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61.
目的探讨噬菌体展示随机肽库技术在结核分枝杆菌培养滤过蛋白10(CFP-10)/早期分泌抗原靶点6(ESAT-6)融合蛋白(CE融合蛋白)模拟抗原表位筛选中的应用。方法以抗CE融合蛋白多克隆抗体为靶分子,对随机噬菌体7肽库进行筛选,经3轮生物淘选后,随机选取18个单噬菌体进行测序分析。采用双抗体夹心和竞争ELISA方法对测序后噬菌体进行阳性克隆及其活性鉴定。采用间接ELISA方法,选取阳性单噬菌体与CE融合蛋白分别对20份活动性肺结核患者和10份有卡介苗接种史健康人的血清标本抗体进行检测。结果经过3轮生物淘选,能与靶分子特异性结合的噬菌体得到了明显富集。18个单噬菌体测序共获得9种序列,其中单噬菌体5、6、18的氨基酸序列均包含Trp-Asp-Ala-Thr(WDAT)保守序列,该序列与ESAT-6第58-61位氨基酸的序列一致。9种序列中各取1个单噬菌体经双抗体夹心和竞争ELISA检测,有7个单噬菌体(1、5、6、10、13、14、18,S/N值依次为9.2、9.7、9.4、8.9、9.6、9.9、9.0)确定为具有免疫活性的阳性克隆。选取含有WDAT保守序列的阳性单噬菌体5与CE融合蛋白分别对2种血清标本抗体进行间接ELISA检测结果显示,单噬菌体5对2种血清标本抗体检测的吸光度值均高于CE融合蛋白(分别为0.931±0.298 vs 0.317±0.157、0.496±0.073 vs 0.118±0.026,均P〈0.05);单噬菌体5对活动性肺结核患者血清标本抗体的检出率(95%,19/20)明显高于CE融合蛋白(60%,12/20),而对有卡介苗接种史健康人血清标本抗体的检出率(9/10)低于CE融合蛋白(10/10)。结论利用噬菌体展示随机肽库技术成功筛选出7个CE融合蛋白的模拟抗原表位,并获得了定位于ESAT-6第58-61位氨基酸序列的CE融合蛋白的1个线性B细胞抗原表位,提高了ELISA检测的敏感性,为进一步研究CE融合蛋白的?  相似文献   
62.
A 4-month-old child with multiple anomalies was determined to have an interstitial deletion of chromosome 15, i.e., del(15) (q12q14). The deletion appears not to be a typical deletion of 15q12 such as seen in Angelman and Prader-Willi syndromes, but appears to be more distal, involving either loss of all of 15q12 and part of 15q14, or part of 15q12 and most of 15q14. In either case, 15q13 is missing. Fluorescent in situ hybridization with probes for 15 centromere (D15Z), pericentromeric satellite sequences (D15Z1), and chromosome 15 painting probes shows the deleted chromosome to involve only 15 and no other acrocentric chromosome. Hybridization with probes for the AS and PWS loci (D15S11 and GABAB3, Oncor) show both sites to be intact in the deleted 15. The case is compared with two other reports with overlapping interstitial deletions of proximal 15q, neither of which shows typical features of Angelman or Prader-Willi syndromes.  相似文献   
63.
64.
Brachydactyly type A (BDA) is defined as short middle phalanges of the affected digits and is subdivided into four types (BDA1‐4). To date, the molecular cause is unknown. However, there is some evidence that pathogenic variants of HOXD13 could be associated with BDA3 and BDA4. Here, we report a Chinese autosomal dominant BDA3 pedigree with a novel HOXD13 mutation. The affected individuals presented with an obviously shorter fifth middle phalanx. The radial side of the middle phalanx was shorter than the ulnar side, and the terminal phalanx of the fifth finger inclined radially and formed classical clinodactyly. Interestingly, the index finger was normal. The initial diagnosis was BDA3. However, the distal third and fourth middle phalanges were also slightly affected, resulting in mild radial clinodactyly. Both feet showed shortening of the middle phalanges, which were fused to the distal phalanges of the second to the fifth toes, as reported in BDA4. Therefore, this pedigree had combined BDA3 and atypical BDA4. By direct sequencing, a 13 bp deletion within exon 1 of HOXD13 (NM_000523.4: c.708_720del13; NP_000514.2: p.Gly237fs) was identified. The 13 bp deletion resulted in a frameshift and premature termination of HOXD13. This study provides further evidences that variants in HOXD13 cause BDA3‐BDA4 phenotypes.  相似文献   
65.

Introduction

MED13L-related intellectual disability is characterized by moderate intellectual disability (ID), speech impairment, and dysmorphic facial features. We present 8 patients with MED13L-related intellectual disability and review the literature for phenotypical and genetic aspects of previously described patients.

Materials and methods

In the search for genetic aberrations in individuals with ID, two of the patients were identified by chromosomal microarray analysis, and five by exome sequencing. One of the individuals, suspected of MED13L-related intellectual disability, based on clinical features, was identified by Sanger sequencing.

Results

All 8 individuals had de novo MED13L aberrations, including two intragenic microdeletions, two frameshift, three nonsense variants, and one missense variant. Phenotypically, they all had intellectual disability, speech and motor delay, and features of the mouth (open mouth appearance, macroglossia, and/or macrostomia). Two individuals were diagnosed with autism, and one had autistic features. One had complex congenital heart defect, and one had persistent foramen ovale. The literature was reviewed with respect to clinical and dysmorphic features, and genetic aberrations.

Conclusions

Even if most clinical features of MED13L-related intellectual disability are rather non-specific, the syndrome may be suspected in some individuals based on the association of developmental delay, speech impairment, bulbous nasal tip, and macroglossia, macrostomia, or open mouth appearance.  相似文献   
66.
Comparative genomic hybridization (CGH) analyses have detected gains of copy number on 13q, especially at 13q31-q32, in cell lines and primary cases of various types of lymphoma. Since amplification of chromosomal DNA is one of the mechanisms that can activate tumor-associated genes, and because 13q amplification had been reported in various other types of tumors as well, we attempted to define by fluorescence in situ hybridization (FISH) a common region at 13q31-q32 in which to explore genes that might be targets for the amplification events. Although the commonly amplified region we defined was relatively large (approximately 4 Mb), only one true gene, GPC5, was found there. GPC5 was over-expressed in lymphoma cell lines that had shown amplification, in comparison with those that had not. Our findings suggest that GPC5 is a likely target for amplification, and that over-expression of this gene may contribute to development and/or progression of lymphomas and other tumors.  相似文献   
67.
68.
Adult Still's disease reflects a Th2 rather than a Th1 cytokine profile   总被引:2,自引:0,他引:2  
Adult Still's disease (ASD) is a chronic multisystemic disease. Extraordinarily high serum levels of IL-18 in ASD patients have been described, whereas the mechanism remains to be clarified. This study aimed to evaluate proinflammatory cytokines and to consider their pathological roles. In patients with rheumatic diseases (n = 151), blood samples were taken at the active phase and the serum levels of IL-18 and other proinflammatory cytokines were measured by ELISA. The extra-high levels of IL-18 were confirmed selectively in ASD patients (n = 10). In the active phase of ASD patients, the levels of IL-6 were elevated accordingly, but IL-1beta and TNF-alpha were undetectable. As to Th1-Th2 cytokines, the levels of IL-4 and IL-13, but not INF-gamma, IL-12, or IL-2, were elevated in all ASD patients examined. Moreover, the serum levels of IL-18 showed a good correlation with those of IL-4, suggesting that ASD reflects a Th2 rather than a Th1 cytokine profile.  相似文献   
69.
目的研究基质金属蛋白酶-9(matrix metalloproteinases,MMP-9)及其组织抑制物-1(tissue inhibitor of metalloproteinases,TIMP-1)在不同孕期胎盘中的表达及与滋养层细胞侵蚀、子宫-胎儿血管系统建立的关系.方法应用原位杂交法检测56例胎盘(早孕16 例、中孕20 例、晚孕20例)中MMP-9及TIMP-1mRNA的表达.结果 MMP-9及TIMP-1mRNA主要表达于滋养细胞、绒毛间质血管壁及蜕膜组织中;MMP-9mRNA的表达早、中孕组明显强于晚孕组,TIMP-1mRNA的表达晚孕组明显强于早、中孕组,差异均有极显著性(P<0.01).结论 MMP-9及TIMP-1协同表达可能在滋养层细胞侵蚀、孕卵着床、血管重建过程中发挥一定的作用.  相似文献   
70.
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