采用溶磷平板筛选和重金属耐性复筛相结合,从薇甘菊根际分离到一株兼具多重金属抗性的溶磷细菌(编号为ZLT11),16S r RNA基因序列分析显示,该菌株属于类芽孢杆菌。菌株对植酸钙和植酸的溶磷量分别为84.10和73.84 mg·L^-1,其在30℃...采用溶磷平板筛选和重金属耐性复筛相结合,从薇甘菊根际分离到一株兼具多重金属抗性的溶磷细菌(编号为ZLT11),16S r RNA基因序列分析显示,该菌株属于类芽孢杆菌。菌株对植酸钙和植酸的溶磷量分别为84.10和73.84 mg·L^-1,其在30℃、初始pH为9.0时对植酸钙的溶磷量最高,达95.66 mg·L^-1。菌株ZLT11能耐受≤400 mg·L^-1Pb^2+、≤100mg·L^-1Cd^2+及≤40 mg·L^-1Hg^2+,当添加植酸钙为磷源时,接种菌株ZLT11使水稻幼苗平均根长、根数、苗高和总生物量较对照幼苗分别增加106.7%、76.6%、49.0%和46.3%。菌株ZLT11还能显著促进水稻幼苗在Cd胁迫下的生长。展开更多
Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to surv...Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to survive. This paper investigates the spatiotemporal characteristics and mechanisms of urban-rural eco-land using a new and innovative integration way based on eco-land change data in China's Loess Plateau(LP) prefecture level cities and explores factors of eco-land change. The spatial difference characteristic of eco-land among different level cities in the LP is that: small cities > big cities > middle cities. From 2009 to 2016, the eco-land in the LP from the perspective of urban-rural areas has changed significantly. Significant differences of urban-rural eco-land were identified among various urban growth types, and all the cities in the LP were further classified into four types based on eco-land change trend, with type A and B cities identified as the vital zone and major zone. Taking the eco-fragile region Loess Plateau(LP) as an example, our results demonstrated that the migrants to cities in LP could relieve ecological pressures and promote restoration of ecological vegetation. We have demonstrated that urbanization and the influence of government policy can be discerned through the quantification of the spatial-temporal change of eco-land and suggest that combining both urban and rural eco-land can support more effective land use decisions and provide theoretical basis for the practical application of urban planning, policy-making and sustainable development. What's more, governments should strive to population mobility and restore vegetation to sustain this fragile ecological environment.展开更多
Myasthenia gravis(MG) is a prototypical antibody-mediated neurological autoimmune disease with the involvement of humoral immune responses in its pathogenesis. T follicular helper(Tfh) cells have been implicated in ma...Myasthenia gravis(MG) is a prototypical antibody-mediated neurological autoimmune disease with the involvement of humoral immune responses in its pathogenesis. T follicular helper(Tfh) cells have been implicated in many autoimmune diseases. However, whether and how Tfh cells are involved in MG remain unclear.Here, we established and studied a widely-used and approved animal model of human MG, the rat model with acetylcholine receptor alpha(AChRa) subunit(RAChR97–116)-induced experimental autoimmune myasthenia gravis(EAMG). This model presented mild bodyweight loss 10 days after the first immunization(representing the early stage of disease) and more obvious clinical manifestations and body-weight loss 7 days after the second immunization(representing the late stage of disease). AChR-specific pre-Tfh cells and mature Tfh cells were detected in these two stages, respectively. In cocultures of Tfh cells and B cells, the number of IgG2 bsecreting B cells and the level of anti-AChR antibodies in the supernatant were higher in the cultures containing EAMG-derived Tfh cells. In immunohistochemistry and immunofluorescence assays, a substantial number of CD4^+/Bcl-6^+ T cells and a greater number of larger germinal centers were observed in lymph node tissues resected from EAMG rats. Based on these results, wehypothesize that an AChR-specific Tfh cell-mediated humoral immune response contributes to the development of EAMG.展开更多
基金funded by the National Key Research and Development Program of China (Grant No.2017YFC0504701)National Natural Science Foundation of China (Grant Nos.41130748 and 41471143)the National Social Science Foundation of China (Grant No 15ZDA021)
文摘Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to survive. This paper investigates the spatiotemporal characteristics and mechanisms of urban-rural eco-land using a new and innovative integration way based on eco-land change data in China's Loess Plateau(LP) prefecture level cities and explores factors of eco-land change. The spatial difference characteristic of eco-land among different level cities in the LP is that: small cities > big cities > middle cities. From 2009 to 2016, the eco-land in the LP from the perspective of urban-rural areas has changed significantly. Significant differences of urban-rural eco-land were identified among various urban growth types, and all the cities in the LP were further classified into four types based on eco-land change trend, with type A and B cities identified as the vital zone and major zone. Taking the eco-fragile region Loess Plateau(LP) as an example, our results demonstrated that the migrants to cities in LP could relieve ecological pressures and promote restoration of ecological vegetation. We have demonstrated that urbanization and the influence of government policy can be discerned through the quantification of the spatial-temporal change of eco-land and suggest that combining both urban and rural eco-land can support more effective land use decisions and provide theoretical basis for the practical application of urban planning, policy-making and sustainable development. What's more, governments should strive to population mobility and restore vegetation to sustain this fragile ecological environment.
基金supported by the National Natural Science Foundation of China(81000536,81471227,31371079,31671112 and 81430035)the China Postdoctoral Science Foundation(20100471094)+3 种基金the Returned Overseas Scholars Foundation of the Natural Science Foundation of Heilongjiang Province,China(LC2015029,QC2015022)the Science and Technology Research Project of the Education Department of Heilongjiang Province,China(12541z008)the Heilongjiang Province Postdoctoral Science Foundation(LBH-Q131111)the Open Topic of Key Laboratory of Neurobiology,General Colleges and Universities in Heilongjiang Province,China(2013HLJKLNT-05)
文摘Myasthenia gravis(MG) is a prototypical antibody-mediated neurological autoimmune disease with the involvement of humoral immune responses in its pathogenesis. T follicular helper(Tfh) cells have been implicated in many autoimmune diseases. However, whether and how Tfh cells are involved in MG remain unclear.Here, we established and studied a widely-used and approved animal model of human MG, the rat model with acetylcholine receptor alpha(AChRa) subunit(RAChR97–116)-induced experimental autoimmune myasthenia gravis(EAMG). This model presented mild bodyweight loss 10 days after the first immunization(representing the early stage of disease) and more obvious clinical manifestations and body-weight loss 7 days after the second immunization(representing the late stage of disease). AChR-specific pre-Tfh cells and mature Tfh cells were detected in these two stages, respectively. In cocultures of Tfh cells and B cells, the number of IgG2 bsecreting B cells and the level of anti-AChR antibodies in the supernatant were higher in the cultures containing EAMG-derived Tfh cells. In immunohistochemistry and immunofluorescence assays, a substantial number of CD4^+/Bcl-6^+ T cells and a greater number of larger germinal centers were observed in lymph node tissues resected from EAMG rats. Based on these results, wehypothesize that an AChR-specific Tfh cell-mediated humoral immune response contributes to the development of EAMG.