A preliminary study of expression of human neonatal Fc-receptor (FcRn) in Escherichia coli

IntroductionHuman neonatal Fc-receptor is a potential novel antibody binding protein for development of immunoassay. Previous studies had shown that this human protein has high affinity to Ig G either in vivo or in vitro. However, none of the studies had attempted exploring the utility of human FcRn in antibody immobilisation strategy. In this study, we are in the direction towards development of a novel antibody binding protein by using human FcRn as an immobilisation platform. The three-dimensional structure of the protein was analysed. This protein was successful expressed in bacteria E. coli BL21 (DE3) by using expression vector pET-28b. The pET-28b vector contains poly-histidine tagged which allows detection and purification of expressed proteins.Objectives(1) To study the three dimensional structure of human FcRn, (2) To clone the human FcRn into pET-28b expression vector, (3) To express human FcRn in bacteria E. coli BL21 (DE3).MethodsHuman FcRn cDNA was ligated into pET-28b vector through EcoRI restriction site. The successful clone was transformed into E. coli BL21 (DE3) for expression. Expression in bacteria was induced by IPTG. Induction was conducted under 30°C and 37°C. Expression products were analysed by performing SDS-Page and Western Blot. The 3D structure of human FcRn was studied by using ViewerLite program.Results & DiscussionHuman FcRN was expressed under two sets of temperature, 30°C and 37°C, in 1 hour, 2 hours, 3 hours, and 6 hours. The induction for 3 hours showed highest amount of expressed products, under the above mentioned temperature. The amount of protein expressed in 6 hours of induction showed almost same thickness of band in SDS-PAGE compare to the induction under 3 hours period.ConclusionExpression of human FcRn can be conducted using bacteria expression system, instead of mammalian cell expression system which requires longer time and complicated process. Further study will be conducted to determine the antibody-binding activity and stability of the expressed protein.     

迈瑞公司labXpert系统在血细胞分析自动审核中的应用

 目的 探讨迈瑞公司labXpert系统在血细胞分析自动审核中的应用。方法 选择2017年6－7月采用迈瑞公司labXpert(专家系统)软件审核的血常规数据进行分析。主要包括:(1)统计总体自动审核比例;(2)对违反复检规则的样本进行分析,分析违反规则的样本构成;(3)随机分析800例血常规样本周转时间(TAT)平均值、中位数,并将自动审核与传统审核方式进行对比;(4)统计TAT超过30 min的比例,并将该群样本构成进行分析。结果 共统计10 860例血常规标本,自动审核通过率为84.2%;违反复检规则主要样本类型为:未成熟粒细胞报警提示及数目、WBC超范围(WBC<4.0×10⁹/L或>30×10⁹/L)及反应性淋巴细胞报警提示等相关规则。自动审核TAT中位数为20 min, TAT超过30 min比例为20.63%;传统审核TAT中位数为26 min, TAT超过30 min比例为30.25%;自动审核与传统审核比较,差异有统计学意义(P<0.05)。TAT超时的样本中,WBC系异常最多(P<0.05),其次为RBC系异常及PLT系异常。结论 采用专家系统软件对标本进行自动审核,在保证报告质量同时可以提高工作效率,缩短TAT时间,实验室可以采用该软件对异常构成进行分析,有针对性地优化血常规分析流程。     

雷洛昔酚对大鼠垂体的作用

目的 观察雷洛昔酚是否能诱发出催乳素瘤的动物模型以及对PRL水平的影响,以研究雷洛昔酚对大鼠垂体的作用。方法雌性Wistar大鼠切除卵巢后,分别在皮下埋植含有雷洛昔酚、雌激素和空白硅胶管,术后8周处死大鼠,检测大鼠体重变化、垂体重量变化、血清催乳素(PRL)水平和垂体组织学变化。结果雷洛昔酚组与阴性对照组大鼠体重无明显统计学差异,与雌激素组大鼠体重具有统计学差异(P<0.05)；雷洛昔酚组与阴性对照组大鼠垂体重相比无明显差异,与雌激素组大鼠垂体重相比具有统计学差异(P<0.05)；雌激素组大鼠血清PRL水平最高,阴性对照组血清PRL水平最低,雷洛昔酚组介于两者之间,分别与雌激素组、对照组相比较差异均具有统计学意义(P<0.05)；雷洛昔酚组与对照组垂体病理为正常细胞形态,雌激素组垂体病理为PRL瘤表现。结论雷洛昔酚对大鼠垂体有一定的影响,但不能诱发催乳素瘤。     

精神疾病患者的体内25-(OH)维生素D的不足与缺乏

目的:了解精神疾病患者体内25-(OH)维生素D不足与缺乏的患病率,为合理的维生素D治疗提供依据。方法:用化学发光免疫法定量测定精神分裂症、血管性痴呆和脑器质性疾病伴精神障碍三类人群及健康体检者血清中的25-(OH)维生素D的含量,比较其均值。结果:与对照组相比,三组病人血清中25-(OH)维生素D的含量均低,但精神分裂组和血管性痴呆组偏低程度有显著性差异。结论:维生素D在精神疾病人群中含量较正常人低,提示给予合适的维生素D治疗,可能能促进病情的好转。     

Potential role of ATP-binding cassette transporters in the intestinal transport of rhein

Rhein, a lipophilic anthraquinone, exhibits anti-inflammatory and anti-tumor activities; however, it is hepatotoxic. ATP-binding cassette transporters, including P-glycoprotein (P-gp), breast cancer resistance protein (BCRP) and multidrug resistance-associated protein 2 (MRP2), can pump toxicants from gut epithelial cells back into the intestinal lumen to prevent poisoning. We investigated their roles in rhein transport using a rat intestinal perfusion model and Caco-2, MDCKII-MDR1 (high expression of P-gp), MDCKII-BCRP (high expression of BCRP) and MDCKII-MRP2 (high expression of MRP2) cell models. The permeability of rhein in the duodenum significantly increased with increasing perfused concentration of rhein in the rat model, suggesting that efflux transporters were involved in rhein transport. In the Caco-2 cells, the permeability of rhein from the basolateral (B) to the apical (A) was significantly higher than that from A to B. In the presence of BCRP or MRP2 inhibitor, the permeability of rhein significantly decreased from B to A direction. In the MDCKII-BCRP cells, rhein was more permeable in B to A side than that in the opposite side. However, no significant differences of rhein permeability were observed in two directions in both MDCKII-MDR1 and MDCKII-MRP2 cells. Taken together, these results suggested that only BCRP was involved in rhein transport.     

混合型生物人工肝治疗设备的研制

目的:结合临床应用需求,研制一种新式混合型生物人工肝治疗应用系统。方法:以2个可编程控制器(PLC)作为控制系统核心,辅以多种安全监测报警装置,具有密闭、洁净和恒温的生物反应治疗环境,为离线混合型生物人工肝治疗提供一体化集成解决方案。结果:该设备能实现对血液流量、流速、质量等参数的精确控制,并提供温度、气泡、漏血等参数的报警监测功能。控制系统操作简便,人机界面友好,并为封闭式生物反应离线治疗过程提供实时影像监控。结论:新型治疗设备实现了混合式生物反应人工肝的离线治疗,有效缩短了生物人工肝治疗时间,同时改善了生物治疗环境。     

The downregulation of ANGPTL4 inhibits the migration and proliferation of tongue squamous cell carcinoma

ObjectiveTongue squamous cell carcinoma (TSCC) is the most common malignant cancer in the oral cavity, with a high rate of metastasis to the neck lymphoid node. Angiopoietin-like protein 4 (ANGPTL4) and microvessel density (MVD) may be novel indicators for tumor metastasis. The aim of the present study was to investigate the expression and function of ANGPTL4 in TSCC and the relationship between ANGPTL4 and MVD.MethodsThe expression levels of ANGPTL4 and MVD (CD34) were analyzed in 65 TSCC specimens and the adjacent non-cancerous tissues using immunohistochemistry (IHC). siRNA was delivered into TSCCA cells to downregulate ANGPTL4 expression. Subsequently, validation with real-time RT-PCR and western blot analyses was performed to analyze ANGPTL4 expression levels. In addition, a proliferation assay, migration and invasion assays were carried out.ResultsANGPTL4 expression was associated with tumor stage, lymph node metastasis and MVD expression. Cox regression analysis showed that high levels of ANGPTL4 expression were closely associated with poor survival time. In vitro analyses using qRT-PCR and western blot confirmed that ANGPTL4 was successfully inhibited in TSCCA cells. Suppressing ANGPTL4 resulted in the inhibition of cell proliferation and migration, but neither invasion nor cisplatin resistance was significantly affected.ConclusionHigh expression levels of ANGPTL4 are associated with the T stage, lymphatic metastasis, angiogenesis and poor overall survival in TSCC patients. The downregulation of ANGPTL4 inhibits the migration and proliferation of cells in TSCC. Taken together, ANGPTL4 may serve as a novel biomarker and therapeutic target for TSCC.     

酒精性肝纤维化基质降解机制的研究

目的：揭示酒精性肝病肝纤维化基质降解的病原机制。方法：28例酒精性肝炎肝穿刺组织按其纤维化程度分为3组，利用原位杂交技术以寡聚核苷酸为探针，分别检测各组MMP－1、MMP－2、MT1－MMP和TIMP－1 mRNA的表达情况。结果：发现MMP－1、MMP-2、MT1－MMP和TIMP－1 mRNA表达阳性的细胞主要是肝窦壁细胞（可能为增生的HSC）和少数肝细胞；MMP－2、MT1－MMP 和TIMP－1mRNA表达阳性细胞数随肝纤维化程度的增加而增多，相反，MMP－1 mRNA表达阳性细胞数则随肝纤维化程度的增加而减少。结论：HSC可能是肝组织内产生MMP－1、MMP－2、MT1－MMP和TIMP－1的主要细胞，在酒精性肝纤维化ECM沉积中起重要作用；MMP－1减少和TIMP－1增多可能是EMC沉积，尤其是I型胶原过量沉积的原因；而MMP－2和MT1－MMP增多的意义尚须进一步确定。