碘标记毒死蜱及其在小鼠体内的生物分布

为探讨¹³¹I标记毒死蜱（Chlorpyrifos, CPF）在小鼠体内的分布特点,采用Iodogen法对CPF进行¹³¹I标记,KM小鼠尾静脉注射¹³¹I-CPF（185 kBq/只,n=5）,分别于注射后5、10、30、60、120、240、1440 min取各脏器,计算每克组织摄取注射剂量的百分率（%ID/g）。结果显示,¹³¹I-CPF标记率达93.5%,放化纯度为96.9%,¹³¹I-CPF在小鼠体内广泛分布,主要经肺、胃、小肠、大肠、肌肉和颌下腺吸收,其放射性摄取率在注药后 10 min 时达高峰,分别为37.12%ID/g、6.18%ID/g、8.12%ID/g、8.15%ID/g、7.04%ID/g和7.02%ID/g;经肝和肾进行代谢,其放射性摄取率在5 min时分别为4.34%ID/g和8.50%ID/g, 4 h为0.22%ID/g和 0.69%ID/g。血液中放射性清除较快,放射性摄取率在注入后5 min时为37.27%ID/g,4 h为1.35%ID/g。碘标记CPF体外稳定,体内主要经肺和消化道吸收,肝、肾代谢,可用于进一步的微量示踪研究。     

13N-NH3*H2O的制备及生物分布研究

利用16O(p ,α) 13 N核反应 ,经戴氏合金 (Devarda’salloy)还原靶水制备出13 N -NH3 ·H2 O的生理盐水注射液。标记产物利用TLC、HPLC进行放射化学分析 ,放化纯度 >95 % ,放射性浓度为(1.11— 2 .2 2 )GBq/mL。小鼠分布实验显示心肌摄取率最高 ,平均 %ID/g为 19.5 4 % ;首次通过时 ,心肌和肺的摄取率最高 ,其 %ID/g各为 2 4 .90± 1.82和 2 2 .79± 1.94 ,约有 92 %的放射性从血液中清除 ;注射后 1min ,各器官中的放射性急剧下降 ,5min时下降到最低值 ,10min时各器官中的放射性又明显升高 ,在 1— 30min内 ,心脏摄取稳定在 11.34%— 2 9.2 4 %。13 N -NH3 ·H2 O有较高的心 /肝和心 /肺比值和较快的血液清除率。结果表明 ,Devarda’salloy还原法是一种简单快速、可获得较高核纯度和放化纯度的13 N -NH3 ·H2 O的制备方法。小鼠分布实验提示在静脉注射13 N-NH3 ·H2 O后 2— 5min内进行PET显像 ,可获得满意的图象。     

~(153)Sm-盐酸平阳霉素的标记及在小鼠体内的分布

研究了153Sm标记盐酸平阳霉素的条件以及标记物在荷S - 180肉瘤小鼠体内的分布情况。结果表明 :当pH为 5— 6,盐酸平阳霉素的量为 1mg时 ,加入适量放射源153SmCl3 溶液 ,室温反应30min可得到标记率 >98%的153Sm -盐酸平阳霉素溶液。室温下放置 72h后 ,放化纯度仍高达 97.2 %。向荷S - 180肉瘤小鼠的静脉中注入该标记物 ,分别在 3、6、12、2 4h处死 ,器官的放射性分布数据显示一定的肿瘤摄取和较高的骨摄取 ,最高分别可达 ( 1.615± 0 .2 19) %ID g和 ( 16.142± 3.50 1) %ID g ,瘤 血和骨 血最高可达 4 8和 90 8。     

碘标锰卟啉及其小鼠体内分布

通过131I标记锰卟啉(MnTBAP)探讨锰卟啉在小鼠体内的分布代谢。采用Iodogen法对锰卟啉进行131I标记;以聚酰胺薄膜为支持介质、生理盐水为展开剂,测定标记物的标记率和放化纯度;KM小鼠尾静脉注射131I-MnTBAP(每只185kBq,n=6),分别于注射后5、10、30、60、120、240、1 440min取各脏器,称重、测定计数率,计算每克组织摄取注射剂量的百分率(%ID/g)。结果表明,131I-MnTBAP标记率达96.3%,其放化纯在标记后2、24、48h分别为96%、95%、94.5%;动物实验显示131I-MnTBAP在小鼠体内广泛分布,主要经肝和肾脏进行代谢,肝、肾的放射性摄取在注入后5min时分别为8.34%ID/g、12.23%ID/g,4h时则分别下降为0.34%ID/g、0.73%ID/g,血液中放射性清除较快,注入后5min时血液中放射性摄取为5.55%ID/g,4h为0.86%ID/g。因此,碘标记锰卟啉的标记物体外稳定,体内主要经肝、肾代谢,可用于进一步的微量示踪研究。     

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。     

~(99)Tc~m-DTPA-Gd的制备及其生物学分布

应用99Tcm标记顺磁对比剂Gd-DTPA并研究其生物学分布特性。99Tcm在氯化亚锡还原下一步法标记Gd-DTPA,采用薄层纸层析法(TLC)分析标记率大于98%,室温放置6 h内放化纯稳定。三氯乙酸沉淀法测得99Tcm-DTPA-Gd在家兔血浆中的蛋白结合率为(3.80±0.25)%。正常昆明小鼠体内分布实验显示,注射99Tcm-DTPA-Gd后1 min血液的放射性摄取为(14.79±9.77)%ID/g,肾脏的摄取为(26.02±8.50)%ID/g;心、肝、脾和肺有少量分布,脑组织分布最少(1%ID/g);注射99Tcm-DTPA-Gd 30～60 min后多数脏器的滞留小于1%ID/g。正常成年家兔注射99Tcm-DTPA-Gd后采用肾动态显像模式观察60 min内的分布和排泄,显示99Tcm-DTPA-Gd主要经肾脏排泄,摄取高峰时间约为5～10 min,半排时间约为10～20 min,其它脏器无特异性滞留。     

99Tcm标记NGR及其在荷人HePG2肝癌裸鼠体内的生物分布及SPECT显像

用⁹⁹Tc^m标记了含有天冬酰胺-甘氨酸-精氨酸（Asn-Gly-Arg）序列的血管靶向性短肽NGR,评价了标记物⁹⁹Tc^m-NGR的放化性质以及在荷HePG2肝癌模型裸鼠体内的生物分布和SPECT显像。标记结果显示,⁹⁹Tc^m-NGR的标记率>90%,放化纯度>95%。荷瘤裸鼠体内生物分布结果显示,⁹⁹Tc^m-NGR在肾脏和肝脏的摄取率较高,注射后1 h肿瘤摄取达（2.52±0.62）%ID/g,最高达（7.26±2.71）%ID/g,12 h仍然达（3.93±1.93）%ID/g,但在竞争性抑制组中摄取率为（1.29±0.85）%ID/g。荷瘤裸鼠的SPECT显像结果显示,除肿瘤外,其他组织器官的放射性摄取随时间延长逐渐降低,肿瘤与肌肉组织的放射性攝取比（T/NT）4 h时最高,可达3.25。注射后1 h肿瘤可见,12 h时最为清晰。以上结果提示,⁹⁹Tc^m-NGR易于制备,具有良好的靶向性, 在肿瘤的诊疗中具有良好的研究前景。     

碘标APRPGY多肽与肿瘤新生血管亲和性的实验研究

探讨放射性碘标记APRPGY肽在体内与肿瘤新生血管的亲和特性.氯胺-T法对APRPGY肽行碘-131标记,并分析标记物放化纯;ICR小鼠创伤愈合模型和Hep A实体瘤模型小鼠尾静脉注射131I-APRPGY(174kBq/只),并于不同时间断颈处死小鼠,取各脏器或组织,称重,测cpm,计算%ID/g等(n=6).标记物放化纯为95.5%,并在24h内保持基本稳定;动物体内分布显示,131I-APRPGY在血、肾中分布较多,且组织清除速度较快,主要以肾脏排泄;肿瘤组织中的131I-APRPGY在注射后10 min达6.7%ID/g,至240 min时降为2.1%ID/g,在5、10、30、60、120、240min时分别为肌肉的2.1、6.2、4.7、3.3、3.5、3.2倍;131I-APRPGY的创伤愈合组织与肌肉的放射性比在10、30、60、120和240min时分别为0.8、1.3、1.8、1.9和1.4.131I-APRPGY能较好地浓聚于实体瘤组织,在创伤愈合组织中也相对浓聚,证实131Ⅰ-APRPGY与肿瘤新生血管有较强的亲和性,经进一步修饰,有可能获得靶向肿瘤新生血管的显像药物.     

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。     

125I-RC-160的标记方法研究及其正常小鼠体内的分布特征

研究了一种高效碘标多肽RC - 16 0的方法 ,在其中以溴代琥珀酰亚胺 (NBS)为氧化剂 ,常规氯胺T法作为对照。对12 5I -RC - 16 0的标记率、比活度进行了评价 ,并观察12 5I -RC - 16 0在正常小鼠体内的生物分布特征。结果显示 :在丙酮:生理盐水 =1:1体系中 ,测得12 5I -RC - 16 0的标记率NBS法为 92 %,比活度为 1.95× 10 12 Bq/mmoL ,标记率随NBS用量增加而增高 ,最佳用量比为RC - 16 0 (μg):12 5I(MBq):NBS(μg) =3:7.4:1,且产物无需纯化 ;Ch -T法标记率为5 6 %,比活度为 0 .6 5× 10 12 Bq/mmoL ,经SepPaK -C18反向色谱柱纯化 ,12 5I -RC - 16 0的标记率可达 92 %。标记物在血中清除较快 ,注射后不到 1h血中的放射性就下降了 87.2 %;12 5I -RC -16 0在甲状腺及肾的浓集度很低 ,主要经过消化系统排出体外。     

Identification of radiation treatment of wheat （Triticum aestivum. L）and rice （Oryza sativa. L） samples using thermoluminescence of contaminating minerals

Food irradiation is gaining popularity worldwide and this technology is important to improve quality and reduce the post harvest losses of food. Because of the rapid commercialization of irradiated foods throughout the world, compliance of different regulations relating to use of technology in different countries and demand of consumers for clear labelling of irradiated foods, there is need for the development of analytical methods to detect radiation treatment of food. Among several methods studied so far, thermoluminescence （TL） is an important method that can be used to find out the irradiation history of food that contain even a very minute amount of dust particles. In this study, the irradiated and unirradiated wheat and rice samples were analyzed using the TL method. The samples were purchased from the local market of Peshawar and irradiated to radiation doses of 0.5 and 1.0 kGy using Co-60 gamma irradiator at the Nuclear Institute for Food and Agriculture （NIFA）, Peshawar. The mineral contaminants were isolated by jet water, ultrasonic treatment, and density gradient. TL glow curves of the isolated minerals from irradiated and unirradiated samples were recorded between the temperature ranges of 50-500℃ using a TL reader. Generally, the glow curves for irradiated samples showed much higher TL intensities （TL1） than the unirradiated samples. The results were normalized by rerradiation of mineral samples to gamma-ray dose of 1.0 kGy followed by determination of the second glow curves （TL2）. The ratio of the area of first glow curve to that of second glow curve （TL1/TL2） was calculated for selected temperature intervals and compared with the recommended values for unirradiated and irradiated samples. Finally, the shapes of the glow curves for irradiated and unirradiated samples were also analyzed. On the basis of these results （comparison of TL-intensities, TL1/TL2 ratios and shapes of the glow curves）, all the irradiated and unirradiated samples of wheat and rice were unequivocally identified.     

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.     

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。     

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.     

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.     

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.     

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.     

The preclinical pharmacological study of dopamine transporter imaging agent 18F-FP-β-CIT

The paper is to study pharmacologic characteristics of 18F-FP-β-CIT (18F-N-(3-fluoropropyl)-2β- carbomethoxy-3β- (4-iodophenyl)nortropane) as an imaging agent for dopamine transporter. The radiochemical purity of 18F-FP-β-CIT in aqueous solution was over 95% after standing at room temperature for 4h. Biodistribution displayed rapid uptake in rat brain (1.375 %ID/organ at 5min and 0.100 %ID/organ at 180 min) and the striatal uptake was 1.444,0.731, 0.397, 0.230 and 0.146 %ID/g at 5, 30, 60, 120 and 180 min, respectively. The values of striatum/cerebellum,striatum/frontal cortex and striatum / hippocampus in rat's brain at 30 min were 3.38, 2.17 and 2.40 respectively. The uptake in striatum can be blocked by β-CFT, suggesting that 18F-FP-β-CIT binds to DAT peculiarly. The compound was rapidly cleared from monkey's blood. The striatal uptake was bilaterally decreased in the left-sided lesioned PD rats, compared with normal control. Brain PET imaging studies in normal monkey showed that 18F-FP-β-CIT was concentrated in striatum. The test of undue toxicity showed that the dose received by mice was 1250 times as by human, which indicates that 18F-FP-β-CIT is very safe. So 18F-FP-β-CIT is a promising PET imaging agent for DAT with safety and validity.     

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.