Renal cell tumours in mice: electron microscopy versus immunohistochemistry.

15 renal cell tumours induced in CBA male mice by 1,2-dimethylhydrazine were studied electronmicroscopically (EM). All these tumours earlier were investigated histochemically and immunohistochemically with the use of gamma-glutamyltranspeptidase (GGT) as a marker of the proximal tubules and antigen A6 as a marker of distal tubules and/or collecting ducts. One of the tumours was GGT-positive and antigen A6-negative and ultrastructurally well developed brush border was found. This correlation between immunohistochemistry and EM data allowed to conclude that the site of origin of this tumour were the cells of the proximal tubules. All other tumours were GGT-negative and antigen A6-positive, i.e. the development of these tumours from the distal tubules (and not from the proximal tubules) could be suspected. However in 5 of these neoplasms reduced brush border was found. Microvilli were of a smaller size than in normal proximal tubules and were frequently located not on the apical cell surface but in the narrow spaces between two cells. Invaginations and apical vesicles typical for the normal proximal tubules were also found in some tumour cells. EM and immunohistochemical data combined allow to suggest the origin of these tumours from the common precursor cell capable of differentiation, in the course of tumour progression, into the cells with properties of proximal and/or distal tubules.

[Formation and accumulation of myelin bodies and other membrane structures in the arterial wall in man in atherosclerosis]. / Obrazovanie i nakoplenie mielinovykh telets i drugikh struktur v arterial'noi stenke chelovek pri ateroskleroze.

Unaltered areas and fibrolipid plaques of various human arteries were examined electronmicroscopically. Myelin bodies were found to be produced by smooth-muscle cells of the intima and media of unaltered parts of the arterial wall. The formation of myelin bodies by smooth-muscle cells significantly increases in the fibrolipid plaques. Myelin bodies are frequently located in the cytoplasm matrix of altered smooth-muscle cells, in the areas of myofilament lysis. They are also found within mytochondria and in the cystern lumina of the granular cytoplasmatic reticulum. The accumulation of membranous structures in the fibrolipid plaques results from myelin-body production by smooth-muscle cells and vacuoles and vesicules of a varying size.

[Morphological and ultrastructural characteristics of the epithelial cells of the parathyroid glands]. / Morfologicheskie i ul'trastrukturnye osobennosti épitelial'nykh kletok okoloshchitovidnykh zhelez

Histochemical and ultrastructural characteristics of the main, oxyphilic and C-cells of 50 parathyroid glands of man and 105 ones of animals (rats) is presented. Types of the structure of the structure of the parathyroid glands (compact, retiform, lobular) are identified and their morphological changes under conditions of impairment of the phosphorus-calcium metabolism are described.

[Electron microscopic detection of the proteoglycan component of the extracellular matrix in osteogenic sarcomas]. / Elektronno-mikroskopicheskoe vyiavlenie proteoglikanovogo komponenta vnekletochnogo matriksa osteogennykh sarkom.

Electron-microscopic studies in which Alcian blue was used to demonstrate proteoglycans (PG) revealed a predominance of largely undifferentiated tumor cells in two of the osteosarcomas examined; the extracellular matrix of these tumors had few PG-containing structures. Other osteosarcomas, where cells of the osteoblastic type prevailed, were found to possess PG granules on the cell surface and a rough PG network in the pericellular space. In a parosteal osteosarcoma, which contained strongly elongated fibroblast-like cells, PG formed a fine mesh both in the pericellular space and throughout the extracellular matrix. A correlation therefore exists between the ultrastructure of the PG component in the extracellular matrix of osteogenic sarcomas and the degree and direction of tumor cell differentiation.

[Distribution of collagen types I, III, IV and V in the walls of human arteries]. / Raspredelenie kollagena I, III, IV, V tipov v stenke arterii cheloveka.

Using immunofluorescence the localization of I, II, IV, V type collagen in different layers of the artery wall was established. The adventitia was shown to contain only I and III type collagen. All collagen types studied were identified in the media. The structural organization and quantity of different types of collagen were found to depend on the artery caliber. The distribution of I, III, IV, V type collagen in the aortal intima is described. The localization of athrombogenic collagen of type IV and V in the area of the endothelial basal membrane is highlighted. The authors revealed the presence of I and III type collagen in the subendothelium and the age-related increase in interstitial collagen levels in the intima which is important for predicting thrombosis in deendothelization . Employing immunoelectron microscopy, previously undescribed forms of I, III, IV, V type collagen organization into microgranular structures were ascertained.

[Mouse hepatoblastoma: comparative aspects]. / Gepatoblastoma myshei v sravnitel'nom aspekte.

The structure of 12 spontaneous hepatoblastomas found in old (average age 26.5 months) male mice is described. There were considerable strain differences in their incidence: 0.5% (1/194), 0.5% (1/194) and 5% (10/198) in strain C57B1, CBA and F1 (CBA X C57B1), respectively. This proves the importance of genetic factor the role of which in the development of human hepatoblastoma is not established so far. Mouse hepatoblastoma develops almost invariably within or adjacent to liver cell tumours (adenoma or carcinoma). There was a correlation between the incidence of liver cell tumours within a given strain treated with different doses of carcinogen but such correlation was absent in mice of different strains. Histologically and ultrastructurally, mouse hepatoblastoma corresponds to the anaplastic variant of human hepatoblastoma. As distinct from human tumour, mouse hepatoblastoma does not contain alpha-fetoprotein. One tumour was transplanted to the syngeneic host and passed 30 transplant generations retaining the structure of a primary tumour with areas of osteoid tissue and foci of squamous cell metaplasia. Mouse hepatoblastoma may be induced by carcinogens. Likewise, according to the literature, risk of hepatoblastoma is higher in children whose mothers were exposed to the potential carcinogens before or during the pregnancy.

[Diethylstilbestrol-induced uterine sarcoma in mice]. / Sarkomy matki myshei, indutsirovannye diétilstil'béstrolom.

Female mice of CBA strain received diethylstilbestrol (DES) 1 g body weight intraperitoneally. High incidence of histiocytic uterine sarcoma was observed in parents (25%), first generation (F1), descendants (10.9%), and generation F2m (through F1 males mated with females in control) (17.8%). Morphologically, tumor cells examined through light and electron microscopy were referred to as histiocyte-like elements. Half of the animals had metastases in the liver, kidneys, lungs, spleen, pineal and adrenal glands and stomach. The development of tumors in generation F2m, which was not exposed to DES, might be accounted for by "transgeneration" carcinogenesis, i.e. passage of carcinogenic effect through a generation.

[N-nitrosodiethylamine-induced changes in the liver of syrian hamster with superinvasive opistorchiasis]. / Izmeneniia v pecheni khomiachkov, indutsirovannye n-nitrozodiétilaminom pri superinvasionnom opistorkhoze.

Trematoda O. felinius-induced hepatic lesions were investigated in Syrian golden hamsters with superinvasive opistorchiasis. One hundred hamsters were divided into 4 groups: (1)--control; (2) N-nitrosodiethylamine (DENA), i.p., twice a week, 3 weeks, total dose 72 mg/kg; (3) metacercariae O. felinius, with drinking water, 3 injections per day, once in 2 weeks, and (4) metacercariae O. felinius, as in group 3, followed by DENA, as in group 2. Animals were sacrificed 12 months after the beginning of the study. No changes in the liver were found in group 2. Reddish protrusions, up to 4 cm in diameter, appeared on liver surfaces in groups 3 and 4. Group 4 featured the highest relative and absolute weights of liver as well as clusters of oval cells and cholangiocellular tubules and cholangiofibrosis (in group 3, they were less visible). Electron microscopic examination identified hepatocytes with destructive changes to plasmalemma, nucleus and cytoplasmic organelles. Also, perisinusoidal cells (Ito cells) occurred. Tumor-bearing animals showed low hepatic cytochrome P-450. It is suggested that proliferative growth in the liver was stimulated by opistorchis invasion.

[Skeletal muscle ultrastructure of untrained humans and animals after physical loading]. / Ul'trastruktura skeletnykh myshts netrenirovannykh cheloveka i zhivotnykh pri fizicheskoi nagruzke.

In non-trained mice subjected to a single and repeated swimming up to complete wearness, fibres in the skeletal muscles demonstrated certain ultrastructural alterations in their nuclei. Twenty-four and 48 h after a single swimming many muscular nuclei have only non-condensed chromatin. After repeated swimming large clumps of condensed chromatin appear in most of the muscular fibre nuclei. These nuclear changes are accompanied by segregation of separate fibrillar areas containing nuclei. Similar phenomena are also noticed in muscular fibres of non-trained people after a single physical loading. Ultrastructural changes in skeletal muscular fibres of volunteers, nonsportsmen are of individual character and depend on the degree of wearness resulting from the loading. In people subjected to the experiment and having severe fatigue (disability to work) significant shifts in submicroscopical structure of the fibrillar components were observed: in mitochondria, sarcoplasmic reticulum, T-system, contractile apparatus, etc. In this case, matrix becomes clear, lysis in mitochondrial crysts, dilatation of terminal cysterns of the sarcoplasmic reticulum and T-system tubes, destructive and regenerative processes in the contractile apparatus are observed. The data obtained demonstrate varied changes in ultrastructure of different components composing skeletal muscles of the non-trained organism subjected to physical loading.

[Ultrastructure of the proteoglycan component of the extracellular matrix in the intact mammary gland and in benign and malignant mammary gland tumors]. / Ul'trastruktura proteoglikanovogo komponenta vnekletochnogo matriksa v intaktnoi molochnoi zheleze, a takzhe v ee dobrokachestvennykh i rakovykh opukholiakh.

Proteoglycans (PG) were revealed by electron microscopy using cation dyes, Alcian blue and safranin O. In intact mammary gland of dogs, each histogenetic type of cells had its specific features in the ultrastructure of pericellular matrix proteoglycan component. A thin-stitched net, consisting of small PG granules and thin filaments has been observed in the pericellular space of secretory epithelium. A well-proportioned PG net is absent near fibroblasts and macrophages. Net-like PG structure is found in the endothelium, pericytes and adventitial cells of blood capillaries. Visual changes in PG-containing extracellular matrix are observed in the epithelium of mammary gland tumors.

[The ultrastructural localization of antigen B10 of the hepatocyte plasma membrane in mouse hepatomas]. / Ul'trastrukturnaia lokalizatsiia antigena B10 plazmaticheskoi membrany gepatotsita v gepatomakh myshi.

The ultrastructure of the murine hepatocyte plasma membrane antigen (Ag B10) was studied by immunoelectron microscopy in 5 spontaneous and 3 chemical-induced hepatomas. Ag B10 was associated with plasmalemma of bile canaliculi and membrane of microvilli as in normal liver. Sometimes it was connected with plasmalemma of lateral domain of tumor cells. The availability of Ag B10 in the matrix of bile canaliculi and within microvilli was shown.