线粒体靶向抗氧化剂MitoQ的抗肿瘤效应

采用噻唑蓝(MTT)法检测不同浓度MitoQ对肝癌HepG2细胞的毒性;凋亡诱导实验研究不同浓度MitoQ对HepG2细胞凋亡率的影响;裸鼠移植瘤模型研究MitoQ对肝癌HepG2荷瘤小鼠的抑瘤作用。结果表明,MitoQ对肝癌HepG2细胞的抑制作用随着浓度而增加;给药组凋亡率显著高于对照组(p0.01);MitoQ在1、5、10mg/kg剂量给药10d后对小鼠的肿瘤生长均有抑制作用,与对照组相比,10mg/kg剂量组肿瘤体积(p0.01)和肿瘤质量(p0.05)均有显著性差异。结果提示,MitoQ在体内体外均具有抑制肝癌HepG2细胞生长的作用。     

188Re标记抗人前列腺癌单克隆抗体及其在荷瘤裸鼠体内的放射性分布

为探讨188Re标记抗前列腺癌单克隆抗体7E11C5.3的方法及其生物学分布,采用2-巯基乙醇直接还原法制备188Re-7E11C5.3标记物,常规测定标记率和免疫活性,在荷瘤裸鼠体内检测标记物的生物学分布.结果显示,188Re-7E11C5.3的标记率为(93.16±2.18)%,免疫活性分数为(74.86±1.86)%;经尾静脉注入裸鼠体内后,肿瘤组织摄取率在24h达高峰,非肿瘤组织在4h摄取率较高,以后均随时间延长逐步降低;血液放射性清除迅速;24h时T/NT值达最大,至72h仍可保持在较高水平.结果表明,188Re-7E11C5.3在裸鼠体内对前列腺癌移植瘤有良好的靶向定位作用,可用于前列腺癌放射免疫显像和治疗研究.     

[35S]-甲硫氨酸掺入法测定某些补益药活性成分对 Aβ分泌速率的影响

[35S]-甲硫氨酸掺入法测定细胞Aβ分泌速率,观察知母活性成分ZMS和黄芪活性成分AST和HT,及两药合用对Aβ生成速率的影响.用[35S]-甲硫氨酸标记转染APP695基因的细胞,所获细胞上清以Aβ22-35单克隆抗体进行免疫共沉淀,结合Western印迹法,以配对对照(加载体)的Aβ条带灰度值为l,计算各用药组灰度的相对强度.本方法能稳定地测到细胞在24-72 h内分泌的Aβ量,同一受试样品在不同批实验中的变异(CV)在17%-32%之间.在培养液中中药活性成分的浓度为1×l0-5mo1/L时,受试物质中AST及ZMs AST合用对Aβ的分泌速率有明显抑制作用(P＜0.01).另两种受试物则无作用.黄芪活性成分AsT有抑制Aβ分泌的作用,ZMs与AST两药合用作用更为显著.     

~(188)Re-7E11C5.3在前列腺癌裸鼠模型中的放射免疫治疗研究

为探讨188Re标记前列腺特异膜抗原单克隆抗体7E11C5.3放射免疫治疗前列腺癌裸鼠移植瘤的效果,将32只荷LNCaP移植瘤裸鼠随机分成4组:188Re-7E11C5.3组、188Re-mIgG组、188ReO4-组和对照组,采用5.55 MBq单剂量尾静脉注射给药,连续4周观察裸鼠体重和肿瘤体积变化.实验结束后,检测裸鼠血清PSA水平,测定移植瘤重量,计算抑瘤率.结果显示,188Re-7E11C5.3组的瘤体重量和动物血清PSA水平均小予对照组(P＜0.01),抑瘤率为60.7%.188Re-mIgG组和188ReO4-组的瘤体重量和裸鼠血清PSA水平与对照组相比差异均无统计学意义(P＞0.05).结果表明,188Re-7E11C5.3能有效抑制前列腺癌裸鼠移植瘤的生长,具有较好的抗前列腺癌应用前景.     

131Ⅰ标记B细胞淋巴瘤Fab抗体荷瘤裸鼠治疗及磁共振影像分析

将荷人B细胞淋巴瘤裸鼠分为对照组、Fab抗体组、单次注射组和重复注射组,尾静脉注射131Ⅰ-Fab抗体后进行ECT显像;每隔5 d用MRI结合显微镜线圈检测荷瘤裸鼠的肿瘤大小.注射后25 d,取出肿瘤,进行病理分析、流式细胞术和电镜检测细胞凋亡.结果显示,131Ⅰ-Fab抗体静脉注射后8 h在肿瘤局部浓集明显,瘤体清晰显像;Fab组5 d内具有抑制肿瘤生长作用,凋亡率为(2.48±0.6)%;单次131Ⅰ-Fab注射组早期抑制肿瘤生长较明显,肿瘤生长出现平台期,凋亡率为(10.67±1.6)%;131Ⅰ-Fab抗体重复注射组抑制肿瘤生长作用明显,肿瘤局部坏死脱落,凋亡率为(14.00±1.9)%.病理结果显示两注射组均可见组织坏死.MRI图像与病理结果相符,通过造影剂增强可提供较准确的病理信息.表明131Ⅰ-Fab抗体具有早期ECT肿瘤显像、瘤体准确定位,并通过致凋亡和直接促使细胞死亡的作用而有效抑制肿瘤生长,大型高场强MRI可为小动物模型实验提供有效、无创、动态的监测.     

188Re标记抗CEA单克隆抗体及荷瘤裸鼠治疗实验研究

为建立18 8Re标记抗癌胚抗原 (CEA)单克隆抗体 (McAb )C50 的直接标记方法 ,探讨其标记条件 ,用抗坏血酸还原McAb ,并以葡萄糖酸钠为中间螯合剂 ,以氯化亚锡作还原剂 ,用188Re标记C50 。观察188Re标记McAb的体外稳定性 ,探讨还原剂SnCl2 浓度、螯合剂葡萄糖酸钠浓度、抗体浓度、加入抗体间隔的时间对标记物放化纯度的影响。SPECT显像观察荷瘤裸鼠瘤内注射188Re-C50 后放射性分布 ,对治疗后的瘤体行病理观察。实验结果显示 ,188Re标记C50 的合适条件为 :2 .2— 4 .0g/LSnCl2 、0 .3mol/L葡萄糖酸钠溶液、2 .5× 10 5— 5 .0× 10 5mol/LMcAb ,反应 2h后放化纯度可达 90 %。荷瘤裸鼠瘤内注射188Re -C50 后 ,放射性集中在瘤内 ,2周后瘤体明显缩小 ,镜下观察到肿瘤细胞破裂 ,坏死。     

NGR短肽的188Re标记及其在荷瘤裸鼠体内的生物分布和SPECT显像

采用¹⁸⁸Re标记含有天冬酰胺、甘氨酸、精氨酸（Asn-Gly-Arg,NGR）序列的肿瘤血管靶向性短肽,得到¹⁸⁸Re-NGR,观察了¹⁸⁸Re-NGR在荷HepG2肝癌细胞严重联合免疫缺陷（Severe Combined Immunodeficiency,SCID）裸鼠肿瘤模型中的生物分布,并对其进行了SPECT显像。结果显示,¹⁸⁸Re-NGR的标记率>85%,放化纯度>90%。¹⁸⁸Re-NGR在肿瘤模型鼠体内的生物分布显示,注射¹⁸⁸Re-NGR后12 h,肿瘤放射性摄取达最高,为(4.62±0.71)%ID/g,24 h时仍有(2.01±0.38)%ID/g,说明标记物在肿瘤内停留时间较长;竞争性抑制组中,12 h肿瘤放射性摄取为(1.43±0.61)%ID/g,明显低于实验组。肿瘤与肌肉组织的放射性摄取比(T/NT) 12 h为4.76。注射后1 h肿瘤可显像,4～8 h显像逐渐清晰,12 h时更为清晰。以上结果提示,¹⁸⁸Re-NGR具有良好的肿瘤血管靶向性。     

~(131)I-B2-S22-AFA对HER-2高表达乳腺癌细胞的杀伤作用

人类表皮生长因子受体2(Human Epidermal Growth Factor Receptor 2,HER-2)是乳腺癌最重要的致病基因。本文探讨~(131)I标记的HER-2特异结合小分子模拟肽B2-S22-AFA对乳腺癌细胞的特异性杀伤作用。采用溴代琥珀酰亚胺法(N-Bromide Succinimide,NBS)进行~(131)I标记B2-S22-AFA,测定标记率、放化纯度、稳定性及免疫活性。用Western Blot法和免疫组化法测定人乳腺癌SKBR3及MDA-MB-231Her-2细胞HER-2表达,观察不同浓度表皮生长因子(Epidermal Growth Factor,EGF)条件下B2-S22-AFA对细胞生长的抑制率。设B2-S22-AFA组(B2-S22-AFA终浓度1μg·mL~(–1))、~(131)I-B2-S22-AFA组(~(131)I-B2-S22-AFA终浓度144 kBq·μg~(–1)·mL)、~(131)I组(~(131)I终浓度144 kBq·mL~(–1))、阴性对照组及试剂空白组,每组EGF终浓度均5.0 pg·mL~(–1),采用四唑盐比色法(Methyl Thiazolyl Tetrazolium,MTT)测定SKBR3和MDA-MB-231细胞增殖活性,观察~(131)I-B2-S22-AFA、B2-S22-AFA及~(131)I作用不同时间对两种细胞生长的抑制率。结果显示,HER-2在SKBR3细胞呈强阳性表达,在MDA-MB-231细胞呈弱(或低)表达。~(131)I-B2-S22-AFA标记率、放化纯度及比活度分别为64.8%–79.6%、95.0%–97.6%、151.7 MBq·mg~(–1),在37°C血清中放置4 h、12 h、24 h、48 h、72 h的放化纯度分别95.4%、93.5%、91.4%、88.2%、77.4%,~(131)I-B2-S22-AFA与SKBR3细胞及MDA-MB-231细胞的最大结合率分别(66.47±3.24)%和(3.89±0.81)%(3次)。当EGF存在时,B2-S22-AFA可明显抑制SKBR3细胞生长;无EGF时,B2-S22-AFA无此作用。~(131)I-B2-S22-AFA对SKBR3细胞的杀伤作用较B2-S22-AFA和~(131)I明显增强(均p0.05),B2-S22-AFA对SKBR3细胞杀伤作用显著高于~(131)I(p0.05),~(131)I-B2-S22-AFA和B2-S22-AFA对MDA-MB-231细胞均无杀伤作用。综上所述,~(131)I-B2-S22-AFA可显著加强、加速B2-S22-AFA对HER-2高表达乳腺癌细胞的特异性杀伤作用。     

直接法制备188Re-碘化油

探讨直接法制备188Re-碘化油的实验条件及标记物性质.在温度为75～120℃和不同实验条件下,直接标记法制备188>Re-碘化油,观测标记物标记率在室温和37℃人血浆体系中随时间的变化情况;采用红外光谱仪分析标记对碘化油分子结构的影响;用肿瘤模型动物显像验证碘油对188Re的包埋效果,以及在生物体内的稳定性半定量分析.直接法制备188Re-碘化油,在最佳标记条件下,标记物标记率可达(99.1±0.4)%;标记物在室温和37℃人血浆体系中放置3 d,标记率可保持在(90.9±1.9)%和(92.8±1.2)%.红外光谱结果显示本标记方法不改变碘化油的分子结构;荷S180骨肉瘤鼠显像表明,瘤内注射标记物48 h后,肿瘤部位仍有明显的放射性浓聚.188Re直接标记碘化油易于操作,标记物标记率高,体外稳定性好,碘油对放射性核素铼的包裹效果良好.     

槲皮素对人宫颈癌HeLa细胞辐射敏感性的影响

为观察槲皮素对人宫颈癌细胞HeLa增殖及其放射敏感性的影响,以人宫颈癌细胞株HeLa为研究对象,以MTT比色法和克隆形成实验检测槲皮素对HeLa细胞生长的抑制作用,并以克隆形成实验观察槲皮素对HeLa细胞株放射敏感性的影响。结果表明槲皮素能明显抑制人宫颈癌HeLa细胞增殖,存在剂量依赖和时间依赖性。克隆形成实验显示槲皮素对HeLa细胞的作用可分为两部分,一部分抑制HeLa细胞增殖,另一部分为诱导HeLa细胞死亡。克隆形成实验也显示槲皮素联合X射线照射能著显降低照射后HeLa细胞的存活率。本实验研究认为槲皮素具有放射增敏作用,为临床开展放射线联合槲皮素治疗肿瘤的研究提供了实验依据。     

Preparation of Zn/TiO2 powder and its photocatalytic performance for oxidation of P-nitrophenol

Zn-doped TiO2 catalysts were prepared using a sol-gel method and characterized by XPS,UV-Vis, BET, XRD in this study. Under the irradiation of simulant sunlight, the photocatalytic activity for the degradation of p-nitrophenol was studied too. After irradiation for 2.5 h, the degradation percentage of p-nitrophenol could rise to more than 80 %. The results showed that the spectrum absorption band edge of Zn/TiO2 powder does not broaden obviously comparing with pure TiO2 powder. Zinc exists as Zn （11）. When calcined at 973 K, there is a new phase as ZnTiO3 in Zn/TiO2 catalyst. The order of photocatalytic activity of Zn/TiO2 catalysts calcined at different temperatures for p-nitrophenol is 773 K 〉 673 K 〉 873 K 〉 573 K 〉 973 K and the photocatalytic activity of Zn/TiO2 catalyst calcined at 773 K is better than TiO2 catalysts heated at the same temperature, and outclasses that of commercial TiO2 catalyst. It also showed that the photocatalytic degradation of p-nitrophenol follows first-order kinetics under the irradiation of simulant sunlight.     

Current status of radiation therapy for prostate cancer

Radiotherapy for the treatment of prostate cancer has been extensively explored in the past. Along with the comprehensive understanding of the biology of prostate cancer and rapid advances in terms of technology, the out- come of treatment for the patients with prostate cancer has improved. The authors review radiotherapy as the primary treatment for the disease, with particular emphasis on the technological advances from both the radiobiological and radiophysics aspects. Nonconventional fractionated irradiation like hyper- or hypo-fractionation has been imple- mented in the clinic, the final results still need to be confirmed in the future. Technological advances like IMRT, IGRT, in the last two decades have significantly improved the delivery of external radiotherapy to the prostate. This has re- sulted in an overall increase in the total dose that can be safely delivered to the prostate, which has led to modest im- provements in the biochemical outcome. However, establishing the standard therapy for prostate cancer remains con- troversial. It is hoped that the next decades will bring continued advances in the development of biologicals that will further improve current clinical outcomes.     

The control system for SSRF injection and extraction

This paper introduces the injection and extraction control system design for SSRF,which is a distributed control system aimed at stability and reliability of the pulse power supplies,PPS(Personnel Protection System)and MPS(Machine Protection System).The hardware environment is mainly based on PLC(Programmable Logic Con- troller),and ARM(Advanced RISC Machine)is also applied for studying stability of the power supplies.WinCC and EPICS(Experimental Physics and Industrial Control System)have been selected as the platforms of SCADA(Super- visory Control and Data Acquisition).For unifying the interfacing to the control computer,all front-end equipments are connected via Industrial Ethemet.     

水平管内含空气蒸汽强制对流冷凝换热模型研究

为研究含空气蒸汽在水平管内强制对流冷凝换热特性,基于对传热传质过程的分析,建立了管内为环状流与波状流条件下的流动冷凝换热模型。从潜热、显热和液膜3个环节对整个换热过程进行建模,最终得到计算局部冷凝换热系数的理论关系式。模型预测结果与实验数据的对比表明,二者相对偏差在±20%以内,验证了该换热模型的准确性与适用性。通过进一步的研究发现：从换热管入口至出口,随着冷凝的进行,管内换热主要热阻由液膜热阻向气液界面的凝结热阻转变;主流气体对流换热过程基本可忽略。     

Investigations on landmine detection by BF3 detector

Experiments were carried out to investigate the possible use of neutron backscattering for the detection of polyethylene (PE) sample buried in the soil. In detection of landmine by neutrons, the neutron detector and its shield play an important role. In this paper, the effects of graphite, heavy water, polyethylene and boric acid moderators on the flux of back scattered neutrons were investigated. We have also experimentally verified the effect of BF3 detector shield and obtained good agreement with theory.     

Web Services interface of SSRF archive data analysis system

Accelerator database stores various static parameters and real-time data of accelerator. SSRF (Shanghai Synchrotron Radiation Facility) adopts relational database to save the data. We developed a data retrieval system based on XML Web Services for accessing the archive data. It includes a bottom layer interface and an interface applicable for accelerator physics. Client samples exemplifying how to consume the interface are given. The users can browse, retrieve and plot data by the client samples. Also, we give a method to test its stability. The test result and performance are described.     

Assessment of radioactivity levels in some oil samples from the western desert, Egypt

Distributions of natural gamma-emitting radionuclides were determined in 93 oil samples collected from some petroleum fields in the western desert of Egypt. The radioisotope activities in the area under investigation lay in the range of (21 ± 4) to (38 ± 13) Bq?L-1 for 226Ra, (9 ± 2) to (15 ± 5) Bq?L-1 for 232Th, and (154 ± 28) to (303 ± 54) Bq?L-1 for 40K. The mean values were 27, 12, and 201 Bq?L-1, respectively. Among oils, variations in radionuclide ac- tivities could be on account of differences in TDS, HCO3, and Ba, with high or low pH. In this environment, oil prop- erties differently affected the mobilization of natural radionuclides. The range of 226Ra variation had been compared with available data from other countries. The calculated absorbed dose rate ranged from 22.33 to 32.66 nGy?h-1 in lo- cation (B) and (E) respectively, which was less than the accepted value.     

Preparation and properties of 117m Sn(IV)-TTHMP in in-vitro and in small animals

In this work,TTHMP was synthesized and labelled with 117m Sn.The preparation conditions,stability and lipophilicity of 117m Sn(IV)-TTHMP were investigated.Biodistribution of the complex in rabbits and mice was studied.It was found that the quantity of TTHMP and pH value of the prepararion solution had vital effects on the labeling yield of 117m Sn(IV)-TTHMP.It was also found that 117m Sn(IV)-TTHMP was hydrophilic and stable at room temperature and 37℃ in open air 117m Sn(IV)-TTHMP showed unexpectedly high bone uptake and bone-to-blood ratio in the animals.This made it potentially useful as an reagent for skeletal scintigraphy and radiotherapy of bone tumors.     

Gamma radiation levels in the ambient environment of the QNPP Base

Monitoring results of gamma dose rate level in 1992～2004 in the ambient environment of the Qinshan Nuclear Power Plants(QNPP)Base,the northeast of Zhejiang Province,are reported in this paper.It is shown that the gamma dose rate of five monitoring sites of 2.5 km to QNPP Base is 84～113 nGy/h,with an average of 96 nGy/h in the 13 years.The average value is close to the background level of 93 nGy/h prior to operation of the QNPP Base,and is lower than the monitoring result of 101 nGy/h at the reference site in Hangzhou City.Within 50 km from the QNPP Base,the cumulative dose rate of the thermoluminescent dosimeter(TLD)is 90 nGy/h,which is lower than the back- ground level of 111 nGy/h.     

The role of AGFA high-energy CR in the calibration and quality control of multileaf collimators （MLC）

Linear accelerators equipped with multileaf collimators （MLC） are becoming more common and are widely used in the intensity-modulated radiotherapy （IMRT）. There is an imperative need to ensure the commissioning specification of the linear accelerators for the sake of quality assurance （QA） and quality control （QC）. This paper is aimed to investigate the role of AGFA high-energy CR （Computed Radiography） in calibrating dynamic multileaf collimators and evaluating the accuracy of the leaf position. The result shows that AGFA high-energy CR can easily and conveniently be used to calibrate MLC and verify its position. Hence, the application of AGFA high-energy CR is proved to be an accurate and time-saving method for routine MLC QC, especially when MLC calibration adjustments are required.