Mechanism underlying the influence of humidity on thermal comfort and stress under mimicked working conditions.

Thermal comfort in an office impacts physical health, stress, and productivity. Humidity affects thermal comfort; however, the underlying mechanism remains unclear. This study assessed the influence of humidity on body temperature, thermal comfort, stress, and their relationship in working individuals.

Influence of sustained mild dehydration on thermoregulatory and cognitive functions during prolonged moderate exercise.

Purpose: The current study investigated whether sustained mild dehydration affects thermoregulatory function and cognitive performance during prolonged exercise.

Methods: Twelve young adults performed a test consisting of three sets of 20-min exercise with 2-min intervals under euhydrated (control, CON) and mildly dehydrated conditions (MDEH) at an ambient temperature of 30 °C and 60% relative humidity. MDEH was established by restricting water intake for 24 h, resulting in urine specific gravity of ≥ 1.

Evaluation of newly developed wearable ear canal thermometer, mimicking the application to activities on sports and labor fields.

We evaluated the reliability of a newly developed wearable ear canal thermometer based on three different experiments, in which ear canal and rectal temperature (T and T, respectively) were simultaneously monitored. In Experiment 1, participants sat at 28 °C and 50% relative humidity (RH), during which fanning or 41 °C lower legs water immersion was conducted. In Experiment 2, participants conducted a 70-min treadmill exercise (4 km/h, 0.

Characteristics of wet perception during the static touch of moist paper by the index fingertip alongside thermal stimulus application.

Several factors have been reported to affect the perception of wetness. In the present study, we aimed to examine how wet perception changes when the factors related to thermal and/or wetness stimuli are modulated. First, the percentage of participants experiencing wet perception among filter papers with different water contents (0.

Thermoregulatory heat-escape/cold-seeking behavior in mice and the influence of TRPV1 channels.

The present study assessed heat-escape/cold-seeking behavior during thermoregulation in mice and the influence of TRPV1 channels. Mice received subcutaneous injection of capsaicin (50 mg/kg; CAP group) for desensitization of TRPV1 channels or vehicle (control [CON] group). In Experiment 1, heat-escape/cold-seeking behavior was assessed using a newly developed system comprising five temperature-controlled boards placed in a cross-shape.

Differences in the neural networks of thermal sensation with and without evaluation process.

Several neuroimaging studies have analyzed the neural networks involved in thermal sensation. In some of these studies, participants were instructed to evaluate and report the thermal sensation using a point scale, visual analog scale, or other psychophysical rating tool while the imaging data were obtained. Therefore, the imaging data may reflect signals involved in the processes of both sensation and evaluation.

Surgical masks do not increase the risk of heat stroke during mild exercise in hot and humid environment.

Surgical masks are widely used for the prevention of respiratory infections. However, the risk of heat stroke during intense work or exercise in hot and humid environment is a concern. This study aimed to examine whether wearing a surgical mask increases the risk of heat stroke during mild exercise in such environment.

Regular exercise stimulates endothelium autophagy via IL-1 signaling in ApoE deficient mice.

Regular exercise maintains arterial endothelial cell homeostasis and protects the arteries from vascular disease, such as peripheral artery disease and atherosclerosis. Autophagy, which is a cellular process that degrades misfolded or aggregate proteins and damaged organelles, plays an important role in maintaining organ and cellular homeostasis. However, it is unknown whether regular exercise stimulates autophagy in aorta endothelial cells of mice prone to atherosclerosis independently of their circulating lipid profile.

Influence of exogenous and endogenous estrogen on thermoregulatory responses to mild heat and the interaction with light and dark phases.

The present study aimed to determine the influence of estradiol (E) and the interaction with circadian phases on thermoregulatory responses to mild heat in female rats. Heat loss and production during 3-h exposure to the environment at an ambient temperature of 28-34 °C were assessed by measuring abdominal temperature (T), tail skin temperature, and oxygen consumption in ovariectomized rats with and without E replacement (OVX + E and OVX, respectively) and in control rats in the proestrus (P) and diestrus (D) phases. In the light phase, T remained unchanged in all groups.

Muscle-derived SDF-1α/CXCL12 modulates endothelial cell proliferation but not exercise training-induced angiogenesis.

Chemokines are critical mediators of angiogenesis in several physiological and pathological conditions; however, a potential role for muscle-derived chemokines in exercise-stimulated angiogenesis in skeletal muscle remains poorly understood. Here, we postulated that the chemokine stromal cell-derived factor-1 (SDF-1α/C-X-C motif chemokine ligand 12: CXCL12), shown to promote neovascularization in several organs, contributes to angiogenesis in skeletal muscle. We found that CXCL12 is abundantly expressed in capillary-rich oxidative soleus and exercise-trained plantaris muscles.

Thermal and cardiovascular responses and thermal sensation during hot-water bathing and the influence of room temperature.

The aim of the present study was to clarify physical risks during hot-water bathing by measuring thermal and cardiovascular responses and thermal sensation. Young men and women (n = 7 and 5, respectively) participated in the present study, which consisted of two trials mimicking bathing behavior at room temperature of 25 °C and 15 °C. Participants bathed in 41 °C water for 20 min to the subclavian level.

Assessment of brain mechanisms involved in the processes of thermal sensation, pleasantness/unpleasantness, and evaluation.

The conscious perception of thermal stimuli is divided into two categories: thermal sensation (i.e., discriminative component) and pleasantness/unpleasantness (i.

Thermal comfort.

The processes of thermoregulation are roughly divided into two categories: autonomic and behavioral. Behavioral thermoregulation alone does not have the capacity to regulate core temperature, as autonomic thermoregulation. However, behavioral thermoregulation is often utilized to maintain core temperature in a normal environment and is critical for surviving extreme environments.

Fasting or systemic des-acyl ghrelin administration to rats facilitates thermoregulatory behavior in a cold environment.

Fasted rats place their tails underneath their body trunks in the cold (tail-hiding behavior), which is a thermoregulatory behavior. The aim of the present study was to investigate the effect of fasting and des-acyl ghrelin, a hormone related to fasting, on tail-hiding behavior and neural activity in the cold. Wistar rats were divided into 'fed', '42-h fasting' and des-acyl ghrelin groups.

Regional differences of cFos immunoreactive cells in the preoptic areas in hypothalamus associated with heat and cold responses in mice.

cFos expression in the preoptic area (PO), which is thermoregulatory center increased by both heat and cold exposures; however, the regional difference is unknown yet. We aimed to determine if cFos expression in the PO was regionally different between heat and cold exposures. Mice were exposed to 27, 10, or 38°C for 90min, and body temperature (T) was measured.

Body temperature and cold sensation during and following exercise under temperate room conditions in cold-sensitive young trained females.

We evaluated cold sensation at rest and in response to exercise-induced changes in core and skin temperatures in cold-sensitive exercise trained females. Fifty-eight trained young females were screened by a questionnaire, selecting cold-sensitive (Cold-sensitive,  = 7) and non-cold-sensitive (Control,  = 7) individuals. Participants rested in a room at 29.

Systemic estradiol administration to ovariectomized rats facilitates thermoregulatory behavior in a cold environment.

Rats place their tails underneath their bodies in the cold (tail-hiding behavior), which is a behavioral indicator of thermoregulation. The aim of the present study was to elucidate the effect of estradiol (E) on tail-hiding behavior and neural activity assessed by immunohistochemistry. Ovariectomized rats were implanted with a silastic tube with or without E underneath the dorsal skin (E(-) and E(+) groups), and exposed to 27°C, 16°C, and 10°C for 2h with continuous body temperature (T), tail skin temperature (T), and behavioral measurements.

Assessment of axillary temperature for the evaluation of normal body temperature of healthy young adults at rest in a thermoneutral environment.

Background: The aims of this study were to (1) evaluate whether recently introduced methods of measuring axillary temperature are reliable, (2) examine if individuals know their baseline body temperature based on an actual measurement, and (3) assess the factors affecting axillary temperature and reevaluate the meaning of the axillary temperature.

Methods: Subjects were healthy young men and women (n = 76 and n = 65, respectively). Three measurements were obtained: (1) axillary temperature using a digital thermometer in a predictive mode requiring 10 s (T ), (2) axillary temperature using a digital thermometer in a standard mode requiring 10 min (T ), and (3) tympanic membrane temperature continuously measured by infrared thermometry (T ).

Influence of osmotic stress on thermal perception and thermoregulation in heat is different between sedentary and trained men.

Hyperosmolality in extracellular fluid in humans attenuates autonomic thermoregulation in heat, such as sweating and blood flow in the skin. However, exercise training minimizes the attenuation. The aim of the present study was to clarify the influence of hyperosmolality on thermal perception and to assess the training effect of exercise.

Cold exposure and/or fasting modulate the relationship between sleep and body temperature rhythms in mice.

We assessed the relationship between core temperature (Tc) and sleep rhythms in mice, and examined the effects of ambient temperature and fasting. Tc, electroencephalograms (EEG), electromyograms (EMG), and spontaneous activity in male ICR mice (n=9) were measured by telemetry for 3 days under a 12:12h dark-light cycle. Mice were fed or fasted at an ambient temperature (Ta) of 27°C or 20°C for the final 30h of the experiment.

Estimation of the core temperature control during ambient temperature changes and the influence of circadian rhythm and metabolic conditions in mice.

It has been speculated that the control of core temperature is modulated by physiological demands. We could not prove the modulation because we did not have a good method to evaluate the control. In the present study, the control of core temperature in mice was assessed by exposing them to various ambient temperatures (Ta), and the influence of circadian rhythm and feeding condition was evaluated.