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Shah K J - - 1977
Fifteen 7-substituted 4-hydroxyquinoline-3-carboxylic acids have been designed to minimize covariance between the physicochemical substituent parameters: pi, MR, and sigmap. The molecules have been synthesized and evaluated for their ability to inhibit the respiration of Ehrlich ascites cells as a whole cell model and for their ability to inhibit malate dehydrogenase ...
Kallio A - - 1977
1. Ehrlich ascites-carcinoma cells contained relatively high concentrations of spermidine and spermine, but the putrescine content of the washed cells was less than 10% of that of higher polyamines. 2. Ascites-tumour cells likewise exhibited high activities of L-ornithine decarboxylase (EC 4.1.1.17), S-adenosyl-L-methionine decarboxylase (EC 4.1.1.50), spermidine synthase (EC 2.5.1.16) and ...
Bellv? A R - - 1977
A procedure is described which permits the isolation from the prepuberal mouse testis of highly purified populations of primitive type A spermatogonia, type A spermatogonia, type B spermatogonia, preleptotene primary spermatocytes, leptotene and zygotene primary spermatocytes, pachytene primary spermatocytes and Sertoli cells. The successful isolation of these prepuberal cell types ...
Jones G E - - 1977
The cistron that codes for L-asparaginase I in Saccharomyces cerevisiae (aspl) is not genetically linked to either of the cistrons coding for expression of asparaginase II (asp2 and asp3). Cells containing different combinations of theses enzymes grow at different rates in media in which L-asparagine or D-asparagine is the only ...
Gasic G J - - 1977
The platelet aggregating principle of two mouse ascites tumors and of their cell-free supernatants released spontaneously has been studied. It was found that the principle disappeared from the cells after trypsin digestion and that part of it was recovered in the cell-free trypsinate. Digested cells regenerated the principle during subsequent ...
Bichel P - - 1977
The variation in the DNA distribution in the JB-1 and the Lla2 ascites tumour was investigated by means of flow microfluorometry (FMF) in the plateau stage and during the initiation of the regenerative growth induced by percutaneous aspiration. The study showed that a considerable influx of cells with G1DNA content ...
Shulman A - - 1977
(1)Fully coordinated 1,10-phenanthroline and 2,2'-bipyridine chelates of Ru(II) are lethal in vitro to cultured and ascites P388 mouse lymphocytic leukaemic cells; 1,10-phenanthroline chelates are generally more potent than corresponding 2,2'-bipyridine compounds, and mixed-ligand (acetylacetonato) monovalent chelates of both series are more active than the corresponding identical-ligand divalent chelates. Lethal potency ...
Heppel L A - - 1977
Various agents alter mammalian cells so that they rapidly become nonspecifically permeable to substances that ordinarily do not penetrate intact cells. Thus, toluene renders liver cells permeable to nucleotides and macromolecules. Tween 80 and Tween 60 act on similar fashion, and the effect is reversible. Dextran sulfate reversibly alters the ...
Matousek J - - 1977
Bull seminal vesicle ribonuclease, when added in vitro to the suspension of ascitic leukaemic cells EL-4 and BP-8 for 2 hours at 37 degrees C and then transplanted to the abdominal cavities of mice, inhibitied the proliferation of these cells in vivo. When the temperature of the medium was decreased ...
DeBernardo E - - 1977
Investigations on the spontaneous release of 51Cr from the EL-4 ascitic lymphoma showed that daily rhythmic changes can be correlated with the dominance of certain cell types in the population. A generation time of 9.8 h, an average doubling time of 32 h, and an 'appearance cycle' of 96 h ...
Eisen H - - 1977
The ability of Plasmodium chabaudi and P. yoelii to bind to Friend erythroleukemia cells in vitro was examined. Extensive binding of P. yoelii and weaker binding of P. chabaudi was observed. Binding to mouse fibroblasts was not seen, although there was some binding to cells of a mouse mastocytoma. The ...
Anghileri L J - - 1976
The release of a part of the cell coat of Ehrlich ascites cells by chelation with ethylenediamine-tetraacetic acid modifies significatively the uptake of various radioactive molecules. This phenomenon seems to be related to a change in the permeabililty of the cell membrane. The chemical analyses of the released material appear ...
Marggraf W D - - 1976
32P-Labeled phospholipids with specific activities up to 400 mCi/mmole as well as [32P]CDP-choline were prepared by cultivation of mouse fibroblasts or mouse Ehrlich ascites cells in the presence of [32P]orthophosphate. The method was also used to prepare [methyl-3H]choline-labeled glycerophospholipids from [3H]choline. The yields and the specific activities of the phospholipids ...
Spencer T L - - 1976
The transport and oxidation of succinate by functionally intact Ehrlich ascites-tumour cells was investigated. On the basis of pH dependence and inhibitor sensitivity it was concluded that succinate may be transported across the cell membrane by the organic anion carrier system. Thus the ability of isolated Ehrlich cells to oxidize ...
Goessens G - - 1976
Nucleoli were studied in chick fibroblasts cultured in vitro, under normal or under experimental conditions, and in several mammalian cell types in vivo. All these cells frequently contain nucleoli with fibrillar centres. The nucleolar fibrillar centres are composed of fibrous material of low electron density and are always intimately associated ...
Frimmer M - - 1976
Leucocidin, one of the cytotoxic principles of Pseudomonas aeruginosa induces potassium loss and swelling in isolated hepatocytes and in AS-30D ascites hepatoma cells in a dose and time dependent manner. Hepatoma cells are more sensitive than normal hepatocytes. As shown by scanning electron microscopy the volume increase of both types ...
McCoy G D - - 1976
Exposure of Ehrlich ascites tumor cells to the polyanion dextran sulfate altered the permeability of the plasma membrane resulting in decreased glycolysis and respiration, enhanced permeability to Rb+ and adenosine 5'-triphosphate, and increased staining by erythrosin B. The inhibition of respiration was reversed by the addition of inorganic phosphate, whereas ...
Tanino T - - 1976
Components on the surface of MM2 ascites mammary carcinoma cells induce agglutination factors in the serum of syngeneic host C3H/He mice, and bind the factors in vitro. These components have been classified into three groups: MM2-specific substances, mammary tumor virus (MTV)-associated substances and tumor-associated embryonic materials. The substances contained saccharide ...
Giraldi T - - 1976
Equinatoxin, a highly basic protein extracted from Actinia equina, causes an increase in the survival time of mice bearing the ascitic form of Ehrlich carcinoma, whereas it has no effect on L1210 leukaemia. When tested for in vitro cytotoxicity by the dye exclusion test, it shows a potent activity on ...
Jimenez A - - 1976
The effects of eighteen compounds obtained from bulbs of the Amaryllidaceae family were tested on (a) animal cell growth, (b) DNA, RNA and protein synthesis by intact cells and (c) protein synthesis in cell-free systems. Dihydrolycorine, haemanthamine, lycorine, narciclasine, pretazettine and pseudolycorine halted HeLa cell growth at 10(-1) mM or ...
Coats E A - - 1976
Seven para-substituted [phenylglyoxal bis(4-methyl-3-thiosemicarbazone)]copper (II) chelates (12-18) have been designed, synthesized, and tested for their ability to inhibit the respiration of rat liver slices as a normal cell model and Ehrlich ascites cells as a tumor cell model. Relationships between chemical structure and respiratory inhibition are described on a quantitative ...
Anglhileri L J - - 1976
The effects of trypsin and EDTA on the cell coat of ascites tumor cells were studied by means of biochemical and electron microscopy techniques. EDTA seems to release, by chelation of the Ca2+-bridges, an outer layer of glycoproteins of presumably exogenous origin. On the contrary, trypsin produces a deeper enzymic ...
Bichel P - - 1975
In most experimental ascites tumours the growth rate decreases with increasing age and cell number. This decrease is caused by a prolongation of the cell cycle and an increasing accumulation of non-cycling cells in resting (or quiescent) G1 and G2 compartments. In cell-free ascitic fluid from the JB-1 ascites tumour ...
Kanai K - - 1975
AH-66 rat ascites hepatoma cells incorporated [14C]leucine into the AFP fraction. In a cell-free system, hepatoma ribosomes were found to be active in AFP synthesis whereas the supernatant fraction from hepatoma had no specific effect on AFP production. The amount of [14C]leucine incorporated in AFP by membrane-bound polysomes was 20 ...
De Paermentier F - - 1975
Chick embryo fibroblasts cultivated in vitro and Ehrlich ascites tumor cells (in vivo or in vitro) have been treated with amphotericin B. Cell multiplication is strongly inhibited. Large clear zones appear in the fibroblast nucleoi (phase-contrast and electron-microscope observations). Many treated fibroblasts and tumour cells have a high DNA content ...
Kaneko I - - 1975
A simple quantitative assay method was developed for the agglutination of rat ascites hepatoma cells mediated by Concanavalin A or Ricinus communis agglutinin. This method was based on the principle that the turbidity of a cell suspension is proportional to the sum of the cross-sectional area of cells and aggregatesmas ...
Peirce K - - 1975
1. Cyano [57 Co] cobalamin bound to murine transcobalamin, associates with Ehrlich ascites carcinoma cells. Association was found to be dependent on temperature, and to require between 7.2 - 10-5 and 2 - 10-4 M ionized calcium. 2. Association was blocked by vinblastine and colchicine, but not cytochalasin, suggesting that ...
Balázs A - - 1975
Ascitic cells in the logarithmic growth phase increase the accumulation of glycogen particles in the course of explantation into suspension culture, probably due to the increasing arrest of glycogenolytic enzymes. At this age, a part of the cells are capable of restitution by exopinocytosis of the glycogen-containing vacuoles ia formation ...
Anghileri L J - - 1975
Calcium concentration in intra- and extracellular fluid from Ehrlich ascites tumor cells has been studied. The higher content of calcium in the outer cell fluid appears as a possible factor determining the behavior of the cell membrane. While in the cytoplasm macromolecular compounds such as lipo- and nucleoproteins seem to ...
Chou T C - - 1975
The selectivity of action of 1-beta-D-arabinofuranosylcytosine (ara-C) against leukemic cells was studied in vivo. Dynamic state tissue levels of ara-C and of its mono-, di-, and triphosphate (ara-CTP) were measured in L1210 leukemic cells and in C57BL x DBA/2 F1 host tissues at different times after various doses of the ...
Sen G C - - 1975
We reported earlier that in cell extracts that were prepared from interferon-treated Ehrlich ascites tumor cells and preincubated and passed through Sephadex G-25 (S60INT), the translation of exogenous mRNA (viral and host) was impaired and the impairment could be overcome to a large extent by adding a crude tRNA preparation ...
Spirer Z - - 1975
The influence of Tuftsin, the synthetic phagocytosis-stimulating tetrapeptide (L-threonyl-L-lysyl-L-prolyl-L-arginine), on the nitrous blue tetrazolium (NBT) reduction by human polymorphonuclear leukocytes was investigated. It was found that this substance increases the NBT reduction by approximately as much as endotoxin. Other tetrapeptides do not share this property. When Tuftsin analogs are added ...
Kudo K - - 1974
A substance capable of promoting tumour cell aggregation was released from rat ascites hepatoma cell (possibly from the cell surface) kept in Hanks' balanced salt solution (free of calcium and magnesium) in the cold, and then partially purified by chromatography with DEAE-Sephadex and gel filtration with Bio-gel. The thermostable substance ...
Schendel D J - - 1974
H-2 congenic mouse strains were tested in vitro to investigate the genetic control of cell-mediated lympholysis (CML). Combinations were selected such that differences in various segments of H-2 could be examined for their ability to stimulate production of effector cells and to serve as targets for lysis. Particular emphasis was ...
Penttila A - - 1974
The present study indicates that extracellular acidosis protects Ehrlich ascites tumor cells and rat kidney cortex cells against injury from anoxia. Parameters measured included cell potassium, adenosine 5'-triphosphate, and uptake of vital dyes. Cells survived longer at a pH of 5.6 to 6.5 than at a pH of 7.4; pH ...
Brenneman D E - - 1974
Much of the lipid present in the ascites plasma in which Ehrlich cells grow is contained in very low density lipoproteins (VLDL). Chemical measurements indicated that triglycerides were taken up by the cells during in vitro incubation with ascites VLDL. When tracer amounts of radioactive triolein were incorporated into the ...
Waterson J R - - 1974
This study explored the possibility whether an altered cysteinyl-tRNA synthetase might lead to the faulty regulation of cyst(e)ine levels in cystinotic cells. This hypotheses is attractive, since amino acid activation is important in the regulation of amino acid metabolism in microorganisms. By using cultured fibroblasts from patients with cystinosis, those ...
Okada Y - - 1974
When Ehrlich ascites tumor cells fused with UV-inactivated HVJ (Sendai virus) were cultured, the viral envelope antigens, which had been integrated at random into the cell membranes, accumulated at one site on the fused cell. The site showed a specific structure, namely, a projection of the cytoplasm from the spherical ...
Anghileri L J - - 1974
The metabolism of acid mucopolysaccharides in Novikoff hepatoma and in hepatoma BW7756 was studied using the precursors -35S-sulfate, -H-glucosamine and -14C-galactosamine. There is an active formation of sulfated mucopolysaccharides at the mitochondria and cell membrane level. Hepatoma cells synthesize heparin to a lower rate than liver cells. In ascitic as ...
van Rijn H - - 1974
The ability of N(6), O(2)'-dibutyryl cyclic AMP (DBcAMP) to regulate a number of metabolic events in four lines of cultured rat hepatomas has been examined. Although dexamethasone induces tyrosine transaminase in all four lines, DBcAMP induces this enzyme normally only in H35 cells. A slight increase in transaminase activity was ...
Feldmann M - - 1972
Tissue cultures with two compartments, separated by a cell impermeable nuclepore membrane (1 micro pore size), were used to investigate the mechanism of T-B lymphocyte cooperation. It was found that collaboration was as effective when the T and B lymphocyte populations were separated by the membrane as when they were ...
Phillips S G - - 1971
Nucleoli of cultured Chinese hamster or mouse cells in early passages had a loosely reticular substructure. Within the reticulum small, irregularly shaped, light fibrillar zones occurred which were contiguous with denser fibrillar zones. These denser zones appeared to be connected in some places to the particulate material which composed the ...
Belkin, Morris
When malignant cells, animal and human, were exposed in vitro to solutions of heavy metals or other selected compounds, three types of cell blebs were produced: (1) acentric blebs, arising from one side of the cell, e. g., by chlormerodrin, meralluride sodium, mercuric chloride; (2) symmetrical blebs; which completely enveloped ...
Housman, David
An RNA sedimenting at 10 S, with a molecular weight of 2.3 × 105, was isolated from rabbit reticylocyte polyribosomes. When this RNA is added to a cell-free extract from Krebs II ascites cells, both α and β chains of rabbit hemoglobin are synthesized; β chains are made in about ...
Bacchetti S - - 1969
The lethal and inhibitory effects of actinomycin D (Act D) on asynchronous and synchronized populations of mouse L-cells have been studied. It has been shown that the survival curve of populations in the logarithmic phase of growth can be approximated by two exponential survival curves corresponding to a sensitive and ...
Khmelevskiy, V. I.
The anti-mitotic activity of N-acetylcolchamine on Ehrlich ascites cancer cells has been studied in vivo in mice. It has been established that N-acetylcolchamine is an inhibitor of mitosis which, like colchicine, is able to block cell division at the stage of metaphase. Since N-acetylcolchamine is more readily available than colchicine, ...
Martin W J - - 1968
In this series of papers it has been shown that the immune response of mice to sheep erythrocytes requires the participation of two classes of lymphoid cells. Thymus-derived cells initially react with antigen and then interact with another class of cells, the antibody-forming cell precursors, to cause their differentiation to ...
Kellogg D S DS - - 1968
During 35 months of selective in vitro cultivation, Neisseria gonorrhoeae cells retained their virulence for humans and were shown to be closely related to a particular colonial morphology. Saline-autoagglutinability was the only other characteristic distinguishing virulent from avirulent cells. Human responses to challenge with cells of the different colonial types ...
Mishin, L. N.
Work was carried out on the development of a complex of equipment which is required for mastering of the suspended cultivation of cells in conformity with the conditions at an industrial cultivation laboratory.
Krouse H R - - 1968
A pulsed feeding technique was used during studies of sulfite reduction by Salmonella heidelberg in order to realize large percentages of SO(3) (=) conversion while simultaneously maintaining a reasonably stable cell population. As a consequence, much data for conventional kinetic and sulfur isotope fractionation computations were obtained in any one ...
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