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991.
Minori Saeki Mikio Watanabe Naoya Inoue Ena Tokiyoshi Yukina Takuse Yuya Arakawa 《Autoimmunity》2016,49(8):514-522
Dicer and Drosha are RNase III enzymes that are necessary for the biogenesis of most miRNAs. However, there are no reports on the association of Dicer and Drosha with the pathogenesis of autoimmune thyroid disease (AITD). We genotyped DICER rs3742330A/G and rs1057035T/C as well as DROSHA rs644236C/T and rs10719C/T polymorphisms in 255?Hashimoto's disease (HD) patients, in 255 Graves' disease (GD) patients and in 128 healthy controls by the polymerase chain reaction (PCR)- restriction fragment length polymorphism (RFLP) method. We also examined the expression of DICER and DROSHA gene in peripheral blood mononuclear cells (PBMCs) by quantitative RT-PCR (qRT-PCR) methods. The TT genotype of the DICER rs1057035 polymorphism was less frequent in GD patients (p?=?0.0098) than in healthy subjects. The CC genotype of DROSHA rs644236 polymorphism were more frequent in GD patients than in HD patients (p?=?0.0171). The gene expression of DICER was lower in patients with AITD compared with that in control subjects (p?=?0.0064) and was lower in patients with GD in remission than in patients with intractable GD (p?=?0.0213). In addition, the expression of DROSHA was lower in patients with AITD than that in control subjects (p?0.0001) and was lower in patients with severe HD than in patients with mild HD (p?=?0.0440). In conclusion, the DICER rs1057035 TT genotype and DROSHA rs644236?CC genotype were associated with the development of GD and the differentiation between GD and HD, respectively. The expression levels of DICER and DROSHA genes were low in AITD and differed depending on the intractability of GD and the severity of HD, respectively. 相似文献
992.
993.
Methylmalonic aciduria(MMA) is a common inherited autosomal recessive disorder resulting from defects in the enzyme methylmalonyl CoA mutase(MCM,mut complementation group) or in the synthesis of the MCM cofactor adenosylcobalamin(cbl complementation groups).The defects in the mut complementation group accounts for the largest number of patients with isolated MMA.At least 200 mutations in the MUT gene on chromosome 6p12 have been identified in MMA patients until now.This study aimed to investigate the clinical characteristics of MMA and genomic variations in the MUT gene of Chinese patients.Genomic DNA was extracted from 18 patients who were diagnosed as having isolated MMA by gas chromatography/mass spectrometry(GC-MS),and from some of their parents as well.Amplification and direct sequencing of the MUT coding regions(exon 2-13) and their adjacent intronic consensus splice sites were performed in order to identify the disease causing mutations.In this group,six novel mutations in the MUT gene,c.424A>G(p.T142A),c.786T>G(p.S262R),c.808G>C(p.G270R),c.13231324insA,c.1445-1G>A and c.1676+77A>C were identified.p.T142A and p.G270R were respectively detected at a heterozygous level in one patient.Two previously reported mutations,c.682C>T(p.R228X) and c.323G>A(p.R108H) were also found in this study.In addition,six previously described single nucleotide polymorphism(SNP),c.636A>G(p.K212K),c.1495G>A(p.A499T),c.1595A>G(p.H532R),c.1992G>A(p.A664A),c.2011G>A(p.V671I) and c.1677-53A>G were identified.In this study,we updated the spectrum of MUT mutations and identified the main MMA-causing mutations in Chinese MMA patients. 相似文献
994.
目的探讨中国北方汉族人群代谢型谷氨酸受体3(GRM3)基因多态性与酒依赖的相关性。方法采用聚合酶链反应(Polymerase Chain Reaction,PCR)和连接酶检测反应(Ligase Detection Reaction,LDR)方法,检测100例酒依赖患者和100例正常对照的GRM3基因上3个位点rs1468412、rs917071和rs1989796的基因多态性。结果酒依赖组和对照组之间GRM3基因rs1468412、rs917071以及rs1989796位点的等位基因频率和基因型分布的差异均无统计学意义(P>0.05),但酒依赖组中rs1468412、rs917071和rs19897963个位点所构建的单倍型TTT的频率明显高于对照组(6%vs.1%,OR=5.17,P<0.05),TTT基因型携带者患酒依赖的可能性较高。结论在本样本中,中国北方汉族人群GRM3基因rs1468412、rs917071和rs1989796位点的多态性单独存在时与酒依赖无关联,而由此3个位点所构建的单倍型TTT可能为酒依赖的易感危险因素。 相似文献
995.
目的 了解华山医院泛耐药肺炎克雷伯菌株及其流行的特点.方法 收集2006年8月-2009年12月对CLSI推荐常规检测药物均耐药的肺炎克雷们菌临床分离株,共57株.所有菌株都进行药物敏感试验、超广谱β-内酰胺酶(ESBLs)初筛及表型确证试验、改良Hodge试验、等电聚焦电泳,聚合酶链反应及其产物测序、接合试验、肠杆菌基因间重复共有序列PCR(ERIC-PCR)和多位点序列分型(MLST).结果 所有菌株都携带blaKPC-2、blaCTX-M-14、blaSHV12和blaTEM-1及qnrB和aac(6')-I b-cr基因.57株细菌中ST423型5株,MIST ST11型52株.ST423型散发,而ST11型呈医院内流行.57株细菌都对替加环素耐药,对多黏菌素、米诺环素和多西环素部分敏感.结论 本次泛耐药肺炎克雷们流行主要为ST11型菌株;不同的肺炎克雷伯菌株,播散能力不同;检出泛耐药肺炎克雷伯菌时应增加检测药物的种类. 相似文献
996.
The linear plasmid pMC3-2 from Morchella conica is structurally related to adenoviruses 总被引:4,自引:0,他引:4
Summary pMC3-2, one of two linear plasmids localised in the mitochondria of the ascomycete Morchella conica, was completely sequenced. It is 6044 bp in size, contains terminal inverted repeats of 713 and 710 bp length and two open reading frames, ORF1 and ORF2, spanning 2706 bp and 918 bp, respectively. ORF1 probably encodes a viral B-type DNA-polymerase. Concerning ORF2, no homology to any other published protein-or DNA-sequence could be detected. According to the structure of DNA-polymerases, linear plasmids can be grouped into two classes reflecting their localisation either in the cytoplasm or within the mitochondria. In general, the structure of plasmid pMC3-2, as well as of other linear plasmids from filamentous fungi, indicates a close relationship of these genetic elements to adenoviruses. 相似文献
997.
《European journal of medical genetics》2017,60(12):667-674
We evaluated an approach to detect copy number variants (CNVs) and single nucleotide changes (SNVs), using a clinically focused exome panel complemented with a backbone and SNP probes that allows for genome-wide copy number changes and copy-neutral absence of heterozygosity (AOH) calls; this approach potentially substitutes the use of chromosomal microarray testing and sequencing into a single test. A panel of 16 DNA samples with known alterations ranging from megabase-scale CNVs to single base modifications were used as positive controls for sequencing data analysis. The DNA panel included CNVs (n = 13) of variable sizes (23 Kb to 27 Mb), uniparental disomy (UPD; n = 1), and single point mutations (n = 2). All DNA sequence changes were identified by the current platform, showing that CNVs of at least 23 Kb can be properly detected. The estimated size of genomic imbalances detected by microarrays and next generation sequencing are virtually the same, indicating that the resolution and sensitivity of this approach are at least similar to those provided by DNA microarrays. Accordingly, our data show that the combination of a sequencing platform comprising focused exome and whole genome backbone, with appropriate algorithms, enables a cost-effective and efficient solution for the simultaneous detection of CNVs and SNVs. 相似文献
998.
目的 探讨转化生长因子β1(transforming growth factor beta-1,TGF-β1)基因-509位点多态性与重度慢性牙周炎易感性的关系,以期从基因水平探讨牙周炎发病的遗传学机制.方法 用聚合酶链反应-限制性片段长度多态性方法检测102例重度慢性牙周炎患者(牙周炎组)和102名健康对照者(健康对照组)的TGF-β1基因-509位点,比较两组间此位点基因型分布和等位基因频率的差异.结果 TGF-β1基因-509位点CC、CT、TT基因型在牙周炎组和健康对照组的分布频率分别为44.1%(45/102)、47.1%(48/102)、8.8%(9/102)和29.4%(30/102)、51.0%(52/102)、19.6%(20/102),两组人群基因型分布频率差异有统计学意义(P<0.05);等位基因C、T在牙周炎组和健康对照组分布频率分别为67.6%(138/204)、32.4%(66/204)和54.9%(112/204)、45.1%(92/204),两组人群的等位基因分布频率差异亦有统计学意义(P<0.05),C等位基因携带者患重度慢性牙周炎的风险是T等位基因的1.718倍(OR=1.718,95%CI:1.148~2.569).结论 TGF-β1基因-509位点多态性与重度慢性牙周炎的发病具有相关性,C等位基因可能是重度慢性牙周炎的遗传易感基因. 相似文献
999.
目的研究肝肾移植患者细胞色素P450(cytochrome P450,CYP)3A5和多耐药(multidrugresistance 1,MDR1)基因多态性与他克莫司浓度/剂量比(C/D值)的关系,探讨指导临床个体化用药的可行性。方法采用酶扩大免疫法测定60例肝肾移植患者他克莫司稳态谷浓度,以单位体质量服药日剂量校正血药浓度为浓度/剂量比(C/D值);采用实时荧光定量聚合酶链式反应(RT-PCR)法检测患者CYP3A5A6986G和MDR1C3435T、G2677T/A及T1236C的单核苷酸多态性(SNPs),比较不同基因型患者之间他克莫司C/D值。结果携带CYP3A5*1/*1型者5例,*1/*3 22例,*3/*3 33例,凡携带有*1等位基因者的C/D值(130.40±53.94)明显低于*3/*3型患者的C/D值(198.12±90.80,P<0.01)。MDR1基因C3435T位点C/C型22例,C/T型23例,T/T型15例;T1236C位点T/T型8例,T/C型32例,C/C型20例;G2677T/A位点G/G型9例,G/T型24例,G/A型5例,T/A型8例,T/T型14例,A/A型0例。MDR1的T1236C、G2677T/A和C3435T各基因型的他克莫司C/D值未发现明显差异。结论 CYP3A5A6986G基因多态性可以作为他克莫司个体化用药的依据,CYP3A5*3*3携带者较携带有一条CYP3A5*1等位基因的患者可减少他克莫司的给药剂量。MDR1的T1236C、G2677T/A和C3435T基因多态性与他克莫司血药浓度之间的关系尚需扩大样本量进一步研究。 相似文献
1000.
Victoria Yu Garbuzova Veronika L Gurianova Dmitriy A Stroy Victor E Dosenko Alexander N Parkhomenko Alexander V Ataman 《Experimental & Clinical Cardiology》2012,17(1):30-33