氟[18F]化钠PET/CT临床应用进展

氟[18F]化钠(18F-NaF)是一种正电子发射计算机断层显像(PET)药物,主要用于诊断成骨性反应活跃的骨疾病,尤其是恶性肿瘤骨转移的诊断.由于药物本身的特性以及PET/CT相对于单光子发射计算机断层显像(SPECT)/CT的优势,18F-NaF PET/CT显像相比于99Tc-m亚甲基二膦酸盐(99Tcm-MDP...     

NCI-H446细胞的~(125)Ⅰ-[Tyr~3]octreotide受体分析

目的 :探讨小细胞肺癌与 [Tyr3 ]octreotide (TOC)的亲和力。方法 :用氯胺T方法标记的12 5I-TOC作为配基 ,检测小细胞肺癌细胞株NCl-H4 4 6与其结合的受体位点数及亲和常数。结果 :氯胺T法标记的12 5I-TOC经SephadexG - 10纯化后放化纯大于 95 % ;受体分析显示NCI-H4 4 6表达的生长抑素受体多 (Bmax =1 17× 10 5受体位点 /细胞 ) ,与12 5I-TOC亲和力强 (Kd =0 5 8nM)。结论 :TOC的标记物可用于小细胞肺癌肿瘤的受体显像及放射治疗。     

酶联免疫法(ELISA)在检测肝纤维化指标中的应用

目的探讨酶联免疫法(ELISA)在检测血清透明质酸(HA) 、Ⅲ型前胶原(PCⅢ) 、Ⅳ型胶原(CIV)、层粘蛋白(LN)中的应用.方法利用ELISA与放射免疫分析法(RIA)分别检测116例慢性肝炎组、215例正常组和36例肝硬化组的血清HA、PCⅢ、CIV、LN,比较二者的优缺点.结果两种方法结果无差异(p>0.05).结论 ELISA法准确、简便和安全,可代替RIA法.     

Solid-phase analysis method for (S)-[18F]fluorocarazolol and its metabolites

(S)-[18F]Fluorocarazolol is a radiopharmaceutical developed to quantitatively assess beta-adrenergic receptors in vivo via positron emission tomography imaging. Since radioactive metabolites of (S)-[18F]fluorocarazolol rapidly appear in the plasma, methods for conveniently and reliably evaluating plasma for (S)-[18F]fluorocarazolol content are required. Here we present methods and validation of an approach using commercial extraction cartridges that is faster and more convenient than an approach using internal-surface reverse-phase chromatography but yields comparable results.     

Imaging of cellular proliferation in liver metastasis by [18F]fluorothymidine positron emission tomography: effect of therapy

Although [(18)F]fluorothymidine positron emission tomography (FLT-PET) permits estimation of tumor thymidine kinase-1 expression, and thus, cell proliferation, high physiological uptake of tracer in liver tissue can limit its utility. We evaluated FLT-PET combined with a temporal-intensity information-based voxel-clustering approach termed kinetic spatial filtering (FLT-PET(KSF)) for detecting drug response in liver metastases. FLT-PET and computed tomography data were collected from patients with confirmed breast or colorectal liver metastases before, and two weeks after the first cycle of chemotherapy. Changes in tumor FLT-PET and FLT-PET(KSF) variables were determined. Visual distinction between tumor and normal liver was seen in FLT-PET(KSF) images. Of the 33 metastases from 20 patients studied, 26 were visible after kinetic filtering. The net irreversible retention of the tracer (Ki; from unfiltered data) in the tumor, correlated strongly with tracer uptake when the imaging variable was an unfiltered average or maximal standardized uptake value, 60 min post-injection (SUV(60,av): r = 0.9, SUV(60,max): r = 0.7; p < 0.0001 for both) and occurrence of high intensity voxels derived from FLT-PET(KSF) (r = 0.7, p < 0.0001). Overall, a significant reduction in the imaging variables was seen in responders compared to non-responders; however, the two week time point selected for imaging was too early to allow prediction of long term clinical benefit from chemotherapy. FLT-PET and FLT-PET(KSF) detected changes in proliferation in liver metastases.     

[~(125)I]-(A14)单碘胰岛素在荷人肝癌裸鼠体内的趋瘤特性研究

目的 :观察放射性碘标记胰岛素在荷人肝癌裸鼠体内的趋瘤或亲肿瘤 (tumor-seeking)特性。方法 :采用荷人肝癌裸鼠模型。用 [12 5I]- (A14)单碘胰岛素进行荷人肝癌裸鼠体内分布实验和抑制实验。结果 :体内分布实验显示肝癌组织摄取 [12 5I]- (A14)单碘胰岛素明显高于本底组织 (肌肉 ) ,肿瘤与血和肿瘤与肌肉的放射性比值随时间延长而增高。体内抑制实验发现肿瘤组织于 30min的抑制率为 35 .0 %。结论 :[12 5I]- (A14)单碘胰岛素在荷人肝癌裸鼠体内 ,通过受体介导作用 ,能被肝细胞癌组织特异性摄取。     

Fate of 2-deoxy-2-[18F]fluoro-D-glucose in hyperglycemic rats

Sustained hyperglycemia allows the preferential labelling of pancreatic glycogen by D-[U-14C]glucose in control rats, as compared to animals previously injected with streptozotocin (STZ rats). The major aim of the present study was to investigate whether a sizeable difference between control and STZ rats could also be observed in terms of the radioactive content of the pancreatic gland 8 h after the intravenous injection of 2-deoxy-2-[18F]fluoro-D-glucose, both types of animals being examined at the same level of hyperglycemia. Although the radioactive content of muscle, liver and kidney was lower in STZ rats than in control animals, such a difference failed to achieve statistical significance in brain, hypophysis, pancreas and parotid gland. It is proposed, therefore, that 11C-labelled D-glucose, rather than 2-deoxy-2-[18F]fluoro-D-glucose should be used in the perspective of the non-invasive imaging of the endocrine pancreas.     

人工神经网络在超声无创定量诊断肝纤维化中的初步应用

目的研究人工神经网络用于超声定量分级诊断肝纤维化的可行性。方法选择2005年9月～2007年6月146例超声引导肝脏穿刺病理证实为肝纤维化患者,其中男性103例,女性43例,年龄14-77岁（平均年龄47．6岁）：其中2005年9月-2006年12月收集的81例肝纤维化患者（男性54例,女性27例）及22例正常对照人群的超声影像数据作为训练样本集;2007年1月～2007年6月收集的65例肝纤维化患者及53例正常人群的超声影像数据对人工神经网络进行评价。先对81例肝纤维化患者及22例正常人超声影像数据经统计学分析筛选出有意义的7项指标纳为诊断指标,初步建立超声诊断肝纤维化分级的人工神经网络模型,再将65例肝纤维化患者及53例正常人的超声影像数据用于人工神经网络的评价。结果以肝实质、肝脏边缘、脾脏大小及门静脉平均血流速度4项指标作为人工神经网络模型的输入层,以病理诊断分级结果为输出层,建立人工神经网络模型,该模型对肝纤维化分级诊断的敏感度95．4％,特异度96.2％,准确度95．8％,尤登指数0．916。结论建立的人工神经网络进行超声诊断肝纤维化分级具有较高的敏感度及特异度,值得进一步探讨。     

用于放射性核素铼标记的fac-[^188Re（CO）3（H2O）3]^＋的制备研究

目的：探讨放化中间体fac-[188Re（CO）3（H2O）3]＋的合成条件,并对其进行优化研究。方法：参照Schibli介绍的方法进行放化中间体fac-[188Re（CO）3（H2O）3]＋的合成,分别从反应温度、反应时间和反应物BH3.NH3的用量对合成fac-[188Re（CO）3（H2O）3]＋产率的影响进行观察。结果：合成放化中间体fac-[188Re（CO）3（H2O）3]＋的最佳反应条件为：反应时间为15min,反应温度为70℃,BH3.NH3的用量为5mg;pH值〈2。在最佳的反应条件下,产物的放化产率为85%,经Sep-Pak（硅胶柱分离后,放化纯度〉95%。结论：本文结果为放化中间体fac-[188Re（CO）3（H2O）3]＋标记生物分子作为新一代治疗药物的发展提供了有力的实验基础。     

Fate of 2-deoxy-2-[18F]fluoro-D-glucose in control and diabetic rats

Recent experiments conducted in vitro have documented a marked difference in the time course for D-[U-14C]glucose net uptake by pieces of pancreatic tissue versus isolated pancreatic islets. The present study aimed, therefore, at assessing whether the endocrine pancreas contributes to a detectable extent to the overall net uptake of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) by the pancreatic gland. For this purpose, the radioactive content of the pancreas was compared to that of plasma, erythrocytes, liver, brain, hypophysis and parotid gland 3 min, 15 min and 240 min after the intravenous injection of FDG to both control rats and animals injected with streptozotocin and later treated with insulin or not. In the control rats, the radioactive content (cpm/mg wet wt.) of erythrocytes was always lower than that of liver. In other organs, it displayed the following hierarchy pancreas < parotid < hypophysis < brain, the absolute values being either lower (3 min) or much higher (240 min) than in liver. In the diabetic rats, whether treated with insulin or not, the radioactive content of erythrocytes, pancreas, brain, hypophysis and parotid gland, relative to the paired value found in liver, was equal or lower than that of control rats when the animals were hyperglycemic and equal or higher than that of control rats when the animals became hypoglycemic as the result of intensive insulin treatment. Even only 3 min after the injection of FDG, and despite persistent hyperglycemia in the streptozotocin-injected and insulin-treated rats, the pancreas/ liver paired ratio in radioactive content failed to be significantly lower in the diabetic animals than in control rats. These findings indicate that 2-deoxy-2-[18F]fluoro-D-glucose is not a suitable tool to detect any preferential labelling of insulin-producing cells, relative to acinar cells, at least when considering only the total radioactive content of the pancreatic gland.     

肝纤维化的影像学诊断研究进展

肝纤维化（hepatic fibrosis）是肝脏慢性损伤修复及愈合的结果,这种修复通常包括炎症细胞或者免疫细胞在损伤部位的聚集,细胞外基质蛋白的分泌以及肝脏组织的再生。肝纤维化是肝硬化的早期可逆阶段,如不及时治疗则可能进展成为失代偿期肝硬化并出现各种并发症。     

混合物脑肽干预对肝纤维化大鼠模型的影响

背景：混合物脑肽是从动物脑中提取的多肽混合物,含有神经生长因子成分。近年研究发现,神经生长因子与肝损伤密切相关。 目的：使用自拟混合物脑肽观察对大鼠肝纤维化的影响。 方法：利用四氯化碳诱导形成SD大鼠肝纤维化模型。将大鼠随机分成纤维化模型组、脑肽干预组和对照组。4,8周采集标本。通过活体解剖取门静脉血清采用全自动生化分析仪检测肝功能丙氨酸氨基转移酶、天冬氨酸氨基转移酶、总胆红素、白蛋白;采用放射免疫法检测血清肝纤维化指标透明质酸、层粘连蛋白、Ⅲ型前胶原;常规苏木精-伊红和网状纤维染色检测肝组织标本。 结果与结论：大鼠肝纤维化模型成功建立。脑肽干预组纤维化程度较纤维化模型组显著减轻,但肝组织炎症和肝细胞脂肪变性反而较纤维化模型组更显著。初步判断脑肽能够阻断四氯化碳诱导的肝纤维化,可能与神经生长因子有关。