bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibitory effects of anti‐tumor platinum compounds on DNA, RNA and protein syntheses in mammalian cells in vitro
Authors: Harder Harold C. , Rosenberg Barnett 
Published: February 2007

AbstractThe inhibitory effects of anti‐tumor, bacterial filament forming platinum compounds, Cis‐Pt(II) (NH3)2Cl2 (A), Cis‐Pt(IV) (NH3)2Cl4 (B), and Pt(II) (NH2)2(CH2)2Cl2(C) on DNA, RNA and protein syntheses was measured by the incorporation of 3H‐thymidine, 3H‐uridine, and 3H‐L‐leucine, respectively, into an acid‐insoluble polymer in human amnion AV3 cells. Compound A, the most effective tumor‐inhibiting platinum compound, was shown to selectively inhibit DNA synthesis below 5μM and to inhibit 3H‐thymidine incorporation more rapidly than 3H‐uridine or 3H‐leucine incorporation at 25μM. Like A, compounds B and C were also shown to inhibit all three processes after a 24‐hour period of treatment at 25μM. A correlation was established between the relative anti‐tumor effectiveness of compounds A, B, and C and the extent of their inhibitory effects. On the other hand, two non‐tumor‐inhibiting platinum compounds, [Pt(II) (NH3)4]Cl2 (D) and Trans‐Pt(IV) (NH3)2Cl4 (E) had no inhibitory effects, except compound E, which exhibited a rapid initial inhibition of 3H‐L‐leucine incorporation at 100μM. The inhibition of 3H‐thymidine incorporation into cells pretreated 4 h with 5μM of compounds A, B, and C was shown to be irreversible. Finally the inhibition of the incorporation of 3H‐thymidine into DNA by A was shown not to be caused by the inhibition of the uptake of the tracer into the acid‐soluble pool. A number of possible explanations for the greater sensitivity of DNA synthesis and the sequential inhibition of DNA, RNA and protein synthesis at higher concentrations are suggested.
Upper respiratory tract tumors induced in syrian hamsters by N‐methyl‐N‐nitrosourea
Authors: Herrold Katherine McD. 
Published: February 2007

AbstractSyrian hamsters were treated weekly for 2 1/2 months by intratracheal instillation of N‐nitroso‐N‐methylurea (NMU). All the animals, with the exception of one that survived to 11 months of age, were killed between 5 and 7 months because of severe respiratory insufficiency. Tumors, often multicentric in origin and frequently at different sites, developed in the nasopharyngeal tube, pharynx, larynx, trachea, bronchi, esophagus and forestomach. Histologically the tumors were epidermoid carcinomas. No distant metastases were observed.The results indicate that NMU exerts a strong local carcinogenic action when applied topically to the mucosa of the upper respiratory tract of Syrian hamsters. The wide spectrum of lesions, benign and malignant tumors, that occur following parenteral administration of NMU were not seen.
Effect of prolonged cultivation of SV40‐transformed mouse cells in bromodeoxyuridine or pretreatment with mitomycin C on rescue of SV40
Authors: Dubbs D. R. , Kit Saul 
Published: February 2007

AbstractA series of clonal lines (mKS‐U) of mouse kidney cells transformed by UV‐irradiated SV40 have been propagated serially in medium containing 5‐bromodeoxyuridine (dBU). Most of the mKS‐U lines became resistant to dBU during serial passage and became deficient in thymidine (dT) kinase activity. The dT kinase‐deficient mKS‐U lines were unable to grow in medium containing HATG (10−4 M hypoxanthine, 10−5 M aminopterin, 4 × 10−5 M thymidine, and 10−5 M glycine; Littlefield, 1965) because they were unable to utilize exogenous thymidine as a source of thymidylate when de novo synthesis of thymidylate was blocked by aminopterin. Growth in dBU medium did not increase the buoyant density of the DNA of mKS‐U lines deficient in dT kinase activity, demonstrating that dBU was not incorporated into the DNA of the cells. These observations show that a heritable change had occurred in the dBU‐grown mKS‐U cell lines. However, two dBU‐adapted cell lines, mKS‐U1 (BU) and mKS‐U2 (BU), did retain appreciable dT kinase activity even after 97 and 98 passages in dBU. The DNAs from mKS‐U1 (BU) and mKS‐U2 (BU) grown in dBU had buoyant densities greater than those of the DNAs from mouse cells grown in medium lacking dBU and the mKS‐U1 (BU) and mKS‐U2 (BU) lines were able to grow normally in HATG medium.Serial passage of poor, average, or good yielder transformed lines in dBU did not significantly change the frequency of induction of SV40 in fusion experiments with African green monkey kidney (CV‐1) cells. However, the SV40 rescued in fusion experiments with two poor yielders after serial passage in dBU tended to produce larger plaques than those rescued prior to passage in dBU. Serial passage in dBU did not permit rescue of SV40 from heterokaryons of the rare yielders or non‐yielders.The SV40 antigen was present in all the cell lines, even after prolonged cultivation in dBU, indicating that the SV40 genome was retained.Pretreatment of mKS‐U lines with mitomycin C prior to fusion with CV‐1 cells did not alter the virus yield from a good yielder, mKS‐U13, after fusion with CV‐1, and did not permit rescue of SV40 from rare or non‐yielder lines.
Possible association of embryonal antigen(S) with several primary 3‐methylcholanthrene‐induced murine sarcomas
Authors: Brawn R. James 
Published: February 2007

AbstractLymph‐node cells from pregnant BALB/c mice multiparous by BALB/c males, as compared to lymph‐node cells from age‐matched virgin female BALB/c mice, inhibit the in vitro colony formation of several lines of primary syngeneic strain female 3‐methyl‐cholanthrene‐induced murine sarcomas. Colony formation of normal female BALB/c or female BALB/c x C3H fibroblastic cells is not similarly inhibited.
Further studies on tumour‐producing activity in adult mice by embryonic tissue cultures exposed to a virus and grafted before manifestation of morphologic transformation
Authors: Kryukova I. N. , Obukh I. B. , Biryulina T. I. , Babkova O. V. 
Published: February 2007

AbstractExperiments were carried out to test the possibility of tumour production in adult recipients of different mouse strains by syngeneic embryonic tissue cultures exposed to, and not transformed by several oncogenic viruses. Tumour‐producing effect of embryonic tissue cultures exposed to C‐Z strain of RSV was observed in 100% of A, C3H‐H2p, AKR, C57BL/Sn, CC57W and in a small proportion of CC57BR mice, but not in B10.D2 and BALB/c mice. However, introduction of infected embryonic tissue cultures, originating from the resistant strains of mice, into F1 hybrids between the opposite strains resulted in tumour production. It was demonstrated that resistance to tumour production of the three strains mentioned above was not mediated by the strong immune reaction against the cells introduced.Tumour‐producing effect by infected but untransformed cells was also seen with the C‐Z strain in hamsters, with the S‐R strain of RSV in mice, and with the 5D strain in hamsters but not in mice.Attempts to produce tumours in mice by the introduction of syngeneic embryonic tissue culture exposed to SV40 and neurotropic strain (WSN) of influenza A viruses were negative.
On the surface structure of murine ascites tumors. I. Interactions with various phytoagglutinins
Authors: Tomita Motowo , Osawa Toshiaki , Sakurai Yoshio , Ukita Tyunosin 
Published: February 2007

AbstractPhytoagglutinins originating from various plants agglutinated murine tumor cells and erythrocytes to varying degrees; some strongly, some moderately, and some not at all. The agglutinability of Yoshida sarcoma cells (rat ascites tumor) by various phytoagglutinins was essentially similar to that of ascites hepatoma 66 cells (rat ascites tumor), and similarity of agglutinability was also found between Ehrlich ascites carcinoma cells and leukemia 1210 cells, both of which were of murine origin. Since the phytoagglutinins react with the corresponding binding sites of cell surfaces in a similar manner to antibodies, the binding sites could be specified by the inhibition of the bindings after the addition of mono‐ or disaccharides. The treatment of Yoshida sarcoma cells with chemical reagents, hydrolytic enzymes or heat changed their agglutinability against the agglutinins. The extent to which their agglutinability was changed by these treatments, however, differed according to the kind of agglutinin used.
Cell‐mediated immunity against antigens common to human colonic carcinomas and fetal gut Epithelium
Authors: Hellström Ingegerd , Hellström Karl Erik , Shepard Thomas H. 
Published: February 2007

AbstractBlood lymphocytes from human patients with adenocarcinomas of the colon inhibited colony formation of plated cells from colon carcinomas, but not of cells from normal adult colon mucosa, as compared to control lymphocytes from patients who did not have cancer or who had neoplasms other than colon carcinomas. Lymphocytes from patients with colon carcinomas also inhibited plated fetal gut and liver epithelial cells, while they did not inhibit fetal kidney cells. The data thus indicated that colon carcinomas, fetal gut and fetal liver cells have an antigen in common, absent from adult colon and fetal kidney, and that lymphocytes from patients with colonic carcinomas are immune to that antigen.
Demonstration of antigens related to colonic cancer in the human digestive system
Authors: Martin F. , Martin M. S. 
Published: February 2007

AbstractHeteroimmunization of rabbits with saline or perchloric extracts of colonic cancers permits the detection of two cancer‐related antigens. These antigens may be demonstrated, by direct precipitin reaction, in saline extracts of colonic or rectal adenocarcinomata, of some gastric cancers, and of foetal gut, but not in saline extracts of the non‐cancerous adult digestive system. However, precipitin‐inhibition reaction shows these antigens in perchloric extracts of non‐cancerous colonic mucosa but their concentration is much weaker than in intestinal tumours. Detection of a small amount of these antigens in non‐cancerous colonic mucosa implies that they are cancer‐related, but not cancer‐specific. Identity of one of the antigens with Gold's carcinoembryonic antigen is discussed.
The formation of variants with a reversion of properties of transformed cells. V. Reversion to a limited life‐span
Authors: Rabinowitz Zelig , Sachs Leo 
Published: February 2007

AbstractIt has been shown that hamster cells transformed after treatment with the chemical carcinogen dimethylnitrosamine (DMNA) in which the transformed state has become a hereditary cellular property, can, like cells transformed by polyoma virus, produce a high frequency of variants with a reversion of properties of transformed cells. In contrast to variants from polyoma‐transformed cells, 81–93% of the variants from DMNA‐transformed cells, and from cells transformed by benzo (a) pyrene or X‐irradiation had again, like normal cells, acquired a limited life‐span in vitro. This termination of life‐span was intracellularly determined. The escape from the limited life‐span by some of these variants was due to a re‐reversion from the reverted to the transformed state. The results suggest that the persistence of the viral genome in variants from polyoma‐transformed cells prevented their reverting to a limited life‐span.
Cellular DNA synthesis in productive infection with adenoviruses
Authors: Takahashi Michiaki , Baba Koichi , Minekawa Yoshiichi 
Published: February 2007

AbstractThe effect of adenoviruses on cellular DNA synthesis in productive infection of hamster kidney cells and human embryonic lung cells was studied.(1) Treatment with 5‐fluorouracil (FU) strongly reduced incorporation of 3H‐dT into DNA of uninfected hamster kidney cultures. Under such conditions, the amount of incorporation of 3H‐dT into DNA in FU‐treated Ad5‐infected cultures was about one‐third of that observed in untreated ones. Analysis by DNA‐DNA hybridization revealed that the major proportion of newly synthetized 3H‐DNA was cellular between 16 to 32 h after infection in FU‐treated infected cultures. Synthesis of viral DNA and infectious virus was slightly delayed and reduced in FU‐treated cells.(2) With the aim of keeping the specific activities of 3H‐dT derivatives in acid‐soluble pools in cells as constant as possible, long‐term labelling of DNA with 3H‐dT after infection was carried out, in the presence of aminopterin, hypoxanthine and glycine to prevent endogenous biosynthesis of thymidylic acid. Incorporation of 3H‐dT into cellular DNA was much greater in infected than in uninfected cultures after labelling for 24 h. These results strongly suggest that cellular DNA synthesis was induced in productive infection of hamster kidney cells by Ad5.(3) Infection of monolayer cultures of human embryo lung (HEL) cells with adenovirus types 2, 3, 4, 5 and 12 (Ad2, Ad3, Ad4, Ad5 and Ad12) resulted in productive infection with delayed cytopathic effect (CPE).3H‐dT uptake into DNA was stimulated in contact‐inhibited HEL cells by infection. Apparent increase in incorporation of 3H‐dT into cellular DNA was detectable for a long period in infected cultures, suggesting that induction of cellular DNA synthesis took place by infection. Thus the time of appearance of CPE seems to be correlated with the period during which induction of cellular DNA synthesis is detectable.
Studies on the immune responses of BALB/c mice during tumor induction by mineral oil
Authors: Kripke Margaret L. , Weiss David W. 
Published: February 2007

AbstractThe immune responses to a number of different antigens were tested under the influence of mineral oil treatment in two strains of mice: BALB/c, which is susceptible to oncogenesis by intraperitoneal administration of oil, and C57Bl, which is resistant. A limited, but general, immunological depression was elicited by the oil treatment in the BALB/c, but not in the C57Bl, animals.Immunogenicity studies on tumors induced by mineral oil in BALB/c mice suggest that this category of neoplasms also possesses tumor‐associated antigenicity.The findings are discussed in relation to the role which may be played by dysfunction of the immune response in carcinogenic action.
Effect of 17‐β‐estradiol and testosterone on aryl hydrocarbon hydroxylase activity in mouse tissues in vivo and in cell culture
Authors: Nebert D. W. , Bausserman L. L. , Bates R. R. 
Published: February 2007

AbstractInitiation of skin tumors by 7,12‐dimethylbenz[a]anthracene is more effective during diestrus than during estrus and thus may be inhibited by estrogens. We therefore studied the effect of sex hormones on aryl hydrocarbon hydroxylase, an enzyme system which may be a common pathway in metabolizing both polycyclic hydrocarbons and steroids.1. The hydroxylase system is present in mouse skin and liver and is inducible by the administration of polycyclic hydrocarbons such as 3‐methylcholanthrene and 7,12‐dimethylbenz[a]anthracene. The control and inducible enzyme activities are slightly lower in castrated male mice which have received subcutaneous implants of 17‐β‐estradiol.2. In mouse fetal cell cultures, 17‐β‐estradiol in the growth medium prevents hydroxylase induction only at concentrations 6 to 60 times greater than the level of the polycyclic hydrocarbon inducer in the medium.3. In a cell‐free in vitro system, both 17‐β‐estradiol and testosterone competitively inhibit polycyclic hydrocarbon hydroxylation, even at levels of steroid that are lower than that of the polycyclic hydrocarbon substrate. With the hydroxylase system from mouse liver, lung, kidney, adrenal and skin in the cell‐free system, 17‐β‐estradiol is generally more inhibitory than testosterone. This difference in inhibition between an estrogen and an androgen may be related to sex differences in the metabolism of drugs and in the susceptibility to carcinogenesis by polycyclic hydrocarbons.
Azo‐Dye binding to proteins and detoxication of p. dimethylaminoazobenzene in mouse and hamster liver
Authors: Decloitre Françoise , Meunier Michèle 
Published: February 2007

AbstractWe studied azodye binding to proteins, and at the same time azoreductase and NADPH‐cytochrome c reductase activities in the liver of IC and C3H mice and hamsters fed DAB over a long period. Sensitivity of C3H mice to the toxic effects of DAB and resistance of IC mice and hamsters were confirmed by histological examinations. After 2–3 weeks of DAB feeding, the amount of protein‐bound azo‐dyes was three times higher in C3H mice than in IC mice. For hamsters, limited azo‐dye binding to proteins increased gradually up to 6 weeks, then remained nearly constant. In control animals azoreductase activity was five times higher in IC mice than in C3H mice; activity of hamsters was intermediate. NADPH‐cytochrome c reductase activity was nearly the same in all three groups, and was in no way related to azoreductase activity. The sensitivity of C3H mice to the toxic effects of DAB could be explained by their weak azoreductase activity and high level of azodye binding to proteins. On the contrary, high azoreductase activity in IC mice would allow detoxication of DAB and prevent or delay its toxic effects. Resistance of hamsters could be linked to the small amount of protein‐bound azo‐dye; yet, it cannot be explained by their weak azoreductase activity and probably depends on other metabolic processes, which have been considered.
A prospective trial of the tnm classification of breast cancer by the regional cancer treatment centres in Ontario, 1960–1964
Authors: Mackay E. N. , Sellers A. H. 
Published: February 2007

AbstractAs its contribution to the 1960–64 clinical trial of the TNM Classification of breast cancer, The Ontario Cancer Treatment and Research Foundation reviewed in detail the distribution and 5‐year survival of 1,846 female patients classified according to TNM criteria. While further consideration of some aspects is required (for example, differentiation between skin infiltration and skin ulceration in T3, and the possible reallocation of certain T4 and N3 categories in stage IV), the UICC criteria in general appeared reasonably homogeneous within T and N categories, and sufficiently distinctive between categories. Summary tables showing statistically significant findings are given; basic tables for comparison or pooling with other series are available on request. The Ontario experience is strongly in favour of the general principles of the classification.
A dilute agar colony inhibition (CI) test for studying cell‐mediated immune responses against tumor cells
Authors: Heppner G. H. , Kopp J. S. 
Published: February 2007

AbstractA modification of the Hellström method for measuring cell‐mediated immunity to tumor‐associated antigens is described using mouse mammary tumors as a model. Target tumor cells are incubated with lymphocytes for 1 h and then cloned by the dilute agar method. The number of surviving cell colonies following incubation with immune lymphocytes is compared to the number of surviving tumor cell colonies incubated with control lymphocytes. Significant inhibition is obtained with as few as 10 immune lymphocytes for every target cell. Serum from immune animals can be shown capable of blocking lymphocyte‐mediated inhibition of tumor colony formation. The data obtained with this method are very similar to those obtained with the Hellström test. The advantages and disadvantages of the modification, as compared to the Hellström test, are discussed.
Properties of transformed hamster cells containing sv40 tumor antigen in the cytoplasm
Authors: Richardson Linda S. , Butel Janet S. 
Published: February 2007

AbstractThe properties of hamster cells containing SV40 tumor (T) antigen in the cytoplasm, rather than the nucleus, were determined. Eight cell lines were established from eight tumors induced by hamster embryo fibroblasts transformed in vitro by PARA (2cT)‐adenovirus 7. Six cell lines contained only cytoplasmic SV40 T‐positive cells while two were a mixture of nuclear T‐positive and cytoplasmic T‐positive cells. All the cell lines contained SV40 S antigen, all caused the production of SV40 T antibody in vivo, and four elicited the production of adenovirus T antibody. The cell lines seem to have acquired an infinite life span in vitro. The localization of T antigen apparently can be a stable phenomenon because five of the cell lines have retained T antigen exclusively in the cytoplasm for over 40 passages in tissue culture. The cytoplasmic T antigen could be detected by complement fixation in addition to immunofluorescence. Cytoplasmic T‐positive cells were readily transplantable in vivo and contained SV40 TSTA demonstrable by both immunogenicity and immunosensitivity procedures. Two of the three cytoplasmic variants of PARA appear to be weakly oncogenic in newborn hamsters.
Effect of adenovirus type 12 on tumor induction by SV40 and para (defective SV40)
Authors: Butel Janet S. , Melnick Joseph L. , Tevethia Satvir S. 
Published: February 2007

AbstractPARA (defective SV40) was transcapsidated from adenovirus type 7 to the highly oncogenic Huie strain of adenovirus type 12. This transfer of PARA to adenovirus 12 was found to hasten the appearance of SV40‐type tumors in hamsters inoculated as newborns; the tumors induced by the PARA‐adenovirus 12 population had a latent period of 5–7 weeks. All the induced tumors contained SV40 and adenovirus tumor antigens. Parental SV40 and PARA‐adenovirus 7 did not induce any tumors in the same time period. Artificial mixtures of adenovirus 12 and SV40 or adenovirus 12 and PARA‐adenovirus 7 did induce tumors with short latent periods (5–7 weeks). However, in contrast to tumors induced by PARA‐adenovirus 12, all the early appearing tumors induced by the mixtures of virus were, with one exception, devoid of SV40 tumor antigen and contained only adenovirus tumor antigen. Tumors induced by PARA‐adenovirus 12 carried SV40 transplantation antigen.
Distribution of intracisternal a‐particles in a variety of normal and neoplastic mouse tissues
Authors: Wivel Nelson A. , Smith Gilbert H. 
Published: February 2007

AbstractExamination of various normal and neoplastic tissues reveals the presence of intracisternal A‐particles in five strains of mice and their hybrids. Cell types derived from all three embryonic germ layers contain these particles, and their presence in gonadal tissue of both sexes suggests that vertical transmission can take place. Intracisternal A‐particles are found in most of the tissues known to support the replication of mouse leukemia viruses and mammary tumor virus. Further, they have been shown to coexist in the same cell with C particles and intracytoplasmic A‐particles (mammary tumor virus precursors). Although it has not been possible to demonstrate biological activity associated with intracisternal A‐particles, there is the possibility that they represent the partial gene expression of one of the known oncogenic RNA viruses, and as such serve as a marker for an incomplete replication cycle.
Immunofluorescent study of alpha‐foetoprotein (αfp) in liver and liver tumours. I. Technique of αfp localization in tissue sections
Authors: Engelhardt N. V. , Goussev A. I. , Shipova L. Ja. , Abelev G. I. 
Published: February 2007

AbstractSections of paraffin‐embedded tissue blocks fixed by ethanol/acetic acid were found to be very suitable for immunofluorescent (IF) study of αfp. In paraffin blocks the antigen was preserved for at least 1 year. It was possible to prepare serial sections for routine histological examination and simultaneous IF localization of several antigens practically in the same cells.Antibodies to αfp were obtained by glutaraldehyde immunosorbent technique. Their monospecificity was controlled by IF reaction on the αfp‐negative sections and by neutralization with pure αfp.To differentiate αfp localization due to passive serum uptake from specific sites of αfp production or storage, a simultaneous study of αfp and γ‐globulin γG distribution was performed. Only the structures containing αfp without γG were regarded as specifically connected with αfp metabolism. These were liver parenchyma cells in foetal and newborn liver and tumour cells in human primary liver carcinoma.