牙齿修复相关转基因研究：显微注射法获得pTet-on-CX转基因工具小鼠G0代的实验观察

目的：为便于进行规模化的转基因研究，构建一种四环素调控性转基因体系中的工具小鼠系。方法：实验于2002—06／10在上海南方模式生物研究中心完成。以cβ—actin启动子取代pTet—on—NSE质粒中的NSE启动子，构建转基因载体pTet-on-CX；将XhoⅠ酶切线性化的载体DNA注射到小鼠受精卵的雄原核，移植到假孕母鼠的输卵管。仔鼠出生后，经PCR及Southern Blotting检测阳性小鼠。结果：注射的受精卵共存活603枚，移卵后产仔64只，阳性6只。阳性鼠分别传代开始建系。结论：通过显微注射的方法获得pTet—on—CX转基因工具小鼠的G0代，为规模化的转基因研究(包括与牙齿修复有关的基因，如牙本质涎磷蛋白基因)奠定了基础。     

小鼠心肌内转基因后压力超负荷模型的实验研究

目的::探索在短时间内建立小鼠心肌内转基因后压力超负荷模型,为深入研究心脏肥大的分子机制提供可靠的实验对象。方法:雄性C57BL/6小鼠随机分为升主动脉缩窄组(手术组)和同期假手术组(对照组),手术组根据暂时阻断主动脉血流5s、10s、20s、30s同时左心腔内分别注射Ad-LacZ或PBS后又分为LacZ组和PBS组,观察术后4周不同时间小鼠体重、颈动脉血压和心脏超声等变化HE染色和X-gal染色分别观察心肌肥厚情况和基因转染情况。结果:手术成活率88.8%。升主动脉缩窄小鼠的血压较对照组明显升高。缩窄术后2周心肌明显肥厚,4周时出现失代偿性心力衰竭。X-gal染色显示阻断血流5s以上心脏有蓝染,但10s、20s、30s之间无明显区别。结论:该方法简单有效,重复性好,可在短时间内建立小鼠心肌内转基因和压力超负荷心肌肥厚模型,为心脏肥大的深入研究提供可靠的实验对象。左心室心腔直接注射转染Ad-LacZ基因同时阻断升主动脉血流10s以上可以使目的基因有较好的表达。     

结蛋白相关心肌病转基因小鼠桥粒相关蛋白表达和分布的变化

目的 通过观察结蛋白相关心肌病(desmin-related cardiomyopathy，DRC)转基因小鼠桥粒相关蛋白表达和分布的变化。以探讨其发病机制。方法 应用Western印迹和免疫标记共聚焦显徽镜观察桥粒斑蛋白（desmoplakin，DP)和plakodobin(PG)在1个月小鼠心室肌组织中的表达和分布。结果 突变型结蛋白转基因小鼠(D7-des)较野生型结蛋白转基因小鼠(WT-des)和非转基因小鼠(NTG)DP总蛋白和细胞骨架蛋白部分(TIF)明显升高。免疫标记心肌组织DP分布在细胞的两端、侧面和胞质，且密度显著增加，而WT-des与NTG比较无明显变化；3组动物之间，PG没有变化；免疫标记显示D7-des结蛋白排列紊乱。失去正常的结构。结论 该研究首次发现突变结蛋白破坏了结蛋白和桥粒结构的完整性，影响了心肌细胞机械耦联，可能与DBC舒缩功能异常和心力衰竭的发生有关。     

阿尔茨海默病转基因小鼠早期记忆功能障碍与氧化应激损伤关系的实验研究

目的 观察转APP/PS1基因阿尔茨海默病(AD)小鼠(APP/PS1小鼠)早期空间学习记忆功能及相关氧化应激反应指标的变化,并探讨它们之间的相关性.方法 应用Morris水迷宫评定APP/PS1小鼠及相应野生型(WT)小鼠的空间学习记忆功能,采用ELISA方法检测脑组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)活性以及丙二醛(MDA)和蛋白质羰基的含量,并进行相关性分析.结果 2组小鼠的空间学习能力无明显差异(P＞0.05),而APP/PS1小鼠在目标象限(定位航行实验中平台所置第二象限)中航行时间占总时间的百分比(29.02±4.27)%较WT小鼠(47.39±6.01)%显著下降(t=0.000,P＜0.05),APP/PS1小鼠在目标象限中航行路程占总路程的百分比(28.85±3.77)%较WT小鼠(46.70±5.60)%也显著下降(t=0.000,P＜0.05),提示APP/PS1小鼠的空间记忆功能较WT小鼠显著下降.2组小鼠脑组织中的MDA含量、SOD和GSH-PX活性均无明显差异(P均＞0.05),而APP/PS1小鼠脑组织中的蛋白质羰基含量(2.67±0.19)较WT小鼠(2.38±0.15)显著增加(t=0.0088,P＜0.05).相关性分析表明:APP/PS1小鼠蛋白质羰基含量与目标象限航行时间百分比呈显著负性相关(r=-0.639,P＜0.05),APP/PS1小鼠蛋白质羰基含量与目标象限航行路程百分比呈显著负性相关(r=-0.636,P＜0.05).结论 APP/PS1小鼠早期空间记忆功能损害与脑组织中的蛋白质羰基含量升高呈负性相关,提示氧化应激导致的蛋白质羰基化在AD早期记忆损害发病过程中具有重要作用.

Abstract：

Objective To investigate the spatial learning and memory ability,the changes of indicators of oxidative stress,and their relationship in transgenic APP/PS1 mouse model of Alzheimer's disease(APP/PS1 mice). Methods The spatial learning and memory ability were assessed by Morris water maze test,and the activity or content of SOD, GSH-PX, MDA, and protein carbonyl in brain tissues were measured by ELISA in the APP/PS1 and wild type (WT) mice. Furthermore, the relationship between the learning and memory performances and the indicators of oxidative stress was examined. Results No significant difference in the spatial learning was observed between the APP/PS1 and WT mice (P ＜0. 05). The spatial memory which was measured as the percentage of time traveling in the targeted quadrant to the total traveling time was significantlydeclined in the APP/PS1 mice(29. 02 ± 4. 27) % as compared with the WT mice(47. 39 ± 6. 01) %(t =0. 000 ,P ＜0. 05). The percentage of length of traveling in the targeted quadrant to the total length traveled was significantly lower in the APP/PS1 mice(28. 85 ±3.77)% compared with the WT mice(46. 70 ±5.60)% (t =0. 000,P ＜0. 05). These findings indicated that the spatial learning and memory ability of APP/PS1 mice was significantly decreased compared to WT mice. There was no significant difference in activity or content of SOD,GSH-PX,and MDA in brain tissues between the APP/PS1 and WT mice (P ＜ 0. 05), while the content of protein carbonyl was significantly elevated in the APP/PS1 mice (2. 67 ±0. 19) than in the WT mice (2. 38 ±0. 15)(t = 0. 008, P ＜ 0. 05). Correlation analysis revealed that the elevated protein carbonyl was negatively correlated with the percentage of length traveled in the targeted quadrant(r = - 0. 639, P ＜ 0. 05) and the percentage of time traveled in the targeted quadrant(r = - 0. 636 ,P ＜ 0. 05). Conclusion The spatial memory impairment was negatively correlated with the elevated protein carbonyl in the APP/PS1 mice, suggesting that protein carbonylation caused by oxidative stress might play an important role in the development of memory impairment in the early stage of Alzheimer's disease.     

阿尔茨海默病转基因小鼠早期记忆功能障碍与氧化应激损伤关系的实验研究

Objective To investigate the spatial learning and memory ability,the changes of indicators of oxidative stress,and their relationship in transgenic APP/PS1 mouse model of Alzheimer's disease(APP/PS1 mice). Methods The spatial learning and memory ability were assessed by Morris water maze test,and the activity or content of SOD, GSH-PX, MDA, and protein carbonyl in brain tissues were measured by ELISA in the APP/PS1 and wild type (WT) mice. Furthermore, the relationship between the learning and memory performances and the indicators of oxidative stress was examined. Results No significant difference in the spatial learning was observed between the APP/PS1 and WT mice (P ＜0. 05). The spatial memory which was measured as the percentage of time traveling in the targeted quadrant to the total traveling time was significantlydeclined in the APP/PS1 mice(29. 02 ± 4. 27) % as compared with the WT mice(47. 39 ± 6. 01) %(t =0. 000 ,P ＜0. 05). The percentage of length of traveling in the targeted quadrant to the total length traveled was significantly lower in the APP/PS1 mice(28. 85 ±3.77)% compared with the WT mice(46. 70 ±5.60)% (t =0. 000,P ＜0. 05). These findings indicated that the spatial learning and memory ability of APP/PS1 mice was significantly decreased compared to WT mice. There was no significant difference in activity or content of SOD,GSH-PX,and MDA in brain tissues between the APP/PS1 and WT mice (P ＜ 0. 05), while the content of protein carbonyl was significantly elevated in the APP/PS1 mice (2. 67 ±0. 19) than in the WT mice (2. 38 ±0. 15)(t = 0. 008, P ＜ 0. 05). Correlation analysis revealed that the elevated protein carbonyl was negatively correlated with the percentage of length traveled in the targeted quadrant(r = - 0. 639, P ＜ 0. 05) and the percentage of time traveled in the targeted quadrant(r = - 0. 636 ,P ＜ 0. 05). Conclusion The spatial memory impairment was negatively correlated with the elevated protein carbonyl in the APP/PS1 mice, suggesting that protein carbonylation caused by oxidative stress might play an important role in the development of memory impairment in the early stage of Alzheimer's disease.     

乙型肝炎病毒转基因小鼠中外源基因整合的检测

目的了解乙型肝炎病毒DNA序列在乙型肝炎病毒转基因小鼠中的整合情况。方法用头尾相接的乙型肝炎病毒全序列基因,通过原核显微注射法产生转基因小鼠,用C区特异性引物扩增鼠尾DNA检测整合,对其中10只阳性鼠的扩增产物测序。结果128只仔鼠中,14只整合阳性。对10只阳性鼠测序,9只与所转基因序列完全相同,1只在1739、1740位缺失两个碱基。结论外源乙型肝炎病毒基因确定整合至小鼠基因组,多数为正常整合,但也存在缺失整合。     

转基因阿尔茨海默病小鼠脑内炎症反应的诱发因素研究

目的 观察炎症反应在转基因阿尔茨海默病(AD)小鼠脑组织中的变化,探讨AD脑内炎症反应的诱发因素.方法 选用3、12个月龄转人β-淀粉样前体蛋白/早老素-1(APP/PS1)基因AD小鼠及正常野生型(WT)小鼠,分别应用免疫组织化学法和ELISA法观察脑内淀粉样斑块、炎性因子[白细胞介素(IL)-1β、IL-6、肿瘤坏死因子(TNF)α、前列腺素(PGE)2]的变化.结果 3个月龄APP/PS1基因AD小鼠脑组织中无淀粉样斑块沉积,未发现激活的星型胶质细胞和小胶质细胞,炎性因子IL-1β、IL-6、TNFα、PGE2的含量与WT小鼠差异无统计学意义(P均＞0.05).12个月龄转APP/PS1基因AD小鼠脑组织中有大量淀粉样斑块沉积,并伴有大量激活的星型胶质细胞和小胶质细胞,炎性因子IL-1β、IL-6、TNFα、PGE2的含量[分别为(56.02±9.04)、(8.66±0.83)、(97.48±26.58)、(72.18±21.01)ng/g]较WT小鼠[分别为(29.81±6.03)、(7.73±0.74)、(61.98±11.11)、(37.23±10.96)ng/g]及3个月龄转APP/PS1基因AD小鼠[分别为(30.05±3.53)、(7.43±1.17)、(59.34±10.47)、(42.56±5.93)ng/g]显著增加(P＜0.05或P＜0.01).结论 在淀粉样斑块形成之前,转APP/PS1基因AD小鼠脑组织中无明确的炎症反应;而淀粉样斑块沉积之后,脑组织中有显著的炎症反应;AD脑内炎症反应与淀粉样斑块形成密切相关,淀粉样蛋白(Aβ)沉积是导致脑内炎症反应的直接诱发因素.

Abstract：

Objective To observe the changes of cerebral inflammation-related markers in brain of a transgenic mouse model of Alzheimer's disease (AD) ,and to determine the causative factor to the development of cerebral inflammation in AD. Methods 3- and 12-month-old β-amyloid protein precursor ( APP)/presenilin (PSI) transgenic mice and age-matched wild-type mice (WT) were used in the study. The changes of amyloid plaques, inflammatory factors ( interleukin 1β ( IL-1β ); interleukin 6( IL-6 ); tumor necrosis factor α (TNFα) ;prostaglandin E2 (PGE2)) in the brains among these mice were measured by immunohistochemistry and ELISA. Results Immunohistochemical analysis revealed that no amyloid plaques and activated astrocytes as well as microglia were observed in the 3-month-old APP/PS1 mice. There were no significant differences in the levels of inflammatory factors (IL-1β, IL-6 ,TNFα,and PGE2) between the 3-month-old APP/PS1 and WT mice ( Ps ＞ 0. 05 ). However, abundant amyloid plaques accompanied by a remarkable increase of activated astrocytes and microglia were found in the brain of the 12-month-old APP/PS1 mice. The levels of inflammatory factors (IL-1β,IL-6,TNFα, and PGE2 ) were significantly increased in the 12-month-old APP/PS1 mice ([56. 02 ±9. 04] ng/g, [8. 66 ±0.83] ng/g, [97.48 ±26.58] ng/g, [72. 18 ±21.01] ng/g) than in the WT mice ([29. 18 ± 6. 03] ng/g, [7. 73 ± 0. 74] ng/g, [61.98 ±11.11] ng/g, [37. 23 ± 10. 96] ng/g) and the 3-month-old APP/PS1 mice ( [30. 05 ± 3.53] ng/g, [7.43 ± 1.17] ng/g, [59.34 ± 10. 07] ng/g, [42. 56 ±5.93] ng/g) (P＜0.05,or P＜0.01,respectively). Conclusion This study demonstrates that the APP/PS1mice did not show cerebral inflammation before the appearance of amyloid plaques, and exhibited remarkable inflammation after amyloid plaque deposition. These findings suggest that the induction of cerebral inflammation is tightly associated with amyloid plaque formation, and deposition of amyloid-beta protein (Aβ) may be the direct causative factor to the development of cerebral inflammation in AD.     

铁在阿尔茨海默病APPswe／PSl△E9双转基因小鼠模型脑组织内的沉积

目的：研究铁在阿尔茨海默病（AD）APPswe／PSl△E9转基因小鼠脑区中的沉积情况以及与老年斑的对应关系，并探讨铁在AD发病机制中的作用。方法：将PCR鉴定为阳性的APPswe／S1△AE双转基因4及8月龄小鼠为实验组，通过ThioflavineS，Perl’s—DAB，Aβ免疫组化染色，观察铁在脑组织中的沉积并与同月龄野生型小鼠（对照组）对照比较。结果：实验组小鼠基底神经节处均见到铁的沉积，在皮质及海马处呈棕褐色沉积，其分布与老年斑的分布相类似；而对照组小鼠的皮质及海马未见铁的沉积。结论：脑内过多铁的沉积可能是Aβ蛋白在脑内聚集，从而形成老年斑的原因之一，提示铁螯合剂疗法有可能成为治疗AD的一个新的靶点。     

短波辐射对HBV转基因小鼠树突状细胞功能的影响

目的 通过观察短波辐射对HBV转基因小鼠树突状细胞（DC）分泌白介素-12（IL-12）及T淋巴细胞分泌IL-10、IFN-1的影响，从而探讨短波辐射治疗慢性乙型肝炎的可能相关机制。方法 选取HBV转基因小鼠20只，将其随机分为短波组和空白对照组，另取10只健康小鼠作为正常对照组，其中短波组小鼠给予短波辐射。各组小鼠分别于实验进行10d后取其脾脏分离树突状细胞，经流式细胞仪检测DC表型，采用ELISA方法检测DC分泌IL-12以及在刺激混合淋巴细胞反应中T淋巴细胞分泌IL-10、IFN-1的含量变化情况。结果 短波组DC分泌IL-12水平较空白对照组显著增高（P〈0．01）。与正常对照组比较，差异亦有统计学意义（P〈0．01）；在混合淋巴细胞反应中，短波辐射能显著抑制T淋巴细胞分泌IL-10（P〈0．01），并同时提高IFN-1水平（P〈0．01）。结论 短波辐射能显著上调HBV转基因小鼠DC功能，对HBV所致慢性乙型肝炎的临床治疗具有潜在应用价值。     

Peripheral transgene expression of plasma gelsolin reduces amyloid in transgenic mouse models of Alzheimer's disease.

The accumulation and deposition of the 40-42-amino acid peptide amyloid beta (Abeta) is thought to be a critical event in the pathology of Alzheimer's disease (AD). Both passive and active immunizations against Abeta in amyloid-depositing transgenic mice have reduced Abeta pathology and improved memory-related behavior. Peripheral treatments with other amyloid-binding agents have also reduced Abeta pathology. The present study demonstrates that peripheral delivery of plasmid DNA coding for the amyloid-binding protein plasma gelsolin reduces brain Abeta in two separate amyloid-depositing transgenic mouse models of AD when inter-litter variability is accounted for. The reduction in Abeta pathology observed is accompanied by an apparent increase in activated and reactive microglia and soluble oligomeric forms of amyloid. These findings demonstrate that peripheral expression of plasma gelsolin may be a suitable gene-therapeutic approach for the prevention or treatment of AD.     

不同频率和强度超声波溶栓效果的体外实验

目的探讨体外实验条件下超声频率和强度对其溶栓效率的影响。方法取健康人全血标本56份,37℃恒温水浴孵育2h后形成体外血栓。样本被分为5个辐照组和1个对照组。辐照组分别以0．7W／cm^2,0．5MHz;0．7W／cm^2,1MHz;0．7W／cm^2,2MHz;1．4W／cm^2,2MHz和1．8W／cm^2,2MHz的脉冲式超声波照射10min;对照组无超声处理。计算血栓溶栓率,比较各相同声强不同频率组之间差异和相同频率不同声强组之间差异,并分别测溶栓率与超声波频率及强度之间的关系。结果声强0．7W／cm^2条件下,频率为0．5MHz、1MHz和2MHz的超声波有明确的溶栓效果,溶栓率与频率呈负相关（r1=1．000,P〈0．01）;频率2MHz条件下,声强为0．7W／cm^2、1．4W／cm^2和1．8W／cm^2的超声波有明确效果,溶栓率与声强呈正相关（r2=0．980,P〈0．05）。结论在一定条件下,超声波有明确的直接溶栓效果,并与频率和声强相关。诊断用超声波（频率2MHz、声强〈2W／cm^2）可能具有潜在的溶栓价值。     

The use of topical anaesthesia at children's minor lacerations: an experimental study

BACKGROUND: In a great many situations within health care and treatment, children are subjected to unnecessary pain and suffering. When local anaesthetics is to be administered the child can experience this as incomprehensible especially when the nursing staff assures the child that no pain would be felt, only to discover soon after, that it actually did hurt at the moment of anaesthetic infiltration. The soothing of pain during the suturing of wounds in emergency wards can be reduced, ensuring that unnecessary pain in the cafe-and-treatment process is mot meted out to children. In order to prevent this (subjection to unnecessary pain), and by improving accepted practice, it was interesting to investigate whether children felt pain at the time of infiltration anaesthesia following the initial topical anaesthesia. AIM: The aim of the present study was to investigate the effects of introductory topical anaesthesia using Xylocain solution dropped in the wound prior to a definitive infiltration-anaesthesia. An experimental, prospective design was used where children were included in either an experimental group or a control group. The experimental group (n=10) were given a Xylocain solution while the control group (n=10) received physiological Sodium solution. Data collection for the study was made by making VAS estimates and by interviews. RESULT: The study shows that a certain alleviation of pain does occur when using Xylocain but no statistically significant difference exists between the two groups. Irrespective of whether the children received an introductory topical anaesthesia with Xylocain or Sodium solution at the time of infiltration anaesthesia, they expressed pain in connection with infiltration. The study also shows that many children express fear and anxiety. CONCLUSION: Current research highlights the difficulties involved in offering children a really satisfactory form of pain relief in connection with infiltration anaesthesia and suturing of wounds. It is urgent to throw more light on children's pain, both from a nursing and from a medical point of view. No statistically significant difference was found in children's reported pain, after treatment with Xylocain but the solution can have a positive effect at the time of the infiltration jab, but a larger study needs to be done in order to establish this firmly.     

不锈钢圈栓塞效果实验研究

目的：通过Beagle犬胃十二指肠动脉栓塞实验追踪观察并分析不锈钢圈栓塞效果。方法：Beagle犬共18只经股动脉作胃十二指肠动脉插管并用不锈钢圈栓塞,4周后造影复查,其中9只犬用不锈钢圈再次栓塞,所有犬继续追踪4周复查。结果：除一只犬外,所有不锈钢栓塞部位均再通。结论：动脉造影追踪4周,不锈钢圈对犬胃十二指肠动脉几乎无栓塞作用,再次栓塞作用也非常有限。     

Antimicrobial-coated endotracheal tubes: an experimental study

OBJECTIVE: Antibiotic-resistant bacterial biofilm may quickly form on endotracheal tubes (ETTs) and can enter the lungs, potentially causing pneumonia. In an attempt to prevent bacterial colonization, we developed and tested in an in-vitro study and animal study several antibacterial-coated ETTs (silver sulfadiazine with and without carbon in polyurethane, silver sulfadiazine and chlorhexidine with and without carbon in polyurethane, silver-platinum with and without carbon in polyurethane, chlorhexidine in polyurethane, and rose bengal for UV light). DESIGN, SETTING, ANIMALS, INTERVENTIONS: After preliminary studies, silver sulfadiazine in polyurethane (SSD-ETT) was selected among the coatings to be challenged every 24 h with 10(4)-10(6) Pseudomonas aeruginosa/ml and evaluated at 6 h, 24 h, and 72 h with standard microbiological studies, scanning electron microscopy, and confocal scanning microscopy. Subsequently, eight sheep were randomized to receive either a SSD-ETT or a standard ETT (St-ETT). After 24 h of mechanical ventilation, standard microbiological studies were performed together with scanning electron microscopy and confocal microscopy. MEASUREMENTS AND RESULTS: In the in-vitro study SSD-ETT remained bacteria-free for up to 72 h, whereas St-ETT showed heavy P. aeruginosa growth and biofilm formation (p < 0.01). In sheep, the SSD-ETT group showed no bacterial growth in the ETT, ventilator tubing, and lower respiratory tract, while heavy colonization was found in the St-ETT (p < 0.01), ventilator tubing (p=0.03), and lower respiratory tract (p < 0.01). CONCLUSION: This study describes several effective and durable antibacterial coatings for ETTs. Particularly, SSD-ETT showed prevention against P. aeruginosa biofilm formation in a 72-h in-vitro study and lower respiratory tract colonization in sheep mechanically ventilated for 24 h.     

Chemotherapy delays progression of motor neuron disease in the SOD1 G93A transgenic mouse

BACKGROUND: A significant proliferation of glial cells occurs in the spinal cord and brainstem of SOD1 G93A transgenic mice with familial amyotrophic lateral sclerosis (ALS). Since activated glia may contribute to motor neuron degeneration, we tested whether inhibition of gliosis using low-dose chemotherapy is beneficial in this mouse model. METHODS: Mice were administered fortnightly intraperitoneal injections of 0.1 mg/kg vincristine (VIN) or saline commencing at postnatal day 68 before disease onset. Mice were sacrificed at end-stage disease, and spinal cords were examined for histology. RESULTS: Survival of VIN-treated mice was significantly increased at 132.0 +/- 4.1 days compared to control animals at 117.8 +/- 2.1 days (p < 0.05). Furthermore, analysis of microglia and astrocyte populations suggests a reduction in the former following VIN therapy. CONCLUSION: This study suggests that chemotherapy may offer an alternative therapy or co-therapy for ALS.     

Recanalization of experimental thrombotic arterial occlusion by radiofrequency thermal angioplasty: an angioscopic observation

The efficacy of radiofrequency (RF) angioplasty for recanalization of arterial thrombosis was assessed angioscopically in five dogs. A thrombus was induced by balloon injury of the left femoral artery. Within two hr, thrombi led to total occlusion of the artery in three dogs, subtotal occlusion in one, and about 70% obstruction in one. A metal-tipped catheter, with a tip size of 2.0 mm x 5.7 mm, was advanced into the thrombus and RF at 13.56 MHz was delivered repeatedly with gradually increased energies. The arterial lumina were recanalized or enlarged in all dogs. The thrombus surface had a shaggy appearance, and were dark (charring), or mixed dark and white in color. There were relatively large variations in the energies required; 140 J in one, 200 J in two and 250 J in two. The present results suggest that thrombotic arterial occlusion, such as acute occlusion complicating balloon angioplasty, can be treated with RF thermal angioplasty. Angioscopy provided detailed information about thrombus surfaces. The variations in required energies indicate the inability to control the thermal effect by energy settings alone. A more sophisticated method such as measurement of tip temperature will be able to overcome this difficulty.