水产动物肌肉中的脂肪酸组成可用于评价其种群遗传。本研究通过测定和比较辽河(LH)、黄河(HH)、长江(YZ)、瓯江(OJ)、闽江(MJ)和南流江(NLJ)水系野生绒螯蟹(Eriocheir sensu stricto)肌肉中的脂肪酸组成,进一步分析了6群体间的遗传多样...水产动物肌肉中的脂肪酸组成可用于评价其种群遗传。本研究通过测定和比较辽河(LH)、黄河(HH)、长江(YZ)、瓯江(OJ)、闽江(MJ)和南流江(NLJ)水系野生绒螯蟹(Eriocheir sensu stricto)肌肉中的脂肪酸组成,进一步分析了6群体间的遗传多样性和亲缘关系。结果显示:(1)在6水系群体中检测出26种脂肪酸,其中C20:5n3、C18:1n9、C22:6n3、C16:0、C20:4n6、C18:2n6和C18:0为主要种类,其总和占总脂肪酸的74%以上;(2)逐步判别分析法筛选出8种判别贡献较大的脂肪酸,分别是C17:0、C18:0、C20:0、C22:1n9、C18:3n3、C18:3n6、C20:2n6和C22:5n3,据此分别建立判别方程,综合判别准确率为98.33%;(3)聚类分析显示:OJ与MJ群体的欧氏距离最小, HH与YZ群体的欧氏距离比OJ与MJ群体的要大,NLJ群体与其他5个群体的欧氏距离相对最大;(4)6群体间脂肪酸含量的变异系数在2.99%—30.00%之间,遗传多样性指数变化幅度在3.2732—3.3204之间。综上,基于脂肪酸生物标记法表明6水系绒螯蟹群体遗传多样性指数均较高,脂肪酸可以有效鉴别6水系野生绒螯蟹种群,整体上南流江群体和其余5群体间相距最远;本研究结果可为绒螯蟹种质资源评价和开发利用等提供基础资料。展开更多
为探究麦田前茬作物玉米秸秆和水稻秸秆上中国小麦赤霉病菌的两个优势种Fusarium graminearum sensu stricto(F.graminearum)和F.asiaticum子囊壳形成和发育成熟过程的差异,分别选择3株F.graminearum菌株(SE81,3-ADON型;LcA-2,15-ADON型...为探究麦田前茬作物玉米秸秆和水稻秸秆上中国小麦赤霉病菌的两个优势种Fusarium graminearum sensu stricto(F.graminearum)和F.asiaticum子囊壳形成和发育成熟过程的差异,分别选择3株F.graminearum菌株(SE81,3-ADON型;LcA-2,15-ADON型;HX5-1,NIV型)和2株F.asiaticum菌株(M4A,3-ADON型;M31-2,NIV型),用其孢子悬浮液接种玉米秸秆和水稻秸秆,放置于花泥和地表两种环境条件下,比较接种不同菌株秸秆上子囊壳的形成和发育成熟情况及5个菌株对‘郑麦366’(高感小麦赤霉病品种)的致病力。结果表明:花泥环境下产生子囊壳的速度要快于地表,以玉米秸秆为载体子囊壳产生速度比水稻秸秆快且多数密度大,3个F.graminearum菌株(SE81、LcA-2和HX5-1)在同种秸秆相同环境下比2个F.asiaticum菌株(M4A和M31-2)产生子囊壳的速度快且子囊壳密度大。5个菌株在不同环境的不同秸秆上产生的子囊壳的成熟度均无规律,接种‘郑麦366’后其病情指数间有极显著差异(P<0.01),在花泥和地表的玉米秸秆和水稻秸秆上3次调查的子囊壳密度与‘郑麦366’的病情指数呈显著正相关,不同环境条件下的子囊壳产生速度(AUPGC)与‘郑麦366’的病情指数呈极显著正相关。本研究将为阐明F.graminearum和F.asiaticum在中国小麦赤霉病上表现区域性地理分布的原因提供参考依据。展开更多
Fusarium graminearum sensu stricto和F.asiaticum是中国主要的禾谷镰刀菌复合种(FGSC)成员,为了提高这2个种的鉴定效率,选取48个引起小麦赤霉病和玉米茎腐病的FGSC菌株,比较了系统发育谱系分析、PCR-RFLP(聚合酶链式反应-限制性片段...Fusarium graminearum sensu stricto和F.asiaticum是中国主要的禾谷镰刀菌复合种(FGSC)成员,为了提高这2个种的鉴定效率,选取48个引起小麦赤霉病和玉米茎腐病的FGSC菌株,比较了系统发育谱系分析、PCR-RFLP(聚合酶链式反应-限制性片段长度多态性)和多重PCR 3种分子鉴定方法。系统发育谱系分析首先扩增菌株的EF-1α和Tri101两个基因的部分序列,测序之后利用MEGA 6.06软件构建系统发育树,结果表明,有11个菌株与F.asiaticum聚在一起,37个菌株与F.graminearum sensu stricto聚为一枝,此法繁琐、复杂、成本高,但鉴定结果准确。PCR-RFLP基于组蛋白H3基因特殊的酶切位点,设计引物H3d StyⅠ/H3R1,通过PCR和酶切反应进行鉴定,电泳检测发现,有11个菌株为F.asiaticum,37个菌株为F.graminearum sensu stricto,该法工作量大且对操作过程要求高。多重PCR基于CYP51A基因设计特异引物Fa F/FaR和Fg F/FgR进行鉴定,电泳检测结果表明,有11个菌株为F.asiaticum,37个菌株为F.graminearum sensu stricto,此法操作简单、效率高。以上3种分子鉴定方法结果一致,但多重PCR方法具有快速、准确、高效的特点。展开更多
Objective Western blotting (WB;immunoblotting) is a widely used tool for the serodiagnosis of Lyme borreliosis (LB),but so far,no generally accepted criteria for its performance and interpretation have been establ...Objective Western blotting (WB;immunoblotting) is a widely used tool for the serodiagnosis of Lyme borreliosis (LB),but so far,no generally accepted criteria for its performance and interpretation have been established in China.The present study was designed to determine the criteria for standardized Western blot for the predominant species of Borrelia burgdorferi sensu lato in China,in which WB was produced with strain PD91 as the representative strain attributed to predominant genospecies Borrelia garinii of Borrelia burgdorferi sensu lato.Methods Approximately 13 bands between 14 and 100 kD were differentiated for strain PD91 by using Gel-Pro analysis software.In a study with 631 serum samples (taken from 127 patients with Lyme borreliosis and 504 controls),all observed bands were documented.To establish criteria for a positive WB result for strain PD91,receiver operating characteristic (ROC) curves were used.Results The following interpretation criteria were recommended:for IgG,at least one band of P83/100,P58,P39,P30,OspC,P17,P66,and OspA;for IgM,at least one band of P83/100,P58,OspA,P30,OspC,P17 or P41.In addition,syphilis,leptospirosis and other related diseases should be excluded when the positive band is P41 in IgM.For IgG criteria,the sensitivity is 73.2%,the specificity is 99.4% and Youden index is 0.726;for IgM criteria,the sensitivity is 50.6%,the specificity is 93.1% and Youden index is 0.437.Conclusion Standardization of WB assays is necessary for comparison of results from different laboratories.Moreover,the criteria of other genospecies of Borrelia burgdorferi sensu lato should be determined in the future to complete the criteria of WB for the diagnosis of the Lyme disease in China.展开更多
We describe a new species of the genus Megophrys sensu lato from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as ...We describe a new species of the genus Megophrys sensu lato from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as an independent lineage in Megophrys(Panophrys) clade. The new species is distinguished from its congeners by a combination of the following morphological characteristics:(1) small body size with SVL < 38.8 mm in male and SVL < 42.3 mm in female;(2) vomerine teeth absent;(3) tongue not notched behind;(4) a small horn-like tubercle at the edge of each upper eyelid;(5) tympanum distinctly visible, rounded;(6) two metacarpal tubercles in hand;(7) relative finger lengths: II < I < V < III;(8) toes with rudimentary webbing at bases;(9) heels overlapping when thighs are positioned at right angles to the body;(10) tibiotarsal articulation reaching the level between tympanum to eye when leg stretched forward;(11) an internal single subgular vocal sac in male;(12) in breeding male, the nuptial pads with black nuptial spines on the dorsal bases of the first and second fingers.展开更多
Helicobacter heilmannii sensu lato(H.heilmannii s.l.)is a group of gastric non-Helicobacter pylori Helicobacter species that are morphologically indistinguishable from each other.H.heilmannii s.l.infect the stomach of...Helicobacter heilmannii sensu lato(H.heilmannii s.l.)is a group of gastric non-Helicobacter pylori Helicobacter species that are morphologically indistinguishable from each other.H.heilmannii s.l.infect the stomach of several animals and may have zoonotic potential.Although the prevalence of these infections in humans is low,they are associated with gastric pathology,including mucosa-associated lymphoid tissue lymphoma,making them a significant health issue.Here,the taxonomy,epidemiology,microbiology,diagnosis,and treatment of these infections will be reviewed.The gastric pathology associated with H.heilmannii s.l.infections in humans will also be addressed.Finally,the features of the complete bacterial genomes available and studies on species-specific pathogenesis will be reviewed.The understanding of the mechanisms that underlie gastric disease development mediated by the different bacterial species that constitute H.heilmannii s.l.is essential for developing strategies for prevention and treatment of these infections.展开更多
A spiral bacterium (SH9), morphologically different from Helicobacter pylori (H. pylori), was found in a 62-year-old woman’s gastric mucosa. Gastroscopic examination revealed multiple gastric ulcers near t...A spiral bacterium (SH9), morphologically different from Helicobacter pylori (H. pylori), was found in a 62-year-old woman’s gastric mucosa. Gastroscopic examination revealed multiple gastric ulcers near the pyloric ring; mapping gastric biopsy showed mild mononuclear infiltration with large lymphoid follicles in the antrum, without corpus atrophy. Urea breath test and H. pylori culture were negative, but Giemsa staining of biopsies revealed tightly coiled bacteria that immunostained with anti-H. pylori antibody. Sequencing of SH9 16S rRNA and the partial urease A and B subunit genes showed that the former sequence had highest similarity (99%; 1302/1315 bp) to Helicobacter heilmannii (H. heilmannii) sensu stricto (H. heilmannii s.s.) BC1 obtained from a bobcat, while the latter sequence confirmed highest similarity (98.3%; 1467/1493 bp) to H. heilmannii s.s. HU2 obtained from a human. The patient was diagnosed with multiple gastric ulcers associated with H. heilmannii s.s. infection. After triple therapy (amoxicillin, clarithromycin, and lansoprazole) with regimen for eradicating H. pylori, gastroscopy showed ulcer improvement and no H. heilmannii s.s. upon biopsy.展开更多
Objective Human Lyme Borreliosis (LB), which is caused by Borrefia burgdorferi sensu lato (B. burgdorferi), has been identified as a major arthropod-borne infectious disease in China. We aimed to develop a multipl...Objective Human Lyme Borreliosis (LB), which is caused by Borrefia burgdorferi sensu lato (B. burgdorferi), has been identified as a major arthropod-borne infectious disease in China. We aimed to develop a multiple locus variable-number tandem repeat (VNTR) analysis (MLVA) assay for the genotyping of Borrelia burgdorJ:eri strains detected in China. Methods B. garinii PBi complete 904.246 kb chromosome and two plasmids (cp26 and Ip54) were screened by using Tandem Repeats Finder program for getting potential VNTR loci, the potential VNTR loci were analyzed and identified with PCR and the VNTR loci data were analyzed and MLVA clustering tree were constrcted by using the categorical coefficient and the unweighted pair-group method with arithmetic means (UPGMA). Results We identified 5 new VNTR loci through analyzing 47 potential VNTR loci. We used the MLVA protocol to analyse 101 B. burgdorferi strains detected in China and finally identified 51 unique genotypes in 4 major clusters including B. burgdorferi sensu stricto (B.b.s.s), B. garinii, B. a[zelii, and B. valaisiana, consistent with the current MLSA phylogeny studies. The allele numbers of VNTR-1, VNTR-2, VNTR-3, VNTR-4, and VNTR-5 were 7, 3, 9, 7, and 6. The Hunter-Gaston index (HGI) of five VNTR loci were 0.79, 0.22, 0.77, 0.71, and 0.67, respectively. The combined HGI of five VNTR loci was 0.96. Clustering of the strains of Xinjiang, Inner Mongolia and Heilongjiang was confirmed, and this situation was consistent with the close geographical distribution of those provinces. Conclusion The MLVA protocol esytablished in this study is easy and can show strains' phylogenetic relationships to distinguish the strains of Borrelia species. It is useful for further phylogenetic and epidemiological analyses of Borrelia strains.展开更多
The Odorrana schmackeri sensu la to is a group of cascade frogs that are widely distributed in southern China.However,their taxonomy has long been unresolved and several cryptic species have been reported in the past ...The Odorrana schmackeri sensu la to is a group of cascade frogs that are widely distributed in southern China.However,their taxonomy has long been unresolved and several cryptic species have been reported in the past decade.Previous analyses revealed the existence of three sympatrie species(i.c,O.schmackeri,O.hejiangensis and O.sp2) at the type locality of O.schmackeri(Gaojiayan Town,Yichang City,Hubei Province,China).However,the lack of an original description for the holotype specimen(SMF6241) of O.schmackeri poses a confusing and controversial problem in species nomination within this group.Here,we reevaluate the taxonomic affinities of SMF6241 and examine the distinctness of O.sp2 based on specimens from the type locality.We use integrative approaches that combine morphology with 10 microsatellite loci and bioacoustics.Canonical discriminant analysis of morphological characteristics revealed three distinct groupings(i.e.,O.schmackeri,O.hejiangensis and O.sp2) and attributed SMF6241 to O.schmackeri.Genetic clustering analysis of nuclear DNA also identified three corresponding clusters.In addition,analysis of interspecific variation in morphometrics and acoustics showed divergence between O.sp2 and its sympatric congeners.All lines of evidence from morphological,molecular and bioacoustic approaches suggest the species status of O.sp2,namely Odorrana ichangensis Chen,sp.nov.Overall,this study resolves the taxonomic assignment of the holotype of O.schmackeri and provides an example for species delimitation using integrative approaches.展开更多
A set of universal loop-mediated isothermal amplification (LAMP) primers targeting the flo gene was designed to detect Borrelia burgdorferi sensu lato (B. burgdorferi s.I.) in human samples. The sensitivity of LAM...A set of universal loop-mediated isothermal amplification (LAMP) primers targeting the flo gene was designed to detect Borrelia burgdorferi sensu lato (B. burgdorferi s.I.) in human samples. The sensitivity of LAMP was 20 copies/reaction, and the assay did not detect false positives among 11 other related bacteria. A positive LAMP result was obtained for 9 of the 24 confirmed cases and for 12 of 94 suspected cases. The positive rate of LAMP was the same as that of nested PCR. The LAMP is a useful diagnostic method that can be developed for rapid detection of B. burgdorferi s.I. in human sera. Combination of the LAMP and nested PCR was more sensitive for detecting B. burgdorferi s.I. in human serum samples.展开更多
Recent advances in molecular biology make it possible to sequence not only genes or genomes,but also to understand codon dynamics.For the organelle genes of these organisms,a small set of preferred codons are used for...Recent advances in molecular biology make it possible to sequence not only genes or genomes,but also to understand codon dynamics.For the organelle genes of these organisms,a small set of preferred codons are used for encoding proteins.For the first time,this paper treats the divergence of synonymous codon usage and its bias in the rbcL gene within the Laurencia complex of red algae.We observed that the synonymous codon preference biases in rbcL are large and differ among species.A clear distinction in codon usage between genera is evident:the genera Dasya and Delesseria use a set that fluctuated between 53 and 58 codons.Whereas,in the genera Ceramium,Chondrophycus,Chlamydomonas,Chlorella,Laurencia s.s,Osmundea,and Palisada codon usage indicates a higher restriction fluctuating between 40 to 51 codons.Laurencia complex genera and other representative algae showed a defined composition pattern,with lower percentage values of NNC/G(7-24.9%).Dasya and Delesseria showed a selective pattern tendency because of high percentage values of NNC/G(54-55%).The estimated codon bias parameters were tested to infer systematic relationships and match suitable codons with the NNC/G codon percentages.Cluster analysis based on Codon Usage supports phylogenetic relationships between Chondrophycus,Palisada,Laurencia,Osmundea,and Yuzurua species.展开更多
文摘水产动物肌肉中的脂肪酸组成可用于评价其种群遗传。本研究通过测定和比较辽河(LH)、黄河(HH)、长江(YZ)、瓯江(OJ)、闽江(MJ)和南流江(NLJ)水系野生绒螯蟹(Eriocheir sensu stricto)肌肉中的脂肪酸组成,进一步分析了6群体间的遗传多样性和亲缘关系。结果显示:(1)在6水系群体中检测出26种脂肪酸,其中C20:5n3、C18:1n9、C22:6n3、C16:0、C20:4n6、C18:2n6和C18:0为主要种类,其总和占总脂肪酸的74%以上;(2)逐步判别分析法筛选出8种判别贡献较大的脂肪酸,分别是C17:0、C18:0、C20:0、C22:1n9、C18:3n3、C18:3n6、C20:2n6和C22:5n3,据此分别建立判别方程,综合判别准确率为98.33%;(3)聚类分析显示:OJ与MJ群体的欧氏距离最小, HH与YZ群体的欧氏距离比OJ与MJ群体的要大,NLJ群体与其他5个群体的欧氏距离相对最大;(4)6群体间脂肪酸含量的变异系数在2.99%—30.00%之间,遗传多样性指数变化幅度在3.2732—3.3204之间。综上,基于脂肪酸生物标记法表明6水系绒螯蟹群体遗传多样性指数均较高,脂肪酸可以有效鉴别6水系野生绒螯蟹种群,整体上南流江群体和其余5群体间相距最远;本研究结果可为绒螯蟹种质资源评价和开发利用等提供基础资料。
文摘为探究麦田前茬作物玉米秸秆和水稻秸秆上中国小麦赤霉病菌的两个优势种Fusarium graminearum sensu stricto(F.graminearum)和F.asiaticum子囊壳形成和发育成熟过程的差异,分别选择3株F.graminearum菌株(SE81,3-ADON型;LcA-2,15-ADON型;HX5-1,NIV型)和2株F.asiaticum菌株(M4A,3-ADON型;M31-2,NIV型),用其孢子悬浮液接种玉米秸秆和水稻秸秆,放置于花泥和地表两种环境条件下,比较接种不同菌株秸秆上子囊壳的形成和发育成熟情况及5个菌株对‘郑麦366’(高感小麦赤霉病品种)的致病力。结果表明:花泥环境下产生子囊壳的速度要快于地表,以玉米秸秆为载体子囊壳产生速度比水稻秸秆快且多数密度大,3个F.graminearum菌株(SE81、LcA-2和HX5-1)在同种秸秆相同环境下比2个F.asiaticum菌株(M4A和M31-2)产生子囊壳的速度快且子囊壳密度大。5个菌株在不同环境的不同秸秆上产生的子囊壳的成熟度均无规律,接种‘郑麦366’后其病情指数间有极显著差异(P<0.01),在花泥和地表的玉米秸秆和水稻秸秆上3次调查的子囊壳密度与‘郑麦366’的病情指数呈显著正相关,不同环境条件下的子囊壳产生速度(AUPGC)与‘郑麦366’的病情指数呈极显著正相关。本研究将为阐明F.graminearum和F.asiaticum在中国小麦赤霉病上表现区域性地理分布的原因提供参考依据。
文摘Fusarium graminearum sensu stricto和F.asiaticum是中国主要的禾谷镰刀菌复合种(FGSC)成员,为了提高这2个种的鉴定效率,选取48个引起小麦赤霉病和玉米茎腐病的FGSC菌株,比较了系统发育谱系分析、PCR-RFLP(聚合酶链式反应-限制性片段长度多态性)和多重PCR 3种分子鉴定方法。系统发育谱系分析首先扩增菌株的EF-1α和Tri101两个基因的部分序列,测序之后利用MEGA 6.06软件构建系统发育树,结果表明,有11个菌株与F.asiaticum聚在一起,37个菌株与F.graminearum sensu stricto聚为一枝,此法繁琐、复杂、成本高,但鉴定结果准确。PCR-RFLP基于组蛋白H3基因特殊的酶切位点,设计引物H3d StyⅠ/H3R1,通过PCR和酶切反应进行鉴定,电泳检测发现,有11个菌株为F.asiaticum,37个菌株为F.graminearum sensu stricto,该法工作量大且对操作过程要求高。多重PCR基于CYP51A基因设计特异引物Fa F/FaR和Fg F/FgR进行鉴定,电泳检测结果表明,有11个菌株为F.asiaticum,37个菌株为F.graminearum sensu stricto,此法操作简单、效率高。以上3种分子鉴定方法结果一致,但多重PCR方法具有快速、准确、高效的特点。
基金supported by the "Tenth Five-Year Plan" project of research on the specific diagnosis method for the Lyme disease. 2001BA705B07
文摘Objective Western blotting (WB;immunoblotting) is a widely used tool for the serodiagnosis of Lyme borreliosis (LB),but so far,no generally accepted criteria for its performance and interpretation have been established in China.The present study was designed to determine the criteria for standardized Western blot for the predominant species of Borrelia burgdorferi sensu lato in China,in which WB was produced with strain PD91 as the representative strain attributed to predominant genospecies Borrelia garinii of Borrelia burgdorferi sensu lato.Methods Approximately 13 bands between 14 and 100 kD were differentiated for strain PD91 by using Gel-Pro analysis software.In a study with 631 serum samples (taken from 127 patients with Lyme borreliosis and 504 controls),all observed bands were documented.To establish criteria for a positive WB result for strain PD91,receiver operating characteristic (ROC) curves were used.Results The following interpretation criteria were recommended:for IgG,at least one band of P83/100,P58,P39,P30,OspC,P17,P66,and OspA;for IgM,at least one band of P83/100,P58,OspA,P30,OspC,P17 or P41.In addition,syphilis,leptospirosis and other related diseases should be excluded when the positive band is P41 in IgM.For IgG criteria,the sensitivity is 73.2%,the specificity is 99.4% and Youden index is 0.726;for IgM criteria,the sensitivity is 50.6%,the specificity is 93.1% and Youden index is 0.437.Conclusion Standardization of WB assays is necessary for comparison of results from different laboratories.Moreover,the criteria of other genospecies of Borrelia burgdorferi sensu lato should be determined in the future to complete the criteria of WB for the diagnosis of the Lyme disease in China.
基金Collections in field were permitted by Administration of Leigong Mountain Nantioanl Nature Reserve (No. LGS20040348)approved by the animal ethical committee of Chengdu Institute of Biology, Chinese Academy of Sciences, and animal experiments were carried out following the institutional guidelines (No. 2017CIBAEC0344)+4 种基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB31000000)National Natural Sciences Foundation of China (NSFC31201702) Biodiversity Conservation Key Laboratory of Guizhou province Education Department, Guiyang College, The laboratory on biodiversity conservation and applied ecology of Guiyang college, Ocean Park Conservation Foundation of Hong Kong (No. PR 1030001252)Biodiversity Conservation Program of Ministry of Ecology and Environment of China (#2110404)Guizhou Provincial Department of Education Youth Science and Technology Talents Growth Project (Nos. KY[2018]455, KY[2018]468 and KY[2018]453)
文摘We describe a new species of the genus Megophrys sensu lato from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as an independent lineage in Megophrys(Panophrys) clade. The new species is distinguished from its congeners by a combination of the following morphological characteristics:(1) small body size with SVL < 38.8 mm in male and SVL < 42.3 mm in female;(2) vomerine teeth absent;(3) tongue not notched behind;(4) a small horn-like tubercle at the edge of each upper eyelid;(5) tympanum distinctly visible, rounded;(6) two metacarpal tubercles in hand;(7) relative finger lengths: II < I < V < III;(8) toes with rudimentary webbing at bases;(9) heels overlapping when thighs are positioned at right angles to the body;(10) tibiotarsal articulation reaching the level between tympanum to eye when leg stretched forward;(11) an internal single subgular vocal sac in male;(12) in breeding male, the nuptial pads with black nuptial spines on the dorsal bases of the first and second fingers.
文摘Helicobacter heilmannii sensu lato(H.heilmannii s.l.)is a group of gastric non-Helicobacter pylori Helicobacter species that are morphologically indistinguishable from each other.H.heilmannii s.l.infect the stomach of several animals and may have zoonotic potential.Although the prevalence of these infections in humans is low,they are associated with gastric pathology,including mucosa-associated lymphoid tissue lymphoma,making them a significant health issue.Here,the taxonomy,epidemiology,microbiology,diagnosis,and treatment of these infections will be reviewed.The gastric pathology associated with H.heilmannii s.l.infections in humans will also be addressed.Finally,the features of the complete bacterial genomes available and studies on species-specific pathogenesis will be reviewed.The understanding of the mechanisms that underlie gastric disease development mediated by the different bacterial species that constitute H.heilmannii s.l.is essential for developing strategies for prevention and treatment of these infections.
基金Supported by A Grant-in-Aid for Scientific Research C-20590564 from the Ministry of Education,Culture,Sports,Science and Technology,Japan,to Ota H
文摘A spiral bacterium (SH9), morphologically different from Helicobacter pylori (H. pylori), was found in a 62-year-old woman’s gastric mucosa. Gastroscopic examination revealed multiple gastric ulcers near the pyloric ring; mapping gastric biopsy showed mild mononuclear infiltration with large lymphoid follicles in the antrum, without corpus atrophy. Urea breath test and H. pylori culture were negative, but Giemsa staining of biopsies revealed tightly coiled bacteria that immunostained with anti-H. pylori antibody. Sequencing of SH9 16S rRNA and the partial urease A and B subunit genes showed that the former sequence had highest similarity (99%; 1302/1315 bp) to Helicobacter heilmannii (H. heilmannii) sensu stricto (H. heilmannii s.s.) BC1 obtained from a bobcat, while the latter sequence confirmed highest similarity (98.3%; 1467/1493 bp) to H. heilmannii s.s. HU2 obtained from a human. The patient was diagnosed with multiple gastric ulcers associated with H. heilmannii s.s. infection. After triple therapy (amoxicillin, clarithromycin, and lansoprazole) with regimen for eradicating H. pylori, gastroscopy showed ulcer improvement and no H. heilmannii s.s. upon biopsy.
基金supported by Natural Science foundation(Grant No.31100105)China Mega-Project for Infectious Disease(2012ZX10004-215 and 2013ZX10004221)
文摘Objective Human Lyme Borreliosis (LB), which is caused by Borrefia burgdorferi sensu lato (B. burgdorferi), has been identified as a major arthropod-borne infectious disease in China. We aimed to develop a multiple locus variable-number tandem repeat (VNTR) analysis (MLVA) assay for the genotyping of Borrelia burgdorJ:eri strains detected in China. Methods B. garinii PBi complete 904.246 kb chromosome and two plasmids (cp26 and Ip54) were screened by using Tandem Repeats Finder program for getting potential VNTR loci, the potential VNTR loci were analyzed and identified with PCR and the VNTR loci data were analyzed and MLVA clustering tree were constrcted by using the categorical coefficient and the unweighted pair-group method with arithmetic means (UPGMA). Results We identified 5 new VNTR loci through analyzing 47 potential VNTR loci. We used the MLVA protocol to analyse 101 B. burgdorferi strains detected in China and finally identified 51 unique genotypes in 4 major clusters including B. burgdorferi sensu stricto (B.b.s.s), B. garinii, B. a[zelii, and B. valaisiana, consistent with the current MLSA phylogeny studies. The allele numbers of VNTR-1, VNTR-2, VNTR-3, VNTR-4, and VNTR-5 were 7, 3, 9, 7, and 6. The Hunter-Gaston index (HGI) of five VNTR loci were 0.79, 0.22, 0.77, 0.71, and 0.67, respectively. The combined HGI of five VNTR loci was 0.96. Clustering of the strains of Xinjiang, Inner Mongolia and Heilongjiang was confirmed, and this situation was consistent with the close geographical distribution of those provinces. Conclusion The MLVA protocol esytablished in this study is easy and can show strains' phylogenetic relationships to distinguish the strains of Borrelia species. It is useful for further phylogenetic and epidemiological analyses of Borrelia strains.
基金supported by the National Natural Sciences Foundation of China (NSFC-31872220, 31572245, 31372164)。
文摘The Odorrana schmackeri sensu la to is a group of cascade frogs that are widely distributed in southern China.However,their taxonomy has long been unresolved and several cryptic species have been reported in the past decade.Previous analyses revealed the existence of three sympatrie species(i.c,O.schmackeri,O.hejiangensis and O.sp2) at the type locality of O.schmackeri(Gaojiayan Town,Yichang City,Hubei Province,China).However,the lack of an original description for the holotype specimen(SMF6241) of O.schmackeri poses a confusing and controversial problem in species nomination within this group.Here,we reevaluate the taxonomic affinities of SMF6241 and examine the distinctness of O.sp2 based on specimens from the type locality.We use integrative approaches that combine morphology with 10 microsatellite loci and bioacoustics.Canonical discriminant analysis of morphological characteristics revealed three distinct groupings(i.e.,O.schmackeri,O.hejiangensis and O.sp2) and attributed SMF6241 to O.schmackeri.Genetic clustering analysis of nuclear DNA also identified three corresponding clusters.In addition,analysis of interspecific variation in morphometrics and acoustics showed divergence between O.sp2 and its sympatric congeners.All lines of evidence from morphological,molecular and bioacoustic approaches suggest the species status of O.sp2,namely Odorrana ichangensis Chen,sp.nov.Overall,this study resolves the taxonomic assignment of the holotype of O.schmackeri and provides an example for species delimitation using integrative approaches.
基金funded by the National Key Science and Technology Projects of China(2012ZX10004219 and 2013ZX10004001)
文摘A set of universal loop-mediated isothermal amplification (LAMP) primers targeting the flo gene was designed to detect Borrelia burgdorferi sensu lato (B. burgdorferi s.I.) in human samples. The sensitivity of LAMP was 20 copies/reaction, and the assay did not detect false positives among 11 other related bacteria. A positive LAMP result was obtained for 9 of the 24 confirmed cases and for 12 of 94 suspected cases. The positive rate of LAMP was the same as that of nested PCR. The LAMP is a useful diagnostic method that can be developed for rapid detection of B. burgdorferi s.I. in human sera. Combination of the LAMP and nested PCR was more sensitive for detecting B. burgdorferi s.I. in human serum samples.
基金UAM-I-117“Macroalgas Marinas y Salobres”of the CBS-UAMI Division,and the Ministry of Science and Innovation of the Spanish Government(CGL2010-14881).
文摘Recent advances in molecular biology make it possible to sequence not only genes or genomes,but also to understand codon dynamics.For the organelle genes of these organisms,a small set of preferred codons are used for encoding proteins.For the first time,this paper treats the divergence of synonymous codon usage and its bias in the rbcL gene within the Laurencia complex of red algae.We observed that the synonymous codon preference biases in rbcL are large and differ among species.A clear distinction in codon usage between genera is evident:the genera Dasya and Delesseria use a set that fluctuated between 53 and 58 codons.Whereas,in the genera Ceramium,Chondrophycus,Chlamydomonas,Chlorella,Laurencia s.s,Osmundea,and Palisada codon usage indicates a higher restriction fluctuating between 40 to 51 codons.Laurencia complex genera and other representative algae showed a defined composition pattern,with lower percentage values of NNC/G(7-24.9%).Dasya and Delesseria showed a selective pattern tendency because of high percentage values of NNC/G(54-55%).The estimated codon bias parameters were tested to infer systematic relationships and match suitable codons with the NNC/G codon percentages.Cluster analysis based on Codon Usage supports phylogenetic relationships between Chondrophycus,Palisada,Laurencia,Osmundea,and Yuzurua species.