^131I标记凝集素PNA在荷人胃癌裸鼠体内的分布

采用Ｉｏｄｏｇｅｎ法将放射性１３１Ｉ与花生凝集素（ＰＮＡ）进行标记，经腹腔注射１３１Ｉ－ＰＮＡ标记物到荷人胃癌裸鼠体内，在不同时间测定组织放射分布和γ照相。给药后第３天，肿瘤组织放射性强度是血液的４．３０倍，是正常肝组织的３．７６倍，是肌肉组织的３．８９倍；给药后第７天，肿瘤组织浓集１３１Ｉ－ＰＮＡ是正常胃组织的４．２１倍，是小肠组织的６．０５倍，是大肠组织的５．１３倍。４８小时可见肿瘤显像，７２小时显像清晰。本实验结果表明，凝集素ＰＮＡ在胃癌定位诊断和导向治疗中有着潜在的应用价值，对于人体某些表达Ｔ抗原的腺癌都可能具有作为导向治疗载体的研究前景。     

Iodine-131 MIBG scintigraphy in small cell lung cancer

There is a well documented relationship between small cell carcinoma of the lung and the amine precursor uptake and decarboxylation system of endocrine cells (APUD). We attempted to exploit this association by employing the unique radiopharmaceutical,¹³¹I-MIBG, which is recognized and taken up by the APUD system to monitor disease activity in patients with small cell carcinoma of the lung. A total of eight patients with biopsy proven, metastatic small cell carcinoma of the lung were studied.¹³¹I-MIBG was synthesized in our laboratory by reacting metaiodobenzylamine synthesized in our laboratory by reacting metaiodobenzylamine hydrochloride with cyanamide with subsequent solid phase radioiodination. A dose of 0.5 mCi radiopharmaceutical was injected and images obtained on a large field of view gamma camera with a high energy parallel hole collimator at 2, 24, and either 48 or 72 h. Images were compared with known focal areas of metastatic disease demonstrable on computed tomographic scan, chest roentgenogram or bone scan. We were unable to detect reproducible correlations between the images produced by conventional radiographic techniques and the images produced by our radiopharmaceutical. We conclude that this agent will probably not be useful for localization of metastatic small cell lung carcinoma.This work was supported by a Pilot Research Grant from the Education and Research Foundation of the Society of Nuclear Medicine     

Repeated injections of 131I-rituximab show patient-specific stable biodistribution and tissue kinetics

Purpose It is generally assumed that the biodistribution and pharmacokinetics of radiolabelled antibodies remain similar between dosimetric and therapeutic injections in radioimmunotherapy. However, circulation half-lives of unlabelled rituximab have been reported to increase progressively after the weekly injections of standard therapy doses. The aim of this study was to evaluate the evolution of the pharmacokinetics of repeated ¹³¹I-rituximab injections during treatment with unlabelled rituximab in patients with non-Hodgkins lymphoma (NHL).Methods Patients received standard weekly therapy with rituximab (375 mg/m²) for 4 weeks and a fifth injection at 7 or 8 weeks. Each patient had three additional injections of 185 MBq ¹³¹I-rituximab in either treatment weeks 1, 3 and 7 (two patients) or weeks 2, 4 and 8 (two patients). The 12 radiolabelled antibody injections were followed by three whole-body (WB) scintigraphic studies during 1 week and blood sampling on the same occasions. Additional WB scans were performed after 2 and 4 weeks post ¹³¹I-rituximab injection prior to the second and third injections, respectively.Results A single exponential radioactivity decrease for WB, liver, spleen, kidneys and heart was observed. Biodistribution and half-lives were patient specific, and without significant change after the second or third injection compared with the first one. Blood T_1/2, calculated from the sequential blood samples and fitted to a bi-exponential curve, was similar to the T_1/2 of heart and liver but shorter than that of WB and kidneys. Effective radiation dose calculated from attenuation-corrected WB scans and blood using Mirdose3.1 was 0.53+0.05 mSv/MBq (range 0.48–0.59 mSv/MBq). Radiation dose was highest for spleen and kidneys, followed by heart and liver.Conclusion These results show that the biodistribution and tissue kinetics of ¹³¹I-rituximab, while specific to each patient, remained constant during unlabelled antibody therapy. RIT radiation doses can therefore be reliably extrapolated from a preceding dosimetry study.     

Treatment of hepatocellular carcinoma by means of radiopharmaceuticals

Several techniques have been developed for radionuclide therapy of hepatocellular carcinoma (HCC). Medical literature databases (Pubmed, Medline) were screened for available literature and articles were critically analysed as to their scientific relevance. In a palliative setting, intra-arterial administration of ¹³¹I-Lipiodol yields responses in 17–92% of patients. According to a randomised study, ¹³¹I-Lipiodol was far better tolerated than classic chemo-embolisation. The additive value of a single ¹³¹I-Lipiodol administration following partial liver resection for HCC was evaluated and evidence is available that adjuvant radionuclide treatment reduces the recurrence rate. Data concerning the role of ¹³¹I-Lipiodol in bridging patient to liver transplantation are scarce but suggest a potential benefit in terms of reducing the drop-out rate while patients are listed for transplantation. ¹⁸⁸Re- and ⁹⁰Y-labelled conjugates are emerging and initial clinical data are promising. Treatment of HCC with ⁹⁰Y-labelled microspheres is likely as efficacious as treatment with radiolabelled Lipiodol but pretreatment ^99mTc-MAA scintigraphy is required in order to exclude patients with significant lung shunting. Several antibodies targeting antigens expressed on HCC have been radiolabelled, almost exclusively with ¹³¹I, and evaluated in a preclinical or clinical setting. The use of radiolabelled Lipiodol and microspheres allows for selective targeting of HCC with limited toxicity. Prospective, randomised controlled trials demonstrating that both treatment modalities may provide a survival benefit in a palliative setting are mandatory. In addition, future research should focus on the complementary role of radionuclide treatment in patients at risk for recurrent disease following partial liver resection or while awaiting liver transplantation.     

Autologes131J-Humanfibrinogen zur Thrombosefrühdiagnostik

Zusammenfassung Es wird eine Herstellungsmethode von autologem¹³¹J-Humanfibrinogen angegeben.Das Präparat wird charakterisiert in vitro durch Fibrinogengehalt, Proteingehalt, Plasminogengehalt, Gerinnbarkeit und Molekulargewicht der Einzelketten. In vivo werden Verlaufskurven der Gesamtplasmaaktivität, der spezifischen Aktivität, der nicht proteingebundenen Aktivität, der biologischen Halbwertszeit und des Verhaltens am Ort der Thrombose dargestellt.An diesen Kriterien gemessen, erwies sich das autologe¹³¹J-Humanfibrinogen zur Thrombosefrühdiagnostik als voll geeignet.Mit Unterstützung der Deutschen Forschungsgemeinschaft Wu 77/2     

131I-碘化油局部注射对大鼠肝癌模型的疗效研究

目的研究经不同方法局部注射131I-碘化油后对瘤体的损伤效应.方法建立SMMC-7721肝癌皮下移植瘤大鼠模型,分别采用直形注射针线状退行注射(3条线)和弧形套针单点分段旋转扇形注射法,经皮向肿瘤内注射131I-碘化油(0.1×37 MBq/cm3),观察给药后一定时间段大鼠体重、肿瘤大小的变化和动物存活时间,同时以穿刺针和小剪刀取材按常规方法制备病理切片和超薄切片,观察并比较两种给药方法肿瘤组织的形态学变化. 结果直形针给药组大鼠在注射后2周多数表现为体重下降,肿瘤增大,最后都死于全身耗竭;而弧形针组大鼠体重相对稳定,肿瘤组织表现为均匀坏死,缓慢崩溃,动物存活期明显比前者长.直形针给药组肿瘤组织早期表现为大片的组织坏死,晚期表现为存活区域的增加,坏死区域与存活区域界限分明,两者间多有移行带;弧形针分段扇形注药者早期、晚期组织均表现为大片坏死,肿瘤间质内可见淋巴细胞浸润和纤维结缔组织增生;各时间段的检测标本中都可见一定数量的凋亡细胞,但比例远远小于坏死的肿瘤细胞. 结论弧形针分段扇形注射是较为理想的给药方式;"坏死"是治疗剂量131I-碘化油内放疗对瘤体的主要损伤效应.     

Comparison of radioiodine biokinetics following the administration of recombinant human thyroid stimulating hormone and after thyroid hormone withdrawal in thyroid carcinoma

Iodine kinetics were studied in patients with differentiated thyroid cancer while euthyroid under exogenous thyroid stimulating hormone (TSH) and while hypothyroid to detect differences in radioiodine uptake, distribution and elimination. Nine patients with total or near-total thyroidectomy on thyroid hormone suppressive therapy received two or three daily doses of 0.9 mg recombinant human TSH (rhTSH) followed by administration of a diagnostic activity of 2 mCi (74 MBq) iodine-131. After the biokinetics assessments had been performed, patients stopped taking thyroid hormones to become hypothyroid. A second 2 mCi (74 MBq) diagnostic activity of ¹³¹I was administered, followed by a second set of biokinetics assessments. One week later the patients underwent remnant ablation with a therapeutic activity of ¹³¹I. A comparison of the ¹³¹I kinetics in the patients while euthyroid and while hypothyroid showed major differences in the doses to the remnant as well as in residence times and radiation exposure to the blood. In the first diagnostic assessment the remnant dose was higher in eight of the nine patients and clearance of the activity from the blood was faster in all of them. The data from this study suggest that radioiodine administration is potent and safe when administered to euthyroid patients following rhTSH administration. Enhanced residence time in the remnant and decreased radiation exposure to the blood were noted when patients were euthyroid compared to when they were rendered hypothyroid. However, all patients received diagnostic activities in the same order: first while euthyroid, followed by hypothyroidism. It is quite possible that "stunning" from the radioiodine administered in the initial uptake study inhibited the subsequent uptake of radioiodine by the remnant lesions in the second uptake study.     

Evaluation of the novel antiepileptic drug,AWD 131-138, for benzodiazepine-like discriminative stimulus and reinforcing effects in squirrel monkeys

AWD 131-138 [1-(4-chlorophenyl)-4-morpholino-imidazolin-2-one], a new low-affinity partial benzodiazepine receptor agonist with potent anticonvulsant and anxiolytic properties in rodent models, was studied in squirrel monkeys trained to discriminate intramuscular (i.m.) injections of midazolam (0.3 mg/kg) from injections of vehicle. Diazepam produced midazolam-like responding at cumulative doses of 1.0 and 3.0 mg/kg i.m. and decreased rates of responding at 3.0 mg/kg (plasma levels of about 400 ng/ml). In contrast, AWD 131-138 did not produce midazolam-like responding or alter response rates at cumulative doses up to 18.0 mg/kg i.m. (plasma levels over 2100 ng/ml). Other monkeys were trained to intravenously (i.v.) self-administer cocaine (56.0 microg/kg/injection). When AWD 131-138 (10-100 microg/kg/injection) was studied by substitution, responding declined to vehicle substitution levels within three sessions. At the dose of 100 microg/kg i.v. AWD 131-138, sufficient drug was self-administered during the first session (about 3.5 mg/kg) to produce plasma levels above 1000 ng/ml, yet responding over the next two sessions dropped to vehicle levels. The failure of AWD 131-138 to produce benzodiazepine-like discriminative effects and the absence of drug self-administration behavior when substituted for cocaine suggest that its abuse liability is low.     

核医学检查对早期亚甲炎的诊断价值

目的评价核素显像对于早期亚甲炎的诊断价值.方法对239例早期亚甲炎病人进行甲状腺吸131I率、血清甲状腺激素测定及甲状腺显像.结果以吸131I率和激素测定结果的"分离现象"为指标,诊断符合率为91.6%;甲状腺显像异常影像检出率高达96.2%.结论"分离现象"对早期亚甲炎的诊断灵敏度高、特异性强.核素显像在灵敏反映甲状腺功能的基础上,能直观显示病变范围及其受损程度,从而为早期亚甲炎的诊断及病情评价提供客观依据.     

The infant with possible biliary atresia: Evaluation by ultrasound and nuclear medicine

Twenty-eight infants with jaundice were evaluated with ultrasound and radionuclide scans. Comparison of these studies with pathologic, surgical and clinical examinations demonstrated good correlation between ultrasonic and radionuclide studies. Ultrasound is an important preliminary study in the workup of such patients. Combined imaging provides the most information in a patient with suspected biliary atresia.