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Purpose Resveratrol has shown promising anti-inflammatory effects in in vitro and animal studies. We aimed to investigate this effect on arterial inflammation in vivo. Methods This was an additional analysis of a double-blind randomized crossover trial which included eight male subjects with decreased insulin sensitivity who underwent an (18) F-fluoroxyglucose ( (18) F-FDG) PET/CT after 34 days of placebo and resveratrol treatment (150 mg/day). (18) F-FDG uptake was analyzed in the carotid arteries and the aorta, adipose tissue regions, spleen, and bone marrow as measures for arterial and systemic inflammation. Maximum target-to-background ratios (TBR (max) ) were compared between resveratrol and placebo treatment with the non-parametric Wilcoxon signed-rank test. Median values are shown with their interquartile range. Results Arterial (18) F-FDG uptake was non-significantly higher after resveratrol treatment (TBR (max) all vessels 1.7 (1.6-1.7)) in comparison to placebo treatment (1.5 (1.4-1.6); p=0.050). Only in visceral adipose tissue, the increase in (18) F-FDG uptake after resveratrol reached statistical significance (p=0.024). Furthermore, CRP-levels were not significantly affected by resveratrol treatment (p=0.091). Conclusions Resveratrol failed to attenuate arterial or systemic inflammation as measured with (18) F-FDG PET in subjects at risk of developing type 2 diabetes. However, validation of these findings in larger human studies is needed.

In this field study, we tested the effects of dynamic light scenarios and personal illuminance on visual experience, sleepiness, cognitive performance and sleep in an operational office. Two dynamic light scenarios, different in timing but with equal luminous exposure, were tested against a reference scenario in a counterbalanced crossover design. Frequent assessments of visual experience, alertness, performance and sleep showed that in both dynamic light scenarios visual comfort was slightly lower compared to the constant scenario. Additionally, sleepiness was lowest in the scenario with the brighter light timed around noon, whereas task performance and actual sleep were not significantly affected. The measured personal illuminance did not predict sleepiness and performance, yet variation and timing of these illuminances did positively relate to sleep onset and duration. When studying or implementing light scenarios aiming to deliver integrative lighting, the spatial and behavioral context should be considered as well.

The classical textbook interpretation of thermal comfort is that it occurs when the thermoregulatory effort is minimized. However, stimulating human thermoregulatory systems may benefit health and increase body thermal resilience. To address this gap, we tested a novel personal comfort system (PCS) that targets only the extremities and the head, leaving the rest of the body exposed to a moderately drifting temperature (17–25°C). A randomized, cross-over study was conducted under controlled laboratory conditions, mimicking an office setting. Eighteen participants completed two scenarios, one with a PCS and another one without a PCS in 17–25°C ambient conditions. The results indicate that the PCS improved thermal comfort in 17–23°C and retained active thermoregulatory control. The torso skin temperature, underarm-finger temperature gradients, energy expenditure, substrate oxidations and physical activity were not affected by the PCS in most cases. Only slight changes in cardiovascular responses were observed between the two scenarios. Moreover, the PCS boosted pleasure and arousal. At 25°C, the PCS did not improve thermal comfort, but significantly improved air quality perceptions and mitigated eye strain. These findings suggest that human physiological thermoregulation can be stimulated without compromising thermal comfort by using a PCS that only targets the extremities in cold conditions.

Purpose: Upper-body exercise performed in a cold environment may increase cardiovascular strain, which could be detrimental to patients with coronary artery disease (CAD). This study compared cardiovascular responses of CAD patients during graded upper-body dynamic and static exercise in cold and neutral environments. Methods: 20 patients with stable CAD performed 30 min of progressive dynamic (light, moderate, and heavy rating of perceived exertion) and static (10, 15, 20, 25 and 30% of maximal voluntary contraction) upper body exercise in cold (− 15 °C) and neutral (+ 22 °C) environments. Heart rate (HR), blood pressure (BP) and electrocardiographic (ECG) responses were recorded and rate pressure product (RPP) calculated. Results: Dynamic-graded upper-body exercise in the cold increased HR by 2.3–4.8% (p = 0.002–0.040), MAP by 3.9–5.9% (p = 0.038–0.454) and RPP by 18.1–24.4% (p = 0.002–0.020) when compared to the neutral environment. Static graded upper-body exercise in the cold resulted in higher MAP (6.3–9.1%; p = 0.000–0.014), lower HR (4.1–7.2%; p = 0.009–0.033), but unaltered RPP compared to a neutral environment. Heavy dynamic exercise resulted in ST depression that was not related to temperature. Otherwise, ECG was largely unaltered during exercise in either thermal condition. Conclusions: Dynamic- and static-graded upper-body exercise in the cold involves higher cardiovascular strain compared with a neutral environment among patients with stable CAD. However, no marked changes in electric cardiac function were observed. The results support the use of upper-body exercise in the cold in patients with stable CAD. Trial registration: Clinical trial registration NCT02855905 August 2016.

Lifestyle interventions, obviating the increasing prevalence of the metabolic syndrome, generally focus on nutrition and physical activity. Environmental factors are hardly covered. Because we spend on average more that 90% of our time indoors, it is, however, relevant to address these factors. In the built environment, the attention has been limited to the (assessment and optimization of) building performance and occupant thermal comfort for a long time. Only recently well-being and health of building occupants are also considered to some extent, but actual metabolic health aspects are not generally covered. In this review, we draw attention to the potential of the commonly neglected lifestyle factor indoor environment'. More specifically, we review current knowledge and the developments of new insights into the effects of ambient temperature, light and the interaction of the two on metabolic health. The literature shows that the effects of indoor environmental factors are important additional factors for a healthy lifestyle and have an impact on metabolic health.

The purpose of this study was to assess the impact of postexercise hot-water immersion on postprandial myofibrillar protein synthesis rates during recovery from a single bout of resistance-type exercise in healthy. young men. Twelve healthy, adult men (age: 23 +/- 1 y) performed a single bout of resistance-type exercise followed by 20 min of water immersion of both legs. One leg was immersed in hot water [46 degrees C: hot-water immersion (HWI)], while the other leg was immersed in thermoneutral water (30 degrees C: CON). After water immersion, a beverage was ingested containing 20 g intrinsically L-[1-C-13]-phenylalanine and L-[1-C-13]-leucine labeled milk protein with 45 g of carbohydrates. In addition, primed continuous L-[ring-H-2(5)]-phenylalanine and L-[1-C-13]-leucine infusions were applied, with frequent collection of blood and muscle samples to assess myofibrillar protein synthesis rates in vivo over a 5-h recovery period. Muscle temperature immediately after water immersion was higher in the HWI compared with the CON leg (37.5 +/- 0.1 vs. 35.2 +/- 0.2 degrees C; P <0.001). Incorporation of dietary protein-derived [1-C-13]-phenylalanine into myofibrillar protein did not differ between the HWI and CON leg during the 5-h recovery period (0.025 +/- 0.003 vs. 0.024 +/- 0.002 MPE; P = 0.953). Postexercise myofibrillar protein synthesis rates did not differ between the HWI and CON leg based upon L-[1-C-13]-eucine (0.050 +/- 0.005 vs. 0.049 +/- 0.002%/h; P = 0.815) and L-[ring-H-2(5)]-phenylalanine (0.048 +/- 0.002 vs. 0.047 +/- 0.003%/h; P = 0.877), respectively. Hot-water immersion during recovery from resistancetype exercise does not increase the postprandial rise in myolibrillar protein synthesis rates. In addition, postexercise hot-water immersion does not increase the capacity of the muscle to incorporate dietary protein-derived amino acids in muscle tissue protein during subsequent recovery.NEW & NOTEWORTHY This is the first study to assess

Studies indicate that the energy performance gap between real and calculated energy use can be explained for 80% by occupant behaviour. This human factor may be composed of routine and thermoregulatory behaviour. When occupants do not feel comfortable due to high or low operative temperatures and resulting high or low skin temperatures, they are likely to exhibit thermoregulatory behaviour. The aim of this study is to monitor and understand this thermoregulatory behaviour of the occupant. This is a detailed study of two females living in a rowhouse in the city of Heerlen (Netherlands). During a monitoring period of three weeks over a time span of three months the following parameters were monitored: activity level, clothing, micro climate, skin temperatures and thermal comfort and sensation. Their micro climate was measured at five positions on the body to assess exposed near body conditions and skin temperature. Every two hours they filled in a questionnaire regarding their thermal comfort and sensation level (7-point scale), clothing, activities and thermoregulatory behaviour. The most comfortable (optimal) temperature was calculated for each person by adopting a biophysical model, a thermoneutral zone model. This study shows unique indivual comfort patterns in relation to ambient conditions. An example is given how this information can be used to calculate the buildings energy comsumption.

Regular year-round exercise is recommended for patients with coronary artery disease (CAD). However, the combined effects of cold and moderate sustained exercise, both known to increase cardiac workload, on cardiovascular responses are not known. We tested the hypothesis that cardiac workload is increased, and evidence of ischemia would be observed during exercise in the cold in patients with CAD. Sixteen men (59.3 ± 7.0 yr, means ± SD) with stable CAD each underwent 4, 30 min exposures in a randomized order: seated rest and moderate-intensity exercise [walking, 60%–70% of max heart rate (HR)] performed at +22°C and −15°C. Systolic brachial blood pressure (SBP), HR, electrocardiogram (ECG), and skin temperatures were recorded throughout the intervention. Rate pressure product (RPP) and ECG parameters were obtained. The combined effects of cold and submaximal exercise were additive for SBP and RPP and synergistic for HR when compared with rest in a neutral environment. RPP (mmHg·beats/min) was 17% higher during exercise in the cold (18,080 ± 3540) compared with neutral (15,490 ± 2,940) conditions (P = 0.001). Only a few ST depressions were detected during exercise but without an effect of ambient temperature. The corrected QT interval increased while exercising in the cold compared with neutral temperature (P = 0.023). Recovery of postexercise blood pressure was similar regardless of temperature. Whole body exposure to cold during submaximal exercise results in higher cardiac workload compared with a neutral environment. Despite the higher RPP, no signs of myocardial ischemia or abnormal ECG responses were observed. The results of this study are useful for planning year-round exercise-based rehabilitation programs for stable CAD patients.

Public and commercial buildings tend to overheat. Recent studies indicate individual comfort systems based on local climatization can improve occupant satisfaction and simultaneously decrease the energy load of buildings. This study evaluated the effect of local cooling in both women and men on indicators of occupant satisfaction: thermal sensation, thermal comfort and skin temperatures. All measurements were conducted in a climate chamber (Priva, the Netherlands) with an ambient temperature of 32.3 +/- 0.3 degrees C (mean +/- SD). In total, 16 healthy young men and women were exposed to different local cooling conditions for 45 min: face cooling, back cooling, underarm cooling, foot sole cooling and 30 min of combined face-underarm cooling. The cooling conditions were separated by 30 min of 'no cooling'. Thermal sensation and thermal comfort were evaluated with VAS-scales. Skin temperatures (26 sites) were measured using wireless temperature sensors. 'Face cooling' and combined 'face-underarm cooling' significantly improved thermal sensation and comfort compared with 'no cooling' for both women and men. Women had significantly higher skin temperatures compared with men. Local cooling of the face alone and face and underarms combined are effective ways to improve thermal sensation and thermal comfort in a warm thermal environment.

The interest in brown adipose tissue (BAT) as a target to combat metabolic disease has recently been renewed with the discovery of functional BAT in humans. In rodents, BAT can be activated by bile acids, which activate type 2 iodothyronine deiodinase (D2) in BAT via the G-coupled protein receptor TGR5, resulting in increased oxygen consumption and energy expenditure. Here we examined the effects of oral supplementation of the bile acid chenodeoxycholic acid (CDCA) on human BAT activity. Treatment of 12 healthy female subjects with CDCA for 2 days resulted in increased BAT activity. Whole-body energy expenditure was also increased upon CDCA treatment. In vitro treatment of primary human brown adipocytes derived with CDCA or specific TGR5 agonists increased mitochondrial uncoupling and D2 expression, an effect that was absent in human primary white adipocytes. These findings identify bile acids as a target to activate BAT in humans.

Many researchers have already attempted to model vasoconstriction responses, commonly using the mathematical representation proposed by Stolwijk (1971 NASA Contractor Report CR-1855 (Washington, DC: NASA)). Model makers based the parameter values in this formulation either on estimations or by attributing the difference between their passive models and measurement data fully to thermoregulation. These methods are very sensitive to errors. This study aims to present a reliable method for determining physiological values in the vasoconstriction formulation. An experimental protocol was developed that enabled us to derive the local proportional amplification coefficients of the toe, leg and arm and the transient vasoconstrictor tone. Ten subjects participated in a cooling experiment. During the experiment, core temperature, skin temperature, skin perfusion, forearm blood flow and heart rate variability were measured. The contributions to the normalized amplification coefficient for vasoconstriction of the toe, leg and arm were 84%, 11% and 5%, respectively. Comparison with relative values in the literature showed that the estimated values of Stolwijk and the values mentioned by Tanabe et al (2002 Energy Build. 34 637-46) were comparable with our measured values, but the values of Gordon (1974 The response of a human temperature regulatory system model in the cold PhD Thesis University of California, Santa Barbara) and Fiala et al (2001 Int. J. Biometeorol. 45 143159) differed significantly. With the help of regression analysis a relation was formulated between the error signal of the standardized core temperature and the vasoconstrictor tone. This relation was formulated in a general applicable way, which means that it can be used for situations where vasoconstriction thresholds are shifted, like under anesthesia or during motion sickness.

Summary Large inter-individual differences in cold-induced (non-shivering) and diet-induced adaptive thermogenesis exist in animals and humans. These differences in energy expenditure can have a large impact on long-term energy balance and thus body weight (when other factors remain stable). Therefore, the level of adaptive thermogenesis might relate to the susceptibility to obesity; efforts to increase adaptive thermogenesis might be used to treat obesity. In small mammals, the main process involved is mitochondrial uncoupling in brown adipose tissue (BAT), which is regulated by the sympathetic nervous system. For a long time, it was assumed that mitochondrial uncoupling is not a major physiological contributor to adaptive thermogenesis in adult humans. However, several studies conducted in recent years suggest that mitochondrial uncoupling in BAT and skeletal muscle tissue in adult humans can be physiologically significant. Other mechanisms besides mitochondrial uncoupling that might be involved are futile calcium cycling, protein turnover and substrate cycling. In conjunction with recent advances on signal transduction studies, this knowledge makes manipulation of adaptive thermogenesis a more realistic option and thus a pharmacologically interesting target to treat obesity.

As a result of the inefficiency of metabolic transfer, >75% of the energy that is generated by skeletal muscle substrate oxidation is liberated as heat. During exercise, several powerful physiological mechanisms of heat loss are activated to prevent an excessive rise in body core temperature. However, a hot and humid environment can significantly add to the challenge that physical exercise imposes on the human thermoregulatory system, as heat exchange between body and environment is substantially impaired under these conditions. This can lead to serious performance decrements and an increased risk of developing heat illness. Fortunately, there are a number of strategies that athletes can use to prevent and/or reduce the dangers that are associated with exercise in the heat. In this regard, heat acclimatisation and nutritional intervention seem to be most effective. During heat acclimatisation, the temperature thresholds for both cutaneous vasodilation and the onset of sweating are lowered, which, in combination with plasma volume expansion, improve cardiovascular stability. Effective nutritional interventions include the optimisation of hydration status by the use of fluid replacement beverages. The latter should contain moderate amounts of glucose and sodium, which improve both water absorption and retention.

For over a century, centrifugal pumps (CP) have been used in various applications, from large industrial pumps to flow pumps for aquariums. However, the use of CP as blood pumps has a rather short history. Consequently, the hydraulic performance data for a blood CP are limited. The aim of our investigation was to study the hydraulic performance and the heat generation of three commercially available CP: Bio-Medicus Bio-Pump BP80 (Medtronic), Rotaflow (Jostra Medizintechnik), and DeltaStream DP2 (MEDOS Medizintechnik AQ). The study was performed using a circuit primed with a water-glycerin mixture with a dynamic viscosity of 0.00272 pa/s. Pressure-flow curves were obtained by a stepwise stagnation of the pump outlet or inlet. The temperature changes were observed using ThermaCAM SC2000 (Flir Systems). The pumps' performance in close to clinical conditions ('operating region') was analysed in this report. The 'operating region' in the case of the BP80 is positioned around the pressure-flow curve at a pump speed of 3000 rpm. In the case of the Rotaflow, the 'operating region' was between the pump pressure-flow curves at a speed of 3000 and 4000 rpm, and the DP2 was found between 7000 and 8000 rpm. The standard deviation of mean pressure through the pump was used to characterise the stability of the pump. In experiments with outlet stagnation, the BP80 demonstrated high negative association between flow and pressure variability (r = -0.68, p < 0.001). In experiments with the DP2, this association was positive (r = 0.68, p < 0.001). All pumps demonstrated significantly higher variability of pressure in experiments with inlet stagnation in comparison to the experiments with outlet stagnation. The rise of relative temperature in the inlet of a pump was closely related to the flow rate. The heating of fluid was more pronounced in the 'zero-flow' mode, especially in experiments with inlet stagnation. In summary, (1) the 'zero-flow' regime, which is described in the man

BACKGROUND: Underweight and micronutrient deficiencies are sequelae of the prevailing harsh living and economic conditions of women in sub-Saharan Africa. There are few data describing maternal nutritional status in these resource-poor settings. Provision of more effective modes of intervention requires that public health and nutrition policy at both the national and the multisectoral levels be based on community-specific nutritional and behavioral practices. OBJECTIVE: This longitudinal study investigated maternal micronutrient status in two remote, semiarid, rural communities that are ethnically similar but have distinctly different pastoral and farming lifestyles. We looked at differences in iron stores, vitamin A levels, and body composition of women in the third trimester of pregnancy and again at 4 months postpartum. METHODS: Complete data were collected from 113 pastoral and 110 farming Pokot women. Anthropometric measurements were taken, and serum ferritin and retinol levels were measured. Infants were weighed within 7 days of birth. RESULTS: Women from the farming community had significantly (p < .05) lower hemoglobin concentrations than women from the pastoral community during the third trimester of pregnancy. Pastoral women had significantly higher serum ferritin concentrations than farming women during the third trimester of pregnancy (p <.05) and at 4 months postpartum. There were no significant differences between pastoral and farming women in the percentage of women with serum retinol levels < 0.70 micromol/L during the third trimester of pregnancy (27.9% [34/113] and 24.2% [31/110], respectively) and at 4 months postpartum (29.2% [33/113] and 30.9% [34/110]) In the farming community, mean infant birthweight was significantly lower (p <. 01) than in the pastoral community and a significantly higher (p < .05) proportion of newborns weighed less than 2.5 kg. At 4 months postpartum, the percentage of body fat was significantly lower in pas