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151.
R Sprengel B Suchanek C Amico R Brusa N Burnashev A Rozov O Hvalby V Jensen O Paulsen P Andersen JJ Kim RF Thompson W Sun LC Webster SG Grant J Eilers A Konnerth J Li JO McNamara PH Seeburg 《Canadian Metallurgical Quarterly》1998,92(2):279-289
The definitive function of pancreatic polypeptide in mammalian physiology remains unknown. The identification of specific PP target tissues should be helpful to further investigations into the possible regulatory actions of this peptide. An in vivo radioreceptor assay was used in the rat to locate potential binding sites of I(125) bovine PP. In vitro, high concentrations of unlabeled hormone competitively inhibit binding to receptors by low concentrations of labeled hormone. In vivo studies showed that, in the presence of concentrated unlabeled pancreatic polypeptide, labeled PP distributes between the plasma and interstitial fluid. When excess unlabeled PP is replaced with saline in the companion animals, the labeled peptide appears to distribute in a volume that exceeds the combined plasma volume and interstitial fluid volume of the tissue. Using this in vivo receptor assay, the distribution volume that exceeds the anatomic extracellular volume has been identified as the receptor compartment. With this assay we demonstrated in the rat specific and displaceable PP binding to the ductus choledochus, duodenum, ileum, and adrenal gland. The NVV determined in the adrenal gland of experimental animals was 3.9 times greater than that found in the control group. Binding was rapid and was displaced only by excess unlabeled pancreatic polypeptide. Neither excess insulin nor excess neuropeptide Y significantly reduced this binding. 相似文献
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Twenty-five genes have been identified in which mutations cause epileptic seizures in mice. The gene for a Na+/H+ exchanger has recently been found to underlie the spontaneous mutant slow wave epilepsy. Studies of such mutants should help elucidate the mechanisms that control neuronal excitability. 相似文献
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Databases for monitoring patients with contact dermatitis have become indispensable for managing a constantly increasing variety of products which cause allergic and toxic dermatitis. As a result of collaboration between the Department of Dermatology and Department of Information Technology, Ullev?l Hospital, we now have developed a database for registering patients with occupational dermatitis. The programming tool is DataEase, which contains files for the patients' personal data, site of the dermatitis, results of tests and diagnosis. 相似文献
157.
JO Ojwang AF Lewis GR Revankar D Walker T Akiyama ME Hogan RF Rando 《Canadian Metallurgical Quarterly》1997,7(5):447-459
Tumor necrosis factor-alpha (TNF-alpha) is a highly pleiotropic cytokine produced mainly by activated macrophages. This cytokine has been found to mediate the growth of certain tumors, the replication of HIV-1, septic shock, cachexia, graft-versus-host disease, and autoimmune diseases. The binding of TNF-alpha to the p55 tumor necrosis factor receptor type I (TNFRI) is considered one of the initial steps responsible for the multiple physiologic effects mediated by TNF-alpha. The role of TNF-alpha as an inflammatory mediator through TNFRI makes both of these genes attractive targets for intervention in both acute and chronic inflammatory diseases. We have designed antisense oligodeoxynucleotides (ODNs) containing chemically modified purine and pyrimidine bases that specifically inhibit TNFRI expression and functions. These ODNs were designed to hybridize to the 3'-polyadenylation signal region of the TNFRI gene. In cell-based assays, gene-specific antisense inhibition occurred in a dose-dependent fashion at submicromolar concentrations in the presence of cellular uptake enhancing agents. Within ODN sets with a common pattern of stabilizing backbone substitution, the inhibition of the gene expression is found to be correlated with the affinity of the ODNs for their cognate mRNA target sites, providing direct evidence for an antisense mechanism of action. In addition, events triggered by the binding of TNF-alpha to TNFRI, such as the production of IL-6 and IL-8, were significantly reduced by treatment of cells with the anti-TNFRI ODN. Therefore, antisense ODNs can be used to control biologic processes mediated by TNF-alpha and may be useful as therapeutic agents to treat conditions resulting from overproduction of TNF-alpha. 相似文献
158.
LF Wang DB Scanlon JA Kattenbelt JO Mecham BT Eaton 《Canadian Metallurgical Quarterly》1994,204(2):811-814
The 349-amino-acid major core protein VP7 of bluetongue virus (BTV) is both the most abundant viral structural protein and the major immunogenic serogroup-reactive viral antigen. Previous studies indicated that a conformation-dependent antigenic site, defined by the VP7-specific monoclonal antibody 20E9/B7/G2(20E9), was accessible from the virus surface and that the binding of the monoclonal antibody to this epitope could be blocked specifically by antisera raised against different serotypes of bluetongue virus, suggesting it is a serogroup-specific immunodominant epitope. Using a combination of three different mapping strategies, we have located the 20E9 binding site at the N-terminus of the molecule, between amino acids 30 and 48. The fine mapping of the 20E9 immunodominant epitope will facilitate structure-function analyses of the major core protein and provide new opportunities to improve existing BTV serodiagnosis methods based on this immunogenic site. 相似文献
159.
A Kessinger MR Bishop JD Jackson B O'Kane-Murphy JM Vose PJ Bierman EC Reed PI Warkentin JO Armitage JG Sharp 《Canadian Metallurgical Quarterly》1995,23(7):609-612
A trial to determine the usefulness of recombinant human erythropoietin (rhEpo) as a mobilizing cytokine for patients with previously treated relapsed malignancies was performed. An initial peripheral stem cell apheresis collection was conducted during steady-state hematopoiesis for each patient to provide baseline data. rhEpo, 200 U/kg/day, was administered subcutaneously until the last apheresis procedure was completed. Immediately after the fourth daily dose of Epo, apheresis procedures were resumed and continued beyond five collections, when necessary, to accrue a total of 6.5 x 10(8) mononuclear cells (MNCs)/kg. Eight female and four male patients (median age = 44 years) were evaluated. Five to 14 (median = 8) apheresis procedures were performed for each patient. Toxicity attributable to Epo administration was negligible. Mobilization effects, as determined by an increase in the number of colony-forming units granulocyte/macrophage (CFU-GM) and burst-forming units-erythroid (BFU-E) in the apheresis products after Epo administration, were observed in all patients. Nine patients received high-dose chemotherapy and Epo-mobilized peripheral stem cell transplantation (PSCT). Beginning the day of the transplant, GM-CSF was administered until neutrophil recovery was satisfactory. The median time to recover 0.5 x 10(9)/L granulocytes was 16 days after PSCT. Epo appears to have mobilization properties. Further studies are needed to determine the clinical usefulness of Epo as a mobilizing cytokine. The addition of Epo to other mobilizing cytokines may provide increased effectiveness without adding toxicity. 相似文献
160.