~（99m）Tc标记DTPA-生物素和hIgG在正常小鼠体内分布实验

目的：探讨DTPA-生物素和hIgG的99mTc标记方法,并观察标记物在体内、外的稳定性及其在正常小鼠体内分布。方法：99mTc标记DTPA-生物素采用直接标记法,99mTc标记hIgG采用2-巯基乙醇还原法,标记率及放化纯测定采用纸层析法,并分别观察99mTc-生物素和99mTc-IgG在生理盐水（NS）中的稳定性;取24只正常小鼠,分为两组,分别经尾静脉注入99mTc-生物素和99mTc-hIgG,注入剂量为7.4MBq/100μl,于注入后1h、3h、6h、12h行SPECT显像并处死小鼠分离各脏器,测量放射性计数,计算各脏器每g组织百分注射剂量（%ID/g）。结果：99mTc标记DTPA-生物素的标记率〉80%,99mTc标记hIgG的标记率〉70%,99mTc-hIgG的放化纯〉90%;在NS中温育12h未观察到99mTc-生物素和hIgG放化纯度明显降低;体内生物分布显示99mTc-生物素肾内摄取高,主要经泌尿系统排泄;99mTc-hIgG在体内主要分布于肝、脾、肾,且在血液中存留时间较长。结论：99mTc标记DTPA-生物素和hIgG具有良好的标记率及体外稳定性,小鼠体内分布实验表明,99mTc-生物素和99mTc-hIgG体内分布的明显不同,为下一步基于亲和素-生物素系统预定位技术各组分的应用提供实验依据。     

结肠癌荷瘤裸鼠三步法预定位放免显像及导向治疗研究

目的:探讨亲和素-生物素系统在人结肠癌裸鼠模型中进行预定位放免显像及导向治疗的实验研究。方法:应用三步法给药,在注药后4～48h对荷人结肠癌进行ECT显像和体内分布测定。预定位治疗组采用单次较大剂量投入治疗(放射性剂量为11.1MBq),治疗前后定期测量裸鼠的体重和肿瘤生长体积以及瘤块的组织病理学检查。结果:三步法组在注药后4h肿瘤即显像,其瘤/血比值为5.76±1.64明显高于对照组(直接标记法组和153Sm-DB2组分别为0.26±0.08和1.01±0.22)。三步法预定位治疗组与直接标记单抗组均能明显抑制荷瘤裸鼠体内人结肠癌的生长。结论:三步法预定位具有显著改善血T/NT比值,肿瘤显像时间提前的特点;预定位治疗具有明显的肿瘤抑制效应。     

^99mTc—HL9l肿瘤乏氧显像的动物实验

目的　用99mTc -HL91乏氧显像剂对肺腺癌小鼠模型进行体内分布和显像实验 ,以探索其对肿瘤显像的适用性 .方法　99mTc -HL91一步法标记 ,放化纯 >95 % .对 15只肺腺癌动物模型腹腔注射99mTc -HL9118 5MBq ,于 1～ 2 4小时处死取血液、肿瘤、脑、肺、心、肝、脾、肾、骨等标本称重 ,测定放射性计数 ,计算ID % /g及肿瘤组织与非肿瘤组织放射性比值 (T/NT) .同时在腹腔注射99mTc-HL91后于不同时间对模型进行静态显像 .结果　肿瘤组织对99mTc-HL91有较早较高的摄取和滞留 ,T/NT比值随时间延长而有增高趋势 .显像示肿瘤组织有较好的放射性浓聚 ,图像清晰 ,对比度良好 .结论　99mTc-HL91标记简单 ,标记率高 ,使用方便 ,在肿瘤组织中有较好的摄取与滞留 ,是一种良好的肿瘤乏氧显像剂 ,但需要进一步研究其机理和改进方法 ,提高T/NT比值 ,以开展临床试验     

99mTc(V)-DMSA骨显像诊断细菌性骨关节炎动物模型实验研究

目的利用骨关节炎症动物模型观察99mTc(V)-DMSA的生物分布和在骨关节炎症区域的代谢特点.方法在制作骨关节炎症动物模型的基础上,经在体显像及其感兴趣区技术计算器官和炎症关节的放射性活度的变化,同时也利用动物模型离体的测量器官或组织的百分注射量,分析99mTc(V)-DMSA在各器官和骨关节炎症区域的代谢特点.结果骨关节炎症区域对99mTc(V)-DMSA有较高的摄取,骨关节炎症的患/健比值高峰出现在注射示踪剂后的2小时～6小时之间:百分注射量靶/非靶比值分别为2.353±0.465和3.196±0.461(%ID/g);在体显像患/健比值分别为2.593±0.343和2.882±0.525(%).99mTc(V)-DMSA主要经泌尿系统排出,其在肠道系统有聚集并不影响四肢骨病灶的观察.结论 99mTc(V)-DMSA有较低和较稳定的蛋白结合率,是急性骨关节炎症良好的显像剂,其最佳显像时间为在注射99mTc(V)-DMSA后的2～3小时之间.     

99m Tc 标记单克隆抗体Au14-1对荷宫颈癌小鼠的放射免疫显像研究

目的和方法：应用99mTc直接法标记抗小鼠宫颈癌（U14）单克隆抗体Au14-1,对荷瘤Km小鼠进行放射性分布和放射免疫显像的实验观察,探讨用99mTc－An14-1作宫颈癌导向诊断和导向治疗的可能性。结果：（1）99mTc－Au14-1注射后12h肿瘤灶已有放射性聚集,24h肿瘤组织的％ID／g值达8．79,呈明显特异性浓聚;（2）除肾脏外,各脏器的T／NT值在2．02~6．71之间,SPECT图像12h已见肿瘤显影,24h肿瘤影像更为清晰。结论：99TcTc－An14-1的体内分布与显像结果相一致,表明An14-1在体内具有良好的宫颈癌导向定位作用。     

^99mTc（V）-DMSA骨显像诊断细菌性骨关节炎动物模型实验研究

目的　利用骨关节炎症动物模型观察99mTc(V) -DMSA的生物分布和在骨关节炎症区域的代谢特点 .方法　在制作骨关节炎症动物模型的基础上 ,经在体显像及其感兴趣区技术计算器官和炎症关节的放射性活度的变化 ,同时也利用动物模型离体的测量器官或组织的百分注射量 ,分析99mTc(V) -DMSA在各器官和骨关节炎症区域的代谢特点 .结果　骨关节炎症区域对99mTc(V) -DMSA有较高的摄取 ,骨关节炎症的患 /健比值高峰出现在注射示踪剂后的 2小时～ 6小时之间 :百分注射量靶 /非靶比值分别为 2 .35 3± 0 .4 6 5和 3.196± 0 .4 6 1( %ID/g) ;在体显像患 /健比值分别为 2 .5 93± 0 .343和 2 .882± 0 .5 2 5 ( % ) .99mTc(V) -DMSA主要经泌尿系统排出 ,其在肠道系统有聚集并不影响四肢骨病灶的观察 .结论　99mTc(V) -DMSA有较低和较稳定的蛋白结合率 ,是急性骨关节炎症良好的显像剂 ,其最佳显像时间为在注射99mTc(V) -DMSA后的 2～ 3小时之间     

~(99)Tc~m-SZ-21兔动脉血栓模型放射免疫显像研究

目的:探讨99mTc标记抗血小板板膜单克隆抗体SZ-21在兔股动脉血栓模型放免显像中的应用价值。方法:将抗体用2-IT法修饰后进行99Tcm标记;5只血栓模型兔耳缘静脉注射99Tcm-SZ-21后进行SPECT平面显像,观察血栓部位放射性分布并勾划感兴趣区(ROI),计算血栓与周围肌肉(T/M)和血栓与对侧血管(T/B)ROI比值。1只模型兔注射99Tcm-GH,作为阴性对照。结果:注射99Tcm-SZ-21后30分钟,血栓开始显影,至注射后2小时,血栓影像清晰;血栓模型活体显像时T/M和T/B比值分别为2.55±0.72和1.94±0.51,离体显像时T/B比值为4.43±1.5。结论:99Tcm-SZ-21与新鲜血栓具有较好的结合能力,靶与非靶组织比值高,能够对血栓进行早期、快速地成像。     

骨关节炎动物模型对^99mTc—枸橼酸摄取及其分布的研究

目的　利用骨关节炎症动物模型观察99mTc -枸橼酸的生物分布和在骨关节炎症区域的代谢特点 .方法　在制作骨关节炎症动物模型的基础上 ,经在体显像及其感兴趣区技术计算器官和炎症关节的放射性活度的变化 ,同时也利用动物模型离体的测量器官或组织的百分注射量 ,分析99mTc -枸橼酸在各器官和骨关节炎症区域的代谢特点 .结果　99mTc -枸橼酸的蛋白结合率为 17.0 1± 0 .75 % ,骨关节炎症区域对99mTc -枸橼酸有较高的摄取 ,骨关节炎症的患 /健比值出现在注射示踪剂后的 30分钟到 1小时之间 :在体显像患 /健比值分别为 4.12 0± 0 .5 5 2和 3.15 0± 0 .5 87;百分注射量靶 /非靶比值分别为 3.2 79± 0 .46 3和 3.899± 0 .12 5 .99mTc -枸橼酸主要经泌尿系统排出 ,少量经肝脏 -肠道系统排出 .结论　99mTc -枸橼酸有较低的蛋白结合率 ,是急性骨关节炎症良好的显像剂 ,其最佳显像时间为注射99mTc-枸橼酸后的 1小时     

^99mTc-CPF制备及实验研究

目的 探讨炎症显像剂^99mTc-环丙沙星（^99mTc-CPF）在小鼠体内分布的特点，评价其作为新型炎症显像剂的价值。方法 制备^99mTc-CPF，并测定其放化纯度和标记率。制作小白鼠炎症模型。并经尾静脉注入0．1ml ^99mTc-CPF，分别于0．5、1、4、6、12h处死小白鼠，取血样和部分器官组织。测量其放射性。结果 ^99mTc-CPE标记率〉90％。室温下6h内化合物的放化纯稳定。小白鼠炎症组织与正常组织的放射性比值高，注射后1、4、6、12h，炎症组织与对侧正常组织比值分别为3．48、4．30、4．17、4．16．^99mTc-CPF主要由肝脏代谢、经肾脏排泄。血液清除较快。结论 ^99mTc-CPE是一种灵敏度高的炎症灶显像剂。且制备方法简单、方便。     

亲和素-生物素系统预定位技术在炎症显像中的应用

亲和素-生物素系统预定位技术已在肿瘤放射免疫显像中得到成功应用.近年来,这一新技术也已开始用于炎症的显像研究中.本文就亲和素-生物素系统预定位技术及其在炎症动物模型中的实验研究和临床试用研究中的情况进行简要综述.并就目前炎症显像的现状及存在的问题,以及预定位炎症显像的应用前景加以讨论.     

Tracer-cocktail injections for combined pre- and intraoperative multimodal imaging of lymph nodes in a spontaneous mouse prostate tumor model

To improve surgical guidance toward prostate draining lymph nodes, we investigate the potential of intraoperative fluorescence imaging and combined pre- and intraoperative multimodality imaging approaches. Transgenic adenocarcinoma mouse prostate mice with spontaneous prostate tumors are injected intratumorally with: 1. a cocktail of patent blue (Pb) and indocyanine green (ICG); 2. a cocktail of albumin radiocolloids (99mTc-NanoColl), Pb, and ICG; or 3. a cocktail of radiolabeled albumin (99mTc-Vasculosis), Pb, and ICG. The distribution of these imaging agents over the lymph nodes (LNs) are studied at different time points after injection. We find that at 60-min postinjection, ICG significantly improves the detection of the LNs compared to Pb, 53 versus 7%, respectively. Moreover, a cocktail of ICG and 99mTc-NanoColl improves the fluorescent detection rate to 86%, equalling that of the clinically applied 99mTc-NanoColl. A similar overlap is observed in our initial clinical pilot data. Fluorescent detection of the LNs using a ICG with 99mTc-Vasculosis gives similar results as "free" ICG (58%; 60 min). A 99mTc-NanoColl, Pb, and cocktail ICG enriches the standard 99mTc-NanoColl approach by adding optical detection of the sentinel lymph nodes. Furthermore, this approach improves fluorescent-based guidance and enables both accurate surgical planning and intraoperative detection, based on a single injection.     

低表达mCD99L2 鼠B淋巴瘤细胞亚系的建立及鉴定

目的： 建立和鉴定稳定的低表达mCD99L2鼠B淋巴瘤细胞亚系，以探究mCD99L2基因在Hodgkin′s淋巴瘤 H/RS细胞形成中的作用。方法: 对前期构建的慢病毒质粒稳定干扰的A20-LV-mCD99L2 克隆株进行体外培养，分别选择第10、20、30、40代细胞，DNA-PCR检测shRNA干扰载体的整合，RT-PCR及荧光定量PCR检测目的基因mCD99L2的表达水平，倒置显微镜观察A20-LV-mCD99L2细胞的形态变化并进行计数，免疫荧光观察H/RS样大细胞 mCD30分子的表达。结果: 第10、20、30、40代A20-LV-mCD99L2细胞(1) 抽提DNA进行PCR均能检测出shRNA干扰载体稳定整合至A20细胞基因组；(2) RT-PCR及荧光定量PCR检测目的基因mCD99L2均较A20细胞呈低水平表达；(3) 各代A20-LV-mCD99L2细胞中均发现有类似人H/RS细胞的大细胞(A20-H/RS)；(4) 免疫荧光检测H/RS样细胞mCD30 呈阳性表达。结论: 鉴定和建立了低表达mCD99L2基因的A20细胞亚系，该细胞亚系中存在类似人H/RS细胞的大细胞。     

Rodent brain imaging with SPECT/CT

We evaluated methods of imaging rat models of stroke in vivo using a single photon emission computed tomography (SPECT) system dedicated to small animal imaging (X-SPECT, Gamma Medica-Ideas, Northridge, CA). An animal model of ischemic stroke was developed for in vivo SPECT/CT imaging using the middle cerebral artery occlusion (MCAO) technique. The presence of cerebral ischemia was verified in ex vivo studies using triphenyltetrazolium chloride (TTC) staining. In vivo radionuclide imaging of cerebral blood flow was performed in rats following MCAO using dynamic planar imaging of 99mTc-exametazime with parallel hole collimation. This was followed immediately by in vivo radionuclide imaging of cerebral blood flow with 99mTc-exametazime in the same animals using 1-mm pinhole SPECT. Correlated computed tomography imaging was performed to localize radiopharmaceutical uptake. The animals were allowed to recover and ex vivo autoradiography was performed with separate administration of 99mTc-exametazime. Time activity curve of 99mTc-exametazime showed that the radiopharmaceutical uptake could be maintained for over 9 min. The activity would be expected to be relatively stable for a much longer period, although the data were only obtained for 9 min. TTC staining revealed sizable infarcts by visual observation of inexistence of TTC stain in infracted tissues of MCAO rat brains. In vivo SPECT imaging showed cerebral blood flow deficit in the MCAO model, and the in vivo imaging result was confirmed with ex vivo autoradiography. We have demonstrated a capability of imaging regions of cerebral blood flow deficit in MCAO rat brains in vivo using a pinhole SPECT dedicated to small animal imaging.     

Optical imaging of Tc-99m-based tracers: in vitro and in vivo results

It has been recently shown that optical imaging (OI) methods can be used to image the in vivo biodistribution of several radiopharmaceuticals labeled with beta or alpha emitters. In this work particular attention has been focused on investigating the weaker optical signal induced by an almost pure gamma emitter like Tc-99m. Visible light emission measurements of a water solution containing Tc-99m were performed using a small animal OI system. A sequence of images was acquired for 24 h in order to study the decay of the luminescence signal. The difference between the luminescence decay half life and well-known Tc-99m half life was equal to 1%. in vivo imaging was performed by injecting one control nude mice with Tc-99m-MDP. Optical images obtained with equipment designed for bioluminescence imaging showed that a visible light emission was distinguishable and correctly localized in the bladder region where a higher concentration of Tc-99m-MDP was expected. The bladder to background ratio was always greater than 1. We conclude that the experimental data presented in this paper show that it is possible to detect in vivo luminescence optical photons induced by Tc-99m. This is important especially considering the large number of Tc-99m-based radiopharmaceutical currently available.     

99Tcm-MIBI亲肿瘤显像对甲状腺结节的诊断价值

目的:探讨99Tcm-甲氧基异丁基异睛（99Tcm-MIBI）甲状腺亲肿瘤显像对甲状腺结节良恶性的鉴别诊断价值。方法:回顾性分析165例经超声诊断为甲状腺结节,且接受手术治疗获得病理诊断的患者,所有患者先进行99TcmO4-甲状腺显像,依据图像判断“冷结节”或“凉结节”,次日进行99Tcm-MIBI甲状腺亲肿瘤显像,包括早期显像和延迟显像。以早期显像或/和延迟显像原“冷/凉结节”部位出现异常摄取,判断为阳性。并以ROI技术测定结节部位99Tcm-MIBI的摄取T/N比值。对甲状腺癌结节按长径分组,计算各组的显像阳性率。以病理结果为标准,计算99Tcm-MIBI显像检查的灵敏度、特异性、阳性预测值、阴性预测值和准确度,甲状腺癌组早期显像和延迟显像之间T/N比值的比较、甲状腺癌和甲状腺良性结节之间早期显像和延迟显像T/N比值的比较,采用t检验。不同结节大小组别之间显像阳性率的比较,采用Chi-Square检验。结果:165例患者,手术后病理证实甲状腺癌97例,甲状腺良性病变68例,99Tcm-MIBI显像对甲状腺结节的诊断灵敏度为84.5%（82/97）,特异性为76.4%（52/68）,阳性预测值为83.6%（82）,阴性预测值为77.6%（52）,准确度为81.2%（134/165）。在甲状腺癌,早期显像结节T/N比值（t=2.706 6, P<0.005）以及延迟显像T/N比值（t=2.398 1, P<0.01）,均显著高于甲状腺良性病变组。甲状腺癌结节长径≥20 mm组阳性检出率74.1%,≥30 mm组为91.6%,长径≥30 mm组和20~29 mm组比较,阳性检出率未见显著性差异（[χ2]=3.575 9, P>0.05）,但20~29 mm组比10~19 mm组（[χ2]=3.857 1, P<0.05）以及<10 mm组（[χ2]=8.851 7, P<0.01）阳性检出率明显提高。结论:99Tcm-MIBI甲状腺亲肿瘤显像,对甲状腺结节具有较好的诊断价值,与甲状腺良性病变比较,甲状腺癌对99Tcm-MIBI的摄取更多。当甲状腺癌结节长径大于20 mm,诊断阳性率高,结节大小是影响甲状腺癌诊断灵敏度的重要因素。     

A three-dimensional model-based partial volume correction strategy for gated cardiac mouse PET imaging

Quantification in cardiac mouse positron emission tomography (PET) imaging is limited by the imaging spatial resolution. Spillover of left ventricle (LV) myocardial activity into adjacent organs results in partial volume (PV) losses leading to underestimation of myocardial activity. A PV correction method was developed to restore accuracy of the activity distribution for FDG mouse imaging. The PV correction model was based on convolving an LV image estimate with a 3D point spread function. The LV model was described regionally by a five-parameter profile including myocardial, background and blood activities which were separated into three compartments by the endocardial radius and myocardium wall thickness. The PV correction was tested with digital simulations and a physical 3D mouse LV phantom. In vivo cardiac FDG mouse PET imaging was also performed. Following imaging, the mice were sacrificed and the tracer biodistribution in the LV and liver tissue was measured using a gamma-counter. The PV correction algorithm improved recovery from 50% to within 5% of the truth for the simulated and measured phantom data and image uniformity by 5-13%. The PV correction algorithm improved the mean myocardial LV recovery from 0.56 (0.54) to 1.13 (1.10) without (with) scatter and attenuation corrections. The mean image uniformity was improved from 26% (26%) to 17% (16%) without (with) scatter and attenuation corrections applied. Scatter and attenuation corrections were not observed to significantly impact PV-corrected myocardial recovery or image uniformity. Image-based PV correction algorithm can increase the accuracy of PET image activity and improve the uniformity of the activity distribution in normal mice. The algorithm may be applied using different tracers, in transgenic models that affect myocardial uptake, or in different species provided there is sufficient image quality and similar contrast between the myocardium and surrounding structures.     

^99mTc—NOEt心肌显像的最佳显像时间的研究

目的:研究~(99m)Tc-NOEt(NOEt:N—乙氧基—N—乙基氨荒酸钠)的最佳负荷显像时间及再分布显像时间,方法:32例CAD患者及8例正常对照者进行~(99m)Tc-NOEt动态心肌断层SPECT显像研究,分析心肌显像质量及心肌显像结果 结果:~(99m)Tc-NOEt心肌显像质量随时间的递增而明显改善,但再分布显像时间过长反而造成部分心肌显像质量下降;~(99m)Tc-NOEt再分布现象可能发生较早.结论:建议负荷心肌显像时间直在15分钟进行,再分布显像在2小时进行,最好不超过4小时.     

小鼠胚胎干细胞表面糖分子被凝集素特异性识别的研究

目的　探讨小鼠胚胎干细胞表面糖蛋白能够被特异性识别的凝集素。 方法　通过磁珠筛选出小鼠胚胎干细胞系ES-D3 和 ESC57BL/6中周期特异性胚胎抗原1(stage specific embryonic antigen-1,SSEA-1)阳性的胚胎干细胞，进行凝集素的特异性结合，流式细胞仪筛选和免疫荧光染色，观察凝集素特异性结合情况。 结果　磁珠法可以筛选出99%的SSEA-1阳性细胞，它们代表着未分化的胚胎干细胞。在SSEA-1阳性细胞中，凝集素的结合实验的流式筛选提示，凝集素DSL结合率达99%，多花紫藤凝集素(Wisteria Floribunda Lectin,WFL)的结合呈双相性，部分不结合，部分高度结合；而荆豆凝集素I( Ulex europaeus Agglutinin UEAI)几乎不结合。 结论　曼陀罗植物凝集素(Datura stramonium Lectin,DSL)可以象SSEA-1一样，作为小鼠胚胎干细胞的特异性标志物，而UEAI可以作为阴性标志物。     

99Tcm-MIBI SPECT/CT同机融合显像对颅内占位病变的临床应用价值

近年来,随着SPECT/CT融合显像的发展,^99Tc^m-MIBI作为一种应用广泛的亲肿瘤显像剂在颅内占位病变的应用价值变得越来越高.本文介绍了^99Tc^m-MIBI的显像机制,阐述了^99Tc^m-MIBI SPECT/CT同机融合显像对颅内占位病变的临床应用价值,并与多模态影像技术进行了分析与比较.