[Type 3 membranoproliferative glomerulonephritis: an unusual variety of well-known pathology].

Light microscopy, immunohistochemistry, and submiscroscopy were used to study a renal biopsy specimen obtained from a 51-year-old old male suffering from type 3 membranoproliferative glomerulonephritis (MPGN-3) concurrent with HCV infection. Along with the signs characteristic of MPGN-3 (glomerulosclerosis; crescents; subendothelial and subepithelial deposits; proliferation of mesangial and endothelial cells), abundant pro- and myelocytes were found in the glomerular capillary lumens with active granular formation in the Golgi apparatus and with granular exocytosis into the glomerular basement membrane. Apoptotic elements were recorded among both glomerular and tubular epithelial cells.

[Plasma membrane focal defects in structurally normal cells].

The technique of perfusion fixation through the rat kidney vasculature was modified to ensure the highest possible level of cell preservation close to that under in vivo conditions. Electron microscopic analysis of the tissue specimens treated in such a way revealed local defects of the plasma membrane in a number of cells than that otherwise looked normal. These findings together with the evidence for reparability of such defects and some data on the purely artificial nature of certain alterations should be taken into consideration in order to avoid misinterpretations while diagnosing the biopsy specimens.

[Renal tubular epithelocytic changes in hypercysteinemia and experimental chronic renal failure].

One group of adult male Wistar rats received DL-homocysteine, 13.4 mg/kg body weight every day (an HC-group) while the rats underwent subtotal nephrectomy (a SN-group) and were killed 3 weeks later. Both light and electron microscopies were used to analyze obtained renal specimens. A total loss of the brush border in some proximal tubular (PT) cells and an increase of autophagosomes and emergence of the loci of disorganized cytoplasm were observed in the HC-group, while in the SN-group there was a significant increase in the number and size of secondary lysosomes and of foci of the cytoplasmic disorganization.

[Intensive drying of grids after lead citrate staining lowers precipitate contamination on the surface of ultrathin sections]. / Intensivnoe vysushivanie posle kontrastirovaniia protivodeistvuet vypadeniiu osadkov na poverkhnosti ul'tratonkikh srezov.

Two techniques are proposed to minimize precipitate contamination of ultrathin sections after lead citrate staining. According to the first one, stained and washed grids are placed, sections downward, on a stack of filter papers. The second one involves a consecutive washing of grids with distilled water, 96% ethanol, and n-hexane. Both techniques are equally efficient; the former being simpler in processing, while the latter is superior in the reproducibility of results.

Adsorption of glucoamylase from Asp. awamori X-100/D27 on cell walls.

Upon secretion, the major form of glucoamylase from Asp. awamori adsorbs on fungal cell walls. Its substrate binding site showing affinity for alpha-1-4 and alpha-1-6 wall glucans is responsible for adsorption. The minor form in which this site is absent has no sorption ability for cell walls.

[Fungus imitators in the newborn brain]. / Imitatory gribov v golovnom mozge u novorozhdennykh.

Morphology of the basophilic fibers erroneously considered by some authors as the fungus mycelium found in 4 newborns with periventricular leukomalacia is studied at the light- and electron microscopic level. Differential diagnosis between fungi and these structures which, in the authors opinion, are the damaged non-myelinated axons, including those with mineralization, is presented.

[Brain cryptococcosis in HIV infection]. / Kriptokokkoz golovnogo mozga pri VICh-infektsii.

A 30-year-old female with HIV-infection (AIDS-stage) died with generalized, including meningoencephalitis, infection. Fungi found in the brain were identified as Cryptococcus neoformans. Fungal cells were also found in the lungs and in the necrotic phlegmon of soft tissue i. e. there was a generalized Cryptococcus infection.

[The interaction of neutrophilic granulocytes with Candida albicans fungi in the formation of mycotic foci under conditions of immunodepression]. / Vzaimodeistvie neitrofil'nykh granulotsitov s gribami Candida albicans pri formirovanii mikoticheskikh ochagov v usloviiakh immunodepressii.

In the electron-microscopic study of the interaction of neutrophil granulocytes with the fungal species C. albicans in the process of the formation of mycotic foci in mice under the conditions of cyclophosphamide-induced immunosuppression, mouse leukocytes have been found to retain their capacity for migration to the focus of inflammation and for the phagocytosis of fungal cells. At the same time the fungicidal activity of leukocytes is decreased, which is manifested by the prevalence of viable fungal cells with the partially digested cell wall in the cytoplasm of leukocytes.

[Histological, histochemical and ultrastructural analyses of the development of candidal granulomas]. / Gistologicheskii, gistokhimicheskii i ul'trastrukturnyi analiz razvitiia kandidoznykh granulem.

The development of Candida granulomas was studied in experimental model using histological, enzyme histochemical and electron microscopic methods. The granulomatous response first appeared 3-5 days after injection of heat-killed Candida albicans blastospores in hepatic portal system of mice. This response reached maximum at 10-12 days, when a significant part of hepatic parenchyma was involved, regressing thereafter. In the course of maturation, the granulomas, initially consisting of loose aggregates of monocytes and immature macrophages, were transformed into compact structures with the predominance of mature epithelioid cells with typical enzyme histochemical and fine structural features. In regressing granulomas, the accumulation of immature cells was again seen. Long-term administration of cyclophosphamide suppressed the development of Candida hepatic granulomas.

[Cytohistologic and ultrastructural characteristics of the early stages of the interaction of Candida with epitheliocytes]. / Tsitogistologicheskie i ul'trastrukturnye osobennosti rannykh étapov vazimodeistviia gribov Candida s épiteliotsitami.

Cyto-histological and ultrastructural features of the initial stages of the interaction between Candida cells and epitheliocytes of human and animal mucous membranes were studied in vitro and in vivo. The population of epitheliocytes is heterogeneous in its adhesive properties, 15-20% of cells being several times more adhesive than the rest of the population. Within an individual epitheliocyte the adhesion of blastospores was nonuniform, the majority of the latter attaching to the periphery of the cell and to the intercellular boundaries. This was found in cytological smears, histological film preparations and in SEM micrographs, and was also confirmed by the results of morphometric analysis. Ultrastructural analysis has revealed two phases of the interaction between Candida blastospores and epitheliocytes during adhesion, as well as the cytological effect of the fungal cells.

[Submicroscopic study of adenohypophyseal cells with the hypophysis incubated in a hypertonic solution. I. The distribution of acid phosphatase, thiamine pyrophosphatase and arylsulfatase activities]. / Submikroskopicheskoe issledovanie adenogipofizarnykh kletok pri inkubatsii gipobiza v gipertonicheskom rastvore. I. Raspredelenie aktivnostei kisloi fosfataze, tiaminpirofosfatazy i arilsul'fatazy.

In the rat adenohypophyseal mammotrophs and somatotrophs, activities of acid phosphatase, thiamine pyrophosphatase and aryl sulphatase were defined after the incubation of the pituitary gland in the medium containing 1.65 M sucrose. Following 60--120 minutes of the incubation the above enzymes were found, in addition to their usual sites, in all cisternae of the Golgi apparatus and the rough endoplasmic reticulum as well as within the perinuclear cisternae. The mechanism of the above alterations is discussed, and a suggestion is put forward that the emergence of enzymatic activities in the above structures may reflect their biogenetic pathways in the cell.

[Submicroscopic study of adenohypophyseal cells with the hypophysis incubated in a hypertonic solution. II. Differential analysis of the intracellular distribution of arylsulfatase and thiamine pyrophosphatase within a single cell]. / Submikroskopicheskoe issledovanie adenogipofizarnykh kletok pri inkubatsii gipofiza v gipertonicheskom rastvore. II. Differentirovannyi analiz vnutrikletochnogo raspredeleniia arilsul'fatazy i tiaminpirofosfatazy v predelakh odnoi kletki.

In the rat pituitary gland exposed to an hour incubation in the medium containing 1.65 M sucrose activities of aryl sulphatase (AS) and thiamine pyrophosphatase (TPP) were successively defined within a single specimen. After the detection and registration of both enzyme activities with the electron microscope ultrathin sections were processed with 50% H2SO4 resulting in the complete removal of the reaction products for TPP. In the mammotrophs and somatotrophs, cisternae of the Golgi apparatus and rough endoplasmic reticulum showed either AS, or TTP or both the enzymatic activities. In the latter case the two enzymes could be restricted to a single cistern.

[Spatial distribution of thiamine pyrophosphatase and arylsulfatase activities in the area of the Golgi apparatus of the adenohypophyseal secretory cells in the white rat]. / Prostranstvennoe raspredelenie aktivnostei tiaminpirofosfatazy i arilsul'fatazy v oblasti apparate Gol'dzhi sekretornykh kletok adenogipofiza beloi krysy.

Specimens of albino rat pituitary glands were processed consecutively for demonstration of thiamine pyrophosphatase (TPPase) and aryl sulfatase (ArSase) activities. To differentiate between the structures associated with each particular enzyme studied within a single cell, either somatotroph or mammotroph, ultrathin sections were exposed for 2 minutes to 2--50% H2SO4 which removed the reaction products for TPPase rather than those for ArSase. The comparative study of pairs of micrographs of the same area taken before and after the etching with H2SO4 has shown TPPase and ArSase to reside in the Golgi apparatus and GERL system, respectively. Transitional elements have also been discovered, thus supporting the idea that GERL may be a derivative of the Golgi apparatus.

[Unusual structures in the epithelium of the mammary glands of white rats]. / Neobychny struktury v épitelii molochnykh zhelez belykh krys.

Ribbon-like structures derived from the rough endoplasmic reticulum have been revealed in the mammary gland epithelium at different physiological state. Some of these structures were located lying free in the background cytoplasm, while others penetrated cellular organelles and, sometimes, intracellular borders, passing from one cell into the cytoplasm of neighbouring cells. The genesis and functional significance of these structures is discussed.

[Submicroscopic changes in the mammary gland epithelium of white rats during chronic administration of high doses of estrogen]. / Submikroskopicheskoe izmeneniia v épitelii molochnykh zhelez belykh krys pri dlitel'nom vvedenii vysokikh doz éstrogena.

Ultrastructural alterations of female albino rat mammary glands in normal estrous cycle as well as in lactation, postlactation involution caused by weaning of sucklings from the nursing dams, and after administration of estrogen (synestrol) in a daily dose of 0.1 mg per 100 g body weight were studied. Particular attention was given to histochemical and morphometrical analys is of the secretory and vacuolar apparatus of the epithelial cells. A significant increase in the number of secretory granules in estrus as compared to that in diestrus accompanied by the reverse relationships in primary lysosome (small coated vesicles) count was observed. Similar relationships between the above parameters were found when the mammary glands of the lactating animals and those from the dams with their sucklings weaned were compared. The abundant primary and secondary lysosomes, autophagosomes, and heterophagosomes as well as some Golgi lamellae and smooth cisternae of endoplasmic reticulum filled with acid phosphatase were often observed in the epithelial cells of the involutary mammary glands, indicating the activation of the vacuolar apparatus. In synestrol-treated animals a gradual decrease in both secretory and catabolic activities occurred after transient successive increase of these two activities. The possible role of the relationship between the secretory and catabolic activities of the epithelial cells during mammary gland tumorogenesis is considered.

[Ultrastructural changes in the mammary glands of white rats during the estrus cycle]. / Ul'trastrukturnye izmeneniia sekretornykh kletok molochnoi zhelezy belykh krys vo vremia éstral'nogo tsikla.

Secretory granules of milk protein were found in the apical cytoplasm of some ductal cells in the mammary gland of non-lactating albino rats. During the estrous period, the diestrous phase, the number of "coated" vesicles increased essentially. Some of the "coated" vesicles contained secretory granules and granular debris. The functional relationship of the "coated" vesicles to lysosomes and to some other cytoplasmic structures is discussed. The results suggest that during the estrous phase formation and release of secretory products prevail, whereas at the diestrous the process of their removal and destruction is predominant.