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PubMed1991

[Proliferative processes in nerve tissue culture under the action of ethanol].

The authors describe the ultrastructure of an organotypic culture of rat brain cortex exposed to small doses of ethanol. It is shown that the small dose of alcohol (0.5% ethanol) present in the nutrient medium induced proliferation of cytoplasmic membrane structure: hyperplasia of the endoplasmic reticulum with the formation of concentrically located membranes; an increase of the number and size of mitochondria was accompanied by the appearance of the giant, atypical forms of mitochondria; proliferation of vesicular components of Golgi's laminar complex.

Animals↗
PubMed1990

[Method of total staining of monolayer cell cultures using vanadium hematoxylin].

Original method of cytological staining for monolayer cell cultures and outgrowth zone of tissue explants with vanadium hematoxylin is described. This staining method is simple, universal, reproducible and give opportunity to stain rapidly practically all cellular elements of cultivated monolayer with high degree of cytological resolution of intracellular structures (nucleus, cytoplasmic organelles etc.).

Animals↗
PubMed1990

Opsin of Calliphora peripheral photoreceptors R1-6. Homology with Drosophila Rh1 and posttranslational processing.

The rhodopsin and metarhodopsin states of two very distantly related fly species (Calliphora and Drosophila) are found to exhibit no species-specific differences in their absorbance spectra. Isolation and characterization of cDNAs encoding the major opsin of Calliphora reveal a high (86%) degree of amino acid identity with the corresponding Drosophila visual pigment. Completely conserved is the third cytoplasmic loop which displays the major structural differences with the vertebrate photopigments. Other conserved motifs are six potential phosphorylation sites in the C-terminal region of the molecule and two potential glycosylation sites in the extracellular domains at positions Asn18 and Asn194, respectively. Interestingly, unlike vertebrate visual pigments, only newly synthesized fly opsin is N-glycosylated, while the mature protein is not. The conserved structure of the cytoplasmic loops suggests that the molecular mechanism for the activation of the transduction cascade is precisely the same in Drosophila and in Calliphora. Thus, data obtained by investigating the biochemistry of rhodopsin-related processes in larger flies may be integrated with the results of genetic experiments in Drosophila into a common model of invertebrate phototransduction.

Amino Acid Sequence↗
PubMed1991

A study of modified lymphatics in the deep cortex of ruminant lymph nodes.

Ruminant lymph nodes, except when very small, were found to have a system of smooth-walled channels in the periphery of the 'deep cortical units' defined by Bélisle & Sainte-Marie (1981 a,b). Each channel originated with many 'blind' branches in the subnodular layer of the cortex and ended by joining a medullary sinus. The wall consisted of a continuous endothelial lining, a sometimes thin or discontinuous basement membrane without a basal lamina, and at least one layer of flattened reticular fibroblasts. The endothelium was higher than in most typical lymphatics, with a cytoplasmic fine structure similar to that of sinus-lining cells in the medullary sinuses. The intercellular junctions were generally long and elaborate. The lumen often contained opaque material, especially in the branches, as for initial lymphatics, as well as a few lymphocytes and an occasional nonlymphoid cell, but sinus macrophages were never seen. In some lymph nodes the lumen was crowded with lymphocytes. When small ferripolymaltose particles arrived in the node with the afferent lymph, many of them rapidly passed through the outer cortex and reached the lumen of the smooth-walled channels by way of the intercellular junctions of the endothelium. When colloidal carbon was introduced the same way, some of it also reached the channels where it accumulated in the basement membrane and in vesicles and vacuoles of the endothelium. These channels are interpreted as initial lymphatics of the same type as in other lymphoid organs rather than lymph node sinuses. They seem to play an important role for the exit of lymphocytes from the nodes and also for the passage of particulate material, including antigens, through those areas where recirculating lymphocytes arrive in the cortex.

Animals↗
PubMed1990

Effect of ketotifen on the ultrastructure of the erythrocytic stages of Plasmodium yoelii.

The effect on the morphology of Plasmodium yoelii of ketotifen treatment was different from that of chloroquine and other antimalarial drugs. Following administration of a low dosage of ketotifen, the parasite first developed a multilamellate pellicular complex which resembled a medullary sheath and then developed vacuoles and cavitations. The development of large multilamellate whorls consisting of a pellicular structure enclosing cytoplasm was the typical change which occurred.

Animals↗
PubMed1990

Balloon cell melanoma of the skin. part I: Histology, immunohistology and histochemistry.

Balloon cell melanoma of the skin was found in the left axillary region of a 60-year-old man. The tumour was very large, grew local, not forming metastases. The histological picture corresponded to a solid alveolar pattern, in some places with pseudoglandular structures. The cytoplasm of the balloon cells proved to contain lipid vacuoles and glycogen. The Masson-Fontana reaction was negative: the Warthin-Starry method gave positive results in sporadic tumour cells. The DOPA oxidase reaction was negative. Histochemistry demonstrated remarkable presence of histiocytic elements among the neoplastic cells. Reaction for the proof of alpha mannosidase was positive both in the tumour cells and in the histiocytic elements. Reaction with the NKI-C3 antibody was found to be positive in many tumour cells, the anti S-100 protein antibody less positive. Most of the cells reacted strongly positively with anticytokeratin antibody CAM 5.2. Findings of anticytokeratin antibody positive melanomas have not been published yet. Electron microscopy showed rare melanosomes in some of the neoplastic cells, making it possible to include the tumour in melanomas.

Histocytochemistry↗
PubMed1990

A novel monoclonal antibody, Mar 1, directed specifically against mononuclear phagocyte system cells in rats.

Three different monoclonal antibodies (mAb), designated Mar 1, Mar 2, and Mar 3, recognizing three distinct novel antigen molecules expressed preferentially in rat macrophages, were produced by the hybridoma technique. Binding of these mAb to isolated cells or fixed cells was detected by radioactive binding assay, immunohistochemical technique and flow cytometry. Mar 1 binds specifically to the cells constituting the mononuclear phagocyte system (MPS), but not to granulocytes nor endocytosis-positive cells from non-lymphoid tissues. Mar 2 and Mar 3 recognize both the former and the latter. The isotypes of Mar 1, Mar 2 and Mar 3 were defined as IgG1, IgG1 and IgG2b, respectively. These mAb were species specific, allo-non-specific and not cytotoxic for rat peritoneal macrophages. Immunoelectron microscopic observation demonstrated that Mar 1-3 antigens are located on both surface membrane and cytoplasmic membrane structures of peritoneal macrophages, particularly on the limiting membrane of phagocytic small vesicles and large phagosomes. Immunoprecipitation experiments demonstrated that the apparent molecular weights (MW) of the reactive antigens of Mar 1, Mar 2 and Mar 3 are 95,000, 100,000 and 55,000 and 27,000, respectively. These findings indicate that all of Mar 1-3 mAb have considerable value in the identification of rat phagocytes and that, of the three kinds of antigens detected with Mar 1-3, Mar 1 antigen is a specific marker for identification of the cells constituting the MPS and may offer the means to assess the functional capability and differentiation process of the macrophage populations.

Animals↗
PubMed1989

Localization of major potential substrates of p60v-src kinase in the plasma membrane matrix fraction.

Subcellular localization of potential substrates of a tyrosine-protein kinase, p60v-src, was analyzed by cell fractionation in combination with immunoblotting with antiphosphotyrosine antibody. In cells transformed by wild type Rous sarcoma virus, most phosphotyrosine-containing proteins were found both in plasma membranes and in a cytoplasmic matrix structure associated with plasma membranes and resistant to nonionic detergent extraction (plasma membrane matrix). A similar localization of phosphotyrosine-containing proteins was obtained in cells transformed by PRCII, Y73, or Fujinami sarcoma virus. On the other hand, in cells infected with Rous sarcoma virus mutants that encode nonmyristylated p60v-src, tyrosine phosphorylation was found mostly in proteins which were different from those identified in wild type-infected cells and were distributed to both plasma membrane and cytosolic fractions. These results suggest that most cellular substrate proteins, phosphorylation of some of which may be critical for the initiation of transformation, are present primarily in the plasma membrane-matrix structure.

Animals↗
PubMed1985

Monoclonal antibody to intermediate filaments of cytokeratin type. I. Drug studies and reactivity with cultured cells and tissue sections.

Establishment of a mouse-mouse hybridoma and partial characterization of IgM monoclonal antibody (M-04) identifying cytoplasmic filamentous structures is described. Immunofluorescence performed on a panel of various cultured human cell types as well as on frozen sections of normal and tumour tissues revealed specificity of M-04 antibody for cells of epithelial origin. Using MCF-7 cell line as a model, staining patterns of microtubules, microfilaments and M-04-target filaments in untreated cells were compared with those pretreated with Colcemid and Cytochalasin B. From both differential staining of various cell types and the results of drug studies it is concluded that monoclonal antibody M-04 binds to intermediate filaments of cytokeratin type. Furthermore, restricted expression of M-04 target determinant among epithelial tissues is suggested from the lack of reaction in stratified skin epithelium.

Animals↗
PubMed1989

[The structural bases of liver cell aging and age-related characteristics of their reactivity].

The liver of the 8-, 24-, 30- and 38-month-old Wistar male rats were studied morphometrically in the light and electron microscope under normal conditions and after bleeding and enterosorption. Under both conditions--ageing and bleeding--the hepatocyte death (apoptosis and colliquative necrosis) occurs resulting from the progression of granular and hydropic degeneration. Apoptosis develops mainly in the 1st zone and necrosis in the 3rd zone of the liver acinus this being due to the pattern of blood supply. The hepatocyte death through the apoptosis is followed by immunocompetent cell response. Compensatory processes in ageing are manifested in the hepatocyte hypertrophy this being due to the hyperplasia of cytoplasmatic structures, smooth cytoplasmic network particularly.

Adsorption↗
PubMed1989

[The ultrastructure of leptospires after freeze-etching].

The ultrastructure of three strains of leptospires, i.e. L. interrogans serovar Lai strain 017, L. biflexa serovar patoc strain Patoc I and L. illini strain 3055, were studied with the technique of freeze-etching replica. The results showed that (1) the ultrastructure of leptospires after freeze-etching are similar to that observed by means of negative staining and ultrasectioning. There are no dramatic differences among strains of leptospires studied. (2) Globular particles exposed on the resulting two inner membrane faces are asymmetrically distributed. Large areas on EF face studied with numerous globular particles, whereas the PF face had few of them. The density of globular particles varies in different parts of leptospires, from 776/microns2 to 2303/microns2. The globular particles, 14.25 +/- 2.25 nm in diameter, represent membrane proteins in outer envelope of leptospires. (3) Axial filament, 20 nm in diameter, were seen closely surrounded by a 7 nm sheath-like structure. (4) There are subcellular structures in cytoplasm of leptospires. They appear to be ribosomes, chromatins and inclusions.

Animals↗
PubMed1989

The transferrin receptor: a key function in iron metabolism.

Iron is essential to cell proliferation. Its uptake by cells requires specific binding of the major serum iron-transport protein, transferrin, to cell surface transferrin receptors, followed by endocytosis of the receptor-ligand complexes and release of iron from endosomal vesicles to the cytoplasm. The structural and functional aspects of this pathway are reviewed. Intracellular iron either serves as a substrate for the biosynthesis of haem and iron-containing proteins or is stored in ferritin deposits. Recent studies are presented which establish that iron plays an important role in the maintenance of its own homeostasis by regulating coordinately the expression of both the transferrin receptor and ferritin. The elucidation of these regulatory mechanisms may become important to the understanding of certain disorders in iron-metabolism.

Cell Division↗
PubMedDate not supplied

Fundamental study of automatic cyto-screening for uterine cancer. III. New system of automated apparatus (CYBEST) utilizing the pattern recognition method.

An investigation was carried out, both from the point of view of combining features which are considered as being of the highest reliability based on pattern analysis of the nuclear structure and cytoplasm of cells, and the complexity of the apparatus. Several features such as "ambiguity" function were extracted by mathematical and statistical processing, and these were then made the parameters of a diagnostic logic. Also, a method in which a "differential histogram" and a "threshold value" are combined was developed for segmentation of cells. It became possible to operate an automatic scanning machine at a speed of about six minutes per slide using two-stage coarse and fine scanning of a flying spot scanner. The advantage of this system is flexibility of diagnostic program logic and speed of algorithms for a determined number of cellular features. An automatic focusing system was also developed and it functions satisfactorily at high speed on a fully extended regular object slide.

Cell Nucleus↗
PubMed1986

[Establishment of a cell line from human ovarian cancer (undifferentiated carcinoma of FIGO classification) and analysis of its cell-biological characteristics and sensitivity to anticancer drugs].

A new ovarian cancer cell line has been established from the dispersed cells taken from a heterotransplanted tumor at the 6th passage in nude mice which had been serially transplanted with a primary lesion of undifferentiated carcinoma (FIGO) of the ovary. Selection of cancerous epithelioid cells was completed by the 4th passage by means of the colonial cloning method. The cell line designated TYK-nu was subcultured serially in Eagle's MEM with 10% FCS more than 100 times over 31 months at March, 1986 and was observed to produce a tumor on implantation into nude mice histologically similar to the original tumor. These cells form a monolayer in a pavement-like arrangement with polygonal cells including giant cells and reveal a lack of contact inhibition. PAS positive substance can be seen in the cytoplasm. Desmosome structure, well-developed cell organelles and glycogen granules can be found by electron microscopy. The population doubling time was about 37 hours and the plating efficiency was 13-17%. All cells were seen to be of the human karyotype on chromosomal analysis and the number of chromosome in the majority of cells was hyperdiploidy with a mode of 56 at the 6th and 84th passages. A submetacentric marker chromosome was present. Using in vitro colony assay, TYK-nu was studied for drug sensitivity to cisplatin, adriamycin, vincristine, 5-fluorouracil and etoposide, and found to be sensitive to cisplatin.

Animals↗
PubMedDate not supplied

Application of monoclonal antibodies for antigen mapping of male and female generative tissue.

With the single experiment of nature hindering the rejection of the fetus in the mother, new basic mechanisms of this immunological phenomenon can be studied. The technique of monoclonal antibodies provides a helpful tool for the study of membrane structural and cytoplasmic molecules. Hybridoma clones offer for the first time the possibility of obtaining unlimited amounts of almost pure antibodies or very high titers and of defined characteristics. The most common application with reproductive tract monoclonals are found as follows: 1) Immuno-assays; 2) Immuno-diagnostics; 3) Imaging of tumors; 4) Immuno-therapy; 5) Induction of anti-idio-types; 6) Fertility control; 7) Application in basic studies and mechanisms. The following interesting results were obtained in this area: 1) The biological role of hormones can be critically analysed by the use of highly specific non-cross-reactive monoclonal antibodies. 2) A synthetic decapeptide earlier shown by our group to be reactive with naturally occurring human iso and autosperm antibodies demonstrated to be reactive with the monoclonal antibodies Ki VII-5 presenting potentials for an investigation of sperm as target of immunological contraception for possible diagnostic and therapeutic use in immunologic infertility. 3) A specific post fertilization-development influencing antigen was identified by Menge using monoclonal antibodies. 4) Five hybridoma clones producing monoclonals to porcine zona pellucida were established, and showed a characteristic staining pattern of oocytes from human eggs, hamsters, rabbits and mice by immunofluorescence.

Abortifacient Agents, Nonsteroidal↗