Increased affinity of liposomes derived from total spleen and liver lipids to spleen cells

The interaction of liposomes derived from total lipids of mouse spleen and liver with mouse spleen cells was studied. It was shown that the binding of these liposomes is much higher than the binding of liposomes obtained from a model lipid mixture--phosphatidylcholine--phosphatidylethanolamine--cholesterol (2:1:1). Adherent and nonadherent spleen cells were found to have affinity for liposomes derived from total lipids of spleen or liver. Removal of gangliosides and protein contaminants from the liposomes derived from total spleen lipids caused an increased binding of liposomes to spleen cells. Multilamellar liposomes bound more effectively to ultrasonicated vesicles having a homologous lipid composition than the liposomes with a different lipid composition. The increased affinity of liposomes derived from total lipids of spleen or liver for spleen cells may account for the identical fluidity of the lipid bilayer of liposomes and plasma membranes of spleen cells.     

Motor asymmetry of the forelimbs of the rat

Preference was studied of one of the forelimbs during performance of different manipulating movements in white rats. High degree of "handedness" was observed in all studied movements. However it was not absolute--no animals performed all movements by one and the same limb. Degree and character of "handedness" were different for different movements, though the number of "righthanded" rats in most tests as a whole exceeded the number of "lefthanded" ones. The "handedness" depends on the individuality of the animal, the character of the motor task, learning and interference of different motor tasks during training.     

The low-frequency EEG component in the healthy subject and its changes as affected by acutely developing foci at the level of the diencephalon and brain stem structures

The data are given of the analysis of the low-frequency EEG component (LF EEG--0.2--2.0 Hz) of 34 healthy subjects and 36 patients examined in dynamics in the acute period after operations: ablation of a tumour localized at the level of the diencephalon and the level of the brainstem. The LF EEGs were analyzed by a special program: auto- and crosscorrelation functions and power spectra were estimated. In the norm LF EEGs were characterized by mosaics, various frequencies and periodicity in various cortical areas, they appeared with interhemispheric asymmetry, depended on the EEG type--dominance or lack of the alpha-rhythm. In patients in the post-operative period the LF EEGs were changed; in favourable terminations, at first the period of oscillations and the coefficient of correlation increased, then they tended to normalization. In unfavourable terminations, with gross pathological foci in these areas, the LF EEGs acquired a synchronized character, with a higher frequency than in the norm.     

The electroencephalographic and autonomic correlates of the mental reproduction of emotional states]

The present study is devoted to the analysis of changes of bioelectrical and vegetative indices at mental reproduction of emotional states by man. Analysis is conducted of the data of mapping of intracortical interactions depending on the dynamics of R-R interval changes. Two stages of mental reproduction of emotions are revealed which are characterized by the presence of different centers of integration--in the frontal and temporal parts of the brain cortex. It is shown that at maximum emotional stress the integration center shifts from the frontal regions to the temporal region of the left hemisphere.     

Correlation of cutaneo-galvanic and voluntary reactions during recognition of emotional facial expressions

The frequency of skin-galvanic (SGR) and motor reactions was analyzed at recognition of human emotional state by mimics. 31 healthy persons and 54 patients with lesions of temporal and frontoparietal areas of both cerebral hemispheres were examined. It has been established that the process of recognition takes place by stages: at first - at intuitive level accompanied by SGR, and then at the level of making decision completed by a motor or verbal reaction. Efficiency of recognition at the first stage does not so much depend on lesion localization as at the second stage. Pathology of the left hemisphere affects mainly the stage of making decision, and of the right one - the process of recognition as a whole.     

Magnetic interaction of manganese with pheophytin anion-radical and chlorophyll cation-radical in reaction centers of the photosystem II

The influence of Mn on saturation curves of ESR spectra of Ph(-) and P(+)(680) at 1-200K in samples with different content of Mn has been studied. An analysis of these data and those on photoinduced changes of fluorescence yield of chlorophyll leads to the conclusion that the Mn-containing centre in Photosystem 2 is a cluster of 4 Mn atoms, two of which can be replaced by Mg(2+) or any other divalent metal. The distances between Mn Na Ph as well as between Mn and P(680) have been estimated.     

Mating behavior in Drosophila melanogaster males heterozygous for the dominant temperature-sensitive lethal mutation

The influence of two mutations on the mate success of Drosophila melanogaster males was studied. Dominant temperature-sensitive lethal mutations l(2)M167DTS and l(2)M65DTS were used in experiments. Both these mutations are recessive lethals in homozygote. Individuals l(2)M65DTS and l(2)M167DTS die at 17 and 28 degrees C, respectively. The mate success of l(2)M65DTS males is much lower than that of normal males. In the experiments conducted in autumn, l(2)M167DTS males were always at advantage, whatever their age. In the winter experiments, they were only at advantage at the age of 2-3 and 15-17 days. For l(2)M167DTS males, a relationship has been established between the mate success and t degrees, and season. The role of behavioural pleiotropic effects of mutations on the probability of their fixation in a population is discussed.