肿瘤基因治疗载体的选择及使用安全性的研究进展

随着对肿瘤发生发展分子机制认识的不断深入,肿瘤的基因治疗已成为攻克和治愈肿瘤最具希望和挑战的研究领域。如何建立安全有效的治疗基因导人系统成为研究者们首要解决的问题。目前,常用的载体主要有病毒载体和非病毒载体两类：病毒载体的转移效率高,在基础研究和临床试验中应用广泛,但近年来因存在安全性的问题,其使用受到了一定的制约;非病毒载基因导入的效率相对较低,但具有安全性好且容易制备的特点,日益受到人们的重视。现就近年来国内外对于肿瘤基因治疗载体的使用选择及安全性研究作一综述。     

犬下肢缺血后pUDKH基因治疗对股神经的保护作用

目的：观察pUDKH基因治疗犬下肢缺血后对其神经组织病理学的影响。方法：杂种犬静脉注射戊巴比妥钠麻醉后,结扎左侧股动脉起始部,建立下肢缺血模型。股动脉结扎后即刻,大腿肌肉局部注射pUDK（对照组）或不同剂量pUDKH（pUDKH处理组,0．15、0．3、0．6mg／kg）。术后3个月,取股神经及其周围肌肉组织行病理学检查。结果：对照组股神经及其细小分支均发生显著的退行变,累及轴突、髓鞘和施旺氏细胞核,而经pUDKH处理组各级神经病变不明显,有的甚至与正常犬无差别。结论：pUDKH的局部注射可减轻或阻遏犬下肢缺血后股神经的组织损伤,具有一定的神经组织保护作用。     

载报告基因壳聚糖纳米粒制剂体外转染活性考察

目的 考察壳聚糖纳米粒体外基因转染活性及壳聚糖纳米粒经表面修饰的体外转染活性变化。方法 用复凝聚法制备纳米粒，透射电镜观察粒子形态，体外基因转染实验评价纳米粒的体外转染活性，用倒置荧光显微镜观察和流式细胞仪测定转染结果。通过考察递送不同剂量的基因和转染后不同时间的转染效率，寻找本递送系统较好的转染条件。用纳米粒表面连接PEG以及半乳糖基白蛋白，对纳米粒进行修饰，通过体外转染实验，评价表面修饰对其转染活性的影响。结果 未经表面修饰的载基因纳米粒能够转染人胚胎肾细胞(HEK293)和肝癌细胞(HepG2)，但转染效率仍不如脂质体转染试剂，且在转染实验后约72h较高，递送基因较佳的剂量是4μg，在以上两种细胞中，转染效率也不同。经PEG表面修饰的纳米粒仍保持纳米粒的体外转染活性。连接半乳糖基牛血清白蛋白的纳米粒转染活性却反而略有下降。结论 壳聚糖纳米粒能将基因递送到细胞内，并且报告基因能在细胞内表达。因此，可以用作基因递送的载体系统，值得进一步研究。经PEG表面修饰和冷冻干燥处理,保持生物活性．为基因药物制剂化的可能性提供了证据。对于靶向配基的选择．宜继续进行筛选。     

肿瘤基因治疗中的基因显像

基因显像是肿瘤基因治疗的先导性工作,特别是在药物敏感性基因治疗时为了明确转导的标志基因的定位和分布、基因高表达及其持续时间,以便确定最佳给药时间。介绍了国际上在药物敏感性基因治疗研究中所采用几对标志基因和标志基质如HSV1-tk/ACV或GCV,HSV1-tk/FIAU或FFUdR等进行基因显像的原理、结果及其应用前景。     

肝癌基因治疗研究新进展

肝癌是我国常见的恶性肿瘤,目前治疗方法较多,其中基因治疗是当前热点问题。本文对肝癌基因治疗的几个方面:反义基因治疗、自杀基因治疗、免疫基因治疗、抑癌基因治疗、联合基因治疗、基因载体等方面进行了综述。     

放射技术与基因治疗

基因治疗是一个融合了多学科、多种技术的全新医学领域 ,已成为世界医学界的研究热点。放射学技术可在以下方面中发挥独特作用 :选择靶向治疗位点 ,发展和完善载体导入途径 ,建立监测治疗的影象学方法 ,评估基因表达 ,以及放疗与基因治疗的结合等 ,从而在这一迅速发展的诊断和治疗领域作出特有的贡献     

报告基因显像监测基因治疗研究进展

为评价基因治疗,需要随时对治疗基因的定位和表达进行监测。放射性核素报告基因技术是检测基因表达的最好方法。用基因融合、双顺反子、双启动子及双向转录等重组技术,构建表达报告基因的腺病毒载体,导入靶细胞或组织内,然后注射与报告基因偶合的核素标记的探针,进行PET、SPECT或γ-照相,可无创伤地、重复地定量显示报告基因表达。目前,用于基因治疗的报告基因和报告探针系统有:HSV1-tk(单纯疱疹病毒胸腺嘧啶核苷激酶基因)和碘、氟同位素标记的尿嘧啶、鸟嘌呤的衍生物;突变的多巴胺D2R(多巴胺2型受体)基因和(18F-FESP(18F-氟乙基螺环哌丁苯);SSTr2(生长抑素2型受体基因)和生长抑素类似物等。其中,部分已用于临床试验治疗。     

中药制剂临床应用用药分析

目的:了解我院中药制剂的使用情况,为临床合理用药提供参考依据.方法:(1)统计2009～2011年中药制剂三年间品种及变化;(2)对2009～2011三年使用的中药注射剂的销售金额及用药频度进行排序和分析;(3)抽取2011-03病历100份,统计中药注射剂使用率及使用的合理性.结果:中药制剂使用的品种数变化不大,但品种发生了一定的变化;注射剂使用金额呈逐年上升的局势,临床用药基本合理,但存在一些误区.     

p53基因治疗恶性肿瘤的现状与趋势

恶性肿瘤的治疗包括手术、放疗、化疗和生物治疗 ,基因治疗是生物治疗的主要内容 ,该领域的研究正方兴未艾 ,p53基因治疗恶性肿瘤越来越受到人们的重视。本文对p53基因的结构和功能以及该基因治疗恶性肿瘤的现状和趋势作一综述。1　p53基因治疗恶性肿瘤的理论依据　　p53基因是     

冻干粉抗凝针剂三种皮下注射方法的安全评析

【摘要】 目的 比较三种方法在冻干粉针剂皮下注射抗凝治疗中的安全性及可行性。方法 纳入2018年3月至2019年12月注射用那屈肝素钙抗凝治疗的106例患者,BD注射器组（A组）34例;1 mL无菌注射器组（B组）36例;1 mL无菌注射器+无菌注射针组（C组）36例:1 mL无菌注射器,先替换无菌注射针配制药液后,再更换配套针头皮下注射组,对药液残留量、针头受力后形态变化及并发症进行评价。结果 加药后针头倾斜发生率及倾斜度:42.5%、35.18°±17.12°（A组）, 20.0%、18.00°±13.97°（B组）,P＜0．05;加药后针尖倒钩发生率及倒钩角度:57.5%、19.83°±17.14°（A组）,35.0%、11.79°±8.55°（B组）,P＜0．05;注射部位皮下出血发生率及疼痛评分:17.23%、2.90±0.54（A组）,11.90%、1.6±0.49（B组）,4.96%、0.70±0.64（C组）,P＜0．05;冻干粉针剂西林瓶（以下简称西林瓶）瓶内药液残留量:（0.05±0.01） mL（A组）,（0.11±0.06） mL（B组）,0.01±0.00 mL（C组）,P＜0.05;针头腔内药液残留量:0.005±0.001 mL（A组）,0.013±0.007 mL（B组）,（0.03±0.003） mL（C组）,P＜0.05;抽液时间:（7.23±0.96） s（A组）,（5.09±0.52） s（B组）,（1.84±0.22） s（C组）,P＜0．05。 结论 冻干粉针剂皮下注射抗凝治疗中,使用1 mL注射器,先替换无菌注射针充分溶解冻干粉后静置5 s,瓶底抽取药液后,再更换配套针头皮下注射的方案,具有较高的药液利用率,在注射部位物理性损伤、并发症发生率、护理时效的安全性及可行性方面,明显优于BD注射器组及1mL注射器不换针头配制药液组。     

Practical considerations for electron therapy planning and preparation

This Clinic recently commissioned its first electron beams for radiation therapy. Over the past twelve months at this institution, we have developed devices and techniques to obtain precise and reproducible electron therapy treatments. These devices and methods have been used in the treatment of irregularly shaped fields for areas of complex shape, or those adjacent to critical or radiosensitive tissues and areas where it has been cosmetically unsuitable for patients to carry treatment field markings. This paper describes the techniques used in six representative cases with due consideration to physics, dosimetry and practical aspects. Several recommendations result from our experiences here.     

Radionuclide reporter gene imaging for cardiac gene therapy

INTRODUCTION: In the field of cardiac gene therapy, angiogenic gene therapy has been most extensively investigated. The first clinical trial of cardiac angiogenic gene therapy was reported in 1998, and at the peak, more than 20 clinical trial protocols were under evaluation. However, most trials have ceased owing to the lack of decisive proof of therapeutic effects and the potential risks of viral vectors. In order to further advance cardiac angiogenic gene therapy, remaining open issues need to be resolved: there needs to be improvement of gene transfer methods, regulation of gene expression, development of much safer vectors and optimisation of therapeutic genes. For these purposes, imaging of gene expression in living organisms is of great importance. In radionuclide reporter gene imaging, "reporter genes" transferred into cell nuclei encode for a protein that retains a complementary "reporter probe" of a positron or single-photon emitter; thus expression of the reporter genes can be imaged with positron emission tomography or single-photon emission computed tomography. Accordingly, in the setting of gene therapy, the location, magnitude and duration of the therapeutic gene co-expression with the reporter genes can be monitored non-invasively. In the near future, gene therapy may evolve into combination therapy with stem/progenitor cell transplantation, so-called cell-based gene therapy or gene-modified cell therapy. CONCLUSION: Radionuclide reporter gene imaging is now expected to contribute in providing evidence on the usefulness of this novel therapeutic approach, as well as in investigating the molecular mechanisms underlying neovascularisation and safety issues relevant to further progress in conventional gene therapy.     

股骨头缺血性坏死的基因治疗与影像学观察

股骨头缺血性坏死是骨科难治疾病之一,如早期得不到及时有效的治疗,可引起股骨头塌陷、变形,最终导致髋关节功能障碍.基因治疗是新近发展起来的一项新技术,随着分子生物学的发展和基因转移技术的成熟,治疗性血管生成为股骨头缺血性坏死的治疗提供了新的思路.综述股骨头缺血性坏死的基因治疗现状及影像学检查的作用.     

PET for evaluation of differential myocardial perfusion dynamics after VEGF gene therapy and laser therapy in end-stage coronary artery disease.

The purpose of this study was to appraise the value of PET in the assessment of the effect of supposedly proangiogenic new therapies such as gene therapy with vascular endothelial growth factor (VEGF) gene and endomyocardial laser therapy. METHODS: Thirty-five patients with end-stage coronary artery disease and class III (Canadian Cardiovascular Society) angina were included. Myocardial ischemia was evaluated with dipyridamole PET scanning and exercise tolerance with bicycle ergometry. Ten patients were treated with naked plasmid DNA encoding for human VEGF165 (VEGF) and 12 patients were treated with laser therapy (direct myocardial revascularization [DMR]) using an electromechanical mapping system. Thirteen patients were treated with standard medical therapy (control). RESULTS: In both active treatment groups, angina was reduced in most subjects, except in 2 VEGF and 5 DMR patients. In the control group, no improvement in anginal classification was found, except in 3 subjects. On the PET scan, solely in the VEGF group, the stress perfusion was significantly improved (from 57 +/- 33 to 81 +/- 55 mL/min/100 g; P = 0.031). Furthermore, in the VEGF group, the number of ischemic segments was reduced from 274 +/- 41 to 234 +/- 48 segments (P = 0.004) but not in the DMR group (from 209 +/- 43 to 215 +/- 52 segments) or in the control group (from 218 +/- 18 to 213 +/- 28 segments). Bicycle exercise duration showed slight nonsignificant changes in the VEGF group (from 3.6 +/- 2.0 to 4.6 +/- 2.1 min), in the DMR group (from 5.1 +/- 1.5 to 4.7 +/- 1.3 min), and in the control group (from 3.3 +/- 1.8 to 3.5 +/- 2.3 min). CONCLUSION: PET showed that intramyocardial gene therapy with the human VEGF165 gene in contrast to laser DMR treatment effectively reduces myocardial ischemia.     

祖师麻止痛喷雾剂的安全性评价

目的:对祖师麻止痛喷雾剂进行安全性评价。方法:对祖师麻止痛喷雾剂进行小鼠急性毒性半数致死量(LD50)实验;豚鼠全身过敏性实验;家兔皮肤刺激性及毒性实验。结果:小鼠皮下注射祖师麻止痛喷雾剂后LD50为(9.78～10.48)ml/kg;与空白对照组比较,未观察到祖师麻止痛喷雾剂发生过敏性、皮肤刺激性及毒性反应。结论:祖师麻止痛喷雾剂应用于受试动物安全性较好。     

A simplified method for preparation of 99mTc-annexin V and its biologic evaluation for in vivo imaging of apoptosis after photodynamic therapy.

Apoptosis is the likely mechanism behind the effects of chemotherapeutic and radiation treatments, rejection of organ transplants, and cell death due to hypoxic-ischemic injury. A simplified method capable of imaging apoptosis in living animals could have many applications leading to understanding of the involvement of apoptosis in biologic and therapeutic processes. To accomplish this goal we developed a method for the preparation of (99m)Tc-annexin V and evaluated its usefulness to detect apoptosis that occurs during tumor shrinkage after photodynamic therapy (PDT). PDT is a cancer treatment modality that leads to rapid induction of apoptosis both in vitro and in in vivo animal models. METHODS: A novel synthesis of (99m)Tc-annexin V was performed in a simple 1-pot procedure. Radiation-induced fibrosarcoma (RIF-1) tumors grown in C(3)H mice were treated with PDT, followed by injection of (99m)Tc-annexin V and measurement of its tumor uptake at 2, 4, and 7 h after PDT by autoradiography. RESULTS: The radiochemical purity of (99m)Tc-annexin V was >95%. At all time points, (99m)Tc-annexin V was clearly imaged in the PDT-treated tumors, whereas the untreated tumors showed no uptake of the radiolabeled compound. Histopathology and immunohistochemistry of PDT-treated tumors confirmed the evidence of apoptosis compared with untreated tumors. CONCLUSION: These data demonstrate the detection of apoptosis using (99m)Tc-annexin V in tumor tissue in living animals after PDT treatment. This novel technique could be used as a noninvasive means to detect and serially image tissues undergoing apoptosis after cancer treatment protocols in humans. Other potential applications of this technique could be the diagnosis of several human disorders, such as myocardial ischemia or infarct, rejection of organ transplantation, and neonatal cerebral ischemia.