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1.
Yasuo Kobayashi Robert J. Forster Mary Alice Hefford Ronald M. Teather Masaaki Wakita Kunio Ohmiya Sadao Hoshino 《FEMS microbiology letters》1995,130(2-3):137-143
Abstract A small cryptic plasmid, pRJF2, from Butyrivibrio fibrisolvens strain OB157 was isolated and sequenced. The plasmid is similar in organisation to the previously sequenced Butyrivibrio plasmid, pRJF1, with two open reading frames, ORF1 and ORF2, flanking a region tentatively identified as the replication origin, and a region of unknown function defined by terminal 79 bp invert repeats. The sequences of ORF1, ORF2, and the presumptive replication origin are highly conserved. The sequence between the 79 bp invert repeats is not, and is therefore presumed to be of lesser functional significance, although the 5' and 3' termini are still highly conserved. The functional importance for plasmid replication of these regions was tested by constructing potential shuttle vectors, each lacking one or more of the regions of interest. When the region between the invert repeats was deleted and replaced by the erythromycin resistance gene from pAM β1 together with pUC18, to produce the 7.9 kb chimaeric plasmid pYK4, the construct was successfully transformed into E. coli and B. fibrisolvens by electroporation, and was stably maintained in both hosts. Both ORF1 and ORF2 were required for successful transformation of B. fibrisolvens . 相似文献
2.
Yoshinari Maeda Kiyoshi Yoshimura Hiroto Matsui Yoshitaro Shindo Takao Tamesa Yukio Tokumitsu Noriaki Hashimoto Yoshihiro Tokuhisa Kazuhiko Sakamoto Kouhei Sakai Yutaka Suehiro Yuji Hinoda Koji Tamada Shigefumi Yoshino Shoichi Hazama Masaaki Oka 《Cancer immunology, immunotherapy : CII》2015,64(8):1047-1056
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J Murata I Saiki I Azuma N Nishi 《International journal of biological macromolecules》1989,11(2):97-99
A new type of polypeptide containing the repeating sequence of cell attachment site in laminin, poly(Tyr-Ile-Gly-Ser-Arg), was synthesized by the polymerization procedure with diphenylphosphoryl azide (DPPA). We found that this polypeptide inhibited the metastatic formation in the lung of malignant tumour cells far more effectively than pentapeptide. 相似文献
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Yeqi Nian Jasper Iske Ryoichi Maenosono Koichiro Minami Timm Heinbokel Markus Quante Yang Liu Haruhito Azuma Jinrui Yang Reza Abdi Hao Zhou Abdallah Elkhal Stefan G. Tullius 《Aging cell》2021,20(2)
Age impacts alloimmunity. Effects of aging on T‐cell metabolism and the potential to interfere with immunosuppressants have not been explored yet. Here, we dissected metabolic pathways of CD4+ and CD8+ T cells in aging and offer novel immunosuppressive targets. Upon activation, CD4+ T cells from old mice failed to exhibit adequate metabolic reprogramming resulting into compromised metabolic pathways, including oxidative phosphorylation (OXPHOS) and glycolysis. Comparable results were also observed in elderly human patients. Although glutaminolysis remained the dominant and age‐independent source of mitochondria for activated CD4+ T cells, old but not young CD4+ T cells relied heavily on glutaminolysis. Treating young and old murine and human CD4+ T cells with 6‐diazo‐5‐oxo‐l‐norleucine (DON), a glutaminolysis inhibitor resulted in significantly reduced IFN‐γ production and compromised proliferative capacities specifically of old CD4+ T cells. Of translational relevance, old and young mice that had been transplanted with fully mismatched skin grafts and treated with DON demonstrated dampened Th1‐ and Th17‐driven alloimmune responses. Moreover, DON diminished cytokine production and proliferation of old CD4+ T cells in vivo leading to a significantly prolonged allograft survival specifically in old recipients. Graft prolongation in young animals, in contrast, was only achieved when DON was applied in combination with an inhibition of glycolysis (2‐deoxy‐d‐glucose, 2‐DG) and OXPHOS (metformin), two alternative metabolic pathways. Notably, metabolic treatment had not been linked to toxicities. Remarkably, immunosuppressive capacities of DON were specific to CD4+ T cells as adoptively transferred young CD4+ T cells prevented immunosuppressive capacities of DON on allograft survival in old recipients. Depletion of CD8+ T cells did not alter transplant outcomes in either young or old recipients. Taken together, our data introduce an age‐specific metabolic reprogramming of CD4+ T cells. Targeting those pathways offers novel and age‐specific approaches for immunosuppression. 相似文献
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A low-pressure microwave-induced helium plasma serves as an excitation source for metal chlorides, nitrates, and sulfates vaporized from a filament, resulting in fractional vaporization and differential sensitivities of detection of the elements depending on the vapor pressures of their salts. The shapes of the single emission peaks, which are simple in the presence of potassium chloride, become complex and may double in number. 相似文献
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The mitogenic activity of the cell-wall skeleton (CWS) of Nocardia rubra on purified splenic T-cells (thymus-derived lymphocytes) was investigated. N. rubra CWS showed remarkable mitogenic activity on normal spleen cells of C57BL/6J mice at concentrations ranging from 10 to 100 microgram per milliliter of culture medium, while, on purified splenic T-cells, N. rubra CWS did not act as an mitogen at any concentration. However, mitogenic activity of N. rubra CWS on T-cells was restored if purified splenic T-cells was reconstituted with X-irradiated peritoneal exudate cells (macrophages). The above results suggest the necessity of macrophages for T-lymphocyte activation by N. rubra CWS as well as PHA-P or Con A. 相似文献
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