholinesterase. The type of reversible inhibition was determined, and inhibitor constants were calculated. It is revealed that the character of inhibition is identical for the both cholinesterases. Berberine and sanguinarine are competitive-noncompetitive inhibitors, whereas chelidonine, a competitive inhibitor.