Protein tyrosine phosphatase controls breast cancer invasion through the expression of matrix metalloproteinase-9

The expression of matrix metalloproteinases (MMPs) produced by cancer cells has been associated with the high potential of metastasis in several human carcinomas, including breast cancer. Several pieces of evidence demonstrate that protein tyrosine phosphatases (PTP) have functions that promote cell migration and metastasis in breast cancer. We analyzed whether PTP inhibitor might control breast cancer invasion through MMP expression. Herein, we investigate the effect of 4-hydroxy-3,3-dimethyl-2H benzo[g]indole-2,5(3H)-dione (BVT948), a novel PTP inhibitor, on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion in MCF-7 cells. The expression of MMP-9 and cell invasion increased after TPA treatment, whereas TPA-induced MMP-9 expression and cell invasion were decreased by BVT948 pretreatment. Also, BVT948 suppressed NF-κB activation in TPA-treated MCF-7 cells. However, BVT948 didn’t block TPA-induced AP-1 activation in MCF-7 cells. Our results suggest that the PTP inhibitor blocks breast cancer invasion via suppression of the expression of MMP-9. [BMB Reports 2013; 46(11): 533-538]     

Binding model for eriodictyol to Jun-N terminal kinase and its anti-inflammatory signaling pathway

The anti-inflammatory activity of eriodictyol and its mode of action were investigated. Eriodictyol suppressed tumor necrosis factor (mTNF)-α, inducible nitric oxide synthase (miNOS), interleukin (mIL)-6, macrophage inflammatory protein (mMIP)-1, and mMIP-2 cytokine release in LPS-stimulated macrophages. We found that the anti-inflammatory cascade of eriodictyol is mediated through the Toll-like Receptor (TLR)4/CD14, p38 mitogen-activated protein kinases (MAPK), extracellular-signalregulated kinase (ERK), Jun-N terminal kinase (JNK), and cyclooxygenase (COX)-2 pathway. Fluorescence quenching and saturation-transfer difference (STD) NMR experiments showed that eriodictyol exhibits good binding affinity to JNK, 8.79 × 10⁵ M^-1. Based on a docking study, we propose a model of eriodictyol and JNK binding, in which eriodictyol forms 3 hydrogen bonds with the side chains of Lys55, Met111, and Asp169 in JNK, and in which the hydroxyl groups of the B ring play key roles in binding interactions with JNK. Therefore, eriodictyol may be a potent anti-inflammatory inhibitor of JNK. [BMB Reports 2013; 46(12): 594-599]     

功能性包涵体的研究进展

利用原核系统表达外源重组蛋白的一个特点是表达蛋白多以包涵体形式存在。在过去人们一直认为包涵体是错误折叠、无生物活性的蛋白,需要经过变复性的过程重新获得有生物活性、可溶的蛋白,因而变复性条件的摸索迄今仍然是该领域的难点。但近几年的研究表明包涵体并非都是无生物活性的,功能性包涵体(或者称为非传统意义包涵体) 概念的提出是该领域的一个重大研究进展。由于功能性包涵体本身具有生物活性,可在非变性条件下提取,目前已经在生命科学的基础研究、生物制药、生物材料、生物催化等领域展现出良好的应用前景。重点从功能性包涵体的定义、形成机理、提取条件等近期研究进展进行综述,以期为原核细胞表达和工业生产重组蛋白药物提供新的思路。     

高龄老年心力衰竭患者临床特点分析

目的：通过对不同年龄组心力衰竭常见临床表现进行对比分析,寻找出老年心力衰竭的特点,为临床诊断和治疗老年特别是高龄老年（〉80岁）心力衰竭提供依据。方法：我院专职人员采取回顾性调查方法,记录所选病例相关的数据：一般临床资料、基础心脏疾病、诱发因素、伴随疾病、临床表现、相关实验室检验检查情况、药物治疗具体种类、转归情况等;根据年龄分为3组：246例60—69岁组,平均年龄（64．28±3．0）2V;215例70-79岁组,平均年龄（74．19±2．85）岁;71例〉80岁组,平均年龄（84±3．34）岁。运用计算机软件Excel建立老年心衰患者资料数据库,SPSS13．0for：windows软件包进行统计分析。结果：1）随着年龄增加,心衰典型的临床表现减少,特别是高龄心衰患者,其临床表现极不典型,心力衰竭程度较重,容易在短期内出现重要器官的严重并发症;2）高龄老年人心衰以冠心病、高血压病为主要病因,随年龄增加,多病因心衰比例在上升;3）我院高龄老年人心衰的治疗以利尿剂、洋地黄类、硝酸醋类药物为主。结论：高龄老年人心力衰竭具有明确病因、程度重,症状不典型,具有严重并发症,治疗相对规范的临床特点。     

1O2-Mediated and EXECUTER-Dependent Retrograde Plastid-to-Nucleus Signaling in Norflurazon-Treated Seedlings of Arabidopsis thaliana

Chloroplast development depends on the synthesis and import of a large number of nuclear-encoded pro- teins. The synthesis of some of these proteins is affected by the functional state of the plastid via a process known as retrograde signaling. Retrograde plastid-to-nucleus signaling has been often characterized in seedlings of Arabidopsis thaliana exposed to norflurazon （NF）, an inhibitor of carotenoid biosynthesis. Results of this work suggested that, throughout seedling development, a factor is released from the plastid to the cytoplasm that indicates a perturbation of plastid homeostasis and represses nuclear genes required for normal chloroplast development. The identity of this factor is still under debate. Reactive oxygen species （ROS） were among the candidates discussed as possible retrograde signals in NF-treated plants. In the present work, this proposed role of ROS has been analyzed. In seedlings grown from the very beginning in the presence of NF, ROS-dependent signaling was not detectable, whereas, in seedlings first exposed to NF after light-dependent chloroplast formation had been completed, enhanced ROS production occurred and, among oth- ers, 1O2-mediated and EXECUTER-dependent retrograde signaling was induced. Hence, depending on the developmental stage at which plants are exposed to NF, different retrograde signaling pathways may be activated, some of which are also active in non-treated plants under light stress.     

HIV-1整合酶链转移反应抑制剂的荧光筛选方法

整合酶被认为是抗HIV-1药物研究的理想靶点之一。为了建立便捷高效的整合酶链转移反应抑制剂筛选方法,首先将HIV-1整合酶原核表达载体pNL-IN转化入大肠杆菌感受态细胞BL21(DE3)进行原核表达,并用镍琼脂糖凝胶进行亲和纯化,获得了纯度和活性均较高的整合酶重组蛋白;然后设计了生物素标记的供体DNA和FITC标记的靶DNA,用链霉亲和素磁珠捕获反应体系中的DNA产物;最后用荧光分析仪检测DNA产物的荧光信号,并计算待测样品的抑制率。用已知整合酶抑制剂S-1360和MK-0518对筛选方法进行了验证,测定结果与已有实验数据相当,表明本筛选方法能够有效应用于HIV-1整合酶链转移反应抑制剂的筛选。与现有的整合酶链转移反应抑制剂筛选方法相比,本筛选方法步骤更为简化、耗时更短、成本更低。     

ITS-RFLP在白灵菇种质资源鉴定中的应用

为快速鉴别白灵菇种质资源的真伪,对58个供试菌株进行ITS特异性扩增,根据遗传差异选择菌株进行ITS克隆测序,经ITS-RFLP分析和ITS序列分析得知:58个供试菌株中,Pl.n0010、Pl.n0020、Pl.n0025、Pl.n0041这4个菌株为杏鲍菇;菌株Pl.n0037是糙皮侧耳;余下53个菌株为白灵菇。结果表明:ITS-RFLP可应用于白灵菇与杏鲍菇菌株间的鉴定。     

A Novel High‐Energy Hybrid Supercapacitor with an Anatase TiO2–Reduced Graphene Oxide Anode and an Activated Carbon Cathode

A hybrid supercapacitor with high energy and power densities is reported. It comprises a composite anode of anatase TiO₂ and reduced graphene oxide and an activated carbon cathode in a non‐aqueous electrolyte. While intercalation compounds can provide high energy typically at the expense of power, the anatase TiO₂ nanoparticles are able to sustain both high energy and power in the hybrid supercapacitor. At a voltage range from 1.0 to 3.0 V, 42 W h kg^?1 of energy is achieved at 800 W kg^?1. Even at a 4‐s charge/discharge rate, an energy density as high as 8.9 W h kg^?1 can be retained. The high energy and power of this hybrid supercapacitor bridges the gap between conventional batteries with high energy and low power and supercapacitors with high power and low energy.