bluuebunny/crossref_metadata_2025_split huggingface dataset:
The lymphocyte response to primary moloney sarcoma virus tumors: Definition of a non‐specific component of the in vitro cellular hyporeactivity of tumor‐bearing hosts
Authors: Kiessling Rolf , Bataillon Georges , Lamon E. W. , Klein Eva 
Published: February 2007

AbstractAdult CBA mice injected with Moloney Sarcoma Virus (MSV) developed tumors within 5 to 8 days which usually completely regressed within 1 month. Maximal tumor size was variable, occurring between 10 and 15 days. Lymphocytes from these animals were examined for activity against syngeneic target cells bearing the Moloney Leukemia Virus (MLV) ‐associate dcell‐surface antigen. As previously found with BALB/c mice, the lymphocytes were found to be active in microcytotoxicity tests against these target cells; however, the animals which were bearing tumors at the time of testing were found to have the least active lymphocytes. These animals were also immunized against H‐2d antigens 10 to 13 days prior to testing and their lymphocytes tested for cytotoxicity against H‐2d target cells in 51Cr release assays. It was found that the tumor‐bearing animals, by day 10‐16 after MSV infection, had lymphocytes which were significantly less active against the H‐2d antigens than those of animals tested prior to the development of tumor or those in which the tumors had regressed. It was thus concluded that a component of the cellular hyporeactivity, as measured by in vitro cytotoxicity in these primary MSV tumor bearing hosts, is non‐specific.
Treatment of Kaposi's sarcoma by combination of actinomycin‐D, vincristine and imidazole carboxamide (NSC‐45388): Results of a randomized clinical trial
Authors: Olweny Charles L. M. , Toya Tom , Katongole‐Mbidde Edward , Lwanga Stephen K. , Owor Raphael , Kyalwazi Sebastian , Vogel Charles L. 
Published: February 2007

AbstractPrevious trials at our Institute revealed the effectiveness of actinomycin‐D and vincristine in the treatment of Kaposi's Sarcoma. We herein report the results of a further randomized trial designed to test the efficacy of the three‐drug combination consisting of actinomycin‐D, vincristine and imidazole carboxamide and to compare the results with those obtained by combining actinomycin‐D and vincristine only for all forms of Kaposi's Sarcoma. Of the 40 patients treated with two drugs, 22 (55%) achieved complete tumour regression, 13 (32.5%) had partial response and 5 (12.5%) did not respond. On the other hand, 30 out of 32(94%) of those receiving three drugs had complete tumour regression, one had partial and one had no response. There is a significantly higher complete response rate (p<0.002) in the group receiving three drugs than in that receiving two drugs. The side effects encountered were comparable.
Absence of RSV production in enucleated RSV‐transformed virogenic mammalian cells fused with chick embryo fibroblasts
Authors: Donner L. , Turek L. , Svoboda J. 
Published: February 2007

AbstractCells of an RSV‐transformed virogenic Chinese hamster line, RSCH, were enucleated by combining the actions of high g forces and cytochalasin B, and fused with RIF‐free chick embryo fibroblasts using beta‐propiolactone‐inactivated Sendai virus. Contrary to nucleate RSCH cells, enucleated RSCH cells did not produce RSV after fusion. This finding supports the view that proviral RSV DNA is not fully transcribed in a virogenic cell.
Rejection of tumors and metastases in fischer 344 rats following intratumor administration of killed corynebacterium parvum
Authors: Likhite Vilas V. 
Published: February 2007

AbstractKilled Corynebacterium parvum vaccine was infiltrated into growing subcutaneous tumors (two antigenically different types) syngeneic to the Fischer 344 rats. In all these animals decrease in tumor size was followed by total and lasting disappearance. The protective response conferred as a result of intratumor C. parvum appeared to prevent progressive growth of potentially lethal pulmonary and visceral metastases. Animals which rejected their tumors showed an increased protection that was tumorspecific. Histological examination of tumors from rats exhibiting C. parvum‐mediated rejection revealed an intense non‐specific infiltration consisting mainly of macrophages with some lymphocytes. Of the groups of rats treated with surgical removal of the growing tumor, 30‐60% died with growing tumors and metastases. Suppressed rates of tumor growth and prolonged survival were observed in the group of rats treated with killed C. parvum subcutaneously 1 cm around and away from the growing tumors.
Influence of exogenous interferon on the peripheral white blood cell count in mice
Authors: Degré Miklos 
Published: February 2007

AbstractThe effect of interferon (IF) injected intraperitoneally on the peripheral white blood‐cell (WBC) count in mice was studied. Mouse serum or brain IF produced in vivo in different mouse strains by injecting various viral inducers depressed the lymphocyte count from 3 to 24 h after the injection. The effect was correlated to the antiviral titer of the preparations. The inhibitory factor exhibited physico‐chemical properties of IF. Crude IF preparations obtained from mouse cell cultures, human IF and mock preparations devoid of anti‐viral activity exerted no lymphocytopenic effect.
Cytogenetic studies on human lymphoblastoid cell lines from burkitt's lymphomas and other sources
Authors: Jarvis J. E. , Ball G. , Rickinson A. B. , Epstein M. A. 
Published: February 2007

AbstractThe occurrence and incidence of a characteristic banding abnormality in a No. 14 chromosome has been studied in Burkitt‐lymphoma‐derived and certain other EB virus‐associated lymphoblastoid cell lines. The abnormality was readily detected in 7 out of 7 Burkitt lines, and when present could be seen in 100% of cells with recognizable No. 14 chromosomes. In contrast, the abnormality was not observed in 775 cells from 31 infectious mononucleosis‐derived lines nor in 450 cells from 18 lines obtained from cord blood lymphocytes experimentally transformed by EB virus in vitro. The significance of the abnormality as an indication of cells transformed by the virus in vivo is discussed, and the importance of this considered in relation to a possible oncogenic role for EB virus in man.
Isolation of a primate type‐C virus from a lymphomatous baboon
Authors: Goldberg Robert J. , Scolnick Edward M. , Parks Wade P. , Yakovleva L. A. , Lapin B. A. 
Published: February 2007

AbstractA type‐C RNA virus has been isolated from various tissues of a lymphomatous baboon (sp. P. hamadryas). Virus isolations were made by co‐cultivating baboon cells from the inguinal and mesenteric lymph nodes, testes, kidneys and spleen with cells of canine or human origin. The isolated virus grew in canine, bat, rhesus and human cells but not in cells of mouse, rat, cat or rabbit origin. The baboon isolate resembled a type‐C virus when infected cells were examined by thin section in the electron microscope. In addition, the virus was capable of providing helper function by rescuing and transmitting the Moloney and Kirsten sarcoma virus genome from non‐productively transformed cells. Antibody directed against the RD114 virus reverse transcriptase was very effective in inhibiting the baboon virus polymerase while anti‐mouse and woolly type‐C virus polymerase antibodies had no significant inhibitory activity. Further analysis by immunodiffusion and competitive radioimmune assay revealed a close immunological relationship between this virus, RD114 and another type‐C virus isolated from the placenta of a different species of baboon. Finally, three different classes of interspecies antigenic determinants have been demonstrated in mammalian type‐C viruses.
Evaluation of epstein‐barr virus‐associated nuclear antigen with various human cell lines
Authors: Suzuki Masahiro , Hinuma Yorio 
Published: February 2007

AbstractCritical evaluation of the anti‐complement immunofluorescence (ACIF) test for Epstein‐Barr virus‐associated nuclear antigen (EBNA) in known EBV‐associated cell lines was carried out. The ACIF procedure, in which the cell smears were thoroughly air‐dried and fixed with carbon tetrachloride (for 15 min at room temperature), provided reproducible staining results with minimum variations. The fixed smears could be stored for at least 5 weeks at −8° C without loss of reactivity. On the basis of the above evaluation, a total of 59 human cell lines, which had unknown or uncertain association with EBV, were examined for the presence or absence of EBNA by the ACIF procedure. All of the cell lines tested could be judged positive or negative for EBNA. All of 21 lines growing as monolayer or in a mixed state of monolayer and suspension, were negative. Of 38 lines grown in suspension, 36 lymphoblastoid lines were positive but the remaining 2 lines (seemingly not lymphoblastoid) were negative.
Actinomycin‐D‐resistant in vitro mouse cell line derived from a methylcholanthrene‐induced sarcoma: Decrease of malignancy and antigenic characteristics
Authors: Belehradek J. , Biedler J. L. , Thonier M. , Barski G. 
Published: February 2007

AbstractThe tumorigenic EPO clonal cell line, derived from a methylcholanthrene‐induced murine sarcoma, was exposed to increasing concentrations of actinomycin D and gave rise to a subline, resistant to 0.02 μg of actinomycin D per ml of medium, which was designated EPO/ADj. Drug resistance was accompanied by a striking decrease of tumorigenic capacity as determined by the tumor take incidence and tumor growth rate in syngeneic C57BL/6 mice (normal and X‐irradiated), as well as by tumor take incidence in the cheek pouch of cortisone‐treated weanling Syrian hamsters. One of the tumors obtained after inoculation of EPO/ADj cells into syngeneic mice was reexplanted in culture and developed as the EPO/ADj/T subline. It was found to be relatively resistant to actinomycin D as compared to the parental EPO cells. The morphology of cells changed with actinomycin‐D‐resistance: EPO/ADj cells were more spread and flattened and less overlapping than the original fibroblast‐like EPO cells. EPO/ADj/T cells, however, had an aspect similar to that of EPO cells. No major differences were seen between the karyotypes of EPO, EPO/ADj and EPO/ADj/T cells. Tumor‐specific antigen(s), characteristic of the drug‐sensitive, parental EPO line, was expressed in the resistant EPO/ADj and EPO/ADj/T lines, as shown by: (a) transplantation resistance to challenge with EPO cells in syngeneic mice pretreated with EPO/ADj cells; and (b) cross‐reactivity in indirect immunofluorescence tests performed with sera from syngeneic animals hyperimmunized with EPO or EPO/ADj cells. Furthermore, an additional surface antigen (s), absent from EPO cells, was demonstrated in EPO/ADj and EPO/ADj/T cells by means of immunofluorescence tests performed with specific anti‐EPO/ADj syngeneic sera previously absorbed on EPO or EPO/ADj cells.
Genetic control of the regulation of cell susceptibility to carcinogenic polycyclic hydrocarbons by cyclic AMP
Authors: Huberman Eliezer , Yamasaki Hiroshi , Sachs Leo 
Published: February 2007

AbstractThe metabolism of benzo (a) pyrene (BP) in normal golden hamster and BHK cells in culture was increased by treating the cells with dibutyryl cyclic AMP (dcAMP), prostaglandin E1, theohylline or aminophylline. The largest increase, 6‐fold for the normal cells and 20‐fold for the BHK cells, was obtained by treatment with both dcAMP and aminophylline. Treatment with aminophylline also stimulated the metabolism of 20‐methylcholanthrene and 7,12‐dimethylbenz (a) anthracene. The increased metabolism of these three carcinogenic polycyclic hydrocarbons was associated with an increased cytotoxicity. Treatment with aminophylline increased the cytotoxicity of five other potent and weak carcinogenic polycyclic hydrocarbons, but not of two non‐carcinogenic polycyclic hydrocarbons. The amount of BP metabolism in 27 different cell types from various mammals, including humans, ranged from less than 0.1 μg to 2.3 μg metabolized BP per 106 cells. Treatment of these different cell types with aminophylline gave either an increase in BP metabolism, an induction of metabolism in cells that did not metabolize without aminophylline, or no induction after treatment with aminophylline and dcAMP. The existence of responding and non‐responding cell lines indicates that the regulation of the level of polycyclic hydrocarbon metabolism by dcAMP is genetically controlled. The induction of metabolism in cells that did not metabolize without aminophylline resulted in the conversion of cell resistance to cell susceptibility to the cytotoxic effect of BP. Treatment with dcAMP and aminophylline can therefore be used to increase the sensitivity of screening tests for chemical carcinogens.
Properties of reticulum‐cell sarcomas in SJL/J mice. I. Proliferative response to tumor cells of T‐derived lymphoid cells from normal mice
Authors: Lerman Stephen P. , Chapman Judith M. , Carswell Elizabeth A. , Thorbecke G. Jeanette 
Published: February 2007

AbstractCells from reticulum‐cell sarcomas (RCS), tumors with a probable B‐cell origin in the SJL/J mouse strain, induced a high degree of proliferation in 6‐bearing syngeneic lymph‐node and thymus cells obtained from young non‐tumorous mice. Although of considerably lower magnitude, a proliferation of SJL/J thymus cells to syngeneic normal lymph‐node cells was also noted. Sera from normal syngeneic mice did not block either of these proliferative responses. Stimulation by RCS cells also occurred with normal lymph‐node cells from F1 hybrids, SJL/J × C57Bl/6, and SJL/J × ASW and from the H‐2S identical ASW mouse strain. It is suggested that these results are due either to the presence of viral antigens on the surface of RCS cells or to an exaggerated form of the normal syngeneic response of T to B lymphocytes. Another tumor of B‐cell origin, the PU5 tumor of BALB/c mice, failed to induce proliferation in normal syngeneic lymph‐node or thymus cells.
Activity of uridine kinase in different lines of AKR leukemic mice and its relation to chemotherapy with 5‐azacytidine
Authors: Veselý J. 
Published: February 2007

AbstractThe sensitivity of different wild‐type and 5‐azacytidine‐resistant lines of AKR leukemic mice to 5‐azacytidine varies in relation to the activity of uridine kinase isolated from corresponding leukemic livers. The enhancement of liver uridine kinase activity observed in leukemic mice following the administration of a single large dose of 5‐azacytidine is accounted for by the presence of hepatocytes in infiltrated leukemic livers. The optimal schedule for the treatment of AKR leukemic mice with 5‐azacytidine requires equally divided doses administered daily and not an initial high dose followed by low doses.
Non‐producer human cells induced by murine sarcoma virus
Authors: Rhim John S. , Cho Han Y. , Huebner Robert J. 
Published: February 2007

AbstractNon‐producer (NP) human cells were isolated from transformed foci induced by the Kirsten mouse sarcoma virus. These morphologically altered NP cells produced neither infectious virus nor complement‐fixing antigens of the murine sarcoma‐leukemia virus complex. However, the sarcoma virus genome could be rescued from these NF cells by co‐cultivation with cells carrying „helper”︁ Kirsten mouse leukemia virus or Woolly Monkey leukemia virus. The possible usefulness of these cells in efforts designed to detect covert or repressed RNA tumor viruses in various animal and human tissues is discussed.
Epstein‐barr virus‐induced transformation of human leukocytes after cell fractionation
Authors: Schneider Ulrich , Hausen Harald Zur 
Published: February 2007

AbstractThe efficiency of transformation of human lymphocytes after infection with Epstein‐Barr virus (EBV) was determined in fractionated and non‐fractionated preparations derived from 16 human cord blood samples and two blood samples from adult donors. The transformation efficiency of macrophage‐depleted leukocytes was consistently lower as compared to non‐fractionated leukocytes. Additional depletion of B‐cells resulted in a further decrease. Reduction of T‐cells, however, did not influence significantly the transformation rate. In non‐fractionated leukocyte cultures, as well as in macrophage‐depleted and B‐cell enriched cultures, colonies of transformed cells were regularly observed within the first week of cultivation. All cell lines established after EBV‐infection revealed membrane‐bound immunoglobulin. Reconstitution of macrophage‐depleted, B‐cell enriched or B‐cell depleted cultures with autologous macrophages resulted in an increase of the transformation efficiency up to the values of non‐fractionated leukocyte preparations. Addition of heterologous human embryonic lung fibroblasts resulted in a similar increase. The results support the interpretation that EBV transforms only those cells of the hematopoetic system which are derived from the bone‐marrow entity. The transformation efficiency is considerably increased by co‐cultivation of lymphocytes with macrophages and heterologous human fibroblasts which seem to exert a feeder‐layer effect by enhancing survival of lymphocytes in vitro.
Type‐c virus‐specific nucleic acid sequences in cultured rat cells
Authors: Tsuchida Nobuo , Gilden Raymond V. , Hatanaka Masakazu , Freeman Aaron E. , Huebner Robert J. 
Published: February 2007

AbstractSingle‐stranded DNA transcripts of rat type‐C viruses prepared in the presence of actinomycin D, hybridized specifically to DNA of several rat cell cultures with no obvious qualitative or quantitative differences. Similar products prepared from a pseudo‐type sarcoma virus with contributions from rat and mouse type‐C viruses hybridized to both rat and mouse cellular DNA, while mouse viral transcripts did not hybridize to rat cell DNA. Viral RNA was detected in all rat cells by means of the rat viral DNA transcripts, with some differences between untreated low‐passage cells and sister cultures treated with bromodeoxyuridine or bromodeoxyuridine and methylchol‐anthrene. Cells treated with both compounds were previously shown to be transformed and tumorigenic, and these were distinguishable by kinetic analysis from the control cells.
In vitro immunological studies on east african cancer patients. II. Increased sensitivity of blood lymphocytes from untreated burkitt lymphoma patients to inhibition of spontaneous rosette formation
Authors: Gross R. L. , Levin A. G. , Steel C. M. , Singh S. , Brubaker G. , Peers F. G. 
Published: February 2007

AbstractFrozen aliquots of peripheral blood mononuclear cells from patients with Burkitt's lymphoma (BL) at various stages of the disease have been compared with samples from East African children who were healthy or who suffered from non‐malignant disorders. Using the sheep‐cell rosette test (which is believed to identify T‐lymphocytes), we found a significant reduction in the proportion of rosette‐forming cells (RFC) in the samples from untreated BL patients. After induction of remission the difference between BL patients and controls was abolished. Rosette formation was more readily inhibited by anti‐lymphocyte globulin (ALG) in samples from untreated BL patients than in controls. On induction of remission the rosette inhibition curve shifted towards the control values. The findings are compatible with the presence, in untreated BL, of a circulating factor which impairs the capacity of T‐lymphocytes to form rosettes with sheep erythrocytes. It remains to be established whether the functional capacity of T‐cells to protect the host against tumour proliferation is also impaired.
In vitro immunological studies on east african cancer patients. III. Spontaneous rosette formation by cells from burkitt lymphoma biopsies
Authors: Gross R. L. , Steel C. M. , Levin A. G. , Singh S. , Brubaker G. 
Published: February 2007

AbstractSpontaneous rosette formation was observed in eight out of nine Burkitt lymphoma biopsies. These were examined fresh and/or after culture in vitro for up to 48 h. The percentage of rosettes varied from 3.7% to 38%. There was a tendency for the percentage of rosettes to increase with time in tissue culture. It is suggested that the rosette‐forming cells are T‐lymphocytes infiltrating the tumour and functioning as a host defence mechanism against the proliferating tumour cells.
Transformation of horse skin cells by type‐c sarcoma viruses
Authors: Rhim Johng S. , Ro H. S. , Kim E. B. , Gilden R. V. , Huebner R. J. 
Published: February 2007

AbstractA horse skin cell line (E. Derm, NBL‐6, CCL‐57) was susceptible to focus formation by the Kirsten mouse sarcoma virus, feline sarcoma virus (ST strain) and the MSV pseudotypes with woolly monkey, gibbon monkey, RD‐114, AT‐124, baboon placenta and murine xenotropic (BALB/c 3T3 and C57L/JD) type‐C viruses. Foci were detected within 5 days after infection and the transformed cells continued to produce infectious virus and group‐specific antigen of their respective type‐C leukemia viruses. The transformation efficiency of various type‐C sarcoma viruses in horse cells was also very high.
Immunological mechanisms in the pathogenesis of virus‐induced murine leukemia. II. Characterization of autoreactive thymocytes
Authors: Proffitt Max R. , Hirsch Martin S. , McKenzie Ian F. C. , Gheridian Beatriz , Black Paul H. 
Published: February 2007

AbstractThe nature of the reaction and the type of effector cells involved in the reactivity of thymocytes from Moloney murine leukemia virus (MuLV‐M)‐carrier mice against normal syngeneic target cells has been further characterized. The reaction is mediated by viable MuLV‐infected thymocytes. Lysates of carrier thymocytes are not more effective in causing target cell reduction than are lysates of normal thymus cells. Soluble mediators do not appear to be involved in the reaction. The thymocytes mediating the reaction are non‐adherent cells positive for the theta‐C3H and H‐2k alloantigens, but are negative for detectable murine IgG determinants. Their resistance to corticosteroid treatment further identifies them as functionally mature immunocytes.
Tumor‐induced angiogenesis: Lack of inhibition by irradiation
Authors: Auerbach Robert , Arensman Robert , Kubai Louis , Folkman Judah 
Published: February 2007

AbstractThe effect of irradiation of tumors on their ability to induce vascular responses (angiogenesis) was studied. Rat Walker carcino‐sarcoma 256, rabbit V2 carcinoma, mouse (C57Bl) melanoma and mouse (129) teratoma (OTT 6050, 100K) were irradiated with up to 5000R, then grafted either to the chicken chorioallantoic membrane or intracorneally into adult rabbits to assess competence to provoke angiogenesis. For all tumors and both assay systems the results were similar: irradiation did not interfere with tumor‐induced vascular responses.