Sleep and Temperature / 수면정신생리

Changes in core body temperature are closely related to initiation and maintenance of sleep, and are influenced by various factors such as air temperature, room temperature, clothing, human activities, and medications. These factors are closely related to sleep fragments, insomnia and other sleep disorders. Understanding the effect of the temperature related to human surroundings on the core body temperature and sleep, will be useful for understanding the physiology of sleep and to treat sleep disorders.

Differential susceptibility of BALB/c, C57BL/6N, and CF1 mice to photoperiod changes

Objective:Circadian disturbances common to modern lifestyles have been associated with mood disorders. Animal models that mimic such rhythm disturbances are useful in translational research to explore factors contributing to depressive disorders. This study aimed to verify the susceptibility of BALB/c, C57BL/6N, and CF1 mice to photoperiod changes.Methods:Thermochron iButtons implanted in the mouse abdomen were used to characterize temperature rhythms. Mice were maintained under a 12:12 h light-dark (LD) cycle for 15 days, followed by a 10:10 h LD cycle for 10 days. Cosinor analysis, Rayleigh z test, periodograms, and Fourier analysis were used to analyze rhythm parameters. Paired Student's t test was used to compare temperature amplitude, period, and power of the first harmonic between normal and shortened cycles.Results:The shortened LD cycle significantly changed temperature acrophases and rhythm amplitude in all mouse strains, but only BALB/c showed altered period.Conclusion:These findings suggest that BALB/c, the preferred strain for stress-induced models of depression, should also be favored for exploring the relationship between circadian rhythms and mood. Temperature rhythm proved to be a useful parameter for characterizing rhythm disruption in mice. Although disruption of temperature rhythm has been successfully documented in untethered mice, an evaluation of desynchronization of other rhythms is warranted.

Effect of Lateral Preoptic Area Lesion on Sleep Wakefulness and Thermoregulation In Cold Acclimatized Rats.

Hypothalamic temperature (Thy) alteration is one of the important stimuli that brings about thermoregulatory measures including the changes in wakefulness and muscular activity. The role of the lateral preoptic area (lPOA) in thermoregulation and sleep is well documented. But it is not known whether the integrity of the lPOA is essential for bringing about the changes in sleep-wakefulness (S-W) and thermoregulation in cold ambient temperature (Ta). Neurotoxic lesion of the lPOA resulted in an increase in wake period and core body temperature (Tb) and no change in Thy. Unlike, normal animals, as reported earlier, there was further increase in Tb of the lPOA lesioned rats on acute cold exposure, but the Thy remained unaltered throughout the 28 days of continued cold exposure. The findings demonstrate that the lPOA lesioned rats have lost the ability to reset Thy which may be necessary for thermoregulation during cold exposure. Moreover, increased wake period lasted only 7 days in lesioned, compared to 14 days in normal animals. Less efficient restoration of Tb, and less prolonged wake period during continued cold exposure, are probably the result of the inability of the lPOA lesioned rats to lower Thy, which is necessary to bring about the thermoregulatory measures.

Aminophylline Partially Prevents the Decrease of Body Temperature during Laparoscopic Abdominal Surgery

Aminophylline can elicit thermogenesis in rats or increase metabolic rate during cold stress in lambs. We tested the hypothesis that aminophylline would reduce the change in core body temperature during laparoscopic abdominal surgery requiring pneumoperitoneum. Fifty patients were randomly divided into an aminophylline group (n=25) and a saline control group (n=25). Esophageal temperature, index finger temperature, and hemodynamic variables, such as mean blood pressure and heart rate, were measured every 15 min during sevoflurane anesthesia. In the aminophylline group, esophageal temperatures at T45 (36.1+/-0.38 vs. 35.7+/-0.29, P=0.024), T60 (36.0+/-0.39 vs. 35.6+/-0.28, P=0.053), T75 (35.9+/-0.34 vs. 35.5+/-0.28, P=0.025), T90 (35.8+/-0.35 vs. 35.3+/-0.33, P=0.011), and T105 (35.8+/-0.36 vs. 35.1+/-0.53, P=0.017) and index finger temperatures at T15 (35.8+/-0.46 vs. 34.9+/-0.33, P<0.001), T30 (35.7+/-0.36 vs. 35.0+/-0.58, P=0.029), T45 (35.8+/-0.34 vs. 35.2+/-0.42, P=0.020), T60 (35.7+/-0.33 vs. 34.9+/-0.47, P=0.010), T75 (35.6+/-0.36 vs. 34.8+/-0.67, P=0.028), T90 (35.4+/-0.55 vs. 34.4+/-0.89, P=0.042), and T105 (34.9+/-0.53 vs. 33.9+/-0.85, P=0.024) were significantly higher than in the saline control group. Aminophylline is effective in maintaining the core temperature through a thermogenic effect, despite reduced peripheral thermoregulatory vasoconstriction.

Aminophylline Partially Prevents the Decrease of Body Temperature during Laparoscopic Abdominal Surgery

Aminophylline can elicit thermogenesis in rats or increase metabolic rate during cold stress in lambs. We tested the hypothesis that aminophylline would reduce the change in core body temperature during laparoscopic abdominal surgery requiring pneumoperitoneum. Fifty patients were randomly divided into an aminophylline group (n=25) and a saline control group (n=25). Esophageal temperature, index finger temperature, and hemodynamic variables, such as mean blood pressure and heart rate, were measured every 15 min during sevoflurane anesthesia. In the aminophylline group, esophageal temperatures at T45 (36.1+/-0.38 vs. 35.7+/-0.29, P=0.024), T60 (36.0+/-0.39 vs. 35.6+/-0.28, P=0.053), T75 (35.9+/-0.34 vs. 35.5+/-0.28, P=0.025), T90 (35.8+/-0.35 vs. 35.3+/-0.33, P=0.011), and T105 (35.8+/-0.36 vs. 35.1+/-0.53, P=0.017) and index finger temperatures at T15 (35.8+/-0.46 vs. 34.9+/-0.33, P<0.001), T30 (35.7+/-0.36 vs. 35.0+/-0.58, P=0.029), T45 (35.8+/-0.34 vs. 35.2+/-0.42, P=0.020), T60 (35.7+/-0.33 vs. 34.9+/-0.47, P=0.010), T75 (35.6+/-0.36 vs. 34.8+/-0.67, P=0.028), T90 (35.4+/-0.55 vs. 34.4+/-0.89, P=0.042), and T105 (34.9+/-0.53 vs. 33.9+/-0.85, P=0.024) were significantly higher than in the saline control group. Aminophylline is effective in maintaining the core temperature through a thermogenic effect, despite reduced peripheral thermoregulatory vasoconstriction.

Variaciones de la temperatura corporal de la interleuquina 6 y de la proteina C reactiva luego de la odontectomia de terceros molares / Changes in body temperature of the interleukin 6 and C-reactive protein after third molar odontectomy

Determinar las variaciones de la temperatura corporal, proteína C reactiva (PCR) y los niveles de Interleuquina 6 (IL-6) luego de la odontectomía de los terceros molares. Se seleccionaron 20 pacientes del Postgrado de Cirugía Bucal de la Facultad de Odontología de la Universidad Central de Venezuela, con indicación de extracción de los terceros molares retenidos y los cuales autorizaron por escrito su participación en el estudio. Los niveles de IL-6 fueron medidos por la prueba de ELISA, utilizando muestras de fluido crevicular gingival tomadas con puntas de papel estéril # 35, a las 0, 24, 48 horas y 7 días. Se realizó el registro de la temperatura corporal a las 0, 24, 48 horas y a los 7 días posteriores a la realización de la cirugía. Adicionalmente, se instruyó a los pacientes para la toma de la temperatura corporal cada 4 horas durante tres días consecutivos. Los niveles séricos de PCR se realizaron al tiempo 0 y a las 48 horas posteriores al acto quirúrgico. Se observó un aumento estadísticamente significativo en los niveles de IL-6, temperatura corporal y PCR luego de la odontectomía de los terceros molares. La elevación de la IL-6 se correlacionó en forma significativa con el incremento en la temperatura corporal y de la proteína C reactiva. La temperatura corporal, la IL-6 y la PCR aumentaron de manera directamente proporcional posterior al acto quirúrgico y en relación al trauma.

To determine variations in core body temperature, C-reactive protein (CRP) and interleukine-6 (IL-6) after surgical removal of third molars. Twenty patients who attended at the Oral Surgery Post grade in the Faculty of Dentistry, Universidad Central de Venezuela, for the extraction of the third molars. Informed consent was obtained from each patient. Samples of gingival crevicular fluid were collected with paper point # 35 at 0; 24 and 48 hours and at seventh day following to surgery, in order to measure IL-6 levels using ELISA test. The core body temperature was recorded at 0; 24; 48 hours and at 7th day after surgery. Additionally, the patients were instructed to register their temperature every 4 hours during three consecutive days. The CRP values were measured at time 0 and 48 hours later. Increase in IL-6, CRP and core body temperature values were observed after surgical extraction of third molars. The elevation of IL-6 was significantly correlated with the increase in CRP and body temperature. The core body temperature, IL-6 and CRP levels increased after surgical removal of third molars and were associated with the tissue damage.