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1.
Aim: Rheumatoid arthritis (RA) is the most common chronic inflammatory erosive joint disease with the worldwide distribution of approximately 0.5–1.0%. Etiology of RA is not exactly known but immunologic and genetic factors play an important role in the pathogenesis of the disease. Genetic factors such as human leukocyte antigens (HLA) are responsible for many autoimmune diseases; therefore we decided to look for a correlation between RA and the presence of HLA‐DQβ1 alleles as possible genetic markers. Methods: Genomic DNA from the whole blood samples of 25 patients with RA and 86 normal individuals as control group were extracted by salting out method. The genomic DNA was amplified by polymerase chain reaction‐sequence specific primer (PCR‐SSP) technique. HLA‐typing was done by this method after optimizing the PCR reaction for each allele. In this procedure seven serological subclasses of HLA‐DQβ1 can be detected. Results: Comparing the results between the patients and controls show a significant increase in the frequency of HLA‐DQ8 (*0302, *0305) alleles in RA patients. The P‐values were 0.007 and the relative risk for these alleles was evaluated higher than 1. Conclusions: The results suggest that DQ8 is the dominant HLA‐DQβ1 allele that is associated with susceptibility to RA in north‐eastern Iran.  相似文献   
2.
ABO血型基因分型及应用   总被引:11,自引:0,他引:11  
目的 :研究ABO血型基因分型的意义。方法 :采用聚合酶链反应 序列特异性引物 (PCR SSP)基因定型方法对ABO血型基因定型并观察其基因多态性分布特征和疑难血型检定。结果 :对已知ABO基因的DNA标本进行基因定型 ,证实文中的ABO基因定型方法可靠 ;对 10 4例健康、无血源关系的汉族个体ABO血型基因定型 ,结果与血清学所定表型完全符合 ;并用ABO基因分型技术解决临床输血前血型鉴定、产前胎儿血型鉴定、亲权试验及血清学亚型的正确性验证。结论 :ABO血型基因分型技术可以正确判定ABO血型疑难样本  相似文献   
3.
用PCR-SSP对HLA-DQB作中分辨法分型   总被引:6,自引:2,他引:4  
采用PCR-序列特异性引物技术(SSP)对HLA-DQB作中分辨法分型。该方法不仅可行,且操作简便快速,结果准确,适用于临床器官移植配型。  相似文献   
4.
目的研究人类白细胞抗原(HLA)DQA1基因位点上是否存在H.pylori感染的易感基因或抵抗基因,探讨免疫遗传因素在H.pylori感染中的作用。方法用聚合酶链反应-序列特异性引物(PCR-SSP)技术对用血清学试验及^13C尿素呼气实验确诊的31例H.pylori感染的彝族儿童及39例无感染儿童进行HLA.DQA1基因分型。结果感染组HLA-DQA1*0102等位基因频率明显高于对照组(14.52%vs3.85%,P=0.025,Pc=0.35),OR=4.245(95%CI:1.097~16.428);感染组HLA-DQA1*0302等位基因频率低于对照组(0 vs12.82%,P=0.003,Pc=0.042),OR=1.147(95%CI:1.053-1.249)。结论在HLA-DQA1位点上,H.pflori感染的彝族儿童与对照组儿童存在免疫遗传学差异,HLA-DQA1*0102基因可能是彝族H.pylori感染的易感基因,而HLA-DQA1*0302基因则可能是抵抗基因和具有免疫抵抗作用。  相似文献   
5.
小儿支气管哮喘与HLA的相关性研究   总被引:10,自引:0,他引:10  
目的探讨小儿支气管哮喘与HLA-DRB1的相关件。方法采用序列特异性引物.聚合酶链反应方法(PCR/SSP)对78例支气管哮喘患儿和82例健康儿章进行HLA-DRB1基因分析,患儿的年龄为1~14岁,平均6.5岁。HLA-DRB。有19个等位基因,包括DR1-DRw18、DRw52和DRw53。计算各个位点的基因分布频率、危险性比值比OR值;并进行卡方检验,筛选有意义基因。结果支气管哮喘患儿HLA-DRB1^*9的基因频率为10.8%;HLA-DRB1^*10为11.5%;HLA-DRB1^*1为1.92%。以上3个基因型住疾病组与正常组之间进行卡方检验,x^2值分别为4.39、4.44、6.7,与正常对照组比较差异有显著性(P均〈0.05),其余16个位点差异无显著性。观察组与对照组间进行逐个等位基凶比较,计算比值比OR结果HLA-DRB1^*1的OR值为0.25;HLA—DRB1^*9的OR值为2.58;HLA-DRB1^*10的OR值为2.43。结论HLA-DRB1^*9和HLA-DRB1^*10可能是汉族小儿哮喘的易感基因;而HLA-DRB1^*1可能为保护件基因。  相似文献   
6.
目的:观察人类白细胞相关抗原HLA-DR2,DRB1*0301,DQA1*0501基因频率为多发性肌炎/皮肌炎(PM/DM)发病及其临床表现的关系,方法:特异性引物聚合酶链式反应(PCR-SSP)方法分别测定了31例PM/DM患者及50例正常人的HLA-DR2,DRB1*0301及HLA-DAQ1*0501的基因频率,结果:三种基因型在31例肌炎患得中基频率分别为:6.45%,9.68%和77.4  相似文献   
7.
The KIR locus with genes involved in immune processes is among the most polymorphic and structurally diverse human loci. KIR genes encode activating and inhibitory receptors that differ in specificity for HLA class I ligands and signaling potential. These receptors are expressed principally by natural killer (NK) cells and subpopulations of T cells. This study represents the first report of the distribution of KIR genes, KIR genotypes and KIR/HLA pairs in 121 unrelated healthy Croatian individuals. Twenty-three different genotypes were observed in the Croatian population and all 16 KIR genes known to date were found. The most frequent KIR genotype was the AA genotype. All individuals had at least one inhibitory KIR/HLA pair with the majority of individuals with three inhibitory KIR/HLA pairs. The most frequent KIR/HLA pair was the KIR2DL3/C1 group. Our results demonstrated the similarity of the Croatian population’s KIR repertoire with other Caucasian populations reported so far.  相似文献   
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9.
A key challenge in the analytical assessment of therapeutic proteins is the comprehensive characterization of their higher-order structure (HOS). To directly assess HOS, a new type of assay is warranted. The most sensitive and detailed method for characterizing HOS is unquestionably nuclear magnetic resonance (NMR) spectroscopy. NMR spectroscopy provides direct information about the HOS at an atomic level, and with modern NMR spectrometers and improved pulse sequences, this has become feasible even on unlabeled proteins. Hence, NMR spectroscopy could be a very powerful tool for control of HOS following, for example, process changes resulting in structural changes, oxidation, degradation, or chemical modifications. We present a method for characterizing the HOS of therapeutic proteins by monitoring their methyl groups using 2D H, C-correlated NMR. We use a statistical model that compares the NMR spectrum of a given sample to a reference and results in one output value describing how similar the HOS of the samples are. This makes the overall result easy to interpret even for non-NMR experts. We show that the method is applicable to proteins of varying size and complexity (here up to ~30 kDa) and that it is sufficiently sensitive for the detection of small changes in both primary and HOS.  相似文献   
10.
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