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Exploring the impact of envelope protein mutations on Chikungunya virus epitopes:Analysis of virus samples from the Alagoas State outbreak,Brazil
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作者 Jamile Taniele-Silva Júlia De Andrade Brandão +6 位作者 Maria Júlia Tenório Costa Cinésio De Oliveira Stephannie Janaina Maia De Souza Jean Fábio Gomes Ferro Magliones Carneiro De Lima Abelardo Silva-Júnior Ênio JoséBassi Letícia Anderson 《Asian Pacific Journal of Tropical Medicine》 2025年第6期269-279,共11页
Objective:To investigate mutations in the Chikungunya(CHIKV)envelope genome region and evaluate their potential impact on B lymphocyte epitopes via in silico analysis.Methods:E1,E2 and 6K protein genes were sequenced ... Objective:To investigate mutations in the Chikungunya(CHIKV)envelope genome region and evaluate their potential impact on B lymphocyte epitopes via in silico analysis.Methods:E1,E2 and 6K protein genes were sequenced from viral RNA isolated from 13 CHIKV-positive serum samples from Alagoas State,Brazil,during the 2016 outbreak.Phylogenetic analysis,experimental epitope identification in the immune epitope database(IEDB)and in silico approaches were employed to predict the potential impact of the detected mutations.Results:The sequences were clustered via phylogenetic analysis.The CHIKV isolates belong to the ECSA genotype,with 13 detected amino acid mutations.Five mutations are located on the surface of the viral particle in regions critical for cellular receptor interaction.Nine mutations are known experimentally validated epitopes for B and T cells.In B-cell epitope predictions,mutations affect sequences within three conformational epitopes in E2 and one in E1,as well as linear epitopes.Notably,the E2-G60D mutation found in the Alagoas strain has been previously reported to influence the vector competence of Aedes aegypti,the primary vector in Brazil.Conclusions:Genomic surveillance and an in-depth understanding of viral mutations are crucial for adapting public health strategies and improving the outbreak response.These findings could have significant public health implications,such as the development of more effective vaccines,diagnostic tests,and antiviral therapies. 展开更多
关键词 Genomic variations In silico analysis Epitope prediction Glycoprotein mutations
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Comprehensive analysis of gene mutations and mismatch repair in Chinese colorectal cancer patients
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作者 Huang Chen Rui-Ying Jiang +11 位作者 Zhan Hua Xiao-Wei Wang Xiao-Li Shi Ye Wang Qian-Qian Feng Jie Luo Wu Ning Yan-Fen Shi Da-Kui Zhang Bei Wang Jian-Zheng Jie Ding-Rong Zhong 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2673-2682,共10页
BACKGROUND RAS,BRAF,and mismatch repair(MMR)/microsatellite instability(MSI)are crucial biomarkers recommended by clinical practice guidelines for colorectal cancer(CRC).However,their characteristics and influencing f... BACKGROUND RAS,BRAF,and mismatch repair(MMR)/microsatellite instability(MSI)are crucial biomarkers recommended by clinical practice guidelines for colorectal cancer(CRC).However,their characteristics and influencing factors in Chinese patients have not been thoroughly described.AIM To analyze the clinicopathological features of KRAS,NRAS,BRAF,and PIK3CA mutations and the DNA MMR status in CRC.METHODS We enrolled 2271 Chinese CRC patients at the China-Japan Friendship Hospital.MMR proteins were tested using immunohistochemical analysis,and the KRAS/NRAS/BRAF/PIK3CA mutations were determined using quantitative polymerase chain reaction.Microsatellite status was determined using an MSI detection kit.Statistical analyses were conducted using SPSS software and logistic regression.RESULTS The KRAS,NRAS,BRAF,and PIK3CA mutations were detected in 44.6%,3.4%,3.7%,and 3.9% of CRC patients,respectively.KRAS mutations were more likely to occur in patients with moderate-to-high differentiation.BRAF mutations were more likely to occur in patients with right-sided CRC,poorly differentiated,or no perineural invasion.Deficient MMR(dMMR)was detected in 7.9% of all patients and 16.8% of those with mucinous adenocarcinomas.KRAS,NRAS,BRAF,and PIK3CA mutations were detected in 29.6%,1.1%,8.1%,and 22.3% of patients with dMMR,respectively.The dMMR was more likely to occur in patients with a family history of CRC,aged<50 years,right-sided CRC,poorly differentiated histology,no perineural invasion,and with carcinoma in situ,stage I,or stage II tumors.CONCLUSION This study analyzed the molecular profiles of KRAS,NRAS,BRAF,PIK3CA,and MMR/MSI in CRC,identifying key influencing factors,with implications for clinical management of CRC. 展开更多
关键词 Colorectal cancer Deficient mismatch repair Microsatellite instability Gene mutation Comprehensive analysis
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Temperature Variation and Mutation Analysis over the Past 59 Years in Shenyang 被引量:1
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作者 王明华 孙晓巍 +1 位作者 李广霞 戴廷仁 《Meteorological and Environmental Research》 CAS 2010年第11期33-35,39,共4页
In this paper,based on the observation data of air temperature during 1951-2009 in Shenyang,the interannual and interdecadal variation of annual average temperature,maximum and minimum temperature in Shenyang were con... In this paper,based on the observation data of air temperature during 1951-2009 in Shenyang,the interannual and interdecadal variation of annual average temperature,maximum and minimum temperature in Shenyang were conducted the statistical analysis by means of linear trend estimation and mutation detection by using Mann-Kendall method.As was demonstrated in the results,the annual average temperature,maximum and minimum temperature in Shenyang showed an upward trend,whose linear tendency rate was 0.231,0.181 and 0.218 respectively.The increment trend of annual average temperature,maximum and minimum temperature was extremely clear.The increase in minimum temperature was more significant than that in mean temperature and maximum temperature.The abrupt change point of annual mean temperature in Shenyang appeared in 1981;the abrupt change point of annual mean maximum temperature appeared in 1994;the annual mean minimum temperature underwent mutation in 1978. 展开更多
关键词 Shenyang Temperature variation mutation analysis Mann-Kendall statistical test China
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Climate change and human activities on runoff in northern Shaanxi:Based on Budyko framework analysis
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作者 ZHANG Lin JIANG Xiaohui +1 位作者 XU Fangbing YANG Anle 《Journal of Geographical Sciences》 2025年第5期979-1002,共24页
Studying runoff characteristics and quantifying human activities’impact on northern Shaanxi,a crucial mineral resource area in China,is crucial to alleviate water resource contradictions.In this study,hydrological el... Studying runoff characteristics and quantifying human activities’impact on northern Shaanxi,a crucial mineral resource area in China,is crucial to alleviate water resource contradictions.In this study,hydrological element trends were analyzed using theβ-z-h three-parameter indication method.The Mann-Kendall,Pettitt,moving T,and Yamamoto methods were used to test the mutation point of hydrological elements.The Budyko framework was used to quantitatively assess the impacts of climate change and multiple human activities on runoff reduction.The results showed that(1):Precipitation(PRE),potential evapotranspiration(E0),and temperature(TEM)showed increasing trends;runoff in the Huangfuchuan,Gushanchuan,Kuye River,Tuwei River,Wuding River,Qingjian River,and Yanhe River catchments showed decreasing trends(HFC,GSC,KYR,TWR,WDR,QJR,YR);whereas runoff in the Jialu River(JLR)catchment showed a“V-shaped”trend from 1980 to2020.(2)Runoff was positively correlated with PRE and negatively correlated with E0and the subsurface index(n),with the elasticity coefficients of PRE,E0,and n showing an increasing trend in the change period.(3)Human activities were a key factor in runoff reduction,although the impact of different human activities showed spatial variations.This study provides a scientific foundation for achieving the sustainable development of water resources in mining areas. 展开更多
关键词 hydrological elements trend analysis mutation points Budyko framework attribution analysis mining areas northern Shaanxi
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Deciphering lactate metabolism in colorectal cancer:Prognostic modeling,immune infiltration,and gene mutation insights
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作者 Xiao-Peng Wang Jia-Xin Zhu +5 位作者 Chang Liu Hao-Wen Zhang Guan-Duo Sun Jing-Ming Zhai Hai-Jun Yang De-Chun Liu 《World Journal of Gastroenterology》 2025年第25期70-90,共21页
BACKGROUND Colorectal cancer(CRC)remains a major global health burden due to its high incidence and mortality,with treatment efficacy often hindered by tumor hetero-geneity,drug resistance,and a complex tumor microenv... BACKGROUND Colorectal cancer(CRC)remains a major global health burden due to its high incidence and mortality,with treatment efficacy often hindered by tumor hetero-geneity,drug resistance,and a complex tumor microenvironment(TME).Lactate metabolism plays a pivotal role in reshaping the TME,promoting immune eva-sion and epithelial-mesenchymal transition,making it a promising target for novel therapeutic strategies and prognostic modeling in CRC.AIM To offer an in-depth analysis of the role of lactate metabolism in CRC,high-lighting its significance in the TME and therapeutic response.METHODS Utilizing single-cell and transcriptomic data from the Gene Expression Omnibus and The Cancer Genome Atlas,we identified key lactate metabolic activities,particularly in the monocyte/macrophage subpopulation.RESULTS Seven lactate metabolism-associated genes were significantly linked to CRC prognosis and used to construct a predictive model.This model accurately forecasts patient outcomes and reveals notable distinct patterns of immune infiltration and transcriptomic profiles mutation profiles between high-and low-risk groups.High-risk patients demonstrated elevated immune cell infiltration,increased mutation frequencies,and heightened sensitivity to specific drugs(AZD6482,tozasertib,and SB216763),providing a foundation for personalized treatment approaches.Additionally,a nomogram integrating clinical and metabolic data effectively predicted 1-,3-,and 5-year survival rates.CONCLUSION This report underscored the pivotal mechanism of lactate metabolism in CRC prognosis and suggest novel avenues for therapeutic intervention. 展开更多
关键词 Colorectal cancer Lactate metabolism Prognostic model Immune infiltration Gene mutation analysis
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Novel ATOH7 mutation and structural characterization in families with optic nerve hypoplasia
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作者 Muhammad Ikram Ullah Rubina Dad +7 位作者 Zaira Rehman Muhammad Shakil Abdullah Alsrhani Ayman Ali Mohammed Alameen Heba Bassiony Ghanem Emad Manni Muhammad Umer Khan Muhammad Atif 《International Journal of Ophthalmology(English edition)》 2025年第9期1705-1712,共8页
AIM:To detect and segregate causative mutations in congenital families with optic nerve hypoplasia(ONH).M E T H O D S:Two unrel a ted consanguineous Pakistani families with severe ONH,showing features of micropthalmia... AIM:To detect and segregate causative mutations in congenital families with optic nerve hypoplasia(ONH).M E T H O D S:Two unrel a ted consanguineous Pakistani families with severe ONH,showing features of micropthalmia,nystagmus,corneal opacity,and keratopathy were included.Genetic analysis was carried out by Target Panel Sequencing,and the nucleotide variant was confirmed by Sanger sequencing.In silico analyses were carried out to study the protein order-disorder functions and their effects on messenger ribonucleic acid(mRNA).RESULTS:Target panel sequencing revealed that the afflicted family members carried a novel frameshift mutation(NM_145178.4;c.91del G;p.Gly31Glyfs*55)that ensued in the conservation of an amino acid residue in the bHLH domain of ATOH7 protein.In silico studies predicted that the activity of the ATOH7 gene is probably affected by this mutation,which results in a shortened and nonfunctional protein.Three-dimensional structural analysis shows that DNA binding may be impacted by amino acid changes from non-polar to positively charged and vice versa(Arg42Pro and Pro18Arg),as well as from positively charged(Arg)to a small polar amino acid(Gly).CONCLUSION:A novel ATOH7 mutation is harmful.This study also emphasizes the potential effects of modified ATOH7 configurations on the stability and functionality of proteins. 展开更多
关键词 optic nerve hypoplasia congenital families ATOH7 gene novel mutation disorder protein structural analysis
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Atypical case of Rett syndrome with concurrent MECP2 gene mutation and del(15)(q22qter)karyotype:A case report and review of literature
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作者 Imad Fadl-Elmula Sara Y Abdel-Raheem Rayan Khalid 《World Journal of Clinical Pediatrics》 2025年第4期516-522,共7页
BACKGROUND Rett syndrome is a monogenic X-linked dominant condition that affects 1/(10000-15000)girls due to de novo mutations in the methyl-CpG binding protein 2(MECP2)gene mapped to chromosome Xq28.The disease-causi... BACKGROUND Rett syndrome is a monogenic X-linked dominant condition that affects 1/(10000-15000)girls due to de novo mutations in the methyl-CpG binding protein 2(MECP2)gene mapped to chromosome Xq28.The disease-causing gene was identified as a mutation in the MECP2 gene,which is found in approximately 80%of patients diagnosed with Rett syndrome.Although chromosomal changes resulting in del(15)(q11q13)are usually associated with Angelman and Prader-Willi syndrome,very few cases,if any,of Rett syndrome with terminal 15q22-qter deletion have been published in English literature.CASE SUMMARY In this study,we report an unusual and rare clinical presentation of Rett syndrome in a 12-year-old Sudanese girl.The patient was brought in by her parents,complaining of gradual onset of abnormal walking,abnormal hand movement,loss of speech,and mental retardation for ten years.There was no reported history of convulsions or loss of consciousness.Clinical examination revealed microcephaly with no other apparent dysmorphic features,intact cranial nerves,and abnormal gait.She showed repetitive and stereotyped behaviors,including hand flapping,stimming,and chest pounding,which were concomitant with autism spectrum disorder.Magnetic resonance imaging and electroencephalography investigations were normal,and cytogenetic analysis showed 46,XX,del(15)(q22qter).Further molecular analysis using whole sequencing of MECP2 revealed an alteration cytosine>thymine at nucleotide 401,leading to phenylalanine replacing a serine at amino acid position 134.CONCLUSION This case,the first reported instance of Rett syndrome in Sudan,is of significant interest.The patient carries both the MECP2 gene mutation and the chromosome 15q22-qter deletion,which may explain the autistic behavior with atypical presentation of Rett syndrome.This report expands the genetic diversity of Rett syndrome,demonstrating how co-occurring 15q22-qter deletions can reshape MECP2-associated phenotypes in Rett syndrome. 展开更多
关键词 Rett syndrome Autism spectrum disorder Methyl-CpG-binding protein two gene mutation Chromosome 15 deletion Atypical presentation Chromosomal analysis Case report
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Comparative analysis of dideoxy sequencing,the KRAS StripAssay and pyrosequencing for detection of KRAS mutation 被引量:8
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作者 Jing Gao Yan-Yan Li +1 位作者 Ping-Nai Sun Lin Shen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第38期4858-4864,共7页
AIM:To compare the differences between dideoxy sequencing/KRAS StripAssay/pyrosequencing for detection of KRAS mutation in Chinese colorectal cancer (CRC) patients.METHODS:Formalin-f ixed, paraff in-embedded (FFPE) sa... AIM:To compare the differences between dideoxy sequencing/KRAS StripAssay/pyrosequencing for detection of KRAS mutation in Chinese colorectal cancer (CRC) patients.METHODS:Formalin-f ixed, paraff in-embedded (FFPE) samples with tumor cells ≥ 50% were collected from 100 Chinese CRC patients at Beijing Cancer Hospital. After the extraction of genome DNA from FFPE samples, fragments contained codons 12 and 13 of KRAS exon 2 were amplified by polymerase chain reaction and analyzed by dideoxy sequencing, the KRAS Strip Assay and pyrosequencing. In addition, the sensitivities of the 3 methods were compared on serial dilutions (contents of mutant DNA: 100%,50%,20%, 5%,10%, 5%,1%,0%) of A549 cell line DNA (carrying the codon 12 Gly>Ser mutation) into wild-type DNA (human normal intestinal mucosa). The results of dideoxy sequencing,the KRAS StripAssay and pyrosequencing were analyzed by Chromas Software, Collector forKRAS Strip Assay and the pyrosequencing PyroMarkTM Q24 system, respectively.RESULTS: Among 100 patients, KRAS mutations were identif ied in 34%, 37% and 37% of patients by dideoxy sequencing, the KRAS StripAssay and pyrosequencing, respectively. The sensitivity was highest with the KRAS Strip Assay (1%), followed by pyrosequencing (5%), and dideoxy sequencing was lowest (15%). Six different mutation types were found in this study with 3 main mutations Gly12 Asp (GGT>GAT), Gly12 Val (GGT>GTT) and Gly13 Asp (GGC>GAC). Thirty-three patients were identifi ed to have KRAS mutations by the 3 methods, and a total of 8 patients had conflicting results between 3 methods: 4 mutations not detected by dideoxy sequencing and the KRAS StripAssay were identified by pyrosequencing; 3 mutations not detected by dideoxy sequencing and pyrosequencing were identif ied by the KRAS StripAssay; and 1 mutation not detected by pyrosequencing was conf irmed by dideoxy sequencing and the KRAS StripAssay. Among these discordant results, the results identif ied by dideoxy sequencing were consistent either with the KRAS StripAssay or with pyrosequencing, which indicated that the accuracy of dideoxy sequencing was high. CONCLUSION: Taking a worldwide view of reports and our results,dideoxy sequencing remains the most popular method because of its low cost and high accuracy. 展开更多
关键词 DNA mutational analysis KRAS mutation Dideoxy sequencing KRAS StripAssay PYROSEQUENCING
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Clinical classification and gene mutation of Chinese probands with Charcot-Marie-Tooth disease Analysis of 57 cases 被引量:4
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作者 Ruxu Zhang Xiaobo Li +5 位作者 Xiaohong Zi Shunxiang Huang Fufeng Zhang Kun Xia Qian Pan Beisha Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第9期706-711,共6页
Charcot-Marie-Tooth (CMT) disease is the most common inherited peripheral neuropathic disorder. CMT is clinically and genetically heterogeneous. To date, 27 genes associated with the disease have been cloned. The pr... Charcot-Marie-Tooth (CMT) disease is the most common inherited peripheral neuropathic disorder. CMT is clinically and genetically heterogeneous. To date, 27 genes associated with the disease have been cloned. The present study carried out clinical classification according to clinical, electrophysiological and pathological features, conducted inheritance classification according to inheritance patterns, and performed mutation analysis of 13 CMT disease genes (PMP22, CX32, HSPB1, MNF2, MPZ, HSPB8, GDAP1, NFL, EGR2, SIMPLE, RAB7, LMNA, MTMR2) in 57 Chinese probands with CMT. Five cases of AD-CMT1 and 13 cases of sporadic CMT1 were diagnosed as CMT1A; five cases of X-CMT1, one case of X-CMT2 and one case of sporadic CMT1 were diagnosed as CMTXl; four cases of AD-CMT2 were diagnosed as CMT2F; one case of AD-CMT2 and one case of sporadic CMT2 were diagnosed as CMT2A2; one case of AD-CMT2 was diagnosed as CMT2L; one case of AD-CMT2 was diagnosed as CMT2J; one case of AR-CMT1 was diagnosed as CMT4A. Among the 57 CMT probands, seven genotypes were determined among 34 patients, with a detection rate of 59.6%. The results indicated that the clinical classification and inheritance classification are indispensable for selecting potential disease genes for mutation detection, and for efficient molecular diagnosis. 展开更多
关键词 Charcot-Marie-Tooth disease clinical classification GENE mutation analysis
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Analysis of correlated mutations, stalk motifs, and phylogenetic relationship of the 2009 influenza A virus neuraminidase sequences 被引量:4
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作者 Wei Hu 《Journal of Biomedical Science and Engineering》 2009年第7期550-558,共9页
The 2009 H1N1 influenza pandemic has attracted worldwide attention. The new virus first emerged in Mexico in April, 2009 was identified as a unique combination of a triple- reassortant swine influenza A virus, compose... The 2009 H1N1 influenza pandemic has attracted worldwide attention. The new virus first emerged in Mexico in April, 2009 was identified as a unique combination of a triple- reassortant swine influenza A virus, composed of genetic information from pigs, hu- mans, birds, and a Eurasian swine influenza virus. Several recent studies on the 2009 H1N1 virus util-ized small datasets to conduct analysis. With new sequences available up to date, we were able to extend the previous research in three areas. The first was finding two networks of co-mutations that may po-tentially affect the current flu-drug binding sites on neuraminidase (NA), one of the two surface proteins of flu virus. The second was discovering a special stalk motif, which was dominant in the H5N1 strains in the past, in the 2009 H1N1 strains for the first time. Due to the high virulence of this motif, the second finding is significant in our current research on 2009 H1N1. The third was updating the phylogenetic an- alysis of current NA sequences of 2009 H1N1 and H5N1, which demonstrated that, in clear contrast to previous findings, the N1 sequences in 2009 are di-verse enough to cover different major branches of the phylogenetic tree of those in previous years. As the novel influenza A H1N1 virus continues to spread globally, our results highlighted the importance of performing timely analysis on the 2009 H1N1 virus. 展开更多
关键词 Entropy Co-mutation mutation Mutual Information NEURAMINIDASE Phylogenetic analysis Random Forest STALK Motif Swine Flu
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Is exon mutation analysis needed for adjuvant treatment of gastrointestinal stromal tumor? 被引量:1
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作者 Mehmet Ali Nahit Sendur Nuriye Yildirim zdemir +3 位作者 Muhammed Bülent Akinci Dogan Uncu Nurullah Zengin Sercan Aksoy 《World Journal of Gastroenterology》 SCIE CAS 2013年第1期144-146,共3页
Gastrointestinal stromal tumors(GISTs) are the most common soft tissue sarcoma of the gastrointestinal tract,resulting from an activating mutation of stem cell factor receptor(KIT),and an activating mutation of the ho... Gastrointestinal stromal tumors(GISTs) are the most common soft tissue sarcoma of the gastrointestinal tract,resulting from an activating mutation of stem cell factor receptor(KIT),and an activating mutation of the homologous platelet-derived growth factor receptor alpha(PDGFRA) kinase.Most GISTs(90%-95%) are KIT-positive.About 5% of GISTs are truly negative for KIT expression.GISTs have been documented to resistant conventional chemotherapeutics.Due to the KIT activation that occurs in the majority of the cases,KIT inhibition is the primary treatment approach in the adjuvant treatment of metastatic GISTs.Imatinib mesylate is an oral agent that is a selective protein tyrosine kinase inhibitor of the KIT protein tyrosine kinase,and it has demonstrated clinical benefit and objective tumor responses in most GIST patients in phase Ⅱ and Ⅲ trials.The presence and the type of KIT or PDGFRA mutation are predictive of response to imatinib therapy in patients with advanced and metastatic disease.Molecular analysis in phaseⅠ-Ⅱ trials revealed significant differences in objective response,progression-free survival,and overall survival between GISTs with different kinase mutations.The aim of this letter is to touch on the need for exon mutation analysis for adjuvant treatment with imatinib in GIST patients. 展开更多
关键词 IMATINIB Gastrointestinal stromal tumor Activating mutation Stem cell FACTOR RECEPTOR PLATELET-DERIVED growth FACTOR RECEPTOR alpha mutation analysis
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Analysis of the Phenotype and the Restriction Enzyme Mapping Level of Mutations Induced by the New Mutagen Glycidyl Methacrylate 被引量:5
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作者 XIE DA-YING GAO HUI-LAN +4 位作者 ZUO JIN ZHANG WEI LI ZHONG-SHENG YANG HUI-FANG FANG FU-DE 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1990年第2期146-155,共10页
Glycidyl methaerylate (GMA) is a recently recognized chemical mutagen. In order to explore the mutagenicity and mutagenic process of GMA, plasmid pBR322 was used for in vitro binding, mutant screening, and restriction... Glycidyl methaerylate (GMA) is a recently recognized chemical mutagen. In order to explore the mutagenicity and mutagenic process of GMA, plasmid pBR322 was used for in vitro binding, mutant screening, and restriction enzyme mapping. The binding between GMA and DNA in vitro has been verified by means of a spectrophotometric method. When pBR322 and GMAbound pBR322 were used to transform Eschenchia coli HB101, the following results were obtained: (1) The transformation efficiency of GMA-bound pBR322 was much lower than that of pBR322 alone. (2) GMA-bound pBR322 induced phenotype changes in competent cells (i.e., tetracycline-resistance inactivation or ampicillin-resistance inactivation). There were two mutants of pBR322, Ap~RTc~S and Ap~STc~R, in the transformants and a deductive mutant Ap~STc~S in the nontranstormants. (3) All of the selected mutants were stable and heritable. (4) When restriction enzyme maps were used to analyze the mutant Ap~RTc~S, four of seven maps were changed. some sites were shifted to other resistant gene regions, for example, sites of Bgll, EcoRl, Ilindlll. Hinclll, etc., and there was a new recognition site for Hindi (252). We did not observe any DNA fragment insertion or deletion on any maps. Our results suggest that when GMA is covalently linked to the plasmid DNA, it gives rise to a premutagenic lesion of DNA that is converted in vivo into a point mutation. (C)1990 Academic Press, Inc. 展开更多
关键词 analysis of the Phenotype and the Restriction Enzyme Mapping Level of mutations Induced by the New Mutagen Glycidyl Methacrylate
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BRAF^(V600E) Mutation and Its Association with Clinicopathological Features of Papillary Thyroid Microcarcinoma: A Meta-Analysis 被引量:9
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作者 马禹佳 邓秀玲 黎慧清 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2015年第4期591-599,共9页
Summary: Recent studies have demonstrated that the BRAFv600E mutation is associated with aggres- sive clinicopathological features of papillary thyroid carcinoma (PTC). However, the BRAF mutation as a prognostic bi... Summary: Recent studies have demonstrated that the BRAFv600E mutation is associated with aggres- sive clinicopathological features of papillary thyroid carcinoma (PTC). However, the BRAF mutation as a prognostic biomarker in papillary thyroid microcarcinoma (PTMC) is unclear. A systematic search of the electronic databases, including Medline, Scopus, CNKI and the Cochrane Library was performed up to July 1, 2014. Outcomes of interest included age, gender, concomitant hashimoto thyroiditis or nodular goiter, tumor size, pathological stage, tall cell variant of PTMC (TCVPTMC), multifocality, extrathyroidal extension (ETE) and lymph node metastasis (LNM). A total of 19 studies published from 2008 to 2014 comprising 2253 patients fulfilled the inclusion criteria and were in- cluded in the meta-analysis, and 1143 (50.7%) of these patients were BRAF mutation positive. BRAF mutation was associated with larger tumor size (OR: 1.64; 95% CI: 1.16-2.32), multifocality (OR: 1.58; 95% CI: 1.25-2.00), ETE (OR: 2.59; 95% CI: 2.03-3.29), LNM (OR: 1.73; 95% CI: 1.14-2.62), advanced stage (OR: 2.03; 95% CI: 1.14-3.64) and TCVPTMC (OR: 5.07; 95% CI: 1.49-17.27; P=0.009). Additionally, the BRAF mutation was found to be not associated with age, gender, con- comitant hashimoto thyroiditis or nodular goiter (P〉0.05 for all). This meta-analysis revealed that in patients with PTMC, BRAF mutation is associated with tumor size, multifocality, ETE, LNM, ad- vanced stage and TCVPTMC, and it may be used as a predictive factor for prognosis of PTMC. 展开更多
关键词 BRAFV600E mutation papillary thyroid microcarcinoma META-analysis
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Quantitative evaluation of hepatitis B virus mutations and hepatocellular carcinoma risk:a meta-analysis of prospective studies 被引量:8
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作者 Yang Yang Jiang-Wei Sun +2 位作者 Long-Gang Zhao Freddie Bray Yong-Bing Xiang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第5期497-508,共12页
Background: The temporal relationship between hepatitis B virus (HBV) mutations and hepatocellular carcinoma (HCC) remains unclear. Methods: We conducted a meta-analysis including cohort and nested case-control ... Background: The temporal relationship between hepatitis B virus (HBV) mutations and hepatocellular carcinoma (HCC) remains unclear. Methods: We conducted a meta-analysis including cohort and nested case-control studies to prospectively examine the HCC risk associated with common variants of HBV in the PreS, Enhancer Ⅱ, basal core promoter (BCP) and precore regions. Pertinent studies were identified by searching PubMed, Web of Science and the Chinese Biological Medicine databases through to November 2014. Study-specific risk estimates were combined using fixed or random effects models depending on whether significant heterogeneity was detected. Results: Twenty prospective studies were identified, which included 8 cohort and 12 nested case-control studies. There was an increased risk of HCC associated with any PreS mutations with a pooled relative risk (RR) of 3.82 [95% confidence interval (CI): 2.59-5.61]. The pooled-RR for PreS deletion was 3.98 (95% CI: 2.28-6.95), which was higher than that of PreS2 start codon mutation (pooled-RR=2.63, 95% CI: 1.30-5.34). C1653T in Enhancer Ⅱ was significantly associated with HCC risk (pooled-RR=l.83; 95% CI: 1.21-2.76). For mutations in BCP, statistically significant pooled-RRs of HCC were obtained for T1753V (pooled- RR=2.09; 95% CI: 1.49-2.94) and AI762T/G1764A double mutations (pooled-RR=3.11; 95% CI: 2.08- 4.64). No statistically significant association with HCC risk was observed for G1896A in the precore region (pooled-RR=0.77; 95% CI: 0.47-1.26). Conclusions: This study demonstrated that PreS mutations, C1653T, T1753V, and A1762T/G1764A, were associated with an increased risk of HCC. Clinical practices concerning the HCC risk prediction and diagnosis may wish to focus on patients with these mutations. 展开更多
关键词 Hepatitis B virus (HBV) mutation hepatocellular carcinoma (HCC) prospective study META-analysis
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Mutation analysis of 13 driver genes of colorectalcancer-related pathways in Taiwan Residents patients
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作者 Yuli Christine Chang Jan-Gowth Chang +5 位作者 Ta-Chih Liu Chien-Yu Lin Shu-Fen Yang Cheng-Mao Ho William Tzu-Liang Chen Ya-Sian Chang 《World Journal of Gastroenterology》 SCIE CAS 2016年第7期2314-2325,共12页
AIM To investigate the driver gene mutations associatedwith colorectal cancer (CRC) in the Taiwan Residentspopulation.METHODS: In this study, 103 patients with CRCwere evaluated. The samples consisted of 66 menand ... AIM To investigate the driver gene mutations associatedwith colorectal cancer (CRC) in the Taiwan Residentspopulation.METHODS: In this study, 103 patients with CRCwere evaluated. The samples consisted of 66 menand 37 women with a median age of 59 years and anage range of 26-86 years. We used high-resolutionmelting analysis (HRM) and direct DNA sequencing tocharacterize the mutations in 13 driver genes of CRCrelatedpathways. The HRM assays were conductedusing the LightCycler? 480 Instrument provided with the software LightCycler 480 Gene Scanning SoftwareVersion 1.5. We also compared the clinicopathologicaldata of CRC patients with the driver gene mutationstatus.RESULTS: Of the 103 patients evaluated, 73.79%had mutations in one of the 13 driver genes. Wediscovered 18 novel mutations in APC , MLH1 , MSH2 ,PMS2 , SMAD4 and TP53 that have not been previouslyreported. Additionally, we found 16 de novo mutationsin APC , BMPR1A , MLH1 , MSH2 , MSH6 , MUTYH andPMS2 in cancerous tissues previously reported in thedbSNP database; however, these mutations couldnot be detected in peripheral blood cells. The APCmutation correlates with lymph node metastasis(34.69% vs 12.96%, P = 0.009) and cancer stage(34.78% vs 14.04%, P = 0.013). No association wasobserved between other driver gene mutations andclinicopathological features. Furthermore, having twoor more driver gene mutations correlates with thedegree of lymph node metastasis (42.86% vs 24.07%,P = 0.043).CONCLUSION: Our findings confirm the importanceof 13 CRC-related pathway driver genes in the developmentof CRC in Taiwan Residents patients. 展开更多
关键词 COLORECTAL cancer Driver gene Colorectalcancer-related pathway mutation High-resolutionmelting analysis
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Detection of rare mutation of β-thalassemia by direct sequence analysis of the PCR products
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作者 单越新 张基增 徐钤 《Journal of Medical Colleges of PLA(China)》 CAS 1993年第3期235-241,共7页
A technique of direct sequence analysis of β-globin gene with the products of amplifi-cation by polymerase chain reaction (PCR) was reported and a case of β-thalassemia with therare mutation in Chinese,‘codon 14/15... A technique of direct sequence analysis of β-globin gene with the products of amplifi-cation by polymerase chain reaction (PCR) was reported and a case of β-thalassemia with therare mutation in Chinese,‘codon 14/15 (+G)’ was detected by this method.After the se-quence of the mutation site was determined,an analysis of the restriction map of the gene anddot blot hybridization with radioactive allele specific oligonucleotide probe was designed to con-firm the result of DNA sequencing. 展开更多
关键词 POLYMERASE CHAIN reaction(PCR) mutation DNA sequence analysis Β-THALASSEMIA
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Variation Characteristics and Mutation Analysis of the Temperature in Fangchenggang of Guangxi in Recent 55 Years
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作者 XU Wen-long HUANG Chun-hua +2 位作者 GUO Qing-yuan HU Jian-ming CHEN Shao-he 《Meteorological and Environmental Research》 CAS 2012年第12期5-7,12,共4页
[Objective] The research aimed to analyze change characteristics and mutation situation of the temperature in Fangchenggang of Guangxi from 1955 to 2009. [Method] Based on actual temperature observation data in Fangch... [Objective] The research aimed to analyze change characteristics and mutation situation of the temperature in Fangchenggang of Guangxi from 1955 to 2009. [Method] Based on actual temperature observation data in Fangchenggang of Guangxi from 1955 to 2009, by using linear trend estimation, Mann-Kendall and cumulative anomaly, change characteristics and mutation situation of the temperature in the city in recent 55 years were analyzed. [Result] Annual average temperature had an obvious rising trend in Fangchenggang in recent 55 years, which was basically consistent with that in whole country. Summer, autumn and winter average temperatures all had obvious warming trends except that the trend in spring. Summer, winter and annual average temperature jumps occurred in the 1980s. Autumn average temperature jump occurred in the end of 1970s while spring average temperature had no jump. The situation in winter was that a transition from low stage to high stage happened in the middle period of 1980s, while transitions of the annual, spring, summer and autumn average temperatures from low stage to high stage happened in the middle and later periods of 1990s. [Conclusion] The research provided decision-making basis for going after advantages and avoiding disadvantages, guiding agricultural production and using climate resource in the zone sufficiently and reasonably. 展开更多
关键词 Fangchenggang City Temperature variation Characteristic analysis mutation China
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Mutational and Phylogenetic Analysis of <i>nfxB</i>Gene in Multidrug-Resistant Clinical Isolates of <i>Pseudomonas aeruginosa</i>Hyperexpressing MexCD-OprJ Efflux Pump
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作者 Manju Suresh Nithya Narayanan +2 位作者 Kollancheri Puthurath Vimal Pullampara Rajamma Jayasree Panickassery Ramakrishnan Manish Kumar 《Advances in Microbiology》 2019年第12期993-999,共7页
The present study focused on MexCD-OprJ efflux pump and its regulatory gene nfxB in multidrug resistant (MDR) clinical isolates of Pseudomonas aeruginosa collected from Kerala, South India. Semi-quantitative reverse t... The present study focused on MexCD-OprJ efflux pump and its regulatory gene nfxB in multidrug resistant (MDR) clinical isolates of Pseudomonas aeruginosa collected from Kerala, South India. Semi-quantitative reverse transcription-PCR technique was employed to detect hyperexpression of the efflux pump gene, mexD. Amplicons from nfxB gene of isolates hyperexpressing the efflux pump were sequenced for mutational and phylogenetic analysis. Among 29 isolates of MDR P. aeruginosa, increased mexD transcription was detected in 10.3% of the isolates when compared with P. aeruginosa reference strain, PAO (MTCC-3541). Various synonymous and non-synonymous mutations in nfxB regulatory gene sequences were detected. Notably, mutations detected in the strains designate Pa6 and Pa7 have been found to be novel and are hitherto unreported in GenBank data base. The genetic divergence and homogeneity of the nfxB regulatory gene sequences of mexCD-oprJ operon were clearly apparent in the phylogram generated employing similar sequences retrieved from the public database. 展开更多
关键词 MULTIDRUG-RESISTANT Pseudomonas AERUGINOSA EFFLUX Pump Regulatory GENE mutational Variations Phylogenetic analysis
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Epidemiology and Mutational Analysis of Global Strains of Crimean-Congo Haemorrhagic Fever Virus
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作者 Simon Rayner 《Virologica Sinica》 SCIE CAS CSCD 2011年第4期229-244,共16页
Crimean-Congo hemorrhagic fever (CCHF) is a severe illness with high fatality.Cases are reported in several countries in Africa,Europe,the Middle East,and Asia.Phylogenetic analyses based on the virus S (nucleocapsid)... Crimean-Congo hemorrhagic fever (CCHF) is a severe illness with high fatality.Cases are reported in several countries in Africa,Europe,the Middle East,and Asia.Phylogenetic analyses based on the virus S (nucleocapsid),M (glycoprotein),and L (polymerase) genome segments sequences indicate distinct geographic lineages exist but their specific genetic characteristics require elucidation.In this work we collected all full length S segment sequences and generated a phylogenetic tree based on the alignment of these 62 samples.We then analyzed the alignment using entries from AAIndex,the Amino Acid Index database,to identify amino acid mutations that performed significant changes in charge,pka,hydropathy and side chain volume.Finally,we mapped these changes back to the tree and alignment to identify correlated mutations or sites that characterized a specific lineage.Based on this analysis we are able to propose a number of sites that appear to be important for virus function and which would be good candidates for experimental mutational analysis studies. 展开更多
关键词 Crimean-Congo hemorrhagic fever virus (CCHFV) EPIDEMIOLOGY mutational analysis
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P53 GENE MUTATIONS IN NON-SMALL CELL LUNG CANCER DETECTED BY POLYMERASE CHAIN REACTION SINGLE-STRAND CONFORMATION POLYMORPHISM ANALYSIS
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作者 赵永良 吴德昌 +3 位作者 项晓琼 张宝仁 周乃康 胡迎春 《Chinese Medical Sciences Journal》 CAS CSCD 1999年第3期134-137,共4页
Mutations of the p53 tumor suppressor gene are the most frequent genetic alterations detected in human lung cancer. To assess the pathogenic significance of p53 gene alterations in Chinese non small cell lung cancer(... Mutations of the p53 tumor suppressor gene are the most frequent genetic alterations detected in human lung cancer. To assess the pathogenic significance of p53 gene alterations in Chinese non small cell lung cancer(NSCLC),74 paired samples of primary lung cancer and normal lung tissue far away from the cancer were analyzed for mutations of the p53 gene(exons 5 8) using exon specific PCR, single strand conformation polymorphism (PCR SSCP). p53 mutations were observed in 55 4%(41/74) of the samples. No linkages were detected between the incidence of p53 mutations and histological type, lymph node metastasis,age or sex. Significant association between p53 mutations and degree of differentiation in adenocarcinomas, not in squamous cell carcinomas, was observed. The frequency of p53 mutations in smokers(65 3%) was higher than in nonsmokers(33 3%) and reached statistical significance.We also found p53 mutations in 6/7 samples which had tissue invasion and distant metastasis.These results suggest that smoking could be an important factor in lung carcinogenesis,p53 mutation is a worse prognosis indicator in adenocarcinomas and related to high aggressive behavior of human lung cancer. 展开更多
关键词 p53 mutation lung cancer PCR SSCP analysis
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