胎盘生长因子串联scFv质粒构建表达及亲和力测定

目的:构建并表达胎盘生长因子串联scFv,提升对胎盘生长因子的亲和力。方法:设计不同长度的柔性连接子连接的串联scFv,构建串联scFv质粒,并分别将串联scFv与亲本scFv于原核表达系统进行表达。通过间接ELISA分别测定串联scFv及对应亲本scFv亲和力,分别对数据进行单因素ANOVA方差分析,并使用Dunnett-t检验进行组间比较。结果:柔性连接子长度的不同,会对串联scFv亲和力造成差别。单因素ANOVA方差分析结果表明,各组亲和常数间存在明显的统计学差异,Dunnett-t检验组间比较结果可知,当串联scFv间柔性连接子（GGGGS）n长度n=4和n=5时,亲和力较亲本提升不明显（P＞0.05）;但亲和力在n=6（t335=33.90,t7A10=32.00,均P<0.000 1）及n=7（t335=91.68,t7A10=90.71,均P<0.000 1）时较两亲本均有明显提升。结论:串联scFv可以明显提高单体scFv亲和力。     

外泌体微RNA治疗骨关节炎研究进展

骨关节炎是骨科常见的顽固性疾病之一,因其高发病率、高致残率,给患者和社会带来沉重的负担。随着组织工程领域的飞速发展,外泌体治疗骨关节炎的潜力已得到证实。其中,外泌体特异性微RNA（miRNA）可抑制软骨降解和滑膜炎症、促进软骨下骨重塑,从而缓解甚至逆转骨关节炎的病理改变。本文对外泌体miRNA治疗对骨关节炎患者软骨、滑膜、软骨细胞外基质及软骨下骨的影响进行综述,以期为临床上应用外泌体miRNA治疗骨关节炎提供参考。     

胃癌术前淋巴结转移评估方法研究进展

胃癌在我国的发病率及病死率较高,目前,手术仍然是胃癌的主要治疗方式。术前诊断淋巴结转移对于胃癌手术方式的选择有着重大意义。目前,临床中对于胃癌术前淋巴结转移的诊断尚没有金标准。本文对胃癌术前淋巴结转移评估方法的研究进展进行综述。     

基因诊断技术在脊柱结核诊断中的应用现状

脊柱结核是一种常见的肺外结核病。近年来,随着脊柱结核患者逐年增多,不典型脊柱结核患者亦逐渐增多,而不典型脊柱结核诊断较为困难,需要与一般细菌感染、肿瘤以及非结核分枝杆菌感染相鉴别。基因诊断技术是一项诊断脊柱结核的重要工具,对临床不典型脊柱结核的诊断有较高价值。本文将对脊柱结核的流行现状、诊断及基因诊断技术进行综述,以帮助临床工作者对脊柱结核做出更加准确的诊断。     

银离子、铜离子和锌离子对常见念珠菌的抗菌性能比较

目的 探讨银离子(Ag⁺)、铜离子(Cu²⁺)、锌离子(Zn²⁺)对5种常见念珠菌(白色念珠菌、热带念珠菌、近平滑念珠菌、克柔念珠菌和光滑念珠菌)的抗菌作用。方法 使用去离子水分别将硝酸银、氯化铜和氯化锌配制为0.1 mol·L^-1的水溶液。取保存的白色念珠菌标准菌株ATCC-60193、近平滑念珠菌、光滑念珠菌、热带念珠菌、克柔念珠菌,加入溶菌肉汤培养液,使用比浊仪调配菌液浊度为0.5麦氏单位,然后使用无菌去离子水将菌液稀释至10⁶ CFU·L^-1。取配制好的0.1 mol·L^-1的硝酸银、氯化铜和氯化锌溶液,分别倍比稀释为6个浓度(10^-2、10^-3、10^-4、10^-5、10^-6、10^-7 mol·L^-1),分别取各浓度的金属离子溶液100μL与预制好的5种念珠菌悬液100μL进...     

Triptolide inhibits IL-12 production and T cell-stimulatory capacity of dendritic cells

Extracts of Tripterygium wilfordii Hook F.(TWHF ) are effective in traditional Chinesemedicine for treatment of autoimmune diseasessuch as rheumatoid arthritis, systemic lupus ery thematosus, nephritis and asthma [1, 2]. Trip tolide, a diterpenoid triepoxide, is derived fromTWHF and is responsible for most of the immuno suppressive and anti inflammatory effects ofTWHF. Triptolide has been shown to be effectivein the treatment of autoimmune diseases, …     

The Distribution of Synaptotagmin II in RBL-2H3 and Its Regulation on Exocytosis of Lysosomes in RBL-2H3

Synaptotagmin(Syt)constitutes a family of membrane-trafficking proteins,so far nearly 20 Syts have beendiscovered.Extensive work showed that synatotagmins were a potential Ca~(2+) sensor for regulated exocytosis.Thisstudy was to investigate the expression and location of synaptotagmin Ⅱ(Syt2)in RBL-2H3(RBL)and its role inregulating exocytosis of RBL.The expression of Syt2 in RBL was confirmed by Western blot.The recombinantexpression vector pEGFP-N1-Syt2 was constructed and transfected into RBL by electroporation,the stabletransfectant RBL-Syt2-S expressing fusion protein Syt2-EGFP were obtained and Syt2 was highly concentrated atplasma membrane with little detected in cytoplasm.To analyze the role of Syt2 during exocytosis of RBL,therelease of cathepsin D was assayed by immunoblotting.Compared with control,the release of cathepsin D byRBL-Syt2-S was markedly decreased.The results indicated that Syt2 played a negative regulation in exocytosis oflysosomes in RBL.Cellular & Molecular Immunology.2005;2(3):205-209.     

Plasma HIV-1 RNA decline within the first two weeks of treatment is comparable for nevirapine, efavirenz, or both drugs combined and is not predictive of long-term virologic efficacy: A 2NN substudy

BACKGROUND: The initial rate of plasma HIV-1 RNA (pVL) decline has been proposed as a marker of early efficacy of antiretroviral therapy (ART) and a possible predictor of late efficacy. We compared the rate of pVL decline in patients starting ART with nevirapine (NVP), efavirenz (EFV), or both drugs combined in addition to lamivudine (3TC) and stavudine (d4T). METHODS: Analysis of the viral decay constant (VDc) during the first 2 weeks of treatment in patients enrolled in the 2NN study who remained on allocated treatment. RESULTS: The median VDc (log10 copies per day, [interquartile range]) was similar for NVP (0.30 [0.25-0.36], EFV (0.31 [0.27-0.37]), and NVP + EFV (0.30 [0.27-0.36]). Patients with a baseline pVL >100,000 copies/mL were 8.7 (95% confidence interval [CI]: 6.2-12.3) times more likely to have a VDc >75th percentile. A high VDc was not associated with plasma drug concentration or with a decreased risk of virologic failure at week 48 after the start of therapy (hazard ratio = 0.8, 95% CI: 0.6-1.2). CONCLUSION: NVP, EFV, or NVP + EFV in combination with 3TC and d4T show similar rates of pVL decline during the first 2 weeks of treatment. The VDc with these regimens is not predictive of late virologic efficacy.     

Human neutrophils secrete gelatinase B in vitro and in vivo in response to endotoxin and proinflammatory mediators

Bacterial sepsis is characterized by a systemic inflammatory state, with activation of numerous cell types. Phagocytes participate in this phenomenon by secreting various proinflammatory cytokines and enzymes. Matrix metalloproteinases (MMPs) such as gelatinases are produced by phagocytes and are thought to play an important role in processes of cell transmigration and tissue remodeling. In this work, we show that endotoxin (lipopolysaccharide [LPS]) and other inflammatory mediators, such as tumor necrosis factor (TNF), interleukin-8, and granulocyte colony-stimulating factor, induce a rapid (within 20 min) release of gelatinase-B (MMP-9) zymogen in whole human blood, as determined by gelatin zymography. The polymorphonuclear neutrophil was identified as the cell responsible for this rapid secretion, as a result of the release of preformed enzymes stored in granules. Normal human subjects given LPS intravenously showed a similar pattern of proMMP-9 secretion, with maximum plasma levels reached 1.5 to 3 h after LPS administration (P = 0.0009). Prior administration of TNF receptor:Fc, a potent TNF antagonist, to subjects given LPS, only partially blunted the release of proMMP-9 (P = 0.033). Ibuprofen, a cyclooxygenase inhibitor, did not alter this pattern of release. Increased levels of proMMP-9 and proMMP-2, as well as activated forms of MMP-9, were found in plasma from two patients with gram-negative sepsis. The levels of MMPs paralleled the severity of clinical condition and a marker of the severity of sepsis, plasma procalcitonin. These data indicate that MMPs are released in whole blood in response to various inflammatory mediators and that they could serve as sensitive and early markers for cell activation during the course of bacterial sepsis.     

The Effects of Extracellular Matrix on Tissue Engineering Construction of Cartilage in Vitro

In the study of bone and cartilage diseases in our laboratory, chondrocyte stereo-differentiation mod-el was cultured into cartilage tissue. The cultured cartilage tissue was closely similar to natural tissue inboth histological condition and biochemical metabolism. The model mimicked the chondrocyte differenti-ation and metabolism in vivo completely〔1〕. We studied some essential extracellular matrices, includingcollagen, proteoglycan(PG) and hyaluronic acid(HA) on the construction of grow…