Valdez Chris M, Barnes Ronald, Roth Caleb C, Moen Erick, Ibey Bennett
Radio Frequency Bioeffects Branch, Bioeffects Division, Airman Systems Directorate, 711th Human Performance Wing, Air Force Research Laboratory, JBSA Fort Sam Houston, Texas.
Ming Hsieh Department of Electrical Engineering- Electrophysics, University of Southern California, Los Angeles, California.
Bioelectromagnetics. 2018 Sep;39(6):441-450. doi: 10.1002/bem.22134. Epub 2018 Jul 9.
Nanosecond electric pulse (nsEP) exposure generates an array of physiological effects. The extent of these effects is impacted by whether the nsEP is a unipolar (UP) or bipolar (BP) exposure. A 600 ns pulse can generate 71% more YO-PRO-1 uptake compared to a 600 ns + 600 ns pulse exposure. This observation is termed "bipolar cancellation" (BPC) because despite the BP nsEP consisting of an additional 600 ns pulse, it generates reduced membrane perturbation. BPC is achieved by varying pulse amplitudes, and symmetrical and asymmetric pulse widths. The effect appears to reverse by increasing the interphase interval between symmetric BP pulses, suggesting membrane recovery is a BPC factor. To date, the impact of the interphase interval between asymmetrical BP and other BPC-inducing symmetrical BP nsEPs has not been fully explored. Additionally, interpulse intervals beyond 50 μs have not been explored to understand the impact of time between the BP nsEP phases. Here, we surveyed different interphase intervals among symmetrical and asymmetrical BP nsEPs to monitor their impact on BPC of YO-PRO-1 uptake. We identified that a 10 microsecond (ms) interphase interval within a symmetrical 600 ns + 600 ns, and 900 ns + 900 ns pulse can resolve BPC. Furthermore, the interphase interval to resolve asymmetric BPC from a 300 ns + 900 ns pulse versus 600 ns pulse exposure is greater (<10 ms) compared to symmetrical BP nsEPs. From these findings, we extended on our conceptual model that BPC is balanced by localized charging and discharging events across the membrane. Bioelectromagnetics. 39:441-450, 2018. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.
纳秒级电脉冲（nsEP）暴露会产生一系列生理效应。这些效应的程度受到nsEP是单极（UP）暴露还是双极（BP）暴露的影响。与600 ns + 600 ns脉冲暴露相比，600 ns脉冲可使YO-PRO-1摄取增加71%。这一观察结果被称为“双极抵消”（BPC），因为尽管BP nsEP由额外的600 ns脉冲组成，但它产生的膜扰动较小。BPC通过改变脉冲幅度以及对称和不对称脉冲宽度来实现。通过增加对称BP脉冲之间的相间间隔，这种效应似乎会逆转，这表明膜恢复是一个BPC因素。迄今为止，非对称BP与其他诱导BPC的对称BP nsEPs之间的相间间隔的影响尚未得到充分探索。此外，尚未探索超过50 μs的脉冲间隔，以了解BP nsEP各阶段之间的时间影响。在这里，我们研究了对称和非对称BP nsEPs之间不同的相间间隔，以监测它们对YO-PRO-1摄取的BPC的影响。我们发现，在对称的600 ns + 600 ns和900 ns + 900 ns脉冲中，10微秒（ms）的相间间隔可以消除BPC。此外，与对称BP nsEPs相比，从300 ns + 900 ns脉冲与600 ns脉冲暴露中消除非对称BPC的相间间隔更大（<10 ms）。基于这些发现，我们扩展了我们的概念模型，即BPC是由跨膜的局部充电和放电事件平衡的。《生物电磁学》。39:441 - 450，2018年。2018年发表。本文是美国政府作品，在美国属于公共领域。
