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61.
The effect of azathioprine on the kinetics of peripheral blood monocytes and peritoneal macrophages was studied in normal mice and in mice in which an inflammatory reaction was provoked. Two dosage levels were used: a high dose of 200mg/kg which is the maximum tolerated daily dose in mice, and low dose of 3 mg/kg which is about equivalent to a nontoxic, immunosuppressive, anti-inflammatory dose in man. The number of peripheral blood monocytes decreases gradually during azathioprine treatment of normal mice, the extent and duration being dependent on the dose and duration of administered over a period of 9 days gives an almost complete reduction, and a low dose (3 mg/kg) given for the same period results in a reduction of about 50%. This effect seems to be reversible, because when treatment is stopped the number of monocytes starts to increase 24-48 hr later. The number of peritoneal macrophages is only affected when a high dose (200 mg/kg) is given over a long period; a low dose has virtually no effect. In mice in which an inflammatory reaction was prevoked in the peritoneal cavity, the normally occurring increase in the numbers of both peripheral blood monocytes and peritoneal macrophages was suppressed, the extent being dependent on the dose of azathioprine administered. Labeling studies with 3H-thymidine indicated that the reduction of peripheral blood monocytes and peritoneal macrophages in the inflammatory exudate is due to a diminished monocyte production. 相似文献
62.
de Haas M; Kerst JM; van der Schoot CE; Calafat J; Hack CE; Nuijens JH; Roos D; van Oers RH; von dem Borne AE 《Blood》1994,84(11):3885-3894
In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 micrograms of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, Fc gamma RIII was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor alpha 1- antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF--induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo. 相似文献
63.
Abstract: Point mutation of the p53 tumor suppressor gene appears to be an important event in tumor development and progression, and overexpression of the p53 gene product has been widely studied in a variety of neoplasms. Some point mutations of the p53 gene lead to an increase in half-life in the gene product, which accumulates in the nucleus and can be detected by immunohistochemical means. We studied overexpression of p53 protein in specimens from 12 patients with adenocarcinoma of the gallbladder, two gallbladders with epithelial dysplasia without carcinoma, eight carcinomas of the common bile duct, 13 hilar cholangiocarcinomas, and six peripheral cholangiocarcinomas. The monoclonal antibody Ab-2 (Oncogene Science) was used in conjunction with citrate microwave antigen retrieval. Nuclear staining was scored as positive (graded 1 to 3, depending on number of positive nuclei) or negative. Overexpression of p53 protein was present in 7/12 (58%) gallbladder carcinomas, and was seen more often in moderately or poorly differentiated tumors. Intramucosal carcinoma adjacent to invasive carcinoma was positive in three cases, although fewer cells stained than in the carcinoma. Two cases of low-grade dysplasia not associated with carcinoma were negative. Expression of p53 was not an independent prognostic factor when survival was related to grade and stage of tumor. Three of eight (38%) common bile duct carcinomas and 5/13 (38%) hilar cholangiocarcinomas were positive for p53. Slightly fewer (2/6, 33%) peripheral cholangiocarcinomas were positive. No difference in survival relative to p53 expression was demonstrated. 相似文献
64.
Katherine Smith Carmen Washington Jennifer Brown Alison Vadnais Laura Kroart Jacqueline Ferguson Joanna Cohen 《JMIR Public Health and Surveillance》2015,1(2)
Background
Tobacco remains the world’s leading preventable cause of death, with the majority of tobacco-caused deaths occurring in low- and middle-income countries. The first global health treaty, the Framework Convention on Tobacco Control (FCTC), outlines a set of policy initiatives that have been demonstrated as effective in reducing tobacco use. Article 11 of the FCTC focuses on using the tobacco package to communicate tobacco-caused harms; it also seeks to restrict the delivery of misleading information about the product on the pack.Objective
The objective of this study was to establish a surveillance system for tobacco packs in the 14 low- and middle-income countries with the greatest number of smokers. The Tobacco Pack Surveillance System (TPackSS) monitors whether required health warnings on tobacco packages are being implemented as intended, and identifies pack designs and appeals that might violate or detract from the communication of harm-related information and undermine the impact of a country’s tobacco packaging laws. The protocol outlined is intended to be applicable or adaptable for surveillance efforts in other countries.Methods
Tobacco packs were collected in 14 countries during 2013. The intention was, to the extent possible, to construct a census of “unique” pack presentations available for purchase in each country. The TPackSS team partnered with in-country field staff to implement a standardized protocol for acquiring packs from 36 diverse neighborhoods across three cities in each country. At the time of purchase, data on price and place of acquisition of each pack was recorded. The field staff, according to a standardized protocol, then photographed packs before they were shipped to the United States for coding and archiving.Results
Each pack was coded for compliance with the country-specific health warning label laws, as well as for key design features of the pack and appeals of the branding elements. The coding protocols were developed based upon prior research, expert opinion, and communication theories. Each pack was coded by two independent coders, with consistency of personnel across the project. We routinely measured intercoder reliability, and only retained variables for which a good level of reliability was achieved. Variables where reliability was too low were not included in final analyses, and any inconsistencies in coding were resolved on a daily basis.Conclusions
Across the 14 countries, the TPackSS team collected 3307 tobacco packs. We have established a publicly accessible, Internet archive of these packs that is intended for use by the tobacco control policy advocacy and research community. 相似文献65.
Alain P. Gobert Olivier Boutaud Mohammad Asim Irene A. Zagol-Ikapitte Alberto G. Delgado Yvonne L. Latour Jordan L. Finley Kshipra Singh Thomas G. Verriere Margaret M. Allaman Daniel P. Barry Kara M. McNamara Johanna C. Sierra Venkataraman Amarnath Mohammed N. Tantawy Diane Bimczok M. Blanca Piazuelo M. Kay Washington Keith T. Wilson 《Gastroenterology》2021,160(4):1256-1268.e9
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66.
67.
A potent small molecule inhibits polyglutamine aggregation in Huntington's disease neurons and suppresses neurodegeneration in vivo
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Zhang X Smith DL Meriin AB Engemann S Russel DE Roark M Washington SL Maxwell MM Marsh JL Thompson LM Wanker EE Young AB Housman DE Bates GP Sherman MY Kazantsev AG 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(3):892-897
Polyglutamine (polyQ) disorders, including Huntington's disease (HD), are caused by expansion of polyQ-encoding repeats within otherwise unrelated gene products. In polyQ diseases, the pathology and death of affected neurons are associated with the accumulation of mutant proteins in insoluble aggregates. Several studies implicate polyQ-dependent aggregation as a cause of neurodegeneration in HD, suggesting that inhibition of neuronal polyQ aggregation may be therapeutic in HD patients. We have used a yeast-based high-throughput screening assay to identify small-molecule inhibitors of polyQ aggregation. We validated the effects of four hit compounds in mammalian cell-based models of HD, optimized compound structures for potency, and then tested them in vitro in cultured brain slices from HD transgenic mice. These efforts identified a potent compound (IC50=10 nM) with long-term inhibitory effects on polyQ aggregation in HD neurons. Testing of this compound in a Drosophila HD model showed that it suppresses neurodegeneration in vivo, strongly suggesting an essential role for polyQ aggregation in HD pathology. The aggregation inhibitors identified in this screen represent four primary chemical scaffolds and are strong lead compounds for the development of therapeutics for human polyQ diseases. 相似文献
68.
Fc gamma receptor II (CD32) on malignant B cells influences modulation induced by anti-CD19 monoclonal antibody 总被引:1,自引:1,他引:1
Vervoordeldonk SF; Merle PA; van Leeuwen EF; van der Schoot CE; von dem Borne AE; Slaper-Cortenbach IC 《Blood》1994,83(6):1632-1639
Antigenic modulation is one of many factors determining the effectiveness of monoclonal antibody (MoAb)-mediated therapy. To select the isotype of a CD19 MoAb most suitable for radioimmunotherapy of patients with B-cell malignancies, we studied the influence of MoAb isotype on modulation, after binding of the MoAb to different cell-line cells. The CD19-IgG1 MoAb was found to induce modulation of CD19 antigens on Daudi cell line cells more rapidly than did its IgG2a switch variant. We provide evidence that this difference in modulation rate is caused by the expression of Fc gamma receptor II (Fc gamma RII) on these cells. Experiments aimed at elucidating the mechanism of Fc gamma RII involvement in modulation induction by CD19-IgG1 showed that Fc gamma RII did not comodulate with CD19 MoAbs. However, cocrosslinking of CD19 and Fc gamma RII with CD19-IgG1 MoAb resulted in enhanced calcium mobilization in Daudi cells. This increased signal induction accompanies the enhanced capping and subsequent modulation of CD19 antigens. Because Fc gamma RII is expressed in varying densities on malignant B cells in all differentiation stages, our results have implications for the MoAb isotype most suitable for use in MoAb-based therapy of patients with B-cell malignancies. 相似文献
69.
Histamine reduces boron neutron capture therapy‐induced mucositis in an oral precancer model
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70.
Seth C Kalichman Chauncey Cherry Moira O Kalichman Christopher Washington Tamar Grebler Cindy Merely Brandi Welles Jennifer Pellowski Christopher Kegler 《Journal of the International AIDS Society》2015,18(1)