bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth of the SV40‐ADENO 7 hybrid virus in human diploid cells
Authors: Kutinová Luda , Vonka V. 
Published: February 2007

AbstractThe reproduction of SV40‐adeno 7 hybrid virus (SP 2) was studied in a human diploid cell strain (LEP). Both components of the hybrid virus, i.e. the true adeno 7 and the defective PARA carrying incomplete SV40 genome, gew well in this system. Their final titres were comparable to those observed in green monkey kidney (GMK) cells. Investigation of the interaction between adeno 7 and PARA in LEP cells, including the examination of plaque‐derived virus lines, revealed that in this system the adeno 7 virus grew without the helper effect of PARA; moreover, the presence of PARA did not significantly influence the growth characteristics of adeno 7 in LEP cells. PARA, although present in some preparations of SP 2 virus in quantities exceeding adeno 7, were found to be defective in LEP cells as well as in GMK cells. Their presence and titre in different SP 2 virus lines derived from LEP cells were dependent on the multiplicity of infection.
Occurrence of fetoprotein in patients with neoplasms and non‐neoplastic diseases
Authors: Masopust J. , Kithier K. , Rádl J. , Koutecký J. , Kotál L. 
Published: February 2007

AbstractSera from 248 patients, children and adults with various tumors, and from 484 patients with different non‐tumorous diseases, were examined for the presence of fetoprotein by immunochemical methods and specific anti‐fetal protein antiserum absorbed with serum of adult individuals. The results show that fetoprotein appears in two types of tumors only: 1) in hepatocellular carcinoma, and 2) in malignant undifferentiated teratoma. In other types of neoplasms including embryonal tumors composed of more or less differentiated tissue, as well as in cases of nephroblastoma, sympathicoblastoma, chorionepithelioma and dysgerminoma, fetoprotein was not detected in any patient. Fetoprotein can occur in the first year of life in some patients suffering from hepatitis or some other liver disease. However, its concentration is low and it has a tendency to disappear with the regression of the disease. Fetoprotein was not detected, however, in patients suffering from non‐malignant diseases, including hepatitis, after the first year of life.
The effect of halogenated nucleosides on the sensitivity of a mouse lymphoma P388F TO X‐rays and methyl methanesulphonate
Authors: Fox Margaret 
Published: February 2007

AbstractPopulations of the P388F mouse lymphoma were sensitized to the effects of X‐rays by prolonged culture in non‐toxic doses of 5‐iodo‐2'‐deoxyuridine and 5‐bromo‐2'‐deoxyuridine. A marked decrease in the ability of analogue‐exposed cells to recover from fractionated doses of X‐rays was found. Thus the mechanism of sensitization may be related to inhibition of repair mechanisms. Replicate cultures of the same populations did not show an increase in sensitivity to the monofunctional alkylating agent methyl methanesulphonate (MMS), which suggests that damage by X‐rays and MMS may be by different mechanisms in the cell line. The results would also suggest that the alkylation of DNA by MMS is not the only cytotoxic effect of this drug.
UICC standard reference samples of asbestos
Authors: Timbrell V. , Gibson J. C. , Webster I. 
Published: February 2007

ÉCHANTILLONS‐TYPES D'AMIANTE DE L'UICCA la suite des recommandations faites en 1964 par le Groupe de travail „amiante et cancer”︁ de l'UICC et dont l'application avait été examinée par un Comité spécial en 1965, des échantillons‐étalons des cinq principaux types d'amiante ont été préparés par des chercheurs d'Afrique du Sud et du Royaume‐Uni, avec l'aide des entreprises minières intéressées de divers pays.Plusieurs laboratoires en étudient actuellement les propriétés physiques et chimiques. Les échantillons (en sachets de plastique de 500 g ou moins) peuvent ětre obtenus sur demande à la Pneumoconiosis Research Unit, Johannesburg, Afrique de Sud, ou à la P. R. U. de Penarth, Royaume‐Uni.
Iron‐dextran induction of distant tumours in mice
Authors: Langvad E. 
Published: February 2007

AbstractThe systemic carcinogenicity of iron‐dextran has been investigated after single and repeated injections of Imferon in mice and rats. Systemic iron deposits induced by irondextran resulted in a stepwise development of reticulosarcomas. Such a histologic reaction, however, was not seen in relation to iron deposits following iron‐carbohydrate complex (Intrafer) administration. Distant tumours arising in the lymphoreticular structures showed a uniform latency in test and control mice, while tumours of other origin showed a prolonged latency as compared to such tumours in control animals. It is suggested, therefore, that iron‐dextran may act as a co‐carcinogenic factor in the case of lymphoreticular neoplasia, increasing host susceptibility to the oncogenic virus presumably present in both control and test animals. The non‐lymphoreticular distant and local tumours may stem from a different and direct carcinogenic action of iron since these tumours showed a prolonged latency and were seen after the administration of either iron‐dextran or iron‐carbohydrate complex.The results indicate an inconclusive dose‐response relationship, though no significant difference was found between tumour yield in the larger groups receiving 500 and 25 mg Fe…/kg body weight, the latter dose being within the therapeutic level on a comparative weight basis.
Pathogenesis of rous sarcoma virus in the chick embryo with particular reference to vascular lesions
Authors: Coates H. , Borsos T. , Foard M. , Bang F. B. 
Published: February 2007

Abstract1. Growth of strains of Rous sarcoma virus on the chorio‐allantoic membrane continues throughout the embryo's development, with some decrease in the rate of growth at the end. Susceptibility of the chorio‐allantoic membrane, as measured by the total number of lesions following a standard inoculum, was greatest at 11 to 13 days of incubation. The proportion of vascular pocks of the membrane was however much higher in embryos inoculated at 7 or 8 days of incubation.
Growth of virus in the chick embryo liver after intravenous inoculation was also continuous throughout incubation. Age of susceptibility, again measured by number of lesions, was however greatest at 8 to 10 days.
Examination of vascular lesions in the living embryo, and study of whole mounts stained by periodic acid‐Schiff method as well as of histological sections, all indicated that the vascular lesion was at least predominantly a localized neoplasm of the vascular endothelium. The early presence of PAS‐positive cells in the developing pock was demonstrated, an observation hitherto limited to tissue culture.
The presence of antibody to Rous virus in the yolk of the embryo was correlated with a decrease of vascular lesions following inoculation of 13‐day embryos but not ofj I‐day embryos.
Following intravenous inoculation, virus was probably limited to the initial area of infection during the first few days, but viremia was irregularly demonstrable from 3 days on.
In the discussion it is emphasized that tumors of the embryo or the chicken provoked by the Rous virus are primarily tumors of tissues derived from the mesoderm. This includes the capacity to cause vascular lesions. The production of avion lymphomatosis may well be an exception, but since the lymphatic tissue has not been clearly demonstrated to be of ectodermal origin, this remains an open question. Virus growth and tissue culture ‘ transformation ’ do occur in a variety of tissues.
Immunological study of leukemias in bald mice
Authors: de Pirosky Rosa Rabinovich 
Published: February 2007

AbstractA study of the antigenic relationship between four leukemias in the BALB strain has been carried out. These included a spontaneous leukemia and three induced by different exogenous agents such as Sarcoma 180, 32P, and human neoplastic tissue.Antisera were obtained by allogeneic hyperimmunization in Rockland inbred mice using fresh homogenates of BALB leukemic spleen and mesenteric lymph nodes. The four antisera with hemagglutinating titers between 1/1,280 and 1/5,120 and cytotoxic titers between 1/160 and 1/320, were absorbed by normal BALB cells until the titers fell below 1/10.These absorbed antisera possessed neutralizing activity against fresh leukemic cells, as demonstrated in tests with live challenges. However each antiserum proved to be active against all four leukemias while each of the leukemias could absorb the neutralizing activity of any antisera.These experiments only allowed the detection of one antigen in the four leukemias studied, no antigenic difference being observed among them by this technique.Taking into account the fact that the BALB strain of this laboratory has a spontaneous leukemia incidence of 15%, these results suggest that the exogenous agents which induced three of these leukemias acted by triggering a latent leukemogenic process.
Conversion Cellulaire Provoquée in vitro par le Virus du Sarcome Murin (Moloney). Analyse de la Courbe Dose‐Réponse
Authors: Bernard C. , Guillemain B. , Peries J. , Boiron M. 
Published: February 2007

AbstractAn analysis of mouse sarcoma virus (MSV, Moloney strain) titration curves, based on the focus‐forming activity described by Hartley and Rowe, confirms that Moloney leukaemia virus (MLV) acts as a „helper”︁ of MSV for focus initiation.However, viral stocks also seem to contain particles capable of initiating foci without the aid of MLV, as demonstrated by the linear relationship between the dilution and the number of foci when high dilutions were used.The possible application of this method for titrating MSV is discussed and some data are given concerning the origin of the virus (tumours or tissue culture supernatants) and the type of reactive cells.
Polyoma virus replication in ascitic cells
Authors: Nordenskjöld Bo 
Published: February 2007

AbstractSeveral ascitic tumors have been tested for polyoma sensitivity.Three tumors, one methylcholanthrene‐induced and two polyoma‐virus‐induced, were demonstrated to be sensitive to polyoma virus as judged by plaque titration, hemagglutination and fluorescent antibody assay.These determinants were correlated with the number of surviving cells and appearance of antiviral antibodies. The amount of virus produced and the number of infected cells found increased exponentially to reach a plateau about 50–100 hr post infection, after which the two respective counts either remained stationary or proceeded to fall.A reduction in virus recovery was paralleled by the appearance of antiviral antibodies in the serum. The total number of cells present in the peritoneal cavity remained stationary, or dropped after polyoma infection, suggesting the possibility that polyoma virus acted as an oncolytic agent.The high number of infected cells obtained at optimal times after polyoma exposure suggests the possibility that ascites tumors can be a useful routine tool for biochemical and other experiments where an abundant source of polyoma‐infected cells is needed.
Chromosome studies on cultured lymphoblast cell lines from cases of new guinea burkitt lymphoma, myeloblastic and lymphoblastic leukaemia and infectious mononucleosis
Authors: Tomkins G. A. 
Published: February 2007

AbstractChromosome analysis of three lymphoblast cell lines from New Guinea Burkitt lymphoma (QIMR‐GOR, QIMR‐AMB/1 and AMB/2), three lymphoblast cell lines from infectious mononucleosis (QIMR‐DAR, QIMR‐STE and QIMR‐GOE) and two lymphoblast cell lines from leukaemia (QIMR‐WIL and QIMR‐FIN) showed abnormalities associated with Group A, C, and G chromosomes. Each cell line contained diploid and near diploid cells. Some of the cell lines also contained pseudodiploid cells. Extra Group C or Group G chromosomes were found in a proportion of cells from some of the cell lines. Abnormal Group A chromosomes were also found. However, no one abnormality could confidently be assigned to a specific source of origin of the cell line studied.
Auto‐antibody to 7,12‐dimethylbenz(A)anthracene‐induced leukemic cells in rats as detected by immune adherence
Authors: Yoshida Takato O. , Imai Kuniyuki , Sugiyama Taketoshi 
Published: February 2007

AbstractSixteen Long‐Evans rats with leukemias induced by 7,12‐dimethylbenz(a)anthracene were studied for evidence of naturally occurring immunologic responses to their own leukemic cells with an immune adherence hemagglutination technique which was designed to detect fresh serum auto‐antibodies to the membrane of the leukemic cells. Auto‐antibodies to the cell membranes were found in 14 out of 16 rats, but were not demonstrable in the other two rats. Autochthonous thymus cells used as controls did not show positive immune adherence hemagglutination reactions with their own sera, nor did the leukemic cells show positive reactions with the pooled normal rat serum. These findings suggest a possibility that the leukemic rats are able to produce humoral antibodies against membrane‐specific antigens of autochthonous leukemic cells.
Carcinogenesis by avian sarcoma viruses. X. The decreased requirement for insulin‐replaceable activity in serum for cell multiplication
Authors: Temin Howard M. 
Published: February 2007

AbstractExperiments have been carried out to explain the decreased requirement for specific factor (s) in serum necessary for multiplication of chicken embryo fibroblasts infected and converted by avian sarcoma viruses. It has been shown that both uninfected and converted chicken cells in the G1 stage of the cell cycle are stimulated by one unit (molecule) of serum factor or insulin to continue through the cell cycle. In the absence of serum or insulin, uninfected cells continue to the next G1 stage and stop; converted cells continue through further divisions. Therefore, when the amount of serum is limiting for cell multiplication, the converted cells multiply more than uninfected cells.
Cytokinetics of the Krebs 2 carcinoma. I. Its effect on the cell population kinetics of duodenal crypt proliferation
Authors: Schmeer A. C. 
Published: February 2007

AbstractThe effect of the Krebs 2 transplantable solid carcinoma upon the cell cycle of the duodenal cryptal progenitor population has been determined by thymidine‐3H uptake and radioautography. A single pulse label of tritiated thymidine was injected into each of 183 CF1 mice with a 4‐day‐old solid tumor. The animals were then serially killed from 15 min to 24 hr later. Data were collected from a curve describing the rate of appearance and disappearance of labelled mitoses in the tumor and duodenum. An estimate of the time intervals of G1, S, M and G2 was calculated by two different methods and compared. The turnover rate of the cryptal progenitor population from the tumor‐bearing animals was found to be essentially similar to that of the control cryptal population of the non‐tumor‐bearing mice. The cytokinetics of the cell cycle of the Krebs 2 carcinoma is also reported. The methods described for collecting data on the turnover rate of tissues of both tumor‐bearing and non‐tumor‐bearing animals can be utilized to determine what effect growth‐promoting and growth‐inhibiting agents may have on the proliferation of normal progenitor compartments while at the same time measuring the effect of such drugs on the cytokinetics of an experimental tumor.
The influence of sex upon the development of friend virus leukaemia
Authors: Gillespie A. V. , Rowson K. E. K. 
Published: February 2007

AbstractThe morbidity and mortality in Parkes mice of both sexes following the injection of various doses of Friend leukaemia virus have been studied. Individual mice were tested for the presence of viraemia and for neutralizing and tumour‐specific cytotoxic antibodies. The principal findings were: (1) more rapid death among the female than the male mice; (2) the fact that, among the mice with splenomegaly, those with viraemia are usually male while those with neutralizing or cytotoxic antibodies are usually female; (3) the presence of circulating cytotoxic antibody in many mice with splenomegaly. It is hypothesized that female mice with Friend virus leukaemia are considerably superior to males in antibody‐producing capacity and that the former owe their more rapid death to tissue damage caused by an immunological response to the virus or cellular neo‐antigen.
The sensitivity of a yoshida sarcoma to methylene dimethane sulphonate
Authors: Fox Brian W. 
Published: February 2007

AbstractThe action of methylene dimethane sulphonate on the growth rate of the Yoshida sarcoma in rats is described. 1) The tumour, even when established for 12 to 14 days, is unusually sensitive to this alkylating agent and approximately 90% complete cures can be obtained. 2) About 10% of the treated tumours recur and, on retransplantation to new animals, show a marked resistance to the drug. The growth curves of the original and resistant lines, both unilaterally and bilaterally transplanted, following treatment by the drug, are described. 3) Animals in which the original tumour had completely regressed failed to accept a reimplantation of the original or of a resistant tumour.Comparable doses of myleran failed to produce complete regression of the tumour when administered 10 days after transplantation and the level of inhibition was much less than with methylene dimethane sulphonate. Cross‐resistance with triethylene melamine was observed.
Immunological studies on mouse mammary tumors. IV. Extraction and solubilization of transplantation antigen of mouse mammary tumor
Authors: Irie Reiko Furuse , Nishioka Kusuya , Tachibana Takehiko , Takeuchi Shoshichi 
Published: February 2007

AbstractAntigens present in mouse mammary tumor MM2 reacting with tumor‐specific antibodies were extracted with 0.2% deoxycholate. After the removal of deoxycholate by dialysis, most antigens were precipitated by centrifugation at 105,000 × g for 60 min. Hyperimmunization of C3H/He mice with these antigens induced heightened resistance against MM2. Antibodies appeared in the serum after a booster injection of deoxycholate extract of tumor cells was given. Antigens were solubilized from deoxycholate extract with distilled water. Purified soluble antigen inhibited the neutralization activity of the tumor‐specific antibody to MM2 tumor. From these observations, it is concluded that transplantation antigens of isografted mammary tumors in C3H/He mice are present in deoxycholate extracts of MM2 tumor.
Quantitative studies on the malignant transformation of mouse prostate cells by carcinogenic hydrocarbons in vitro
Authors: Chen T. T. , Heidelberger Charles 
Published: February 2007

AbstractA quantitative system for producing malignant transformation of adult C3H mouse ventral prostate cells in culture with carcinogenic hydrocarbons has been developed. Aneuploid cell lines derived from mouse prostate are plated at a low density on a feeder layer and treated with various hydrocarbons for different lengths of time; other dishes are treated with 0.5% dimethyl sulfoxide (the solvent for the hydrocarbons) as controls. After 8 days some dishes are fixed and stained and the colonies are counted for total plating efficiency. Two weeks later other dishes are also fixed and stained. In the DMSO controls, the cells remain as a monolayer. In the carcinogen‐treated dishes, piled‐up multilayered colonies are seen and their frequency is scored. It has been shown that each of such piled‐up colonies gives rise to fibrosarcomas in mice, whereas the cells obtained from the monolayer areas of treated dishes do not cause tumors. Thus, these piled‐up colonies represent malignant transformation, under conditions where no spontaneous malignant transformation occurs. There is an excellent quantitative correlation between the carcinogenic activities of eight hydrocarbons and the transformation frequencies they produce in this system. Malignant transformation has been produced by treatment with methylcholanthrene for only one day. The acquisition of heat sensitivity is an early consequence of malignant transformation in this system.
Decreased interferon sensitivity and production in cells transformed by sv40 and other oncogenic agents
Authors: Brailovsky C. A. , Berman L. D. , Chany C. H. 
Published: February 2007

AbstractFrom a pool of primary rat embryo fibroblast cells, three lines—two SV40‐infected and one control—were serially propagated. Prior to unequivocal morphological evidence of transformation, increased sensitivity to vesicular stomatitis virus (VSV) was found in the two SV40‐infected lines when compared to the control line. The increased VSV sensitivity of the transformed cells seems to be due to a diminished production of and sensitivity to interferon, and not to differences in adsorption. When a collection of diverse transformed cell lines were also compared with arbitrarily selected control cell populations, the majority of the transformed cells also exhibited enhanced VSV sensitivity. Lines transformed by methylcholanthrene also featured this property. The data suggest that diminished sensitivity to and production of interferon is an early consequence of infection by oncogenic viruses, and a property that persists in many lines of transformed cells.
Induction experiments with adenovirus and polyoma virus transformed cell lines
Authors: Burns William H. , Black Paul H. 
Published: February 2007

AbstractTechniques used successfully in inducing SV40‐transformed cells to produce infectious SV40 were employed in an attempt to induce cells transformed by other oncogenic DNA viruses, adenoviruses 2 and 12 and polyoma virus. These techniques included cocultivation and fusion of transformed cells with indicator cells, and mitomycin C treatment of these heterokaryons and of transformed cells. In addition, prior to induction experiments, some cell lines were passaged through animals or in the presence of BUdR in an effort to enhance their inducibility. All attempts to induce these transformed cells were unsuccessful. It is concluded from this study that the polyoma and adenovirus genomes, if present in their entirety in cells transformed with these viruses, are not as reactivable as is the SV40 genome in SV40‐transformed cells.
In vitro demonstration of tumor‐specific antigens in spontaneous mammary tumors of mice
Authors: Heppner G. H. , Pierce G. 
Published: February 2007

AbstractThe colony‐inhibition test has been used to demonstrate cellular immunity against spontaneous murine mammary tumors, both in autochthonous, mammary tumor virus (MTV)‐carrying BALB/cfC3H and in immunized, MTV‐free, BALB/c mice. Immunity could be demonstrated in nearly all cases against a mammary tumor with lymph‐node cells from mice which had experienced that tumor.One of eight tumors tested with lymph‐node cells from BALB/cfC3H mice which had spontaneously developed mammary tumors showed evidence of immunological cross‐reactivity, while seven of thirteen tumors did so when tested with immune cells from MTV‐free BALB/c mice. The data, therefore, indicate the presence of at least two types of tumor‐specific antigen (s) in mouse mammary tumors — a common one and an antigen specific for each neoplasm.