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Results 501 - 550 of 812
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Kleuser B - - 1985
The relation between cellular rRNA content, as a measure of cell size, and the regulation of the cell cycle has been investigated for swiss 3T3 and the spontaneously transformed swiss 3T6 cell line. It is shown that the characteristic of percent of quiescent cells stimulated into the cell cycle versus ...
Prudovsky I A - - 1985
Resident peritoneal mouse macrophages (non-dividing differentiated cells) were fused with mouse embryo fibroblasts (cells with a limited lifespan), NIH 3T3 and C3H 10T 1/2 cells ('immortal' cell lines) and SV 3T3 cells (a malignant cell line). DNA synthesis was investigated in the resultant heterokaryons. No inhibitory effect upon the transition ...
Robinson J H - - 1985
Reproducible conditions were defined for using rates of leucine incorporation as a valid measure of rates of de novo protein synthesis in mouse 3T3 cells. Upon stimulation of quiescent cultures, rates of de novo synthesis of proteins increased and pool levels of amino acids decreased in proportion to the concentration ...
Kondo H - - 1985
The report of Carrel and Ebeling (J. Exp. Med., 34 (1921) 599-623) generally gives the impression that both serum and blood plasma from old animals inhibit cell proliferation. For confirmation of this, we examined the effects of serum from rabbits of various ages on rabbit fetal skin fibroblasts (RSF cell) ...
Jiang S D - - 1985
A simple endpoint dilution method for evaluating foetal calf serum quality is described. The test uses a series of doubling dilutions of cells on microtitre trays with the test sera added to replicate dilution series. After five to six days of incubation the cells are stained with crystal violet and ...
Briones E - - 1985
Rabbit antibodies raised against microtubule-associated protein 1 (MAP-1) from hog brain were found to crossreact with extracellular matrix components of mouse BALB/c 3T3 cell cultures. As shown by immunofluorescence microscopy of confluent cell cultures, the extracellular MAP-related antigen was located on dense fibrillar network arrays underlying and surrounding the cells. ...
Schafer I A - - 1985
We have confirmed the reports of Harper and Grove (Science, 204 (1979) 526-527), and Azzarone and Macierira-Coehlo (J. Cell Sci., 57 (1982) 177-187) that fibroblasts derived from the papillary dermis have greater in vitro growth potential and longer replicative lifespans than genomically identical fibroblasts derived from the reticular dermis. In ...
Kirk D - - 1985
We report here a unique system for tracking normal human urothelial cell migration in serum-free culture medium (HMRI-1). The key observation was that urothelial cells deposited red blood cell surface antigen on the culture dish in a remarkable pattern. Scrutiny of this pattern showed that each migrating cell left behind ...
Krause D - - 1985
The regulation of ppp(A2'p)nA-(2-5A)-dependent RNase (RNase L or RNase F) was investigated in NIH 3T3, clone 1 cells using 2-5A-binding and nuclease activity assays. Minimal levels of 2-5A-dependent RNase were detected in actively dividing clone 1 cells; these levels were independently induced by growth arrest or interferon treatment. Accordingly, levels ...
Zetterberg A - - 1985
Kinetic analysis of cellular response to serum deprivation or inhibition of protein synthesis was performed on Swiss 3T3 cells. Time-lapse cinematographic analysis of individual cells transiently exposed to serum-free medium (with or without the addition of purified growth factors) or cycloheximide enabled a detailed mapping of the magnitude and variability ...
Grupp S A - - 1985
The role of phenomena analogous to fibroblast contact inhibition in lymphocyte growth regulation is controversial, although it is clear that direct cell-cell contact is vital to immunoregulation and accessory cell function. An extract of mouse liver plasma membrane proteins, referred to as suppressive liver extract (SLE), that suppresses the growth ...
De Simone V - - 1985
The structural and biological properties of a polyomavirus mutant selected in Friend erythroleukemic cells were investigated. The growth efficiency of this mutant (PyFL78) was compared with that of the parental PyA2 strain by a growth competition assay in Friend erythroleukemic and 3T3 (or 3T6) cell lines. The results reveal that ...
Vilarem M J - - 1985
10-[Diethylaminopropylamino]-6-methyl-5H-pyrido[3',4':4,5] pyrrolo[2,3-g]isoquinoline (BD-40) (NSC-327471D) is an aza-ellipticine derivative with a promising antitumor activity (M. Marty, C. Jasmin, P. Pouillard, C. Gisselbrecht, G. Gouvenia, and H. Magdalainat, 17th Annual Meeting of the American Society of Clinical Oncology, C-108, 1981) and less toxicity than ellipticine. We have compared the effects of ellipticine, ...
Kleuser B - - 1985
The effect of submicromolar concentrations of the K+ ionophore valinomycin on proliferation, viability, distribution of cell population over phases of the cell cycle, and cellular adenosine triphosphate content of different permanent rodent cell lines in vitro was investigated. Valinomycin inhibits proliferation of all cell lines tested with a saturating effect ...
Reiter T - - 1985
We examine changes in protein synthesis that accompany suspension (i.e. shape alteration) of anchorage-dependent and anchorage-independent cells using a newly developed cell fractionation procedure based on detergent extraction. Using this procedure, a cell can be divided into four distinct and independent fractions: soluble, cytoskeleton, chromatin and nuclear matrix-intermediate filament. This ...
Chen J W - - 1985
Lysosome-associated membrane protein (LAMP)-1, a major glycoprotein of mouse embryo 3T3 cells and specifically associated with the lysosomal membrane, has been identified in P388 macrophage cells and compared with the homologous glycoprotein of NIH 3T3 cells. Immunofluorescence microscopy with anit-LAMP-1 monoclonal antibodies shows that the antigen was distributed throughout P388 ...
Knudson C B - - 1985
Hyaluronate levels change dramatically during morphogenesis of various tissues and organs. Morphological detection of the exact temporal and spatial distribution patterns of hyaluronate may help to elucidate its role in morphogenesis. Since no specific direct method for visualizing hyaluronate with the light or electron microscope is currently available, we have ...
Scher B M - - 1985
The addition of certain proteases to cultures of Friend virus-infected mouse erythroleukemia cells can induce up to 90% of the cells in culture to become hemoglobin-containing, as assessed by positive staining for benzidine (B+). Because the mechanism of this protease action is unknown, media components were studied as possible targets ...
Chan L N - - 1985
The effects of the plant toxin abrin on normal mouse embryonic fibroblasts (MEF), an untransformed mouse cell line (NIH 3T3), and two mouse tumor cell lines (LMTK- and S-180) were studied. Measurements of cell growth and colony formation showed that MEF and S-180 cells were more sensitive to abrin intoxication ...
Gal S - - 1985
The major excreted protein (MEP) of transformed mouse fibroblasts is a mannose 6-phosphate-containing glycoprotein whose synthesis and secretion are increased in malignantly transformed 3T3 cells and whose synthesis is increased by treatment of 3T3 cells with tumor promoters or growth factors. When pulse-labeled extracts from Kirsten virus-transformed NIH 3T3 (KNIH) ...
Salimans M M - - 1985
Growth of mouse neuroblastoma cells becomes stationary when cultured in serum-free medium. Within 60 h, the protein-synthesizing capacity of the cells declines to 25% as compared to that of exponentially growing cells. The transitional activity of the crude ribosomal salt washes from serum-deprived and control cells was compared in in ...
Brooks R F - - 1985
By separating large and small 3T3 cells we show here that cell growth (in volume) after stimulation from quiescence is not 'autocatalytic'. Rather, large cells grow significantly more slowly, in relative terms, than small cells. It follows that 3T3 cells do not require a size control mechanism operating at the ...
Fransson L A - - 1985
35S-Labelled heparan sulfates derived from the culture medium (extracellular), a trypsinate of the cells (pericellular) and the cell residue (intracellular) of quiescent normal, proliferating normal or SV40-transformed 3T3 cells were analyzed for charge heterogeneity, by ion exchange chromatography and for self-affinity, by chromatography on heparan sulfate-agarose gels. Quiescent normal cells ...
Sivak A - - 1985
Although the evidence is not definitive, available information suggests that hepatocytes from appropriate rodent, and possibly other mammalian species, can be used to obtain metabolic activation in transformation assays that utilize cells with limited endogenous metabolic capabilities. On the basis of the available information, it appears that rat hepatocytes may ...
O'Neill C - - 1985
The effects of some chemically defined growth factors on the locomotion of quiescent Swiss 3T3 fibroblasts have been studied. A computer digitiser has been used to facilitate recording the paths followed by cells in time-lapse films; this method allows 500 cell-hours to be recorded in 1 h of real time. ...
Wang P Y - - 1984
In a previous study of the dextran gel sphere model system, a possible correlation between cell deformability and agglutinability by concanavalin A was indicated. Cell deformability was evaluated as filtrability, using polycarbonate membrane filtration. With 25-mm diameter filters and 5-ml cell suspensions at (0.8-16) X 10(5) cells/ml, the filtrability at ...
Stenn K S - - 1984
In contrast to freshly isolated cells, some cultured keratinocytes have the ability to adhere and spread in protein-free media. Reported here are experiments testing the hypothesis that the social history of keratinocytes influences their ability to spread in defined media. The experiments indicate that confluent cells lack the ability to ...
Tamura T - - 1984
The endogenous cellular oncogene products, pp60c-src, exhibits a protein kinase activity, but is itself a phosphoprotein. Based on the assumption that pp60c-src might play a role in the control of cell proliferation, we have studied its behaviour as a substrate for phosphorylation known to occur when quiescent, serum-deprived cells are ...
Rønning O W - - 1984
When exponentially growing NHIK 3025 cells were shifted from medium containing 30% serum to medium containing 0.03% serum the rate of net protein accumulation was reduced due to both a reduction in the rate of protein synthesis and an increase in the rate of protein degradation. This change in growth ...
Morgan R A - - 1984
We report here comparative studies of DNA methylation and expression of intracisternal A-particle (IAP) genes in murine plasmacytomas, TEPC-15 and MOPC-315, in NIH/3T3 embryo fibroblasts, and in normal liver from young adult BALB/c mice. In Southern blot analysis using methylation-sensitive restriction enzymes, we observed hypomethylation of 4.7- and 5.3-kilobase pair ...
Fan D - - 1984
SV40-transformed 3T3 cells formed microtubular crystals in the cytoplasm when treated with vinblastine sulfate. Annulated lamellae, an unusual intracellular organelle found in some actively proliferating cell types, appeared concurrently with the formation of microtubular crystals. Although crystals were also seen in non-transformed 3T3 cells treated with vinblastine, annulated lamellae were ...
Chessebeuf M - - 1984
The enhancement of L-tyrosine aminotransferase activity by dexamethasone, an exclusive function of the liver, was serially measured at different passages of eight rat liver epithelial cell lines initiated and continuously grown in either a serum-supplemented medium or a serum-free medium. The enzyme basal activity was found to be 5.4 +/- ...
Sato S - - 1984
Clonal B16 mouse melanoma conv cells are tumorigenic spindle-shaped cells (S-type cells) exhibiting tyrosinase activity and melanosomes under usual culture conditions. When the cells passaged on glass substratum were plated for colony formation on plastic substratum in Eagle's minimum essential medium (MEM) with 10% calf bovine serum, most of them ...
Gronostajski R M - - 1984
When cultured fibroblasts are deprived of serum, the degradation of long-lived proteins and RNA increases, the cells stop proliferating, and they decrease in size. To determine the role of the increased protein catabolism in these responses, we studied the effects of inhibitors of intralysosomal proteolysis in Balb/c 3T3 cells. When ...
Smith J B - - 1984
La3+ stimulated quiescent Swiss 3T3 and 3T6 cells to enter the DNA-synthesizing S phase of the cell cycle. La3+ and insulin interacted synergistically to increase DNA synthesis. A brief exposure of the cells to soluble LaCl3 optimally stimulated entry into S. La3+ was similar to A13+ in its mitogenic properties ...
Seuwen K - - 1984
The method for differential fluorescence staining of cellular RNA and DNA by acridine orange (AO) was optimized for 3T3 and SV40-3T3 cells. Cellular contents of DNA and of ribosomal RNA (rRNA) were determined by dual-channel flow cytometry during cell-density-dependent proliferation and after stimulation of quiescent cells. With increasing density of ...
Grimaldi P - - 1984
Cell lines were derived from ob17 preadipocyte cells by focus formation after transfer of the complete early region of polyoma virus (ob17PY) or of a modified genome encoding only the middle T protein (ob17MT). Both ob17PY and ob17MT cell lines exhibited a high cloning efficiency in agarose medium containing 10% ...
Goldberg R L - - 1984
3T3 cells have a large, pericellular coat which contains 30 times more hyaluronate than the amount of cell surface hyaluronate associated with simian virus 40-transformed 3T3 (SV-3T3) cells. On the other hand, SV-3T3 cells have high affinity binding sites for exogenously added hyaluronate, whereas 3T3 cells have much lower affinity ...
Durkin J P - - 1984
NRK cells infected with a temperature-sensitive, transformation-defective mutant of avian sarcoma virus (ASV), tsLA23, are transformed at 36 degrees C, but at 40 degrees C they behave as nontransformed cells because of the inactivation of the abnormally thermolabile pp60v-src product of the virus' transforming src gene. At 40 degrees C, ...
Schroder E W - - 1984
Retinoic acid (RA; beta-all-trans) inhibits the proliferation of both murine 3T3 cells and human HeLa cells. Flow cytometric analyses of exponentially growing cultures show that 3T3 cells are inhibited during the S phase of their cell cycle, while HeLa cells show only a small increase in G1 phase cells. RA ...
Mori Y - - 1984
Microtubule poisons such as colchicine, colcemid and vinblastine caused extrusion of nuclei of murine suspension culture cells (mastocytoma p-815 cells, myeloma PU-3 cells, leukemia M1 cells). Enucleation did not follow spontaneously in most cells, but it did occur when the treated cells were centrifuged in Separate-L gradient. These poisons did ...
Cockle S M - - 1984
Degradation of endogenous proteins in five normal and five I-cell (mucolipidosis II) storage disease human fibroblasts was compared. In growing cultures (low density) long half-life proteins were degraded normally in each group of cells. However, the enhancement of proteolysis when confluence is reached, which we have characterised previously as being ...
Zuckerman S H - - 1984
Comparative two-dimensional gel electrophoretic studies were performed on mitochondrial proteins in nontransformed mouse 3T3 cells and in SV40-transformed 3T3 cells, SV-T2. Two polypeptides, of 58 and 40 kDa, were present in increased amounts in SV40-transformed cells. These polypeptides were demonstrated to be nuclear-coded mitochondrial proteins by their absence in mitochondrial ...
Harel L - - 1984
We recently fractionated, from the culture medium of 3T3 cells, a thermolabile inhibitory diffusible factor (IDFN) with a molecular weight of about 40,000 daltons, which decreased nucleic acids synthesis of stimulated target 3T3 cells. In the present publication the inhibitory activities of IDFN (produced by 3T3 cells) and IDFT (produced ...
Gronostajski R M - - 1984
To study the relation of overall rates of protein degradation in the control of cell growth, we determined if transformation of fibroblasts to tumorigenicity affected their rates of degradation of short- and long-lived proteins. Rates of protein degradation were measured in nontumorigenic mouse Balb/c 3T3 fibroblasts, and in tumorigenic 3T3 ...
Kimura H - - 1984
The sensitivity to bleomycin of JTC-11 cells derived from Ehrlich ascites tumor was modified by both serum concentration and superinoculation on a sheet of Swiss 3T3 cells. The dose-survival curve of the JTC-11 cells was biphasic or triphasic, with a sensitive phase at lower doses (less than 10 micrograms/ml) and ...
Killion J J - - 1984
The transmembrane potential difference, Em, and DC membrane resistance were measured in 3T3 and polyoma virus-transformed 3T3 cells. Em was a function of cell density and was -12 and -25 mV for the normal and transformed cells, respectively. The external concentrations of K+, Na+, and Cl were varied in order ...
Flatow U - - 1984
Since butyrate inhibits DNA synthesis and cell growth, we adapted NIH 3T3 cells to grow in butyrate to study its effects on retroviral cell transformation. In cultures of butyrate-adapted NIH 3T3 cells infected with Harvey Sarcoma Virus, no foci were formed; however, there was evidence of retroviral replication, and the ...
Facci L - - 1984
Ganglioside GM1 promoted neuritogenesis of neuroblastoma cells, neuro-2a clone, in monolayer culture. GM1 bound to neuro-2a cells in three distinct forms, one removable by treatment with serum-containing solutions, one serum-resistant and labile to trypsin treatment, and one resistant to serum and trypsin treatments. The proportions among the three forms of ...
Itkes A V - - 1984
Sequential treatment of NIH 3T3 cells with theophylline and actinomycin D results in an enhancement of 2',5'-oligo(A) synthetase activity 2-3-fold exceeding that induced by treatment with theophylline only. This 'superinduction' phenomenon suggests the existence of a negative control of the enzyme that involves a labile, transcription-dependent factor.
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