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Cedrol ameliorates ulcerative colitis via myeloid differentiation factor 2-mediated inflammation suppression,with barrier restoration and microbiota modulation
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作者 Yi-Qing Zhao Yu Zhang +2 位作者 Yan Qin Rui-Ya Zhang Jun-Ping Wang 《World Journal of Gastroenterology》 2026年第2期135-151,共17页
BACKGROUND Ulcerative colitis(UC)is a chronic and treatment-resistant disorder requiring potent therapeutics that are effective and safe.Cedrol(CE)is a bioactive natural product present in many traditional Chinese med... BACKGROUND Ulcerative colitis(UC)is a chronic and treatment-resistant disorder requiring potent therapeutics that are effective and safe.Cedrol(CE)is a bioactive natural product present in many traditional Chinese medicines.It is known for its suppression of inflammation and mitigation of oxidative stress.Its therapeutic efficacy and mechanistic underpinnings in UC remain uncharacterized.AIM To investigate the therapeutic potential and mechanisms of CE in UC.METHODS The anti-inflammatory activity and intestinal barrier-repairing effects of CE were assessed in a dextran sulfate sodium-induced murine colitis model.Network pharmacology was employed to predict potential targets and pathways.Then molecular docking and dynamics simulations were utilized to confirm a stable interaction between CE and the toll-like receptor 4(TLR4)/myeloid differentiation factor 2(MD2)complex.The anti-inflammatory mechanisms were further verified using in vitro assays.Additionally,the gut microbiota composition was analyzed via 16S rRNA gene sequencing.RESULTS CE significantly alleviated colitis symptoms,mitigated histopathological damage,and suppressed inflammation.Moreover,CE restored intestinal barrier integrity by enhancing mucus secretion and upregulating tight junction proteins(zonula occludens 1,occludin,claudin-1).Mechanistically,CE stably bound to MD2,inhibiting lipopolysaccharide-induced TLR4 signaling in RAW264.7 cells.This led to suppression of the downstream mitogen-activated protein kinase and nuclear factor kappa B signaling pathways,downregulating the expression of tumor necrosis factor-alpha,interleukin-1β,and interleukin-6.Gut microbiota analysis revealed that CE reversed dextran sulfate sodium-induced dysbiosis with significant enrichment of butyrogenic Christensenella minuta.CONCLUSION CE acted on MD2 to suppress proinflammatory cascades,promoting mucosal barrier reconstitution and microbiota remodeling and supporting its therapeutic use in UC. 展开更多
关键词 CEDROL Ulcerative colitis Toll-like receptor 4 Myeloid differentiation factor 2 Signaling pathways Gut microbiota
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两个镍配合物的结构、抑菌活性及与DNA的相互作用
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作者 季甲 姚腾奇 +5 位作者 邓文钱 石文婧 吕璇 田琳 辛晓艳 侯银玲 《无机化学学报》 北大核心 2026年第1期78-86,共9页
通过原位反应,设计合成了2例配合物[Ni(HL_(1))_(2)]·CH_(3)CN·CH_(3)OH(1)和[Ni(L2)2](2),其中H_(2)L_(1)=2-羟基苯甲酸(6-甲氧基-吡啶-2-基亚甲基)-肼,HL2=4-溴-2-[(6-甲氧基吡啶-2-基亚甲基)-氨基]-苯酚。单晶X射线衍射分... 通过原位反应,设计合成了2例配合物[Ni(HL_(1))_(2)]·CH_(3)CN·CH_(3)OH(1)和[Ni(L2)2](2),其中H_(2)L_(1)=2-羟基苯甲酸(6-甲氧基-吡啶-2-基亚甲基)-肼,HL2=4-溴-2-[(6-甲氧基吡啶-2-基亚甲基)-氨基]-苯酚。单晶X射线衍射分析表明:配合物1和2均具有以二价镍离子为中心的单核零维结构。打孔抑菌圈实验数据表明,与单纯的过渡金属镍离子相比,配合物1和2表现出更强的抑菌活性。采用紫外可见光谱法、循环伏安法和荧光光谱法研究了配合物1和2与小牛胸腺DNA(CTDNA)之间的相互作用,结果表明2个配合物均通过插入作用模式与CTDNA结合。 展开更多
关键词 Ni配合物 原位合成 晶体结构 生物活性 dna相互作用
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基于环境DNA的河-湖水生态调查与评估研究进展
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作者 魏源送 蔡佳琳 +5 位作者 谢阳村 张耀方 程楷文 薛万来 魏明海 张俊亚 《环境科学学报》 北大核心 2026年第1期1-22,共22页
环境DNA(eDNA)技术通过分析环境样品中的遗传物质,为水生态监测与评估带来了革命性进展,实现了非侵入性、高灵敏度及多物种同步检测.本综述系统梳理并总结了近年来eDNA技术在河湖水生态调查与评估应用全链条—从eDNA信号的产生与环境行... 环境DNA(eDNA)技术通过分析环境样品中的遗传物质,为水生态监测与评估带来了革命性进展,实现了非侵入性、高灵敏度及多物种同步检测.本综述系统梳理并总结了近年来eDNA技术在河湖水生态调查与评估应用全链条—从eDNA信号的产生与环境行为到样本采集、实验分析、数据解读及模型应用的关键研究进展,并剖析了面临的核心科学问题与技术挑战.当前,eDNA技术在生物多样性评估、濒危物种追踪、外来种入侵预警及生态修复评价等方面已展现出显著应用潜力,但其可靠性与推广仍面临eDNA信号环境动态复杂、参考数据库不完整、引物通用性与特异性难以兼顾、以及生物信息分析流程标准化不足等挑战.区别于其它综述,本文不仅全面覆盖各环节的现状与瓶颈,更从标准化建设、技术方法革新、数据资源共享、多源信息融合及智能化决策支持等维度,前瞻性地展望了该领域未来的发展方向与系统性解决方案的构建框架,以期为科研工作者深入把握eDNA技术的最新进展与未来趋势提供参考,从而助力该领域的技术优化与标准化进程. 展开更多
关键词 环境dna(edna) 水生态系统 生物多样性监测 宏条形码 参考数据库 标准化
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DNA甲基化调控与植物响应逆境的表观调控机制的研究进展
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作者 金太成 李宇硕 +3 位作者 王伟妍 肖竹猗 于佳雪 杨丽萍 《吉林师范大学学报(自然科学版)》 2026年第1期89-94,共6页
植物逆境包括生物胁迫与非生物胁迫,其中,非生物胁迫涵盖盐胁迫、干旱胁迫、低温胁迫等类型,生物胁迫则包含细菌病、真菌病、病毒病等,二者均会严重影响作物的产量与品质.因此,开展植物与环境互作机制的研究显得尤为重要.植物脱氧核糖核... 植物逆境包括生物胁迫与非生物胁迫,其中,非生物胁迫涵盖盐胁迫、干旱胁迫、低温胁迫等类型,生物胁迫则包含细菌病、真菌病、病毒病等,二者均会严重影响作物的产量与品质.因此,开展植物与环境互作机制的研究显得尤为重要.植物脱氧核糖核酸(DNA)甲基化作为一种关键的表观遗传修饰途径,可通过调控植物基因表达,助力植物适应环境变化,进而增强植物应对逆境的能力.本文对植物表观遗传调控的相关内容进行了概述,具体涉及DNA甲基化、组蛋白修饰以及非编码核糖核酸(RNA)的调控等方面.重点介绍了DNA甲基化途径、DNA甲基化的功能作用、病毒与植物表观遗传调控的互作机制,以及DNA甲基化调控植物响应非生物胁迫的研究现状,旨在为植物响应逆境的表观遗传调控机制研究提供理论基础与重要参考依据. 展开更多
关键词 表观遗传调控 生物胁迫 非生物胁迫 dna甲基化
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自己“组装”DNA链置换计算机——人工智能和仿真软件支持下的跨学科学习案例
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作者 陈凯 《中国信息技术教育》 2026年第1期27-31,共5页
DNA链置换是实现分子逻辑门进而实现较复杂的DNA计算的一种方法,DNA计算问题天然具有跨学科特征,人工智能工具和仿真软件的支持,对学习者在实施相关跨学科学习过程中消除学科壁垒、降低认知负荷起到很大的作用。本文以构造2-4二进制解... DNA链置换是实现分子逻辑门进而实现较复杂的DNA计算的一种方法,DNA计算问题天然具有跨学科特征,人工智能工具和仿真软件的支持,对学习者在实施相关跨学科学习过程中消除学科壁垒、降低认知负荷起到很大的作用。本文以构造2-4二进制解码器为例,阐述和分析在当前已有技术支持下,生成式人工智能工具和仿真软件在DNA计算相关跨学科学习过程中可能发挥的作用、优势以及弱点。 展开更多
关键词 dna链置换 生成式人工智能 仿真软件
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mRNA expression and DNA methylation in three key genes involved in caste differentiation in female honeybees(Apis mellifera) 被引量:3
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作者 Xin-Liang SHAO Shao-Yu HE +3 位作者 Xin-Ying ZHUANG Ying FAN Ya-Hui LI Yong-Gang YAO 《Zoological Research》 CAS CSCD 北大核心 2014年第2期92-98,共7页
In honeybee (Apis mellifera) colonies, queens and workers are altemative forms of the adult female honeybee that develop from genetically identical zygotes but that depend on differential nourishment. Queens and wor... In honeybee (Apis mellifera) colonies, queens and workers are altemative forms of the adult female honeybee that develop from genetically identical zygotes but that depend on differential nourishment. Queens and workers display distinct morphologies, anatomies and behavior, better known as caste differentiation. Despite some basic insights, the exact mechanism responsible for this phenomenon, especially at the molecular level, remains unclear although some progress has been achieved. In this study, we examined mRNA levels of the TOR (target of rapamycin) and Dnmt3 (DNA methyltransferase 3) genes, closely related to caste differentiation in honeybees. We also investigated mRNA expression of the S6K (similar to RPS6-p70-protein kinase) gene linked closely to organismal growth and development in queen and worker larvae (1-day and 3-day old). Last, we investigated the methylation status of these three genes in corresponding castes. We found no difference in mRNA expression for the three genes between 1st instar queen and worker larvae; however, 3rd instar queen larvae had a higher level of TOR mRNA than worker larvae. Methylation levels of all three genes were lower in queen larvae than worker larvae but the differences were not statistically significant. These findings provide basic data for broadening our understanding of caste differentiation in female honeybees. 展开更多
关键词 Caste differentiation dna methylation dna methyltransferase 3 HONEYBEE Target of rapamycin
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DNA N^6-methyladenine demethylase ALKBH1 enhances osteogenic differentiation of human MSCs 被引量:7
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作者 Chenchen Zhou Yuting Liu +2 位作者 Xiaobing Li Jing Zou Shujuan Zou 《Bone Research》 SCIE CAS CSCD 2016年第3期174-182,共9页
ALKBH1 was recently discovered as a demethylase for DNA N6-methyladenine (N6-mA), a new epigenetic modification, and interacts with the core transcriptional pluripotency network of embryonic stem cells. However, the... ALKBH1 was recently discovered as a demethylase for DNA N6-methyladenine (N6-mA), a new epigenetic modification, and interacts with the core transcriptional pluripotency network of embryonic stem cells. However, the role of ALKBH1 and DNA N6-mA in regulating osteogenic differentiation is largely unknown. In this study, we demonstrated that the expression of ALKBH1 in human mesenchymal stem cells (MSCs) was upregulated during osteogenic induction. Knockdown of ALKBH1 increased the genomic DNA N6-mA levels and significantly reduced the expression of osteogenic-related genes, alkaline phosphatase activity, and mineralization. ALKBHl-depleted MSCs also exhibited a restricted capacity for bone formation in vivo. By contrast, the ectopic overexpression of ALKBH1 enhanced osteoblastic differentiation. Mechanically, we found that the depletion of ALKBH1 resulted in the accumulation of N6-mA on the promoter region of ATF4, which subsequently silenced ATF4 transcription. In addition, restoring the expression of ATP by adenovirus-mediated transduction successfully rescued osteogenic differentiation. Taken together, our results demonstrate that ALKBH1 is indispensable for the osteogenic differentiation of MSCs and indicate that DNA N6-mA modifications area new mechanism for the epigenetic regulation of stem cell differentiation. 展开更多
关键词 ATF Figure MSCS dna N~6-methyladenine demethylase ALKBH1 enhances osteogenic differentiation of human MSCs
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Differentiation of coral trout (Plectropomus leopardus) based on an analysis of morphology and complete mitochondrial DNA: Are cryptic species present? 被引量:2
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作者 CAI Xiaopeng QU Meng +4 位作者 DING Shaoxiong WANG Hangjun WANG Hongjie HU Luyi SU Yongquan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第6期40-46,共7页
Two morphotypes of Plectropomus leopardus have been identified; morphometric and meristic analyses show that there is no diagnostic difference between them. A difference in color pattern was the most ap- propriate phe... Two morphotypes of Plectropomus leopardus have been identified; morphometric and meristic analyses show that there is no diagnostic difference between them. A difference in color pattern was the most ap- propriate phenotypic character with which to distinguish between the two morphotypes. Complete mito- chondrial DNA sequencing, however, indicated a clear difference between the two morphotypes. Barcoding analysis revealed no significant difference (P〉0.05) in CO1 or ND2 divergence among intramorphotypic individuals, even between geographically separated populations, whereas the intermorphotypic CO1 and ND2 divergences were large enough (averaging 0.95% for CO1 and 1.37% for ND2) to clearly discriminate between the two morphotypes. The color pattern difference, geographical distribution, together with the mtDNA and barcode sequencing data, suggest that the two morphotypes should be of two subspecies or even two species. 展开更多
关键词 Plectropomus leopardus MORPHOTYPE omplete mitochondrial dna BARCODING
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NELL2,a novel osteoinductive factor,regulates osteoblast differentiation and bone homeostasis through fibronectin 1/integrin-mediated FAK/AKT signaling 被引量:1
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作者 Hairui Yuan Xinyu Wang +8 位作者 Shuanglin Du Mengyue Li Endong Zhu Jie Zhou Yuan Dong Shuang Wang Liying Shan Qian Liu Baoli Wang 《Bone Research》 2025年第4期895-909,共15页
Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was dimini... Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was diminished in the bone of aged and ovariectomized(OVX)mice,as well as in the serum of osteopenia and osteoporosis patients.In vitro loss-of-function and gain-offunction studies revealed that NELL2 facilitated osteoblast differentiation and impeded adipocyte differentiation from stromal progenitor cells.In vivo studies further demonstrated that the deletion of NELL2 in preosteoblasts resulted in decreased cancellous bone mass in mice.Mechanistically,NELL2 interacted with the FNI-type domain located at the C-terminus of Fibronectin 1(Fn1).Moreover,we found that NELL2 activated the focal adhesion kinase(FAK)/AKT signaling pathway through Fn1/integrinβ1(ITGB1),leading to the promotion of osteogenesis and the inhibition of adipogenesis.Notably,administration of NELL2-AAV was found to ameliorate bone loss in OVX mice.These findings underscore the significant role of NELL2 in osteoblast differentiation and bone homeostasis,suggesting its potential as a therapeutic target for managing osteoporosis. 展开更多
关键词 adipocyte differentiation osteoblast differentiation fak akt signaling FIBRONECTIN bone biology secreted protein stromal progenitor cells bone homeostasis
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基于环境DNA技术的花鳗鲡特异性检测及生物量评估
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作者 尹晓强 曾金凤 +6 位作者 张娜 刘宇明 张鑫 张思源 罗佳林 谢松光 宋一清 《水生态学杂志》 北大核心 2026年第2期195-203,共9页
基于eDNA定量技术建立花鳗鲡(Anguilla marmorata)种群丰度的qPCR检测方法,为野外种群资源评估提供一种快速、无损的工具,为花鳗鲡的种群保护和恢复提供科学基础。基于eDNA定量技术,根据花鳗鲡线粒体D-loop基因序列设计了特异性引物和Ta... 基于eDNA定量技术建立花鳗鲡(Anguilla marmorata)种群丰度的qPCR检测方法,为野外种群资源评估提供一种快速、无损的工具,为花鳗鲡的种群保护和恢复提供科学基础。基于eDNA定量技术,根据花鳗鲡线粒体D-loop基因序列设计了特异性引物和TaqMan探针,探究了个体密度与eDNA浓度关系以及eDNA降解规律。结果显示,创建的qPCR检测方法能特异地对花鳗鲡样本进行阳性扩增;构建的质粒标准品,最低检测浓度可达4.095×10^(-7) ng/μL,根据稀释后的标准品浓度对数和临界循环值(Ct)拟合了标准曲线,扩增效率达98.3%;eDNA浓度与花鳗鲡不同养殖密度成正相关性(R^(2)=0.998);花鳗鲡eDNA浓度随时间推移逐渐降解,能在水体中存在22 d左右。设计的花鳗鲡特异性引物和TaqMan探针以及qPCR检测方法特异性好、灵敏度高,可以对花鳗鲡生物量进行相对定量检测。 展开更多
关键词 花鳗鲡 环境dna 定性分析 生物量
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Phylogenetic relationship and genetic differentiation of Populus caspica and Populus alba using cpDNA and ITS noncoding sequences 被引量:1
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作者 Hamed Yousefzadeh Abasalt Hosseinzadeh Colagar +2 位作者 Effat Yousefi Maryam Badbar Gregor Kozlowski 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第2期451-461,共11页
Populus caspica Bornm.(section Leuce and subsection Albida), one of the most endangered endemic tree species in the Hyrcanian Forest in Iran, has numerous morphological characteristics that are closely similar to Popu... Populus caspica Bornm.(section Leuce and subsection Albida), one of the most endangered endemic tree species in the Hyrcanian Forest in Iran, has numerous morphological characteristics that are closely similar to Populus alba; to clarify their taxonomic relatedness and genetic differentiation and thus inform conservation strategies, we used the noncoding regions of chloroplast DNA(cpDNA; trnL-F and trnH-psbA) and the internal transcribed spacer(ITS). Leaf samples were collected from six populations across northern Iran. cpDNA and ITS fragments were amplified by universal primers using the PCR technique and directed sequencing. The results showed that P. caspica is genetically differentiated from P.alba, and two ITS variants were detected within some P.caspica individuals. Conflicts between topologies from ITS and plastid genomes were observed. High differentiation of P. caspica from the other Populus species shown in this study confirmed the diverging taxonomic status of this endangered species. We recommend in situ conservation measures(e.g., protected areas) for at least several populations of this species, especially in the plain regions of the Hyrcanian forest. 展开更多
关键词 ENDANGERED ENDEMIC species dna BARCODING Hyrcanian forest TAXONOMIC status
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EWS Knockdown and Taxifolin Treatment Induced Differentiation and Removed DNA Methylation from p53 Promoter to Promote Expression of Puma and Noxa for Apoptosis in Ewing’s Sarcoma 被引量:2
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作者 Mohammad Motarab Hossain Swapan Kumar Ray 《Journal of Cancer Therapy》 2014年第12期1092-1113,共22页
Ewing’s sarcoma is a pediatric tumor that mainly occurs in soft tissues and bones. Malignant characteristics of Ewing’s sarcoma are correlated with expression of EWS oncogene. We achieved knockdown of EWS expression... Ewing’s sarcoma is a pediatric tumor that mainly occurs in soft tissues and bones. Malignant characteristics of Ewing’s sarcoma are correlated with expression of EWS oncogene. We achieved knockdown of EWS expression using a plasmid vector encoding EWS short hairpin RNA (shRNA) to increase anti-tumor mechanisms of taxifolin (TFL), a new flavonoid, in human Ewing’s sarcoma cells in culture and animal models. Immunofluorescence microscopy and flow cytometric analysis showed high expression of EWS in human Ewing’s sarcoma SK-N-MC and RD-ES cell lines. EWS shRNA plus TFL inhibited 80% cell viability and caused the highest decreases in EWS expression at mRNA and protein levels in both cell lines. Knockdown of EWS expression induced morphological features of differentiation. EWS shRNA plus TFL caused more alterations in molecular markers of differentiation than either agent alone. EWS shRNA plus TFL caused the highest decreases in cell migration with inhibition of survival, angiogenic and invasive factors. Knockdown of EWS expression was associated with removal of DNA methylation from p53 promoter, promoting expression of p53, Puma, and Noxa. EWS shRNA plus TFL induced the highest amounts of apoptosis with activation of extrinsic and intrinsic pathways in both cell lines in culture. EWS shRNA plus TFL also inhibited growth of Ewing’s sarcoma tumors in animal models due to inhibition of differentiation inhibitors and angiogenic and invasive factors and also induction of activation of caspase-3 for apoptosis. Collectively, knockdown of EWS expression increased various anti-tumor mechanisms of TFL in human Ewing’s sarcoma in cell culture and animal models. 展开更多
关键词 APOPTOSIS differentiation Ewing’s Sarcoma EWS shRNA P53 PROMOTER TAXIFOLIN
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Genetic Differentiation Analyses Based on mtDNA COⅡ Gene Sequences Among Different Geographic Populations of Aphis glycines(Hemiptera: Aphididae) in Northeast China 被引量:1
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作者 Li Ran Han Lan-lan +4 位作者 Ye Le-fu Zhang Hong-yu Sun Wen-peng Tong Xin Zhao Kui-jun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第3期23-31,共9页
Aphis glycines (Hemiptera: Aphididae) is considered as a cosmopolitan pest of cultivated soybean, major difficulties in its control measures may be due to its higher genetic diversity; however, the knowledge about ... Aphis glycines (Hemiptera: Aphididae) is considered as a cosmopolitan pest of cultivated soybean, major difficulties in its control measures may be due to its higher genetic diversity; however, the knowledge about population genetic diversity of this species is limited. This study aimed to represent the genetic differentiation among different geographic populations of soybean aphid in Northeast China. In order to investigate and assess the genetic diversity, genetic differentiation, molecular variance, population structure, ecological importance and evolutionary history of A. glycines, we sequenced a fragment of one protein-coding gene, the cytochrome c oxidase I/of mitochondrial DNA gene. The results showed that four haplotypes were defined among CO 11 gene of 180 sequences of soybean aphid in Northeast China including H1 shared by all the populations. Lower haplotype diversity (Hd=0.3590± 0.0420) and nucleotide diversity (Pi=0.0012±0.0002) were observed and high gene flow was detected in every two populations, while most of the variation (80.81%) arose from variability within A. glycines from individuals. Low genetic differentiation and high gene flow (Nm=2.106) indicated a high migration rate between the populations, which might reveal that gene flow in different geographic populations did not affect by geographical distance. The phylogenetic tree and the haplotype network ofA. glycines were obtained based on sequences of CO Ⅱ gene, there were no significant genealogical branches or clusters recognized in NJ tree, and no clear distribution, delineation of haplotypes were demonstrated in the haplotype network according to geographical location. This study rejected the vicariance hypothesis: geographic isolation could be a barrier and it restricted A. glycines gene flow among 10 populations. 展开更多
关键词 Aphis glycines mtdna CO geographic population gene flow genetic differentiation
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地肤子及其伪品的DNA条形码技术鉴定研究
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作者 孙一帆 牛倩 +6 位作者 程翔 任秀芹 王默含 胡建建 栗进才 孟祥松 王孟虎 《陕西中医药大学学报》 2026年第1期120-125,共6页
目的 采用DNA条形码ITS2及其二级结构对地肤子及混伪品进行鉴定。方法 收集地肤子药材及其混伪品,基于ITS2通用引物进行PCR扩增及双向测序,所得序列用CodonCode Aligner10.0.2软件校对拼接,利用MEGA 11.0对序列进行比对分析,计算种内、... 目的 采用DNA条形码ITS2及其二级结构对地肤子及混伪品进行鉴定。方法 收集地肤子药材及其混伪品,基于ITS2通用引物进行PCR扩增及双向测序,所得序列用CodonCode Aligner10.0.2软件校对拼接,利用MEGA 11.0对序列进行比对分析,计算种内、种间遗传距离,利用邻接法构建系统发育树,并应用ITS2数据库网站预测其ITS2二级结构。结果 地肤子种内遗传距离明显小于各物种种间遗传距离,基于ITS2建立的邻接法系统发育树能准确将地肤子与其混伪品进行鉴别;基于各物种ITS2序列构建的二级结构能够准确将地肤子及其混伪品进行鉴别。结论 基于DNA条形码ITS2序列及其二级结构可以准确地鉴别地肤子及其混伪品。 展开更多
关键词 地肤子 ITS2 二级结构 dna条形码 鉴定
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Genetic diversity and differentiation of masu salmon(Oncorhynchus masou masou)between and within cultured populations inferred from microsatellite DNA analysis 被引量:2
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作者 Zhiying JI Yuyong ZHANG +1 位作者 Shuqiang CHEN Lianyu SHI 《Zoological Research》 CAS CSCD 北大核心 2012年第4期I0005-I0011,共7页
Masu salmon,Oncorhynchus masou masou,is one of the most valuable fishery species that has been introduced to China,though to date no studies on the genetic diversity and genetic relationship among hatchery populations... Masu salmon,Oncorhynchus masou masou,is one of the most valuable fishery species that has been introduced to China,though to date no studies on the genetic diversity and genetic relationship among hatchery populations has been performed with molecular markers.We undertook such a study and sampled 120 individuals from three hatchery stocks and analyzed 20 microsatellite loci.All loci were polymorphic and a total of 91 alleles were detected.A relatively low level of genetic diversity was revealed with effective number of allele of 3.1094,3.3299 and 3.1894 and expected heterozygosity of 0.6600,0.6648 and 0.6638 in the three stocks,respectively.Deviations from Hardy-Weinberg equilibrium were found due to heterozygote deficit.Accordingly,evidence of genetic bottlenecks were found in the three stocks.An individual assignment test demonstrated that 85%of individuals were correctly assigned into their original stocks.Pairwise Fst revealed that significant differentiation occurred between these three stocks.The results of the study indicated that disequilibrium of genetic structure and differentiation has occurred in all three stocks.This information collectively provides a basis for measures to avoid of loss of genetic diversity and introgression in Chinese aquaculture. 展开更多
关键词 Oncorhynchus masou masou MICROSATELLITE Genetic diversity Genetic differentiation
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Differentiation of Avian Pathogenic <i>Escherichia coli</i>Strains from Broiler Chickens by Multiplex Polymerase Chain Reaction (PCR) and Random Amplified Polymorphic (RAPD) DNA 被引量:2
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作者 Dirgam Ahmad Roussan Hana Zakaria +1 位作者 Ghassan Khawaldeh Ibrahim Shaheen 《Open Journal of Veterinary Medicine》 2014年第10期211-219,共9页
We examined 50 Escherichia coli (E. coli) strains isolated from broiler chickens between January 2013 to March 2014 in order to evaluate the epidemiological prevalence of avian pathogenic E. coli (APEC) in Jordan by m... We examined 50 Escherichia coli (E. coli) strains isolated from broiler chickens between January 2013 to March 2014 in order to evaluate the epidemiological prevalence of avian pathogenic E. coli (APEC) in Jordan by multiplex PCR and random amplification of polymorphic DNA (RAPD) tests. The multiplex polymerase chain reaction (PCR) which was used as tentative criteria of APEC targets 8 virulence associated genes;enteroaggregative toxin (astA), Type 1 fimbria adhesion (fimH), iron-repressible protein (irp2), P fimbriae (papC), aerobactin (iucD), temperature-sensitive hemagglutinin (tsh), vacuolating autotransporter toxin (vat), and colicin V plasmid operon (cva/cvi) genes. The number of detected genes could be used as a reliable index of their virulence. E. coli strains already typed as an APEC always harbor 5 to 8 genes, but non-APEC strains harbor less than 4 genes. Assuming the criteria of an APEC is possession of 5 or more virulence associated genes;we found that all 50 E. coli strains were classified as APEC strains. The RAPD analysis showed that the E. coli strains could be grouped into 35 of RAPD types by using these two different RAPD primer sets, RAPD analysis primer 4 5'AAGAGCCCGT5', and RAPD analysis primer 6 5'CCCGTCAGCA3'. The current study confirmed the endemic nature of APEC in broiler flocks in Jordan. It is essential that the biosecurity on poultry farms should be improved to prevent the introduction and dissemination of APEC and other agents. Furthermore, farmers need to be educated about the signs, lesions, and the importance of this agent. 展开更多
关键词 AVIAN PATHOGENIC Escherichia coli Broiler Multiplex PCR RANDOM Amplification of POLYMORPHIC dna
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Insight into leaching rare earth from ion-adsorption type rare earth ores with citric acid:Performance,kinetic analysis and differentiation leaching 被引量:1
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作者 Mengfei Zhao Zedong Teng +4 位作者 Xingyu Ma Xiaoliang Jiang Hualin Zhang Youming Yang Tinggang Li 《Journal of Rare Earths》 2025年第3期591-602,I0007,共13页
The rare earth elements(REEs)extraction by chemical leaching from ion-adsorption type rare earth ores(IAREO)has led to serious ecological and environmental risks.Conversely,demand for bioleaching is on the rise with t... The rare earth elements(REEs)extraction by chemical leaching from ion-adsorption type rare earth ores(IAREO)has led to serious ecological and environmental risks.Conversely,demand for bioleaching is on the rise with the advantage of being environmental-friendly.As one of the organic acids produced by biological metabolism,citric acid was used to leach REEs and explore the performance and process.The results demonstrate that citric acid exhibits higher leaching efficiency(96.00%)for REEs at a relatively low concentration of 0.01 mol/L compared with(NH_(4))_(2)SO_(4)(84.29%,0.1 mol/L)and MgSO_(4)(83.99%,0.1 mol/L).Citric acid shows a preference for leaching heavy rare earth elements,with 99%leaching efficiency in IAREO,which shows higher capacity than(NH_(4))_(2)SO_(4)and MgSO_(4)(as inorganic leaching agents).Kinetic analysis indicates that the leaching process of REEs with citric acid is controlled by both the internal diffusion kinetics and chemical reaction kinetics,which is different from inorganic leaching agents.Visual Minteq calculations confirm that RE-Citrate is the main constituent of the extract solution in the leaching process of the IAREO,thereby enhancing the leaching efficiency of REEs from the IAREO.It suggests that citric acid may be used as a promising organic leaching agent for the environmentalfriendly extraction of REEs from IAREO. 展开更多
关键词 Ion-adsorption type rare earth ores Rare earths Citric acid COMPLEXATION Organic acid differential leaching
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脓毒症患者循环游离DNA甲基化特征及其临床应用前景
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作者 晏梓豪(综述) 龚艺(审校) 《国际检验医学杂志》 2026年第1期91-96,共6页
脓毒症是感染诱发的宿主失调性炎症反应所致的器官功能障碍,具有高发病率和高病死率。循环游离DNA(cfDNA)作为一种来源于细胞凋亡、坏死及免疫过程的分子标志,近年来受到广泛关注。cfDNA不仅在浓度水平上反映机体组织损伤,其片段组学和... 脓毒症是感染诱发的宿主失调性炎症反应所致的器官功能障碍,具有高发病率和高病死率。循环游离DNA(cfDNA)作为一种来源于细胞凋亡、坏死及免疫过程的分子标志,近年来受到广泛关注。cfDNA不仅在浓度水平上反映机体组织损伤,其片段组学和甲基化特征更携带组织来源及免疫状态信息,为脓毒症的诊断、分型及预后评估提供了新的思路。该文总结了cfDNA甲基化的检测方法、脓毒症患者cfDNA甲基化特征的研究进展,分析其在器官损伤监测、免疫失衡评估及疾病预后中的应用潜力,并提出当前研究尚待解决的问题。 展开更多
关键词 脓毒症 循环游离dna dna甲基化 免疫失衡 预后评估
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Photobiomodulation:a novel approach to promote trans-differentiation of adipose-derived stem cells into neuronal-like cells
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作者 Daniella Da Silva Madeleen Jansen van Rensburg +1 位作者 Anine Crous Heidi Abrahamse 《Neural Regeneration Research》 SCIE CAS 2025年第2期598-608,共11页
Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infr... Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infrared light promotes adipose stem cell proliferation and affects adipose stem cell migration,which is necessary for the cells homing to the site of injury.In this in vitro study,we explored the potential of adipose-derived stem cells to differentiate into neurons for future translational regenerative treatments in neurodegenerative disorders and brain injuries.We investigated the effects of various biological and chemical inducers on trans-differentiation and evaluated the impact of photobiomodulation using 825 nm near-infrared and 525 nm green laser light at 5 J/cm2.As adipose-derived stem cells can be used in autologous grafting and photobiomodulation has been shown to have biostimulatory effects.Our findings reveal that adipose-derived stem cells can indeed trans-differentiate into neuronal cells when exposed to inducers,with pre-induced cells exhibiting higher rates of proliferation and trans-differentiation compared with the control group.Interestingly,green laser light stimulation led to notable morphological changes indicative of enhanced trans-differentiation,while near-infrared photobiomodulation notably increased the expression of neuronal markers.Through biochemical analysis and enzyme-linked immunosorbent assays,we observed marked improvements in viability,proliferation,membrane permeability,and mitochondrial membrane potential,as well as increased protein levels of neuron-specific enolase and ciliary neurotrophic factor.Overall,our results demonstrate the efficacy of photobiomodulation in enhancing the trans-differentiation ability of adipose-derived stem cells,offering promising prospects for their use in regenerative medicine for neurodegenerative disorders and brain injuries. 展开更多
关键词 differentiation inducers green photobiomodulation immortalized adipose-derived stem cell near-infrared photobiomodulation neurodegenerative disease NEUROGENESIS PHOTOBIOMODULATION TRANS-differentiation
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