This study aims to explore the effects of heat and cold stress on the radial pressure pulse (RPP) and heart rate variability (HRV). The subjects immersed their left hand into 45°C and 7°C water for 2 minutes. Sixty healthy subjects (age 25 ± 4 yr; 29 men and 31 women) were enrolled in this study. All subjects underwent the supine temperature measurements of the bilateral forearms, brachial arterial blood pressure, HRV and RPP with a pulse analyzer in normothermic conditions, and thermal stresses. The power spectral low-frequency (LF) and high-frequency (HF) components of HRV decreased in the heat test and increased in the cold test. The heat stress significantly reduced radial augmentation index (AIr) (P < .05), but the cold stress significantly increased AIr (P < .01). The spectral energy of RPP did not show any statistical difference in 0 ~ 10 Hz region under both conditions, but in the region of 10 ~ 50 Hz, there was a significant increase (P < .01) in the heat test and a significant decrease in the cold test (P < .01). The changes in AIr induced by heat and cold stress were significantly negatively correlated with the spectral energy in the region of 10 ~ 50 Hz (SE(10-50 Hz)) but not in the region of 0 ~ 10 Hz (SE(0-10 Hz)). The results demonstrated that the SE(10-50 Hz), which only possessed a small percentage in total pulse energy, presented more physiological characteristics than the SE(0-10 Hz) under the thermal stresses.
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http://dx.doi.org/10.1155/2011/751317 | DOI Listing |
BMC Plant Biol
December 2024
Henan Key Laboratory of Rare Diseases, Endocrinology and Metabolism Center, The First Affiliated Hospital, College of Clinical Medicine of Henan, University of Science and Technology, Luoyang, 471003, China.
PLATZ (plant A/T-rich protein and zinc-binding protein) transcription factors are essential for plant growth, development, and responses to abiotic stress. The regulatory role of PLATZ genes in the environmental adaptation of D. huoshanense is inadequately comprehended.
View Article and Find Full Text PDFPlant Physiol Biochem
December 2024
College of Grassland Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China. Electronic address:
Drought and cold crucially affect plant growth and distribution. Plants have evolved complex molecular mechanisms to adapt to such adverse environmental conditions. This study examines two Elymus sibiricus (Es) germplasms differing in resilience to these stresses.
View Article and Find Full Text PDFNeuroscience
December 2024
Guangdong Provincial Key Laboratory of Animal Nutrition Control, South China Agricultural University, Guangzhou, Guangdong 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong 510642, China. Electronic address:
Corticotropin-releasing factor (CRF) is an important stress hormone, and because of the different distributions and functions of its receptors, CRF has various effects on the stress response of animals. CRF receptor 2 (CRFR2) is functional receptor of CRF that may be related to appetite regulation and sex differences. In this study, male and female C57BL/6 mice were exposed to an ambient temperature of 4 °C, and feed intake were determined.
View Article and Find Full Text PDFSci Rep
December 2024
National & Local United Engineering Laboratory for Chinese Herbal Medicine Breeding and Cultivation, School of Life Sciences, Jilin University, Changchun, Jilin Province, People's Republic of China.
Cold stress, a major abiotic factor, positively modulates the synthesis of artemisinin in Artemisia annua and influences the biosynthesis of other secondary metabolites. To elucidate the changes in the synthesis of secondary metabolites under low-temperature conditions, we conducted dynamic transcriptomic and metabolite quantification analyses of A. annua leaves.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
Plant Fiber Material Science Research Center, State Key Laboratory of Pulp and Paper Engineering, School of Light Industry and Engineering, South China University of Technology, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangzhou 510640, PR China.
The development of flexible, intelligent, and lightweight optoelectronic devices based on flexible transparent conductive electrodes (FTCEs) utilizing silver nanowires (AgNWs) has garnered increasing attention. However, achieving low surface resistance, strong adhesion to the flexible substrate, low surface roughness, and green degradability remains a challenge. Here, a composite electrode combining natural polymer cellulose nanofibers (TCNFs) with AgNWs was prepared.
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