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91.
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Sylvia Baumann Kurer Burkhardt Seifert Beat Michel† Regula Ruegg Jörg Fehr 《British journal of haematology》1995,91(4):820-826
Summary. We prospectively studied 45 anaemic patients (3 7 women, 8 men) with chronic inflammatory rheumatic diseases. The combination of serum ferritin and CRP (as well as ESR) in its predictive capacity for bone marrow iron stores was examined. The relationship between other iron-related measurements (transferrin, transferrin saturation, soluble transferrin receptor, erythrocyte porphyrins and percentage of hypochromic/microcytic erythrocytes) and bone marrow iron stores was also investigated. Stainable bone marrow iron was taken as the most suitable standard to separate iron-deficient from iron-replete patients. 14 patients (31%) were lacking bone marrow iron. Regression analysis showed a good correlation between ferritin and bone marrow iron (adjusted R 2 =0.721, P<00001). The combination of ferritin and CRP (ESR) did not improve the predictive power for bone marrow iron (adjusted R 2 =0.715) in this cohort of patients with low systemic inflammatory activity. With respect to the bone marrow iron content the best predictive cut-off value of ferritin was 30μg/l (86% sensitivity, 90% specificity). The other iron-related parameters both individually and when combined were less powerful in predicting bone marrow iron than ferritin alone. Only zinc bound erythrocyte protoporphyrin in combination with ferritin slightly improved prediction (adjusted R 2 =0.731). A cut-off point of 11% hypochromic erythrocytes reached a high specificity (90%), but was less sensitive (77%). 相似文献
94.
Lymph node and bone marrow biopsies of 226 patients with malignant lymphomas were available for evaluation and comparison. 120 of the 226 lymphoma patients had classifiable infiltration in both lymph node and bone marrow and these were used for comparison. Congruence in the histologic subtypes in lymph node and bone marrow was found in 91 patients (76%). The majority of the 29 cases with divergent histologies showed ML of low grade malignancy in the bone marrow even with long time intervals between the two biopsies. The most notable in this group were seven cases who had ML centroblastic/centrocytic in the lymph node biopsy and ML immunocytic in the bone marrow, although none had a serum M-component. 65 of the 106 patients excluded from comparison had involvement in only one organ, the others had unclassifiable or equivocal histologies in either lymph node or bone marrow or in both. The findings are discussed with respect to the histologic behaviour of the lymphomas. The results show that comparison between lymph node and bone marrow findings in patients with ML is feasible and clinically relevant. 相似文献
95.
Domenico G. Della Rocca MD Michele Magnocavallo MD Veronica N. Natale MPH Carola Gianni MD PhD Sanghamitra Mohanty MD Chintan Trivedi MD MPH Carlo Lavalle MD Giovanni B. Forleo MD PhD Nicola Tarantino MD Jorge Romero MD Xiadong Zhang MD Mohamed Bassiouny MD Amin Al-Ahmad MD David J. Burkhardt MD Joseph G. Gallinghouse MD Javier E. Sanchez MD Rodney P. Horton MD Luigi Di Biase MD PhD Andrea Natale MD 《Journal of cardiovascular electrophysiology》2021,32(9):2441-2450
96.
97.
Cutaneous response to recombinant interleukin 2 in human immunodeficiency virus 1-seropositive individuals 总被引:3,自引:0,他引:3 下载免费PDF全文
M J McElrath G Kaplan R A Burkhardt Z A Cohn 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(15):5783-5787
We report that 11 human immunodeficiency virus 1 (HIV-1)-seropositive patients, including three AIDS patients, were able to generate a cellular immune response to the intradermal injection of low doses (2-10 micrograms) of recombinant interleukin 2 (rIL-2). A dose-dependent zone of induration appeared at the site of injection, peaked at 24 hr, and was accompanied by the local accumulation of T cells, monocytes, and Langerhans cells. Despite the reductions in the CD4+ T-cell counts in the peripheral blood of most patients, CD4+ T-cells could still be mobilized with rIL-2 injections into the skin. The total number of immigrant cells was equivalent to those in HIV-1-seronegative patients, although the CD4+/CD8+ ratio of the dermal population was reduced. In response to rIL-2, major histocompatibility complex (MHC) class II antigen was expressed on the surface of keratinocytes, Langerhans cells, lymphocytes, and macrophages. In addition, the gamma interferon (IFN-gamma)-induced protein IP-10 rapidly appeared in dermal inflammatory cells and keratinocytes. A majority of HIV-1-seropositive patients demonstrated low or absent responses to common skin-test antigens. Those with positive zones of induration were often defective in the cellular expression of the IFN-gamma-induced MHC class II antigen. The simultaneous administration of rIL-2 and soluble antigen at widely separated cutaneous sites led to an enhancement of skin-test antigen reactivity in seropositive patients. The results suggest that local administration of rIL-2 to seropositive patients may act systemically, stimulating cellular immunity to recall antigens, and thus may be of potential benefit in the defense against opportunistic pathogens encountered in HIV-1 infection. 相似文献
98.
E. F. Lampeter H. Kolb I. Seifert D. Lohmann J. W. Heise J. Bertrams M. R. Christie V. Kolb-Bachofen 《Diabetologia》1994,37(5):471-475
Summary The hypothesis was tested that islet autoimmunity is induced by ongoing islet cell destruction in subjects with susceptibility
genes HLA-DR 3 and/or DR 4. Sixty-one patients with confirmed chronic pancreatitis were analysed, 30 of whom expressed HLA-DR
3 and/or DR 4. Electron microscopy studies in 10 patients showed that the inflammatory process also affected islets, as recognisable
from islet cell lysis, intrainsular fibrosis and immune cell infiltrates. None of the sera tested contained any of three markers
of islet autoimmunity, ICA, IAA or GAD antibodies. A correlation was seen between the loss of exocrine function, as determined
by the ALTAB-test, and of beta-cell function, as determined by the C-peptide response to i. v. glucagon. However, there was
no preferential loss of beta-cell function in patients with HLA-DR 3 and/or DR 4. We conclude that islet cell destruction
occurs during chronic pancreatitis, but does not trigger islet autoimmunity, even in the presence of HLA-DR 3 and/or DR 4.
[Diabetologia (1994) 37: 471–475]
Received: 18 August 1993 and in revised form: 17 November 1993 相似文献
99.
The PCBP1 gene encoding poly(rc) binding protein i is recurrently mutated in Burkitt lymphoma 下载免费PDF全文
Rabea Wagener Sietse M. Aukema Matthias Schlesner Andrea Haake Birgit Burkhardt Alexander Claviez Hans G. Drexler Michael Hummel Markus Kreuz Markus Loeffler Maciej Rosolowski Cristina Lpez Peter Mller Julia Richter Marius Rohde Matthew J. Betts Robert B. Russell Stephan H. Bernhart Steve Hoffmann Philip Rosenstiel Markus Schilhabel Monika Szczepanowski Lorenz Trümper Wolfram Klapper Reiner Siebert 《Genes, chromosomes & cancer》2015,54(9):555-564
The genetic hallmark of Burkitt lymphoma is the translocation t(8;14)(q24;q32), or one of its light chain variants, resulting in IG‐MYC juxtaposition. However, these translocations alone are insufficient to drive lymphomagenesis, which requires additional genetic changes for malignant transformation. Recent studies of Burkitt lymphoma using next generation sequencing approaches have identified various recurrently mutated genes including ID3, TCF3, CCND3, and TP53. Here, by using similar approaches, we show that PCBP1 is a recurrently mutated gene in Burkitt lymphoma. By whole‐genome sequencing, we identified somatic mutations in PCBP1 in 3/17 (18%) Burkitt lymphomas. We confirmed the recurrence of PCBP1 mutations by Sanger sequencing in an independent validation cohort, finding mutations in 3/28 (11%) Burkitt lymphomas and in 6/16 (38%) Burkitt lymphoma cell lines. PCBP1 is an intron‐less gene encoding the 356 amino acid poly(rC) binding protein 1, which contains three K‐Homology (KH) domains and two nuclear localization signals. The mutations predominantly (10/12, 83%) affect the KH III domain, either by complete domain loss or amino acid changes. Thus, these changes are predicted to alter the various functions of PCBP1, including nuclear trafficking and pre‐mRNA splicing. Remarkably, all six primary Burkitt lymphomas with a PCBP1 mutation expressed MUM1/IRF4, which is otherwise detected in around 20–40% of Burkitt lymphomas. We conclude that PCBP1 mutations are recurrent in Burkitt lymphomas and might contribute, in cooperation with other mutations, to its pathogenesis. © 2015 Wiley Periodicals, Inc. 相似文献
100.
Effects on human heart valve immunogenicity in vitro by high concentration cryoprotectant treatment 下载免费PDF全文
Benjamin A. Högerle Maria Schneider Katrin Sudrow Naima Souidi Meaghan Stolk Isabella Werner Anna Biermann Kelvin G.M. Brockbank Ulrich A. Stock Martina Seifert 《Journal of tissue engineering and regenerative medicine》2018,12(2):e1046-e1055
It has been shown previously that cryopreservation, using an ice‐free cryopreservation method with the cryoprotectant formulation VS83, beneficially modulated immune reactions in vivo and in vitro when compared with conventionally frozen tissues. In this study, we assessed the impact of a VS83 post‐treatment of previously conventionally frozen human tissue on responses of human immune cells in vitro. Tissue punches of treated and non‐treated (control) aortic heart valve tissue (leaflets and associated aortic root) were co‐cultured for 7 days with peripheral blood mononuclear cells or enriched CD14+ monocytes. Effects on cellular activation markers, cytokine secretion and immune cell proliferation were analysed by flow cytometry. Flow cytometry studies showed that VS83 treatment of aortic root tissue promoted activation and differentiation of CD14+ monocytes, inducing both up‐regulation of CD16 and down‐regulation of CD14. Significantly enhanced expression levels for the C‐C chemokine receptor (CCR)7 and the human leukocyte antigen (HLA)‐DR on monocytes co‐cultured with VS83‐treated aortic root tissue were measured, while the interleukin (IL)‐6 and monocyte chemoattractant protein (MCP)‐1 release was suppressed. However, the levels of interferon (IFN)γ and tumour necrosis factor (TNF)α remained undetectable, indicating that complete activation into pro‐inflammatory macrophages did not occur. Similar, but non‐significant, changes occurred with VS83‐treated leaflets. Additionally, in co‐cultures with T cells, proliferation and cytokine secretion responses were minimal. In conclusion, post‐treatment of conventionally cryopreserved human heart valve tissue with the VS83 formulation induces changes in the activation and differentiation characteristics of human monocytes, and thereby may influence long‐term performance following implantation. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献