采用基因分型测序(GBS)技术对堇叶紫金牛[Ardisia violacea(T.Suzuki)W.Z.Fang et K.Yao]13个野生居群77份样本进行单核苷酸多态性(SNP)位点挖掘,在此基础上,对13个居群77份样本的遗传多样性、系统发育树、亲缘关系等进行分析。结果表明...采用基因分型测序(GBS)技术对堇叶紫金牛[Ardisia violacea(T.Suzuki)W.Z.Fang et K.Yao]13个野生居群77份样本进行单核苷酸多态性(SNP)位点挖掘,在此基础上,对13个居群77份样本的遗传多样性、系统发育树、亲缘关系等进行分析。结果表明:共获得有效SNP位点246307个,每份样本检测到SNP位点1154~3789个。13个居群的观测杂合度为0.1569~0.4289,多态信息含量为0.0785~0.3244,核苷酸多样性指数为0.0002~0.0007,Tajima’s D值为0.2247~1.0936,Shannon’s多样性指数为0.2175~0.6649,表明堇叶紫金牛整体遗传多样性水平偏低。系统发育树、主成分分析和遗传结构分析结果显示77份样本可划分为6组。亲缘关系分析结果显示:居群内个体间的亲缘关系整体较近;居群间的亲缘关系与地理距离有一定的相关性。遗传分化和基因流分析结果显示:大部分居群间存在较高的遗传分化,各居群间存在一定程度的基因交流。综上所述,堇叶紫金牛13个居群的整体遗传多样性偏低,但居群间的遗传分化程度较高,这与居群间的地理距离较远、基因交流较少有关。建议优先保护安徽省黄山市祁门县牯牛降、浙江省舟山市定海区蔡家岙和浙江省宁波市象山县屠家园村3个遗传多样性较高的居群,并开展相关繁育工作以维持和扩大居群数量。展开更多
Introduction: Maternal asymptomatic colonization with GBS (Group-B Streptococcus) has become a major cause of sepsis, meningitis and encephalopathy in neonates alongside premature births, stillbirths and post-natal in...Introduction: Maternal asymptomatic colonization with GBS (Group-B Streptococcus) has become a major cause of sepsis, meningitis and encephalopathy in neonates alongside premature births, stillbirths and post-natal infections. Routine screening of pregnant women for GBS carriage and antimicrobial susceptibility are therefore necessary. This study was aimed at evaluating the prevalence, antimicrobial susceptibility pattern and factors associated with GBS colonization in pregnant women at the Regional Hospital Bamenda (RHB). Materials and Methods: Vaginal and rectal swab samples were collected from 121 pregnant women in the 3<sup>rd</sup> trimester at the RHB from December 2017 to May 2018. Sociodemographic, obstetric and neonatal history and some clinical parameters were obtained through a questionnaire approach. Cultures for the isolation and identification of GBS from the samples were done and grouping as well as susceptibility testing of GBS isolates was done. Results: The colonisation rates were 5.8% (7), 1.7% (2) and 5.8% (7) for rectal, vaginal and concomitant recto-vaginal carriage. GBS was isolated in the vagina/rectum of 16 participants (13.2% prevalence). Of the 16 GBS strains used for in vitro susceptibility test, no resistance to ampicillin, oxacillin, amoxicillin-clavulanate, ceftriaxone, erythromycin, imipenem, aztreonam and clindamycin was recorded. 6.3% (1) of the strains had intermediate susceptibility to ampicillin and amoxicillin-clavulanic acid. Of the isolates examined, 37.5% (6), and 12.5% (2) were respectively sensitive to gentamycin and levofloxacin. Maternal overweight, HIV positive status, history of PROM and spontaneous abortion, presence of Gardnerella vaginalis and Candida albicans had a high rate of GBS colonization but only HIV positive status had a statistical significance (p = 0.01). Other microbes isolated were Gardnerella vaginalis (55.4%, 67), Candida albicans (40.5%, 49), and Candida spp (12.4%, 15). Conclusion: GBS prevalence was 13.2%. GBS had decreased susceptibility to some antibiotics. Only HIV positive status was significantly associated with GBS colonization.展开更多
为构建多鳞[鱼喜](Sillago sihama)遗传连锁图谱并鉴定生长等重要经济性状数量性状位点(QTL),实验通过基因分型测序(GBS)技术对163个多鳞[鱼喜]个体(2个亲本和161个全同胞家系F1代)进行测序及标记分型,并通过复合区间定位法对该物种的...为构建多鳞[鱼喜](Sillago sihama)遗传连锁图谱并鉴定生长等重要经济性状数量性状位点(QTL),实验通过基因分型测序(GBS)技术对163个多鳞[鱼喜]个体(2个亲本和161个全同胞家系F1代)进行测序及标记分型,并通过复合区间定位法对该物种的体重、体高、体厚、眼径、体长和背鳍前长6个生长性状进行QTL定位分析。结果显示,多鳞[鱼喜]首张高密度遗传连锁图谱全长2 154.803 c M,标记间平均遗传距离0.455 c M,共有4 735个SNP标记分配到24个连锁群。QTL定位分析结果发现在6个生长性状中共检测到20个生长显著相关QTL位点,分布在8个连锁群上,单个QTL的LOD值范围为3.02~4.23,可解释的表型变异范围为0.14%~8.42%。其中,在连锁群LG08聚集了8个生长性状显著相关的QTL。通过对候选QTL区间内的基因进行功能注释,共筛选到了19个潜在生长调控相关基因,包含igf1、igf2、sstr5、sst1a、tgfbr2、gas1、igfals、gfg6、gfg20、bmp7、kdm5c、tti1以及rbm10等。实验获得的遗传标记及相关候选基因是多鳞[鱼喜]生长相关性状标记辅助选择(MAS)的有用基因资源,为进一步研究鱼类生长调控机制提供了更多的理论依据。展开更多
文摘采用基因分型测序(GBS)技术对堇叶紫金牛[Ardisia violacea(T.Suzuki)W.Z.Fang et K.Yao]13个野生居群77份样本进行单核苷酸多态性(SNP)位点挖掘,在此基础上,对13个居群77份样本的遗传多样性、系统发育树、亲缘关系等进行分析。结果表明:共获得有效SNP位点246307个,每份样本检测到SNP位点1154~3789个。13个居群的观测杂合度为0.1569~0.4289,多态信息含量为0.0785~0.3244,核苷酸多样性指数为0.0002~0.0007,Tajima’s D值为0.2247~1.0936,Shannon’s多样性指数为0.2175~0.6649,表明堇叶紫金牛整体遗传多样性水平偏低。系统发育树、主成分分析和遗传结构分析结果显示77份样本可划分为6组。亲缘关系分析结果显示:居群内个体间的亲缘关系整体较近;居群间的亲缘关系与地理距离有一定的相关性。遗传分化和基因流分析结果显示:大部分居群间存在较高的遗传分化,各居群间存在一定程度的基因交流。综上所述,堇叶紫金牛13个居群的整体遗传多样性偏低,但居群间的遗传分化程度较高,这与居群间的地理距离较远、基因交流较少有关。建议优先保护安徽省黄山市祁门县牯牛降、浙江省舟山市定海区蔡家岙和浙江省宁波市象山县屠家园村3个遗传多样性较高的居群,并开展相关繁育工作以维持和扩大居群数量。
文摘Introduction: Maternal asymptomatic colonization with GBS (Group-B Streptococcus) has become a major cause of sepsis, meningitis and encephalopathy in neonates alongside premature births, stillbirths and post-natal infections. Routine screening of pregnant women for GBS carriage and antimicrobial susceptibility are therefore necessary. This study was aimed at evaluating the prevalence, antimicrobial susceptibility pattern and factors associated with GBS colonization in pregnant women at the Regional Hospital Bamenda (RHB). Materials and Methods: Vaginal and rectal swab samples were collected from 121 pregnant women in the 3<sup>rd</sup> trimester at the RHB from December 2017 to May 2018. Sociodemographic, obstetric and neonatal history and some clinical parameters were obtained through a questionnaire approach. Cultures for the isolation and identification of GBS from the samples were done and grouping as well as susceptibility testing of GBS isolates was done. Results: The colonisation rates were 5.8% (7), 1.7% (2) and 5.8% (7) for rectal, vaginal and concomitant recto-vaginal carriage. GBS was isolated in the vagina/rectum of 16 participants (13.2% prevalence). Of the 16 GBS strains used for in vitro susceptibility test, no resistance to ampicillin, oxacillin, amoxicillin-clavulanate, ceftriaxone, erythromycin, imipenem, aztreonam and clindamycin was recorded. 6.3% (1) of the strains had intermediate susceptibility to ampicillin and amoxicillin-clavulanic acid. Of the isolates examined, 37.5% (6), and 12.5% (2) were respectively sensitive to gentamycin and levofloxacin. Maternal overweight, HIV positive status, history of PROM and spontaneous abortion, presence of Gardnerella vaginalis and Candida albicans had a high rate of GBS colonization but only HIV positive status had a statistical significance (p = 0.01). Other microbes isolated were Gardnerella vaginalis (55.4%, 67), Candida albicans (40.5%, 49), and Candida spp (12.4%, 15). Conclusion: GBS prevalence was 13.2%. GBS had decreased susceptibility to some antibiotics. Only HIV positive status was significantly associated with GBS colonization.
文摘为构建多鳞[鱼喜](Sillago sihama)遗传连锁图谱并鉴定生长等重要经济性状数量性状位点(QTL),实验通过基因分型测序(GBS)技术对163个多鳞[鱼喜]个体(2个亲本和161个全同胞家系F1代)进行测序及标记分型,并通过复合区间定位法对该物种的体重、体高、体厚、眼径、体长和背鳍前长6个生长性状进行QTL定位分析。结果显示,多鳞[鱼喜]首张高密度遗传连锁图谱全长2 154.803 c M,标记间平均遗传距离0.455 c M,共有4 735个SNP标记分配到24个连锁群。QTL定位分析结果发现在6个生长性状中共检测到20个生长显著相关QTL位点,分布在8个连锁群上,单个QTL的LOD值范围为3.02~4.23,可解释的表型变异范围为0.14%~8.42%。其中,在连锁群LG08聚集了8个生长性状显著相关的QTL。通过对候选QTL区间内的基因进行功能注释,共筛选到了19个潜在生长调控相关基因,包含igf1、igf2、sstr5、sst1a、tgfbr2、gas1、igfals、gfg6、gfg20、bmp7、kdm5c、tti1以及rbm10等。实验获得的遗传标记及相关候选基因是多鳞[鱼喜]生长相关性状标记辅助选择(MAS)的有用基因资源,为进一步研究鱼类生长调控机制提供了更多的理论依据。
