三裂叶海棠内生真菌的分离,鉴定及活性测定

目的:分离鉴定三裂叶海棠Malus sieboldii中内生真菌,并检验其抗病原真菌,抗肿瘤,抑制蛋白酶活性。方法:传统形态学和现代分子生物学方法鉴定菌种,采用杯碟法,MTT法,和BRpNA法测试真菌活性。结果:内生真菌按形态学归为22类,其中Non-sporulating,Alternaria,Colletotrichum,Aspergillus,Fusarium,Gliocladium,Cunninghamella是主要群落。通过对ITS rDNA测序,确定了有活性Non-sporulating的种属。活性测试结果显示30的菌株对至少1种植物病原菌有活性,菌株3,4分别具有细胞毒和蛋白酶抑制活性。结论:首次对三裂叶海棠的内生真菌进行了系统的分离、鉴定和活性筛选工作,证明三裂叶海棠是一种寄生活性内生真菌的潜在资源。     

Effect of Temperature on Electrochemically Assisted Deposition and Bioactivity of CaP Coatings on CpTi Grade 4

Calcium phosphate (CaP) coatings are able to improve the osseointegration process due to their chemical composition similar to that of bone tissues. Among the methods of producing CaP coatings, the electrochemically assisted deposition (ECAD) is particularly important due to high repeatability and the possibility of deposition at room temperature and neutral pH, which allows for the co-deposition of inorganic and organic components. In this work, the ECAD of CaP coatings from an acetate bath with a Ca:P ratio of 1.67, was developed. The effect of the ECAD conditions on CaP coatings deposited on commercially pure titanium grade 4 (CpTi G4) subjected to sandblasting and autoclaving was presented. The physicochemical characteristics of the ECAD-derived coatings was carried out using SEM, EDS, FTIR, 2D roughness profiles, and amplitude sensitive eddy current method. It was showed that amorphous calcium phosphate (ACP) coatings can be obtained at a potential −1.5 to −10 V for 10 to 60 min at 20 to 70 °C. The thickness and surface roughness of the ACP coatings were an increasing function of potential, time, and temperature. The obtained ACP coatings are a precursor in the process of apatite formation in a simulated body fluid. The optimal ACP coating for use in dentistry was deposited at a potential of −3 V for 30 min at 20 °C.     

The effects of electromagnetic pulses (EMP) on the bioactivity of insulin and a preliminary study of mechanism

Purpose:?To investigate the effects of electromagnetic pulse (EMP) exposure on the bioactivity of insulin and a preliminary mechanism for these effects.

Materials and methods:?A tapered parallel plate Gigahertz Transverse Electromagnetic (GTEM) cell with a flared rectangular coaxial transmission line was used to expose the insulin solution to EMP. Concurrent sham-exposed insulin solutions were used as a control. The effect of EMP-exposed insulin on fasting blood glucose levels of type I diabetes model mice, the effect of EMP on binding affinity between insulin and its receptor and the effect of EMP on insulin's fluorescence intensity were detected, respectively.

Results:?(i) After EMP exposure, compared with sham-exposed insulin, the bioactivity of insulin in decreasing fasting blood glucose levels in type I diabetes model mice was reduced significantly (p?=?0.023). (ii) Compared with sham-exposed insulin group, the percentage fluorescein isothiocyannate (FITC) labelling of HL-7702 cells was significantly reduced in the EMP-exposed insulin group (22.7–13.8%, respectively). (iii) Compared with sham-exposed insulin, the fluorescence intensity was significantly reduced in EMP-exposed insulin (p?<?0.001).

Conclusions:?EMP exposure significantly decreased the bioactivity of insulin to reduce the blood glucose levels in type I diabetic mice. This could be due to a decreased binding affinity between insulin and its receptor. This mechanism could involve an alteration of insulin's' conformation caused by EMP exposure.     

Bioeffects of mobile telephony radiation in relation to its intensity or distance from the antenna

Purpose:?To examine the bioactivity of GSM 900 and 1800 (Global System for Mobile Telecommunications) radiations, in relation to the distance from the antenna or to the radiation-field intensities.

Materials and methods:?Drosophila melanogaster adult insects were exposed to the radiation of a GSM 900/1800 mobile phone antenna at different distances ranging from 0 to 100?cm, and the effect on their reproductive capacity and cell death induction in the gonads by the use of TUNEL (Terminal deoxynucleotide transferase dUTP Nick End Labeling) assay, was studied.

Results:?These radiations/fields decreased the reproductive capacity by cell death induction, at all the different distances tested. The effect diminished with the distance/decreasing intensities. An increased bioactivity ‘window’ was revealed at distances of 20–30?cm from the mobile phone antenna, (radiation intensity around 10?μW/cm²) where the effect became highest, in relation to smaller or longer distances. The effect diminished considerably for distances longer than 40–50?cm and became not evident for distances longer than 1?m or radiation intensities smaller than 1?μW/cm².

Conclusions:?GSM bioactivity is highest for intensities down to less than 10?μW/cm² and still evident until 1?μW/cm² exhibiting ‘window’ effects.     

板蓝根化学成分与抗流感病毒神经氨酸酶活性相关性的探讨

目的探讨板蓝根化学成分与体外抗流感病毒神经氨酸酶(NA)活性的相关性。方法采用UPLC法建立不同产地板蓝根提取液的指纹图谱,并选取已知共有峰进行定量测定,采用试剂盒法测定药物抑制流感病毒NA活性,对化学信息和生物效应进行灰色关联分析和单因素相关分析,以探索其相关性。结果不同产地药材、不同提取方法得到的样品的化学成分量与生物效应均有一定的差异。UPLC指纹图谱各共有峰中已知峰(R,S)-告依春和尿苷与抑制流感病毒NA活性相关性较强,其中(R,S)-告依春量与生物效应显著相关。结论基于NA活性检测结果,初步明确了板蓝根化学成分量与生物效应的相关性,为板蓝根抗病毒有效成分的筛选和提取提供数据参考。     

肉芝软珊瑚属中二萜类化合物的化学及生物活性

二萜类化合物是肉芝软珊瑚（Sarcophyton）的特征性次生代谢产物,其多变的化学结构及广泛的生物学活性引起了化学及药理学研究领域的广泛关注,已成为海洋天然产物的研究热点之一。1997年印度学者对肉芝软珊瑚相关研究已经进行了较为详细的综述,本文对该属珊瑚1998年之后的研究进展进行了总结,包括来自12种已鉴定和13种未鉴定珊瑚的143个化合物,涵盖了1998年至今的54篇文献。     

人血小板衍生生长因子BB原核表达及生物学活性鉴定

目的 表达人血小板衍生生长因子(PDGF)BB蛋白并进行生物学活性鉴定.方法 基因扩增方法获得人PDGF-B基因;原核表达PDGF-BB蛋白,并纯化、复性;免疫印迹分析重组蛋白的免疫原性;应用培养的大鼠成骨细胞对其生物学活性进行鉴定.结果 扩增出327bp目的基因,与预期结果吻合,DNA序列分析正确.SDS-PAGE和免疫印记检测表明获得新生蛋白的分子量及免疫原性均与预期符合.体外细胞学鉴定表明,获得的rhPDGF-BB可明显促进大鼠成骨细胞的增殖和DNA复制,表明重组的PDGF-BB具有较好的生物学活性.结论 PDGF-B成熟肽基因克隆成功并成功地在大肠杆菌中实现了高表达.复性后细胞学MTT和FCM鉴定表明获得的rhPDGF-BB具有较好的生物学活性,为生产活性PDGF-BB蛋白及其在促进骨组织和创伤修复方面的进一步功能研究奠定了基础.     

高活力人降钙素类似物vhCT的免疫原性研究

本研究用固相多肽合成法合成人降钙素类似物vhCT ,产物纯度达到等电聚焦均一 ,质谱测定分子量精确。生物活性为天然人降钙素的 2 0～ 2 5倍。用放射免疫法测定vhCT能与识别天然人降钙素的抗体起反应 ,产生IgG抗体的免疫原性随偶联的不同载体而有差异。但在BALB/C5 7小鼠体内不引起IgE增高。提示vhCT不产生IgE介导的过敏反应 ,具有药物应用前景。     

唇形科香茶菜属二萜类化合物的生物活性研究进展

香茶菜属植物资源丰富,所含化学成分以二萜类化合物为主。二萜类化合物具有广泛的生物活性,以抗肿瘤、抗炎和抑菌活性最为显著。通过生物活性的广泛筛选和作用机制研究,该类化合物结构的活性基团和作甩机制被逐步揭示,而这些研究结果为香茶菜属植物进一步研究开发提供了科学依据。本文对该类化合物的研究进展作一综述。     

泡球蚴长期保存后生物活性的研究

目的继发性泡球蚴经液氮冻存后传代健康小鼠,观察其体内泡球蚴的生长情况并判定其生物活性,以探讨泡球蚴保种传代的新方法。方法将继发性感染泡球蚴的小鼠,液氮冻存7d后,常规复苏剖取包囊接种健康小鼠,生长两个月后颈椎脱臼处死,剖检并与常规接种方法相比较,从以下方面评价冻存效果:(1)大体观察及测量包囊湿重;(2)普通光学显微镜及透射电子显微镜观察组织学结构及超微结构;(3)检测包囊囊液中总蛋白含量、血清中特异性免疫球蛋白活动状态等免疫学指标;(4)检测血清碱性磷酸酶及囊液中钙离子含量等生化指标。结果液氮低温冻存后泡球蚴所接种试验组小鼠与常规接种组小鼠体内泡球蚴在包囊湿重、包囊组织结构、囊液蛋白及钙离子含量、血清碱性磷酸酶及特异性免疫球蛋白活动状态等方面均无显著差异(P>0.05)。结论液氮冻存后泡球蚴仍具有感染小鼠的能力,且接种后所生长泡球蚴组织与常规接种泡球蚴组织生物活性无显著差异。液氮冻存可以长期保存泡球蚴组织的活性。