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81.
Fas ligand (FasL) exists in transmembrane and soluble forms and induces apoptosis on cross-linking with the Fas receptor. We evaluated the biological significance of FasL and Fas in 61 tumor tissues and 9 cell lines of the Ewing's sarcoma family of tumors (ESFT). FasL was present in 62.5% and Fas in 79.4% of primary ESFT. Metastatic tumors had higher expression of FasL (95%), suggesting association with a metastatic phenotype. FasL was detected in the cytoplasm and membrane of ESFT cells by immunofluorescence. Western blotting revealed transmembrane and soluble FasL in cytosolic extracts and soluble FasL in conditioned media. Both transmembrane and soluble FasL induced apoptosis of Fas-sensitive Jurkat cells in co-culture experiments with ESFT cells or their media. Treatment with phenanthroline and the synthetic metalloproteinase inhibitor BB-3103 reduced the levels of soluble FasL in the media, suggesting that in ESFT, FasL is processed by a metalloproteinase and released in the extracellular milieu. The released soluble FasL may serve to attack cells of the immune system and/or interfere with the binding of transmembrane FasL with Fas, and results in down-regulation of transmembrane FasL. Synthetic metalloproteinase inhibitors may modify the ratio of transmembrane to soluble FasL.  相似文献   
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Columns of Greek Temples under seismic loading: Columns of ancient Greek Temples consist of accurately dressed individual blocks in total absence on binding mortars. The seismic response of such multi‐drum structures is completely different than the corresponding one of modern continuous structures. Their stability is governed by independent sliding and rocking of drums, which creates an external energy absorption mechanism. This paper presents numerical studies on the dynamic behaviour of ancient columns which exhibits a highly non‐linear response. Alternative modeling methods are used and calibrated to experimental results. It is concluded that ancient columns may be less vulnerable to seismic events compared to modern structures. The perfection of the form unified esthetical, architectural and structural requirements.  相似文献   
84.
Various finite elements based on mixed formulations have been proposed for the solution of boundary value problems involving strain-gradient models. The relevant literature, however, does not provide details on some important theoretical aspects of these elements. In this work, we first present the existing elements within a novel, single mathematical framework, identifying some theoretical issues common to all of them that affect their robustness and numerical efficiency. We then proceed to develop a new family of mixed elements that addresses these issues while being simpler and computationally cheaper. The behavior of the new elements is further demonstrated through two numerical examples.  相似文献   
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The effectiveness of coronavirus disease 2019 (COVID-19) vaccination strategies is affected by several factors, including the genetic background of the host. In our study, we evaluated the contribution of the functional polymorphism rs1883832 affecting the Kozak sequence of the TNFSF5 gene (c.-1C>T), encoding CD40, to humoral immune responses after vaccination with the spike protein of SARS-CoV-2. The rs1883832 polymorphism was analyzed by PCR-RFLP in 476 individuals (male/female: 216/260, median age: 55.0 years, range: 20–105) of whom 342 received the BNT162b2 mRNA vaccine and 134 received the adenovirus-based vector vaccines (67 on ChAdOx1-nCoV-19 vaccine, 67 on Ad.26.COV2.S vaccine). The IgG and IgA responses were evaluated with chemiluminescent microparticle and ELISA assays on days 21, 42, and 90 after the first dose. The T allele of the rs1883832 polymorphism (allele frequency: 32.8%) was significantly associated with lower IgA levels and represented, as revealed by multivariable analysis, an independent risk factor for reduced anti-spike protein IgA levels on days 42 and 90 following BNT162b2 mRNA vaccination. Similar to serum anti-spike IgA levels, a trend of lower anti-spike IgA concentrations in saliva was found in individuals with the T allele of rs1883832. Finally, the intensity of IgA and IgG responses on day 42 significantly affected the prevalence of COVID-19 after vaccination. The rs1883832 polymorphism may be used as a molecular predictor of the intensity of anti-spike IgA responses after BNT162b2 mRNA vaccination.  相似文献   
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Immunosenescence encompasses a spectrum of lymphocyte phenotypic alterations. The aim of the study was to evaluate immunosenescent effect of two different forms of chronic inflammation, Systemic Lupus Erythematosous (SLE), a systemic autoimmune disease, and End-Stage Kidney Disease (ESKD), a chronic inflammatory disorder. Certain lymphocyte surface molecules, including CD31, CD45RA, CCR7, CD28, CD57, for T, and IgD, CD27 for B lymphocytes, were analyzed by flow cytometry in 30 SLE and 53 ESKD patients on hemodialysis (HD), and results were compared to 31 healthy controls (HC) of similar age, gender, and nationality. Significant Lymphopenia was evident in both SLE and ESKD-HD patients, compared to HC, affecting B cells 75.4 (14.4–520.8), 97 (32–341), and 214 (84–576) cells/μL, respectively, p < 0.0001, and CD4 cells 651.2 (71.1–1478.2), 713 (234–1509), and 986 (344–1591) cells/μL, respectively, p < 0.0001. The allocation of B cell subpopulations was remarkably different between SLE and ESKD-HD patients. SLE showed a clear shift to senescence (CD19IgD-CD27−) cells, compared to ESKD-HD and HC, 11.75 (10)% vs. 8 (6) vs. 8.1 (10), respectively. Regarding T lymphocytes, Central Memory CD8 cells predominated in both SLE and ESKD-HD patients compared to HC, 53 (50)%, 52 (63), and 24 (64)%, respectively, while ESKD-HD but not SLE patients also had increased expression of CD4CD28− and CD8CD28− cells. In conclusion, both diseases are followed by significant lymphopenia; however, the senescent phenomenon affects the B lymphocyte compartment in SLE patients and T lymphocytes in ESKD-HD patients.  相似文献   
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A series of substituted indolo[2,1-a]isoquinolines and indolo[1,2-a]benzoxazines have been prepared, as melatonin analogues, to investigate the nature of the binding site of the melatonin receptor. Agonist and antagonist potency of all the analogues was measured using the [35S]GTPγS binding assay protocol. The binding affinity of the analogues were measured by competition binding studies against the human MT1 (hMT1) and MT2 (hMT2) receptors stably transfected in Chinese Hamster Ovarian (CHO) cells, using 2-[125I]-iodomelatonin, as a ligand. N-Acetyl 2-(10-methoxy-5,6-dihydroindolo[2,1-a]isoquinolin-12-yl)propyl-1-amine (12 a) binds strongly to both the hMT1 and hMT2 receptors, and shows a preference for the hMT2, as does its propanamido counterpart 12 b . The introduction of two methyl groups into their side chain, analogues 15 a and 1 5 b , leads to antagonism, in the case of the former, and drastically diminishes its hMT1 binding; an analogous profile is seen for 15 b , which, however, is a partial agonist. Introduction of chlorine or methoxy groups into ring 4 gives compounds, that are weakly binding, with a preference for MT2. Substitution of oxygen for carbon at position 5 gives the indolo[1,2-c]benzoxazines 33 , 36 a and b , that bind strongly to the human receptors, 33 , 36 b being potent agonists at the melatonin receptors, but do not discriminate between hMT1 and hMT2.  相似文献   
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