• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>International astronautical congress >THERMOREGULATION BY SEX: A CARDIOVASCULAR MRI STUDY
【24h】

THERMOREGULATION BY SEX: A CARDIOVASCULAR MRI STUDY

机译：通过性别进行热调节：心血管MRI研究

获取原文
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Core temperature impacts human performance and health. Humans maintain core temperature via the process of thermoregulation. Thermoregulation is affected by changes in: convective heat transfer from skin to environment, autonomic nervous system and metabolic processes, and cardiovascular (CV) system. The CV system plays a vital role in thermoregulation because of the influence of convection and regulation of regional blood flow. For long space flights, altered thermoregulation could compromise astronaut performance; however, little is known about the impact of sex on CV system responses to core temperature changes. Purpose: To determine sex differences in the cardiovascular system's response to core temperature changes, eventually quantifying tissue thermal properties. A better understanding of the physiological contributors to thermoregulation will aid in astronaut selection, training, and performance. Methodology: Male and female mice were anesthetized and imaged at 7T. Anatomical and functional data included the periphery (femoral, saphenous, popliteal arteries), central nervous system (Circle of Willis, CoW), infrarenal aorta, and heart. Data was acquired at 35, 36, 37, and 38 C. Cross-sectional area of the peripheral and cerebral arteries was calculated using thresholding methods. Infrarenal area and endocardial area across the cardiac cycle were quantified, with the latter used to calculate stroke volume and cardiac output. MR thermometry was implemented to determine temperature changes in the musculature non-invasively. Results and Discussion: Changes due to temperature were largest in the peripheral vessels. Peripheral vessel area in males was statistically larger than females; however, females had a larger percent increase in vessel area. The tracking length increased by 290% in males and 768% in females from 35 to 38C. The CoW area remained the same for each temperature with differences between sexes at 36 and 38C. Infrarenal area increased with increasing temperature. Cardiac output and ejection fraction did not change. However, sex differences occur at all temperatures for both heart and infrarenal aorta. Maps from MR thermometry appear promising, showing relative differences in tissue temperatures. Conclusion: This work is a novel approach to studying thermoregulation by using imaging techniques to quantify functional changes due to altered core temperature. The sex difference between CV responses cannot be attributed to body size difference alone. Future work includes: validating MR thermometry using temperature probes placed in specific tissue compartments (central blood vessel, muscle, skin); quantifying changes in the venous system; and, determining the contribution of body composition, athletic training, age, and the influence of different physiological states, e.g. exercise.
机译：核心温度会影响人类的表现和健康。人类通过温度调节过程维持核心温度。温度调节受以下变化的影响：对流热量从皮肤到环境的传递，自主神经系统和代谢过程以及心血管（CV）系统。由于对流和局部血流调节的影响，CV系统在温度调节中起着至关重要的作用。对于长途飞行，温度调节的改变可能会损害宇航员的表现;然而，关于性别对CV系统对核心温度变化的反应的影响知之甚少。目的：确定心血管系统对核心温度变化的反应中的性别差异，最终量化组织的热特性。更好地了解温度调节的生理因素将有助于宇航员的选择，训练和表现。方法：将雄性和雌性小鼠麻醉并在7T成像。解剖学和功能性数据包括外周（股动脉，隐性动脉，pop动脉），中枢神经系统（Willis圆，CoW），肾下主动脉和心脏。在35、36、37和38 C下获取数据。使用阈值化方法计算外周动脉和脑动脉的横截面积。量化整个心动周期的肾下面积和心内膜面积，后者用于计算中风量和心输出量。 MR测温法可以无创地确定肌肉组织的温度变化。结果与讨论：温度引起的变化在周围血管中最大。统计学上，雄性的外周血管面积大于雌性;但是，女性的船只面积增加的百分比更大。从35°C到38°C，男性的追踪长度增加了290％，而女性则增加了768％。每个温度的CoW面积均保持不变，并且性别在36和38℃之间有所差异。肾下面积随温度升高而增加。心脏输出和射血分数未改变。但是，心脏和肾下主动脉在所有温度下均会发生性别差异。 MR测温法得出的图看起来很有希望，显示出组织温度的相对差异。结论：这项工作是通过使用成像技术来量化由于核心温度变化而引起的功能变化来研究温度调节的一种新颖方法。 CV反应之间的性别差异不能仅归因于体型差异。未来的工作包括：使用放置在特定组织隔室（中央血管，肌肉，皮肤）中的温度探针验证MR测温;量化静脉系统的变化;并且确定身体组成，运动训练，年龄以及不同生理状态的影响的贡献，例如锻炼。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号