Acclimatization ; Altitude ; Electroencephalography ; Humans

Acclimatization ; Acinetobacter ; metabolism ; Cold Temperature ; Transcriptome

OBJECTIVETo analysis deacclimatization symptom scores of 159 youth from Karakoram and Tibet Ali area, and provide the basis for the development of relevant prevention and control measures.

METHODSUsing the method of epidemiological symptoms questionnaire, 18 symptoms of 190 youth who returned to the plain area from the different plateau were investigated. The symptom scores of different altitude, age, the time of staying, different units, continuous or intermittent stage and education were surveyed.

RESULTSDeacclimatization symptom scores among 5,000 meter groups were significantly higher than those of 4,300 meter and 3,700 meter group (P < 0.05, P < 0.01). There was no significant difference between the 4,300 meter group and the 3,700 meter group (P > 0.05). There were significant differences among the stayed personnel (different age, position, unit, education, time, continuous or intermittent) (P < 0.01). There was significant difference between the continuous defended the group and intermittent group (P < 0.01).

CONCLUSIONDeacclimatization symptom scores were related to the plateau exposure time, altitude, workload, plateau continued exposure. The older, the longer exposure, the higher altitude, the greater workload at plateau were showed higher deacclimatization symptom score.

Acclimatization ; Altitude ; Altitude Sickness ; physiopathology ; Humans ; Surveys and Questionnaires ; Tibet

The incidence of deacclimatization to high altitude syndrome (DAHAS) prevailed up to 80% in highland troops, and 100% in manual workers, and severe DAHAS could significantly affects patients' health, work and life. So it is imperative to develop effective prevention and treatment measures for DAHAS. The present review analyzes effective prophylactic and therapeutic measures against DAHAS, implemented at our hospital.
Acclimatization ; Altitude ; Altitude Sickness ; prevention & control ; therapy ; Humans

Acclimatization ; Dizziness ; rehabilitation ; therapy ; Humans ; Vestibulocochlear Nerve ; physiology

The alteration of pulmonary artery pressure is an important physiological indicator to reflect the organism's adaptation to acclimatization or the pathological injury in response to high-altitude hypoxic environment. The effects of hypoxic stress at different altitudes for different time on pulmonary artery pressure are different. There are many factors involved in the changes of pulmonary artery pressure, such as the contraction of pulmonary arterial smooth muscle, hemodynamic changes, abnormal regulation of vascular activity and abnormal changes of cardiopulmonary function. Understanding of the regulatory factors of pulmonary artery pressure in hypoxic environment is crucial in clarifying the relevant mechanisms of hypoxic adaptation, acclimatization, prevention, diagnosis, treatment and prognosis of acute and chronic high-altitude diseases. In recent years, great progress has been made in the study regarding the factors affecting pulmonary artery pressure in response to high-altitude hypoxic stress. In this review, we discuss the regulatory factors and intervention measures of pulmonary arterial hypertension induced by hypoxia from the aspects of hemodynamics of circulatory system, vasoactive state and changes of cardiopulmonary function.
Humans ; Altitude ; Arterial Pressure ; Acclimatization ; Hypoxia ; Muscle, Smooth

OBJECTIVEIncidence and severity of motion sickness (MS) in hot-humid environment are extremely high. We tried to know the effect of two-stage training for reducing incidence and severity of ms.

METHODSSixty male subjects were divided into experimental group and control group randomly. Subjects in experimental group received: (2) adaptation training including sitting, walking and running in hot lab. After adaptation confirmation based on subjective feeling, rectal temperature, heart rate, blood Pressure, sweat rates and sweat salt concentration, we tested both groups by Coriolis acceleration revolving chair test and recorded Graybiel's score and grading of severity to evaluate whether adaptation training was useful; (2) Anti-dizzy training 3m later of deacclimatization contained revolving chair training for 10 times. Then we did the same test as mentioned above to evaluate effect of anti-dizzy training. RESULST: Graybiel' s score and grading of severity had no difference between two groups through acclimatization training (P > 0.05). While they had difference through anti-dizzy training (P < 0.01).

CONCLUSIONAdaptation training seems useless for reducing incidence and severity of MS in hot-humid environment, but anti-dizzy training is useful.

Acclimatization ; physiology ; Adolescent ; Hot Temperature ; Humans ; Male ; Motion Sickness ; physiopathology ; prevention & control ; Young Adult

OBJECTIVETo investigate effects of the variation of immune function in high humidity environment in different time, and lay a foundation for further study of the related mechanism.

METHODThirty SD rats were divided into 3 groups (n = 10): 20 day group, 40 day group in 90% relative humidity chamber and control group in normal relative humidity. Peripheral blood and spleens were collected to detect the levels of T lymphocyte subsets by Flow Cytometery.

RESULTSIn peripheral blood of the 20 day group rats, the CD3+ %, CD4+ %, CD8+ % and CD4+/CD8+ were 52.91 +/- 6.27, 37.80 +/- 4.11, 14.85 +/- 3.73 and 2.72 +/- 0.82 separately. Expect CD3+ %, they all had significant differences (P < 0.05). In addition, the data of the 40 day group rats showed no diversity in statistics. In spleen, CD8+ % of the 20 day group rats was 6.23 +/- 2.87 with significant differences (P < 0.05) and IgG, IgA and IgM did not change a lot in blood serum of the high humidity groups except C3 of the 20 days group (P < 0.05).

CONCLUSIONIn high humidity environment, the immune function of the rats increased in the initial stage. As time went on, the immune function gradually went to normal level through the self adjustment.

Acclimatization ; Animals ; Humidity ; Rats ; Rats, Sprague-Dawley ; Spleen ; immunology ; T-Lymphocyte Subsets ; immunology

OBJECTIVEThis study was aimed to explore the physiological changes and the effect of heat acclimation training via a randomized control trial study.

METHODSForty healthy male volunteers were chosen and divided into experimental group and control group randomly. Those in experimental group received heat acclimation training including but not limited to meditation, unarmed run, yoga, and stepping in hot lab environment. And then, subjective feeling, rectal temperature, average skin temperature, and sweat electrolytes concentration were detected in order to describe their physiological changes. Before and after the training, both groups received some tests and their 3 000 m run-race time, nervous reaction time and subjective perception scores were recorded to evaluate the effect of acclimation training.

RESULTS(1) There was no difference in 3 000 m between the 2 groups in the same environment. Subjects' 3 000 m race time in experimental group was obviously shortened than that in control group in room temperature environment (t = 2.326, P < 0.05). And subjects' 3 000 m race time in experimental group was obviously shortened than that in control group in hot-humid environment (t = 4.518, P < 0.01). (2) Subjects' reaction time (RT) in experimental group was shortened than that in control group in room temperature environment (Z = 11.258, P < 0.05). And Subjects' RT in experimental group was sharply shortened than that in control group in hot-humid environment (Z = 6.519, P < 0.01). (3) No difference between the experimental and control groups was observed in subjective perception score (SPS) in room temperature environment. But subjects' SPS in experimental group was obviously lowered than that in control group and in hot-humid environment (t = 17.958, P < 0.01).(4) Anal temperature (AT) was lowered during training, while the change of mean skin temperature (MST) was not significant. Sweat sodium concentration (SSC) was lowered during training. SPS continued to decrease and entered plateau on the 13th day after training.(5) After acclimation training, the working capacity of the experimental group in hot-humid environment was over 85% of that in room temperature environment. While subjects' working capacity in control group in hot-humid environment was about 80% of that in room temperature environment.

CONCLUSIONHot-humid environment acclimation training improved the working capacity. After training, subjects' working capacity in hot-humid environment remained over 85% of that in room temperature environment, which was higher than that of those subjects who did not take part in training.

Acclimatization ; physiology ; Body Temperature ; Heart Rate ; Hot Temperature ; Humans ; Humidity ; Male ; Physical Conditioning, Human ; physiology ; Sweating

BACKGROUND: The objectives of the present study are to: (i) evaluate the effect of environmental and metabolic heat on heat-related illnesses in outdoor workers; and (ii) evaluate the effect of personal factors, including heat acclimation, on the risk of heat-related illnesses in outdoor workers. METHODS: We identified 47 cases of illnesses from exposure to environmental heat in outdoor workers in Korea from 2010 to 2014, based on review of workers' compensation data. We also obtained the information on location, time, and work environment of each heat-related illness. RESULTS: Our major results are that 29 cases (61.7%) occurred during a heat wave. Forty five cases (95.7%) occurred when the maximum estimated WBGT (WBGTmax) was equal to or greater than the case specific threshold value which was determined by acclimatization and metabolic rate. Twenty two cases (46.8%) were not acclimated to the heat. Thirty-seven cases (78.7%) occurred after tropical night (temperature above 25 °C), during which many people may find it hard to sleep. CONCLUSION: Personal risk factors such as heat acclimation as well as environmental factors and high metabolic rate during work are the major determinants of heat-related illnesses.
Acclimatization ; Extreme Heat* ; Hot Temperature ; Humans ; Infrared Rays ; Korea ; Risk Factors ; Workers' Compensation