Rat Blood Leukocytes after Intravenous Injection of Magnetoliposomes on the Basis of Nanomagnetite.

The structure of blood neutrophils, eosinophils, monocytes, and lymphocytes and differential white blood count in adult rats were studied over 120 days after a single intravenous injection of magnetoliposomes based on nanomagnetite. Magnetoliposomes had no effect on the structure of neutrophils, eosinophils, monocytes, and lymphocytes. At the same time, injection of a suspension of magnetoliposomes based on magnetite nanoparticles led to a decrease in lymphocyte count and an increase in the count of monocytes and band and segmented neutrophils in the blood. These changes were transient and the parameters returned to normal by day 40-60 after injection.

[The cellular composition of explanted bioprosthetic heart valves in infective endocarditis]. / Kletochnyi sostav éksplantirovannykh bioprotezov klapanov serdtsa pri infektsionnom éndokardite.

OBJECTIVE: To perform immunohistochemical typing of cells as a component of bioprosthetic (BP) heart valves explanted during reoperations for prosthetic valve endocarditis. MATERIAL AND METHODS: The authors investigated 8 models of KemCor and PeriCor artificial heart valves produced by NeoCor Company (Kemerovo, Russia), which were explanted from the mitral position due to infection of xenogeneic implanted material. The following markers: CD3 (T-lymphocytes), CD20 (B-lymphocytes), CD34 and VEGFR2 (endotheliocytes), CD68 (monocytes/macrophages), vimentin (fibroblasts), and α-smooth muscle actin (smooth muscle cells), were used for immunohistochemical typing of cells as a component of the analyzed samples. RESULTS: Recipient cells were found to colonize devitalized BP tissues in infective endocarditis. This process simultaneously involved several types of cells performing their functions in infectious lesion and its initiation of BP remodeling. Macrophages contributed to the sanitation of the foci of infection and destruction of BP xenotissue; endotheliocytes ensured neovascularization and resistance of the implanted valve surface to infection; fibroblasts played a role in the neoplastic transformation of collagen, and smooth muscle cells were likely to take on the role in forming the elastic framework of a leaflet and in ensuring the mechanical properties of the bioprosthesis. CONCLUSION: In the time course of development of prosthetic endocarditis, the recipient cells populate xenovalve leaflets that are a modified extracellular matrix obtained from the porcine aortic valve complex. This process is a consequence of the destruction of the BP surface and deep components. The observed cellular reactions are likely to be adaptive and to be aimed at eliminating microorganisms and regenerating structural damages.

Influence of Sialadenectomy on the Development of Spermatogenesis in Rats: Ultrastructural Characteristics of Spermatogenic Epithelium and Leydig Cells.

Sialadenectomy in young rats modifies the development of the spermatogenic and steroidogenic functions of the testes. Sialadenectomy causes ultrastructural changes in spermatogenic cells, sustentocytes, and Leydig cells that disappear by week 8 of the experiment due to realization of compensatory and adaptive mechanisms. The effects of endocrine factors of the greater salivary glands on the spermatogenic cells are realized directly and indirectly via interstitial endocrinocytes and sustentocytes.

Structure of Rat Testicles after Intravenous Injection of Nanosized Magnetite Particles.

The structure of the testicles was studied in adult rats in 120 days after a single intravenous injection of chitosan-modified (magnetic nanospheres) and lipid-modified (magnetoliposomes) nanosized magnetite particles. Perls histochemical reaction detected in the testicular interstitial connective tissue the cells which absorbed and accumulated magnetite nanoparticles. The dynamics of spermatogenesis index and the count of Perls+ cells in the rat testicles were traced throughout the experiment. The studied modified nanosized magnetite particles did not penetrate through the blood-testicle barrier in rats.

Ultrastructural Characteristics of the Testicular Interstitial Endocrinocytes of Adult Rats Subjected to Total Sialoadenectomy.

The major salivary glands of rats release into the saliva and blood a wide spectrum of bioactive substances, essential for many organs, including the testes. Sialoadenectomy leads to the development of degenerative changes in the cells of the twisted testicular tubules. However, the effects of bioactive factors released by the major salivary glands on the morphology and function of Leydig cells remain little studied. Sialoadenectomy in adult rats led (in 1-4 weeks) to a decrease in the nuclear and cytoplasmatic areas of Leydig cells, violation of the plasmalemma integrity, dilatation of perinuclear space and agranular endoplasmatic reticulum vesicles, and to destruction of the mitochondria. Ultrastructural changes caused by sialoadenectomy completely resolved by week 6 of the experiment at the expense of compensatory activation of the synthesis of the major salivary gland factors by other sources in the organism of rats.

Ultrastructure of Rat Kidneys after Intravenous Administration of Modified Magnetite Nanoparticles.

The ultrastructure of nephrocytes of the proximal and distal convoluted tubules, podocytes, mesangial cells, and macrophages of the interstitial connective tissue was studied after single intravenous administration of magnetite nanoparticles modified with chitosan (magnetic nanospheres) or lipids (magnetic liposomes). Transmission electron microscopy showed ultrastructural features of absorption of magnetite nanoparticles. The shape, size, and number of vesicles containing nanoparticles in nephrocytes of convoluted tubules and macrophages after administration of the suspensions of magnetic nanospheres and magnetic liposomes were described.

Structure of Rat Lungs after Administration of Magnetomicelles Based on the Carbon-Coated Iron Nanoparticles.

We studied the effects of single administration of a suspension of magnetomicelles based on carbon-coated iron nanoparticles on the structure of rat lungs within 40 days. Histological analysis revealed a complex of hemodynamic alterations in the lungs. Described changes persisted in the lung stroma from day 1 until day 40, but their intensity decreased by the end of the experiment. Using immunohistochemical Perls reaction we identified cells morphologically corresponding to alveolar and interstitial lung macrophages. The number of Perls+ cells decreased by day 40 of the experiment. Ultrastructural analysis showed endocytosis of modified iron nanoparticles and their accumulation in intracellular digestionorganelles (endo- and lysosomes) of mononuclear phagocyte system cells. Accumulation of magnetomicelles in the lungs was not associated with damage to pneumocytes, macrophages, and blood-air barrier.

[SEXUAL DIMORPHISM OF MAJOR SALIVARY GLANDS IN RODENTS].

The review analyses the data on the structure of submandibular (SMG), parotid and sublingual salivary glands in rodents and on biologically active substances produced by them. The evidence is presented on the mutual influence of rodent major salivary glands (MSG) and the testes. Special attention is paid to gender differences of MSG in rodents, which are more fully apparent in mature individuals and are most pronounced in SMG. Sexual dimorphism is morphologically manifested in a larger size of secretory portions, the relative areas of granular and interlobular excretory ducts of SMG and greater number of granular cells of striated ducts of the sublingual glands in males. Biochemically sexual dimorphism is characterized by different amounts of biologically active substances secreted by the epithelial cells of secretory portions and granular cells of the ducts. Epidermal growth factor, nerve growth factor, kallikrein and other substances are synthesized in granular cells of the excretory ducts of all MSG in rodents, however, to the greatest extent ­ by SMG. The higher content of physiologically active substances in MSG saliva in males plays an important biological role.

[Liver, lung, kidney and spleen macrophages in rats after intravenous administration of the modified magnetite nanoparticles].

Using the immunohistochemical method, mononuclear phagocytes (MNPs) were detected in the liver, lung, kidneys and spleen of rats after a single intravenous injection of a suspension of magnetoliposomes and magnetic microspheres prepared on the basis of nanoscale magnetite particles of (NMPs). The dynamics of the of the number and topography of CD68(+)- and CD163(+)-cells in liver, lung and kidneys was characterized during 120 days after the intravenous injection of the suspension of modified NMPs. It was shown that NMPs surface modification reduced the degree and duration of macrophage activation. Signs of MNPs activation after the infusion of nanomaterial decreased in the following series: unmodified NMPs, magnetoliposomes, magnetic microspheres.

[Prooxidant and antioxidant activity of blood plasma and histology of internal organs of rats after intravenous administration of magnetite nanoparticles].

The effect of a single and multiple intravenous injections of a nanosized magnetite suspension on total prooxidant and antioxidant activity of blood plasma has been investigated by the method of luminol-dependent chemoluminescence. Magnetite nanoparticles possess dose-dependent prooxidant properties due to their iron atoms and at the same time their trigger compensatory activation of antioxidant systems in the rat blood plasma. After a single intravenous administration of magnetite the studied parameters of blood plasma returned to the normal level by the end of the experiment as due to removal ofnanoparticles from the body. In the case of multiple administration of the magnetite suspension dose-dependent changes in the pro- and antioxidant plasma activity persist during the whole experiment. Accumulation of magnetite particles in the cells of the mononuclear phagocytic system in the rats' liver, lungs and kidneys is associated with hemodynamic damages, local dystrophic and necrotic changes of parenchyma in these organs. After a single intravenous injection magnetite nanoparticles are identified in the rat organs for 40 days, but their number decreases by the end of the experiment.

[Cells of mononuclear phagocytes system of liver and lung in rats after intravenous application of magnetite nanoparticles].

The article describes changes in the morphology and localization of the cells of mononuclear phagocyte system of liver and lung in rats at different times after single and repeated intravenous administration of a suspension of nanoparticles of magnetite (NPM). Mechanisms for removal of nanoparticles of magnetite from the rat body with the participation of mononuclear phagocytes of the liver (removal of the particles by stellate macrophages in the gastroenteric tract with bile) and of the lung (by migration of the alveolar macrophages in the gleam of the bronchial tree) have been illustrated. It has been shown that intravenous application of nanomagnetite causes changes in the morphology of the internal organs of rats and the severity of these changes increases with increasing total dose injected magnetite.

Electron microscopy of rat liver after intravenous injection of nanosized magnetite suspension.

Rat liver was examined by transmission electron microscopy after a single intravenous injection of nanosized magnetite suspension (0.1 g (Fe(3)O(4))/kg body weight). Magnetite particles were found in Kupffer's cells and hepatocytes. Accumulation of the particles by these two cell types was different. Morphometry of magnetite-containing granules in Kupffer's cells and nanoparticle agglomerations in hepatocytes was carried out. The ultrastructure of Kupffer's cell granules was described and the mechanism of penetration of nanosized magnetite particles into the cells was suggested. Nanosized magnetite particles were not completely eliminated over 40 days after a single injection.

[Structural changes of some organs in rats after a single intravenous injection of magnetite nanoparticles].

The aim of this investigation was to study the morphological changes of liver, lung, kidneys and spleen as well as of the cells of mononuclear pahagocyte system in 60 rats 1-40 days after a single intravenous injection of a suspension of magnetite nanoparticles. Moderate hemodynamic disturbances and focal necrotic changes were detected in the hepatic and renal parenchyma. In the lungs and spleen, only hemodynamic disturbances were found. The degree of morphological changes in rat liver, lungs, kidneys and spleen was decreased by day 10. Using Perls histochemical method, the accumulation of nanoparticles was detected in the cells of mononuclear phagocyte system of the organs studied.

[Disperse endocrine system and APUD concept].

This review describes the problems of disperse endocrine system and APUD-system morphology, summarizes some debatable issues of single endocrine cell biology. The data presented refer to the history of both systems discovery, morphological methods of their study, developmental sources, their structural organization and physiological roles of their cells. The significance of single endocrine cells in the regulation of the organism functions is discussed.

[Liver, kidney and a lung structure in rats after intravenous magnetoliposome administration].

This work examines the effect of magnetoliposomes on the basis of Fe3O4 nanoparticles following different time intervals after their single intravenous injection, on the liver, kidney and lung structure in rats. Sections were stained with hematoxylin and eosin, and Perls method was used to demonstrate Fe+3 ions. It was shown that shortly after intravenous injection of magnetoliposomes, hemodynamic disturbances developed in all the organs studied, which by day 14 were aggrevated by focal necroses and dystrophic changes in the liver and kidneys. Accumulation of nanoparticles in the cells of mononuclear phagocyte system of these organs was demonstrated. Damaging effect of magnetoliposomes on liver, kidney and a lung structure was established, which was caused by ultradisperse Fe3O4 particles contained in them. The consequences of this influence for the rat organism at the time periods exceeding the duration of our experiment, may hardly be predicted.

[Biochemical plasma parameters in rats during intravenous injection of magnetite nanopowder].

Nanotechnology is now recognized as a priority area of researches. Despite its rapid development, the literature contains a paucity of evidence for the effect of nanoparticles on the biochemical plasma parameters of experimental animals. This paper determines the biochemical parameters reflecting the functional state of the rat vital organs. Intravenous administration of a standardized Fe3O4 nanopowder solution has shown reversible changes in the biochemical parameter of plasma.