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41.
RSV is one of the major causes of pneumonia and bronchiolitis in infants and young children and is associated with high mortality. RSV neutralizing human antibody (hu-Ab) is known to mediate resistance to viral infection as well as to be an effective treatment for severe lower respiratory tract RSV infection. We have previously demonstrated that human primary and secondary immune responses can be established in severe combined immunodeficient mice engrafted with human peripheral blood lymphocytes (hu-PBL-SCID). By combining this animal model with the single-chain Fv antibody (scFv) phage display library technique, we were able to investigate further its clinical potential by generating a panel of human scFvs that exhibit both high F glycoprotein (RSV-F) binding affinities ( approximately 108 M(-1)) and strong neutralizing activities against RSV infection in vitro. Sequencing analysis of the randomly isolated anti-RSV-F scFv clones revealed that they were derived from different VH families with mutations in the complementarity-determining region 1 (CDR1). The results suggest that: (i) RSV-F-specific human immune responses and affinity maturation can be induced in hu-PBL-SCID mice; and (ii) this approach can be applied to generate large numbers of human scFvs with therapeutic potential. Despite the fact that hu-PBL-SCID mouse and human scFv phage display library have individually been established, our approach contributes a simple and significant step toward the generalization of antigen-specific human monoclonal antibody (hu-MoAb) production and their clinical applications.  相似文献   
42.
研究新鲜人羊膜的变应原性及其致敏后发生I型超敏反应的可能性。建立豚鼠全身主动过敏实验模型。分新鲜羊膜组、新鲜蛋清组(阳性对照)和PBS液组(阴性对照),每组10只豚鼠。观察豚鼠在致敏期和激发后的反应,采用化学荧光法检测外周血组胺含量,血液流变分析系统检测4项血液流变学指标(全血高切变率黏度、全血低切变率黏度、血浆黏度、红细胞聚集指数)。致敏期间各组豚鼠的体重变化无明显差别(P>0.05);激发后羊膜组豚鼠与阴性组表现一致,无异常反应;羊膜组外周血组胺含量及4项血液流变学指标均与阴性对照无明显差别(P>0.05),与阳性对照有显著性差异(P<0.01)。经规范化无菌处理后的新鲜羊膜,一般不具有变应原性,不会引起I型超敏反应。  相似文献   
43.
新生儿血清瘦素水平变化与胰岛素和生长激素关系的研究   总被引:2,自引:0,他引:2  
目的 探讨新生儿血清瘦素来源及其与胰岛素和生长激素的关系。方法 采用放射免疫法检测 80例新生儿静脉血和脐血瘦素水平 ,根据不同胎龄新生儿出生体重值分为大于胎龄儿 (LGA)组 2 8例 ,适于胎龄儿 (AGA)组 36例 ,小于胎龄儿 (SGA)组 16例 ;采用Rohrer′s指数 =出生体重 (g)× 10 0 /身长 (cm) 3 估测新生儿营养状态。结果 早产儿血清瘦素水平明显低于足月儿 (0 6 6± 1 0 3ng/mlvs 3 5 9± 2 16ng/ml,P <0 0 1) ;AGA儿血清瘦素水平 (3 0 6± 0 96ng/m1)明显低于LGA儿(4 0 3± 2 2 2ng/m1) ,而高于SGA儿 (1 13± 1 98ng/m1) ;足月新生儿血清瘦素水平与Rohrer′s指数、新生儿体重、胎龄 ,血清胰岛素、生长激素水平呈显著正相关。结论 新生儿体内瘦素主要来源于自身脂肪组织 ,它反映新生儿的生长营养状态 ,推测瘦素可能通过胰岛素、生长激素共同调节新生儿的生长发育 ,在胎儿和新生儿生长发育中起重要作用。  相似文献   
44.
刺激颈部交感神经节对椎动脉血流影响的实验研究   总被引:13,自引:0,他引:13  
目的 :探讨颈部交感神经因素在造成椎 -基底动脉系统缺血过程中的作用。方法 :健康家兔3 0只 ,手术暴露颈部交感神经节及基底动脉 ,不同方式刺激颈部交感神经节 ,记录、分析基底动脉血流的变化。结果 :刺激前测得基底动脉基线血流为 (5 48± 2 7)PU :分别刺激颈上、中、下交感神经节后测得基底动脉血流为 (5 2 9± 16)PU、(4 74± 16)PU和 (3 70± 3 6)PU。与基线血流相比分别下降了 3 .4%、13 .5 %和 3 2 .5 %。颈部交感神经节阻滞并不能使正常状态下的基底动脉血流增加 ,但可以阻断交感神经缩血管作用。结论 :颈部交感神经受到刺激 ,可造成椎 -基底动脉系统供血不足。  相似文献   
45.
Polydactyly and syndactyly are digital abnormalities in limb‐associated birth defects usually caused by genetic disorders. In this study, a five‐generation Chinese pedigree was found with triphalangeal thumb polysyndactyly syndrome (TPTPS), showing an autosomal dominant pattern of inheritance. We utilized linkage analysis and whole genome sequencing (WGS) for the genetic diagnosis of this pedigree. Linkage analysis was performed using a genome‐wide single nucleotide polymorphism (SNP) chip and three genomic regions were identified in chromosomes 2, 6, and 7 with significant linkage signals. WGS discovered a copy number variation (CNV) mutation caused by a large duplication region at the tail of chromosome 7 located in exons 1–5 of the LMBR1 gene, including the zone of polarizing activity regulatory sequence (ZRS), with a length of approximately 180 kb. A real‐time polymerase chain reaction (PCR) assay confirmed the duplication. The findings of our study supported the notion that large duplications including the ZRS caused TPTPS. Our study showed that linkage analysis in combination with WGS could successfully identify the disease locus and causative mutation in TPTPS, which could help elucidate the molecular mechanisms and genotype–phenotype correlations in polydactyly.  相似文献   
46.
Amplification of the partial Cpn60 (or GroEL) gene segment has been used for identification of many bacteria, including Enterococcus species. To obtain more sequence data from groESL genes of Enterococcus faecalis, the full-length sequence of the E. faecalis groESL genes containing groES (285 bp), spacer (57 bp), and groEL (1,626 bp) was determined. A database search of GenBank revealed that the deduced E. faecalis GroES and GroEL proteins show significant homology to the GroES and GroEL proteins of other bacteria. The GroEL (groEL) of E. faecalis had the highest identity with Streptococcus pneumoniae (81.8% amino acid sequence identity and 73.0% nucleotide sequence identity), followed by Lactococcus zeae, while GroES (groES) had 60.2% (64.6%) identity with Lactobacillus zeae and 58.5% (66.2%) identity with Lactococcus lactis, followed by 57.0% (65.5%) identity with Bacillus subtilis. Based on the groES sequence, an E. faecalis-specific PCR assay was developed, and this PCR assay was positive for all the E. faecalis strains tested. Dot blot hybridization using either groES or groEL as the probe distinguished E. faecalis clearly from other species, indicating that both genes can be used as suitable targets for E. faecalis identification. Moreover, broad-range PCR-restriction fragment length polymorphism of groESL was designed to differentiate eight commonly encountered Enterococcus species. The Enterococcus species of reference strains could be easily differentiated on the basis of restriction patterns produced by HaeIII and RsaI. The DNA-based assays developed in this study provide an alternative to currently used methods of identification for clinically important enterococcal species.  相似文献   
47.
Cell culture-based transdominant genetic techniques provide new methods for discovering peptide/RNA modulators of cellular pathways. We applied this technology to isolate a peptide inhibitor of human rhinovirus. A green fluorescent protein (GFP)-scaffolded library of cDNA fragments was expressed in HeLa cells from a retroviral vector and screened for inhibitors of rhinovirus-mediated cell killing. A DNA clone, I421, increased cell survival in an HRV14 challenge assay from less than 0.5% to greater than 60%. It encodes a 53-amino-acid C-terminal extension of the GFP scaffold. Particular subclones of Hela cells expressing I421 (exemplified by I421dp3) show a delay in virus production and a 50-fold decrease in viral RNA levels at 6-8 h postinfection. HRV2, HRV14, and HRV16 show a dramatic decrease in plaque-forming ability on I421dp3 while Coxsackievirus B3 showed a small reduction. Levels of ICAM-1, the receptor for the main rhinovirus serotype, are not altered in I421dp3.  相似文献   
48.
介绍了一种新型生物组织微阵列芯片自动制备仪的研制。分析了组织微阵列制备过程中的操作任务和实现目标,进行了制备仪的结构设计和各功能模块研究开发。制备仪从结构上分为蜡块承载定位模块和三工位操作模块,控制系统的组成有操作空间精密定位子系统,组织蜡块图像识别子系统,蜡块打孔填埋作业子系统等。研制成功的制备仪样机具备了图像自动识别、精密定位、自动打孔填埋等功能,实现了生物组织微阵列芯片的自动化制备。  相似文献   
49.
罗格列酮对2型糖尿病心肌能量底物代谢的影响   总被引:2,自引:4,他引:2       下载免费PDF全文
目的:探讨在2型糖尿病中胰岛素抵抗(IR)对心肌能量底物代谢以及心功能的影响。 方法: 采用高脂喂养(40%脂肪、42%碳水化合物和18%蛋白)4周及链脲佐菌素(STZ,35 mg/kg)1次性腹腔注射建立2型糖尿病大鼠模型,成模后随机分为2组:实验对照组(fat-fed/STZ)继续高脂喂养,实验治疗组(fat-fed/STZ/RSG)给予罗格列酮(RSG) 3 mg·kg-1·d-1治疗2周;正常对照组(chow-fed)为普通饮食喂养(12%脂肪、60%碳水化合物和28%蛋白)。左室插管检测心功能后进行30 min等容离体心脏灌注,灌注液含100 μU胰岛素、3%BSA、5 mmol/L葡萄糖、0.4 mmol/L[3H]软脂酸,测定样品葡萄糖摄取量及[3H2O]计数,评估葡萄糖和脂肪酸氧化率。 结果: 高脂喂养加小剂量STZ所制备模型鼠的血糖、血浆胰岛素及FFA水平均高于正常鼠,与临床2型糖尿病的代谢特征相似。成模2周后,fat-fed/STZ组大鼠与chow-fed组比较,30 min心肌葡萄糖总氧化量明显减少[(54.7±6.2 vs 69.0±5.7)μmol/g干重,P<0.01]。葡萄糖氧化率由25%降至18%,脂肪酸氧化率由75%增加到82%;同时,心功能检查显示左室EDP明显增加[(14.3±1.8 vs 10.5±1.1) mmHg,P<0.05],-dp/dtmax降低[(550±57 vs 650±42) mmHg/s,P<0.01],而+dp/dtmax无明显改变。与fat-fed/STZ组比较,fat-fed/STZ/RSG组大鼠的血糖明显改善[(9.0±4.6 vs 15.1±3.3) mmol/L,P<0.01],血浆胰岛素减少(P<0.05),FFA降低[(2.2±0.8 vs 3.3±0.8) mmol/L, P<0.05];心肌葡萄糖的总氧化量升高到(63.5±6.4)μmol/g。干重,葡萄糖和脂肪酸的氧化率分别为24%和76%,基本达到chow-fed组水平(P>0.05);EDP和-dp/dtmax均得到明显的改善(P<0.05)。 结论: IR导致2型糖尿病心肌能量底物代谢的异常和左室舒张功能的降低,早期使用RSG改善IR,不仅能提高心肌对葡萄糖的利用、降低脂肪酸氧化,也有助于改善心功能。  相似文献   
50.
Platelet-vessel wall interaction is an important process in physiological hemostasis and pathological thrombosis. In oriental countries, some medicinal plants have been claimed for uses to improve circulation, induce fibrinolysis or prevent thrombosis. In cooperation with chemists using bioassay-based step-by-step purification, some antiplatelet agents were isolated from plant sources. According to their effects on platelet aggregation, release reaction and signal transductions involved, these antiplatelet agents can be classified into eight groups: 1. platelet-activating factor (PAF) antagonists, 2. collagen-receptor antagonists, 3. thromboxane-receptor antagonists, 4. ADP-receptor agonists, 5. inhibitors of phosphoinositide breakdown, 6. inhibitors of thromboxane formation, 7. agents increasing cyclic nucleotides, and 8. protein kinase C activators. These new pharmacological agents derived from medicinal plant sources may be useful as leads to develop as effective cardiovascular drugs.  相似文献   
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