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Objectives. Current primary prostate cell culture techniques use an overnight digestion or extensive media preparation. In this report, we describe a method for the culture of benign and neoplastic cells from human prostatectomy specimens that is rapid and contains no undefined factors in the medium.Methods. Characterization of the human cultured prostate cells was performed using immunohistochemical methods and monoclonal antibodies AE1/AE3 and cytokeratin 8, as well as monoclonal antibodies against prostate-specific antigen (PSA). Polymerase chain reaction was used to measure the exclusive epithelial and stromal cell products, c-met and hepatocyte growth factor (HGF), respectively. Electron microscopy was performed to assess the cell junctions and morphologic features of epithelial cells. Optimum cell growth in different media was tested using a cell replication assay.Results. Microscopic evidence revealed that the cells demonstrate typical epithelial morphology, with polyhedral cells forming tight junctions in a continuous monolayer. Desmosomes were present in electron micrographs of epithelial cells. The cultured epithelial cells described in this report also demonstrate positive cytokeratin staining. The epithelial cells reacted positively with PSA antibody, indicating that the cells retain their secretory role in cell culture for a limited period. Epithelial cells expressed the HGF receptor, c-met; stromal cells secreted HGF. Insulin, transferrin, and selenium increased the growth of cells in the chemically defined media, compared with minimum essential media (MEM) and Ham's F12.Conclusions. In summary, essentially pure cultures of prostate stromal or epithelial cells have been established using simple isolation and culture methods. These cells will be useful for the investigation of related growth factors, such as insulin-like growth factor I and insulin-like growth factor II, and in understanding the basis for stromal-epithelial cell interactions.  相似文献   
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The interleukin 4 (IL 4) receptor is expressed on various cells of the immune system, including T and B lymphocytes, macrophages and mast cells. We have constructed a recombinant protein, DAB389-mIL 4, that is composed of the enzymatically active and membrane translocation domains of diphtheria toxin fused to murine IL 4. We demonstrate that this fusion toxin selectively inhibits protein synsthesis in eukaryotic cells which express the murine IL 4 receptor. The cytotoxic potency of this fusion toxin is shown to be directly proportional to the reported number of IL 4 receptors on the surface of target cells. Since the action of DAB389-mIL 4 can be blocked with either excess mIL 4 or antibody to mIL 4, we conclude that its entry into target cells is mediated through the mIL 4 receptor. A mutant form of DAB389-mIL 4, DA(197)B389-mIL 4, in which the fragment A-associated ADP-ribosyltransferase is inactive, is not cytotoxic to murine IL 4 receptor-bearing cells. Finally, we demonstrate that DAB389-mIL 4 administered subcutaneously to DBA/2 mice results in suppression of delayed-type hypersensitivity (DTH); whereas, the non-toxic DA(197)B389-mIL 4 fails to dampen the DTH response.  相似文献   
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The murine antibody response to Escherichia coli beta-galactosidase (GZ) was analyzed in vivo and in vitro by focusing on two families of antibodies that exert distinct conformational/functional activity on the antigen. Activating antibodies--defined by their capacity to increase the enzymatic activity of defective GZ produced by mutant strains of E. coli--are detected early after secondary challenge. Inhibiting antibodies, which interfere with antibody-mediated enzyme activation, appear later and cause the abrupt fall of activating titer, a scenario suggesting either idiotype/anti-idiotype interaction or opposite pulsions exerted on the antigen molecule. Supporting the latter mechanism, the confrontation of mAbs of the two families produced classical competitive inhibition curves when the readout was enzyme activation, although they recognize two different epitopes of the same molecule: the activating mAb a quaternary conformation-dependent site of wild-type GZ, the inhibiting mAb a sequential determinant exposed only in denatured or in defective enzyme. The different timing of generation of these antibodies during the response may depend on a processing step necessary for unfolding of native antigen and consequent display of certain cryptic epitopes before they can trigger specific B cells. A picture emerges where the response to the various epitopes of a complex antigen is sequentially connected and where the uptake by antigen-presenting cells of antigen complexed with antibodies specific for the exposed epitopes may favor revelation of the cryptic ones.  相似文献   
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Evidence accumulating from a variety of methodological approaches suggests that unusual laterality is often a concomitant feature of emotional pathology. In the present study both torque and a multifaceted measure of laterality were examined with respect to personality variables measured by the 16 PF in a normal population. Interestingly, a pattern of emotionality for subjects with a more confused laterality was revealed in a normal population which is notably similar to reported aberrant personality factors and laterality in more pathological groups. The existence of a cohesive continuum of emotional expression in relation to confused laterality is suggested. In addition, both torque and the multifactored measure of laterality are critiqued as research measures and for their clinical potential.  相似文献   
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The present study was undertaken to assess the temporal association between the profiles of serum concentrations of oestradiol-17beta, progesterone, chorionic gonadotrophin (CG) and relaxin in pregnancies established naturally, and after embryo transfer, as well as in failed pregnancies in rhesus monkeys. In naturally mated cycles (group 1) a conception rate of 75% was obtained. In group 1, the mean day of CG detection in serum was 11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day post-ovulation. In group 2, embryo transfer to synchronous, non-mated surrogate recipients was performed; seven embryo transfer cycles yielded three pregnancies which were allowed to continue to term and normal infants were delivered. In embryo transfer cycles the mean day of CG detection was 14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day post-ovulation. A delay of about 3 days was observed in the appearance in circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between natural mated and embryo transfer conception cycles. Significant differences (P < 0.05 for progesterone and P < 0.03 for oestradiol) were obtained for the areas under the curves for progesterone and oestradiol between days 12 and 16 in conception cycles compared with failed pregnancies. These data provide the first observation of the normal hormonal signals associated with maternal recognition of transferred embryos during the peri- implantation period, and suggest that the use of such an experimental primate embryo transfer model may help to elucidate components of maternal and embryonic signal-response mechanisms during embryo implantation.   相似文献   
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