O'Hara M D, Arnold S B, Rowley R, Leeper D B
Department of Radiation Oncology and Nuclear Medicine, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania 19107.
Int J Hyperthermia. 1989 Sep-Oct;5(5):589-601. doi: 10.3109/02656738909140483.
The method used to restrain anaesthetized (sodium pentobarbital) mice for in situ heating of tibial marrow affects the survival response of CFU-GM. Three methods of limb restraint, in addition to ischaemia induced by tourniquet, were examined for their relative effect on the thermal response of CFU-GM. The three methods of restraint were to secure only the toes with suture material to a submersion post in the water bath, to tape the foot, or to tape the leg. Temperatures in the lumen of the tibia were measured with a 100 micron (tip diameter) microthermocouple during representative experimental conditions. After heating in situ, bone marrow was extruded and CFU-GM cultured in standard soft agar conditions in lung-conditioned medium. The most restrictive restraining method, i.e. taping the leg, produced the greatest thermal response among the three restraining methods examined. The D0 (+/- 95% CI) of the 42 degrees C survival curve for CFU-GM was 22 +/- 4, 46 +/- 8, or 94 +/- 53 min for restraint of leg, foot, or toes, respectively. Survival reached a plateau by 100 min of heating indicative of the development of thermotolerance. The D0 of the 44 degrees C survival curve was 3 +/- 1, 6 +/- 2 and 16 +/- 6 min for restraint of leg, foot, or toes respectively. Ischaemia produced the most pronounced effect on the thermal response of tibial CFU-GM with D0 values of 2 +/- 1 or 3.6 +/- 1.5 min after exposure to 44 degrees C or 42 degrees C, respectively. The method of limb restraint affects the thermal sensitivity of CFU-GM most probably by blood flow obstruction and resultant pH decrease. Thus, precautions must be taken to ensure that limb restriction does not introduce artifacts in the hyperthermia response of normal tissues or tumours during heating in situ.
用于束缚麻醉（戊巴比妥钠）小鼠以对胫骨骨髓进行原位加热的方法会影响CFU - GM的存活反应。除了止血带诱导的缺血外，还检查了三种肢体束缚方法对CFU - GM热反应的相对影响。三种束缚方法分别是用缝合材料仅将脚趾固定在水浴中的浸没柱上、用胶带固定足部或用胶带固定腿部。在代表性实验条件下，用100微米（尖端直径）的微型热电偶测量胫骨管腔内的温度。原位加热后，挤出骨髓并在肺条件培养基中的标准软琼脂条件下培养CFU - GM。在检查的三种束缚方法中，最具限制性的束缚方法，即用胶带固定腿部，产生了最大的热反应。对于CFU - GM，42℃存活曲线的D0（±95%置信区间）在分别束缚腿部、足部或脚趾时为22±4、46±8或94±53分钟。加热100分钟时存活达到平台期，表明热耐受的发展。44℃存活曲线的D0在分别束缚腿部、足部或脚趾时为3±1、6±2和16±6分钟。缺血对胫骨CFU - GM的热反应产生最明显的影响，在分别暴露于44℃或42℃后，D0值为2±1或3.6±1.5分钟。肢体束缚方法很可能通过血流阻塞和随之而来的pH值降低来影响CFU - GM的热敏感性。因此，必须采取预防措施，以确保在原位加热过程中肢体限制不会在正常组织或肿瘤的热疗反应中引入假象。
