[Hepatocellular mechanisms of compensatory processes influenced by environmental chemical factors]

The hepatocellular compensatory mechanisms against chemical pollutants were investigated. They expressed in hypertrophic nucleus-nucleolus structures, increased DNA-synthetizing and proliferative activity of hepatocytes, activated hepatic bile secretion and metabolic rearrangement in hepatocytes.

Low-density lipoproteins interact with liposome-binding sites on the cell surface

Under physiological conditions significant amounts of low-density lipoprotein LDL particles ar taken up by cells independently of specific high-affinity LDL receptors (apo-B receptors). Previously it was established that some cells contain surface sites capable of binding liposomes. We proposed that liposome-binding sites could contribute to LDL interaction with the cell surface via phospholipid molecules of LDL particles. To check this hypothesis we studied the competitive interaction of human LDL and DPPC liposomes with mouse embryo fibroblasts depleted of apo-B receptors by preliminary incubation with LDL. We have found that after removal of the liposome-binding sites from cell lamellae these areas of the cell surface lose their ability to bind LDL.

[Rheovasography in the evaluation of conservative treatment methods in obliterating atherosclerosis]

The work discusses the results of treatment of 65 patients for arteriosclerosis obliterans of the lower limb vessels by means of various nonoperative methods. The clinical indices improved within the shortest period of time in the group of patients treated by a complex of measures including reinfusion of blood irradiated by ultraviolet rays. According to the findings of rheovasography, the rheographic index increased to a greater degree (+0.4) in patients who were treated by infusion of their own blood, which had been exposed to ultraviolet light, in combination with intravenous injection of drugs. Application of quantum hemotherapy alone was also effective, which was confirmed by increase of the rheographic index by 0.2. It is pointed out that the therapeutic effect of the method is mainly due to improvement of the blood rheologic properties and provision for the flow of blood along the main channel.

[The effect of pesticides on the development in rats of osteosarcomas induced by 90Sr]

In experiments with rats the authors have assessed the development of remote effects of radiation (90Sr) combined with chronic exposure to chlorophos and lindane within a wide range of doses. It has been shown that chronically administered chlorophos and lindane have no carcinogenic and cocarcinogenic effects.

[Use of laser irradiation in the complex ambulatory treatment of arthrosoarthritis]

The article discusses experience with the treatment of 60 patients with arthrosoarthritis deformans of various large joints by the traditional conservative methods and with the use of laser radiation by an Uzor biomedical laser device. The authors noted a positive effect of laser radiation on the pathological processes developing in the region of the involved joint, which reduced the terms of treatment from 24.4 to 10.4 days and considerably reduced the number of recurrences in the immediate period.

[Changes in lymphocyte size after chronic exposure to radiation and chemical factors]

Results of the analysis of changes in peripheral blood lymphocytes size under chronic exposure to external gamma radiation and pesticide chlorophos++ in combination and separately are presented. It has been found out that under exposure of animals to radiation or the pesticide it is small and big lymphocytes respectively which most significantly suffer quantitatively. Under the joint radiation ++-chemical exposure of the organism the number of both types of cells is reduced simultaneously.

[Hypoinsulinemia and lipid peroxidation in emotional-pain stress]

The development of emotional pain stress in rats is accompanied by an increase in lipid peroxidation (LPO) products in the pancreas and a decrease in antiradical activity of its lipids. Hypoinsulinemia, of which a degree of expression is inversely proportional to an increase in peroxidation products, is observed. Antioxidant administration prevents LPO process activation in the pancreas and inhibits, to a great extent, a decrease in the level of insulin in stress. It is assumed that a certain role in the development of hypoinsulinemia in stress can be played by LPO processes resulting in the formation of active forms of oxygen and damage of the islands of Langerhans of B-cells.

[Surgical treatment of myasthenia gravis in children]

The article deals with the treatment of myasthenia in 33 children whose ages ranged from 3 to 15 years. Myasthenia of moderate severity was diagnosed in 14, severe in 15, and extremely severe in 2 children. To make a precise diagnosis, loading, neostigmine methylsulfate, cold, and D-tubocurarine tests were conducted. Thymectomy was performed in 32 patients. The operation was carried out through a T-shaped sternotomy approach. Thymogenic myasthenia was verified in 31 patients and thymomogenic only in one patient. There were no fatal outcomes. The late-term results were studied in 12 patients in follow-up periods of 3 to 6 years. Adaptational activity of the patients, anticholinesterase agents and the results of stimulant electric myography served as the criterion in appraising the late-term results. Modern diagnostic methods and surgical intervention ensure a favourable result in 75% of patients.

[The development of a questionnaire scale for determining individual hypnotizability]

Based on the MMPI test the authors developed a scale-questionnaire for predicting the degree of individual hypnotizability before realization of hypnotherapy. Forty-two assertions were singled out, affirmative answers to which make it possible to determine the probable hypnotizability of the subject according to a special scale comparable with the Katkov scale for assessment of the "depth" of the hypnotic state.

[Effect of low-molecular toxic substances on the organs of the immune system in mothers and their offspring]

Administration of benzpirene to the mother is accompanied with activation of B-and decrease in T-links of immune activity both in the mother and offspring. The lymphoid organs in the animals, not subjected antenatally to benziprene action, but given the substance after birth, undergo destabilization and are not ready to administration of this polycyclic hydrocarbonic compound. This produces their hypoplasia. It is quite possible, that under this condition the activity of the cellular link of immunity decreases, and the humoral one is stimulated. Certain morphofunctional connections are supposed to exist between the immune systems of the mother and the fetus. The antenatal action of benzpirene causes a responsive reaction in the offspring as an immunological commemoration, and it ensures the level of the immune response.

[Development of spatial orientation during pilot training]

The problem of spatial orientation of pilots flying high-altitude aircraft is in the focus of present-day aviation medicine because of a growing number of accidents in the air. One of the productive lines of research is to study spatial orientation in terms of active formation and maintenance of its imagery in a complex environment. However investigators usually emphasize the role of visual (instrumental) information in the image construction, almost ignoring the sensorimotor component of spatial orientation. The theoretical analysis of the process of spatial orientation has facilitated the development of the concept assuming that the pattern of space perception changes with growing professional experience. The concept is based on an active approach to the essence, emergence, formation and variation in the pattern of sensory perception of space in man's consciousness. This concept asserts that as pilot's professional expertise increases, the pattern of spatial orientation becomes geocentric because a new system of spatial perception evolves which is a result of the development of a new (instrumental) type of motor activity in space. This finds expression in the fact that perception of spatial position inflight occurs when man has to resolve a new motor task--movement along a complex trajectory in the three-dimensional space onboard a flying vehicle. The meaningful structure of this problem which is to be implemented through controlling movements of the pilot acts as a factor that forms this new system of perception. All this underlies the arrangement of meaningful collection of instrumental data and detection of noninstrumental signals in the comprehensive perception of changes in the spatial position of a flying vehicle.

[Activation of lipid peroxidation in the brain in cerebral hemorrhage]

The effect of intracerebral hemorrhage (injection of 0.15 ml of autogenic blood during 2 min in capsula interna) on lipid peroxidation in brain tissue was studied in rat experiments. Intracerebral hemorrhage resulted in a progressive increase of conjugated diene and malonic dialdehyde concentrations, and a decrease in the levels of cerebral lipids antiradical activity. This effect appeared by the 3-rd hour and was significantly manifest 24 hours after the blood injection into the brain.

[Role of optokinetic stimulation in realizing vestibulospinal reflexes]

This paper presents data about the effect of optokinetic stimulation (OKS) on vestibulospinal reflexes and discusses mechanisms of interaction of the vestibular, optic and proprioceptive sensors during their combined stimulation. The vestibulospinal reflexes were investigated using a 2-minute step test and simultaneous OKS that was produced by a portable optokinetic drum mounted on the head of the test subject. During the tests optokinetic nystagmus was recorded and the angle of body rotation relative to the initial position was measured. It was found that during the step test the body turned along the OKS direction, i. e. towards the slow component of optokinetic nystagmus. During leftward OKS the angle of rotation was larger than during rightward OKS: 406.4 +/- 75.9 deg and 207.5 +/- 40.7 deg, respectively. During leftward OKS loss of equilibrium was recorded 4.5 times more often than during rightward OKS. It has been demonstrated that the capacity to track stimuli moving to the left is lower than that to pursue stimuli moving to the right. It has been shown that there is a correlation between the rate of the optokinetic nystagmus slow phase and the angle of body rotation during the step test. It has been concluded that optokinetic nystagmus can be used as an informative parameter when measuring statokinetic stability in response to multisensory stimulation.

[Use of ultrasonics in the fixation of autologous skin transplants]

Based upon his clinical experience the author proves advantages of the ultrasonic welding for the transplant fixation in skin plasty with using cyacrine as joining material.

[Formation of images of spatial position during the development of illusions of vestibular origin]

This paper discusses specific features of pilot's spatial orientation in response to spatial illusions of vestibular origin associated with their recognition and management. Analysis of data in the literature and observations by the present authors allow the conclusion that pilot's spatial orientation, once spatial illusions have emerged, makes him assess not only the instrumental information but also the pattern of his own controlling movements. As a consequence, it is suggested that in relation to the formation of a correct image of spatial position (particularly in the case of spatial illusions) pilot's controlling movements act as part of instrumental information concerning the spatial position of the flying vehicle.

[Effect of lipid peroxidation on the insulin receptor in rat adipocytes]

Lipid peroxidation is studied for its effect on insulin receptors in isolated rat adipocytes. The results suggest that addition of two peroxidants (3 mM cumene hydroperoxide and 0.2 mM Fe2+) leads to malondialdehyde accumulation and binding inhibition through insulin receptors quantity and affinity decrease.

[Participation of lipid peroxidation in complement-mediated hemolysis]

Activation of lipid peroxidation (LPO) was recorded during complement-mediated erythrocyte cytolysis. It preceded hemoglobin release and was, presumably, the reason for pore formation in cell membranes. Correlation between the formation of Schiff bases and the decrease in malondialdehyde concentration is suggested.

[Use of central electroanalgesia to restore the body's functional state in motion sickness]

Central electroanalgesia (CEAN) is a technique that involves application of pulsating current to the central nervous system in order to enhance its tonicity recover autonomic equilibrium and to reduce parasympathetic cardiovascular reactions. In two experimental runs in which 9 volunteers participated the efficacy of CEAN in preventing motion sickness symptoms produced by Markaryan's test was studied. After two rotations repeated with a one-hour interval vestibular reactions persisted for 7-10 hours. CEAN had a positive effect: after a one-hour CEAN session applied between two rotations the tolerance time of the second rotation increased on an average by 76%. An additional exposure to CEAN after rotation eliminated almost completely the adverse effects of rotation and made effective the postrotation work. Due to CEAN parasympathetic reactions of the cardiovascular system typical of the postrotation recovery period were indistinct. These data suggest that CEAN is an effective method to be used to help a rapid recovery of the functional state of the human body during motion sickness.

[Interaction of acrylates with the microsomal oxidation system in the rat liver]

Esters of acrylic and methacrylic acids (methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate) binding with cytochrome P-450 in rat liver microsomes, formed the spectral complexes of the first order with maximal extinction at 381-388 nm and minimal--at 416-425 nm. Dimethylaniline, used as a classical substrate of oxidation in reactions catalyzed by cytochrome P-450, inhibited the complexes formation by the mixed type. Acrylates increased the oxygen consumption and NADPH oxidation in rat liver microsomes.

[Effect of rotation and vibration on orientation in man in relation to the gravitational vertical]

The man's ability to get oriented in relation to the gravitational vector was investigated. The test subjects were exposed either to rotation in 1 m arm centrifuge or tilting in a chair. They were simultaneously exposed to total-body vertical vibration of 20 Hz. As the exposure continued, the ratio of the perceived vertical (in the absence of visual keys) and the apparent body position changed significantly. It is concluded that the tests used to evaluate the pilot ability for spatial orientation should include evaluations of the subjective vertical and body position relative to the gravitational vector. The tests should be performed during exposures to simulated dynamic flight factors.

[Interaction of methylmethacrylate and acrylamide with the microsomal oxidation system of the rat liver]

A complex, exhibiting the maximal absorption at 385-388 nm and minimal at 414-420 nm, was formed after interaction between cytochrome P-450 and methylmethacrylate and acrylamide at 5 mM concentration. Acrylamide at concentrations higher than 6 mM induced the formation of modified type 11 differential spectra with maxima at 418 nm and minima at 385 nm. Methylmethacrylate and acrylamide stimulated utilization of NADPH and inhibited hydroxylation of 3,4-benzpyrene. Methylmethacrylate inhibited also N-demethylation of aminopyrine. After treatment of rats with the monomers activities of cytochromes P-450, b5 and NADPH-cytochrome c reductase were unaltered. Methylmethacrylate and acrylamide appear to interact with the microsomal oxidative system.

[Use of antioxidants for preventing the hepatotoxic effect of acrylonitrile]

The authors examined the possibility of using antiooxidants in the chemoprophylaxis of poisonings with alkylating chemical compounds. It was demonstrated that vitamin E, ionol and low-molecular thiols (cystein, glutatione and unithiol) prevent the increased permeability of plasma membranes and impairment of the protein-synthesizing function of the endoplasmic reticulum of hepatoytes in acute and chronic acrylonitrile poisoning.

[Lipid peroxidation in the liver of rats with alloxan diabetes]

Experiments on white male rats were performed to study lipid peroxidation in the rat liver at varying times of the development of alloxan diabetes. After administering alloxan in a dose of 16 mg/100 g bw both non-enzymatic and enzymatic lipid peroxidation in the liver was substantially activated, while the blood glucose level ascended. Injection of insulin to rats with alloxan diabetes entailed a reduction of the blood glucose content and the formation of the final product of lipid peroxidation, malonic aldehyde (during non-enzymatic process). Pretreatment of the rats with alloxan diabetes with the synthetic antioxidant BHT in a dose of 30 mg/kg bw prevented activation of lipid peroxidation, substantially decreasing the blood glucose content. It is concluded that the alloxan-induced activation of lipid peroxidation plays an essential role in the mechanism of alloxan action.

[GABA-ergic system components and lipid peroxidation in acute exogenous acrylonitrile poisoning]

A study was made of the content of biogenic amines as of a number of functions of the plasma membrane of hepatocytes and activity of lipid peroxidation during acute acrylonitrile poisoning. This industrial monomer stimulated all the parts of the sympatho-adrenal system and caused a reduction of the GABA level that is likely to be a consequence of inhibition of glutamate decarboxylase biosynthesis. Moreover, it was found that barrier and regulatory functions of the hepatocyte membrane were impaired. Accumulation of diene conjugates and protective action of alpha-tocopherol that prevented the development of the discovered stressor alterations point to a possible pathogenetic relationship between the disorders seen and poison-induced lipid peroxidation.