bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endocrine factors in the development of transplantable adrenal cortical tumors. I. Inhibition of the growth rate by corticotropin (ACTH)
Authors: Fiala Silvio , Fiala Anna E. 
Published: February 2007

AbstractThe growth rate of transplantable adrenocortical tumors in male LAF 1 mice was found to be inhibited in hypophysectomized and in adrenalectomized animals. Castration and sex hormones did not affect the growth of these tumors. In intact mice a striking inhibition of the growth rate of adrenocortical tumors was brought about by the administration of ACTH. Evidence was obtained that ACTH inhibited growth by a direct action on the tumor cells. When expressed in terms of units of DNA, the biochemical and cytochemical effects on adrenocortical tumor cells appeared qualitatively similar to the effects of this hormone on the normal adrenal cortex. A single injection of ACTH stimulated the activity of glucose‐6‐phosphate dehydrogenase. Repeated administration of ACTH produced an increased oxygen uptake by sliced tissue and a moderate accumulation of RNA in the microsomal fraction. Water extracts of acetone powdered, ACTH‐treated, adrenocortical tumors had lower dCMP‐deaminase activity than extracts from untreated tumors. When expressed in terms of units of DNA, the homogenates of ACTH‐treated adrenocortical tumors had a higher succinoxidase activity and the sliced tissue had a lower rate of anaerobic glycolysis than did corresponding samples of untreated adrenocortical tumors.
Transformation of newborn hamster cells with simian adenovirus SA7
Authors: Whitcutt J. M. , Gear J. H. S. 
Published: February 2007

AbstractNewborn Syrian hamster skin cells can be transformed in vitro by simian adenovirus SA7. The transformation occurs within 6–8 days of treatment with virus and the transformed cells give rise to tumour development when they are re‐inoculated into weanling hamsters.
Dose‐dependent recognition of irradiated isogeneic mouse lymphoma cells: Study by terminal dilution assay
Authors: Maruyama Yosh 
Published: February 2007

AbstractThe radiation response of an isologous mouse lymphoma was studied in detail by means of the TD50 method in irradiated and unirradiated recipients. The contribution of host resistance to radiosensitivity was shown to be similar to that determined earlier by the SD50 method, and produced significant alteration in survival curve shape. Assay by TD50 did not show significant differences when 0 R, or 100 R irradiated cells were assayed in pre‐ or non‐irradiated recipients. At 1,000 R or larger radiation doses, TD50 doses differed significantly. The recognizability of the irradiated cell increases with dose, suggesting that in addition to an alteration in cell growth and changes in numbers of killed cells, the absorbed irradiation may also have exposed the antigenic sites of surviving irradiated cells.
Immunologic studies on graffi‐virus‐infected spontaneous gross leukemia of akr mice
Authors: Micheel B. , Pasternak G. 
Published: February 2007

AbstractSpontaneous AKR Gross leukemias permanently produced Graffi virus if the cells had been repeatedly passaged in Graffi‐virus‐infected mice. Only one of 10 Graffi‐virus‐infected Gross leukemias investigated appeared to be immunologically indistinguishable from Graffi leukemias. Its cells contained the Graffi‐virus‐induced surface antigens as demonstrated by the phenomenon of tumor‐specific transplantation resistance in vivo and by immunofluorescence and absorption tests in vitro. The original leukemias transplanted independently did not contain these antigens.All other superinfected Gross leukemias were resistant to the rejection response of animals immunized against Graffi leukemia. Weak positive reactions in the immunofluorescence test indicated the presence of certain Graffi‐virus‐induced antigens at their cell surface. In addition, the cells absorbed virus‐neutralizing antibodies from Graffi‐immune sera. Absorbed sera still contained antibodies against surface antigens of Graffi target cells. It is suggested that Graffi leukemia cells as well as one of the Graffi‐virus‐infected Gross leukemias tested contain viral and virus‐induced new cellular antigens while the other infected Gross leukemias contain only viral antigens.
The differential action of neonatal thymectomy in mice infected with murine sarcoma virus‐harvey (msv‐h)
Authors: East June , Harvey Jennifer J. 
Published: February 2007

AbstractIntact C3H/Bi and BALB/c mice infected with Murine Sarcoma Virus‐Harvey (MSV‐H) at 3–16 days developed either „early”︁ erythroblastic splenomegaly with concomitant severe anaemia and sarcomas at sites related to the route of inoculation or, after a perceptible delay, „late”︁ lymphocytic leukaemia. These effects were dependent on the dilution of the virus and the age of the recipients. Neonatal thymectomy both accelerated the erythroblastosis and increased the tumour incidence in older 14–16 day recipients but prevented (or indefinitely postponed) the lymphocytic leukaemia. This differential action of neonatal thymectomy is discussed in the light of current immunological theory. A virus causing only lymphocytic leukaemia was separated by passage from the plasma of leukaemic intact or non‐leukaemic thymectomized mice. Thus, in these experiments, MSV‐H behaved as a complex of two viruses, one causing the early changes and a second, always present in higher concentration but slower acting, responsible for the late changes.
Relationships of chromosomal and pathological findings in rous sarcoma virus‐induced tumours in the mouse
Authors: Mark J. 
Published: February 2007

AbstractSarcomas were induced in CBA mice by RSV‐SR inoculated in the neonatal period. The latent period ranged from 21 days up to more than 2 years; the peak incidence occurred around 4–5 months. The tumour incidence was about 45% after 6 months and nearly double after two years of observation. Multiple tumours, usually with closely similar latent periods, were frequent. Among the sarcomas studied chromosomally, small size, slow growth and a high degree of histological maturity were interconnected factors correlated with the occurrence of a normal diploid stemline. Opposite characteristics were typical of the sarcomas with a numerically and structurally changed stemline, especially the tetraploid group.Metastases were found only in the lungs and they occurred in approximately one‐third of the cases. No cysts were observed in the lymph nodes but a few instances are on record with cysts in the spleen and in the neighbourhood of the pancreas, as well as in connection with the sarcomas. A large amount of acid mucopolysaccharides could be found in all tumours studied in this respect.By back‐transfer to chickens, Rous sarcomas were elicited by roughly 75% of the mouse sarcomas investigated. Nearly all the negative mouse tumours had a latent period of more than one year.
Tumor fluid thromboplastin activity
Authors: Frank Arthur L. , DouglasHolyoke E. 
Published: February 2007

AbstractThe thromboplastin activity of T‐241 Lewis sarcoma peripheral fluid and control subcutaneous fluid in C57BL/6Ja male mice was measured, using a calcium reconstitution assay. The material was collected in Millipore filter chambers.At low dilutions of the collected material there was a statistically significant increase in clotting activity of the tumor peripheral fluid. The calcium ion concentration of the collected fluid was also measured. It was also noted that gels were found more frequently, and in larger amounts, in the chambers in tumor‐bearing animals than in the controls.
Anchorage and growth regulation in normal and virus‐transformed cells
Authors: Stoker Michael , O'Neill Charles , Berryman Susan , Waxman Vivienne 
Published: February 2007

AbstractMany cell types will grow when attached to a rigid surface but not in suspension, a phenomenon termed „anchorage dependence”︁. Anchorage dependence can be studied by incorporating solid particles of varying size into gels. It has been found that colonies will form on glass fibrils 500 μ in length, but not in the presence of silica fragments smaller than the cells. This shows that the suspending medium is not itself inhibitory, and confirms the requirement for a rigid surface of adequate size.The state of inhibited cells in suspension culture was examined by dispersing them in a methyl cellulose gel, in vessels lined with agar. In this system aggregation is prevented and the cells may be recovered quantitatively. Normal, as well as transformed, cells increase in size, and a proportion synthetize DNA during the first 24 hours in suspension culture. Growth and DNA synthesis in normal cells then virtually cease, while transformed cells continue to grow into colonies. The stationary normal cells remain competent for further growth for at least a week in suspension. When such cells are allowed to attach to a rigid surface in the presence of colchicine, DNA synthesis occurs and is followed by mitosis. These results indicate that suspended cells are blocked between mitosis and the end of the S phase of the cycle.
Accumulation of labelled vitamin B12 in some transplanted tumours
Authors: Flodh Hans , Ullberg Sven 
Published: February 2007

AbstractThe accumulation of labelled vitamin B12 in four different kinds of transplanted tumour was studied using whole‐body autoradiography and impulse counting. The tumours were 90Sr‐induced soft fibroblastic osteosarcomas, spontaneous mammary carcinomas, Ehrlich ascites and Moloney virus‐induced tumours. The 90Sr‐induced soft sarcoma, which was the most rapidly growing tumour, showed the greatest uptake of radio‐B12, the concentration being higher than in any normal tissue. In all tumours the radioactivity was localized to the peripheral, still actively growing parts. It is suggested that a connection exists between growth rate and accumulation of B12 and that B12 is needed for rapid cell multiplication.
Morphology of tumors induced in Hamsters by Simian adenoviruses
Authors: Levenbook I. S. , Chigirinsky A. E. , Tsetlin E. M. , Dodonova N. N. , Altstein A. D. 
Published: February 2007

AbstractSubcutaneous hamster tumors induced by Simian adenovirus SA7, strains C8, B105 and C626, were found to be poorly differentiated sarcomas having morphological features which distinguish them from tumors induced at the same site by papovaviruses and the Rous sarcoma virus. In general, the adenovirus‐induced tumors were morphologically alike, C8‐induced sarcomas showing some differences. Tumors induced by this strain in the subcutaneous tissue, muscles, peritoneum and mediastinum were morphologically identical. Tumors found in the brain were mainly malignant ependymomas and choroid plexus carcinomas, generally originating in neuroectoderm.The oncogenicity of adenovirus SA7 (C8) in meso‐ and ectodermal cells has thus been demonstrated.
Rǒle de l'Immunité dans le Rejet des Tumeurs Induites par le Virus MSV. Effet des Sérums Antithymocytes
Authors: Varet B. , Lévy J. P. , Leclerc J. C. , Senik A. 
Published: February 2007

The rǒle of immunity in the rejection of tumours induced by the MSV virus. The effect of antithymocyte serumsRabbit anti mouse lymphoïd cell serum (ALS) facilitated the outgrowth of virus‐induced Rhabdomyosarcoma (MSV) in adult BALB/c and C57Bl/6 mice.Whereas all tumors induced in control mice completely regressed, most of the tumors induced in ALS inoculated mice grew progressively and killed the host. Frequency of positive mice was also greatly increased. Lymphocytes of mice immunized against MSV were able to inhibit the outgrowth of transplanted Moloney lymphoma cells. These experiments showed that spontaneous rejection of MSV induced tumors in adult mice is an immunological phenomenon mediated by immune lymphoïd cells.The rǒle of cellular immunity and antibody in tumor rejection are briefly discussed.
Further electron microscopic studies on the mechanism of carcinogenesis: The specificity of the changes in carcinogen‐treated mouse skin
Authors: Tarin D. 
Published: February 2007

AbstractThis work was undertaken to determine if the ultrastructural changes seen in mouse skin carcinogenesis (Tarin, 1967a) are specific to the carcinogenic process.Electron microscopic examination of skin treated with non‐carcinogenic irritant chemicals (benzene, turpentine) showed that the dermo‐epidermal junction remained intact. The changes seen in this region in methylcholanthrene‐treated skin were not present.The irritants did, however, produce changes in the epidermis and dermis but these differed from those seen in carcinogen‐treated skin. The epidermis underwent regular hyperplasia and there was an increase in the number of inflammatory cells in the dermis. Dermal collagen fibre structure and arrangement were not altered.It is concluded that the changes seen at the dermo‐epidermal junction in carcinogen‐treated skin are directly related to the carcinogenic process and are not the result of non‐specific irritation.The nature of the carcinogenic process is considered and disturbance of interaction between epithelium and connective tissue is offered as an explanation for the behaviour of neoplastic tissue. This hypothesis is discussed in the context of modern work which has shown that such interactions are of importance in the development and maintenance of normal tissue architecture.
Effect of herpes simplex virus on human embryonic cells latently infected with reovirus type 3
Authors: Bell Thomas M. , Munube Germano M. R. , Griffin E. R. 
Published: February 2007

AbstractA persistent latent infection of human embryo fibroblasts by reovirus type 3 was found to be due to the continuous infection of a small proportion of the cells. Super‐infection of these cultures by herpes simplex virus resulted in the destruction of the monolayers by the herpes virus without any obvious signs of interference.Electron microscopic examination of these doubly infected cultures showed the presence of multi‐nuclear blebs and an unusual, “condensed‐mass”, form of intranuclear herpes virus. The implications of these findings are discussed.
The stimulating effect of complete Freund's adjuvant on tumour induction by polyoma virus in mice and By Rous sarcoma virus in rats
Authors: Ter‐Grigorov V. S. , Irlin I. S. 
Published: February 2007

AbstractComplete Freund's adjuvant was shown to greatly stimulate viral oncogenesis both in the case of polyoma virus in mice and in the case of Rous sarcoma virus in rats. Tumours appeared in 74% of CC57BR/Mv mice infected when newborn with polyoma virus — adjuvant emulsion, whereas control mice injected with virus alone failed to develop tumours. Rous virus (Carr‐Zilber strain) and adjuvant when administered together as emulsions to Wistar rats (newborn or sucklings as well as 2.5‐month‐old animals) resulted in a 100% tumour incidence. In control animals treated with the virus alone when 0–4 days old, tumour incidence was no more than 30–40%; no tumours appeared in control animals which received virus alone when they were more than 2 weeks old. A significant stimulating effect of Freund's adjuvant was also revealed when the virus was inoculated into 4‐ to 15‐day‐old rats which received adjuvants as neonates. Thirty per cent of rats given virus — adjuvant emulsion produced measurable quantities of complement‐fixing antibodies to soluble antigens of Rous sarcoma, while in animals given virus alone such antibodies were not demonstrable. It is suggested that the stimulating action of complete Freund's adjuvant on polyoma and Rous oncogenesis is based upon a mechanism similar to the classical “enhancement phenomenon”.
Lymph‐node metastases after intratibial transplantation of tumors
Authors: Franchi G. , Innocenti I. Reyers‐Degli , Rosso R. , Garattini S. 
Published: February 2007

AbstractEhrlich carcinoma and Sarcoma 180 implanted in the marrow cavity of the tibia induced the formation of visible metastases in distal lymph nodes to a larger extent than when they were implanted in the leg muscles. Differences in survival time or in tumor growth did not explain this difference in metastasis formation. Immediately after transplantation, cancer cells were seen in the blood of animals implanted intratibially but not of those implanted intramuscularly. However, this effect per se was not important because amputation of the leg after the end of the early dissemination completely prevented the development of metastases.
Positively charged groups at cell surfaces
Authors: Weiss L. , Bello J. , Cudney Toni L. 
Published: February 2007

AbstractAn attempt was made to identify positively charged amino‐groups at the electrokinetic surfaces of human and mouse erythrocytes, cultured cells derived from a human osteogenic sarcoma, and murine ascites sarcoma 37 cells. Following reactions of these cells with formaldehyde, 2,4,6‐trinitrobenzenesulfonic acid; 2‐chloro‐3,5‐dinitropyridine or 2‐chloro‐3,5‐dinitrobenzoic acid, no consistent change in their electrophoretic mobilities was observed. If a number of positively charged groups commonly associated with proteins had been present at the cellular electrokinetic surface, their reaction with the various reagents would have resulted in an increase in net surface negativity. We therefore conclude that these groups are not present at the surfaces of the cells studied.
Histologic types of gastric carcinoma in high‐ and low‐risk areas
Authors: Muñoz Nubia , Correa Pelayo , Cuello Carlos , Duque Edgar 
Published: February 2007

AbstractA total of 322 cases of gastric cancer from the surgical material of the Pathology departments of three cities in Colombia and of Mexico City were divided according to the histologic classification of Laurén into two main histologic types: intestinal and diffuse. The intestinal type was predominant in high‐risk areas for stomach cancer, while the diffuse type was more frequent in the low‐risk areas. Data presented suggest that these two main histologic types may be connected with different precancerous lesions as a significant proportion of the intestinal type carcinomas arose from intestinal metaplasia of the gastric mucosa, while the diffuse type showed no such origin. The significance of these findings in relation to the genesis of stomach cancer is discussed.
Transformation of foetal human leukocytes in vitro by filtrates of a human leukaemic cell line containing herpes‐like virus
Authors: Pope J. H. , Horne M. K. , Scott W. 
Published: February 2007

AbstractTransformation of foetal human leukocytes followed inoculation with a filtrate of cells of the QIMR‐WIL human leukocyte cell line, previously shown to carry a herpes‐like virus. Proliferation of leukocytes was generally noted 24–35 days after inoculation, and resulted in the establishment of cell lines resembling those derived from peripheral leukocytes of patients with leukaemia or infectious mononucleosis. The sex of representative transformed lines confirmed that they were of foetal origin. Transformation occurred with two separate filtrates of QIMR‐WIL cells, with leukocytes from five individual foetuses, and with leukocytes from bone marrow, thymus and spleen. Various control inocula gave negative results, including culture medium and filtrates of Raji and QIMR‐GOR cell lines. Representative transformed lines were found to fix complement with human serum known to react with QIMR‐WIL and QIMR‐GOR cells; but similar serum showed little evidence of reaction by immunofluorescence. The transformed cell lines studied appeared to be essentially diploid, and subterminal constrictions involving Group C chromosomes were noted in a small proportion of cells in 8/9 lines. In preliminary studies, the transforming factor was found to be sensitive to heat and ether, was sedimented at 70,000 × g and retained by a filter of APD 50 mμ; these results are compatible with the herpes‐like virus of the QIMR‐WIL cells being the transforming factor.
The properties of sarcomas induced in wistar rats by rous sarcoma virus (schmidt‐ruppin)
Authors: Harris R. J. C. , Chesterman F. C. , McClelland Rosalind M. 
Published: February 2007

AbstractThe properties of single cell clones derived from sarcomas induced in young Wistar rats by RSV (S‐R) are compared. Most sarcomas do not produce infectious RSV but are virogenic (i.e. capable of inducing Rous tumours) for chicks. One sarcoma was not virogenic. Clones were tested for virus release either alone in vitro or after passage on the chorioallantoic membrane of the embryonated egg. The avian sarcoma‐leukosis group‐specific (complement‐fixing) antigen could not be detected in either virogenic or non‐virogenic cells. A few primary Rous rat sarcomas showed the presence of virus‐induced transplantation antigen but this could not be detected by graft‐rejection in serially‐passed tumours, or in any of the clones.The virogenic clones were more malignant for rats than the non‐virogenic ones, but this property was not associated with the presence or absence of virus‐specific antigens.
Oocyte destruction and ovarian tumorigenesis after direct application of a chemical carcinogen (9:10‐dimethyl‐1:2‐benzanthrene) to the mouse ovary
Authors: Krarup Torben 
Published: February 2007

AbstractOvaries of immature mice were painted with 9:10‐dimethyl‐1:2‐benzanthracene (DMBA), and the effect of the carcinogen on the number of oocytes as well as on the subsequent development of ovarian tumours was studied.DMBA had an immediate effect on the small oocytes. Their number was rapidly reduced within the first 4 weeks after treatment, followed by a more gradual elimination, comparable to the elimination rate in the control ovaries. The growing and large oocytes were not primarily affected by the carcinogen; however, after the first 4 weeks post treatment their number was also decreased. This was considered to be secondary to the reduction in the number of small oocytes. No more oocytes remained in the ovaries of 6‐ to 9‐month‐old treated animals, an age at which considerable numbers were still present in the ovaries of control mice.Simultaneously with the elimination of oocytes there occurred a pathological development in the ovaries. There seemed to be a positive correlation between the rate of oocyte disappearance and the pathological development: the faster the oocytes disappeared the earlier the abnormal development began. This ultimately led to ovarian tumours, only seen in ovaries totally depleted of oocytes.It is concluded that DMBA applied to the ovaries acts directly on the small oocytes and destroys many of them. The neoplastic development is considered secondary to the reduction of the oocyte population and is apparently not caused by the carcinogen itself. This is supported by the fact that the development of ovarian tumours in mice is always preceded by a rapid disappearance of oocytes, regardless of whether the method of tumour induction in X‐irradiation, intrasplenic transplantation of an ovary after gonadectomy, treatment with a chemical carcinogen, or genetic deletion of oocytes.
Continuous production of avian sarcoma virus B77 by rat tumour cells in tissue culture
Authors: Šimkovič D. , Popovič M. , Švec J. , Grófová M. , Valentová N. 
Published: February 2007

AbstractThe rat tumour RBI, previously induced by injection of fowl sarcoma B77 tissue into newborn rats, was adapted to long‐term growth in tissue culture. Two cell lines, 16B177 and 17B177, were derived from the tumour. Both cell lines were capable of continuous production and release of infectious B77 virus over a period of more than two years' in vitro cultivation. The virus present in cell‐free tissue culture media induced characteristic sarcomas upon inoculation into young chicks.Preliminary chromosomal analysis of the uncloned population of 17BI77 cells confirmed their rat origin and revealed that the hypotriploid stem‐line predominates, being represented by 59 chromosomes.