Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| confirmation of the assignment of the locus determining ada to chromosome 20 in man: data on possible synteny of ada and itp in human-chinese hamster somatic cell hybrids. | 1976 | 185012 | |
| chromosomal assignment of the gene for human red cell adenylate kinase (ak1) in man-chinese hamster somatic cell hybrids. | 1976 | 185020 | |
| simian virus 40 mutants carrying two temperature-sensitive mutations. | five temperature-sensitive mutants of simian virus 40 containing two temperature-sensitive mutations were isolated. the double mutant of the a and d complementation groups, like the d mutants, failed to complement by conventional complementation analysis and did not induce host dna synthesis at 40 degrees c. however, under conditions that suppressed the d defect, the a:d double mutant expressed only the a defect. thus, viral dna replication dropped rapidly after this mutant was shifted from perm ... | 1976 | 185417 |
| [transmission and expression of malignancy in somatic hybrid cell lines (hamster/hamster, mouse/mouse, hamster/mouse)]. | various characteristics of transformation were studied in subclones isolated from a hybrid cell line obtained by fusion of two chinese hamster sub-lines having the same origin but presenting different properties, particularly in respect to heterotransplantability. different subclones were obtained by cloning on semisoft agar. transplantability, plating efficiency, agglutinability by concanavalin a and actinomycin d resistance were studied in parallel with the evolution of the karyotype to try to ... | 1976 | 186142 |
| transformation of chinese hamster embryo cells with an avian sarcoma virus ts mutant. | chinese hamster embryo cells were transformed with temperature-sensitive mutant of the schmidt-ruppin strain of rous sarcoma virus-subgroup a (ts ny68s ra-a). the developed cell line elicited the morphological transformation at a permissive temperature of 35 degrees c, whereas after a shift to a non-permissive temperature of 40 degrees c the cells reverted to a normal phenotype. tests for the presence of avian sarcoma group-specific antigen showed that the antigen was not expressed both at permi ... | 1976 | 186335 |
| [role of oncogenic viruses in the formation of dna provirus during acute infection of chinese hamster cells by tick-borne encephalitis viruses]. | 1976 | 187396 | |
| a correlation between membrane glycopeptide composition and losses in concanavalin a agglutinability induced by db-camp in chinese hamster ovary cells. | 1976 | 187438 | |
| decreased cyclic amp and insulin responses to glucose in pancreatic islets of diabetic chinese hamsters. | the dose as well as the time kinetics of insulin and adenosine-3',5'-monophosphate (cyclic amp) responses to glucose were compared in pancreatic islets isolated from normal and diabetic chinese hamsters. the insulin content in diabetic islets was about one-half that in normal islets. insulin release in diabetic islets incubated for 10 min with glucose 60-1000 mg/100 ml was from one-third to one-half that in normal islets. glucose 1000 mg/100 ml stimulated three-fold increases in insulin release ... | 1976 | 187518 |
| evolutionary trends in 18s ribosomal rna nucleotide sequences of rat, mouse, hamster and man. | the large t1 ribonuclease fragments of 18s ribosomal rna from four mammalian species, rat, mouse, hamster and man, were compared by two-dimensional homochromatography fingerprinting. the nucleotide sequences of the large t1 ribonuclease fragments, polypyrimidines and polypurines which were different among the four mammalian species were determined and compared. the method used for determining nucleotide sequences utilizes 32p-labeling of oligonucleotides at their 5'-termini by polynucleotide kin ... | 1976 | 188015 |
| effects of temperature and antibody on the cyclid growth of vesicular stomatitis virus. | to see the effects of temperature on the interrelated cyclic production of standard and defective interfering (di) particles of vesicular stomatitis virus, a temperature-sensitive (ts) g114 mutant was passaged successively at different temperatures and the production of the two types of viral particles as well as the ability of chinese hamster ovary cells to survive each passage was continuously monitored. when the temperature was nonpermissive for standard virus, the synthesis of both standard ... | 1977 | 189064 |
| assembly of viral membranes. i. association of vesicular stomatitis virus membrane proteins and membranes in a cell-free system. | we report here an in vitro system designed to study the interactions of vesicular stomatitis virus (vsv) proteins with cellular membranes. we have synthesized the vsv nucleocapsid (n) protein, nonstructural (ns) protein, glycoprotein (g protein), and membrane (m) protein in a wheat germ, cell-free, protein-synthesizing system directed by vsv 12 to 18s rna. when incubated at low salt concentrations with purified cytoplasmic membranes derived from chinese hamster ovary cells, the vsv m andg protei ... | 1977 | 189082 |
| assignment of the integration site for simian virus 40 to chromosome 17 in gm54va, a human cell line transformed by simian virus 40. | gm54va human cells transformed by simian virus 40 (sv40) were fused with peritoneal macrophages obtained from three different mouse strains. all 27 hybrid clones studied were positive for sv40 tumor antigen in 100% of their cells and contained human chromosome 17. human chromosome 17 was the only human chromosome present in five of the hybrid clones. fusion of gm54va cells and either thymidine kinase (ec 2.7.1.75)-deficient mouse or chinese hamster fibroblasts resulted in the growth in hypoxanth ... | 1977 | 189310 |
| variation in enterotoxigenicity of escherichia coli. | the possibility that the variable severity of diarrheal disease due to enterotoxigenic escherichia coli might be explained by quantitative differences in the activity of heat-labile enterotoxin was examined. the amount of toxin secreted by 13 enteropathogenic strains of e. coli was quantitated by measurements of the toxin-dependent increase in adenosine 3':5'-cyclic phosphate (cyclic amp) in chinese hamster ovary cells. the activity ranged from 150 pmol of cyclic amp/ml per mg of protein to 4,04 ... | 1977 | 190329 |
| action of cyclic nucleotide analogues in chinese hamster ovary cells. | cyclic nucleotide analogues have been tested for their ability to cause the morphological conversion of chinese hamster ovary cells in culture, as well as for effects on cyclic amp-related enzymes. the ability of the analogues to inhibit the cyclic amp phosphodiesterase activity and to activate the cyclic amp-dependent protein kinase activity in cell extracts has been measured. cell cultures were incubated with the analogues and the effects on morphology, intracellular level of cyclic amp, and i ... | 1977 | 191090 |
| chromosomal assignment of the gene for human red cell adenylate kinase (ak1) in man-chinese hamster somatic cell hybrids. | 1976 | 192371 | |
| growth and biochemical characteristics of a detachment variant of cho cells. | a variant subline of chinese hamster cells (line cho) was isolated that had increased resistance to detachment from the substratum. comparisons between parental and variant cells of the complex carbohydrates liberated during trypsin detachment showed that the variant cells synthesized little or no hyaluronic acid. these cells also had reduced amounts of other complex carbohydrates in the cell periphery. however, parental and variant cells did not differ in morphology, growth control, or cyclic a ... | 1977 | 192736 |
| heterogeneity of karyotype and growth potential in simian virus 40-transformed chinese hamster cell clones. | five clones of chinese hamster cells transformed with simian virus 40 (sv40) were isolated from methylcellulose and characterized as to giemsa-banded karyotype, dna content, saturation density, agglutination with concanavalin a, and tumorigenicity. chromosome analysis and dna content studies at early passage revealed that the genetic complement for all clones was predominantly near tetraploid. all cultures examined contained a proportion of hypertetraploid cells. nonrandom chromosome changes inc ... | 1977 | 192902 |
| regulation of hypoxanthine transport by cyclic nucleotides in cultured chinese hamster lung fibroblasts. | 1977 | 193444 | |
| mechanism of action of inosine dialdehyde (nsc 118994) in the inhibition of proliferation of tumor cells in culture. | inosine dialdehyde (inox), the periodate oxidation product of inosine, inhibited the proliferation of various tumor cell lines in suspension culture in a concentration-dependent manner. a concentration of about 1 mm was required to completely inhibit the proliferation of novikoff rat hepatoma and mouse l-cells, whereas about 0.1 mm completely inhibited the proliferation of l1210 and p388 mouse leukemia and chinese hamster ovary cells. inox inhibited in a similar time- and concentration-dependent ... | 1977 | 193637 |
| spontaneous, chemical and viral mutagenesis in temperature-sensitive glutamine-requiring chinese hamster cells. | 1977 | 194150 | |
| the dose-response relationship for ethyl methanesulfonate-induced mutations at the hypoxanthine-guanine phosphoribosyl transferase locus in chinese hamster ovary cells. | the frequency of ethyl methanesulfonate (ems)-induced mutations to 6-thioguanine resistance in a chinese hamster ovary cells clone k1-bh4 was studied at many ems doses including the minimally lethal range (0-100 microng/ml) as well as the exponential killing portion (100-800 microng/ml) of the survival curve. the mutation frequency increases approximately in proportion with increasing ems concentration at a fixed treatment time. the pooled data for the observed mutation frequency, f(x), as a fun ... | 1975 | 194347 |
| modulation of drug permeability in chinese hamster ovary cells. possible role for phosphorylation of surface glycoproteins. | we have previously reported that the uptake of colchicine and other drugs in chinese hamster ovary (cho) cells can be greatly enhanced by the addition of metabolic inhibitors such as cyanide (see, y.p., carlsen, s.a., till, j.e. and ling, v. (1974) biochim. biophys. acta 373, 242-252). this has led us to postulate the presence of an active drug permeability barrier in these cells. in this paper we provide evidence for the dependence of this permeability barrier on intracellular atp levels. colch ... | 1992 | 195605 |
| changes in radiosensitivity induced by cyclic nucleotides and chemical radioprotection. | cyclic amp has a radioprotective effect and its aministration results in a significant increase in ld50/30 values in chinese hamsters. the efficiency of these radioprotective effects is comparable to that of such radioprotective compounds as aet and cystamine + mexamine. cyclic gmp is responsible for significant radiosensitizing effects. changes in radiosensitivity after administration of cyclic nucleotides are both immediate and delayed and correlate closely with dose and time of administration ... | 1992 | 195849 |
| purineless death: ribosomal rna turnover in a purine-starved ade- mutant of chinese hamster cells. | when v79 pur 1, a purine-requiring auxotroph of a chinese hamster cell line, is deprived of adenine, nucleic acid and protein synthesis decline rapidly. however, on continuous starvation rna and dna synthesis recommences to reach approximately 30% of the normal level between 12 to 24 h starvation. this is accompanied by a rise in the intracellular nucleotide pool. utilizing mengovirus, which gives a productive infection in v79 pur 1 cells even under conditions of starvation, we can show that rrn ... | 1977 | 195948 |
| simian virus 40-chinese hamster kidney cell interaction. iii. characteristics of chemical induction in a clone of virogenic transformed cells. | a number of chemical and physical agents were screened to determine their effectiveness in inducing simian virus (sv40) production in a virogenic clone of sv40-transformed chinese hamster cells. mitomycin c (mc) was the most effective inducing agent, and mc induction was further characterized. it was found that levels of infectious sv40 dna were increased above control levels as early as 6 h after addition of mc to the culture medium and reached maximum levels by 48 h. virus capsid (v) antigen a ... | 1977 | 196036 |
| simian virus 40-chinese hamster kidney cell interaction. iv. enhanced virus replication in infected cells upon treatment with mitomycin c. | chinese hamster kidney cells are semi-permissive to simian virus 40 (sv40). exposure to mitomycin c (mc) of chinese hamster kidney cells infected with sv40 dna enhanced the yield of infectious virus 10- to 100-fold. this stimulation occurred whether the treatment was performed before or after infection. a simultaneous increase in the number of v antigen-synthesizing cells and virus-producing cells, as well as the virus burst size, was observed upon mc pretreatment, whereas the proportion of t an ... | 1977 | 196038 |
| chinese hamster cell mutant with defective mitochondrial protein synthesis. | 1977 | 196202 | |
| correlation between changes in intracellular level of cyclic amp, activation of cyclic amp-dependent protein kinase, and the morphology of chinese hamster ovary cells in culture. | 1977 | 196552 | |
| cytochemical study of glucose-6-phosphatase in chinese hamster testis. | 1977 | 196695 | |
| initiation points for dna replication in nontransformed and simian virus 40-transformed chinese hamster lung cells. | randomly growing chinese hamster lung cells were pulse-labeled with 3h-thymidine, and the replicating forks of individual dna fibers were visualized by autoradiography. when grown in complete medium, wild-type sv40-transformed cells had more forks per unit length of dna than nontransformed cells. in isoleucine-depleted medium, wild-type sv40-transformed cells had fewer forks per unit length than those few nontransformed cells (1-3% of the population) which continued dna replication. cells transf ... | 1977 | 196764 |
| synteny of the genes for thymidine kinase and galactokinase in the mouse and their assignment to mouse chromosome 11. | we have studied the expression of mouse galactokinase in human-mouse somatic cell hybrids segregating mouse chromosomes. since concordant segregation of the expression of mouse galactokinase and the presence of mouse chromosome 11 were observed in the hybrid clones, we conclude that the gene for mouse galactokinase is located on mouse chromosome 11. we have also investigated the expression of mouse galactokinase in somatic cell hybrids between thymidine kinase-deficient chinese hamster cells and ... | 1977 | 196814 |
| effect of staphylococcus aureus delta toxin on chinese hamster ovary cell morphology and y-1 adrenal cell morphology and steroidogenesis. | since staphylococcus aureus delta toxin previously had been shown to increase the cyclic adenosine 3',5'-monophosphate (camp) content of guinea pig ileum, the effect of delta toxin on such camp-mediated responses as morphogenesis and steroidogenesis in cultured tissue cells was examined. in contrast to cholera toxin, delta toxin did not cause spindling of chinese hamster ovary cells. unlike adrenocorticotropin or cholera toxin, delta toxin was unable to cause rounding of y-1 adrenal cells or to ... | 1977 | 197006 |
| control of cell shape by adenosine 3' : 5' - phosphate in chinese hamster ovary cells: studies of cyclic nucleotide analogue action, protein kinase activation, and microtubule organization. | 1977 | 197834 | |
| gene mapping in mus musculus by interspecific cell hybridization: assignment of the genes for tripeptidase-1 to chromosome 10, dipeptidase-2 to chromosome 18, acid phosphatase-1 to chromosome 12, and adenylate kinase-1 to chromosome 2. | chinese hamster x mouse somatic cell hybrids segregating mouse chromosomes were examined for their mouse chromosome content using trypsin-giemsa (gtg) banding and hoechst 33258 staining techniques. simultaneously, they were scored for the presence of 24 mouse enzymes. the results confirm the assignments of 11 genes previously mapped by sexual genetics: dip-1 and id-1 to chromosome 1; pgm-2 and pgd to 4; pgm-1 to 5; gpi-1 to 7; gr-1 to 8; mpi-1 and mod-1 to 9; np-1 and es-10 to 14. they also conf ... | 1977 | 198184 |
| cyclic amp-protein-dna complex formation in mammalian cell-free systems. | a cytoplasmic protein fraction from kb and chinese hamster ovary cells (cho-kl) was shown to bind in vitro to camp and subsequently to dna-cellulose. this protein complex was not found in de-52 purified cho-k1 camp-dependent protein kinases. the complex appeared to exist as a small fraction of the total camp binding proteins, preferred native to denatured dna and exhibited multiple sedimentation coefficients in glycerol gradients. this complex, after elution from the dna cellulose column, was sh ... | 1977 | 198443 |
| control effects of cyclic nucleotides on the proliferation activity of the bone marrow cells of the chinese hamster in vivo and their relation to the radiosensitivity. | 1976 | 199053 | |
| the control of cell proliferation by preformed purines: a genetic study. i. isolation and preliminary characterization of chinese hamster lines with single or multiple defects in purine "salvage" pathways. | sublines with single or multiple defects in purine "salvage" enzymes were isolated from the chinese hamster fibroblastic line gma32 through single or successive one-step selections for resistance to purine analogs. they were examined for their ability to incorporate purine bases and nucleosides into macromolecules, for their sensitivity to growth inhibitory purines, and for their rescue by exogenous purines from deprivation imposed by metabolic inhibitors of endogenous synthesis. the results sho ... | 1977 | 199954 |
| studies on adenosine 3',5'-phosphate-binding and adenosine 3',5-phosphate-dependent protein kinase activities associated with subcellular fractions of chinese hamster ovary cells. | both cyclic amp-binding and cyclic amp-dependent protein kinase activities exist in chinese hamster ovary cell extract. competition experiments demonstrate that the binding is specific for cyclic amp. all cellular elements including nucleus, mitochondria, plasma membrane, microsome, ribosome and cytosol contain both activities. binding activity is highest in the cytosol and lowest in the nucleus. each fraction contains endogenous protein kinase activity which is insensitive to cyclic amp activat ... | 1977 | 200277 |
| chromosomal alterations in a chinese hamster cell line transformed in vitro by sv40 virus. | 1977 | 200554 | |
| a comparison of camp phosphodiesterases in normal, malignant, and somatic cell hybrids. | hybrids (pcm) between a malignant mouse lymphoma suspension cell line (p388f-36) and a normal chinese hamster fibroblastic cell line (ch23) have already been isolated in this laboratory. investigations were carried out on the camp phospodiesterases of the parents and two of these hybrids--pcm2 and pcm3. pcm3 shows a rather unusual growth characteristic in that a considerable proportion of the cells exist at any one time either in suspension or only loosely attached to the substratum, the remaini ... | 1977 | 201244 |
| an investigation of the homology of guanylate kinase isozymes in mammals and further evidence for multiple guk gene loci. | guanylate kinase in the red cells of 63 different mammalian species was studied by electrophoresis and multiple molecular forms of the enzyme were found in all species. two species were investigated in more detail. using molecular weight estimates as a criterion of homology, the fallow deer and the chinese hamster were found to have isozymes that corresponded to isozyme e, f, and g of man. variation in the guanylate kinase isozymes was detected in a small population of orangutans. results sugges ... | 1977 | 201245 |
| the role of butyrate in the reverse transformation reaction in mammalian cells. | the reverse transformation reaction of chinese hamster ovary cells from compact, epithelial-like, randomly growing, heavily knobbed, lectin reactive cells into stretched, tighly adherent, smooth-surfaced, lectin resistant, fibroblast-like cells normally elicited by dibutyryl camp can be produced to its complete extent by n6-monobutyryl camp or 8-bromo-camp, o2'-monobutyryl camp is ineffective as is camp itself in the absence of an inhibitor of phosphodiesterase activity. in the presence of a pho ... | 1978 | 201654 |
| further evidence for the genetic origin of mutations in mammalian somatic cells: the effects of ploidy level and selection stringency on dose-dependent chemical mutagenesis to purine analogue resistance in chinese hamster ovary cells. | 1994 | 201836 | |
| virus production with a newly developed microcarrier system. | primary cell cultures as well as established lines have been grown on a recently developed microcarrier configuration that overcomes the problem of toxicity attendant on earlier developments in this technology. virus yields from these cells propagated on the new microcarriers have been measured. microcarrier-grown cells, when compared to roller-bottle-grown cells, gave virus yields on a per-cell basis that varied from slightly greater with the sindbis virus-chinese hamster ovary cells and polio- ... | 1977 | 202193 |
| cyclic amp levels and types i and ii cyclic amp-dependent protein kinase activity in synchronized cells and in quiescent cultures stimulated to proliferate. | cyclic amp as well as the specific activity of cyclic amp-dependent protein kinase decreased from the first two hours after chinese hamster ovary cells in plateau phase were stimulated to proliferate by tripsinization of confluent cultures and dilution in fresh media. from two to five hours after this stimulation, the cyclic amp level and the specific activity of cyclic amp-dependent protein kinase increased two-fold. there was a 40--50% increase in the degree of activation of cyclic amp-depende ... | 1978 | 202331 |
| sex- and line-dependent differences of renal alpha-galactosidase and beta-galactosidase activities in two highly inbred lines of chinese hamsters with spontaneous diabets. | 1978 | 202977 | |
| regulation of de novo purine biosynthesis in normal and 8-azaguanine-resistant chinese hamster cells. | azaguanine-resistant mutants of chinese hamster ovary cells were isolated following mutagenesis with icr-17og. of the eight mutant isolates examined, only one, ag-5 had detectable hypoxanthine(guanine)phosphoribosyltransferase activity. under normal conditions of growth, de novo purine biosynthesis in the mutants was not significantly different from wild type. however, when the cultures were starved for glutamine over a 2 h period before measuring 5'phosphoribosyl formylglycinamide (a relative m ... | 2003 | 203317 |
| assignment of the genes for thymidine kinase and galactokinase to mus musculus chromosome 11 and the preferential segregation of this chromosome in chinese hamster/mouse somatic cell hybrids. | 1977 | 204065 | |
| transfer of the human genes coding for thymidine kinase and galactokinase to chinese hamster cells and human-chinese hamster cell hybrids. | cotransfer of two linked human genes, coding for the enzymes thymidine kinase (tk) and galactokinase (gak) was demonstrated following incubation of chinese hamster tk-deficient cells with isolated human chromosomes. the 5 colonies which were isolated all expressed a stable tk-positive phenotype. cotransfer of the human genes coding for tk and gak has also been observed in experiments in which isolated human chromosomes were incubated with tk-deficient human-chinese hamster cell hybrids. these re ... | 1977 | 204067 |
| expression of "early" and "late" viral functions in a somatic cell hybrid between a mouse cell and a spontaneous yielder sv 40-transformed chinese hamster cell. | a somatic cell hybrid (cl. 6d) was originated from the fusion of mouse 3t3-4e) and spontaneous yielder sv 40-transformed chinese hamster (chk/svlp ag) cells. during the early stages of its history, the c1. 6d hybrid underwent a rapid chromosome loss, preferentially loosing hamster chromosomes. this was not a constant tendency of the hybrid cells. as the parental chk)svlp ag cells, the hybrid cells were always found 100 per cent sv40 t-antigen positive. while chk/svlp ag cells infectious sv 40 dn ... | 1978 | 204268 |
| cyclic nucleotide metabolism in hela and chinese hamster cells after treatment with chlorambucil. | 1993 | 204313 | |
| collagen biosynthesis by cultured chinese hamster lung cells. cell-free synthesis of procollagen alpha chains. | cell-free extracts from the htl clone of cultured chinese hamster lung cells efficiently promote the incorporation of proline into newly synthesized material, 50% of which is digestible to small peptides by highly purified bacterial collagenase. the synthesis of the these products occurs under optimal protein synthesis conditions and is inhibited by puromycin. sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the cell-free synthesized material reveals a major collagenase sensitive pea ... | 1978 | 204330 |
| direct fluorescent assay of urokinase and plasminogen activators of normal and malignant cells: kinetics and inhibitor profiles. | a direct rate assay for plasminogen activator has been developed using a synthetic fluorogenic peptide substrate, 7-(n-cbz-glycylglycylargininamido)-4-methylcoumarin trifluoroacetate. the assay correlates well with the standard 125i-labeled fibrin plate assay using highly purified urokinase, culture fluids from wi-38, chinese hamster vary or hela cells, or rous sarcoma virus-transformed chick fibroblasts as the source of plasminogen activator. the assay is sensitive, rapid, and linear throughout ... | 1978 | 204931 |
| cotransfer of thymidine kinase and galactokinase genes by chromosome-mediated gene transfer. | the chinese hamster genes for thymidine kinase (atp:thymidine 5'-phosphotransferase, ec 2.7.1.75) and galactokinase (atp:d-galactose 1-phosphotransferase, ec 2.7.1.6) have been cotransferred to mouse cells by chromosome-mediated gene transfer. hamster metaphase chromosomes were incubated with mouse b82 cells and 22 independent colonies were isolated in a selective medium. all of the 12 colonies analyzed expressed the donor form of thymidine kinase; the hamster form of galactokinase was also expr ... | 1978 | 204939 |
| post-treatment with caffeine and the induction of gene mutations by ultraviolet irradiation and ethyl methanesulphonate in v-79 chinese hamster cells in culture. | the effect of caffeine on v-79 chinese hamster cells after ultraviolet irradiation or treated with ethyl methanesulphonate was investigated. caffeine strongly potentiated the killing of both agents, but it had no effect on the induction of mutations at the hypoxanthine-guanine phosphoribosyl transferase locus. the results are consistent with the notion that caffeine slows down an error-prone post-replicative repair mechanism without changing the mutation frequency. | 1992 | 205782 |
| assignment of the gene for adenosine kinase to chromosome 14 in mus musculus by somatic cell hybridization. | evidence is presented for the assignment of the gene for adenosine kinase to mus musculus chromosome 14 by synteny testing and karyotypic analysis of mouse x chinese hamster somatic cell hybrid clones. adok and two enzymes previously mapped to mouse chromosome 14, np and es-10, were expressed concordantly in 29 hybrid clones. chromosome analysis confirmed this assignment. syntenic evidence is also presented using several clones of a gene transfer system in which the gene for human hprt had integ ... | 1978 | 206412 |
| histone phosphorylation and chromatin structure during mitosis in chinese hamster cells. | 1978 | 206429 | |
| a host range difference between herpes simplex virus types 1 and 2. | the infectivities of several strains of herpes simplex virus type 1 and type 2 were measured by plating on established human and chinese hamster cell lines. whereas all the type 1 strains reproducibly showed a 10(4)-fold lower titre on the chinese hamster cells, the type 2 strains showed only a 10- to 100-fold lower titre. this host range difference has been used in the analysis of recombinants between type 1 and type 2 viruses. | 1978 | 206659 |
| specific changes in the oligosaccharide moieties of vsv grown in different lectin-resistnat cho cells. | the carbohydrate moieties of the g glycoprotein of vesicular stomatitis virus (vsv) grown in three distinct lectin-resistant (lecr) chinese hamster ovary (cho) cell lines have been compared by fine structural analysis of radiolabeled glycopeptides. the mutant wgariii, selected for resistance to wheat germ agglutinin (wga), produces vsv containing g glycoprotein specifically lacking in sialic acid. the mutant phari, selected for resistance to phytohemagglutinin (pha) and previously shown to lack ... | 1978 | 207434 |
| the association between mutagenicity and adduct formation of 1,2,7,8-diepoxyoctane and 1,2,5,6-diepoxycyclooctane. | the mutagenicity of 1,2,5,6-diepoxycyclooctane (deco) and 1,2,7,8-diepoxyoctane (deo) was investigated using diploid chinese hamster lung cells. 6-thioguanine (6-tg) resistance was used as the marker for mutagenicity testing: deo was found to be genetically active; deco, on the contrary, totally inactive. deo readily formed adducts with radiolabeled nucleotides, while deco failed to do so, as demonstrated through thin-layer chromatography (tlc) and the shift of the ultraviolet absorption maximum ... | 1992 | 207451 |
| a study of cultured fetal and sv40-transformed chinese hamster kupffer cells. | 1992 | 207542 | |
| comparative mutagenicity of alkylsulfate and alkanesulfonate derivatives in chinese hamster ovary cells. | mutation induction and cell killing produced by selected alkylsulfates and alkanesulfonates have been quantitated using the chinese hamster ovary/hypoxanthine--guanine phosphoribosyl transferase (cho/hgprt) system. dose--response relationships of cytotoxicity and mutagenicity are presented for two alkylsulfates [dimethylsulfate (dms), diethylsulfate (des)] and three alkyl alkanesulfonates [methyl methanesulfonate (mms), ethyl methanesulfonate (ems), and isopropyl methanesulfonate (ipms)]. under ... | 1978 | 207981 |
| mutagenesis of chinese hamster cells in vitro by combination treatments with methyl methanesulfonate and n-acetoxy-2-acetylaminofluorene. | mutational synergism was examined in chinese hamster v79 cells exposed to methyl methanesulfonate followed by n-acetoxy-2-acetylaminofluorene (acaaf) at different time intervals. treatment with 500 micron methyl methanesulfonate resulted in 95% survival of cloning ability and induced approximately 4 azaguanine-resistant mutants/10(5) survivors. seven micron acaaf produced 10 times as many mutants, and the survival was 7%. lethal synergism was observed for methyl methanesulfonate treatments follo ... | 1978 | 208770 |
| chinese hamster lung cell polysomes direct the synthesis of a single molecular weight species of procollagen alpha chains. | polysomes prepared from cultured chinese hamster lung cells direct the synthesis of procollagen alpha chains in an heterologous cell-free system containing the postribosomal supernatant fraction prepared from wheat germ. total protein synthesis requires both subcellular components and an exogenous energy source, and is inhibited by the antibiotics puromycin and aurin tricarboxylic acid. the ratio of collagenase-digestible to nondigestible material produced depends upon the wheat germ and not the ... | 1978 | 209044 |
| localization of the binding site for cell attachment in the alpha1(i) chain of collagen. | certain cells such as cho (chinese hamster ovary) and fibroblasts attach to a substrate of type i collagen via proteins that link the cell surface to collagen. serum contains a glycoprotein, c-cap (collagen cell attachment protein), that can mediate this adhesion. previously, we established that alpha1(i)-cb7 (cyanogen bromide peptide 7), which lies within residues 552 to 822 of collagen, contains a major binding site for c-cap(alpha1(i)-cb7 has been renumbered to account for an additional tripl ... | 1978 | 209046 |
| aanlysis of dcmp deaminase and cdp reductase levels in hamster cells infected by herpes simplex virus. | several enzymatic activities involved in the biosynthetic pathways of nucleotides, including thymidine kinase, which has been used as a biochemical marker in studies of gene transfer, are induced by herpes simplex virus (hsv). the utility of additional markers prompted us to reanalyze the effects of hsv infection on the activities of two other enzymes for which direct selective methods can be devised: dcmp deaminase and cdp reductase. for this purpose, mutant chinese hamster (la1) cells devoid o ... | 1978 | 209209 |
| molecular dosimetry of the chemical mutagen ethyl methanesulfonate in escherichia coli and in v-79 chinese hamster cells. | 1978 | 209321 | |
| dose-rate effects of ethyl methanesulfonate on survival and mutation induction in cultured chinese hamster cells. | the dose-rate effects of ethyl methanesulfonate (ems) on the survival and induction of mutations in chinese hamster don cells were investigated. the most effective time of exposure to ems for reducing the surviving fraction of cells was 4 h, shorter and longer exposure times being less effective. the threshold or minimal concentration of ems giving a surviving fraction of 0.5 was 0.05 mg/ml. the minimal effective time of exposure to ems for cell death was 1 h. corrected survival curves showed th ... | 1978 | 209325 |
| homologous genes for enolase, phosphogluconate dehydrogenase, phosphoglucomutase, and adenylate kinase are syntenic on mouse chromosome 4 and human chromosome 1p. | it is possible to generate interspecific somatic cell hybrids that preferentially segregate mouse chromosomes, thus making possible mapping of mouse genes. therefore, comparison of the linkage relationships of homologous genes in man and mouse is now possible. chinese hamster x mouse somatic cell hybrids segregating mouse chromosomes were tested for the expression of mouse enolase (eno-1; ec 4.2.1.11, mckusick no. 17245), 6-phosphogluconate dehydrogenase [pgd; ec 1.1.1.44, mckusick no. 17220], p ... | 1978 | 209463 |
| new region of the simian virus 40 genome required for efficient viral transformation. | viable mutants of simian virus 40 with deletions in three regions of the virus genome (map coordinates 0.21-0.17, 0.59-0.54, and 0.67-0.74) have been tested for their ability to transform rat fibroblasts to anchorage independence. only those mutants whose deletions occur between 0.59 and 0.55 in the proximal part of the early region are defective in transforming ability. the most severely defective of these transform with less than one-hundredth the efficiency of wild type. they retain their def ... | 1978 | 209467 |
| reexpression of hprt activity following cell fusion with polyethylene glycol. | polyethylene glycol-1000 (peg-1000) induced fusion of hprt (e.c. 2.4.2.8) deficient chinese hamster cells with alpha-galactosidase a (e.c. 2.3.1.22) deficient cells from a patient with fabry's disease yielded hybrids which contained both human and hamster hprt, g6pd (e.c. 1.1.1.49), and aprt (e.c. 2.4.2.7) and chinese hamster alpha-galactosidase b. thus peg-1000 mediated somatic cell fusion led to reexpression of chinese hamster hprt. it did not restore the expression of human alpha-galactosidas ... | 1978 | 209782 |
| alteration in morphology of chinese hamster ovary cells by ni3s2 and dibutyryl camp. | 1978 | 210534 | |
| cyclic amp and insulin release. | the role of cyclic adenosine-3',5'-monophosphate (camp) for insulin secretion has been investigated. in isolated islets of langerhans from the rat, glucose increases camp concomitant with insulin secretion. stimulation of these two parameters is likewise reversible in parallel. the minimal and maximal concentrations of glucose eliciting camp and insulin responses are similar. isomers and epimers of glucose influence insulin and camp in a parallel fashion as do sulfonylurea compounds (tolbutamide ... | 1977 | 210617 |
| acid glycohydrolase in chinese hamster with spontaneous diabetes. iii. line-dependent variance. | 1990 | 210809 | |
| shedding of the glycoprotein from vesicular stomatitis virus-infected cells. | in a culture of chinese hamster ovary cells infected with vesicular stomatitis virus, there is specific shedding of viral antigens into the medium. this shedding appears to be unrelated to progeny formation or to cell lysis. although all five of the virus-specific proteins are detected in the extracellular soluble fraction, the major antigen is the gs protein. this protein has a molecular weight of 54,000. indirect analysis of the content of sialic acid as well as peptide analysis of the gs and ... | 1978 | 211264 |
| conditions necessary for quantifying ethyl methanesulfonate-induced mutations to purine-analogue resistance in chinese hamster v79 cells. | we have investigated conditions necessary to quantify the relationship between exposure to a mutagen, ethyl methanesulfonate (ems), and the frequency of mutation induction at the hypoxanthine-guanine phosphoribosyl transferase locus in v79 cells. maximal expression of potential mutants has been achieved by either subculturing at fewer than 5 x 10(5) cells/100-mm dish at 2-day intervals or by daily feeding of cultures. an expression period of 5 days (measure from 1 day after the initiation of tre ... | 1988 | 211407 |
| assignment of the receptor for ecotropic murine leukemia virus to mouse chromosome 5. | the gene for the receptor for ecotropic murine leukemia virus (rev) has been assigned to mouse chromosome 5. this determination was made possible by an analysis of somatic cell hybrids between mouse and chinese hamster cells. the parents of these hybrids were a/hej or mus poschiavinus peritoneal exudate cells or balb/c primary embryo fibroblasts and e36, a chinese hamster lung fibroblast deficient in hypoxanthine guanine phosphoribosyltransferase. segregation of mouse chromosomes in these hybrid ... | 1978 | 212501 |
| cytogenetic studies of a simian virus 40 temperature-sensitive mutant-transformed chinese hamster cell clone at the permissive and nonpermissive temperature. | a clone of chinese hamster embryo cells transformed by tsa58, the temperature-sensitive mutant of simian virus 40, was analyzed for chromosome abnormalities at the permissive temperature (37 degrees c) and nonpermissive temperature (40.5 degrees c). trypsin-giemsa-banded metaphases were analyzed 1 week after the temperature shift. the metaphases from cells at both temperatures were pseudodiploid, with numerous chromosome changes primarily affecting chromosomes no. 1 and 2. other chromosomes (no. ... | 1978 | 212571 |
| simian virus 40 a gene function: dna content analysis of chinese hamster cells transformed by an early temperature-sensitive virus mutant. | replication of two chinese hamster embryo cell lines transformed by an early temperature-sensitive mutant of simian virus 40, tsa58, was examined by flow microfluorometry and autoradiography of [3h]thymidine-labeled cells in order to determine whether transformed cell dna synthesis is initiated by the virus a gene. at the permissive temperature (37 degrees), cells transformed by the mutant were like the wild-type virus transformants in appearance, colony-forming ability, high saturation density, ... | 1978 | 212747 |
| a herpes simplex virus 1 integration site in the mouse genome defined by somatic cell genetic analysis. | transfection experiments with hsv 1 in which one uses herpes simplex virus (hsv) thymidine kinase (tk) as a selectable prototrophic marker yield two classes of transformed cells: stable and unstable. in this report, we test the hypothesis that the stability phenotype can be explained by virus genome integration into a recipient cell chromosome. the method of analysis is by means of somatic cell genetics. we have isolated a series of microcell hybrids between a tk- chinese hamster cell line and a ... | 1978 | 214240 |
| comparison of the interaction of mono- and oligovalent ligands with cholera toxin. demonstration of aggregate formation at low ligand concentrations. | the stimulation by cholera toxin of adenylate cyclase in chinese hamster ovarian cells could be inhibited by various ligands. the latter have been shown to contain the structural oligosaccharide entities required for binding to cholera toxin, established as galbeta1 leads to 3galnacbeta1 leads to 4gal3 comes from 2alphaneuac. the different inhibitory potency of the ligands thereby correlates with the size of the aggregates formed with the toxin, which in turn depends on the valency of the ligand ... | 1986 | 214384 |
| growth arrest of chinese hamster ovary cells in serum-free medium: changes in cell morphology and the intracellular and prostaglandin-induced levels of cyclic amp. | when chinese hamster ovary (cho) cells are shifted from medium which contains serum into serum-free medium, they complete one cell doubling and arrest in the g1 phase of the cell cycle. during the first 72 hr of arrest, there is little change in intracellular adenosine 3':5'-phosphate (camp) level, and the cells retain their usual epithelial-like morphology. after 96 hr, the camp level doubles, the magnitude of the prostaglandin e1-induced changes in camp increases threefold, and the cells conve ... | 1978 | 214460 |
| cyclic amp-dependent regulation of ornithine decarboxylase activity in chinese hamster ovary cells maintained with a salts/glucose medium. | ornithine decarboxylase activity (odc) increased about 7 fold 6--8 h following 10mm asparagine (asn) addition to confluent cultures that had been previously serum deprived and then placed in a salts/glucose medium. optimal concentrations of dibutyryl camp (db camp) when incubated with the asn caused up to a 50 fold increase in the activity of this enzyme after 7--8 h. the enhancement of odc activity by asn and db camp was not sensitive to continuous (0--7 h) treatment with actinomycin d but simi ... | 1986 | 214473 |
| in vitro assay for tumor promoters and anti-promoters. | tumor promoters and anti-promoters have been shown to modify the induction of ornithine decarboxylase, the production of plasminogen activator, and the recovery of induced mutations. data were presented to show that the recovery of mutagen-induced ouabain-resistant mutations in cultured chinese hamster cells is increased with a tumor-promoter treatment and reduced by anti-promoter treatments. the results suggest that many induced mutations can either be repressed or derepressed by promoters or a ... | 1986 | 214506 |
| characterization of two adenosine 3':5'-phosphate-dependent protein kinase species from chinese hamster ovary cells. | chinese hamster ovary cells exhibit several characteristic morphological and physiological responses upon treatment with agents which increase the intracellular level of adenosine 3':5'-phosphate (cyclic amp). to better understand the mechanism of these cyclic amp-mediated responses, we separated two cyclic amp-dependent protein kinases (atp:protein phosphotransferase, ec 2.7.1.37) (protein kinase i and protein kinase ii) from the cytosol of chinese hamster ovary cells by deae-cellulose chromato ... | 1986 | 215211 |
| changes in plasma membrane and microfilaments accompanying morphologic differentiation in chinese hamster ovary (cho) cells. | 1984 | 215421 | |
| localization of a gene for human alpha-galactosidase b (= n-acetyl-alpha-d-galactosaminidase) on chromosome 22. | the localization of the structural gene for human alpha-galactosidase b (= n-acetyl-alpha-galactosaminidase) was investigated by means of man-chinese hamster and man-mouse somatic cell hybrids. the hybrid clones were analyzed for chromosomes and for a large number of known enzyme markers. the lysates of the hybrid cells were treated with sepharose-coupled antihuman alpha-galactosidase b and the activity of the adsorbed enzyme was measured on the sepharose beads as n-acetyl-alpha-galactosaminidas ... | 1978 | 215508 |
| quantitative analyses of radiation- and chemical-induced lethality and mutagenesis in chinese hamster ovary cells. | 1981 | 216050 | |
| acid glycohydrolase in chinese hamster with spontaneous diabetes. iv. diabetes- and line-dependent variation in plasma enzyme activity. | the activity of five glycohydrolases was measured in the plasma of chinese hamsters from eight highly inbred lines in the upjohn colony. the diabetic animals showed elevated activities of plasma beta-d-galactosidase, n-acetyl-beta-d-glucosaminidase and n-acetyl-beta-d-galactosaminidase but similar activities of plasma alpha-d-glucosidase and alpha-d-galactosidase to the nondiabetic animals. line-specific variation was observed in all five enzymes and anomalies were especially evident in n-acetyl ... | 1982 | 216599 |
| genetic and biochemical studies with the adenosine analogs toyocamycin and tubercidin: mutation at the adenosine kinase locus in chinese hamster cells. | the pyrrolopyrimidine nucleosides toyocamycin and tubercidin show several unique features of growth inhibition in chinese hamster ovary (cho) cells. stable mutants which are more than 600-fold resistant to these drugs are obtained in cho cells at a strikingly high frequency of approximately 10(-3), in the absence of mutagenesis. the mutants resistant to toyocamycin (toyr) and tubercidin (tubr) exhibit similar cross-resistance patterns to the two selective drugs as well as to adenosine and 6-meth ... | 1981 | 217113 |
| lipid-saccharide intermediates and glycoprotein biosynthesis in a temperature-sensitive chinese hamster cell mutant. | the characterization of a temperature-sensitive chinese hamster cell mutant has been continued with the aim of localizing the apparent defect in glycoprotein synthesis (tenner et al., '77). although the mutation is lethal, a demonstration of the ability of the mutant cells to support proliferation of mengo virus at the nonpermissive temperature indicates that the general metabolic processes of the cells remain intact at a time when glycoprotein synthesis is severely depressed. a quantitative stu ... | 1979 | 217883 |
| study on the mutagenicity of conjugated estrogens in human, animal and bacterial systems. | conjugated estrogens were studied for mutagenicity (and implied carcinogenicity) in two strains of s. typhimurium, two normal and three neoplastic human lymphoid cell lines (the latter from burkitt's lymphoma patients) in cell culture and a chinese hamster cell line in diffusion chambers implanted into mice. no significant increase in mutation rate or chromosome aberrations were noticed after exposure to conjugated estrogens. | 1978 | 217940 |
| binding site on macrophages that mediates uptake and degradation of acetylated low density lipoprotein, producing massive cholesterol deposition. | resident mouse peritoneal macrophages were shown to take up and degrade acetylated (125)i-labeled low density lipoprotein ((125)i-acetyl-ldl) in vitro at rates that were 20-fold greater than those for the uptake and degradation of (125)i-ldl. the uptake of (125)i-acetyl-ldl and its subsequent degradation in lysosomes were attributable to a high-affinity, trypsin-sensitive, surface binding site that recognized acetyl-ldl but not native ldl. when (125)i-acetyl-ldl was bound to this site at 4 degre ... | 1979 | 218198 |
| regional localization of the gene for human phosphoribosylpyrophosphate synthetase on the x chromosome. | sixty-eight independent hybrid clones were isolated after irradiated normal human lymphocytes were fused with chinese hamster fibroblasts lacking hypoxanthine-guanine phosphoribosyltransferase activity. the cells were grown under selective conditions requiring retention of the x chromosome-linked locus for human hypoxanthine-guanine phosphoribosyltransferase. the frequency and patterns of cotransference of human phosphoribosylpyrophosphate synthetase with the selected marker and with additional ... | 1979 | 218284 |
| an analysis of concanavalin a-mediated agglutination in two chinese hamster ovary subclones whose surface phenotypes respond to maintenance in medium supplemented with dibutyryl cyclic amp. v. biochemical composition of the plasma membrane. | we have used two chinese hamster ovary subclones whose surface phenotype has been extensively investigated with regard concanavalin a-mediated cell-cell agglutination and concanavalin a-induced receptor site clustering to investigate what changes in membrane composition, if any, can be correlated with the concanavalin a-detected changes in surface phenotype. these cell clones are uniquely disposed for this purpose since maintenance of the cells under different growth conditions produces changes ... | 1978 | 218629 |
| detachment variants of chinese hamster cells. hyaluronic acid as a modulator of cell detachment. | 1979 | 218830 | |
| biosynthesis of lipid-linked oligosaccharides. isolation and structure of a second lipid-linked oligosaccharide in chinese hamster ovary cells. | previous work has shown that vesicular stomatitis virus-infected chinese hamster ovary cells contain a major high molecular weight lipid-linked oligosaccharide which is transferred en bloc to protein during the formation of the asparagine-linked complex-type oligosaccharides of the vesicular stomatitis virus g protein (tabas, i., schlesinger, s., and kornfeld, s. (1978) j. biol. chem. 253, 716-722). we now report the characterization of a second, lower molecular weight lipid-linked oligosacchari ... | 1979 | 218953 |
| an analysis of con a-mediated agglutination in a chinese hamster ovary subclone which responds morphologically to growth in dibutyryl cyclic amp. iii. the role of microvilli in the agglutination process. | we have used the h-7w subclone of a chinese hamster ovary cell line (k1) to investigate the role of cell surface architecture (specifically microvilli, blebs, and sheets) in determining the relative agglutinability of a cell line with con a. our evidence clearly demonstrates that no specific, immediately recognizable surface architecture is associated with the agglutinable or non-agglutinable phenotype. our data suggest that the expression of microvilli on the cell surface is neither necessary t ... | 1985 | 218980 |
| genes controlling receptors for ecotropic and xenotropic type c virus in mus cervicolor and mus musculus. | gene loci controlling cell surface receptors for murine leukemia virus were studied by using murine x chinese hamster hybrid cells. hybrids which exclusively segregate murine chromosomes were made by fusing mus cervicolor and mus musculus lymphocytes to hamster fibroblasts. sensitivity to moloney murine leukemia virus infecotion and specific binding of the envelope glycoprotein of rauscher murine leukemia virus (gp70) cosegregate and isozyme analysis show an association with chromosome 5 in both ... | 1979 | 219245 |
| phosphorylation of t-antigen and control t-antigen expression in cells transformed by wild-type and tsa mutants of simian virus 40. | chinese hamster lung (chl) cells transformed by wild-type simian virus 40 (cell line chlwt15) or transformed by the simian virus 40 mutants tsa30 (cell lines chla30l1 and chla30l2) or tsa239 (cell line chla239l1) were used to determine the rates of turnover and synthesis of the t-antigen protein and the rate of turnover of the phosphate group(s) attached to the t-antigen at both the permissive and restrictive temperatures. the phosphate group turned over several times within the lifetime of the ... | 1979 | 219256 |