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11.
The lifespan of antigen-bearing dendritic cells (DCs) is determined by signals from pathogens and T cells. These signals regulate DC survival by modulating expression of Bcl-2 family proteins. Toll-like receptors and T cell costimulatory molecules both trigger a DC survival pathway that is dependent on Bcl-x(L). However, Toll-like receptors uniquely increase expression of Bim and trigger cell death by a pathway that is blocked by Bcl-2. This pathway serves as a molecular 'timer' that sets the lifespan of DCs and regulates the magnitude of T cell responses in vivo. Thus, signals derived from the innate and acquired immune systems control DC lifespan and immunogenicity by distinct molecular mechanisms. 相似文献
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Deepika D'Cunha Burkardt Anna Zachariou Chey Loveday Clare L. Allen David J. Amor Anna Ardissone Siddharth Banka Alexia Bourgois Christine Coubes Cheryl Cytrynbaum Laurence Faivre Gerard Marion Rachel Horton Dieter Kotzot Guillermo Lay‐Son Melissa Lees Karen Low Ho‐Ming Luk Paul Mark Allyn McConkie‐Rosell Marie McDonald John Pappas Christophe Phillipe Deborah Shears Brian Skotko Fiona Stewart Helen Stewart I Karen. Temple Frederic T. Mau‐Them Ricardo A. Verdugo Rosanna Weksberg Yuri A. Zarate John M. Graham Katrina Tatton‐Brown 《American journal of medical genetics. Part A》2019,179(10):2049-2055
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Use of the lectin from Amaranthus caudatus as a histochemical probe of proliferating colonic epithelial cells 总被引:2,自引:0,他引:2
C R Boland Y F Chen S J Rinderle J H Resau G D Luk H T Lynch I J Goldstein 《Cancer research》1991,51(2):657-665
A newly isolated lectin, Amaranthus caudatus agglutinin (also called amaranthin or ACA), which binds to the Thomsen-Friedenreich antigen (T-antigen) and its sialylated variants, was used as a histochemical probe for proliferating cells in sections of human colonic tissues. Binding inhibition studies revealed that ACA binds to different sites on histological sections when compared to peanut agglutinin, which also recognizes the T-antigen. ACA bound selectively to the cells at the base of the colonic crypt [46 +/- 4% (SEM) of glands] which is the zone of proliferation in this tissue and preferentially labeled cytoplasmic and apical membrane glycoconjugates. Only 7 +/- 2% of the upper portions of the colonic crypts were labeled (P less than 0.001 compared to the base), and this was largely a result of extensive labeling in 2 of 23 samples studies. A marked increase in histochemical labeling by ACA was seen in adenomatous polyps and adenocarcinomas of the colon, in which 82 +/- 7 and 97 +/- 2% of the glandular units were labeled, respectively. Transitional mucosa and connective tissue adjacent to cancers were also labeled by ACA. Neuraminidase studies indicated that removal of sialic acid residues enhanced binding by peanut agglutinin, but not ACA, to glycoconjugates in cancer specimens. Specimens of colonic tissue from patients with familial adenomatous polyposis (FAP) were examined with ACA; 83 +/- 7% of adenomatous glands and 60 +/- 7% of glands in flat, normal-appearing tissue were labeled. Colonic tissues from persons at 50% risk for hereditary nonpolyposis colorectal cancer (HNPCC), FAP, and normal colons were studied and given "weighted average" labelling scores that ranged from 0-400 to accommodate variable intensity and distribution of labeling. Normal colons had a weighted average score of 65 +/- 33; FAP tissues had a score of 224 +/- 76 (P less than 0.001 compared to normal colon) and HNPCC tissues had a score of 74 +/- 70 (P less than 0.05 compared to normal colon). A group of five HNPCC cases had scores of 203 +/- 43 (P less than 0.001 compared to normal colon). ACA labels glycoconjugates in the proliferative region of normal human colonic epithelium and neoplastic lesions of the colon. The results of FAP and HNPCC tissues suggest that it may be useful for identifying foci of abnormal proliferation in familial colorectal cancer syndromes. 相似文献
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Adriana Luk Andrew Lee Eric Ahn Gursharan S Soor Heather J Ross Jagdish Butany 《The Canadian journal of cardiology》2010,26(7):e273-e275
Cardiac transplantation is indicated for patients with end-stage cardiomyopathy secondary to cardiac sarcoidosis. Although rare, recurrent disease has been reported in two cases. The current report presents a case of recurrent cardiac sarcoidosis in a patient 45 months postorthotopic heart transplantation and 40 months following reactivation of latent Mycobacterium tuberculosis infection. The patient was the first to have recurrent disease following an infection that has been proposed to be involved in its pathogenesis. The patient’s interval between transplant and recurrence is the longest reported to date. 相似文献
18.
Nobel Yael R. Su Steven H. Anderson Michaela R. Luk Lyndon Small-Saunders Jennifer L. Reyes-Soffer Gissette Gallagher Dympna Freedberg Daniel E. 《Digestive diseases and sciences》2022,67(9):4484-4491
Digestive Diseases and Sciences - Patients with SARS-CoV-2 who present with gastrointestinal symptoms have a milder clinical course than those who do not. Risk factors for severe COVID-19 disease... 相似文献
19.
G. L. Lukács I. Zs.-Nagy Gy. Lustyik Gy. Balázs 《Journal of cancer research and clinical oncology》1983,105(3):280-284
Summary Parallel studies were performed using microfluorimetric DNA determination and X-ray microanalysis on the same thyroid biopsy material to compare the intranuclear DNA and monovalent electrolyte contents (Na+, K+, Cl–). Samples were taken from apparently healthy, adenomatous, and cancerous parts of human thyroid glands removed surgically. The time interval was less than 1 min. The tissues were classified by the pathologist into four main classes: 1) Normal thyroid tissue; 2) benign adenomas; 3) differentiated (follicular and papillary) carcinomas; and 4) anaplastic cancers. The results revealed that the level of aneuploidization showed an increase parallel with the malignancy of the studied tumor. At the same time, a similar tendency was found in the average values of the intranuclear Na+:K+ ratios. The results obtained in this way confirm the possibility that the electric properties of the cell membrane, that is the sustained membrane depolarization, may have a role in the regulation of DNA synthesis and in mitogenesis. These results may offer new diagnostic and/or therapeutic possibilities. 相似文献
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Macdonald Dianne Luk Gigi Quintin Eve-Marie 《Journal of autism and developmental disorders》2021,51(5):1613-1613
Journal of Autism and Developmental Disorders - The original version of this article unfortunately contained a mistake in Table 6. The column headings was repeated in the first column along with... 相似文献