A Novel Technique for Preparation, Staining, and Visualization of Tissue with Metal Implants and Extraskeletal Calcification Areas.

The aim of the study was to evaluate the efficacy of a novel technique for preparation, staining, and visualization of tissues containing extra-skeletal mineralization areas, all-metal implants or their prototypes for their subsequent examination using scanning electron microscopy in the backscattered electron mode. MATERIALS AND METHODS: After fixation in 10% formalin (24 h), the biomaterial (a titanium nickelide plate with the surrounding tissues after subcutaneous implantation, patented titanium alloy plates with the surrounding tissues after cranioplasty, primary and secondary calcified atherosclerotic plaques) were fixed with 1% osmium tetroxide (12 h) and then stained with 2% aqueous solution of osmium tetroxide (48 h). The samples were further stained with 2% alcoholic uranyl acetate (5 h), dehydrated with isopropanol (5 h) and acetone (1 h), impregnated with a mixture of acetone and epoxy resin Epon (1:1, 6 h) and then embedded into a fresh portion of epoxy resin (24 h), which was followed by polymerization at 60°C. After grinding and polishing, epoxy blocks were counterstained with lead citrate (7 min) and sputter-coated with carbon, then the samples were visualized by scanning electron microscopy in the backscattered electron mode. The elemental composition was studied using X-ray microanalysis. RESULTS: The developed technique allows obtaining high-quality images at five thousand-fold magnifications, provides the possibility to identify the shape and structure of intact metal and mineral inclusions, and to type the surrounding cells, distinguishing mesenchymal and immunocompetent cells by shape and cytoplasmic content. Apart from connective tissue capsule thickness and leukocyte infiltration, this technique makes it possible to estimate the number and area of newly formed small-caliber vessels representing a surrogate marker of inflammation. CONCLUSION: The proposed technique provides the possibility to investigate adequately the structure of samples when their sectioning is impossible or significantly complicated, with image quality remarkably higher than that obtained by light microscopy.

[Comparative study of vasa vasorum and neointima in conduits for coronary artery bypass grafting]. / Sravnitel'noe izuchenie vasa vasorum i neointimy v konduitakh dlia koronarnogo shuntirovaniia.

AIM: This study was undertaken to investigate the preoperative incidence and severity of intimal hypertrophy, as well as the level of blood supply of arterial and venous conduits for coronary artery bypass grafting. MATERIAL AND METHODS: Segments of the internal thoracic artery and great saphenous vein (n=13) were harvested pairwise during coronary artery bypass grafting and were then visualized by scanning electron microscopy in back-scattered electrons. The analysis of the incidence and thickness of intimal hypertrophy, as well as the calculation of the number and the area of the vasa vasorum were performed using the programme ImageJ. RESULTS: Intimal hypertrophy was more characteristic for the great saphenous vein as compared with the internal thoracic artery (9/13 (69.2%) and 7/13 (55.8%), respectively), although this difference did not reach statistical significance. The maximal-to-minimal neointimal thickness ratio correlated with the percentage of stenosis (r=0.875, p<0.0001), the area (r=0.45, p=0.023) and the number (r=0.47, p=0.015) of the vasa vasorum in the conduits, thus confirming the hypothesis on possible participation of these vessels in the development of intimal hypertrophy, with the area of the vasa vasorum being greater in the vessels with >10% stenosis (p=0.051). The number of the vasa vasorum in the great saphenous vein exceeded that in the internal thoracic artery (p=0.0005), with this difference remaining significant after adjustment for the area of the adventitia (p=0.027). The number of the vasa vasorum per the percentage of stenosis in the great saphenous vein also exceeded that in the internal thoracic artery (p=0.039) and more strongly correlated with intimal hypertrophy in the great saphenous vein as compared with that in the internal thoracic artery (r=0.53 and r=0.27, respectively). CONCLUSION: Intimal hypertrophy correlates with the area and number of the vasa vasorum in conduits. The great saphenous vein is characterised by a larger number and higher density of the vasa vasorum as compared with the internal thoracic artery. The number of the vasa vasorum is correlated with stenosis of the great saphenous vein more closely than with stenosis of the internal thoracic artery. This may be suggestive of significant predisposition of the great saphenous vein to the onset of adventitial inflammation followed by the development of intimal hypertrophy.

[Clinical x-ray characteristics of recurrent tuberculosis of the bronchopulmonary system in patients with chronic respiratory diseases]. / Kliniko-rentgenologicheskie osobennosti retsidivov tuberkuleza bronkholegochnoi sistemy u bol'nykh s khronicheskimi zabolevaniiami organov dykhaniia.

X-ray and clinical features of tuberculosis combined with lingering pneumonia were studied in 110 patients of the 7th group of dispensary registration suffering from chronic diseases of the respiratory organs. Tuberculosis recurrences in this group of patients had a torpid course, specific changes were slowly reversed, noticeable fibrosis was formed on their site. Thorough x-ray tomographic investigation not only of the pneumonia zone but also of the zone of posttubercular changes was conducted at the onset and end of pneumonia therapy to exclude tuberculosis reactivation. Frequent exacerbations of chronic diseases of the respiratory organs including complications in the form of lingering pneumonia in patients with posttubercular changes can mask early stages of tuberculosis reactivation.

[Biochemical polymorphism in the northern fur seal, Callorhinus usinus, from 3 regions of the northwestern part of the Pacific Ocean]. / Biokhimicheskii polimorfizm severnogo morskogo kotika Callorhinus ursinus iz trekh raionov severno-zapadnoi chasti Tikhogo okeana.

Polymorphism for the number of the blood proteins (transferrin, alkaline phosphatase, haptoglobin, plasma esterase and erythrocyte esterase) have been exposed by means of starch gel electrophoresis of northern fur seal Callorhinus ursinus from three regions: Pelagic of Commander Islands (n = 164), Rockery of Robben Island (Sakhalin population, n = 308), winter todder region to the east of Honshu Island (n = 110). The reliable differences have been exposed between fur seals of the Commander and Sakhalin populations by the gene frequencies Tf and Es pl. Fur seals from winter todder region turned out to be closer to Commander population, that to the Robben one. However, originality of gene frequencies of locus Ap (alkaline phosphatase), revealed from the todder region animals, is difficult to explain by the mixture of the Commander and Robben population only. Perhaps, this originality is caused by the influence of Pribylov population. It is established that hemoglobin of northern fur seal consists of two components (Hb I + Hb II). Individual variability of hemoglobin results in the variation of the colour intensity of the "slow" component (Hb II).