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971.
972.
Zhou Yang Cao Leqing Guo Huidong Hong Yan Wang Ming Wang Ke Huang Xiaojun Chang Yingjun 《中国科学:生命科学英文版》2021,64(7):1087-1096
Acute graft-versus-host disease(a GVHD) is caused by allo-activated donor T cells infiltrating target organs. As a regulator of immune function, granulocyte colony-stimulating factor(G-CSF) has been demonstrated to relieve the a GVHD reaction.However, the role of G-CSF-primed donor Tcells in specific target organs is still unknown. In this study, we employed a classical MHC-mismatched transplantation mouse model(C57BL/6 into BALB/c) and found that recipient mice transplanted with GCSF-primed T cells exhibited prolonged survival compared with that of the PBS-treated group. This protective function against GVHD mediated by G-CSF-primed donor T cells was further confirmed by decreased clinical and pathological scores in this a GVHD mouse model, especially in the lung and gut. Moreover, we found that Tcells polarized towards Th2 cells and regulatory T cells were increased in specific target organs. In addition, G-CSF treatment inhibited inducible co-stimulator(ICOS) expression and increased the expression of tolerance-related genes in recipient mice. Our study provides new insight into the immune regulatory effects of G-CSF on T cell-mediated a GVHD, especially for its precise regulation in GVHD target organs. 相似文献
973.
Ran Chao Li Yu Ma Xufa Xie Yadong Xie Mingxu Zhang Yuting Zhou Wei Yang Yalin Zhang Zhen Zhou Li Wei Kaijian Zhou Zhigang 《中国科学:生命科学英文版》2021,64(9):1437-1448
Viral diseases cause serious economic loss in farmed animals industry. However, the efficacy of remedies for viral infection in farmed animals is limited, and treatment strategies are generally lacking for aquatic animals. Interactions of commensal microbiota and viral infection have been studied in recent years, demonstrating a third player in the interaction between hosts and viruses. Here, we discuss recent developments in the research of interactions between commensal bacteria and viral infection,including both promotion and inhibition effect of commensal bacteria on viral pathogenesis, as well as the impact of viral infection on commensal microbiota. The antiviral effect of commensal bacteria is mostly achieved through priming or regulation of the host immune responses, involving differential microbial components and host signaling pathways, and gives rise to various antiviral probiotics. Moreover, we summarize studies related to the interaction between commensal bacteria and viral infection in farmed animals, including pigs, chickens, fish and invertebrate species. Further studies in this area will deepen our understanding of antiviral immunity of farmed animals in the context of commensal microbiota, and promote the development of novel strategies for treatment of viral diseases in farmed animals. 相似文献
974.
目的: 弗氏链霉菌(Streptomyces fradiae)作为氨基糖苷类抗生素新霉素的主要生产菌株,其新霉素B具有抗菌活性强、抗癌、抗HIV等作用,提高新霉素B的效价具有重要意义。方法: 在满足微生物正常生长所需盐离子的条件下,通过盐增强培养的方式向培养基中添加不同种类、浓度无机盐来改变细胞壁附近的理化特性、渗透压以及培养基中的碳氮比。结果: 不同无机盐对新霉素B效价影响程度由高到低为(NH4)2SO4、NaCl、KCl、K2SO4;当添加60 mmol/L(NH4)2SO4时新霉素B的效价达到最高为15 864 U/mL,而NaCl在80 mmol/L浓度时产量最高为7 429.7 U/mL,相比未添加无机盐分别提高3.8倍和0.82倍。在含有80 mmol/L的NaCl的发酵培养基中添加不同浓度的(NH4)2SO4并定时取样检测其中氨基氮、还原糖、pH、TG、菌浓以及新霉素B效价的变化,发现60 mmol/L(NH4)2SO4浓度下氨基氮、还原糖、TG的消耗速率加快,菌体比生长速率μ最大为0.097/h,新霉素B的合成加快且产量提高为17 399 U/mL,同时菌丝呈现出聚集变短的形态且产孢提前。结论: 盐增强培养方式既可以作为一种形态学工程手段,通过改变弗氏链霉菌的微观形态来促进次级代谢产物新霉素B产量的提高,同时也可以作为培养基优化策略来提高新霉素B的产量,这为进一步提高弗氏链霉菌中次级代谢产物产量的研究奠定了基础。 相似文献
975.
Jinnan Wang Houjun Zhou Yanqiu Zhao Cheng Jiang Jihong Li Fang Tang Yingli Liu Shutang Zhao Jianjun Hu Xueqin Song Meng‐Zhu Lu 《植物学报(英文版)》2021,63(10):1683-1694
976.
977.
978.
979.
Jinhua Xiao Xianqin Wei Yi Zhou Zhaozhe Xin Yunheng Miao Hongxia Hou Jiaxing Li Dan Zhao Jing Liu Rui Chen Liming Niu Guangchang Ma Wenquan Zhen Shunmin He Jianxia Wang Xunfan Wei Weihao Dou Zhuoxiao Sui Dawei Huang 《遗传学报》2021,48(3):225-236
Figs and fig pollinators are one of the few classic textbook examples of obligate pollination mutualism. The specific dependence of fig pollinators on the relatively safe living environment with sufficient food sources in the enclosed fig syconia implies that they are vulnerable to habitat changes. However, there is still no extensive genomic evidence to reveal the evolutionary footprint of this long-term mutually beneficial symbiosis in fig pollinators. In fig syconia, there are also non-pollinator species. The non-pollinator species differ in their evolutionary and life histories from pollinators. We conducted comparative analyses on 11 newly sequenced fig wasp genomes and one previously published genome. The pollinators colonized the figs approximately 66.9 million years ago, consistent with the origin of host figs. Compared with nonpollinators, many more genes in pollinators were subject to relaxed selection. Seven genes were absent in pollinators in response to environmental stress and immune activation. Pollinators had more streamlined gene repertoires in the innate immune system, chemosensory toolbox, and detoxification system. Our results provide genomic evidence for the differentiation between pollinators and nonpollinators. The data suggest that owing to the long-term adaptation to the fig, some genes related to functions no longer required are absent in pollinators. 相似文献
980.
Xi Zhang Tianhang Qiu Anan Wang Huajian Zhou Min Yuan Li Li Sulan Bai Suxia Cui 《植物学报》2021,55(6):693
为探明北京地区芦苇(Phragmites australis)的资源状态和多样性, 实地考察北京主要河流、湿地和水库, 发现北京地区芦苇总生长面积已超过600 hm2。芦苇染色体倍性以八倍体为主, 四倍体次之。在面积较大的湿地内, 八倍体单一芦苇群落占据优势地位; 而在城市的浅河内有形态和遗传性多样的混合种群。研究表明, 植物性状和倍性水平之间无显著相关性。在小清河发现了6种形态各异的芦苇克隆, 均属于叶绿体DNA片段的P单倍型; 其单倍体基因组大小为(0.499±0.019) pg, 变异系数为3.8%。这表明表型与单倍型之间也不具相关性。此外, 发现1个具有变叶特性的芦苇, 将其命名为金条芦苇。北京地区芦苇形态和遗传多样性为研究芦苇基因型与环境适应性之间的关系提供了珍贵的资源。 相似文献