^99mTc标记的抗心肌肌钙蛋白Ⅰ单克隆抗体在心肌损伤大鼠体内的分布

目的研究^99mTc标记的抗心肌肌钙蛋白Ⅰ单克隆抗体（AcTnIMA）在实验性心肌损伤大鼠体内的分布，探讨^99mTc-AcTnIMA是否可以作为心脏放射免疫显像剂。方法第一批大鼠实验组：20只急性心肌损伤大鼠注射^99mTc-AcTnIMA0．2mci，分别于注射后2、4、6、8h处死（每次5只），取血液、肝、脾、肾、正常肌肉、肺、心脏，计算每克组织计数占总注入计数的百分比（ID％／g）及心-肺ID％／g比（HLR）；药物对照组：20只急性心肌损伤大鼠注射^99mTc标记的非特异性免疫球蛋白（N-IgG）0．2mci，处死方法同实验组。取肺及心脏，计算ID％／g及HLR；空白对照组：20只正常大鼠注射^99mTc-AcTnIMA0．2mci，处理方法同药物对照组。第二批50只心肌损伤大鼠分别于发生心肌损伤后2、4、6、8、12、24h，3、5、10、15d分10次静脉注射^99mTc-AcTnIMA0．2mci（每次5只），注射后4h处死，计算出ID％／g及HLR。结果损伤心肌摄取^99mTc-AcTnIMA为特异性摄取，摄取的高峰时间为4h；损伤心肌摄取^99mTc-AcTnIMA与损伤发生时间无关。结论^99mTc-AcTnIMA有望作为心脏放射免疫显像剂诊断心肌损伤。     

99mTc标记的抗心肌肌钙蛋白I单克隆抗体在心肌损伤大鼠体内的分布

目的 研究99mTc标记的抗心肌肌钙蛋白I单克隆抗体(AcTnIMA)在实验性心肌损伤大鼠体内的分布,探讨99mTc-AcTnIMA是否可以作为心脏放射免疫显像剂.方法 第一批大鼠实验组:20只急性心肌损伤大鼠注射99mTc-AcTnIMA 0.2mci,分别于注射后2、4、6、8h处死(每次5只),取血液、肝、脾、肾、正常肌肉、肺、心脏,计算每克组织计数占总注入计数的百分比(ID%/g)及心-肺ID%/g比(HLR);药物对照组:20只急性心肌损伤大鼠注射99mTc标记的非特异性免疫球蛋白(N-IgG)0.2mci,处死方法同实验组.取肺及心脏,计算ID%/g及HLR;空白对照组:20只正常大鼠注射99mTc-AcTnIMA 0.2mci,处理方法同药物对照组.第二批50只心肌损伤大鼠分别于发生心肌损伤后2、4、6、8、12、24h,3、5、10、15d分10次静脉注射99mTc-AcTnIMA 0.2mci(每次5只),注射后4h处死,计算出ID%/g及HLR.结果 损伤心肌摄取99mTc-AcTnIMA为特异性摄取,摄取的高峰时间为4h;损伤心肌摄取99mTc-AcTnIMA与损伤发生时间无关.结论 99mTc-AcTnIMA有望作为心脏放射免疫显像剂诊断心肌损伤.     

心脏肌钙蛋白Ⅰ与抗心肌抗体对类风湿关节炎的临床意义

目的:探讨心脏肌钙蛋白Ⅰ(cTnI)与抗心肌抗体(AHA)对类风湿关节炎的诊断价值。方法:选择27例类风湿性关节炎(RA)患儿应用酶联免疫吸附试验法对其血清进行cTnI与AHA的测定,并同时检测肌酸激酶同工酶(CK-MB)。结果:27例幼年性RA患儿中12例cTnI阳性,16例AHA阳性,正常对照组cTnI,AHA,CK-MB全部阴性,且AHA阳性组cTnI,CK-MB值明显高于AHA阴性组。结论:RA患儿cTnI,AHA敏感性高于CK-MB,且AHA阳性组心血管受累的可能性大,从而提示cTnI,AHA对RA患儿心脏受累及早期给予保护措施,具有重要的指导意义。     

人心肌肌钙蛋白Ⅰ单克隆抗体的制备与鉴定

为了建立抗人心肌肌钙蛋白Ⅰ(CTnI)单克隆抗体(McAb)的杂交瘤细胞株。以重组表达并纯化后的CTnI免疫BalB/C小鼠,采用传统单克隆抗体技术筛选能稳定分泌抗CTnI McAb的杂交瘤细胞株。结果:建立了3株稳定分泌抗CTnI McAb的杂交瘤细胞株2E3,3D4和3E6,腹水效价分别为4×10-5,1×10-6,1×10-5,亲和常数分别为4.8×108,5.2×109,3.6×108,最低检测浓度分别为20,40,20μg/L,其中2E3和3D4可以识别CTnI的不同表位。     

小儿重症肺炎心肌肌钙蛋白Ⅰ测定分析

目的探讨心肌肌钙蛋白Ⅰ（cTnⅠ）在小儿重症肺炎合并心肌损害中的意义。方法对48例重症肺炎小儿与18例轻症肺炎小儿进行cTnⅠ及肌酸磷酸激酶（CK—MB）测定。结果重症肺炎组cTnⅠ阳性率明显高于CK-MB。合并先天性心脏病重症肺炎组cTnⅠ测定值与无先天性心脏病重症肺炎组相比,差异有显著性（P〈0．05）。结论cTnⅠ可作为评价小儿重症肺炎心肌损害的指标。重症肺炎若无先天性心脏病心肌损害常呈一过性,而合并先天性心脏病时心肌损害程度重,且cTnⅠ异常持续时间长。     

心肌肌钙蛋白Ⅰ对毒鼠强中毒心肌损伤的诊断价值

目的 探讨心肌肌钙蛋白Ⅰ（cTNⅠ）对毒鼠强中毒患者心肌损伤的诊断价值。方法 应用荧光免疫法对36例毒鼠强中毒患者进行血清cTNⅠ、肌酸激酶同工酶CK-MB检测。结果 发病后3h cTNⅠ阳性率55．5％，CK-MB阳性率19．4％；中毒后72h cTNⅠ阳性率80．5％，CK—MB阳性率22．2％。cTNⅠ阳性率高于CK-MB（P〈0．05）。结论 毒鼠强中毒患者存在心肌损伤，血清cTNⅠ能早期诊断心肌损伤，有较宽的时间窗，可作为诊断心肌损伤的标志物。     

心脏肌钙蛋白Ⅰ测定诊断心肌损伤

目的　探讨心脏肌钙蛋白I(CtnI)测定在心肌损伤诊断中的应用。方法　对 32例急性心肌梗死(AMI)、2 8例病毒性心肌炎 (VM)、30例心绞痛 (AP)、30例原发性高血压 (EH)患者及 2 5例正常健康人血清cTnI、CK、CK -MB、LDH测定。结果　①AMI、VM患者 2 4h血清CtnI阳性率显著高于AP组、EH组、正常对照组 (P <0 .0 0 5 )。②AMI患者 3h内血清cTnI阳性率 5 0 0 % ,显著高于CK ,CK -MB、LDH阳性率 (P <0 .0 5 )。③VM患者2 4h内血清CtnI阳性率 75 0 % ,显著高于CK ,CK -MB、LDH阳性率 (P <0 .0 5 )。VM患者 1周、2周、3周血清cT nI阳性高显著高于CK、CK -MB阳性率 (P <0 .0 1 ) .结论　血清cTnI能早期确诊AMI、VM ,具有较宽的时间窗口 ,对心肌损伤的早期诊断优于心肌酶学 ,是较敏感和特异的血清标志物     

急性胸痛患者心肌肌钙蛋白Ⅰ检测的意义

心肌肌钙蛋白Ⅰ（ｃＴｎⅠ）是新近开发的诊断心肌损伤的新方法，现已经开始用于临床。本文旨在研究对ｃＴｎⅠ急性胸痛患者诊断的临床意义。１对象与方法１．１病例选择：收入我院急性胸痛患者共６１例，其中男４９例，女１２例，年龄在３９岁～８４岁，平均（６３．６±...     

99mTc标记的大肠癌单克隆抗体在小鼠体内分布特点的研究

目的：研究^99m-Tc标记的大肠癌单克隆抗体(^99mTc—ACCmAb)在正常小鼠和荷瘤裸鼠体内的分布及在荷瘤裸鼠体内SPECT成像的研究。方法：将^99m-Tc和^99mTc—ACCmAb分别注射入正常小鼠、荷L010-16人结肠癌裸鼠，按不同时间点采取小鼠的脏器进行同位素放射性活度的测定；并在不同时间测定荷L010-16人结肠癌裸鼠注射^99mTc—ACCmAb的SPECT显像。结果：注射^99mTc后正常小鼠体内6h5min血液中的放射性活度与30min相比下降了76．6％，是30min的23．4％；肝脏中6h5min的放射性活度为30min的27．2％，下降了72．8％。尾静脉注射^99mTc-ACCmAb的正常小鼠，6h5min在血液中的放射性活度与30min血液中的放射性活度比较下降了68．4％，是30min的31．6％，24h为6h5min的6．1％，下降了93．9％；荷瘤裸鼠体内^99mTc-ACCmAb在24h血液中的放射性活度是6h5min的2．1％，下降了97．9％。SPECT显像结果表明，虽然在注射^99mTc-ACCmAb20h血液与肿瘤的比值为最高，但在24h的成像结果仍然好于其他的时间点。结论：^99m-Tc标记的大肠癌单克隆抗体可特异性浓聚于荷L010-16人结肠癌裸鼠模型中，可能成为大肠癌根除手术中使用的手术导向体内诊断用药，保证手术切除肿瘤的彻底性。     

心肌肌钙蛋白Ⅰ的检测与其在心肌损伤中疾病中的临床意义

目的探讨心肌肌钙蛋白的监测和临床应用。方法采用化学发光免疫分析法检测患者CTnⅠ水平,统计其阳性率并与CK-MB阳性率对比。结果 CTnⅠ的检测出阳性率比CK-MB的阳性率要高。结论由于其高度的心肌特异性,对心肌损伤程度的高度敏感性急较长的诊断窗口期,CTnⅠ正逐渐取代CK-MB,成为诊断心肌损伤,特别是针对心肌梗死的特异性标记物。     

On the 99mTc‐labeling of isoniazid with different 99mTc cores

Recent advances in the chemistry of radiolabeling with ^99mTc such as use of the ^99mTc tricarbonyl and ^99mTc–HYNIC cores have revived interest in ^99mTc‐labeling of small biomolecules and further investigation as potential radiopharmaceuticals. Isoniazid, a drug commonly used for treatment of tuberculosis, has been chosen for the present study. Three distinct strategies were utilized to radiolabel isoniazid with ^99mTc. In the direct labeling protocol, the hydrazino amide functional group of isoniazid was used for ^99mTc‐labeling in the HYNIC sense using tricine and EDDA as co‐ligands. The other strategies of ^99mTc‐labeling involved the derivatization of isoniazid to its N, N‐diacetic acid derivative, which in turn was either used as a tridentate ligand for labeling with the [^99mTc(CO)₃(H₂O)₃]⁺ synthon or directly labeled by the conventional route wherein ^99mTc is in the +3 oxidation state. The complexes prepared in >95% yields were characterized by paper chromatography, thin layer chromatography and HPLC. Comparison of the three approaches showed that maximum specific activity and stability was obtained in the ^99mTc–isoniazid derivative synthesized via the tricarbonyl method. However, in vitro cell‐binding studies indicated that none of the ^99mTc–isoniazid complexes prepared had any appreciable uptake in Mycobacterium tuberculosis. Copyright © 2005 John Wiley & Sons, Ltd.     

Development of a lyophilized kit formulation for labeling of DNA probes with 99mTc

DNA fragments such as oligodeoxynucleotides (ODNs) are under investigation for a possible utilization in nuclear medicine. Until now, experiments on ^99mTc-labeled ODNs in vitro or in vivo have required the application of time-consuming procedures to obtain and control the purity of the radiolabeled compound. A lyophilized labeling kit would ease and improve the reproducibility in further investigations with this class of promising biomolecules; therefore a study was initiated to evaluate the suitability of conjugates of ODNs and a bifunctional chelating agent to be part of lyophilized kit formulations. We report here the development of the first kit for one-step labeling of oligonucleotides with ^99mTc. The formulation comprises 250–500 pmol S-benzoyl-mercaptoacetyldiglycine (MAG2)-ODN phosphorothioate conjugate, 5 mg potassium sodium tartrate tetrahydrate and 100 μg stannous chloride dihydrate in a lyophilized kit. Labeling yields above 90% were reproducibly achieved after addition of 0.1–1 GBq pertechnetate and subsequent heating in a boiling water bath. Once formed, the ^99mTc-MAG2-ODN complexes were stable for at least 24 h. The shelf life of the kits is at least 10 weeks when stored protected from light at room temperature, but even kits stored at 40°C gave labeling yields above 90% after 10 weeks.     

Application of 99Mo/99mTc alumina generator in the labeling of metoprolol for diagnostic purposes

Labeling of metoprolol by technetium‐99m in pertechnetate form (^99mTcO) eluted from a ⁹⁹Mo/^99mTc alumina generator in the presence of stannous chloride dihydrate was carried out via chelation reaction. The reaction parameters that affect the labeling yield such as metoprolol concentration, stannous chloride dihydrate concentration, reaction temperature, and pH of the reaction mixture were studied to optimize the labeling conditions. Using 1 GBq ^99mTcO, 500 µg metoprolol as substrate dissolved in 500 µL phosphate buffer at pH 9 and 50 µL of stannous chloride as reducing agent (1 mg/mL) at 25°C for 30 min reaction time, a maximum radiochemical yield of ^99mTc‐metoprolol (92%) was obtained. ^99mTc‐metoprolol was characterized by thin layer chromatography (TLC) and by high pressure liquid chromatography (HPLC). The specific activity of ^99mTc‐metoprolol obtained was 888 MBq/1.88 mmol. The biological distribution in normal mice showed that ^99mTc‐metoprolol is rapidly concentrated after injection in the heart, which indicates its suitability for heart imaging. Copyright © 2009 John Wiley & Sons, Ltd.     

A novel bifunctional chelating agent based on bis(hydroxamamide) for 99mTc labeling of polypeptides

This paper describes the synthesis and biological evaluation of a novel bifunctional chelating agent (BCA) based on bis(hydroxamamide) for ^99mTc labeling of polypeptides. We successfully designed and synthesized C₃(BHam)₂―COOH as a new BCA. C₃(BHam)₂―COOH formed a stable ^99mTc complex and enabled us to prepare ^99mTc‐labeled polypeptides by using a 2,3,5,6‐tetrafluorophenol (TFP) active ester of C₃(BHam)₂―COOH. ^99mTc‐C₃(BHam)₂―HSA prepared with C₃(BHam)₂―TFP was stable in both murine plasma and an excess of l ‐cysteine without any dissociation of ^99mTc from polypeptides. Furthermore, the blood clearance of ^99mTc‐C₃(BHam)₂―HSA in mice was similar to that of ¹²⁵I‐HSA, suggesting that C₃(BHam)₂―COOH retained stable binding between ^99mTc and the polypeptides in vivo. When ^99mTc‐C₃(BHam)₂―NGA was injected into mice, the radioactivity showed high hepatic uptake early on and a rapid clearance from the liver, indicating that C₃(BHam)₂―COOH did not affect the pharmacokinetics of polypeptides in vivo and gave radiometabolites, which displayed a rapid elimination from the liver. Such characteristics would render C₃(BHam)₂―COOH attractive as a new BCA for ^99mTc labeling of polypeptides.     

Radiolabelling rituximab with 99mTc in three steps procedure

Lymphomas are the most frequent haematological malignancy. In non‐Hodgkin's lymphomas (NHL), more than 90% of tumor cells express the cluster of differentiation (CD) 20 antigen. At the end of frontline therapy, the evaluation of remission is based on computed tomography (CT) and positron emission tomography coupled with computer tomography (PET/CT) with [¹⁸F]‐fluorodeoxyglucose ([¹⁸F]FDG). Unfortunately, these techniques are not specific and cannot distinguish residual active tumor from inflammation. The aim of this study was to develop a specific radiotracer of NHL CD 20+ cells for clinical applications. The radiolabelling technique presented, based on the use of tricarbonyl compound, does not include an antibody reduction because this step could damage the protein. Actually, rituximab, an anti‐CD 20 chimeric antibody used for the treatment of these NHL, was radiolabelled with Isolink® ^99mTc‐tricarbonyl compound in a three‐step procedure without using a specific antibody reducer. Radiolabelling yield was greater than 97%. In vitro experiments showed a conservation of antibody integrity. In vivo experiments using Single‐photon emission computed tomography/CT showed significant tumor targeting 24 h after injection of the radiotracer. It was consequently possible to develop an immunoradiolabelling method to specifically detect the residual disease. As this procedure is fast, reproducible and gentle, it will be possible to comply with Good Manufacturing Practices.     

Noninvasive Assessment of Tumor Hypoxia with 99mTc Labeled Metronidazole

Purpose. The assessment of tumor hypoxia by imaging modality prior to radiation therapy would provide a rational means of selecting patients for treatment with radiosensitizers or bioreductive drugs. This study aimed to develop a ^99mTc-labeled metronidazole (MN) using ethylene-dicysteine (EC) as a chelator and evaluate its potential use to image tumor hypoxia. Methods. EC was conjugated to amino analogue of MN using Sulfo-N-hydroxysuccinimide and l-ethyl-3-(3-dimethylaminopropyl) carbodiimide-HCl as coupling agents, the yield was 55%. Tissue distribution of ^99mTc-EC-MN was determined in breast tumor-bearing rats at 0.5, 2, and 4 hrs. Planar imaging and whole-body autoradiograms were performed. The data was compared to that using ^99mTc-EC (control), [^l8F]fluoromisonidazole (FMISO) and [¹³¹I] iodomisonidazole (IMISO). Results. In vivo biodistribution of ^99mTc-EC-MN in breast tumor-bearing rats showed increased tumor-to-blood and tumor-to-muscle ratios as a function of time. Conversely, tumor-to-blood values showed time-dependent decrease with ^99mTc-EC in the same time period. Planar images and autoradiograms confirmed that the tumors could be visualized clearly with ^99mTc-EC-MN from 0.5 to 4 hrs. There was no significant difference of tumor-to-blood count ratios between ^99mTc-EC-MN and [¹³¹I]IMISO at 2 and 4 hrs postinjection. From 0.5 to 4 hrs, both ^99mTc-EC-MN and [¹³¹I]IMISO have higher tumor-to-muscle ratios compared to [¹⁸]FMISO. Conclusions. It is feasible to use ^99mTc-EC-MN to image tumor hypoxia.     

Solid phase preparations of 99mTc labeled radiopharmaceuticals

For the preparation of most ^99mTc radiopharmaceuticals, SnCl₂ has remained the agent of choice for reduction of Tc⁷⁺ to lower valency states, which facilitates its chelation by compounds of diagnostic importance. We have developed a simple technique in which SnCl₂ lyophilized in a glass vial, either alone or on a solid matrix of polymeric microspheres (beads), was used. Tin‐113 (t_1/2 – 115 d) was used as a tracer, which facilitated quantitative assessment of loss or release of tin in the reaction mixtures. The feasibility and efficacy of this technique were examined for preparations of four ^99mTc‐ labeled peptides, in which SnCl₂ was used as a reducing agent for radiolabeling, a procedure well established in our laboratory. Labeling efficiencies for all four peptides using SnCl₂ on solid phase was greater than 95%, as compared to less than 90% (P=0.05) for SnCl₂ lyophilized without the solid matrix. Colloid formation was less than 3% in either case. The stability of SnCl₂ was greater than six months for solid matrix, and less for that without the microspheres. The ¹¹³Sn measured as a daughter product ^113mIn indicated that release of SnCl₂ from microspheres in reaction mixture was 85±3%, as compared to 80±5% lyophilized alone. The recovery of ^99mTc in solution from microspheres was 95–100%. The large size of the microspheres used (649 μm) eliminated the risk of drawing them through a needle in a syringe used for injection of a preparation. Copyright © 2002 John Wiley & Sons, Ltd.     

用微波炉法标记^99mTc—MIBI的技术探讨

目的 通过对微波炉法标记99mTc-MIBI的技术探讨,保证此方法的标记质量和标记过程的安全.方法 首先用微波炉对烧杯内的水进行加热实验,观察被加热液体在旋转托盘不同位置的受热状况;再做空白模拟实验,摸索不引起实验瓶破裂的较长加热时间;在此安全加热时间范围内,逐级增加实际加热标记时间,分别用纸层析法做放化纯测定,确定最合适的标记时间.结果 微波炉旋转托盘的中心位置,火力适中、热力均匀;中档火力加热真空瓶中4ml生理盐水,安全加热时间至少70s;实际标记加热40～50s,99mTc-MIBI的放化纯度可达98%以上.结论 微波炉法标记99mTc-MIBI,安全、可靠、高效,值得推广使用.     

Fast cancer uptake of 99mTc-labelled bombesin (99mTc BN1)

In human blood, breakdown of gastrin-releasing peptide and other bombesin-related peptides occurs in less than 15 min. This quick enzymatic cleavage might impair the diagnostic use of labelled bombesin (BN). 99mTc-labelled bombesin (99mTc BN1) was injected intravenously and dynamic uptake data were acquired for diagnosing 26 cancers of different origin: 15 breast, 3 prostate, 5 colo-rectal, 1 pancreas, 2 small cell lung cancers and 1 gastrinoma. Background subtracted tumour uptake data were plotted against time and fitted with known mathematical functions. Twenty-three out of 26 cancers showed rapid increase of radioactivity followed by a radioactivity plateau, with some oscillations around the average plateau value. The time to 80% of max activity (T80) was the reference parameter to measure and to compare the uptake speeds. The slowest T80 was 7 min in one T1b breast cancer, gastrinoma reached T80 in 5 min and node-positive prostate cancers in 2 min. N+ breast cancers showed T80 at 3.62 +/- 0.75 min, N- breast cancers at 5.5 +/- 0.88 min (p < 0.02). When all the tumours were considered, N+ tumours showed T80 at 2.68 +/- 1.03 min and N- cancers at 5.5 +/- 0.82 min. In all the cancer types, the uptake of 99mTc BN was faster than 10 min. This result shows the ability of 99mTc BN to image tumours. The faster uptake by N+ versus N- cancers probably depends on the higher blood flow in N+ cancers.     

Trifluoroacetyl-HYNIC peptides: synthesis and 99mTc radiolabeling

Fmoc-lys(HYNIC-Boc)-OH, a precursor for solid-phase synthesis of 99mTc-labeled peptides, was synthesized efficiently without HPLC purification. HPLC-ESMS showed that deprotection and decoupling of peptide from the resin with trifluoroacetic acid gave initially HYNIC-peptide, which was trifluoroacetylated upon prolonged incubation. The trifluoroacetyl-HYNIC group was hydrolyzed during 99mTc labeling, rendering deprotection unnecessary. Trifluoroacetyl-HYNIC peptide was 99mTc-labeled as efficiently, producing the same product, as HYNIC-peptide. These modifications enhance the versatility of HYNIC for 99mTc peptide labeling.