目的通过实验室检测技术分析1名输入性发热病例的病毒性病原体,并判定其型别,为临床防治提供实验室依据。方法将采集到的血标本采用实时荧光定量聚合酶链式反应(Real time PCR)检测登革病毒核酸,使用通用引物和型特异性引物行逆转录-套...目的通过实验室检测技术分析1名输入性发热病例的病毒性病原体,并判定其型别,为临床防治提供实验室依据。方法将采集到的血标本采用实时荧光定量聚合酶链式反应(Real time PCR)检测登革病毒核酸,使用通用引物和型特异性引物行逆转录-套式PCR扩增保守区域特异性核酸片段进行型别鉴定,通过登革病毒E基因扩增和序列测定对登革病毒进行亚型基因分型。结果病例血标本核酸经RT-PCR和逆转录-套式PCR方法鉴定为登革病毒2型(DENV-2),基因分类属于DENV-2全球型。结论该例输入性疑似登革热病例系DENV-2全球型引起。展开更多
Dengue has been well recognized as a global public health threat,but only sporadic epidemics and imported cases were reported in recent decades in China.Since July 2014,an unexpected large dengue outbreak has occurred...Dengue has been well recognized as a global public health threat,but only sporadic epidemics and imported cases were reported in recent decades in China.Since July 2014,an unexpected large dengue outbreak has occurred in Guangdong province,China,resulting in more than 40000 patients including six deaths.To clarify and characterize the causative agent of this outbreak,the acute phase serum from a patient diagnosed with severe dengue was subjected to virus isolation and high-throughput sequencing(HTS).Traditional real-time RT-PCR and HTS with Ion Torrent PGM detected the presence of dengue virus serotype 2(DENV-2).A clinical DENV-2 isolate GZ05/2014 was obtained by culturing the patient serum in mosquito C6/36 cells.The complete genome of GZ05/2014 was determined and deposited in Gen Bank under the access number KP012546.Phylogenetic analysis based on the complete envelope gene showed that the newly DENV-2 isolate belonged to Cosmopolitan genotype and clustered closely with other Guangdong strains isolated in the past decade.No amino acid mutations that are obviously known to increase virulence or replication were identified throughout the genome of GZ05/2014.The high homology of Guangdong DENV-2 strains indicated the possibility of establishment of local DENV-2 circulation in Guangdong,China.These results help clarify the origin of this epidemic and predict the future status of dengue in China.展开更多
Bleeding is a clinical characteristic of severe dengue and may be due to increased vascular permeability. However, the patho- genesis of severe dengue remains unclear. In this study, we showed that the Racl-microfilam...Bleeding is a clinical characteristic of severe dengue and may be due to increased vascular permeability. However, the patho- genesis of severe dengue remains unclear. In this study, we showed that the Racl-microfilament signal pathway was involved in the process of DENV serotype 2 （DENV2） infection in EAhy926 cells. DENV2 infection induced dynamic changes in actin organization, and treatment with Cytochalasin D or Jasplakinolide disrupted microfilament dynamics, reduced DENV2 entry, and inhibited DENV2 assembly and maturation. Racl activities decreased during the early phase and gradually increased by the late phase of infection. Expression of the dominant-negative form of Racl promoted DENV2 entry but inhibited viral as- sembly, maturation and release. Our findings demonstrated that Racl plays an important role in the DENV2 life cycle by reg- ulating actin reorganization in EAhy926 cells. This finding provides further insight into the pathogenesis of severe dengue.展开更多
文摘目的通过实验室检测技术分析1名输入性发热病例的病毒性病原体,并判定其型别,为临床防治提供实验室依据。方法将采集到的血标本采用实时荧光定量聚合酶链式反应(Real time PCR)检测登革病毒核酸,使用通用引物和型特异性引物行逆转录-套式PCR扩增保守区域特异性核酸片段进行型别鉴定,通过登革病毒E基因扩增和序列测定对登革病毒进行亚型基因分型。结果病例血标本核酸经RT-PCR和逆转录-套式PCR方法鉴定为登革病毒2型(DENV-2),基因分类属于DENV-2全球型。结论该例输入性疑似登革热病例系DENV-2全球型引起。
基金supported by Guangzhou Science and Technology Program for Public Wellbeing(2014Y2-00185)the Special Program of National Science and Technology of China(2013ZX10004-805)the National Natural Science Foundation of China(81301491 and 31270974)
文摘Dengue has been well recognized as a global public health threat,but only sporadic epidemics and imported cases were reported in recent decades in China.Since July 2014,an unexpected large dengue outbreak has occurred in Guangdong province,China,resulting in more than 40000 patients including six deaths.To clarify and characterize the causative agent of this outbreak,the acute phase serum from a patient diagnosed with severe dengue was subjected to virus isolation and high-throughput sequencing(HTS).Traditional real-time RT-PCR and HTS with Ion Torrent PGM detected the presence of dengue virus serotype 2(DENV-2).A clinical DENV-2 isolate GZ05/2014 was obtained by culturing the patient serum in mosquito C6/36 cells.The complete genome of GZ05/2014 was determined and deposited in Gen Bank under the access number KP012546.Phylogenetic analysis based on the complete envelope gene showed that the newly DENV-2 isolate belonged to Cosmopolitan genotype and clustered closely with other Guangdong strains isolated in the past decade.No amino acid mutations that are obviously known to increase virulence or replication were identified throughout the genome of GZ05/2014.The high homology of Guangdong DENV-2 strains indicated the possibility of establishment of local DENV-2 circulation in Guangdong,China.These results help clarify the origin of this epidemic and predict the future status of dengue in China.
基金supported by the National Key Programs on Basic Research of China (2011CB504703)the National Natural Science Foundations of China (81301435, 81471957, 81271839, 81401676)Beijing Natural Science Foundation (7144194)
文摘Bleeding is a clinical characteristic of severe dengue and may be due to increased vascular permeability. However, the patho- genesis of severe dengue remains unclear. In this study, we showed that the Racl-microfilament signal pathway was involved in the process of DENV serotype 2 （DENV2） infection in EAhy926 cells. DENV2 infection induced dynamic changes in actin organization, and treatment with Cytochalasin D or Jasplakinolide disrupted microfilament dynamics, reduced DENV2 entry, and inhibited DENV2 assembly and maturation. Racl activities decreased during the early phase and gradually increased by the late phase of infection. Expression of the dominant-negative form of Racl promoted DENV2 entry but inhibited viral as- sembly, maturation and release. Our findings demonstrated that Racl plays an important role in the DENV2 life cycle by reg- ulating actin reorganization in EAhy926 cells. This finding provides further insight into the pathogenesis of severe dengue.
