Biomedical subjects
Publications and source records attributed to E I Ivanov.
A partial-wave analysis of the mesons from the reaction pi(-)p --> pi(+)pi(-)pi(-)pi(0)pi(0)p has been performed. The data show b(1)pi decay of the spin-exotic states pi(1)(1600) and pi(1)(2000). Three isovector 2(-+) states were seen in the omegarho(-) decay channel. In addition to the well known pi(2)(1670), signals were also observed for pi(2)(1880) and pi(2)(1970).
An amplitude analysis of an exclusive sample of 5765 events from the reaction pi- p-->eta'pi- p at 18 GeV/c is described. The eta'pi- production is dominated by natural parity exchange and by three partial waves: those with J(PC) = 1(-+), 2(++), and 4(++). A mass-dependent analysis of the partial-wave amplitudes indicates the production of the a2(1320) meson as well as the a4(2040) meson, observed for the first time decaying to eta'pi-. The dominant, exotic (non- qq) 1(-+) partial wave is shown to be resonant with a mass of 1.597+/-0.010(+0.045)(-0.010) GeV/c2 and a width of 0.340+/-0.040+/-0.050 GeV/c2. This exotic state, the pi1(1600), is produced with a t dependence which is different from that of the a2(1320) meson, indicating differences between the production mechanisms for the two states.
This report describes a method for measuring the respiratory burst in neutrophils, based on intracellular oxidation of the reduced ethidium bromide derivative, hydroethidine. Fluorescence of the resultant product quantitatively determined by flow cytofluorometry serves as a measure of the neutrophil ability to generate superoxide radicals. We found that during inflammation some polymorphonuclear leukocytes showed a considerably lower respiratory burst response to phorbol myristate acetate treatment. It was demonstrated that variations in this parameter could be an indicator of the course of inflammation.
The oxidative and phosphorylating functions of mitochondria (M) and their ultrastructure were studied in the myocardium of normal and 6.5-hour immobilized rats that belonged to different zoosocial groups. M from dominant rats under normal conditions were shown to exhibit higher energy and to possess better respiratory energy regulation than those of "outcast" rats. However, the ultrastructure of M had no group specificity in normal. The immobilization caused more profound changes in M from the dominant rats and led to a more pronounced swelling of M in the myocardium of the above rats than in the "outcast". M from the subdominant rats were most resistant to an immobilization stress.
Immobilization stress induced catecholamines level changes were studied in brain nuclei, taking part in blood pressure central regulation in rats with different zoosocial position. The significant differences in catecholamines level between the zoosocial groups of rats were shown in dopamine synthesized hypothalamic nuclei-n. arcuatus, n. periventricularis and noradrenaline synthesized-n. subcoeruleus++. The dominant rats were characterized by the highest catecholamines level.
Effect of immobilization stress on myocardial ultrastructure has been studied in rats occupying, according to the behavior, dominant, subdominant and "outcast" position in the group. The greatest changes are revealed in the myocardium of the dominant rats. This is explained by the fact, that mechanisms ensuring realization of certain functional systems in these animals require maximal energetic and emotional expenditure. And as the result--compensatory ability of their physiological function is lower than in animals of other ranks.
A modified open-field test was used in the experiments on rats. It was shown that animals 6 days after bilateral coagulation of locus coeruleus displayed weight changes and some behavioural parameters distinct from those of sham-operated and control animals. The most pronounced differences observed in animals after locus coeruleus coagulation, as compared to the control, were inversion and adaptive responses to a sudden brief stimulus, locomotor dysfunction and absence of response to handling.
Explore the source record for details and available documents.