酸铝胁迫土壤中耐铝大豆根际不同部位细菌群落结构、功能及其对促生菌富集作用的研究

针对酸性土壤中影响作物生产的主要限制因子(pH及其铝毒),选用耐酸铝且具有固氮能力的豆科作物是改良该类土壤、促进农业生产的有效措施之一,至于其所关联的根际微生物是否起到相应的促进作用,一直为国内外学者所关注和探究。为此,本研究以铝耐受型大豆品种基因型(BX10)和铝敏感型大豆品种基因型(BD2)为材料,以酸性红壤为生长介质,采样部位按照土层到根系的距离由远到近的顺序划分为:根外对照土(bulk soil,BS)、两侧根际土(rhizospheric soil at two sides,SRH)、刷后根际土(rhizospheric soil after brush,BRH)和冲洗后的根际土(rhizospheric soil after wash,WRH)。利用Illumina MiSeq对16S rRNA基因扩增产物的高变区V4进行高通量测序,研究了不同耐铝基因型大豆根际细菌群落的结构、功能与分子遗传多样性的差异性作用。结果表明,各处理间大豆根际细菌群落的alpha多样性无显著性差异,beta多样性差异也均不显著。PCA和PCoA分析可见BRH和WRH部位的物种组成较为一致,而BS和SRH部位具有相似的物种组成,说明植物生长主要影响根际的BRH及WRH部位的微生物,对SRH影响较小。对各分类水平物种组成和丰度进行比较,门分类水平三元图表明两个基因型大豆均在WRH部位富集蓝细菌门(Cyanobacteria)细菌;统计分析表明铝耐受型大豆(BX10)根部对于增强植物抗逆性的植物根际促生菌(plant growth promoting rhizobacteria,PGPR)有富集作用,这些富集的细菌包括蓝细菌门、拟杆菌门(Bacteroidetes)和变形菌门(Proteobacteria)等,以及部分与固氮和耐铝的功能相关的属种。另对同一个基因型大豆不同采样部位间进行比较分析,结果显示土壤不同采样部位可以选择性富集不同的PGPR物种。此外,16S rDNA的同源蛋白簇(clusters of orthologous groups of proteins,COG)功能预测分析的结果表明,多个COG包括COG0347、COG1348、COG1433、COG2710、COG3870、COG4656、COG5420、COG5456和COG5554均可能与固氮直接相关;BD2相比于BX10,结果显示在BRH和WRH部位似乎均更易富集固氮直接相关的COG,其可能的原因尚待进一步研究。

Research on Agricultural Co-efficiency of Farmer Professional Cooperative Unions

Various farmer professional cooperative unions( FPCUs) have emerged and flourished along with the development of rural economy in recent years. Compared with the independent cooperatives,the FPCUs can integrate the union's structure and have more cooperation in business. In a wider range,it can also let every member of the union exchange the market information efficiently,and adjust the circulation of cash products,share the technology,generate a mechanism to complement each other's advantages and help each other. The basic situation and effects of farmer professional cooperative unions in Jingzhou City of Hubei Province are analyzed in this paper,by selecting Jing Chu Fu Min Agricultural Cooperative Union,Jianli Fu Wa San Feng Farmer Specialized Cooperative Union and Honghu Chun Lu Agricultural Cooperative Union as typical cases. The prominent problems in the agricultural cooperation are analyzed emphatically,and then the corresponding measures and suggestions are put forward.

Transcription factors T-bet/GATA-3/Foxp3 in peripheral blood of patients with chronic otitis media with effusion

To the Editor:Otitis media with effusion(OME),also known as secretory otitis,is a disease in which secreted fluid accumulates in the middle ear cavity and is a major cause of hearing loss,both in children and adults.[1]Causes of OME include recurrent infections,inflammatory conditions,malformations,and eustachian tube dysfunctions.[2]Although most patients could recover spontaneously,by medication,or by surgery,some patients show frequent recurrence of otitis media for more than 3 months,called chronic otitis media with effusion(COME).[1]The pathogenesis of COME is not completely understood.Increasing evidence suggests a central role of immunologic cells and th&r associated cytokines in the chronic inflammation that characterizes COME.

Psychological impact of COVID-19 on medical care workers in China

Background Medical care workers experienced unprecedented levels of workload and pressure since the outbreak of coronavirus disease 2019(COVID-19).Little is known about its exact impact on medical care workers and related factors in China.This study aims to identify the psychological impact of COVID-19 on medical care workers in China.Methods From February 23 to March 5,2020,a cross-sectional survey was conducted among 863 medical care workers from seven provinces in China using standard questionnaires measuring adverse psychological outcomes including Impact of Event Scale-6(IES-6),Depression,Anxiety and Stress Scale(DASS)and related psychosocial factors like perceived threat,social support and coping strategies.Exploratory Factor analysis was performed to identify the dimensions of perceived threat by study participants.Multivariate regression was used to examine the determinants of adverse psychological outcomes.Results Posttraumatic stress(PTS)were prevalent in this sample of health care professionals,and 40.2%indicated positive screens for significant posttraumatic stress disorder symptoms.The proportion of having mild to extremely severe symptoms of depression,anxiety and stress were 13.6,13.9 and 8.6%,respectively.Perceived threat and passive coping strategies were positively correlated to PTS and DASS scores,while perceived social support and active coping strategies were negatively correlated to DASS scores.Nurses were more likely to be anxious than others among medical care workers during the COVID-19 epidemic.Conclusions Adverse psychological symptoms were prevalent among medical care workers in China during the COVID-19 epidemic.Screening for adverse psychological outcomes and developing corresponding preventive measures would be beneficial in decreasing negative psychological outcomes.

Fighting against the common enemy of COVID-19: a practice of building a community with a shared future for mankind

The outbreak of coronavirus disease 2019(COVID-19)has caused more than 80813 confirmed cases in all provinces of China,and 21110 cases reported in 93 countries of six continents as of 7 March 2020 since middle December 2019.Due to biological nature of the novel coronavirus,named severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)with faster spreading and unknown transmission pattern,it makes us in a difficulty position to contain the disease transmission globally.To date,we have found it is one of the greatest challenges to human beings in fighting against COVID-19 in the history,because SARS-CoV-2 is different from SARS-CoV and MERS-CoV in terms of biological features and transmissibility,and also found the containment strategies including the non-pharmaceutical public health measures implemented in China are effective and successful.In order to prevent a potential pandemic-level outbreak of COVID-19,we,as a community of shared future for mankind,recommend for all international leaders to support preparedness in low and middle income countries especially,take strong global interventions by using old approaches or new tools,mobilize global resources to equip hospital facilities and supplies to protect noisome infections and to provide personal protective tools such as facemask to general population,and quickly initiate research projects on drug and vaccine development.We also recommend for the international community to develop better coordination,cooperation,and strong solidarity in the joint efforts of fighting against COVID-19 spreading recommended by the joint mission report of the WHO-China experts,against violating the International Health Regulation(WHO,2005),and against stigmatization,in order to eventually win the battle against our common enemy—COVID-19.

STIM1 promotes acquired resistance to sorafenib by attenuating ferroptosis in hepatocellular carcinoma

Dysregulated calcium(Ca?+)signaling pathways are associated with tumor cell death and drug resistance.In non-excitable cells,such as hepatocellular carcinoma(HcC)cells,the primary pathway for Ca2+influx is through stromal interaction molecule 1(STIM1)-mediated store-operated calcium entry(SOCE).Previous studies have demonstrated the involvement of STIM1-mediated SOCE in processes such as genesis,metastasis,and stem cell self-renewal of HCC.However,it remains unclear whether STIM1-mediated SOCE plays a role in developing acquired resistance to sorafenib in HcC patients.In this study,we established acquired sorafenib-resistant(SR)HCC cell lines by intermittently exposing them to increasing concentrations of sorafenib.Our results showed higher levels of STIM1 and stronger SOCE in SR cells compared with parental cells.Deleting STIM1 significantly enhanced sensitivity to sorafe-nib in SR cells,while overexpressing STIM1 promoted SR by activating SOCE.Mechanistically,STIM1 increased the transcription of SLC7A11 through the SOCE-CaN-NFAT pathway.Subse-quently,up-regulated SLC7A11 increased glutathione synthesis,resulting in ferroptosis insen-sitivity and SR.Furthermore,combining the SOCE inhibitor SKF96365 with sorafenib significantly improved the sensitivity of sR cells to sorafenib both in vitro and in vivo.These findings suggest a potential strategy to overcome acquired resistance to sorafenib in HcC cells.