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In sarcoidosis, host genetic factors are discussed as contributing to disease susceptibility and course. Since tumor necrosis factor (TNF)-α is a central mediator of granuloma formation and since elevated TNF-α levels are found during active phases of sarcoidosis, genetic polymorphisms correlating with influences on TNF-α levels are of special interest. The complete sequencing of the MHC region and the increase in the number of identified gene polymorphisms in this locus associated with TNF-α production offer the opportunity of detecting new genes associated with sarcoidosis and perhaps of defining disease-associated haplotypes that bear the potential of serving as predictive markers for this disease.  相似文献   
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An archeological wooden painted coffin was excavated in Tety tomb from Saqqara excavation. It belonged to the Ministry of Antiquities. This coffin was discovered in a bad state of conservation with many destroyed big and small pieces in Saqqara stores. Analyses and investigation study were performed on the ground layer of the coffin by X-ray diffraction (XRD), Energy dispersive X ray analysis (EDX) equipped with environmental scanning electron microscopy (ESEM) and Fourier transform infrared spectroscopy (FTIR). Results confirmed that the degradation factors affecting the wooden painted coffin are essentially attributed to direct effects of microbial phenomena, which have lead to many deterioration forms as: macro- and microcracks, hydrated salts, flaking, coloration, scaling and defoliation microbiological spots. Nine deteriorating fungal species were isolated from the painted and ground layers of the tested coffin. Fusarium moniliforme followed by Aspergillus flavus able to significantly solublize calcium salts as major components of the ground layer of archeological wooden coffin. Effect of ozone and Gamma sterilization on growth; lipid, tryptophan oxidation and protein, nucleic acid leakage in the most dominant toxigenic deteriorated fungal species were detected. No mycelial growth was observed at 4 ppm of ozone at all exposure times. As Gamma radiation dose increased over 250 Gy, the growth parameter gradually decreased to reach the lethal dose at 2000 Gy. The production of mycotoxins by the tested toxigenic fungi was completely disappeared under the exposure to 3 ppm and 90 min to ozone.  相似文献   
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Histone H2B ubiquitination is a dynamic modification that promotes methylation of histone H3K79 and H3K4. This crosstalk is important for the DNA damage response and has been implicated in cancer. Here, we show that in engineered yeast strains, ubiquitins tethered to every nucleosome promote H3K79 and H3K4 methylation from a proximal as well as a more distal site, but only if in a correct orientation. This plasticity indicates that the exact location of the attachment site, the native ubiquitin-lysine linkage and ubiquitination cycles are not critical for trans-histone crosstalk in vivo. The flexibility in crosstalk also indicates that other ubiquitination events may promote H3 methylation.  相似文献   
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Lethally irradiated mice were infused with syngeneic, H-2 allogeneic, parental strain, or H-2 heterozygous bone marrow cells. They were injected daily with rabbit anti-mouse interferons (IFN)-alpha/beta or gamma or with IFN-alpha/beta. The growth of donor-derived cells was judged 5 days later by measuring splenic incorporation of 5-iodo-2'-deoxyuridine-125I into DNA. Antibodies to IFN-alpha/beta, but not to IFN-gamma, weakened genetic (both hybrid and allogeneic) resistance to marrow cell grafts. IFN-alpha/beta stimulated hybrid and allogeneic resistance, the latter even in genetically "poor responder" mice. Mice pretreated with silica, which weakens genetic resistance, were stimulated by IFN-alpha/beta to resist incompatible marrow cell grafts; however, IFN-alpha/beta failed to reverse the effects of antiasialo GM1 serum on marrow graft rejection. IFN-alpha/beta did not inhibit the growth of syngeneic marrow cells and did not stimulate resistance to H-2 heterozygous bone marrow cells. We propose that genetic resistance occurs in two discrete steps. In the first step, hemopoietic histocompatibility (Hh) antigens are recognized by one host cell type, and this recognition leads to IFN-alpha/beta secretion by a silica-sensitive cell. In the second step, asialo GM1-positive natural killer cells stimulated by IFN-alpha/beta recognize Hh antigens on marrow stem cells and cause rejection. The defects in resistance observed in genetically poor responder mice and in mice treated with silica appear to involve the first step in recognition. The lack of rejection of H-2 heterozygous (Hh-) marrow cells by parental strain mice injected with IFN-alpha/beta indicated that specific Hh recognition is critical in the second step of genetic resistance.  相似文献   
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