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The 2-adic complexity of sum sequences of Legendre sequences
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作者 JING Xiaoyan XU Zhefeng FENG Keqin 《纯粹数学与应用数学》 2025年第2期191-199,共9页
Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequenc... Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequence of any k many Legendre sequences and show that the 2-adic complexity of the sum sequences of any k many Legendre sequences reaches the maximum by proving the case of k=2 and 3,which implies that the sum sequences can resist the attack of rational approximation algorithm. 展开更多
关键词 2-adic complexity binary sequences Legendre symbol Legendre sequences
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Predicting Diabetic Retinopathy Using a Machine Learning Approach Informed by Whole-Exome Sequencing Studies
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作者 Chongyang She Wenying Fan +2 位作者 Yunyun Li Yong Tao Zufei Li 《Biomedical and Environmental Sciences》 2025年第1期67-78,共12页
Objective To establish and validate a novel diabetic retinopathy(DR)risk-prediction model using a whole-exome sequencing(WES)-based machine learning(ML)method.Methods WES was performed to identify potential single nuc... Objective To establish and validate a novel diabetic retinopathy(DR)risk-prediction model using a whole-exome sequencing(WES)-based machine learning(ML)method.Methods WES was performed to identify potential single nucleotide polymorphism(SNP)or mutation sites in a DR pedigree comprising 10 members.A prediction model was established and validated in a cohort of 420 type 2 diabetic patients based on both genetic and demographic features.The contribution of each feature was assessed using Shapley Additive explanation analysis.The efficacies of the models with and without SNP were compared.Results WES revealed that seven SNPs/mutations(rs116911833 in TRIM7,1997T>C in LRBA,1643T>C in PRMT10,rs117858678 in C9orf152,rs201922794 in CLDN25,rs146694895 in SH3GLB2,and rs201407189 in FANCC)were associated with DR.Notably,the model including rs146694895 and rs201407189 achieved better performance in predicting DR(accuracy:80.2%;sensitivity:83.3%;specificity:76.7%;area under the receiver operating characteristic curve[AUC]:80.0%)than the model without these SNPs(accuracy:79.4%;sensitivity:80.3%;specificity:78.3%;AUC:79.3%).Conclusion Novel SNP sites associated with DR were identified in the DR pedigree.Inclusion of rs146694895 and rs201407189 significantly enhanced the performance of the ML-based DR prediction model. 展开更多
关键词 Machine learning Diabetic retinopathy Whole exome sequencing Type 2 diabetes mellitus
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To Analyze the Sensitivity of RT-PCR Assays Employing S Gene Target Failure with Whole Genome Sequencing Data during Third Wave by SARS-CoV-2 Omicron Variant
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作者 Pooja Patel Yogita Mistry +1 位作者 Monika Patel Summaiya Mullan 《Advances in Microbiology》 CAS 2024年第5期247-255,共9页
Introduction: Omicron is a highly divergent variant of concern (VOCs) of a severe acute respiratory syndrome SARS-CoV-2. It carries a high number of mutations in its spike protein hence;it is more transmissible in the... Introduction: Omicron is a highly divergent variant of concern (VOCs) of a severe acute respiratory syndrome SARS-CoV-2. It carries a high number of mutations in its spike protein hence;it is more transmissible in the community by immune evasion mechanisms. Due to mutation within S gene, most Omicron variants have reported S gene target failure (SGTF) with some commercially available PCR kits. Such diagnostic features can be used as markers to screen Omicron. However, Whole Genome Sequencing (WGS) is the only gold standard approach to confirm novel microorganisms at genetically level as similar mutations can also be found in other variants that are circulating at low frequencies worldwide. This Retrospective study is aimed to assess RT-PCR sensitivity in the detection of S gene target failure in comparison with whole genome sequencing to detect variants of Omicron. Methods: We have analysed retrospective data of SARS-CoV-2 positive RT-PCR samples for S gene target failure (SGTF) with TaqPath COVID-19 RT-PCR Combo Kit (ThermoFisher) and combined with sequencing technologies to study the emerged pattern of SARS-CoV-2 variants during third wave at the tertiary care centre, Surat. Results: From the first day of December 2021 till the end of February 2022, a total of 321,803 diagnostic RT-PCR tests for SARS-CoV-2 were performed, of which 20,566 positive cases were reported at our tertiary care centre with an average cumulative positivity of 6.39% over a period of three months. In the month of December 21 samples characterized by the SGTF (70/129) were suggestive of being infected by the Omicron variant and identified as Omicron (B.1.1.529 lineage) when sequence. In the month of January, we analysed a subset of samples (n = 618) with SGTF (24%) and without SGTF (76%) with Ct values Conclusions: During the COVID-19 pandemic, it took almost more than 15 days to diagnose infection and identify pathogen by sequencing technology. In contrast to that molecular assay provided quick identification with the help of SGTF phenomenon within 5 hours of duration. This strategy helps scientists and health policymakers for the quick isolation and identification of clusters. That ultimately results in a decreased transmission of pathogen among the community. 展开更多
关键词 SARS-CoV-2 S Gene Target Failure Whole Genome sequencing Omicron
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Accurate Diagnosis of SARS-CoV-2 JN.1 by Sanger Sequencing of Receptor-Binding Domain Is Needed for Clinical Evaluation of Its Immune Evasion
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作者 Sin Hang Lee 《Journal of Biosciences and Medicines》 2024年第4期69-78,共10页
Background: Omicron JN.1 has become the dominant SARS-CoV-2 variant in recent months. JN.1 has the highest number of amino acid mutations in its receptor binding domain (RBD) and has acquired a hallmark L455S mutation... Background: Omicron JN.1 has become the dominant SARS-CoV-2 variant in recent months. JN.1 has the highest number of amino acid mutations in its receptor binding domain (RBD) and has acquired a hallmark L455S mutation. The immune evasion capability of JN.1 is a subject of scientific investigation. The US CDC used SGTF of TaqPath COVID-19 Combo Kit RT-qPCR as proxy indicator of JN.1 infections for evaluation of the effectiveness of updated monovalent XBB.1.5 COVID-19 vaccines against JN.1 and recommended that all persons aged ≥ 6 months should receive an updated COVID-19 vaccine dose. Objective: Recommend Sanger sequencing instead of proxy indicator to diagnose JN.1 infections to generate the data based on which guidelines are made to direct vaccination policies. Methods: The RNA in nasopharyngeal swab specimens from patients with clinical respiratory infection was subjected to nested RT-PCR, targeting a 398-base segment of the N-gene and a 445-base segment of the RBD of SARS-CoV-2 for amplification. The nested PCR amplicons were sequenced. The DNA sequences were analyzed for amino acid mutations. Results: The N-gene sequence showed R203K, G204R and Q229K, the 3 mutations associated with Omicron BA.2.86 (+JN.1). The RBD sequence showed 24 of the 26 known amino acid mutations, including the hallmark L455S mutation for JN.1 and the V483del for BA.2.86 lineage. Conclusions: Sanger sequencing of a 445-base segment of the SARS-CoV-2 RBD is useful for accurate determination of emerging variants. The CDC may consider using Sanger sequencing of the RBD to diagnose JN.1 infections for statistical analysis in making vaccination policies. 展开更多
关键词 Omicron JN.1 SARS-CoV-2 Sanger sequencing RBD L455S Mutation Immune Evasion Vaccination Policies CDC
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Complete Genome Sequencing and Genetic Variation Analysis of Two H9N2 Subtype Avian Influenza Virus Strains 被引量:2
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作者 沈佳 章振华 +3 位作者 姜北宇 李林 景小冬 张建伟 《Agricultural Science & Technology》 CAS 2011年第2期291-294,共4页
[Objective] The study aimed to investigate the genetic variation characters of entire sequences between two H9N2 subtype avian influenza virus strains and other reference strains.[Method] The entire sequences of 8 gen... [Objective] The study aimed to investigate the genetic variation characters of entire sequences between two H9N2 subtype avian influenza virus strains and other reference strains.[Method] The entire sequences of 8 genes were obtained by using RT-PCR,and these sequences were analyzed with that of six H9N2 subtype avian influenza isolates in homology comparison and genetic evolution relation.[Result] The results showed that the nucleotide sequence of entire gene of the strain shared 91.1%-95.4% homology with other seven reference strains,and PG08 shared the highest homology 91.3% with C/BJ/1/94;ZD06 shared the highest homology 92.3% with D/HK/Y280/97.HA cleavage sites of two H9N2 subtype avian influenza virus isolated strains were PARSSR/GLF,typical of mildly pathogenic avian influenza virus.[Conclusion] Phylogenetic tree for entire gene of eight strains showed that the genetic relationship was the closest between ZD06 and C/Pak/2/99 strains,which belonged to the Eurasian lineage;PG08 shared the highest homology 91.3% with ZD06,it may be the product of gene rearrangements of other sub-lines. 展开更多
关键词 Avian influenza virus H9N2 subtype Complete genome sequence analysis
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内皮细胞特异性骨形态发生蛋白2对血管新生的影响:生物信息学分析和实验验证
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作者 燕茹 王凯茹 +2 位作者 张飞燕 贾绍斌 丛广志 《中国组织工程研究》 CAS 北大核心 2025年第1期103-110,共8页
背景:血管新生是心血管疾病的主要干预靶点,骨形态发生蛋白2具有调控血管新生作用,但内皮细胞特异性骨形态发生蛋白2对血管新生的调控作用不清楚。目的:探讨内皮细胞特异性骨形态发生蛋白2对血管新生的影响。方法:(1)生物信息学分析:通... 背景:血管新生是心血管疾病的主要干预靶点,骨形态发生蛋白2具有调控血管新生作用,但内皮细胞特异性骨形态发生蛋白2对血管新生的调控作用不清楚。目的:探讨内皮细胞特异性骨形态发生蛋白2对血管新生的影响。方法:(1)生物信息学分析:通过Panglao DB公共基因表达数据库单细胞转录组荟萃分析观察骨形态发生蛋白2细胞群表达丰度和定位。血管新生小鼠和内皮(心内膜)过表达骨形态发生蛋白2小鼠转录组测序数据集探索内皮细胞骨形态发生蛋白2对血管新生信号通路的调控作用。(2)体内实验验证:建立小鼠后肢缺血模型,对比模型小鼠患侧与健侧缺血后肢7,14和21 d血流灌注情况,免疫荧光和免疫组织化学染色评估小鼠骨形态发生蛋白2和CD31的表达定位情况。(3)体外实验验证:体外培养人脐静脉内皮细胞,分为对照组、缺氧组和骨形态发生蛋白2抑制剂(Noggin蛋白)干预组,培养24 h,观察各组内皮细胞血管新生情况。结果与结论:(1)内皮细胞是表达骨形态发生蛋白2的重要细胞亚群,在血管新生内皮细胞和骨形态发生蛋白2过表达内皮细胞转录组再分析均发现骨形态发生蛋白2表达明显升高,血管新生通路明显激活。(2)缺血7 d小鼠新生血管周围骨形态发生蛋白2阳性血管明显增加(P<0.05),缺血2周骨形态发生蛋白2阳性血管明显减少(P<0.001)。(3)体外培养人脐静脉内皮细胞,缺氧干预后,内皮细胞迁移能力和血管出芽明显增加,血管新生因子血管内皮生长因子和血小板衍生生长因子的表达明显升高,Noggin明显减少了缺氧诱导的内皮细胞血管新生(P<0.001),并下调血管内皮生长因子和血小板衍生生长因子的表达(P<0.01)。(4)结果证实,内皮细胞特异性骨形态发生蛋白2具有调控血管新生作用,靶向性内皮细胞骨形态发生蛋白2可望改善血管新生。 展开更多
关键词 内皮细胞 骨形态发生蛋白2 血管新生 单细胞RNA测序 批量RNA测序 信号通路 后肢缺血模型 成管实验
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应用16S rRNA基因测序技术比较不同品系2型糖尿病大鼠肠道菌群的异同
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作者 刘军 齐晏永 +2 位作者 郭超 高伟 牛苗苗 《实验动物科学》 2025年第2期44-51,共8页
目的比较SD和GK两个品系大鼠建立的2型糖尿病(T2DM)模型肠道菌群组成和多样性的异同,为探索两模型在T2DM相关肠道菌群研究中的进一步应用提供背景数据。方法采用8周龄SPF级雄性SD和GK大鼠各20只,SD组大鼠高脂饲料饲喂6周后,单次腹腔注射... 目的比较SD和GK两个品系大鼠建立的2型糖尿病(T2DM)模型肠道菌群组成和多样性的异同,为探索两模型在T2DM相关肠道菌群研究中的进一步应用提供背景数据。方法采用8周龄SPF级雄性SD和GK大鼠各20只,SD组大鼠高脂饲料饲喂6周后,单次腹腔注射30 mg/kg的链脲佐菌素(STZ),GK组大鼠高脂饲料诱导4周后出现糖尿病症状,两组大鼠空腹血糖≥11.1 mmol/L为T2DM建模成功,分别收集每组10只大鼠建模成功6周后的洁净粪便各10份,进行16S rRNA基因V3-V4区测序,分析粪便中肠道菌群的Alpha多样性、Beta多样性、优势菌属及肠道菌群相关的功能通路。结果SD组与GK组大鼠肠道菌群的Alpha多样性和丰富度没有显著差异,两组大鼠肠道菌群Beta多样性指数显著不同(均P<0.05)。GK组T2DM大鼠肠道的优势菌属为乳酸杆菌属、未分类梭菌属_UCG_014、未分类鼠杆菌科、阿克曼菌和瘤胃球菌属;SD组T2DM大鼠的优势菌属为异杆菌属、乳酸杆菌属、毛螺菌科_NK4A136组、链球菌属、瘤胃球菌属、UCG-005和联合乳酸杆菌属;两组的优势菌属在组成和比例上差异很大。两组T2DM大鼠肠道菌群的功能通路主要集中在氨基酸代谢、糖代谢、核苷酸代谢和脂代谢为主的代谢途径中。结论两组T2DM大鼠肠道菌群Alpha多样性无差异,但肠道菌群的组成及比例差异较大,优势菌群在不同T2DM模型中的组成比例发生了改变。 展开更多
关键词 大鼠 2型糖尿病 肠道菌群 16S rRNA基因测序
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2型糖尿病患者不同中医证型与肠道菌群的关系研究 被引量:1
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作者 刘泓 梁晓辉 +3 位作者 温小凤 张晓白 卜献春 吴刚强 《四川大学学报(医学版)》 北大核心 2025年第2期389-399,共11页
目的观察中医不同证型下2型糖尿病患者肠道菌群的特征,进一步探讨影响证型分化的关键微生物群及功能差异。方法选取2023年在湖南省中西医结合医院老年病科就诊的45例患者,包括15例2型糖尿病气阴两虚兼瘀证患者(A组)、15例2型糖尿病气阴... 目的观察中医不同证型下2型糖尿病患者肠道菌群的特征,进一步探讨影响证型分化的关键微生物群及功能差异。方法选取2023年在湖南省中西医结合医院老年病科就诊的45例患者,包括15例2型糖尿病气阴两虚兼瘀证患者(A组)、15例2型糖尿病气阴两虚证患者(B组)和15例同期未患糖尿病者(C组)。采集患者粪便标本,应用16S r RNA进行测序和分析。结果(1)三组患者得到了1564个操作分类单元(operational taxonomic units,OTUs),其中A、B、C组所特有的OTUs数分别为224、127和351个。(2)α和β多样性表明三组肠道微生物群之间存在差异,如:α多样性分析中,Sobs指数在三组间存在组间差异(P<0.01),A组(264.00±88.84)大于B组(145.90±87)(P<0.01),B组则小于C组(229.7±112.4)(P<0.05);β多样性分析中,主坐标分析(principal coordinate analysis,PCo A)提示三组组间分离明显(R=0.1610,P<0.01),Anosim/Adonis分析中R值在0.144~0.196间,R2值在0.067~0.083间,均提示组间对比存在差异(P<0.01)。(3)在门一级,各组均以厚壁菌门、放线菌门、拟杆菌门为主,其中拟杆菌门在三组间存在差异(P<0.05),且在A组中的占比高于B组(P<0.01)。(4)通过菌群组成差异分析结果、LEf Se(Linear discriminant analysis Effect Size)结合Random Forest分析,认为在属一级,A组和B组之间的菌群标志物是副拟杆菌属、拟杆菌属、某一未命名乳酸菌属、罗氏菌属、黄曲霉属;B组和C组之间的菌群标志物是Erysipelotrichaceae_UCG-003属、瘤胃球菌属;A组和C组间的有副拟杆菌属、厌氧菌属、颤杆菌克属。该结果通过受试者操作特征(receiver operating characteristic,ROC)曲线分析检验,认为A组和B组[曲线下面积(area under the curve,AUC)=0.91,95%置信区间(confidence interval,CI):0.80~1.00]、B组和C组(AUC=0.84,95%CI:0.69~0.99)、A组和C组(AUC=0.87,95%CI:0.75~0.99)间的菌群标志物具有较好的诊断效能。(5)研究通过京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)分析确定了116条存在组间差异的主要通路,如ABC transporters通路富集程度在A组(2.58±0.36)中低于B组(2.90±0.48)和C组(3.11±0.66)(P<0.05),这些通路与新陈代谢和环境信息处理等有关。结论2型糖尿病特殊证型患者的肠道菌群特征和功能差异可为中医辨证分型和治疗机制提供参考。 展开更多
关键词 2型糖尿病 肠道菌群 16S rRNA测序
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超临界CO_(2)对页岩断裂裂缝形态的影响 被引量:1
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作者 吴华 王小琼 +4 位作者 葛洪魁 汪海阁 何吉祥 张彦龙 王建勇 《石油机械》 北大核心 2025年第6期130-140,共11页
超临界二氧化碳(SC-CO_(2))前置压裂过程中,前置注入的CO_(2)容易进入页岩多孔介质中,并与地层水或者水基压裂液结合形成弱酸性流体,激发页岩微裂缝萌生扩展。为了明确CO_(2)对页岩微裂缝萌生扩展的影响,开展了加压浸泡-单轴压缩联合试... 超临界二氧化碳(SC-CO_(2))前置压裂过程中,前置注入的CO_(2)容易进入页岩多孔介质中,并与地层水或者水基压裂液结合形成弱酸性流体,激发页岩微裂缝萌生扩展。为了明确CO_(2)对页岩微裂缝萌生扩展的影响,开展了加压浸泡-单轴压缩联合试验,研究了流体类型、浸泡时间、浸泡顺序对页岩微裂缝萌生扩展的影响。研究结果表明:CO_(2)前置注入能促进层理缝开启,CO_(2)作用时间越长,层理缝开启数量越多。压力降低时,SC-CO_(2)开启的层理裂缝容易闭合,但“SC-CO_(2)→水”复合作用时,水易进入CO_(2)开启的层理缝中形成有效支撑,与CO_(2)反应生成碳酸溶蚀碳酸盐岩矿物,弱化页岩的力学强度,促进微裂纹扩展,形成复杂且稳定的缝网。而“水→SC-CO_(2)”复合作用时,水在压差和毛细管力的作用下渗吸进入页岩微小孔隙中,在孔隙壁面形成大量水膜,严重阻碍了CO_(2)向页岩内部扩散,使其难以有效开启层理缝。垂直层理样品裂缝扩展主要受加载应力控制,流体的影响较弱,破裂后普遍形成一个倾斜贯穿层理的破裂面。研究结果可为优化页岩CO_(2)前置压裂工艺参数设计提供理论依据,对于提升页岩油的开发效率及促进CO_(2)地质封存具有重要意义。 展开更多
关键词 前置压裂 超临界CO_(2) 页岩 CO_(2)浸泡方式 浸泡顺序 单轴压缩 裂缝形态
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Effects of impregnation sequence on the NH_(3)-SCR activity and hydrothermal stability of a Ce-Nb/SnO_(2) catalyst 被引量:1
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作者 Ying Zhu Wenpo Shan +3 位作者 Zhihua Lian Jingjing Liu Yan Zhang Hong He 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第4期450-457,共8页
Hydrothermal stability is crucial for the practical application of deNO_(x)catalyst on diesel vehicles,for the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).SnO_(2)-based materials possess superior hy... Hydrothermal stability is crucial for the practical application of deNO_(x)catalyst on diesel vehicles,for the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).SnO_(2)-based materials possess superior hydrothermal stability,which is attractive for the development of NH_(3)-SCR catalyst.In this work,a series of Ce-Nb/SnO_(2)catalysts,with Ce and Nb loading on SnO_(2)support,were prepared by impregnation method.It was found that,the NH_(3)-SCR activities and hydrothermal stabilities of the Ce-Nb/SnO_(2)catalysts significantly varied with the impregnation sequences,and the Ce-Nb(f)/SnO_(2) catalyst that firstly impregnated Nb and then impregnated Ce exhibited the best performance.The characterization results revealed that CeNb(f)/SnO_(2)possessed appropriate acidity and redox capability.Furthermore,the strong synergistic effect between Nb and Sn species stabilized the structure and maintained the dispersion of acid sites.This study may provide a new understanding for the effect of impregnation sequence on activity and hydrothermal stability and a new environmental-friendly NH_(3)-SCR catalyst with potential applications for NO_(x)removal from diesel and hydrogenfueled engines. 展开更多
关键词 NO_(x)emission control NH_(3)-SCR Hydrothermal stability Ce-Nb/SnO_(2)catalyst Impregnation sequence
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基于单细胞测序技术揭示2'-5'-寡腺苷酸合成酶2在胰腺导管腺癌肿瘤相关巨噬细胞中的作用 被引量:1
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作者 汪子欣 杨玉洁 +1 位作者 王越 赵云鹏 《海军军医大学学报》 北大核心 2025年第5期567-576,共10页
目的 基于早期和晚期胰腺导管腺癌(PDAC)患者肿瘤组织巨噬细胞相关的差异基因,探索PDAC肿瘤免疫微环境的特征,为PDAC提供早诊早治新靶点。方法 收集3例早期与4例晚期PDAC患者肿瘤组织样本,利用单细胞测序技术分析组织转录组数据,结合癌... 目的 基于早期和晚期胰腺导管腺癌(PDAC)患者肿瘤组织巨噬细胞相关的差异基因,探索PDAC肿瘤免疫微环境的特征,为PDAC提供早诊早治新靶点。方法 收集3例早期与4例晚期PDAC患者肿瘤组织样本,利用单细胞测序技术分析组织转录组数据,结合癌症基因组图谱(TCGA)数据库,获取与预后有关的早期与晚期PDAC差异表达的巨噬细胞相关基因,采用最小绝对收缩和选择算子(LASSO)-Cox回归方法构建预后风险评分模型。利用基因表达谱交互分析2(GEPIA2)在线生存分析工具筛选出与PDAC预后相关的风险基因,使用通过估计RNA转录本相对子集进行细胞类型鉴定(CIBERSORT)方法对其免疫浸润情况进行分析,通过t-分布随机近邻嵌入(tSNE)聚类降维和Monocle包对其在不同时期不同亚群巨噬细胞中的表达情况进行解析,并进一步借助STRING数据库及人类蛋白质图谱(HPA)数据库对其蛋白质-蛋白质相互作用和免疫组织化学染色图片进行分析。结果 共发现48个早期与晚期PDAC差异表达的巨噬细胞相关基因与预后有关。筛选出11个差异表达的巨噬细胞基因作为PDAC预后基因,并利用这11个基因构建PDAC预后风险评分模型。筛选出2个不良预后基因,其中2'-5'-寡腺苷酸合成酶2(OAS2)基因主要在分泌型磷蛋白1(SPP1)阳性巨噬细胞中表达,人类异常纺锤体样小头畸形相关蛋白(ASPM)基因主要在增殖标志物Ki-67(MKI67)阳性巨噬细胞中表达,并且OAS2在不同时期PDAC巨噬细胞中的表达具有明显差异。免疫浸润研究表明OAS2和ASPM在调节性T细胞、M2型巨噬细胞中高表达(均P<0.05)。蛋白质-蛋白质相互作用网络显示了OAS2和ASPM间的表达关系以及更多其他共表达的蛋白。免疫组织化学分析表明OAS2在肿瘤组织中的表达水平高于正常组织。结论 OAS2和ASPM均为不良预后基因,分别在SPP1阳性巨噬细胞和MKI67阳性巨噬细胞中特异性表达并发挥负性免疫调节作用,进而促进PDAC的进展并导致不良预后,这有望为PDAC的防治提供新的靶点。 展开更多
关键词 胰腺导管腺癌 巨噬细胞 预后 肿瘤微环境 单细胞测序 拟时序分析 2'-5'-寡腺苷酸合成酶2
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Perilipin-2 mediates ferroptosis in oligodendrocyte progenitor cells and myelin injury after ischemic stroke 被引量:2
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作者 Jian Yang Jiang Wu +7 位作者 Xueshun Xie Pengfei Xia Jinxin Lu Jiale Liu Lei Bai Xiang Li Zhengquan Yu Haiying Li 《Neural Regeneration Research》 SCIE CAS 2025年第7期2015-2028,共14页
Differentiation of oligodendrocyte progenitor cells into mature myelin-forming oligodendrocytes contributes to remyelination.Failure of remyelination due to oligodendrocyte progenitor cell death can result in severe n... Differentiation of oligodendrocyte progenitor cells into mature myelin-forming oligodendrocytes contributes to remyelination.Failure of remyelination due to oligodendrocyte progenitor cell death can result in severe nerve damage.Ferroptosis is an iron-dependent form of regulated cell death caused by membrane rupture induced by lipid peroxidation,and plays an important role in the pathological process of ischemic stroke.However,there are few studies on oligodendrocyte progenitor cell ferroptosis.We analyzed transcriptome sequencing data from GEO databases and identified a role of ferroptosis in oligodendrocyte progenitor cell death and myelin injury after cerebral ischemia.Bioinformatics analysis suggested that perilipin-2(PLIN2)was involved in oligodendrocyte progenitor cell ferroptosis.PLIN2 is a lipid storage protein and a marker of hypoxia-sensitive lipid droplet accumulation.For further investigation,we established a mouse model of cerebral ischemia/reperfusion.We found significant myelin damage after cerebral ischemia,as well as oligodendrocyte progenitor cell death and increased lipid peroxidation levels around the infarct area.The ferroptosis inhibitor,ferrostatin-1,rescued oligodendrocyte progenitor cell death and subsequent myelin injury.We also found increased PLIN2 levels in the peri-infarct area that co-localized with oligodendrocyte progenitor cells.Plin2 knockdown rescued demyelination and improved neurological deficits.Our findings suggest that targeting PLIN2 to regulate oligodendrocyte progenitor cell ferroptosis may be a potential therapeutic strategy for rescuing myelin damage after cerebral ischemia. 展开更多
关键词 BIOINFORMATICS bulk RNA sequencing ferroptosis ischemic stroke myelin injury oligodendrocyte progenitor cell perilipin-2 single-cell RNA sequencing
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蚕豆萎蔫病毒2根芹分离物全基因组测序与分析 被引量:1
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作者 郭孟泽 尹任 +4 位作者 孙平平 张磊 李文彪 郑莎 李正男 《山西农业大学学报(自然科学版)》 北大核心 2025年第1期21-28,共8页
[目的]获取蚕豆萎蔫病毒2(broad bean wilt virus 2,BBWV 2)内蒙古根芹(Apium graveolens var.rapaceum)分离物全基因组序列,并将该基因组序列与其它BBWV 2分离物基因组序列进行一致性、系统发育及重组等分析。[方法]以疑似感染病毒的... [目的]获取蚕豆萎蔫病毒2(broad bean wilt virus 2,BBWV 2)内蒙古根芹(Apium graveolens var.rapaceum)分离物全基因组序列,并将该基因组序列与其它BBWV 2分离物基因组序列进行一致性、系统发育及重组等分析。[方法]以疑似感染病毒的根芹叶片样品为试验材料,利用NGS技术确定样品中感染病毒的种类,通过RT-PCR技术结合cDNA末端快速扩增技术(Rapid amplification of cDNA ends,RACE)验证病毒种类,使用VectorNTI、MEGA11、SDTV1.2以及RDP4等软件对克隆到的BBWV 2内蒙古根芹分离物20IM-ApGr进行全基因组序列分析。[结果]成功克隆了BBWV 2内蒙古根芹分离物20IM-ApGr两条RNA的完整序列;序列一致性分析结果显示,20IM-ApGr与其它分离物在Pro-RdRp区域和CPs区域的氨基酸序列一致率分别为85.2%~99.5%和82.8%~92.7%;基于BBWV 2基因组的Pro-RdRp区域和CPs区域所构建的系统发育树均可以将目前已知的BBWV 2分离物分为2个分支,其中本研究所获得的分离物均处于第II分支,并分别与中国辣椒分离物Hunan、XJ14-3亲缘关系最近。[结论]明确了造成根芹叶脉黄化以及叶片皱缩的病毒性病原为BBWV2,首次获得BBWV 2内蒙古根芹分离物的全基因组序列,并阐述了其与已知的BBWV 2分离物之间的进化关系,可为BBWV 2株系划分、遗传进化研究奠定理论基础。 展开更多
关键词 根芹 蚕豆萎蔫病毒2 序列一致性 系统发育分析
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Whole-genome sequencing identifies functional genes for environmental adaptation in Chinese sheep
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作者 Yinan Niu Yefang Li +5 位作者 Yuhetian Zhao Xiaohong He Qianjun Zhao Yabin Pu Yuehui Ma Lin Jiang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2024年第11期1278-1285,共8页
Sheep(Ovis aries),among the first domesticated species,are now globally widespread and exhibit remarkable adaptability to diverse environments.In this study,we perform whole-genome sequencing of266 animals from 18 dis... Sheep(Ovis aries),among the first domesticated species,are now globally widespread and exhibit remarkable adaptability to diverse environments.In this study,we perform whole-genome sequencing of266 animals from 18 distinct Chinese sheep populations,each displaying unique phenotypes indicative of adaptation to varying environmental conditions.Integrating 131 environmental factors with single nucleotide polymorphism variations,we conduct a comprehensive genetic-environmental association analysis.This analysis identifies 35 key genes likely integral to the environmental adaptation of sheep.The functions of these genes include fat tail formation(HOXA10,HOXA11,JAZF1),wool characteristics(FER,FGF5,MITF,PDE4B),horn phenotypes(RXFP2),reproduction(HIBADH,TRIM71,C6H4orf22),and growth traits(ADGRL3,TRHDE).Notably,we observe a significant correlation between the frequency of missense mutations in the PAPSS2 and RXFP2 genes and variations in altitude.Our study reveals candidate genes for adaptive variation in sheep and demonstrates the diversity in how sheep adapt to their environment. 展开更多
关键词 Whole-genome sequencing Local adaptation PAPSS2 RXFP2 Missense variant
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Recent advances and perspectives in next generation sequencing application to the genetic research of type 2 diabetes 被引量:3
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作者 Yulia A Nasykhova Yury A Barbitoff +2 位作者 Elena A Serebryakova Dmitry S Katserov Andrey S Glotov 《World Journal of Diabetes》 SCIE CAS 2019年第7期376-395,共20页
Type 2 diabetes(T2D)mellitus is a common complex disease that currently affects more than 400 million people worldwide and has become a global health problem.High-throughput sequencing technologies such as whole-genom... Type 2 diabetes(T2D)mellitus is a common complex disease that currently affects more than 400 million people worldwide and has become a global health problem.High-throughput sequencing technologies such as whole-genome and whole-exome sequencing approaches have provided numerous new insights into the molecular bases of T2D.Recent advances in the application of sequencing technologies to T2D research include,but are not limited to:(1)Fine mapping of causal rare and common genetic variants;(2)Identification of confident genelevel associations;(3)Identification of novel candidate genes by specific scoring approaches;(4)Interrogation of disease-relevant genes and pathways by transcriptional profiling and epigenome mapping techniques;and(5)Investigation of microbial community alterations in patients with T2D.In this work we review these advances in application of next-generation sequencing methods for elucidation of T2D pathogenesis,as well as progress and challenges in implementation of this new knowledge about T2D genetics in diagnosis,prevention,and treatment of the disease. 展开更多
关键词 Type 2 diabetes Next-generation sequencing EPIGENETICS GENOME-WIDE association study MICROBIOME
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Phylogenetic, phylogeographic and divergence time analysis of Anopheles subpictus species complex using ITS2 and COI sequences
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作者 Lihini Sandaleka Muthukumarana Methsala Madurangi Wedage +1 位作者 Samanthika Rathnayake Nissanka Kolitha De Silva 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第5期214-225,I0004-I0038,共47页
Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Tran... Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Transcriber Spacer 2(ITS2)and cytochrome C oxidase I(COI)sequences deposited at the GenBank.Methods:Seventy-five ITS2,210 COI and 26 concatenated sequences available in the NCBI database were used.Phylogenetic analysis was performed using Bayesian likelihood trees,whereas median-joining haplotype networks and time-scale divergence trees were generated for phylogeographic analysis.Genetic diversity indices and genetic differentiation were also calculated.Results:Two genetically divergent molecular forms of An.subpictus species complex corresponding to sibling species A and B are established.Species A evolved around 37-82 million years ago in Sri Lanka,India,and the Netherlands,and species B evolved around 22-79 million years ago in Sri Lanka,India,and Myanmar.Vietnam,Thailand,and Cambodia have two molecular forms:one is phylogenetically similar to species B.Other forms differ from species A and B and evolved recently in the above mentioned countries,Indonesia and the Philippines.Genetic subdivision among Sri Lanka,India,and the Netherlands is almost absent.A substantial genetic differentiation was obtained for some populations due to isolation by large geographical distances.Genetic diversity indices reveal the presence of a long-established stable mosquito population,at mutation-drift equilibrium,regardless of population fluctuations.Conclusions:An.subpictus species complex consists of more than two genetically divergent molecular forms.Species A is highly divergent from the rest.Sri Lanka and India contain only species A and B. 展开更多
关键词 Molecular systematics ITS2 COI DNA sequences Phylogeny PHYLOGEOGRAPHY
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基于ITS2和psbA-trnH序列鉴别五味子和华中五味子 被引量:1
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作者 杨楚楚 任广喜 +6 位作者 齐玉鑫 徐庆一 田俊强 程豪杰 陈晓洲 姜丹 刘春生 《中国现代中药》 2025年第1期43-51,共9页
目的:基于核内转录间隔区2(ITS2)和psbA-trnH序列,运用DNA条形码技术对五味子和华中五味子进行序列比对分析,建立快速、准确的分子鉴定方法,筛选最佳DNA条形码序列用于鉴别五味子和华中五味子真伪。方法:以五味子和华中五味子为材料,利... 目的:基于核内转录间隔区2(ITS2)和psbA-trnH序列,运用DNA条形码技术对五味子和华中五味子进行序列比对分析,建立快速、准确的分子鉴定方法,筛选最佳DNA条形码序列用于鉴别五味子和华中五味子真伪。方法:以五味子和华中五味子为材料,利用DNA提取试剂盒,分别提取五味子和华中五味子的总DNA,对ITS2序列和psbA-trnH序列进行聚合酶链式反应扩增及测序分析,使用DNAMAN 6.0软件统计其片段长度及变异位点个数,使用MEGA 5.0软件对数据进行分析比对,计算Kimura 2-parameter遗传距离,通过数据库预测二级结构,并利用邻接法建立系统发育树进行分析。结果:五味子和华中五味子ITS2序列片段长度为231 bp,鉴别位点为腺嘌呤(A)-胸腺嘧啶(T)、鸟嘌呤(G)-T、T-A;在psbA-trnH序列中,存在7个稳定的鉴别位点,分别为GA、T-G、胞嘧啶(C)-A、T-A、缺失-T、A-T、G-T,五味子和华中五味子ITS2序列二级结构存在明显差异,能将两者进行区分。结论:ITS2和psbA-trnH条形码均可以用于区分五味子和华中五味子,但psbA-trnH条形码种内遗传更稳定,种间鉴别位点更多,研究为五味子和华中五味子的快速、准确鉴定和用药安全提供科学依据。 展开更多
关键词 五味子 华中五味子 DNA条形码 内转录间隔区2序列 叶绿体基因间隔区序列
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丽江猪HMOX 2基因扩增、序列分析及组织表达研究
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作者 李天秀 李昕鹏 +3 位作者 董新星 兰国湘 严达伟 朱家位 《中国畜牧兽医》 北大核心 2025年第5期2219-2231,共13页
【目的】旨在扩增并探究丽江猪血红素加氧酶2(HMOX2)基因编码区(CDS)序列特征,分析在丽江猪不同生长阶段、不同组织中的表达情况,为利用HMOX 2基因进行分子标记辅助育种奠定基础。【方法】利用PCR扩增丽江猪HMOX 2基因序列,采用生物信... 【目的】旨在扩增并探究丽江猪血红素加氧酶2(HMOX2)基因编码区(CDS)序列特征,分析在丽江猪不同生长阶段、不同组织中的表达情况,为利用HMOX 2基因进行分子标记辅助育种奠定基础。【方法】利用PCR扩增丽江猪HMOX 2基因序列,采用生物信息学软件分析其理化性质和密码子偏好性,预测其蛋白结构;采用实时荧光定量PCR检测HMOX 2基因在2月龄丽江猪心脏、肝脏、脾脏、肺脏、肾脏和背最长肌,以及2、4、6月龄丽江猪皮下脂肪中的表达水平,并对HMOX 2基因在2月龄丽江猪和杜洛克猪皮下脂肪中的表达水平进行比较分析。【结果】丽江猪HMOX 2基因CDS序列长为951 bp,编码316个氨基酸,密码子偏好以C或G结尾。丽江猪HMOX 2基因与黄牛、水牛、山羊和绵羊的相似性较高(90.1%~91.2%),与原鸡的相似性最低(71.3%)。在6个地方猪种中,除八眉猪和荣昌猪外,丽江猪HMOX 2基因与中国地方猪相似性为100%,与5个外种猪的相似性均为99.8%。与杜洛克猪相比,丽江猪HMOX 2基因CDS区存在两处碱基同义突变。HMOX2蛋白属于稳定的跨膜亲水性蛋白,无信号肽,具有1个跨膜结构,主要在细胞质中发挥作用,含21个磷酸化位点和33个糖基化位点。二级结构主要由α-螺旋(54.43%)和无规则卷曲(42.00%)组成。蛋白互作网络分析表明,HMOX2蛋白可能与FECH、HMOX1等10个蛋白互作,主要在脂质代谢中发挥作用。实时荧光定量PCR结果表明,HMOX 2基因在丽江猪心脏、肝脏、脾脏、肺脏、肾脏、背最长肌和皮下脂肪中均有表达,且在皮下脂肪中随月龄增长表达量增加。与杜洛克猪相比,丽江猪HMOX 2基因在皮下脂肪中的表达量显著高于杜洛克猪(P<0.05)。【结论】本研究成功扩增了丽江猪HMOX 2基因并分析了其分子特征,其在肺脏、肝脏和皮下脂肪等7个组织中均有表达,在皮下脂肪组织中随月龄增长表达量显著增加。研究结果可为进一步探究HMOX 2基因在丽江猪脂肪沉积中的作用奠定基础。 展开更多
关键词 丽江猪 血红素加氧酶2基因 序列分析 组织表达
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Landscape of Sequence Variations in Homologous Copies of FAD2 and FAD3 in Rapeseed(Brassica napus L.)Germplasm with High/Low Linolenic Acid Trait
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作者 Haoxue Wu Xiaohan Zhang +5 位作者 Xiaoyu Chen Kang Li Aixia Xu Zhen Huang Jungang Dong Chengyu Yu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期627-640,共14页
Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har... Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil accumulation.In this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype ZS11.The expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and SW.The three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and BnFAD3.A3.In A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were detected.The profile of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous studies.The mutations in BnFAD3 in the high-ALA accessions are reported for thefirst time.In identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes. 展开更多
关键词 Brassica napus linolenic acid FAD2 FAD3 promoter coding sequences mutation
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Novel mutations in CRYBB1/CRYBB2 identified by targeted exome sequencing in Chinese families with congenital cataract 被引量:2
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作者 Peng Chen Hao Chen +3 位作者 Xiao-Jing Pan Su-Zhen Tang Yu-Jun Xia Hui Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第10期1577-1582,共6页
AIM:To summarize the phenotypes and identify the underlying genetic cause of the CRYBB1 and CRYBB2 gene responsible for congenital cataract in two Chinese families.METHODS:Detailed family histories and clinical data... AIM:To summarize the phenotypes and identify the underlying genetic cause of the CRYBB1 and CRYBB2 gene responsible for congenital cataract in two Chinese families.METHODS:Detailed family histories and clinical data were collected from patients during an ophthalmologic examination. Of 523 inheritable genetic vision systemrelated genes were captured and sequenced by targeted next-generation sequencing,and the results were confirmed by Sanger sequencing. The possible functional impacts of an amino acid substitution were performed with Poly Phen-2 and SIFT predictions.RESULTS:The patients in the two families were affected with congenital cataract. Sixty-five (FAMILY-1) and sixty two (FAMILY-2) single-nucleotide polymorphisms and indels were selected by recommended filtering criteria.Segregation was then analyzed by applying Sanger sequencing with the family members. A heterozygous CRYBB1 mutation in exon 4 (c.347T〉C, p.L116P) was identified in sixteen patients in FAMILY-1. A heterozygous CRYBB2 mutation in exon 5 (c.355G〉A, p.G119R) was identified in three patients in FAMILY-2. Each mutation cosegregated with the affected individuals and did not exist in unaffected family members and 200 unrelated normal controls.The mutation was predicted to be highly conservative and to be deleterious by both PolyPhen-2 and SIFT.CONCLUSION:TheCRYBB1 mutation(c.347T〉C)and CRYBB2 mutation (c.355G〉A) are novel in patients with congenital cataract. We summarize the variable phenotypes among the patients, which expanded the phenotypic spectrum of congenital cataract in a different ethnic background. 展开更多
关键词 CRYBB1 CRYBB2 next-generation sequencing congenital cataract
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