The effects of facial fanning on thermal comfort sensation during hyperthermia

We studied how facial fanning during hyperthermia improves the thermal comfort sensation. Experiments were carried out on ten male subjects. They were immersed in hot water at 40 degrees C for 45 min. At 20 min and 35 min, fanning (1 m x s(-1)) was applied to their faces for 5 min. Core temperature (Tc) measured as esophageal temperature (Tes) and tympanic temperature (Tty) continued to rise during the immersion, but temporarily decreased during fanning with a delay of 2 or 3 min. Skin temperatures (Ts) on the forehead and cheek continued to increase slightly during immersion, but decreased immediately after the start of fanning. During immersion before face fanning, the time trend of thermal sensation towards the warm level was similar to that of skin temperature on the face, whereas the time trend of thermal comfort ratings towards the uncomfortable level was similar to that of Tc. The scores of both thermal sensation and thermal comfort were reduced significantly immediately after the start of fanning, and their time courses were different to those of Ts and Tty. These results support previous reports that thermal sensation depends on skin temperature, and that thermal comfort depends on both the skin and core temperatures. Moreover, they indicate that both thermal sensation and comfort ratings are affected by the dynamic responses of the cutaneous thermoreceptors when fanning is applied to the face during hyperthermia.     

Influence of magnetic resonance imaging on human body core and intravascular temperature

Deep and superficial body temperatures were measured by in vitro and in vivo experiments, using a fluoroptic procedure and a variety of magnetic and electromagnetic fields, in the course of magnetic resonance imaging (0.35 T; 1.5 T). In vitro experiments were performed to select and check the appropriate temperature method. Temperature measurements in the human body were carried out centrally (esophageal and rectal measurements). In vivo experiments in 30 volunteers showed no significant changes (p = 0.05) in central or peripheral temperatures resulting from the application of static or dynamic fields or radiofrequency.     

Effect of skin temperature on the cholinergic sensitivity of the human eccrine sweat gland

Although sweat gland activity is directly controlled by the central nervous system, which detects changes in core body temperature, sweat glands can also be influenced by local cutaneous thermal conditions. OBJECTIVE: The present study sought to determine the effect of local skin temperature on pilocarpine-induced sweating within a range of typical skin temperatures. METHODS: Thirteen subjects (30 +/- 6 years; 172 +/- 11 cm; 72.8 +/- 11.0 kg) had forearm sweat rates measured at rest following pilocarpine iontophoresis at each of three skin temperatures in randomized order: warm (T(warm) = 37.1 +/- 0.9 degrees C), control (T(con) = 32.3 +/- 1.4 degrees C), and cool (T(cool) = 26.6 +/- 1.3 degrees C). T(skin) was raised and lowered with an electric heating pad and gel ice pack, respectively. Forearm T(skin) was measured with a skin temperature probe. Pilocarpine iontophoresis was used on an approximately 7 cm(2) area of the anterior forearm to stimulate localized sweating. Following stimulation, sweat was collected from the area for 15 min with a Macroduct Sweat Collection System. RESULTS: There was a higher sweat rate at T(warm) (p = 0.001) and T(con) (p = 0.006) compared to that at T(cool). However, there was no difference between the sweat rate at T(warm) and that at T(con) (p = 0.127). CONCLUSION: These results indicated that skin temperatures below approximately 32 degrees C affect local sweat production primarily by altering glandular sensitivity to the neurotransmitter, whereas skin temperatures above approximately 32 degrees C predominantly affect neurotransmitter release. Furthermore, sweat glands display maximal or near maximal cholinergic sensitivity at resting skin temperature in a thermoneutral environment.     

Effect of facial cooling during heat acclimation process on adaptive changes in sweating activity

On assumptions that tympanic temperature (Tty) reflects brain temperature and that the latter can be lowered by cooling of the face, effect of facial cooling during acclimation process on adaptive changes in sweating activity was examined, in comparison with the results of our previous studies on heat acclimation with controlled hyperthermia. Face fanning, by which Tty was clamped at approximately 37.1 degrees C, was combined with either of the following 9-day acclimation procedures: 90-min heating in a "Sauna box," keeping mean skin temperature slightly above 40 C, or 90-min exercise on a bicycle, clamping rectal temperature (Tre) at approximately 38 degrees C. Each procedure was imposed on the same four male subjects on different occasions, two of whom had participated in our previous experiments. Sweat tests, carried out before and immediately after the completion of the procedure, consisted of measurements of local sweat rates, whole body sweat rate, Tre, Tty, and skin temperatures on 5 areas, and of calculations of mean body temperature (Tb) and the rate of sweat expulsions (Fsw, as an indicator of central sudomotor activity). No or only a slight increase in sweating activity was observed following the acclimation procedures with face fanning, whereas similar procedures without face fanning had resulted in substantial enhancement of sweating activity in most of the cases, which had been attributed mainly to adaptive changes in central sudomotor activity (as indicated by a shift of the regression line relating Fsw to Tb). Similar results were obtained in an additional series of experiments, where the effects of 9-day 90-min exercise in heat, clamping Tre at approximately 38.2 degrees C, with and without facial cooling, were compared with each other in a subject. From the above results it is inferred that Tty reflects brain temperature and that enhancement of sweating activity induced by repeated heat load is strongly impeded, if not accompanied, by an elevation of brain temperature.     

Effects of facial fanning on local exercise performance and thermoregulatory responses during hyperthermia

Summary To investigate the effects of hyperthermia and facial fanning during hyperthermia on hand-grip exercise performance and thermoregulatory response, we studied eight male subjects, aged 20–53 years. Subjects exercised at 20% of maximal hand-grip strength in the sitting position under three conditions: normothermia (NT), hyperthermia without fanning (HT-nf) or with fanning at 5.5 m · sec^–1 wind speed (HT-f). Hyperthermia (0.5° C higher oesophageal temperature than in NT) was induced by leg immersion in water at 42° C. Mean exercise performance was markedly reduced from 716 contractions (NT) to 310 (HT-nf) by hyperthermia (P<0.01) and significantly (P<0.05) improved to 431 (HT-f) by facial fanning. Hyperthermic exercise was accompanied by significant increases in forearm blood flow (71%) and the local sweat rate on the thigh (136%) at the end of exercise compared with that in NT. Heart rate (HR) and rating of perceived exertion (RPE) increased during exercise and were higher in HT-nf than in NT at any given time of exercise. Oesophageal, tympanic (T_ty) and mean skin temperatures were also significantly higher in HT-nf than in NT. Facial fanning caused a marked decrease in forehead skin temperature (1.5–2.0° C) and a slight decrease in T_ty, HR and PRE compared with that in HT-nf at any given time of exercise. These results suggested that hyperthermia increased thermoregulatory demands and reduced exercise performance. Facial fanning caused decreases in face skin and brain temperatures, and improved performance.     

Remote temperature monitoring in ocular tissue using confocal Raman spectroscopy

We demonstrated the feasibility of Raman spectroscopy for remote temperature monitoring within the aqueous humor of the rabbit eye in vivo. Using a confocal Raman spectroscopy system, Raman spectra from 2580 to 3800 cm(-1) were recorded in HPLC-grade water and in the aqueous humor of the rabbit eye under in vivo and ex vivo conditions within a temperature range of 14-34 degrees C. The ratio between the integrated Raman intensities of two temperature dependent OH-vibrational regions (OH2/OH1) in the spectra of water showed high linear dependence on temperature both in pure water [0.0049(+/-1.2%)T+0.4522(+/-0.5%), R2=0.99, n=50, p<0.05], as well as in the rabbit aqueous humor [0.0036(+/-2.8%)T+0.4966(+/-0.6%), R2=0.98, n=162, p<0.05] with a high degree of reproducibility and sensitivity ( approximately 0.2-0.7 degrees C). Raman spectroscopy can be used for high resolution and remote monitoring of temperature in the aqueous humor under in vivo conditions.     

A respiratory drive in addition to the increase in CO(2) production at raised body temperature in rats

Mammals that use the ventilatory system as the principal means of increasing heat loss, i.e. that pant, show two fundamental changes in the control of breathing at raised temperatures. First, alveolar ventilation increases by more than, rather than in proportion to, the increase in CO2 production. Second, hypocapnia no longer causes apnoea. Rats do not use the ventilatory system as the principal means of increasing heat loss, so we have investigated whether rats also show these two changes at raised temperatures. Breathing was detected from diaphragmatic electromyogram (EMG) activity. Anaesthesia and hyperoxia were used to minimise behavioural and hypoxic drives to ventilation and arterial PCO2 (Pa,CO2) was controlled using mechanical ventilation. At 36.6 +/- 0.1 >C, breathing was absent as long as Pa,CO2 was held below a threshold level of 32.9 +/- 0.7 mm Hg (n = 14) under steady-state conditions. When body temperature in rats was raised above 37 >C, both fundamental changes in the control of breathing became apparent. First, at 39 >C the mean Pa,CO2 level during spontaneous breathing (39.6 +/- 5.4 mm Hg, n = 4) fell by 3.9 +/- 1.4 mm Hg (P < 0.05, Student's paired t test). Second, at 39.9 +/- 0.1 >C breathing was present when mean Pa,CO2 levels were only 18.2 +/- 1.5 mm Hg (n = 14), the lowest mean Pa,CO2 level we could achieve with mechanical ventilation. We calculate, however, that at 39.9 >C, the drive to breathe from the increased CO2 production alone would not sustain breathing below a Pa,CO2 level of 27.8 +/- 1.4 mm Hg (n = 13). In rats at raised body temperatures therefore a respiratory drive exists that is in addition to that related to the increase in CO2 production.     

脑卒中患者的无创动脉硬化检测指标与颅内、外动脉狭窄相关性分析

目的：探讨脑卒中患者无创动脉硬化检测各项指标与颅内、外动脉狭窄发生率的相关性.方法：分别对340例脑卒中患者进行无创动脉硬化检测及经颅多普勒（TCD）检测,将动脉硬化检测各项指标与TCD发现一条以上颅内、颅外动脉狭窄者比较.结果：运用非条件Logistic回归分析显示,小动脉顺应性（C2）似然比检验P＜0.05,差异有统计学意义.结论：小动脉顺应性（C2）异常是导致颅内、外动脉狭窄的独立危险因子 。     

Determination of the PO2 temperature blood factor from oxygen dissociation curves

The variation with saturation of the temperature coefficient of PO2 in human blood (delta log PO2/delta T) was determined by continuous recording of the oxygen dissociation curve (ODC), at 37 degrees C and 25 degrees C, on the same blood samples. PCO2 and pH were held constant through an ODC run, and PCO2 was reduced at 25 degrees C to the value measured by anaerobic cooling of the same sample. delta log PO2/delta T was calculated from isosaturation points on the 37 and 25 degrees C curves. The temperature coefficient was also computed as an independent check on this method by determination of the effects of temperature (25, 30, 37 and 40 degrees C) on hemoglobin ligand interaction: fixed acid Bohr effect (delta log PO2/delta pH), carbamino-formation (delta log PO2/delta log PCO2) and hemoglobin oxygen affinity. The values of delta log PO2/delta T ratio obtained from the two different approaches were found to be in good agreement. The coefficient decreased when [H+] concentration was increased. A linear relationship between the Bohr factor and the temperature was found: delta log PO2/delta pH = 0.00267 T-0.520 (r = 0.85; n = 40) At 25 degrees C, the carbamino-formation was one order of magnitude lower than at 37 degrees C. Acid-base state and saturation value appeared to be major determinant factors for the temperature correction coefficient to be applied to blood PO2 values measured at standard (37 degrees C) temperature.     

Development of a continuous temperature mapping system using a deep body thermometer

To determine continuous body temperature distribution, an inexpensive temperature mapping system was developed using a deep body thermometer adopting the finite-element method. A stripe with 16 thermocouples was wrapped around the waist of rats to measure body surface temperatures (the boundary conditions). The abdominal deep temperature of the rats was measured from the dorsum using the thermal compensation probe of a deep body thermometer. The abdominal temperature of the rats was mapped by solving a heat conduction equation using surface and deep temperatures obtained in real time. The temperature measured with a thermocouple inserted into the abdominal centre of the rats correlated well with the calculated temperature (r = 0.93, p < 0.01). The system is low cost and simple to use compared with the magnetic resonance temperature mapping system. Our temperature mapping system could potentially result in improved management of patients in critical care medicine.     

The effect of cold air application on intra-articular and skin temperatures in the knee

The present study was performed to investigate the effect on the skin and the intra-articular structures of 5-minutes of cold air application. During and after 5 minutes of cold air application on 20 healthy subjects, the skin and intra-articular temperatures were measured by means of an infrared thermogram and a digital k-wire probe, respectively. The results showed that 1) Skin temperature dropped very rapidly by a total of 22.1 degrees C after 5 minutes of cold air application. 2) Intra-articular temperature dropped by 3.9 degrees C after 5 minutes of cold air application. 3) Two hours after the start of treatment with cold air, intra-articular temperatures had still not returned to their baseline values (p < 0.01). 4) The baseline skin temperature and the baseline intra-articular temperature were significantly correlated r=0.51 (p < 0.05). However, there was no significant correlation between the skin temperature change and the intra-articular temperature change after 5 minutes and after two hours of cold air application. Finally, 5) a significant correlation r=-0.72 (p < 0.01) between the body mass index and the baseline skin temperatures was found. There was no significant correlation between the body mass index and the temperature changes, at the skin or in the knee joint, either during or after cryotherapy (p > 0.05).     

后交通动脉开放与椎动脉颅内段发育间关系的MRA研究

目的　探讨后交通开放情况与椎动脉颅内段发育之间的关系。 方法　回顾性分析了115例3.0T磁共振血管成像（MRA）体检者。观察双侧椎动脉发育与双侧后交通动脉开放情况,测量椎动脉颅内段管径及后交通动脉的长度与管径,分析二者的相关性。 结果　 ①右侧椎动脉发育不良占39.13%（45/115）,缺如占0.87%（1/115）,左侧椎动脉发育不良占15.65%（18/115）,双侧椎动脉同时发育不良占2.61%(3/115)。②单侧或双侧后交通动脉开放72例,双侧同时开放35例,仅左侧开放23例,仅右侧开放14例。③椎动脉颅内段发育不良与后交通动脉开放相关（r=0.677,P=0.000）。 结论　椎动脉颅内段发育不良可引起后交通动脉代偿性开放。     

充气式温毯预保温联合液体加温对肺叶切除术患者体温及热舒适度的影响

目的本研究拟探讨充气式温毯预保温联合液体加温对胸科全麻肺叶切除术患者体温及热舒适度的影响。方法择期行胸腔镜(VATS)肺叶切除术患者46例,随机分为预保温(充气式温毯)+液体(温箱)保温组(T)和对照组(C),每组23例,记录预保温前后、麻醉过程中、术毕及进出麻醉术后恢复室(PACU)时患者鼓膜温及术后寒战、热舒适度、恢复室停留时间。结果在麻醉后1、2、3 h和术毕时4个时间点,与对照组相比,保温组患者术中的核心体温下降幅度小,更趋于稳定(P0.01);保温组患者术后低体温发生率,寒战发生率均较低(8.7%比56.5%,4.3%比34.8%,P0.05);保温组患者热舒适度评分高于对照组(8.52±0.94比7.65±0.83,P0.01)。结论术前预保温联合液体保温可维持全麻肺叶切除术患者术中体温平稳,降低低体温及寒战发生,提高热舒适度,为患者提供有效的体温保护。     

Fibroblast growth factor-19 levels in type 2 diabetic patients with metabolic syndrome

This study aimed to examine fibroblast growth factor-19 (FGF-19) in type 2 diabetic (T2DM) patients with metabolic syndrome (MetS) and to evaluate the relationship between FGF-19 and other cardiovascular risk factors, such as atherogenic index of plasma (AIP) and hsCRP. 26 T2DM patients with MetS and 12 healthy controls were enrolled in the study. Serum FGF-19 levels were measured by sandwich ELISA, and compared with other cardiovascular risk factors; lipid profile, AIP, glucose, HbA1c, and hsCRP. AIP was calculated as log (TG/HDL-c). The median (1-3.quartile) FGF-19 levels in T2DM patients with MetS and healthy controls were 122.90 (108.63-237.60) pg/ml and 293.45 (153.64-370.31) pg/ml, respectively (P=0.003). Patients were also grouped by body mass index (BMI) <30 kg/m(2) (n=13) and ≥30 kg/m(2) (n=13) with median (1-3.quartile) FGF-19 values 168.70 (113.54-275.77) pg/mL and 115.89 (97.94-200.40) pg/mL, respectively (P=0.007). Significant negative correlations were found between FGF-19 and BMI, triglyceride, log (TG/HDL-c), hsCRP, and HbA1c (r=-0.526, P=0.001; r=-0.327, P=0.05; r=-0.312, P=0.05; r=-0.435, P=0.006; r=-0.357, P=0.028, respectively). We showed that FGF-19 levels are low in T2DM patients with MetS. The negative relationship between FGF-19 and several known cardiovascular risk factors such as TG, log (TG/HDL-c), hsCRP and HbA1c in diabetic patients with MetS suggests that FGF-19 can be used as a contributing marker.     

Body core temperature during food restriction in rats

Deep body temperature and locomotor activity of rats fed a reduced food amount (n = 9) and of starved rats (n = 9), were measured by implanted transmitters. Both groups were then refed ad libitum. The reduction in body temperature was significant for both groups, but larger in the starved rats than in the food restricted rats. There was a displacement of the circadian temperature rhythm in the starved rats. There were no significant differences in locomotor activity between groups until the start of refeeding. Rats fed reduced food amounts rapidly increased their activity, while the starved group retained a low activity for several days. Thermal conductance was reduced by 30% in both groups. This reduction in thermal conductance may explain how starving and semistarving rats are able to maintain core temperatures close to normal, even if resting metabolic rates are drastically reduced. The measured reduction in body core temperature signifies a change in the thermoregulatory 'set-point' during starvation.     

Analysis of salivary testosterone by liquid chromatography-tandem mass spectrometry: correlation with serum bioavailable testosterone and aging

PURPOSE: To demonstrate that the salivary testosterone (T) concentration measured by liquid chromatography tandem mass spectrometry (LC-MS/MS) is a sensitive biomarker of serum bioavailable testosterone (bio T) concentration and it's decrease with age. METHOD: Saliva and blood samples were collected from healthy 53 Japanese men (16-66yr) three times a day (9: 00-10: 00, 13: 00-14: 00, 17: 00-18: 00). Salivary T and serum total T levels were compared with serum bio T levels fractionated with concanavaline A. All samples were measured by LC-MS/MS. The stability of salivary T concentrations stored at -70 degrees C for 2 months was also examined. RESULTS: Salivary T levels correlated with bio T(r=0.88, n=158) better than total T did (r=0.71, n=159). The decrease of T concentration with age was observed in saliva of each sampling time. In total T, the decrease with age was weaker and was insignificant in the late afternoon. Salivary T was stable for 2 months at -70 degrees C and a freeze/thaw cycle (difference: average 3.7%, SD=8.4%, n=84). CONCLUSIONS: Salivary T measured by LC-MS/MS is a reliable biomarker of T availability and its decrease with aging.     

冠心病患者甲状腺激素水平与血脂的关系

目的：探讨甲状腺功能正常的冠心病患者中血清甲状腺激素与血脂的相关性。方法：54例男性和74例女性冠心病患者在空腹状态下采集血标本,分别测定甲状腺激素、血脂和血糖水平。结果：Pearson相关分析显示：在男性组中总三碘甲状腺原氨酸（TT3）与低密度脂蛋白胆固醇（LDL-C）呈显著正相关（r=0.258,P〈0.05）,游离甲状腺素（FT4）与载脂蛋白B（apoB）呈显著负相关（r=-0.444,P〈0.05）;在女性组中TT3与载脂蛋白A1（apoA1）呈显著正相关（r=0.315,P〈0.05）,促甲状腺激素（TSH）与高密度脂蛋白胆固醇（HDL-C）呈显著正相关（r=0.234,P〈0.05）FT4与脂蛋白a[LP（a）]呈显著负相关（r=-0.291,P〈0.05）。结论：在甲状腺功能正常的冠心病患者中,甲状腺激素与血脂之间有一定的相关性。     

2型糖尿病患者免疫功能变化与血糖和胰岛素水平相关性的研究

探讨2型糖尿病患者免疫功能变化及其与血糖和胰岛素的相关性.检测34例2型糖尿病(T2DM)患者在空腹和口服75克葡萄糖后120min时的红细胞C3b受体花环(RBC-C3bRR)、红细胞免疫复合物花环(RBC-ICR)、T淋巴细胞亚群(CD3、CD4、CD8、CD4/CD8)、可溶性白介素-2受体(sIL-2R)、免疫球蛋白(IgG、IgA、IgM)、血糖和胰岛素.对照组30名.2型糖尿病患者与对照组相比,RBC-C3bRR、CD3、CD4、CD4/CD8和IgG、IgA均明显降低(P＜0.01,P＜0.05),而RBC-ICR、sIL-2R和CD8明显增高(P＜0.01,P＜0.05),服葡萄糖后120min时较空腹时更明显.RBC-C3bRR与血糖和胰岛素呈负相关(r1=-0.354,r2=-0.335,P＜0.05);RBC-ICR与血糖和胰岛素呈正相关(r3=0.368,r4=0.342,P＜0.05);CD3、CD4、CD4/CD8、IgA与血糖呈负相关(r5=-0.302,r6=-0.378,r7=-0.413,P＜0.01;r8=-0.332, P＜0.01);CD8和sIL-2R与血糖呈正相关(r9=0.214,P＜0.05;r10=0.437,P＜0.01).T2DM患者存在多项免疫指标变化,其免疫功能低下与血糖和胰岛素升高有相关性.     

慢性HBV感染者外周血CD4+CD25high调节性T细胞初步分析

目的 分析不同临床乙型肝炎病毒(HBV)慢性感染者外周血中CD4+CD25high调节性T细胞(Treg)的水平及其与各种临床指标的关系.方法 采集35例不同临床表现成年慢性HBV感染者(HBsAb+组5例、非活动肝炎组8例、活动肝炎组12例、免疫耐受期组10例)及12例健康成人外周血标本,流式细胞仪分析外周血中CD4+CD25high Treg含量,ELISA法检测HBsAg、HBsAb、HBeAg、HBeAb、HBcAb,RT-PCR法检测HBV DNA载量,同时进行肝脏生化功能检测,并进行统计学分析.结果 HBV慢性感染者[(12.35±6.48)个/μl;(1.82 4-0.87)%)]及健康成人外周血标本[(8.91±3.11)个/μl,(1.35±0.39)%]中CD4+CD25highTreg绝对计数和其占CD4+T细胞百分含量差异均无统计学意义(P＞0.05);分组分析发现,免疫耐受期组CD4+CD25highTreg占CD4T细胞百分含量高于HBsAb+组、活动肝炎组及健康对照组(P＜0.05);免疫耐受期组CD4+CD25highTreg绝对计数高于健康对照组(P＜0.05);余各组间差异无统计学意义(P＞0.05).分析CD4+CD25highTreg含量与临床指标间相关性发现,CD4+CD25highTreg占CD4+T细胞百分含量与丙氨酸氨基转移酶(ALT)水平呈负相关(r=-0.418,P=0.038),与CD4/CD8比值呈正相关(r=0.344,P=0.021),与HBV DNA水平无相关性(r=0.118,P＞0.05);CD4+CD25highTreg绝对计数与CD4/CD8比值呈正相关(r=0.360,P=0.015),与ALT水平及HBV DNA水平无相关性(r=-0.211,r=-0.060,P＞0.05).结论 CD4+CD25highTreg在HBV慢性感染的免疫发病机制中可能发挥一定作用.     

睾酮对大鼠心肌梗塞后心肌肥大的影响

本文应用立体形态定量技术,观察睾酮(T)对心肌梗塞后心肌肥大的影响。实验分为:假手术组(S组)、心肌梗塞组(MI组)。心肌梗塞后睾酮治疗组(MIT组)。结果证明,与S组相比,MI及MIT组大鼠心肌细胞核密度明显减少,尤其以MIT组变化显著,MIT组平均核长度明显增加;MI组的 dp/dt max明显降低,T值延长,MIT组的上两指标无显著差异。MI后血浆T总浓度与平均每核心肌细胞体积呈显著正相关关系。提示:睾酮确实促进了MI后心肌肥大,从而促进了心功能的恢复。