通过实验室观察及Y型管选择性试验,对草地螟上的优势种寄蝇-伞裙追寄蝇Exorista civilis Rond.的寄主选择性进行了研究。从这6种供试寄主中筛选出优良繁蝇的替代寄主,为该蝇的大规模繁殖及应用奠定理论基础。试验结果表明:伞裙追寄蝇对...通过实验室观察及Y型管选择性试验,对草地螟上的优势种寄蝇-伞裙追寄蝇Exorista civilis Rond.的寄主选择性进行了研究。从这6种供试寄主中筛选出优良繁蝇的替代寄主,为该蝇的大规模繁殖及应用奠定理论基础。试验结果表明:伞裙追寄蝇对6种鳞翅目幼虫和幼虫粪便的趋性顺序相同,依次为草地螟>粘虫>斜纹夜蛾>甜菜夜蛾>玉米螟>苜蓿夜蛾;不同寄主的羽化率结果表明,粘虫的羽化率最高,为70.2%。伞裙追寄蝇对寄主的选择性行为可能与寄主昆虫的活跃程度和其释放的化学信息物质有关。展开更多
Background:Brazil has seen a great decline in malaria and the country is moving towards elimination.However,for eventual elimination,the control program needs efficient tools in order to monitor malaria exposure and t...Background:Brazil has seen a great decline in malaria and the country is moving towards elimination.However,for eventual elimination,the control program needs efficient tools in order to monitor malaria exposure and transmission.In this study,we aimed to evaluate whether seroprevalence to the circumsporozoite protein(CSP)is a good tool for monitoring the exposure to and/or evaluating the burden and distribution of Plasmodium species in the Brazilian Amazon.Methods:Cross-sectional surveys were conducted in a rural area of Porto Velho,Rondônia state.Parasite infection was detected by microscopy and polymerase chain reaction.Antibodies to the sporozoite CSP repeats of Plasmodium vivax,P.falciparum,and P.malariae(PvCS,PfCS,and PmCS)were detected using the enzyme-linked immunosorbent assay technique.Human leukocyte antigen(HLA)-DRB1 and DQB1 genes were typed using Luminex®xMAP®technology.Results:The prevalence of immunoglobulin G against P.vivax CSP peptide(62%)was higher than P.falciparum(49%)and P.malariae(46%)CSP peptide.Most of the studied individuals had antibodies to at least one of the three peptides(72%),34%had antibodies to all three peptides and 28%were non-responders.Although the majority of the population was not infected at the time of the survey,74.3%of parasite-negative individuals had antibodies to at least one of the CSPs.Importantly,among individuals carrying the haplotypes DRB1*04~DQB1*03,there was a significantly higher frequency of PfCS responders,and DRB1*16~DQB1*03 haplotype for PvCS and PfCS responders.In contrast,HLA-DRB1*01 and HLA-DQB1*05 allelic groups were associated with a lack of antibodies to P.vivax and P.falciparum CSP repeats,and the haplotype DRB1*01~DQB1*05 was also associated with non-responders,including non-responders to P.malariae.Conclusions:Our results show that in low transmission settings,naturally acquired antibody responses against the CSP repeats of P.vivax,P.falciparum,and P.malariae in a single cross-sectional study may not represent a valuable marker for monitoring recent malaria exposure,especially in an area with a high prevalence of P.vivax.Furthermore,HLA class II molecules play an important role in antibody response and require further study with a larger sample size.It will be of interest to consider HLA analysis when using serosurveillance to monitor malaria exposure among genetically diverse populations.展开更多
文摘通过实验室观察及Y型管选择性试验,对草地螟上的优势种寄蝇-伞裙追寄蝇Exorista civilis Rond.的寄主选择性进行了研究。从这6种供试寄主中筛选出优良繁蝇的替代寄主,为该蝇的大规模繁殖及应用奠定理论基础。试验结果表明:伞裙追寄蝇对6种鳞翅目幼虫和幼虫粪便的趋性顺序相同,依次为草地螟>粘虫>斜纹夜蛾>甜菜夜蛾>玉米螟>苜蓿夜蛾;不同寄主的羽化率结果表明,粘虫的羽化率最高,为70.2%。伞裙追寄蝇对寄主的选择性行为可能与寄主昆虫的活跃程度和其释放的化学信息物质有关。
基金This work was supported by grants from PRONEX Rede Malaria,Conselho Nacional de Pesquisa e Tecnologia(CNPq)(5555659/2009-7)Funda cao de AmparoàPesquisa do Rio de Janeiro(E-26/170.003/2010)+2 种基金JO-F is a recipient of research productivity fellowships from the CNPq(307659/2016-0)VAP is the recipient of a CNPq fellowship(142104/2014-0)The funders had no role in the study design,data collection and analysis,decision to publish,or preparation of the paper.
文摘Background:Brazil has seen a great decline in malaria and the country is moving towards elimination.However,for eventual elimination,the control program needs efficient tools in order to monitor malaria exposure and transmission.In this study,we aimed to evaluate whether seroprevalence to the circumsporozoite protein(CSP)is a good tool for monitoring the exposure to and/or evaluating the burden and distribution of Plasmodium species in the Brazilian Amazon.Methods:Cross-sectional surveys were conducted in a rural area of Porto Velho,Rondônia state.Parasite infection was detected by microscopy and polymerase chain reaction.Antibodies to the sporozoite CSP repeats of Plasmodium vivax,P.falciparum,and P.malariae(PvCS,PfCS,and PmCS)were detected using the enzyme-linked immunosorbent assay technique.Human leukocyte antigen(HLA)-DRB1 and DQB1 genes were typed using Luminex®xMAP®technology.Results:The prevalence of immunoglobulin G against P.vivax CSP peptide(62%)was higher than P.falciparum(49%)and P.malariae(46%)CSP peptide.Most of the studied individuals had antibodies to at least one of the three peptides(72%),34%had antibodies to all three peptides and 28%were non-responders.Although the majority of the population was not infected at the time of the survey,74.3%of parasite-negative individuals had antibodies to at least one of the CSPs.Importantly,among individuals carrying the haplotypes DRB1*04~DQB1*03,there was a significantly higher frequency of PfCS responders,and DRB1*16~DQB1*03 haplotype for PvCS and PfCS responders.In contrast,HLA-DRB1*01 and HLA-DQB1*05 allelic groups were associated with a lack of antibodies to P.vivax and P.falciparum CSP repeats,and the haplotype DRB1*01~DQB1*05 was also associated with non-responders,including non-responders to P.malariae.Conclusions:Our results show that in low transmission settings,naturally acquired antibody responses against the CSP repeats of P.vivax,P.falciparum,and P.malariae in a single cross-sectional study may not represent a valuable marker for monitoring recent malaria exposure,especially in an area with a high prevalence of P.vivax.Furthermore,HLA class II molecules play an important role in antibody response and require further study with a larger sample size.It will be of interest to consider HLA analysis when using serosurveillance to monitor malaria exposure among genetically diverse populations.
