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Biomedical subjects

V A Shakhlamov

Publications and source records attributed to V A Shakhlamov.

At least 19 recordsLinked to original sources

[Structural-biochemical reorganization of rat liver caused by hydrogen sulfide-containing gas mixture].

Morphological equivalents of hepatocyte response to environmental factors of various intensity, associated with biochemical processes and directed at cell survival were studied in white outbred male rat using morphological (light and electron microscopy, histoautoradiography) and biochemical methods. As judged by the responses of intracellular structures, an exposure to hydrogen sulfide-containing gas, a pathogenic environmental factor, results in unequal changes in hepatocytes in different lobule zones. Small doses cause an activation of metabolic processes in hepatocytes that have plastic directivity. High doses of hydrogen sulfide-containing gas mixture result in the appearance of some signs of hepatocyte adaptation to extreme situation. Positive dynamics of structural modifications of the liver after the administration of nootropil and vitamin complex with antioxidant properties as correcting substances, indicates the reversibility of hepatocyte changes following long-term (up to two weeks) exposure to low doses and short-term exposure to high doses of hydrogen sulfide-containing gas mixture.

Air Pollutants↗

Ultrastructural and morphometric characteristics of nerve cells and myelinated fibers in the cerebral cortex after chronic exposure to natural gas containing hydrogen sulfide in low concentrations.

We studied ultrastructural and morphometric characteristics of nerve cells and myelinated fibers in the cerebral cortex after chronic exposure to natural gas containing hydrogen sulfide in low concentrations. Radioisotope assay revealed activation of protein synthesis in nerve cells after chronic exposure to natural hydrogen sulfide-containing gas in low concentrations (10 mg/m(3)by H2S) for 2 weeks. After 1 month the ultrastructure of myelinated fibers was characterized by sectorial loosening and demyelination.

Air Pollutants↗

[Ultrastructure of the cerebral cortex after exposure to gas containing hydrogen sulfide].

In experimental animals exposed to hydrogen sulfide-containing gas, electron microscopic study of cerebral cortex indicated the variability in the reaction of layer V neurons: along with neurons demonstrating irreversible damage, some cells with single signs of alteration were found. The reaction of different types of glial cells was also non-uniform. During initial 12 h following single exposure, oligodendrocytes showed the signs of intensified endocytosis. Following repeated exposures, severe destructive changes were found in myelinated nerve fibers and in single neurons, in which the karyolysis and cytoplasmic swelling were observed.

Administration, Inhalation↗

[Ultrastructural changes in the aortic arch intima in rats with various resistance to emotional stress].

Experiments were performed on 24 male Wistar rats weighing 210 +/- 14 g. Depending on the activity in the open field test, all rats were divided into behaviorally active and passive subgroups. Water-immersion stress (2 hrs) followed by 2-hrs rest period was used as the model of acute emotional stress. Tissue samples from aortic ascending arch were taken from control and stressed rats immediately after decapitation and used for further electron microscopy. The number of micropinocytosis vesicles along the free and basal layers of the cytoplasm and the area of mitochondria were determined. Emotional stress was shown to intensify metabolic processes involving micropinocytosis vesicles between the aortic lumen and its wall. Passive rats display the most severe alterations induced by stress (damages of aortic endotheliocytes, partial regeneration of the plasmalemma by membranes of micropinocytosis vesicles, and decrease in the average area of mitochondria). Morphological equivalents of the initial stages of emotional stress-induced formation of fibrous changes in the aortic arch intima are believed to be found. Such changes can lead to the appearance of atherosclerotic patches.

Animals↗

[Change in the content of chemical elements in epitheliocytes of the prickle cell layer of granulating skin wounds exposed to ultraviolet rays and ultraviolet laser therapy].

Spinous layer of human epidermis was studied in control group (2 human subjects) and in 16 patients with thermic lesions prior to and following ultraviolet laser therapy (UVLT) of ultraviolet irradiation (UVI). Skin biopsy was performed in each patient on undamaged regions (individual control). Chemical elements (Ca, K, Cl, Mg, Na and Al) content prior to and following treatment was compared. Patients with equal stage (IIIB) and localisation of lesion were selected. Bioptates were obtained for diagnostic purposes. UVLT was established to prompt normalization of the content of chemical elements named in epitheliocytes of human epidermis in IIIB lesions whereas UVI does not cause this effect at the same conditions. It is proposed that this difference is dependent on the origin of appropriate irradiations.

Adult↗

[The mapping of the local content of water and dry matter by using ultrathin frozen sections].

The possibility and applications of quantitative dry mass and water content mapping using an image analysis of darkfield intensity digitalization were shown on ultrathin freeze-dried cryosections. The distribution map obtained may be further used both for direct measurements of local dry mass and water content under physiological state and pathological disorders and for calculation of the concentration values obtained by quantitative X-ray mapping on freeze-dried cryosections in terms of millimoles per litre of cellular water.

Analog-Digital Conversion↗

[The morphological mechanism of the development of myosatellitocytes from the structural elements of the muscle fiber during increased functional activity of the skeletal muscles].

Under increased muscular activity in some muscular fibers disintegration areas of myofibrillar apparatus has been revealed. Migration of myonuclei into these microregions starts the mechanism of their segregation due to plasmolemma produced from the reticulum sarcoplasmaticum and triad systems surface. After plasmolemma production in "sarcocytes" intensive development and differentiation of organellae occur. As a result of differentiation "sarcocytes" transform in to myosatellitocytes of type-2 and migrate under lamina externa muscular fibers. So, a hypothesis about formation of myogenic tissue's cellular phase from the myosymplastic one has been confirmed.

Animals↗

[Ultrastructural and morphometric analysis of the Paneth cell reaction to administration of cholera toxin].

Experiments were made on 40 immature guinea--pigs which were divided into two groups. 20 animals received intraduodenal injections of cholera toxin and 20 others were injected normal saline (groups I and II, respectively). Group I animals exhibited a rapid fall in one--cell secretion of XS recorded on hour 6-12 after the injection of cholera toxin. Inhibition of functional activity was associated with defected synthesis of granules in the cells of Paneth.

Age Factors↗

[Morphological aspects of broad-plasma lymphocyte migration through ependymal cell of mammalian vascular plexus].

A morphological study of the cerebral vascular plexus was performed to find out the ways of blood cell migration from the vascular lumen into the liquor and in the opposite direction, as well as through ependymocytes. The material of the study consisted of cattle (cows and goats) with the body weight of 500 kg and 30-40 kg, respectively. From each animal species 16 animals were used in the study. Investigational methods included light and electron microscopy. Sequential stages of broad-plasma lymphocyte migration from the vascular lumen through endotheliocytes, capillary basal layer, connective tissue stroma, basal membrane of ependymocytes, as well as through proper ependymocytes have been revealed. The authors refer the phenomenon of broad-plasma lymphocyte migration to the phenomenon of emperipolesis.

Animals↗

[Clinico-morphological characteristics of a juvenile angiofibroma of the base of the skull].

203 patients with juvenile angiofibroma of the base of the skull were assessed clinicoanatomically. In addition to a routine otorhinolaryngological examination 60 patients underwent computed tomography, radioangiography and thermography. Biopsy specimens obtained at operations were studied morphologically for 133 patients including application of histotopography in 15 cases and electron microscopy in 19 cases. Two clinicoanatomic forms of juvenile angiofibroma (JAF) have been revealed as well as 4 vascular types and variegation due to different combinations of vascular, cellular and fibrillar components. According to biologic nature of JAF it should be referred to fibromatoses.

Adolescent↗

[Morphological changes in the filtration-reabsorption barrier of the remaining kidney after its denervation and disordered lymph outflow].

An electron microscopical investigation on combined effect of denervation and disturbance of lymphatic outflow to structural elements of the FRB in the preserved kidney after contralateral nephrectomy has been performed on 20 mature white rats in 3, 30, 180, 360 days. In 3 days in the cellular components of the FRB cytoplasmic structures are at the state of functional strain and overstrain. Hemostasis is observed in glomeruli and in peritubular capillaries, as well as edema of the interstitial connective tissue. In 30 days certain signs of hyperplasia and hypertrophy of intracellular structures appear in the components of the FRB. However, later (in 180, 360 days) certain tendency to predominance of processes of functional strain in the intracellular structures with their certain destruction and reaction of the connective stroma is observed.

Absorption↗

[Changes in the ionic composition and shape of erythrocytes in response to cholera toxin].

Blood of 10 inbred rats has been investigated after effect of cholera toxin for 1 h by means of roentgenospectral energetic spectrometer Revex-5100 (USA). Simultaneously, erythrocytes have been studied by means of the scanning electron microscope. Contents of sodium, phosphorus, chlorine, serum, potassium, and ferrum ions have been estimated. The cholera toxin changes the contents of the ions mentioned in erythrocytes and contributes to certain changes of their form. A suggestion is made that the cholera toxin changes permeability of the erythrocytes membranes without participation of the cell cyclase systems.

Animals↗