目的：了解深圳市宝安区剖宫产的指征构成及其影响因素。方法：采用分层整群抽样的方法,调查2009年10~12月在宝安区分娩的剖宫产及阴道产各800例产妇的相关资料,分析剖宫产指征构成及其影响因素。结果：800例剖宫产的指征中,排位前5位...目的：了解深圳市宝安区剖宫产的指征构成及其影响因素。方法：采用分层整群抽样的方法,调查2009年10~12月在宝安区分娩的剖宫产及阴道产各800例产妇的相关资料,分析剖宫产指征构成及其影响因素。结果：800例剖宫产的指征中,排位前5位的指征为社会因素（占19.38%）、胎儿因素（占25.13%）、异常妊娠分娩史（占20.13%）、胎位异常（占12.75%）、胎盘羊水异常（占8.75%）。排位前5位的医学指征为疤痕子宫（占24.70%）、胎儿宫内窘迫（占19.01%）、臀位（占8.97%）、巨大儿（占5.20%）、活跃期停滞（占4.32%）。主要社会因素为产妇怕痛、不想受＂二茬罪＂、不想增加胎儿围产期缺氧及产伤的风险、家属不想焦急等待、经济条件许可等。经多元Logistic回归分析,5个因素对是否选择剖宫产有统计学意义,即产检总次数≥8次（OR=2.12,OR95%CI：1.74~2.50）、初产妇（OR=2.35,OR95%CI：1.77~3.29）、产时出血量≥220 m l（OR=1.72,OR95%C：I 1.31~2.13）、产妇年龄≥30岁（OR=1.56,OR95%CI：1.23~1.89）和有合并症及并发症（OR=2.31,OR95%C：I 1.75~2.87）。结论：宝安区剖宫产指征构成中,社会因素及疤痕子宫的比例大,针对性地对产妇及家属进行宣教及干预,有利于降低剖宫产率。展开更多
RxLR effectors produced by Phytophthora pathogens have been proposed to bind to phosphatidylinositol 3-phosphate （Ptdlns（3）P） to mediate their translocation into host cells and/or to increase their stability in pl...RxLR effectors produced by Phytophthora pathogens have been proposed to bind to phosphatidylinositol 3-phosphate （Ptdlns（3）P） to mediate their translocation into host cells and/or to increase their stability in planta. Since the levels of Ptdlns（3）P in plants are low, we examined whether Phytophthora species may produce Ptdlns（3）P to pro- mote infection. We observed that Ptdlns（3）P-specific GFP biosensors could bind to P. parasitica and P. sojae hyphae dur- ing infection of Nicotiana benthamiana leaves transiently secreting the biosensors, suggesting that the hyphae exposed Ptdlns（3）P on their plasma membrane and/or secreted Ptdlns（3）R Silencing of the phosphatidylinositol 3-kinases （PI3K） genes, treatment with LY294002, or expression of Ptdlns（3）pobinding proteins by P. sojae reduced the virulence of the pathogen on soybean, indicating that pathogen-synthesized Ptdlns（3）P was required for full virulence. Secretion of Ptdlns（3）P-binding proteins or of a PI3P-5-kinase by N. benthamiana leaves significantly increased the level of resist- ance to infection by P. parasitica and P. capsici. Together, our results support the hypothesis that Phytophthora species produce external Ptdlns（3）P to aid in infection, such as to promote entry of RxLR effectors into host cells. Our results derived from P. sojae RxLR effector Avrlb confirm that both the N-terminus and the C-terminus of this effector can bind Ptdlns（3）P.展开更多
The original online version of this article (Ghozlan, M.H., EL-Argawy, E., Tokgöz, S., Lakshman, D.K. and Mitra, A. (2020) Plant Defense against Necrotrophic Pathogens. American Journal of Plant Sciences, 11, 212...The original online version of this article (Ghozlan, M.H., EL-Argawy, E., Tokgöz, S., Lakshman, D.K. and Mitra, A. (2020) Plant Defense against Necrotrophic Pathogens. American Journal of Plant Sciences, 11, 2122-2138. https://doi.org/10.4236/ajps.2020.1112149) was published mistakenly without another co-author, Nikita Gambhir. In this regard, we revise authors and “how to cite” sections by adding her name.展开更多
For an advanced aircraft, the amount of its effectors is much more than that for a traditional one, the functions of effectors are more complex and the coupling between each other is more severe. Based on the current ...For an advanced aircraft, the amount of its effectors is much more than that for a traditional one, the functions of effectors are more complex and the coupling between each other is more severe. Based on the current control allocation research, this paper puts forward the concept and framework of the control allocation and management system for aircrafts with redundancy con-trol effectors. A new optimal control allocation method, bases sequenced optimal (BSO) method, is then presented. By analyz-ing the physical meaning of the allocation process of BSO method, four types of management strategies are adopted by the system, which act on the control allocation process under different flight conditions, mission requirements and effectors work-ing conditions. Simulation results show that functions of the control allocation system are extended and the system adaptability to flight status, mission requirements and effector failure conditions is improved.展开更多
Salicylic acid (SA) or 2-hydroxybenoic acid is a phenolic plant hormone that plays an essential role in plant defense against biotrophic and semi-biotrophic pathogens. In Arabidopsis, SA is synthesized from chorismate...Salicylic acid (SA) or 2-hydroxybenoic acid is a phenolic plant hormone that plays an essential role in plant defense against biotrophic and semi-biotrophic pathogens. In Arabidopsis, SA is synthesized from chorismate in the chloroplast through the ICS1 (isochorismate synthase I) pathway during pathogen infectioru The transcription co-activator NPR1 (Non-Expresser of Pathogenesis-Related Gene 1), as the master regulator of SA signaling, interacts with transcription factors to induce the expression of anti-microbial PR (Pathogenesis-Related) genes. To establish successful in fections, plant bacterial, oomycete, fun gal, and viral pathogens have evolved at least three major strategies to disrupt SA-mediated defense? The first strategy is to reduce SA accumulation directly by converting SA into its inactive derivatives. The second strategy is to interrupt SA biosynthesis by targeting the ICS1 pathway. In the third major strategy, plant pathogens deploy different mechanisms to interfere with SA downstream signaling. The wide array of strategies deployed by plant pathogens highlights the crucial role of disruption of SA-mediated plant defense in plant pathogenesis. A deeper understanding of this topic will greatly expand our knowledge of how plant pathogens cause diseases and consequently pave the way for the development of more effective ways to corn trol these diseases.展开更多
Hemipteran and dipteran insects have behavioral,cellular and chemical strategies for evading or coping with the host plant defenses making these insects particularly destructive pests worldwide. A critical component o...Hemipteran and dipteran insects have behavioral,cellular and chemical strategies for evading or coping with the host plant defenses making these insects particularly destructive pests worldwide. A critical component of a host plant＇s defense to herbivory is innate immunity. Here we review the status of our understanding of the receptors that contribute to perception of hemipteran and dipteran pests and highlight the gaps in our knowledge in these early events in immune signaling. We also highlight recent advances in identification of the effectors that activate pattern-triggered immunity and those involved in effector-triggered immunity.展开更多
Phytopathogenic fungi secrete a large arsenal of effector molecules,including proteinaceous effectors,small RNAs,phytohormones and derivatives thereof.The pathogenicity of fungal pathogens is primarily determined by t...Phytopathogenic fungi secrete a large arsenal of effector molecules,including proteinaceous effectors,small RNAs,phytohormones and derivatives thereof.The pathogenicity of fungal pathogens is primarily determined by these effectors that are secreted into host cells to undermine innate immunity,as well as to facilitate the acquisition of nutrients for their in planta growth and proliferation.After conventional and non-conventional secretion,fungal effectors are translocated into different subcellular compartments of the host cells to interfere with various biological processes.In extracellular spaces,apoplastic effectors cope with physical and chemical barriers to break the first line of plant defenses.Intracellular effectors target essential immune components on the plasma membrane,in the cytosol,including cytosolic organelles,and in the nucleus to suppress host immunity and reprogram host physiology,favoring pathogen colonization.In this review,we comprehensively summarize the recent advances in fungal effector biology,with a focus on the versatile virulence functions of fungal effectors in promoting pathogen infection and colonization.A perspective of future research on fungal effector biology is also discussed.展开更多
Alternative splicing(AS)of pre-mRNAs increases transcriptome and proteome diversity,regulates gene expression through multiple mechanisms,and plays important roles in plant development and stress responses.However,the...Alternative splicing(AS)of pre-mRNAs increases transcriptome and proteome diversity,regulates gene expression through multiple mechanisms,and plays important roles in plant development and stress responses.However,the prevalence of genome-wide plant AS changes during infection and the mechanisms by which pathogens modulate AS remain poorly understood.Here,we examined the global AS changes in tomato leaves infected with Phytophthora infestans,the infamous Irish famine pathogen.We show that more than 2000 genes exhibiting significant changes in AS are not differentially expressed,indicating that AS is a distinct layer of transcriptome reprogramming during plant-pathogen interactions.Furthermore,our results show that P.infestans subverts host immunity by repressing the AS of positive regulators of plant immunity and promoting the AS of susceptibility factors.To study the underlying mechanism,we established a luminescence-based AS reporter system in Nicotiana benthamiana to screen pathogen effectors modulating plant AS.We identified nine splicing regulatory effectors(SREs)from 87 P.infestans effectors.Further studies revealed that SRE3 physically binds U1-70K to manipulate the plant AS machinery and subsequently modulates AS-mediated plant immunity.Our study not only unveils genome-wide plant AS reprogramming during infection but also establishes a novel AS screening tool to identify SREs from a wide range of plant pathogens,providing opportunities to understand the splicing regulatory mechanisms through which pathogens subvert plant immunity.展开更多
文摘目的：了解深圳市宝安区剖宫产的指征构成及其影响因素。方法：采用分层整群抽样的方法,调查2009年10~12月在宝安区分娩的剖宫产及阴道产各800例产妇的相关资料,分析剖宫产指征构成及其影响因素。结果：800例剖宫产的指征中,排位前5位的指征为社会因素（占19.38%）、胎儿因素（占25.13%）、异常妊娠分娩史（占20.13%）、胎位异常（占12.75%）、胎盘羊水异常（占8.75%）。排位前5位的医学指征为疤痕子宫（占24.70%）、胎儿宫内窘迫（占19.01%）、臀位（占8.97%）、巨大儿（占5.20%）、活跃期停滞（占4.32%）。主要社会因素为产妇怕痛、不想受＂二茬罪＂、不想增加胎儿围产期缺氧及产伤的风险、家属不想焦急等待、经济条件许可等。经多元Logistic回归分析,5个因素对是否选择剖宫产有统计学意义,即产检总次数≥8次（OR=2.12,OR95%CI：1.74~2.50）、初产妇（OR=2.35,OR95%CI：1.77~3.29）、产时出血量≥220 m l（OR=1.72,OR95%C：I 1.31~2.13）、产妇年龄≥30岁（OR=1.56,OR95%CI：1.23~1.89）和有合并症及并发症（OR=2.31,OR95%C：I 1.75~2.87）。结论：宝安区剖宫产指征构成中,社会因素及疤痕子宫的比例大,针对性地对产妇及家属进行宣教及干预,有利于降低剖宫产率。
基金This work was supported by grants from the National Natural Science Foundation of China （No. 30971889）, National Science and Technology Major Projects （No. 2009ZX08005-003B）, and the Natural Science Foundation of Jiangsu Province （No. BK2012027）.We appreciate Prof. Brett Tyler （Oregon State） for manuscript preparation, and Yuanming Zhang （Nanjing Agricultural University） for suggestions in data analysis. No conflict of interest declared.
文摘RxLR effectors produced by Phytophthora pathogens have been proposed to bind to phosphatidylinositol 3-phosphate （Ptdlns（3）P） to mediate their translocation into host cells and/or to increase their stability in planta. Since the levels of Ptdlns（3）P in plants are low, we examined whether Phytophthora species may produce Ptdlns（3）P to pro- mote infection. We observed that Ptdlns（3）P-specific GFP biosensors could bind to P. parasitica and P. sojae hyphae dur- ing infection of Nicotiana benthamiana leaves transiently secreting the biosensors, suggesting that the hyphae exposed Ptdlns（3）P on their plasma membrane and/or secreted Ptdlns（3）R Silencing of the phosphatidylinositol 3-kinases （PI3K） genes, treatment with LY294002, or expression of Ptdlns（3）pobinding proteins by P. sojae reduced the virulence of the pathogen on soybean, indicating that pathogen-synthesized Ptdlns（3）P was required for full virulence. Secretion of Ptdlns（3）P-binding proteins or of a PI3P-5-kinase by N. benthamiana leaves significantly increased the level of resist- ance to infection by P. parasitica and P. capsici. Together, our results support the hypothesis that Phytophthora species produce external Ptdlns（3）P to aid in infection, such as to promote entry of RxLR effectors into host cells. Our results derived from P. sojae RxLR effector Avrlb confirm that both the N-terminus and the C-terminus of this effector can bind Ptdlns（3）P.
文摘The original online version of this article (Ghozlan, M.H., EL-Argawy, E., Tokgöz, S., Lakshman, D.K. and Mitra, A. (2020) Plant Defense against Necrotrophic Pathogens. American Journal of Plant Sciences, 11, 2122-2138. https://doi.org/10.4236/ajps.2020.1112149) was published mistakenly without another co-author, Nikita Gambhir. In this regard, we revise authors and “how to cite” sections by adding her name.
基金supported by the National Natural Science Foundation of China (Grant No. 60804007)the Aviation Science Funds of China (Grant No. 20080751018)
文摘For an advanced aircraft, the amount of its effectors is much more than that for a traditional one, the functions of effectors are more complex and the coupling between each other is more severe. Based on the current control allocation research, this paper puts forward the concept and framework of the control allocation and management system for aircrafts with redundancy con-trol effectors. A new optimal control allocation method, bases sequenced optimal (BSO) method, is then presented. By analyz-ing the physical meaning of the allocation process of BSO method, four types of management strategies are adopted by the system, which act on the control allocation process under different flight conditions, mission requirements and effectors work-ing conditions. Simulation results show that functions of the control allocation system are extended and the system adaptability to flight status, mission requirements and effector failure conditions is improved.
基金The National Science Foundation (grant IOS-1758994 to Z.Q.F.)M.C.is supported by the Postdoctoral Workstation of Jiangsu Academy of Agricultural Sciences.
文摘Salicylic acid (SA) or 2-hydroxybenoic acid is a phenolic plant hormone that plays an essential role in plant defense against biotrophic and semi-biotrophic pathogens. In Arabidopsis, SA is synthesized from chorismate in the chloroplast through the ICS1 (isochorismate synthase I) pathway during pathogen infectioru The transcription co-activator NPR1 (Non-Expresser of Pathogenesis-Related Gene 1), as the master regulator of SA signaling, interacts with transcription factors to induce the expression of anti-microbial PR (Pathogenesis-Related) genes. To establish successful in fections, plant bacterial, oomycete, fun gal, and viral pathogens have evolved at least three major strategies to disrupt SA-mediated defense? The first strategy is to reduce SA accumulation directly by converting SA into its inactive derivatives. The second strategy is to interrupt SA biosynthesis by targeting the ICS1 pathway. In the third major strategy, plant pathogens deploy different mechanisms to interfere with SA downstream signaling. The wide array of strategies deployed by plant pathogens highlights the crucial role of disruption of SA-mediated plant defense in plant pathogenesis. A deeper understanding of this topic will greatly expand our knowledge of how plant pathogens cause diseases and consequently pave the way for the development of more effective ways to corn trol these diseases.
基金supported by National Institute of Food and Agriculture(Award No.2010-65106-20675)supported by the National Science Foundation(Award No.IOS-072093 and IOSEAGER-1450331)Bill&Melinda Gates Foundation via a subcontract(B0426×5)from the National Research Institute,University of Greenwich,UK
文摘Hemipteran and dipteran insects have behavioral,cellular and chemical strategies for evading or coping with the host plant defenses making these insects particularly destructive pests worldwide. A critical component of a host plant＇s defense to herbivory is innate immunity. Here we review the status of our understanding of the receptors that contribute to perception of hemipteran and dipteran pests and highlight the gaps in our knowledge in these early events in immune signaling. We also highlight recent advances in identification of the effectors that activate pattern-triggered immunity and those involved in effector-triggered immunity.
基金The work is supported by the National Natural Science Foundation of China(31630064,U19A2027,and 31770140)to WS。
文摘Phytopathogenic fungi secrete a large arsenal of effector molecules,including proteinaceous effectors,small RNAs,phytohormones and derivatives thereof.The pathogenicity of fungal pathogens is primarily determined by these effectors that are secreted into host cells to undermine innate immunity,as well as to facilitate the acquisition of nutrients for their in planta growth and proliferation.After conventional and non-conventional secretion,fungal effectors are translocated into different subcellular compartments of the host cells to interfere with various biological processes.In extracellular spaces,apoplastic effectors cope with physical and chemical barriers to break the first line of plant defenses.Intracellular effectors target essential immune components on the plasma membrane,in the cytosol,including cytosolic organelles,and in the nucleus to suppress host immunity and reprogram host physiology,favoring pathogen colonization.In this review,we comprehensively summarize the recent advances in fungal effector biology,with a focus on the versatile virulence functions of fungal effectors in promoting pathogen infection and colonization.A perspective of future research on fungal effector biology is also discussed.
基金the Chinese National Science Fund(31901862,31772144,31721004)Natural Science Foundation of Jiangsu Province(SBK2019040604)+1 种基金China Postdoctoral Science Foundation(2018M640494)the Fundamental Research Funds for the Central Uni-versities(JCQY201904,KYXK202010).
文摘Alternative splicing(AS)of pre-mRNAs increases transcriptome and proteome diversity,regulates gene expression through multiple mechanisms,and plays important roles in plant development and stress responses.However,the prevalence of genome-wide plant AS changes during infection and the mechanisms by which pathogens modulate AS remain poorly understood.Here,we examined the global AS changes in tomato leaves infected with Phytophthora infestans,the infamous Irish famine pathogen.We show that more than 2000 genes exhibiting significant changes in AS are not differentially expressed,indicating that AS is a distinct layer of transcriptome reprogramming during plant-pathogen interactions.Furthermore,our results show that P.infestans subverts host immunity by repressing the AS of positive regulators of plant immunity and promoting the AS of susceptibility factors.To study the underlying mechanism,we established a luminescence-based AS reporter system in Nicotiana benthamiana to screen pathogen effectors modulating plant AS.We identified nine splicing regulatory effectors(SREs)from 87 P.infestans effectors.Further studies revealed that SRE3 physically binds U1-70K to manipulate the plant AS machinery and subsequently modulates AS-mediated plant immunity.Our study not only unveils genome-wide plant AS reprogramming during infection but also establishes a novel AS screening tool to identify SREs from a wide range of plant pathogens,providing opportunities to understand the splicing regulatory mechanisms through which pathogens subvert plant immunity.
