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The reactions of dermal structures to subcutaneous injections of gold nanoparticles were studied in CBA mice. Routes of the nanoparticles migration after injection and the mechanisms of their effects on the adjacent tissues were studied. Injected nanoparticles were phagocytosed by macrophages; some of them migrated to lymphoid follicles of the lymph node, while others migrated into blood vessels, where the particles were released from the macrophage cytoplasm into circulating blood. The endothelium was destroyed as a result of the toxic activity of macrophages loaded with nanoparticles. Two mechanisms of angiogenesis inhibition and death of blood vessels in tissues after injection of nanoparticles were distinguished. One mechanism consisted in deactivation of macrophages producing vascular endothelium growth factor inducing the formation of endothelium in the growing blood vessels, but not in direct inhibition of this factor. The other mechanism was realized through direct death of the endothelium in migration of macrophages through the vascular wall.

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Physically transparent cornea, lens, and vitreous body are not transparent from histophysiological viewpoint and hence, cannot directly transmit light to the retina. The lens forms from two primordia in the course of the eye development: ectodermal (for capsular epithelium) and neuroglia (for lenticular stroma). These data suggest that the neuroglia migrating from the internal leaflet of the ocular goblet is a source of stromal fibroblasts of the corneal proper substance and also presents the fibroblast differons in the human ocular vitreous body and in the lenticular posterior pole. The common source in the development of the stroma of the transparent structures of the eye is explained and confirmed by the fact that the cornea, lens, vitreous body, and the retinal and brain neuroglia contain special proteins common for all these structures, crystallins. The structural relationship and origin of fibroblasts of the transparent ocular media underlie the identical functions of crystallin production; the physical and chemical characteristics of crystallins prevent the diffusion of light and cumulate it in one direction. In addition, our data on the neuroglial origin of the lenticular stroma suggest that the lenticular cells can act as Muller's glia, regulating the transformed energy flow. Hence, the fibers and stromal cells of the cornea, lens, vitreous body, and retinal glia can serve as components of the universal conduction system perceiving light, transforming it into another type of energy (presumably into electromagnetic waves or some motor pulse), and only then sending it to the photosensor cells. As a result, we have one-way light conduction due to stromal cells of transparent eye structures and inability of the retina to identify these cells. We therefore conclude that the cells located in front of the retina are invisible for the photoreceptors, because they conduct stimulation being not transparent in the physical sense, but just physiologically. We see only what this unique conduction system allows us to see.

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This work was designed to study changes in the nervous apparatus of the blood vessels in the brain and spinal cord with a view to developing methods for the determination of the biological age in man. Pial and intramedullary vascular systems of the brain and spinal cord were examined in different periods of postnatal ontogenesis (between the age of 1 and 90 years) using histological, fluorescent-histochemical, and immunohistochemical methods as well as by ink injections into the blood vessels, scanning and transmission electron microscopy. The data obtained on the age-related rearrangement of the nervous apparatus of the arterial vessels in the brain and spinal cord have not only theoretical significance but can also be used for the solution of practical problems encountered in the practical work of forensic medical experts.

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The heterodyne technique has a number of advantages over the homodyne technique when an accurate characterization of particle-size distribution (PSD) of heterogeneous systems is required. However, there are problems related to acoustic vibrations that make it difficult to take advantage of the heterodyne technique. An instrument developed for quasi-elastic light scattering (QELS) that uses the optical heterodyning principle is described. Vibration-related problems are considerably reduced because of the incorporation of all optical elements into one solid optical block. A real-time correlation analysis of the photocurrent fluctuations is performed by a PC-embedded analog-to-digital converter card with a digital signal processor. Investigation of the PSD in biological fluids for medical diagnostics is presented as a typical application. A diagnostic analysis of the PSD requires a simultaneous processing of a huge number of QELS data. An original statistical algorithm to accomplish this analysis has been developed. Technical specifications of instrumentation for heterodyne QELS measurement are discussed.

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We have studied the large-scale internal fluctuations in DNA coils by using quasi-elastic light-scattering spectroscopy. We have measured the angular dependence of the first cumulant of the scattered-light autocorrelation function. Within the q (3) domain of this dependence, we observed the transition from the asymptotic behavior predicted for good solvents to the asymptotic behavior predicted for ? conditions. This allowed us to determine the screening length of volume interactions in DNA chains. Analysis of the autocorrelation functions by a regularization procedure allowed us to reconstruct the mode composition of the scattered light and to determine the relaxation time of the fluctuations in the coil size.

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The authors observed two cases (males aged 21 and 23) of long-term body hyperthermia in the orthostatic posture. Clinical examination detected left-sided stage III-IV varicocele. Elevation of body temperature was stopped by ligation of the testicular veins. A long-term follow-up showed a good response.

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At investigating brains of humans, rabbits and pigeons by means of the cytochemical method, using peroxidase-++--antiperoxidase complex, an immune positive reactivity to ++leu enkephalin has been revealed in neurons of the substantia nigra, in the grey substance of the aqueduct area, in the posterior nucleus of the cochlear nerve, in the ventral part of the giant-cellular reticular nucleus in the nucleus of the solitary tract and in capillaries of the brain also. By means of some ultrastructural investigations certain places have been determined where synapsis and deposition of neuropeptides take place. These are specialized endotheliocytes, pericytes and neurons, situating especially close to the capillary wall.

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By an indirect immunohistochemical method with fluorescein-isothiocyanate (FITC) and horse radish peroxidase as markers (HRP) the presence of vasopressin was shown in cells of dura mater in white rats. Mast cells were identified after staining with methylene blue by the metachromatic granularity of the cytoplasm. It was shown that the number of cells found by means of FITC luminescence corresponds with their number found by means of methylene blue. The use of conjugate with HRP unveils a lesser number of vasopressin-containing cells.

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In an immunochemical study of the melanocytes of the brain blood vessels in man, the presence of vasopressin has been demonstrated. The endings of cholinergic axons terminate on the surface of these cells. It is assumed that the melanocytes participate in regulation of the motility of the arteries of the brain.

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Fluorimetric methods were used to determine adrenaline, dopamine, noradrenaline, serotonin and tryptamine in the pia mater of the brain and spinal cord of various vertebrates (fishes, birds, mammals) and of man. The histochemical method using glyoxylic acid showed the presence of biogenic monoamines in adrenergic nerve fibres and in the monoaminocytes. Their total amount in the pia mater is roughly the same, except in man, in whom it is significantly lower. From the higher adrenergic axon concentration on the one hand and the lower number of monoaminocytes on the other, it can be concluded that the neuronal factor has a more important role in the regulation of brain haemodynamics in man.

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By means of immunochemical method the presence of vasopressin in the melanocytes of the man's brain arteries was found. The terminals of the cholinergic axons come to an end on the surface of these cells. It is suggested that the melanocytes take part in the regulation of the brain arteries mobility.

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Receptor glomeruli have been studied in the arterial walls of the pia mater of the human brain and spinal cord by means of the light and electron microscopy methods. Zone of their high concentration have been stated; three types of receptor glomeruli have been determined, as well as 3 types of ultrastructural organization of sensitive terminals.

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Fluorimetric studies have been made on the content of adrenalin, noradrenaline, serotonin, dopamine, and tryptamine in the pial matter of the brain and spinal cord of fishes, birds and mammals including man. Using histochemical method with glyoxylic acid, biogenic monoamines were revealed in the adrenergic nerve fibers and monoaminocytes. Their total content in the pial matter of the brain is approximately the same in all vertebrates, being significantly lower in man. Higher concentration of adrenergic axons and lower amount of monoaminocytes in human subjects reveal the key role of the nervous influences in regulation of hemodynamics of the brain.

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By means of indirect immunofluorescent method vasopressin localization has been defined in neurons of the locus coeruleus, in terminals, converging to the substantia nigra cells and the sylvian aqueduct area, as well as in the granule-containing cells of the human cerebral blood vessels. The granule-containing cells are identified as melanocytes, when investigated by comparative light-optic and electron microscopical technique. The melanocytes of the cerebral vessels have various size and form in accordance to their different functional state. In some melanocytes peptide vesicles are revealed. This demonstrates a possible synthesis of vasopressin. It is supposed that local endocrine regulation of the cerebral hemocirculation is performed by cooperation of granule-containing cells, producing hormones with oppositely++ directed constrictor and dilatator action to the vessels.

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