脂肪细胞新蛋白My027原核表达、纯化及生物活性研究

目的通过原核表达获得大量脂肪新蛋白质My027,并在体外初步研究其生物活性。方法RT-PCR法扩增出My027片段,插入原核表达载体pGEX-4T-2,构建质粒pGEX-My027。转化BL-21菌,IPTG低温诱导表达融合蛋白,经亲和层析法获得融合蛋白,利用SDS-PAGE、Western印迹及质谱进行鉴定。在还原性谷胱甘肽存在的条件下,将纯化得到的融合蛋白作用于乙二醛酶Ⅰ的底物甲基乙二醛,通过分光光度法检测产物乳酸谷胱甘肽的生成。结果融合蛋白以水溶形式分泌于大肠埃希菌BL-21胞浆中,纯化后的目的蛋白SDS-PAGE、Western印迹及质谱证实高效表达,氨基酸序列正确。结论人脂肪细胞新蛋白质My027在pGEX-4T-2原核表达载体中可获高效表达,所纯化蛋白具有类似于乙二醛酶Ⅰ的作用。     

Substance P and somatostatin metabolism in sympathetic and special sensory ganglia in vitro

Mechanisms regulating the content of the putative peptide transmitters, substance P and somatostatin, were examined in several neuronal populations in culture. Substance P levels increased more than 25-fold within 48 h in sympathetic neurons in the explanted rat superior cervical ganglion, and remained elevated for 4 weeks. Identity of the peptide was authenticated by combined high pressure liquid chromatography-radioimmunoassay. Veratridine prevented the increase of substance P in vitro, and tetrodotoxin blocked the veratridine effect, suggesting that sodium ion influx and membrane depolarization prevent peptide elevation. Veratridine (or potassium)-induced membrane depolarization released substance P into the culture medium through a calcium-dependent process. Consequently, at least some veratridine effects are attributable to release and subsequent depletion of ganglion peptide. However, the inhibitory effects of veratridine were far greater than could be accounted for by the quantity of peptide released, suggesting a separate influence on net synthesis (synthesis less catabolism) of substance P. Viewed in conjunction with previous in vivo studies, our observations suggest that trans-synaptic impulses, through the mediation of postsynaptic sodium flux, release substance P from sympathetic neurons and also regulate intracellular peptide metabolism. To determine whether the processes regulating substance P in sympathetic neurons reflect generalized mechanisms, a different peptide, somatostatin, was examined in sympathetic neurons; moreover, substance P was examined in a different neuronal population, special sensory neurons in the nodose ganglion. Substance P levels increased significantly in both sympathetic and sensory neurons after explantation, and somatostatin levels increased in sympathetic neurons. In each instance, the increase was dependent upon the presence of the calcium ions. Moreover, these increases were all prevented by veratridine, in a tetrodotoxin-sensitive manner. Our observations suggest that common regulatory mechanisms govern peptide transmitter metabolism in diverse neuronal populations.     

Some kinetic features of membrane-bound monoamine oxidase

Initial reaction-velocity versus substrate-concentration curves for serotonin oxidation catalyzed by monoamine oxidase (MAO) from fragments of rat liver or bovine brain mitochondrial membranes have a complex, nonhyperbolic shape; this is regarded as a kinetic manifestation of substrate cooperativeness for membrane-bound MAO. The possibility of interaction between different types of MAO based on conformational changes in the membrane itself is discussed.Scientific-Research Institute for Biological Trials of Chemical Compounds, Ministry of the Medical Industry of the USSR. Institute of Biological Medical Chemistry, Academy of Medical Sciences of the USSR. All-Union Vitamin Scientific-Research Institute, Ministry of the Medical Industry of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Orekhovich.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 3, pp. 288–289, March, 1977.     

Studies on the mammary tumor-inhibiting effects of diethylstilbestrol and its mono- and diphosphate

Summary Diethylstilbestrol (DES), diethylstilbestrol monophosphate (DES-MP) and diethylstilbestrol diphosphate (DES-DP) were tested for their estrogen receptor affinity, estrogenic potency and mammary tumor-inhibiting activity in vitro and in vivo. DES had a much higher receptor binding affinity than its mono-or diphosphate. All three compounds inhibited the growth of the hormone-dependent MCF-7 and hormone-independent MDA-MB 231 breast cancer line only at relatively high concentrations. The estrogenic potency in the immature mouse uterine weight test decreased in the order DES>DES-MPDES-DP. The hormone-dependent MXT mammary tumor of the mouse was inhibited by all three compounds at a dosage of 1.0 mg/kg per week. At a dose of 0.01 mg/kg, DES, DES-MP, and DES-DP stimulated the tumor growth. Thus, for the first time, a biphasic effect on tumor growth was demonstrated in intact mature animals. As the effects of all three compounds were similar in this assay, a cleavage of the phosphate groups is likely. A decrease in estrogenic potency concomitant with a retained antitumor effect of DES-MP and DES-DP compared to DES was not demonstrable in the mature mouse using the MXT assay, only in the uterotrophic test in the immature mouse.Dedicated to Professor Dietrich Schmähl on occasion of his 60th birthdaySupported by the Deutsche Forschungsgemeinschaft and by the Verband der Chemischen Industrie, Fonds der Chemischen Industrie. The authors thank Dr. Weigert, Asta-Werke AG, Degussa Pharma Gruppe, Bielefeld, FRG, for the analysis of DES-MP and DP     

双歧杆菌QJ 405和乳酸杆菌QJ 405的生物学特征及鉴定

目的：观察从健康核潜艇艇员正常粪便中分离出的双歧杆菌QJ405和乳酸杆菌QJ405的生物学特征,判定其是否符合益生菌要求。方法：分析细菌的形态学和生理生化特征。采用数值分类法（API20A）的化学分类法（气相色谱分析）进行种属鉴定。抗生素敏感试验采用ATB法。结果：两株菌分别鉴定为长双杆菌和唾液乳酸杆菌唾液亚种,两菌代谢发酵碳水化合物均可产生大量乙酸、乳酸,对多种抗生素表现敏感。结论：双歧杆菌QJ405和乳酸杆菌QJ405的来源和部分生物活性符合益生菌的要求。     

诊断卵巢恶性肿瘤最佳标志群的研究

目的研究22种肿瘤标志(TM)对诊断卵巢恶性肿瘤(OMN)的价值,选择最佳诊断标志群.方法用高压液相色谱法、自动生化仪检测法、酶联免疫法检测.结果单项TM的敏感性≥60%者分别为腐胺(100%)、精脒(84%)、CA125(80%)、唾液酸(SA)(70.4%)、铁蛋白(61.2%)、肿瘤特异生长因子(TS-GF)(60.9%)和CA153(60%).有效率≥80%者分别是TSGF(88.6%)、精胺(86.6%)、精脒(83.8%)、CA153(81.2%)、SA(81.1%)、腐胺(81.0%)和CA125(80%).最佳标志群为CA125、TSGF和SA.结论CA125是诊断OMN最敏感的TM,其次是SA、铁蛋白和TSGF.TM联合测定能提高诊断的有效性,其中以CA125、TSGF和SA联合测定效果较好.     

热应激蛋白70抗体滴度作为二硫化碳接触的生物标记物的研究

目的 :了解二硫化碳接触工人的血清热应激蛋白 70 (HSP 70 )抗体滴度及探讨其作为CS2 接触的分子生物标记物的可行性。方法 :选择某化纤厂 79名工人 ,5 4名为接触组 ,2 5名为对照组。用Westernblot ELISA法对工人血清HSP 70抗体水平进行了检测。采用Logistic回归分析技术 ,分析了HSP 70抗体与CS2 接触之间的关系。结果 :抗体各滴度接触组工人血清HSP 70抗体阳性率明显高于对照组 ,有非常显著意义 (P <0 .0 1)。采用Logistic回归分析控制了因素的混杂作用后 ,这种联系仍然存在。结论 :血清HSP 70抗体滴度可反映CS2 的接触状况。以血清HSP 70抗体滴度作为分子生物学标记物 ,对CS2 接触者进行健康监护有重要意义。     

Monitoring of biological responses of tumor cells after irradiation with99mTc-MIBI — Anin vitro study

Summary To explore the possibility to employ^99mTc-MIBI to monitor biological response of tumor cells after irradiation and to observe the relation between the radiation doses and the uptake levels of^99mTc-MIBI in tumor cells, the cells were irradiated with a single dose of 2 Gy, 10 Gy and 20 Gy respectively. The uptake of^99mTc-MIBI in each dosage group was determined before and 24, 48, 72 h after irradiation respectively. Apoptosis index (AI), plating efficiency (PE) of tumor cells was simultaneously determined. There was a positive correlation between uptake levels of^99mc-MIBI and AI(r = −0.91,P< 0.05). A negative correlation was noted between the uptake levels and PE (r = −0.86,P< 0.05). It is suggested that^99mTc-MIBI may be used as a tracer to monitor the change of viability state of tumor cells after being irradiated with different doses.     

Dark Tea: A popular beverage with possible medicinal application

Tea is a famous beverage that is produced from leaves of Camellia sinensis. Amongst the six major tea categories in China, dark tea is the only one that involves microbial fermentation in the manufacturing process, which contributes unique flavors and functions for the tea. In the recent decade, the reports about the biofunctions of dark teas have increased rapidly. Therefore it may be the proper time to consider dark tea as one potential homology of medicine and food. In this viewpoint, our current understanding of the chemical constituents, biological activities and possible health beneficial effects of dark teas were introduced. Some future directions and challenges to the development perspectives of dark teas were also discussed.     

基于抗肝纤维化生物活性及近红外谱效相关的鳖甲质量评价研究

目的 从鳖甲临床抗肝纤维化功效出发并结合近红外光谱,探索建立关联抗肝纤维化活性的鳖甲质量生物活性评价方法。方法 建立转化生长因子-β1（transforming growth factor-β1,TGF-β1）诱导的LX-2肝纤维化细胞模型,采用qRT-PCR检测鳖甲对I型胶原（type I collagen,COL1）mRNA表达的影响,计算鳖甲对COL1 mRNA相对表达量的抑制率;采用Western blotting检测鳖甲对COL1蛋白表达的影响,以评价鳖甲在细胞模型上的抗肝纤维化生物活性。采集并处理不同批次鳖甲药材的近红外光谱数据,通过谱-效相关分析探究鳖甲药材近红外光谱数据与其抗肝纤维化活性的相关性,筛选活性波段,建立鳖甲的效应近红外谱,以效应近红外谱下面积评价鳖甲药材的质量。结果 体外实验表明,与模型组比较,鳖甲水提物（water extract of Trionycis Carapax,WECT）处理组细胞中COL1 mRNA与蛋白表达水平显著下调（P＜0.05、0.01）;基于谱-效相关分析,共筛选得到R＞0.6、P＜0.05且波数大于8 cm⁻¹的活性波段3个,分别为5226～5235 cm⁻¹、5943～6071 cm⁻¹与6379～6396 cm⁻¹,以3个活性波段下面积为指标,建立鳖甲药材的效应近红外谱,计算各特征波段下面积和,并分析其与生物活性的相关性,两者相关系数R为0.813 53。结论 WECT可抑制LX-2细胞外基质的产生来治疗肝纤维化;效应波谱下面积和（5226～5235 cm⁻¹、5943～6071 cm⁻¹与6379～6396 cm⁻¹）作为鳖甲药材的质量评价系数,用于评价鳖甲药材的质量,可区分不同批次鳖甲药材的抗肝纤维化活性。