bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coffee consumption and risk of pancreatic cancer
Authors: La Vecchia Carlo , Liati Paola , Decaru Adriano , Negri Eva , Franceschi Slivia 
Published: February 2007

AbstractThe relationship between pancreatic cancer and coffee, decaffeinated coffee and tea drinking habits was evaluated using data from a hospital‐based case‐control study conducted in Northern Italy on ISO histologically confirmed cases and 605 controls with acute, non‐neoplastic, other than digestive tract diseases unrelated to coffee consumption or to any of the known or potential risk factors for cancer of the pancreas. Compared with subjects who did not drink coffee, the multivariate relative risks were 1.7 for those who drank less than 2 cups per day, but only 1.4, and 1.1 respectively for drinkers of 3 or 4 and 5 or more cups. Likewise, there was no association with duration of consumption of coffee, decaffeinated coffee or tea. These findings were reviewed together with published evidence from other case‐control studies (or cohort studies analyzed as case‐control) of coffee and pancreatic cancer. When appropriate statistical methods were used to pool information, and the data from the first study which was the basis of the hypothesis were omitted, the relative risk of pancreatic cancer based on 1,464 cases was 1.2 for moderate coffee drinkers and 1.4 for heavy drinkers, and we suspect that at least part of this moderate residual association is confounded by cigarette smoking. Thus, although the present investigation and a general overview of published epidemiological evidence are compatible with a small effect of coffee on pancreatic carcinogenesis, interpretation of these findings is not obvious on account of the possibility of residual confounding and other sources of bias.
Immunological analysis of mucin molecules expressed by normal and malignant mammary epithelial cells
Authors: Griffiths Andrew B. , Burchell Joy , Gendler Sandra , Lewis Angela , Blight Ken , Tilly Rita , Taylor‐Papadimitriou Joyce 
Published: February 2007

AbstractMany existing MAbs raised against the human milk fat globule or against carcinoma cells recognise epitopes on high‐molecular‐weight glycoproteins. In a comparative ELISA assay a number of these antibodies have been shown to react with an extract of the human milk fat globule. In comparative immunoblots of cultured normal milk cells and breast cell lines, all were found to bind to large molecules which show some variation in molecular weight depending on the cell source. The HMFG‐2 antibody, which is widely used in cancer diagnosis, also recognises epitopes on lower‐molecular‐weight components. In T47D cells these may be as small as 80,000 Mr, and with electron microscopy this cell line can be shown to accumulate HMFG‐2‐reactive components in the Golgi apparatus. Using an HMFG‐2 affinity column we have immunopurified HMFG‐2‐reactive material from the 2 breast cancer cell lines MCF‐7 and T47D and shown that all of the above antibodies react in a solid‐phase ELISA with the purified material. In addition to high‐molecular‐weight components, the immunopurified material was found to contain lower‐molecular‐weight components including a glycoprotein of 68,000 Mrthat was not, however, recognised by the HMFG‐2 antibody on a Western blot. We have used this immunopurified material to generate new MAbs. All of these recognise the high‐molecular‐weight bands seen with the other antibodies, but 2 of them also recognise a band at 68,000 Mr in blots of MCF‐7 and T47D. The Second‐generation antibodies show a spectrum of reactivity on tissues similar to HMFG‐2 and one reacts at least as strongly as HMFG‐2 with methanol‐acetone‐fixed sections of breast cancers.
Aflatoxin detected in human breast milk by immunoassay
Authors: Wild Christopher P. , Pionneau Florence A. , Montesano Ruggero , Mutiro Crispen F. , Chetsanga Christopher J. 
Published: February 2007

AbstractSeveral epidemiological studies have shown a positive association between dietary exposure to aflatoxin (AF) and an increased incidence of primary hepatocellular carcinoma (PHC). One area in which little information is available is the exposure of newborn children to AF in human breast milk. We report the development, validation and application of an enzcyme‐linked immunosorbent assay (ELISA) to the detection of AF in human breast milk. The assay allows the quantitation of 2 pg AFM, per ml of milk using less than 10 ml of sample. A good correlation was observed between ELISA and an hplcfluorescence technique using naturally contaminated milk at levels up to 40 pg AF per ml. Of 54 samples collected from women in rural villages in Zimbabwe, 6 were found to be positive (11 %) in ELISA with levels up to 50 pg AF per ml. No positive samples were detected out of 42 milk samples obtained from women in France. This sensitive and rapid methodology will be useful in examining the importance of and interaction between exposure to AF and infection with hepatitis B virus (HBV) early in life.
Cultured stem‐cells from human testicular teratomas: The nature of human embryonal carcinoma, and its comparison with two types of yolk‐sac carcinoma
Authors: Pera Martin F. , Lafita M. J. Blasco , Mills Judith 
Published: February 2007

AbstractThe understanding of differentiation in human teratomas requires a better definition of the phenotype and developmental potential of the stem cells in these tumours. We describe the characterization of 6 new cell lines from human t asticular teratomas which are representative of 3 distinct cell types. Cell lines GCT 27, GCT 35, and GCT 48, identified as embryonal carcinoma, comprise epithelial cells which express cytokeratin intermediate filaments and desmoplakins, as' determined by indirect immunofluorescence microscopy. A minority of the cells also express vimentin. Most cells in these cultures show surface staining with monoclonal antibodies (MAbs) to stage‐specific embryonic antigens SSEA 3 and SSEA 4 but not SSEA 1. Staining with MAb W6/32, which recognizes HLA A,B and C chains in the presence of β‐2 microglobulin, is not above background level. When injected into nude mice, GCT 27 cells form tumours consisting of embryonal carcinoma, somatic tissues, and cells positive in immunocytochemical assays for alphafoetoprotein (AFP) and human chorionic gonadotrophin (HCG); GCT 35 cells form embryonal carcinomas with foci of AFP and HCG‐positive cells; and GCT 48 cells form embryonal carcinoma only. A second type of cell (GCT 72) displays some properties of rodent visceral endoderm. GCT 72 cells contain cytokeratin intermediate filaments, but not vimentin, and show very strong staining at cell borders with anti‐desmoplakin 1 + 11 antibody. At the cell surface, GCT 72 cells express the epitopes recognized by antibodies to SSEA 3, SSEA 4, and SSEA 1; staining with W6/32 is negligible. Levels of AFP in supernatants from GCT 72 cultures are in excess of 500 KIU/1. The tumours formed following inoculation of nude mice with GCT 72 cells are solid yolk‐sac tumours, with all cells strongly positive for AFP. A third cell type (GCT 44 and GCT 46), resembles in some ways rodent parietal endoderm. These cells uniformly coexpress keratin and vimentin intermediate filaments, but not desmoplakins. The determinants recognized by MAbs to SSEA 3, 4, or 1 are not detected on the majority of cells in these cultures. In striking contrast to the other teratoma lines, these cells can attach to untreated tissue culture plastic in serum‐free medium and may be serially cultivated under these conditions. The tumours formed in nude mice by these 2 cell lines are yolk‐sac carcinomas with endodermal sinus tumour histology. Thus, human testicular teratomas consist of epithelial cells which may be nullipotent, pluripotent or committed to extraembryonic endodermal differentiation. The phenotype of human embryonal carcinoma cells shares some common features with the progenitors of extraembryonic endoderm in the mouse.
Antibody response against the Epstein‐Barr virus‐coded nuclear antigen2 (EBNA2) in different groups of individuals
Authors: Seigneurin J. M. , Lavoue M. F. , Genoulaz O. , Bornkamm G. W. , Lenoir G. M. 
Published: February 2007

AbstractSpecific antibody responses against the 2 major subcomponents of EBNA, EBNAI and EBNA2 were evaluated, in order to study whether this serological study was beneficial compared to classical EBV serology. During this investigation, 491 sera, obtained from blood donors and patients with Burkitt's lymphoma (BL), nasopharyngeal carcinoma (NPC), infectious mononucleosis (IM), Hodgkin's disease, renal transplantation, rheumatoid arthritis and Human Immunodeficiency Virus (HIV) infection, were tested. While the anti‐EBNAI response followed the classical anti‐EBNA/Raji response (99% of anti‐EBNA/Raji‐positive sera also recognize EBNAI), the anti‐EBNAI response was much less frequent and did not correlate with either anti‐EBNA/Raji or anti‐EA antibodies. In a control population, 8% of individuals had anti‐EBNAZ antibodies at titers ≥ 10. The percentage was 45% In NPC and 38% in EBV‐associated BL; thus, although not detected in all patients with EBV‐associated tumors, anti‐EBNA2 serology might be a useful marker in BL and NPC. No antibody was detected in the early course of IM, but in rheumatoid arthritis and in HIV‐infected patients, the percentage of positive individuals reached 54 and 68, respectively. Seroconversion to EBNA2 was noted in a few cases, including renal transplant recipients, AIDS patients, and complicated IM. This suggests that in these situations, EBNA 2 serology might represent a useful marker related to modulation of the immune status or EBV reactivation.
Down‐regulation of the EBV‐encoded membrane protein (LMP) in burkitt lymphomas
Authors: Hatzubai A. , Anafi M. , Masucci Maria Grazia , Dillner J. , Lerner R. A. , Klein G. , Suutzeanu D. 
Published: February 2007

AbstractA radioimmunoassay (RIA) has been developed and used to determine the expression of LMP—a membrane protein encoded by the LT3 region of the Epstein‐Barr virus (EBV) genome—in cell lines of various origins. The RIA was highly sensitive, specific and reproducible. All EBV‐negative cell lines were LMP‐negative and 18 of 21 EBV‐carrying cells were LMP‐positive. LMP concentrations varied widely, ranging approximately from less than 4 ng up to 650 ng/mg protein. In several instances comparisons were made between lymphoblastoid (LCLs) and Burkitt lymphoma (BL) cell lines (EBV‐positive or EBV‐co wetted sublines of originally EBV‐negative BL) originating from the same patient. In all such cases LMP and LMP‐specific mRNA levels were higher in the LCLs. Most of the LMP was found in the cytosol fraction, yet this fraction was negative in immunoblotting tests. However, antiserum preincubated with the cytosol lost its ability to react in immunoblotting with membrane LMP, indicating that the 2 LMP forms (membrane and cytosol) are completely cross‐reactive.
In vivo anti‐tumor activity of combinations of interferon alpha and interleukin‐2 in a murine model. Correlation of efficacy with the induction of cytotoxic cells resembling natural killer cells
Authors: Brunda Michael J. , Bellantoni Donna , Sulich Viveca 
Published: February 2007

AbstractThe in vivo anti‐tumor activity of 2 recombinant cytokines, interleukin‐2 (rIL‐2) and human hybrid interferon alpha (rHuIFN‐αA/D), were tested using the murine reticulum cell sarcoma M5076. Experimental hepatic metastases, following i.v. injection of tumor cells, and tumor growth and spontaneous metastases, following s.c. injection of tumor cells, were inhibited to a greater extent in mice treated with a comblnation of these cytokines than in animals treated with either one alone. When used in conjunction with surgical removal of the s.c. tumor, treatment of mice with both cytokines significantly prolonged survival of tumor‐bearing animals. Injection of normal mice with a combination of cytokines, but not with either cytokine alone, resulted in a marked increase in cytotoxic activity of hepatic effector cells. The effector cells in these mice appeared to be NK cells since this enhanced cytotoxicity was markedly reduced in animals treated in vivo with anti‐asialo GM1 or in NK‐deficient beige mice. Furthermore, no in vivo efficacy was observed in M5076‐bearing beige mice treated with these cytokines. Thus, injection of mice with rIL‐2 and rHuIFN‐αA/D results in the induction of an NK‐cell‐like population in the liver with enhanced cytotoxic activity that correlates with the observed anti‐tumor activity in vivo in this murine model. These results suggest that combinations of cytokines, in particular IFN‐α and IL‐2, can be effectively used in combination for the treatment of tumors and/or metastases.
MHC‐controlled susceptibility to C3H‐MTV‐induced mouse mammary tumors is predominantly systemic rather than local
Authors: Dux A. , Demant P. 
Published: February 2007

AbstractThe major histocompatibility complex (MHC) is one of the genetic factors involved in the control of susceptibility to MTV‐induced mammary tumors in mice. Previously, genetic differences in mammary tumor susceptibility were shown to be mainly due to differences in susceptibility of the mammary gland itself. Such experiments, however, were carried out using inbred strains which differ in many genes. Therefore, the conclusion drawn from such experiments is not necessarily applicable to every gene involved.We tested whether in the strain C57BL/10 (B10, resistant) and the H‐2 congeneic strain B10. A(5R) (SR, susceptible), which differ only at the MHC, the MHC‐controlled difference in tumor susceptibility indeed resides in the mammary gland tissue itself, or is caused by systemic factors. Mammary glands of infant B10 and 5R mice were transplanted into mammary fat pads of C3H‐MTV‐infected mammectomized (B10 × 5R)F1 females. The hosts received a hypophyseal isograft under the kidney capsule or were subjected to force‐breeding to provide hormonal stimulation necessary for mammary tumor development. Control groups of C3H‐MTV‐infected B10, 5R and (B10 × 5R)F1 females and (B10 × 5R)F1 females without C3H‐MTV were also subjected to the 2 types of hormonal stimulation. There was no difference in susceptibility between the 5R and BIO mammary glands transplanted into C3H‐MTV‐infected F, hybrid hosts. On the other hand, C3H‐MTV‐infected 5R and (B10 × 5R)F1 females were significantly more susceptible than the C3H‐MTV‐infected B10 females, when either of the 2 methods of hormonal stimulation was used. This indicates that, in the strains used, MHC‐controlled susceptibility to C3H‐MTV‐induced mammary tumorigenesis is predominantly or exclusively controlled by systemic factors rather than by factors residing in the target tissue.
Suppression of NK activity of spleen cells by chicken fetal antigen present on Marek's disease lymphoblastoid cell line cells
Authors: Ohashi Kazuhiko , Mikami Takeshi , Kodama Hiroshi , Izawa Hisao 
Published: February 2007

AbstractChicken fetal antigen (CFA) expressed on the cell surface of Marek's disease (MD) lymphoblastoid cell line (MDCC‐MSBI) cells was purified by affinity chromatography using a monoclonal antibody (2H3). A 4‐hr 51Cr release assay was performed using spleen cells as effector cells to investigate the role of the CFA in the immune response of chickens, especially in relation to natural killer (NK) activity. Spleen cells of specific‐pathogen‐free (SPF) chickens showed reduced NK activity in the presence of CFA in vitro, as did those cells treated with MSBI soluble antigen. NK activity of spleen cells from chickens treated with CFA was also suppressed when compared to the cells from untreated or ovalbumin‐treated chickens. In addition, MSBI clo. 18 transplantable tumors grew progressively in some of the 14‐day‐old chickens treated with CFA, whereas the tumors regressed in age‐matched chickens with or without treatment by ovalbumin.
Stable transfection of a human lymphoma line by sub‐genomic fragments of Epstein‐Barr virus DNA to measure humoral and cellular immunity to the corresponding proteins
Authors: Welinder Christina , Larsson Nils‐Göran , Szigeti Robert , Ehlin‐Henriksson Barbro , Henle Gertrude , Henle Werner , Klein George , Ricksten Anne , Rymo Lars , Sulitzeanu Dov 
Published: February 2007

AbstractAn Epstein‐Barr virus (EBV)‐negative human lymphoid B‐cell line, DG75, was stably transfected with recombinant selection vectors that carry a subfragment of the BamHI WYH region (nucleotides 44664 to 50628), the BamHI K fragment, or a subfragment of the EcoRI D region (nucleotides 166614 to 170149) of B95‐8 EBV DNA. These fragments contain the coding exons for the EBV‐determined nuclear antigens EBNA2 and EBNA1, and the membrane antigen LMP, respectively. Antigen expression of the cells was detected by immunofluorescence. EBNA2 was expressed in 80–100% of the transfected cells, in contrast to EBNA1 which was expressed in only 25%, and LMP in only about 5% of the cells. Humoral antibody responses were measured by immunofluorescence and compared to cellular immunity as determined by the leukocyte migration inhibition (LM1) technique. Extracts from transfected cell lines expressing EBNA1, EBNA2 or LMP elicited an LMI response with cells from healthy EBV‐seropositive individuals whereas the extract from the parental DG75 cell line did not, The results demonstrate the value of stably transfected cell lines expressing a defined EBV antigen for the monospecific analysis of host responses to the EBV‐encoded antigen complex in growth‐transformed cells.
Cell shape modulation alters glycosylation of a metastatic melanoma cell‐surface antigen
Authors: Nabi Ivan R. , Raz Avraham 
Published: February 2007

AbstractB16‐F1 melanoma cells cultivated in vitro as spheroids on a non‐adhesive substrate acquire in a reversible fashion an increase in lung colonization in vivo as compared to cells cultured as a monolayer. After neuraminidase treatment of protein blots, the spheroidal cells expressed an increased binding of 125I‐labelled peanut lectin (PNA) to a unique glycoprotein of Mr78,000 (gp78) which after desialylation migrated in SDS‐polyacrylamide gels as an Mr86,000 protein. Antibodies were generated against this glycoprotein purified on PNA‐Sepharose and its expression on the surface of viable B16‐F1 cells was demonstrated. Growth of B16‐F1 melanoma cells in suspension is associated with the altered glycosylation of gp78 which may be related to the increased metastatic ability of these cells. In vitro treatment of B16‐F1 cells with anti‐gp78 Fab fragments prior to their injection into the tail veins of syngeneic mice resulted in a 2‐fold increase in the appearance of tumor lung colonies.
Protection of cynomolgus monkeys against infection by human T‐cell leukemia virus type‐I by immunization with viral env gene products produced in Escherichia coli
Authors: Nakamura Hideo , Hayami Masanori , Ohta Yoshihiro , Ishikawa Koh‐Ichi , Tsujimoto Hajime , Kiyokawa Tetsuyuki , Yoshida Mitsuaki , Sasagawa Akira , Honjo Shigeo 
Published: February 2007

AbstractProtection against human T‐cell leukemia virus type‐1 (HTVL‐1) infection in cynomolgus monkeys, achieved by immunizing the animals with env gene products of HTLV‐I produced in Escherichia coll, was evaluated. Four monkeys that had been immunized with the env product produced antibody against HTLV‐I gp68 and gp46, and their sera were found to cause strong inhibition of syncytium formation of a cat fibro‐blast cell line induced by HTLV‐I. Immunized and non‐immunized monkeys were challenged with live MT‐2 cells, a high HTLV‐I‐producer cell line. After challenge, all the control nonimmurized monkeys were infected with HTLV‐I, as judged by the frequent detection of HTLV‐I‐antigens in cultures of their peripheral blood mononuclear cells (PBMC), whereas no antigens were recovered from PBMC of immunized monkeys. These results indicate that humoral immunity against HTLV‐I‐envelope protein elicited by immunization with the polypeptides synthesized in bacteria protected the monkeys against primary infection with HTLV‐I.
Activation of endogenous MMTV proviruses in murine mammary cajncer induced by chemical carcinogen
Authors: Knepper Janice E. , Medina Daniel , Butel Janet S. 
Published: February 2007

AbstractA study was undertaken to determine whether activation of expression of silent endogenous mouse mammary tumor virus (MMTV) proviruses may occur during tumor induction by a chemical carcinogen. A series of transplantable mammary tumors induced in BALB/c mice by treatment with dimethylbenz(α)anthracene (DMBA), pituitary isograft, or both was examined. The results obtained suggest that chemical carcinogens may induce mammary tumors through more than one pathway. Two of 9 tumor lines produced virus‐specific products at levels above those observed during the Course of normal mammary gland development. One tumor contained high levels of MMTV‐specific envelope [3.8 kilobase (kb)] and genomic length (8.9 kb) RNAs. This tumor expressed core‐and envelope‐related proteins detectable by immuno‐blotting (including p28, gp52, and gp36), displayed an acquired provirus with a restriction map different from those of described exogenous MMTV strains, and contained abundant virus particles. The other tumor that expressed high levels of MMTV gene products contained envelope‐specific (3.8 kb) and long‐terminal‐repeat‐specific (1.6 kb) messages but no full‐length RNA. It exhibited an aberrant 39 kDa, envelope‐related protein, but no virus particles. Methylation data implicated the usually silent endogenous Mtv‐8 provirus as the source of the abnormal envelope protein. None of the tumors expressed RNA from the putative mammary oncogenes, int‐1 or Int‐2. We propose that chemical carcinogens may activate different cellular genes by mutation and that, in a subset of DMBA‐induced mammary tumors, the target genes include endogenous MMTV proviruses that are normally not expressed. The effect on provirus expression varies from tumor to tumor, but is stable over passage of a given tumor. MMTV may be of etiological importance in the genesis of those DMBA‐induced tumors which contain high levels of MMTV‐specific products, but its action in the BALB/c system is not mediated through enhanced expression of the int‐1 or int‐2 preferred integration regions.