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Protein kinase C: a new linkage marker for growth hormone and for COL1A1   总被引:1,自引:0,他引:1  
An expanded linkage group on the long arm of human chromosome 17 is reported. Using the CEPH panel of DNAs and restriction fragment length polymorphism (RFLP) markers for the centromere locus (D17Z1), growth hormone (GH1), collagen type I alpha 1 (COL1A1), and protein kinase C-alpha polypeptide (PKCA) loci, theta values of 0.03, 0.11, and 0.23 were found between PKCA and GH1, PKCA and COL1A1, and PKCA and D17Z1, respectively. The theta values calculated for GH1 versus COL1A1 or D17Z1 were 0.11 and 0.23, respectively. Sex-specific recombination rates were calculated for the best likelihood order and demonstrate female recombination greater than male recombination. Therefore, the loci studied span a map region of approximately 30 cm between 17cen and 17q24, with the most likely gene order being D17Z1-COL1A1-PKCA-GH1.  相似文献   
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Hormonal imprinting takes place at the first encounter of the hormone and receptor, and results in a changed binding capacity and reaction of the cell and its progeny generations. The imprinting effect of three amino acids and their oligopeptides is studied using fluorescent-labelled peptides. Glycine and lysine could provoke positive imprinting (increased binding in the progeny generations) for their own peptides, but alanine could not. Mostly positive imprinting was provoked by glycine and lysine peptides for their own peptides of different chain length. The optimal chain length provoking self-imprinting was four for glycine, two for lysine and three for alanine. Except in this case, alanine was neutral or provoked mostly negative imprinting. After reaching the optimal chain length, there is a decline in binding. Evolutionary conclusions are discussed.  相似文献   
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Summary The effects of progesterone pretreatment on in vivo 3H-estrogen uptake by five anterior pituitary cell types was analyzed by means of a quantitative autoradiographic-immunocytochemical technique. Male and female rats castrated for 14 days show nuclear concentration of label in all five cell types one h after injection of 3H-estradiol, whether progesterone treated or not. The order of labeling intensity is gonadotropes lactotropes = somatotropes > thyrotropes = corticotropes. Progesterone treatment induces a dramatic sexual dimorphism in estrogen uptake; it significantly increases 3H-estrogen uptake in all female cell types. In males, progesterone decreases uptake in gonadotropes while not altering uptake in other cell types.Supported by PHS grant HD 12173 and Research Career Development Award HD 00243. Portions of these data were presented at the American Association of Anatomists meeting, Omaha, 1980I wish to acknowledge Mr. Sing Kung Lau for his excellent technical assistance and Dr. P. Rodier for her advice and assistance with the statistical analyses. I also wish to thank Dr. A.F. Parlow and NIAMDD for antisera against rLH, hFSH, rPRL and rTSH and Dr. Peter Petrusz, University of North Carolina, for antisera against bGH and h endorphin  相似文献   
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To analyze the signaling pathways utilized in malignant transformation by pp60v-src, we have isolated and characterized src mutants which possess normal levels of protein tyrosine kinase activity but which cause only a partially transformed phenotype. Our hypothesis is that such mutants are partially defective for transformation because they are defective in their ability to activate specific components of the cellular signaling machinery while still activating others. In this communication, we report on the molecular and biochemical characterization of one such mutant, CU12 (D. D. Anderson, R. P. Beckmann, E. H. Harms, K. Nakamura, and M. J. Weber, J. Virol. 37:455-458, 1981). Cells infected with this mutant are capable of anchorage-independent growth, but rather than exhibiting the rounded and refractile morphology characteristic of wild-type-infected cells, they display an extremely elongated, fusiform morphology. The morphological properties of this mutant src could be accounted for entirely by a single mutation in the SH3 domain (lysine 106 to glutamate). Other mutations were constructed in this region by in vitro mutagenesis, both in a v-src and in an activated c-src background, and several of them also induced a fusiform morphology. All of the mutations inducing fusiform morphology also resulted in decreased association of pp60src with phosphatidylinositol 3'-kinase activity. In addition, association of pp60src with some tyrosine-phosphorylated proteins was altered. We propose that the SH3 domain participates (along with the SH2 domain) in the interaction of pp60src with cellular signaling proteins, and we speculate that the association with phosphatidylinositol 3'-kinase plays an important role in the regulation of cellular morphology.  相似文献   
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Summary Dry-mount autoradiography was combined with peroxidase immunocytochemistry to examine estrogen uptake in four pituitary cell types. Quantification by silver grain counts was used to compare 3H-estradiol uptake in nuclei of pituitary cells 60 min after i.v. injection into short-term (control) and long-term ovariectomized and in long-term thyroidectomized rats. Under all three hormonal states, the order of labeling intensity was: gonadotropes > somatotropes > lactotropes > thyrotropes. Long-term ovariectomy caused a significant increase in estrogen uptake of gonadotropes, somatotropes and lactotropes, while uptake in thyrotropes decreased. Long-term thyroidectomy decreased uptake in somatotropes, lactotropes and thyrotropes while gonadotropes remained unchanged.Supported by NICHHD grant HD-03007 to D.A.K., NICHHD grant HD-03110 to the Biological Sciences Research Center of Child Development Research Institute and a grant from the Rockefeller Foundation to the Laboratories for Reproductive Biology.  相似文献   
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When an γ‐irradiated Dy‐, Tm‐, Sm‐ or Mn‐doped CaSO4 crystal is impulsively deformed, two peaks appear in the ML intensity versus time curve, whereby the first ML peak is found in the deformation region and the second in the post‐deformation region of the crystals. In this study, intensities Im1 and Im2 corresponding to first and second ML peaks, respectively, increased linearly with an impact velocity v0 of the piston used to deform the crystals, and times tm1 and tm2 corresponding to the first and second ML peaks, respectively, decreased with impact velocity. Total ML intensity initially increased with impact velocity and then reached a saturation value for higher values of impact velocity. ML intensity increased with increasing γ‐doses and size of crystals. Results showed that the electric field produced as a result of charging of newly‐created surfaces caused tunneling of electrons to the valence band of the hole‐trapping centres. The free holes generated moved in the valence band and their subsequent recombination with electron trapping centres released energy, thereby resulting in excitation of luminescent centres. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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Background: Colorectal carcinogenesis is believed to be a multi-stage process that originates with a localized adenoma, which linearly progresses to an intra-mucosal carcinoma, to an invasive lesion, and finally to metastatic cancer. This progression model is supported by tissue culture and animal model studies, but it is difficult to reconcile with several well-established observations, principally among these are that up to 25% of early stage (Stage I/II), node-negative colorectal cancer (CRC) develop distant metastasis, and that circulating CRC cells are undetectable in peripheral blood samples of up to 50% of patients with confirmed metastasis, but more than 30% of patients with no detectable metastasis exhibit such cells. The mechanism responsible for this diverse behavior is unknown, and there are no effective means to identify patients with pending, or who are at high risk for, developing metastatic CRC.Novel findings: Our previous studies of human breast and prostate cancer have shown that cancer invasion arises from the convergence of a tissue injury, the innate immune response to that injury, and the presence of tumor stem cells within tumor capsules at the site of the injury. Focal degeneration of a capsule due to age or disease attracts lymphocyte infiltration that degrades the degenerating capsules resulting in the formation of a focal disruption in the capsule, which selectively favors proliferating or “budding” of the underlying tumor stem cells. Our recent studies suggest that lymphocyte infiltration also triggers metastasis by disrupting the intercellular junctions and surface adhesion molecules within the proliferating cell buds causing their dissociation. Then, lymphocytes and tumor cells are conjoined through membrane fusion to form tumor-lymphocyte chimeras (TLCs) that allows the tumor stem cell to avail itself of the lymphocyte''s natural ability to migrate and breach cell barriers in order to intravasate and to travel to distant organs. Our most recent studies of human CRC have detected nearly identical focal capsule disruptions, lymphocyte infiltration, budding cells, and the formation of TLCs. Our studies have further shown that age- and type-matched node-positive and -negative CRC have a significantly different morphological and immunohistochemical profile and that the majority of lymphatic ducts with disseminated cells are located within the mucosa adjacent to morphologically normal appearing epithelial structures that express a stem cell-related marker.New hypothesis: Based on these findings and the growth patterns of budding cells revealed by double immunohistochemistry, we further hypothesize that metastatic spread is an early event of carcinogenesis and that budding cells overlying focal capsule disruptions represent invasion- and metastasis-initiating cells that follow one of four pathways to progress: (1) to undergo extensive in situ proliferation leading to the formation of tumor nests that subsequently invade the submucosa, (2) to migrate with associated lymphocytes functioning as “seeds” to grow in new sites, (3) to migrate and intravasate into pre-existing vascular structures by forming TLCs, or (4) to intravasate into vascular structures that are generated by the budding cells themselves. We also propose that only node-positive cases harbor stem cells with the potential for multi-lineage differentiation and unique surface markers that permit intravasation.  相似文献   
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