Cutaneous Temperature Research Articles

Effect of virtual reality and whole-body heating on motion sickness severity: A combined and individual stressors approach

BackgroundVirtual reality (VR) use is limited by the potential side effects of prolonged exposure to vection, leading to motion sickness. Air temperature (Ta) may exacerbate the severity of such side effects through a synergistic interaction. This study assessed the individual and combined impact of a hot Ta and VR on motion sickness severity. MethodThirteen healthy volunteers were exposed to a 20 min visual stimulus, across four experimental conditions: N_CS: 22 °C Ta with computer screen; N_VR: 22 °C Ta with VR; H_CS: 35 °C Ta with computer screen; H_VR: 35 °C Ta with VR. Motion sickness was assessed via fast motion sickness scale (FMS) and simulator sickness questionnaire (SSQ). Physiological indices of motion sickness including, sweat rate, rectal temperature, cutaneous vascular conductance (CVC), skin temperature, blood pressure and heart rate were also examined. ResultsFMS and SSQ ratings indicate a significant main effect for VR, increasing sickness severity (p < 0.001). A significant main effect of Ta was observed for SSQ, but not FMS ratings (FMS, p = 0.07; SSQ, p < 0.04). Despite trends towards synergism, no interaction (Ta × VR) was observed for FMS (p = 0.2) or SSQ scores (p = 0.07), indicating an additive response. Synergistic trends were also observed for sweat rate and CVC. ConclusionSynergism between VR and heat on motion sickness remains unclear, possibly as a result of considerable inter-individual variation in the reported subjective responses. Understanding of the questions raised by this study inform safe working guidelines for the use of VR in commercial and occupational settings.

Infrared thermography to assess dermatomal levels of labor epidural analgesia with 1 mg/mL ropivacaine plus 0.5 µg/mL sufentanil: a prospective cohort study

BackgroundAssessment of the effectiveness of obstetric epidural analgesia may be difficult and techniques for objective assessment of epidural spread of local anesthetic would be useful. In this prospective cohort study we assessed whether obstetric epidural analgesia from a low concentration of ropivacaine led to significant change in cutaneous temperature, related to sympathetic block detected by infrared thermography, at dermatomes C4, T4, T10, L2 and L5. MethodsWomen in spontaneous labor who requested epidural analgesia were consecutively recruited. Epidural analgesia was induced with a bolus of 10–15 mL of ropivacaine 1 mg/mL and sufentanil 0.5 µg/mL, followed by continuous epidural infusion. Skin temperature was measured using thermography before and 20 min after the epidural bolus. The verbal pain score using a numeric rating scale was recorded before and 60 min after the epidural bolus. The upper sensory block to cold sensation was tested 30 and 60 min after the bolus by a physician blinded to the skin temperature. Failed epidural analgesia was defined as verbal pain score >3 at 60 min. ResultsFifty-three parturients were included and analyzed. We found a significant increase in skin temperatures measured at T4, T10, L2 and L5 dermatomes, but not at C4, and a significant difference in the change in skin temperature at T10 between failed (n=3) and successful (n=50) epidural analgesia. ConclusionsThese results suggest that infrared thermography might be useful for the early diagnosis of successful obstetric epidural analgesia.

Contribution of Chinese and French ear acupuncture for the management of chronic back pain: A randomised controlled trial.

To compare the efficacy of Chinese and French ear acupuncture in people with chronic back pain. Chronic back pain is a common public health problem worldwide. An intervention for this condition is ear acupuncture. Several approaches are used for ear acupuncture, particularly the Chinese and French guidelines. An open, randomised and controlled clinical trial, followed the recommendations of the CONSORT Checklist. One hundred and eleven people were selected and randomised into three groups: Chinese ear acupuncture, French ear acupuncture and Control. Evaluations were performed before the first intervention session (initial), 1week after the fifth session (final) and after a fifteen-day follow-up period (follow-up), using the Brief Pain Inventory, Rolland Morris Disability Questionnaire, and a thermal imaging camera. For data analysis, the Generalized Estimating Equation Model was applied, with significance level set at 5%. Pain severity was significantly decreased by Chinese ear acupuncture throughout intervention period. Both types of ear acupuncture affected pain interference with daily activities. However, in the comparison between initial and final evaluations, only Chinese ear acupuncture produced statistically significant results. A reduction in physical disability was observed in both ear acupuncture-treated groups during the intervention period and, although Chinese ear acupuncture failed to induce significant changes in tissular temperature at individual time points, a significant increase in cutaneous temperature was detected after the follow-up period in the dorsal region of individuals treated with Chinese ear acupuncture. Importantly, at this time point, the mean difference between Chinese and French ear acupuncture revealed a more benefic effect of Chinese procedure on this parameter. The individualised treatment based on the Chinese precepts showed, in an overall evaluation, better results for management of chronic back pain in the present study. Ear acupuncture can be implemented in the nurse's clinical practice to assist the treatment of people with chronic back pain.

Genotype by environment interactions for performance and thermoregulation responses in growing pigs1,2.

Heat stress affects pig health, welfare, and production, and thus the economic viability of the pig sector in many countries. Breeding for heat tolerance is a complex issue, increasingly important due to climate change and the development of pig production in tropical areas. Characterizing genetic determinism of heat tolerance would help building selection schemes dedicated to high performance in tropical areas. The main objective of our study was to estimate the genetic parameters for production and thermoregulation traits in two highly related growing pig populations reared in temperate (TEMP) or tropical humid (TROP) environment. Pigs came from a backcross population between Large White (LW, heat sensitive) and Creole (CR, heat tolerant) pigs. Phenotypic data were obtained on a total of 1,297 pigs using the same procedures in both environments, for body weight (BW, at weeks 11 and 23), daily feed intake (ADFI), backfat thickness (BFT, at weeks 19 and 23), cutaneous temperature (CT, at weeks 19 and 23), and rectal temperature (RT, at weeks 19, 21, and 23). Feed conversion ratio (FCR) and residual feed intake (RFI) were computed for the whole test period (11 to 23 wk). Criteria comparing the fits to the data revealed genotype × environment (G × E) interactions for most traits but not for FCR. The variance components were obtained using two different methods, a restricted maximum likelihood method and a Bayesian Markov chain Monte Carlo method, considering that traits are either similar or different in each environment. Regardless of the method, heritability estimates for production traits were moderate to high, except for FCR (lower than 0.18). Heritability estimates for RT were low to moderate, ranging from 0.04 to 0.34. The genetic correlations of each trait between environments generally differed from 1, except for FCR and ADG. For most thermoregulation traits, they also did not differ significantly from zero, suggesting that the main genetic bases of heat tolerance may vary in different environment. Within environments, the unfavorable genetic correlations between production traits and RT suggest an antagonism between the ability to maintain inner temperature and the ability to increase ADFI and ADG. However, greater RT were also associated to leaner pigs and better feed efficiency. Nevertheless, due to large inaccuracies of these estimations, larger cohorts would be needed to decide about the best breeding schemes to choose for tropical pig production.

"Beet" the cold: beetroot juice supplementation improves peripheral blood flow, endothelial function, and anti-inflammatory status in individuals with Raynaud's phenomenon.

Raynaud's phenomenon (RP) is characterized by recurrent transient peripheral vasospasm and lower nitric oxide (NO) bioavailability in the cold. We investigated the effect of nitrate-rich beetroot juice (BJ) supplementation on 1) NO-mediated vasodilation, 2) cutaneous vascular conductance (CVC) and skin temperature (Tsk) following local cooling, and 3) systemic anti-inflammatory status. Following baseline testing, 23 individuals with RP attended four times, in a double-blind, randomized crossover design, following acute and chronic (14 days) BJ and nitrate-depleted beetroot juice (NDBJ) supplementation. Peripheral Tsk and CVC were measured during and after mild hand and foot cooling, and during transdermal delivery of acetylcholine and sodium nitroprusside. Markers of anti-inflammatory status were also measured. Plasma nitrite concentration ([nitrite]) was increased in the BJ conditions (P < 0.001). Compared with the baseline visit, thumb CVC was greater following chronic-BJ (Δ2.0 flux/mmHg, P = 0.02) and chronic-NDBJ (Δ1.45 flux/mmHg, P = 0.01) supplementation; however, no changes in Tsk were observed (P > 0.05). Plasma [interleukin-10] was greater, pan endothelin and systolic and diastolic blood pressure (BP) were reduced, and forearm endothelial function was improved, by both BJ and NDBJ supplementation (P < 0.05). Acute and chronic BJ and NDBJ supplementation improved anti-inflammatory status, endothelial function and blood pressure (BP). CVC following cooling increased post chronic-BJ and chronic-NDBJ supplementation, but no effect on Tsk was observed. The key findings are that beetroot supplementation improves thumb blood flow, improves endothelial function and anti-inflammatory status, and reduces BP in people with Raynaud's.NEW & NOTEWORTHY This is the first study to examine the effect of dietary nitrate supplementation in individuals with Raynaud's phenomenon. The principal novel findings from this study were that both beetroot juice and nitrate-depleted beetroot juice 1) increased blood flow in the thumb following a cold challenge; 2) enhanced endothelium-dependent and -independent vasodilation in the forearm; 3) reduced systolic and diastolic blood pressure, and pan-endothelin concentration; and 4) improved inflammatory status in comparison to baseline.

Post-mastectomy pain syndrome after mamma reduction plasty, an unusual case report

CRPS (complex regional pain syndrome) is well documented as a reflex sympathetic dystrophy. It mostly has been reported to occur in the extremities and has only been mentioned anecdotally in the breast after breast surgery or trauma of the chest wall. Recent literature describes a post-mastectomy pain syndrome (PMPS), which mimics CRPS symptoms and, despite the nomenclature, is not only limited to mastectomy procedures but also any other surgical procedure involving breast parenchyma. We report PMPS in a 39-year-old patient after revision operation of breast reduction surgery. Postoperatively, the patient showed symptoms of severe persistent pain, swelling, cutaneous temperature changes, and hyperhidrosis in the affected breast. Subcutaneous infiltration with triamcinolone acetonide and prilocaine only relieved the symptoms temporarily. Botox injections did not relieve her symptoms of sweating either. Two intercostal nerve branches were identified with ultrasonography and dissected in general anesthesia. This procedure relieved her symptoms. Surgeons should consider CRPS and PMPS as differential diagnosis of chronic disproportionate pain after breast surgery. Early identification and treatment will help alleviate persistent CRPS symptoms and avoid chronic soft tissue changes. Level of evidence: Level IV, diagnostic/therapeutic study.

Sasa Quelpaertensis Nakai Induced Antidepressant-Like Effect in Ovariectomized Rats.

Background Sasa quelpaertensis Nakai extract (SQE) or dwarf bamboo has been extensively investigated for its antioxidant and anti-inflammatory effects; however, no previous study assessed its effect as an antidepressant agent. Therefore, this study was designed to examine the effect of oral SQE administration in ameliorating menopausal depressive symptoms and to evaluate its mechanisms in ovariectomized rats with repeated stress. Methods All experimental groups except normal group underwent ovariectomy and then immobilization for 14 consecutive days. During these 2 weeks, two rat groups received SQE (100 and 300 mg/kg orally) and their cutaneous body temperature was measured. The tail suspension test (TST) and forced swim test (FST) were performed in order to evaluate depression-like behavior. Additionally, enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry were carried out to evaluate the central monoaminergic neurotransmitter levels and activity. Results Oral SQE (100 mg/kg) administration had reduced immobility time in TST and FST. Additionally, the SQE 100 and 300 mg/kg administration had decreased the cutaneous body temperature in the rats compared to those without treatment. In ELISA analysis, the SQE 100 group expressed elevated levels of serotonin and dopamine in the hypothalamus, prefrontal cortex, and hippocampus. Antityrosine hydroxylase (anti-TH) antibodies showed a tremendous increase in the density of TH positive cells in the locus coeruleus (LC) region of the SQE 100 group. Likewise, the SQE 100 elevated the number of tryptophan hydroxylase (TPH) and protein kinase C (PKC) immunoreactive cell counts and density in the hypothalamic region. Conclusion These results suggested that the oral SQE administration induced the antidepressant-like effect in the ovariectomized rats with repeated stress via upregulating the levels of serotonin and dopamine through enhancing the expression of TH, TPH, and PKC in many brain areas.

Cross-sectional study of quadriceps properties and postural stability in patients with chronic stroke and limited vs. non-limited community ambulation

ABSTRACTBackground: Changes in the paretic-side metabolism post-stroke and quadriceps muscle mechanical properties favour muscle wasting, affecting postural instability and walking impairment. Further clarification is needed in subjects post-stroke who show limited or non-limited community ambulation.Objectives: To analyze between-limb differences in quadriceps muscle thickness, strength and thigh cutaneous temperature, as well as investigate postural stability in subjects with chronic stroke and limited vs. non-limited community ambulation and compared against healthy controls.Methods: In this controlled cross-sectional study, 26 participants with chronic hemiparesis post-stroke (divided in a slow gait group (SG<0.8 m/s) (n = 13) and a fast gait group with full community ambulation speed (FG≥0.8 m/s)) and 18 healthy people were recruited. Thigh surface temperature, rectus femoris (RF) and vastus intermedius (VI) muscles thickness, quadriceps’ isometric maximal voluntary contraction and postural stability were measured.Results: The SG presented significantly lower RF (P = .019) and VI (P = .006) muscle thickness, less peak force (P < .001) and lower temperature (P = .002) in the paretic vs the non-paretic limb. The FG showed significantly lower VI thickness (P = .036) and peak force (P < .001) in the paretic vs the non-paretic limb. Regarding balance, all indices were worse in the SG versus the FG and CG.Conclusions: Subjects of the FG, despite showing full community ambulation speed, had less quadriceps strength and VI muscle thickness but not RF muscle wasting in the paretic limb. The paretic VI muscle wasting may be an important factor to reach normal walking. The SG showed between-limb differences in all the studied variables and the worst postural stability.

MON-LB016 Sex and Sex Steroid Effects on Brown Adipose Tissue Temperature in Healthy Humans

Retrospective studies indicate that women have more brown adipose tissue (BAT) than men. Furthermore, animal studies show that sex steroids modulate BAT activity, wherein estrogen increases BAT function. We aimed to characterize BAT thermogenesis using infrared thermography (IRT) in healthy men (n=14; age 23.07 ± 0.7 years, BMI 23.22 ± 0.7 kg/m2) and in women during 2 stages of the menstrual cycle (luteal, n=9; age 25.22 ± 1.7 years, BMI 21.56 ± 0.4 kg/m2 and follicular, n=11; age 24.64 ± 1.2 years, BMI 22.12 ± 0.9 kg/m2). We measured cutaneous temperature in the supraclavicular (BAT positive) and the manubrium (BAT negative) regions, at baseline and in response to dietary and cold stimuli. Temperature recordings were at 1 min intervals, at an ambient temperature of 18.5-20°C. To activate cold-induced thermogenesis, one hand was immersed into water at 15°C for 5 min. Post-prandial thermogenesis was stimulated by the consumption of a liquid meal (Ensure, 10 kcal/ kg body weight). In fasted participants, baseline BAT temperature was higher (P<0.05) in women during the luteal phase than in either women during the follicular phase or men. Innate variation in baseline temperature was correlated (P<0.001) with serum progesterone concentrations, without being associated with estrogen or testosterone concentrations. The temperature response to cold exposure was biphasic, with an initial increase during cold exposure and a secondary increase approximately 20 min later; the latter phase has been referred to as adaptive thermogenesis. Women had greater (P<0.05) adaptive thermogenic responses to cold and dietary stimuli and this effect was greater (P<0.05) during the luteal phase of the menstrual cycle. During cold-exposure, the increase in BAT temperature was lower (P<0.05) in females during the follicular phase than during the luteal phase. Post-cold and post-prandial adaptive thermogenesis was greater in women than men, irrespective of the stage of menstrual cycle. Regression analyses showed that the degree of adaptive thermogenesis was positively correlated with serum estrogen concentrations (cold; P<0.05, meal; P=0.07), but negatively associated with serum testosterone concentrations (cold; P=0.07, meal; P<0.05). In summary, women typically display greater thermogenic responses than men, with an influence of the stage of menstrual cycle in women. Furthermore, we highlight that innate variation in BAT temperature and thermogenic responses to cold and diet are associated with fluctuations in the circulating levels of estrogen, progesterone and testosterone. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. s presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

CLO19-048: Effects of Acupuncture on Cutaneous Microcirculation by Infrared Thermography in Cancer Patients

Objectives: The objective of this case series was to describe the experience of the use of infrared thermography to evaluate the effects of acupuncture on cutaneous microcirculation of cancer patients. Methods: The method is a cross-sectional survey, descriptive of a series of cases of a sample for convenience. The data collection procedure had a total duration of 30 minutes, being captured images at different times during the procedure: before the needling (T0); first minute (T0a); second minute (T0b); third minute (T0c); forth minute (T0d); fifth minute (T1); tenth minute (T2); and after 15 minutes (T3) of needling. Body temperature was evaluated by infrared camera, brand FLIR, series A. The FLIR Tools software version 5.9 was used to perform the calculation of the temperatures with subsequent descriptive analysis of the data. The choice of the PC6, BP10, R6, and B62 bilateral acupoints was because of the anatomic location and energetic actions on the blood circulation. The PC6 acupoint (Neiguan) is located in the meridian of the pericardium, lies on the anterior face of the forearm approximately 2 cm (0.79 inches) below the wrist and between the flexor tendons. This acupoint is responsible for sending signals to the central nervous system, which results in the reduction of sympathetic activity. Results: According to the ANOVA test, considering P value less than or equal to .05, there were statistically significant differences in the time intervals evaluated, with P value of .004. There was a 1.7% increase in the mean temperature of the interval between T3 and T0 in the sample, that is, between the time before and after 15 minutes of needling. Conclusion: This series of cases showed the viability of the method of evaluating the effects of acupuncture on cutaneous microcirculation by infrared thermography in the rehabilitation of cancer patients. The results showed statistically significant differences in the time intervals evaluated, demonstrating the importance of the evaluation at 15 minutes after needling to accurately verify the variation of cutaneous temperature by thermography in the acupoints. It was noticed that the increase of the cutaneous temperature occurred, mainly, in the first 5 minutes after the needling, with a reduction after this time interval.

Role of the endocannabinoid system in the dorsal hippocampus in the cardiovascular changes and delayed anxiety-like effect induced by acute restraint stress in rats.

The dorsal hippocampus has a central role in modulating cardiovascular responses and behavioral adaptation to stress. The dorsal hippocampus also plays a key role in stress-associated mental disorders. The endocannabinoid system is widely expressed in the dorsal hippocampus and modulates defensive behaviors under stressful conditions. The endocannabinoid anandamide activates cannabinoid type 1 receptors and is metabolized by the fatty acid amide hydrolase enzyme. We sought to verify whether cannabinoid type 1 receptors modulate stress-induced cardiovascular changes, and if pharmacological fatty acid amide hydrolase inhibition in the dorsal hippocampus would prevent the cardiovascular responses and the delayed anxiogenic-like behavior evoked by restraint stress in rats via cannabinoid type 1 receptors. Independent groups received intra-dorsal-hippocampal injections of N-(piperidin-1yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-hpyrazole-3-carboxamide (AM251; cannabinoid type 1 receptor antagonist/inverse agonist, 10-300 pmol) and/or cyclohexyl carbamic acid 3'-carbamoyl-biphenyl-3-yl ester (URB597; fatty acid amide hydrolase inhibitor, 10 pmol) before the restraint stress session. Cardiovascular response during restraint stress or later behavioral parameters were evaluated. Acute restraint stress altered the cardiovascular response, characterized by increased heart rate and mean arterial pressure, as well as decreased tail cutaneous temperature. It also induced a delayed anxiogenic-like effect, evidenced by reduced open arm exploration in the elevated plus maze 24 h after stress. AM251 exacerbated the stress-induced cardiovascular responses after injection into the dorsal hippocampus. In contrast, local injection of URB597 prevented the cardiovascular response and the delayed (24 h) behavioral consequences of restraint stress, effects attenuated by pretreatment with AM251. Our data corroborate previous results indicating that the hippocampal endocannabinoid system modulates the outcome of stress exposure and suggest that this could involve modulation of the cardiovascular response during stress exposure.

Brown adipose tissue thermogenesis in polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is associated with increased obesity with a greater propensity to weight gain and a lack of sustainable lifestyle interventions. Altered brown adipose tissue (BAT) thermogenesis is a potential contributor to obesity in PCOS. BAT activity and modulation have not been studied in PCOS. This observational study explored BAT thermogenesis and its associations in women with and without PCOS. Cutaneous temperature was recorded from supraclavicular (indicator of BAT activity) and upper arm regions using dataloggers (SubCue, Calgary, Canada) in a cross-sectional substudy, nested within a randomized control trial, of community-recruited premenopausal women with (n=47, Rotterdam diagnostic criteria) and without (n=11) PCOS. Complete temperature data were available in 44 PCOS (mean age: 30.0±6.2, mean BMI: 29.3±5.5) and 11 non-PCOS (mean age: 33.0±7.0, mean BMI: 25±3) women. Women with PCOS had lower supraclavicular skin temperature compared to controls overall (33.9±0.7 vs 34.5±1, P<0.05) and during sleep (34.5±0.6 vs 35.2±0.9, P<0.001). In the PCOS group, supraclavicular skin temperature overall and over sleep and waking hours correlated inversely with testosterone (r=-0.41 P<0.05, r=-0.485 P<0.01 and r=-0.450 P<0.01 respectively). Testosterone levels explained approximately 15%, 30% and 20% of the variability in supraclavicular skin temperature overall and over sleep and waking hours in women with PCOS, respectively. Women with PCOS have lower BAT activity compared to controls. BAT thermogenesis is negatively associated with androgen levels in PCOS.

The Effect of a 300 mBar Increase in Barometric Pressure on Digital Microcirculation in Healthy Subjects Exposed to High Altitude: Is the Use of a Portable Hyperbaric Chamber to Treat Frostbite and/or Hypothermia in the Field Indicated? (Flow_Pulse Study).

Hypothermia and frostbite occur when there is a significant decrease in central and peripheral body temperature in individuals exposed to cold windy conditions, often at high altitude or in a mountain environment. Portable hyperbaric chambers increase the barometric pressure and thereby the partial pressure of oxygen inside the chamber, and their use is a well-known treatment for altitude illness. This study aims to show that a portable hyperbaric chamber could also be used to treat hypothermia and frostbite in the field, when rescue or descent is impossible or delayed. During a European research program (SOS-MAM, Flow Pulse study) measurements were taken from 27 healthy nonacclimatized voluntary subjects (21 men, 6 women, mean age 41 ± 17) at an altitude of 3800 m (Chamonix Mountain Lab, Aiguille du Midi, France) right before and immediately after spending 1 hour in a portable hyperbaric chamber at 300 mbar. We measured digital cutaneous temperature (Tcut), digital cutaneous blood flow (Fcut), digital tissue oxygenation (TcPO2), blood oxygen saturation (SpO2), heart rate, and core temperature. Air temperature inside the chamber (Tchamb) was measured throughout the whole session. We observed significant increases in Tchamb: 9.3°C compared with the outside temperature, Tcut: +7.5°C (±6.2°C 71%), Fcut: +58PU (±89) (+379%), TcPO2: +18 mmHg (±11.9) (304%), and SpO2: 13%. This study shows that a portable hyperbaric chamber can be used to treat frostbite and/or hypothermia in the field at altitude when descent or rescue is impossible or even simply delayed.

The Antidepressant-Like Effect of Lactate in an Animal Model of Menopausal Depression.

Background: This study aimed to investigate the antidepressant-like effect of lactate and elucidate its mechanisms in ovariectomized rats with repeated stress. Methods: Two experiments were conducted on female rats in which all groups, except normal, were ovariectomized and underwent immobilization for 14 days. Lactate was administered orally (100, 250, and 500 mg/kg) for 14 consecutive days, and the rats’ cutaneous body temperature was measured during the same period. Depression-like behavior in rats was assessed by the tail suspension test (TST) and forced swimming test (FST). Furthermore, enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry were conducted to evaluate the changes that occurred in the neurotransmitter levels and activity. Results: The lactate 100 and 250 groups had reduced time spent immobile in TST and FST and decreased peripheral body temperature. In ELISA tests, the lactate 250 group expressed elevated levels of serotonin and dopamine in many brain areas. Tyrosine hydroxylase (TH), tryptophan hydroxylase (TPH), and protein kinase C (PKC) immunoreactive cells showed increased density and cell counts in lactate administered groups. Conclusion: Results indicated that lactate has an antidepressant effect that is achieved by activation of PKC and upregulation of TH and TPH expression, which eventually leads to enhanced serotonin and dopamine levels in the menopausal rat’s brain.

Nitrergic neurotransmission in the paraventricular nucleus of the hypothalamus modulates autonomic, neuroendocrine and behavioral responses to acute restraint stress in rats

We investigated the involvement of nitrergic neurotransmission within the paraventricular nucleus of the hypothalamus (PVN) in modulation of local neuronal activation, autonomic and neuroendocrine responses and behavioral consequences of acute restraint stress in rats. Bilateral microinjections of the selective neuronal nitric oxide (NO) synthase (nNOS) inhibitor Nw-Propyl-L-arginine (NPLA) or the NO scavenger carboxy-PTIO into the PVN reduced arterial pressure and heart rate increases, as well as the fall in cutaneous tail temperature induced by restraint stress. PVN injection of either NPLA or carboxy-PTIO also inhibited restraint-induced increases in anxiety-related behaviors in the elevated plus-maze 24 h later. Local microinjection of NPLA or carboxy-PTIO into the PVN reduced the number of c-fos-immunoreactive neurons in the dorsal parvocellular, ventromedial, medial parvocellular and lateral magnocelllular portions of the PVN in animals subjected to restraint stress. However, neither NPLA nor carboxy-PTIO into the PVN affected restraint-induced increases in plasma corticosterone concentration. The present results indicate that PVN nitrergic neurotransmission acting via nNOS activation has a facilitatory influence on autonomic responses to acute restraint and the delayed emotional consequences of restraint stress. Our results also provide evidence of a prominent role of local nitrergic neurotransmission in PVN neuronal activation during stress.

Intra-operative cutaneous temperature monitoring with zero-heat-flux technique (3M SpotOn) in comparison with oesophageal and arterial temperature

Continuous monitoring of core temperature is essential during major surgery as a way of improving patient safety. Oesophageal probes or specific arterial catheters are invasive methods used in this setting. A new noninvasive device based on zero-heat-flux (ZHF) technique (SpotOn) seems promising but has been poorly investigated during rapid core temperature changes (RCTC). To assess the accuracy of a SpotOn sensor vs. an oesophageal probe or specific arterial catheter during a slow change in core temperature of less than 1 °C within 30 min and RCTC ≥ 1 °C within 30 min. Prospective observational study. Operating rooms at the University Hospital of Poitiers, France. Fifty patients scheduled for major abdominal surgery under general anaesthesia were enrolled from June 2015 to March 2016. Data from 49 patients were finally analysed. Among these, 15 patients were treated with hyperthermic intraperitoneal chemotherapy. Each patient had a ZHF sensor placed on the skin surface of the forehead (TempZHF) and an oesophageal probe (TempEso) used as a reference method. Twenty-two patients also had a thermodilution arterial catheter (TempArt) placed in the axillary artery. Core temperature was continuously recorded from the three devices after induction of anaesthesia. Comparison of temperature measurements between methods was made using the Bland and Altman method during two separate periods according to the speed of core temperature changes. Compared with TempEso, bias and limits of agreement for TempZHF were 0.1 ± 0.5 °C during slow core temperature changes periods and 0.6 ± 1.8 °C during RCTC periods (P = 0.0002). Compared with TempArt, these values were -0.1 ± 0.4 and 0.5 ± 1.7 °C, respectively (P = 0.0039). The ZHF sensor was well tolerated. A SpotOn sensor using the ZHF method seems reliable for core temperature monitoring during abdominal surgery when variations in core temperature are slow rather than rapid. ClinicalTrials.gov identifier: NCT02869828.

Limb Skin Temperature as a Tool to Predict Orthostatic Instability.

Orthostatic instability is one of the main consequences of weightlessness or gravity challenge and plays as well a crucial role in public health, being one of the most frequent disease of aging. Therefore, the assessment of effective countermeasures, or even the possibility to predict, and thus prevent orthostatic instability is of great importance. Heat stress affects orthostatic stability and may lead to impaired consciousness and decrease in cerebral perfusion, specifically during the exposure to G-forces. Conversely, peripheral cooling can prevent orthostatic intolerance – even in normothermic healthy subjects. Indicators of peripheral vasodilation, as elevated skin surface temperatures, may mirror blood decentralization and an increased risk of orthostatic instability. Therefore, the aim of this study was to quantify orthostatic instability risk, by assessing in 20 fighter jet pilot candidates’ cutaneous limb temperatures, with respect to the occurrence of G-force-induced almost loss of consciousness (ALOC), before and during exposure to a push-pull maneuver, i.e., head-down tilt, combined with lower body negative pressure. Peripheral skin temperatures from the upper and lower (both proximal and distal) extremities and core body temperature via heat-flux approach (i.e., the Double Sensor), were continuously measured before and during the maneuver. The 55% of subjects that suffered an ALOC during the procedure had higher upper arm and thigh temperatures at baseline compared to the 45% that remained stable. No difference in baseline core body temperature and distal limbs (both upper and lower) skin temperatures were found between the two groups. Therefore, peripheral skin temperature data could be considered a predicting factor for ALOC, prior to rapid onset acceleration. Moreover, these findings could also find applications in patient care settings such as in intensive care units.

Psychological and physiological responses to airflow stimuli: Differences in responses based on sex and targeted body site

The purpose of this study was to clarify the effects of psychological and physiological measures of body sites and sex on the perception of different frequencies and speeds of airflow. In this study, we administered various airflow stimuli, which were produced by an airflow-generating device developed in a previous study, to 20 participants (10 men and 10 women) on the back of the hand, palm, cheek, and back of the neck in a room with the temperature set to 20 °C and humidity to 65%. We found the following: 1) Higher airflow speeds were associated with a greater decline in cutaneous temperature, higher coldness scores, and more negative preference scores. While a higher amplitude and frequency of sine wave signal (FSS) was associated with higher coldness scores, a higher level of temperature decline (delta-T) accompanying a higher FSS did not influence the preference score. 2) Women tended to give higher coldness scores and more positive preference scores, and men tended to give lower coldness scores and more negative preference scores. 3) Coldness scores were highest for the back of the hand, followed in order by the palm, cheek, and the back of the neck. Preference scores were most negative for the cheek, followed in order by the back of the neck, back of the hand, and palm (only among men). 4) Coldness scores were higher for body sites associated with a low two-point discrimination threshold, while preference scores were lower for body sites associated with larger pressure sensitivity thresholds. Relevance to industryThe above outcomes (1–4) are relevant for industries involved in the development of comfortable life spaces, including the electronics industry, for developing air-conditioning systems; the entertainment industry, for using air as a new medium of entertainment; and the lifestyle industry, for providing new standards of life to humans.

INTRAOPERATIVE DIAGNOSIS OF NEUROLOGICAL COMPLICATIONS IN SURGERY OF SEVERE SCOLIOSIS: REPORT OF CLINICAL CASES

Clinical observations of 13- and 15-year-old patients with severe (118° and 133°) idiopathic scoliosis, subjected to operative correction with the use of segmental instrumentation are presented. Intraoperative monitoring of the spinal cord function was performed by recording motor potentials of the brain and skin thermometry from the lower limbs (authors’ technique). During the operation, there was a gradual decrease in potentials in one case and sharp in another, with no changes in cutaneous temperature. Based on the data of skin thermometry, surgeons decided not to remove the implant and to bring the operation to completion in both cases. In the postoperative period, neurological complications were not revealed. The conclusion is made about the advisability of including the skin thermometry in a complex of intraoperative monitoring of spinal cord function in patients with spine deformities.

Roasted Barley Extract (Mugi-cha) Containing Cyclo(d-Phe-l-Pro) Prevents Lowering of the Cutaneous Blood Flow and Skin Temperature under Air Conditioning: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study.

Roasted barley extract (RBE), also known as mugi-cha, is a well-known healthy non-caffeinated beverage, and its health functionality has been widely reported. Our previous clinical study showed that RBE affects the cutaneous blood flow and skin temperature after cold-water immersion and that cyclo(d-Phe-l-Pro) is responsible for its effect. In this study, we investigated whether cyclo(d-Phe-l-Pro)-containing RBE prevents the decrease in the cutaneous blood flow and skin temperature. Subjects remained in the air-conditioned room while ingesting RBE or a placebo. We measured the cutaneous blood flow and skin temperature. We evaluated the effect of RBE administration by two-way repeated measures analysis of variance. A total of 15 subjects were enrolled. The change in cutaneous blood flow in the RBE and placebo groups was -0.79 ± 0.38 and -2.03 ± 0.35 mL min-1 100 g-1, respectively ( p value of 0.041). The change in the skin temperature in the RBE and placebo groups was -1.85 ± 0.35 and -3.02 ± 0.30 °C, respectively ( p value of <0.001). We also did subclass analysis with cold-feeling subjects. For the seven subjects who had cold sensation, the change in the cutaneous blood flow in the RBE and placebo groups was -0.48 ± 0.58 and -2.56 ± 0.48 mL min-1 100 g-1, respectively ( p value of 0.008). The change in the skin temperature in the RBE and placebo groups was -1.46 ± 0.74 and -2.89 ± 0.39 °C, respectively ( p value of 0.009). Thus, RBE containing cyclo(d-Phe-l-Pro) prevents the decrease in the cutaneous blood flow and skin temperature under air conditioning.